Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf
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Only approved publications
43570 Publications
Breaking the Vicious Cycle of Warm Dense Matter Diagnostics
Abstract
Matter at extreme densities and temperatures displays a complex quantum behavior that is characterized by Coulomb interactions, thermal excitations, and partial ionization. Such warm dense matter (WDM) is ubiquitous throughout the universe and occurs in a host of astrophysical objects such as giant planet interiors and white dwarf atmospheres. A particularly intriguing application is given by inertial confinement fusion, where both the fuel capsule and the ablator have to traverse the WDM regime in a controlled way to reach ignition.
In practice, rigorously understanding WDM is highly challenging both from experimental measurements and numerical simulations [1]. On the one hand, interpreting and diagnosing experiments with WDM requires a suitable theoretical description. One the other hand, there is no single method that is capable of accurately describing the full range of relevant densities and temperatures, and the interpretation of experiments is, therefore, usually based on a number of de-facto uncontrolled approximations. The result is the vicious cycle of WDM diagnostics: making sense of experimental observations requires theoretical modeling, whereas theoretical models must be benchmarked against experiments to verify their inherent assumptions.
In this work, we outline a strategy to break this vicious cycle by combining the X-ray Thomson scattering (XRTS) technique [2] with new ab initio path integral Monte Carlo (PIMC) capabilities [3,4,5]. As a first step, we have proposed to interpret XRTS experiments in the imaginary-time (Laplace) domain, which allows for the model-free diagnostics of the temperature [6] and normalization [7]. Moreover, by switching to the imaginary-time, we can directly compare our quasi-exact PIMC calculations with the experimental measurement [5]. This opens up novel ways to diagnose the experimental conditions, as we have recently demonstrated for the case of strongly compressed beryllium at the National Ignition Facility.
Our results open up new possibilities for improved XRTS set-ups that are specifically designed to be sensitive to particular parameters of interest [8]. Moreover, the presented PIMC capabilities are important in their own right and will allow for a gamut of applications, including equation-of-state calculations and the estimation of structural properties and linear response functions.
[1] T. Dornheim et al., Phys. Plasmas 30, 032705 (2023) [2] S. Glenzer and R. Redmer, Rev. Mod. Phys. 81, 1625 (2009) [3] T. Dornheim et al., J. Phys. Chem. Lett. 15, 1305-1313 (2024) [4] T. Dornheim et al., arXiv:2403.01979 [5] T. Dornheim et al., arXiv:2402.19113 [6] T. Dornheim et al., Nature Commun. 13, 7911 (2022) [7] T. Dornheim et al., arXiv:2305.15305 [8] Th. Gawne et al., arXiv:2403.02776
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Invited lecture (Conferences)
HEDLA-2024: The 14th International Conference on High Energy Density Laboratory Astrophysics, 20.-24.05.2024, Tallahassee, USA
Permalink: https://www.hzdr.de/publications/Publ-39155
Quantum delocalization, structural order, and density response of the strongly coupled electron liquid
Dornheim, T.; Tolias, P.; Vorberger, J.; Moldabekov, Z.
Abstract
We investigate the impact of electronic correlations and quantum delocalization onto the static structure factor and static density response function of the strongly coupled electron liquid. In contrast to a classical system, the density response of the electron liquid vanishes on small length scales due to quantum delocalization effects, which we rigorously quantify in terms of imaginary-time correlation functions and dynamic Matsubara response functions. This allows us to analyze the interplay of structural order and dynamic quantum effects as it manifests in the dynamic Matsubara local field correction. Finally, we identify an effective electronic attraction in the spin-offdiagonal static density response when the wavelength of the perturbation is commensurate with the average interparticle distance.
Related publications
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Data publication: Quantum delocalization, structural order, and density …
ROBIS: 39310 HZDR-primary research data are used by this (Id 39154) publication
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EPL - Europhysics Letters 147(2024)3, 36001
DOI: 10.1209/0295-5075/ad5d88
Cited 1 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39154
Toward first principles simulations of dense hydrogen
Bonitz, M.; Vorberger, J.; Bethkenhagen, M.; Böhme, M.; Ceperley, D.; Filinov, A.; Gawne, T. D.; Graziani, F.; Gregori, G.; Hamann, P.; Hansen, S.; Holzmann, M.; Hu, S.; Kählert, H.; Karasiev, V.; Kleinschmidt, U.; Kordts, L.; Makait, C.; Militzer, B.; Moldabekov, Z.; Pierleoni, C.; Preising, M.; Ramakrishna, K.; Redmer, R.; Schwalbe, S.; Svensson, P.; Dornheim, T.
Abstract
Accurate knowledge of the properties of hydrogen at high compression is crucial for astrophysics (e.g. planetary and stellar interiors, brown dwarfs, atmosphere of compact stars) and laboratory experiments, including inertial confinement fusion. There exists experimental data for the equation of state, conductivity, and Thomson scattering spectra. However, the analysis of the measurements at extreme pressures and temperatures typically involves additional model assumptions, which makes it difficult to assess the accuracy of the experimental data. rigorously. On the other hand, theory and modeling have produced extensive collections of data. They originate from a very large variety of models and simulations including path integral Monte Carlo (PIMC) simulations, density functional theory (DFT), chemical models, machine-learned models, and combinations thereof. At the same time, each of these methods has fundamental limitations (fermion sign problem in PIMC, approximate exchange-correlation functionals of DFT, inconsistent interaction energy contributions in chemical models, etc.), so for some parameter ranges accurate predictions are difficult. Recently, a number of breakthroughs in first principle PIMC and DFT simulations were achieved which are discussed in this review. Here we use these results to benchmark different simulation methods. We present an update of the hydrogen phase diagram at high pressures, the expected phase transitions, and thermodynamic properties including the equation of state and momentum distribution. Furthermore, we discuss available dynamic results for warm dense hydrogen, including the conductivity, dynamic structure factor, plasmon dispersion, imaginary-time structure, and density response functions. We conclude by outlining strategies to combine different simulations to achieve accurate theoretical predictions.
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Physics of Plasmas 31(2024), 110501
DOI: 10.1063/5.0219405
Cited 2 times in Scopus
Downloads
Permalink: https://www.hzdr.de/publications/Publ-39153
Tuning the Electronic Characteristics of Monolayer MoS2-Based Transistors by Ion Irradiation: The Role of the Substrate
Fekri, Z.; Chava, P.; Hlawacek, G.; Ghorbani Asl, M.; Kretschmer, S.; Awan, W.; Koladi Mootheri, V.; Sycheva, N.; George, A.; Turchanin, A.; Watanabe, K.; Taniguchi, T.; Helm, M.; Krasheninnikov, A.; Erbe, A.
Abstract
This study explores defect engineering in 2D materials using ion beam irradiation to modify the electrical and optical properties with potential in advancing quantum electronics and photonics. Helium and neon ions ranging from 5 to 7.5 keV are employed to manipulate charge transport in monolayer molybdenum disulfide (MoS2). In situ electrical characterization occurs without vacuum breakage post-irradiation. Raman and photoluminescence spectroscopy quantify ion irradiation’s impact on MoS2. Small doses of helium ion irradiation enhance monolayer MoS2 conductivity in field-effect transistor geometry by inducing doping and substrate charging. Findings reveal a strong correlation between the electrical properties of MoS2 and the primary ion used, as well as the substrate on which the irradiation occurred. Using hexagonal boron nitride (h-BN) as a buffer layer between MoS2 flake and SiO2 substrate yields distinct alterations in electrical behavior subsequent to ion irradiation compared to the MoS2 layer directly interfacing with SiO2. Molecular dynamics simulations and density functional theory provide insight into experimental results, emphasizing substrate influence on measured electrical properties post-ion irradiation.
Keywords: defects; FET; first-principles calculations; ion irradiation; monolayer MoS2
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 39152) publication
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Data publication: Tuning the Electronic Characteristics of Monolayer …
ROBIS: 39191 HZDR-primary research data are used by this (Id 39152) publication
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Advanced Electronic Materials 10(2024)9, 2400037
DOI: 10.1002/aelm.202400037
Permalink: https://www.hzdr.de/publications/Publ-39152
The Backscatter Gating method for time, energy, and position resolution characterization of long form factor organic scintillators
Ratliff, H. N.; Kögler, T.; Pausch, G.; Setterdahl, L. M.; Skjerdal, K.; Turko, J. A. B.; Meric, I.
Abstract
This work details a Compton-scattering-based methodology, referred to as Backscatter Gating (BSG), for characterizing the time, energy, and position resolutions of long form factor organic scintillators using a single, fairly minimal measurement setup. Such a method can ease the experimental burden in scenarios where many such scintillator elements may need to be individually characterized before assembly into a larger detector system. A thorough theoretical exploration of the systematic parameters is provided, and the BSG method is then demonstrated by a series of experimental measurements. This “complete” characterization via the BSG method is novel, having previously been used primarily for energy resolution characterization. The method also allows for determination of the assembled scintillator’s technical attenuation length and provides a means of verifying the presence or absence of flaws within the scintillator or its optical coupling.
Keywords: Trigger concepts and systems (hardware and software); Detector alignment calibration methods
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Journal of Instrumentation 19(2024)07, P07002
DOI: 10.1088/1748-0221/19/07/P07002
ISSN: 1748-0221
Permalink: https://www.hzdr.de/publications/Publ-39150
Zirconium Oxynitride Thin Films for Photoelectrochemical Water Splitting
Streibel, V.; Schönecker, J. L.; Wagner, L. I.; Sirotti, E.; Munnik, F.; Kuhl, M.; Jiang, C.-M.; Eichhorn, J.; Santra, S.; Sharp, I. D.
Abstract
Transition metal oxynitrides are a promising class of functional materials for photoelectrochemical (PEC) applications. Although these compounds are most commonly synthesized via ammonolysis of oxide precursors, such synthetic routes often lead to poorly controlled oxygen-to-nitrogen anion ratios, and the harsh nitridation conditions are incompatible with many substrates, including transparent conductive oxides. Here, we report direct reactive sputter deposition of a family of zirconium oxynitride thin films and the comprehensive characterization of their tunable structural, optical, and functional PEC properties. Systematic increases of the oxygen content in the reactive sputter gas mixture enable access to different crystalline structures within the zirconium oxynitride family. Increasing oxygen contents lead to a transition from metallic to semiconducting to insulating phases. In particular, crystalline Zr2ON2-like films have band gaps in the UV−visible range and are n-type semiconductors. These properties, together with a valence band maximum position located favorably relative to the water oxidation potential, make them viable photoanode candidates. Using chopped linear sweep voltammetry, we indeed confirm that our Zr2ON2 films are PEC-active for the oxygen evolution reaction in alkaline electrolytes. We further show that high-vacuum annealing boosts their PEC performance characteristics. Although the observed photocurrents are low compared to state-of-the-art photoanodes, these dense and planar thin films can offer a valuable platform for studying oxynitride photoelectrodes, as well as for future nanostructuring, band gap engineering, and defect engineering efforts.
Keywords: zirconium oxynitride; reactive sputtering; thin film photoanodes; photoelectrochemical water splitting; oxygen evolution reaction; water oxidation
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 39149) publication
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ACS Applied Energy Materials 7(2024), 4004-4015
DOI: 10.1021/acsaem.4c00303
Cited 3 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39149
Data publication: Multiferroic Microstructure Created from Invariant Line Constraint
Kar, S.; Ikeda, Y.; Nielsch, K.; Reith, H.; Maaß, R.; Fähler, S.
Abstract
This dataset contains all raw data used for the publication of the paper "Multiferroic Microstructure Created from Invariant Line Constraint" including SEM, TEM, MFM, VSM, RXD data.
Keywords: Multiferroics; Martensite; Magnetic shape memory alloys; Ni-Mn-Ga-based alloys; Epitaxial films; Finite-size effects
Related publications
- DOI: 10.1002/adfm.202416638 references this (Id 39148) publication
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Multiferroic Microstructure Created from Invariant Line Constraint
ROBIS: 39147 has used this (Id 39148) publication of HZDR-primary research data
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Reseach data in the HZDR data repository RODARE
Publication date: 2024-05-28 Open access
DOI: 10.14278/rodare.2888
Versions: 10.14278/rodare.2889
License: CC-BY-4.0
Downloads
Permalink: https://www.hzdr.de/publications/Publ-39148
Multiferroic Microstructure Created from Invariant Line Constraint
Kar, S.; Ikeda, Y.; Nielsch, K.; Reith, H.; Maaß, R.; Fähler, S.
Abstract
Ferroic materials enable a multitude of emerging applications, and optimum functional properties are achieved when ferromagnetic and ferroelectric properties are coupled to a first-order ferroelastic transition. In bulk materials, this first-order transition involves an invariant habit plane, connecting coexisting phases: austenite and martensite. Theory predicts that this plane should converge to a line in thin films, but experimental evidence is missing. Here, we analyze the martensitic and magnetic microstructure of a freestanding epitaxial magnetic shape memory film. We show that the martensite microstructure is determined by an invariant line constraint using lattice parameters of both phases as the only input. This line constraint explains most of the observable features, which differ fundamentally from bulk and constrained films. Furthermore, this finite-size effect creates a remarkable checkerboard magnetic domain pattern through multiferroic coupling. Our findings highlight the decisive role of finite-size effects in multiferroics.
Keywords: Multiferroics; Martensite; Magnetic shape memory alloys; Ni-Mn-Ga-based alloys; Epitaxial films; Finite-size effects
Related publications
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Data publication: Multiferroic Microstructure Created from Invariant Line …
ROBIS: 39148 HZDR-primary research data are used by this (Id 39147) publication
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Advanced Functional Materials (2025), 2416638
Online First (2024) DOI: 10.1002/adfm.202416638
Permalink: https://www.hzdr.de/publications/Publ-39147
Dynamics of Lagrangian Sensor Particles: The Effect of Non-Homogeneous Mass Distribution
Rautenbach, R.; Hofmann, S.; Buntkiel, L.; Schäfer, J.; Reinecke, S.; Hoffmann, M.; Hampel, U.; Schlüter, M.
Abstract
The growing demand for bio-pharmaceuticals necessitates improved methods for the
characterization of stirred tank reactors (STR) and their mixing heterogeneities. Traditional Eulerian
measurement approaches fall short, culminating in the use of Lagrangian Sensor Particles (LSP) to
map large-scale STRs and track the lifelines of microorganisms such as Chinese Hamster Ovary cells.
This study investigates the hydrodynamic characteristics of LSPs, specifically examining the effects
that size and position of the Center of Mass (CoM) has on their flow-following capabilities. Two
Lagrangian Particle (LP) designs are evaluated, one with CoM and Geometric Center aligned, and
another with a shifted CoM. The experimental study is conducted in a rectangular vessel filled with
deionized water featuring a stationary circular flow. Off-center LPs exhibit higher velocities, an
increased number of floor contacts, and moreover, a less homogeneous particle probability of presence
within the vessel compared to LPs with CoM and Geometric center aligned. Lattice-Boltzmann Large
Eddy Simulations provide complementary undisturbed fluid velocity data for the calculation of the
Stokes number St. Building upon these findings, differences in the Stokes number St between the
two LP variants of ΔSt = 0.01 (25 mm LP) and ΔSt = 0.13 (40 mm LP) are calculated, highlighting
the difference in flow behavior. Furthermore, this study offers a more representative calculation
of particle response time approach, as the traditional Stokes number definition does not account
for non-homogeneous particles, resulting in an alternative Stokes number (ΔStalt = 0.84 (25 mm
LP) and ΔStalt = 2.72 (40 mm LP)). This study contributes to the improved characterization of STRs
through the use of Lagrangian Sensor Particles. Results highlight the implications the internal mass
distribution has on LSP design, offering crucial considerations for researchers in the field.
Keywords: Stirred Tank Reactors; Lagrangian Sensor Particles; Mixing Heterogeneities; Stokes Number; Non-Homogeneous Particles; Flow-Following
Related publications
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Processes data and code for Dynamics of Lagrangian Sensor Particles
ROBIS: 39366 HZDR-primary research data are used by this (Id 39146) publication
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Processes 12(2024)8
DOI: 10.3390/pr12081617
Cited 1 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39146
Investigating the influence of (de)wetting(ability) heterogeneities using atomic force microscopy on the separation of ultrafine particles via froth flotation
Sygusch, J.; Graebe, K.; Rudolph, M.
Abstract
Froth flotation is an efficient separation process for particles with sizes between 10 μm and 200 μm, which is based on differences in the particle wettabilities, or more precisely dewettingability. Therefore, a fundamental understanding of the interfacial properties is required. Within the project MultiDimFlot, which is part of the priority programme SPP2045, funded by the German research foundation (DFG), the selective separation of ultrafine particles (< 10 μm) according to multiple particle properties (e.g. wettability, shape, size) by flotation is investigated. For this purpose, two ultrafine glass particle fractions with different shapes are used, i.e. glass spheres and fragments, and their wettability is modified via an esterification reaction using alcohols, where the wettability of the esterified particles is controlled by the length of the alkyl chain.
In order to investigate the influence of wetting heterogeneities on the separation via flotation, glass slides with the same chemical composition as the glass particles and that were esterified in the same way, were analysed via atomic force microscopy (AFM). By applying colloidal probe AFM in dry and liquid mode, information on the hydrophobic interactions on the surface of the glass slides with different levels of wettability are obtained. Furthermore, the esterified glass slides are analysed by measuring static and dynamic contact angles against water using the sessile drop method. This information is set into context with the surface energy results of the glass particles, obtained via inverse gas chromatography as well as results obtained by liquid-liquid extraction of particles, which is used to study the behaviour of the particles at the interface.
The correlation of the various methods shed light on the (de)wetting(ability) heterogeneities, how these are changed through esterification and how these results can be transferred to flotation.
Keywords: wettability; wetting heterogeneities; atomic force microscopy; flotation; esterification; ultrafine particles; surface energy; contact angles
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Poster
Jahrestreffen der DECHEMA/VDI-Fachgruppen Grenzflächenbestimmte Systeme und Prozesse, Kristallisation, Mechanische Flüssigkeitsabtrennung und Partikelmesstechnik, 27.-28.02.2024, Frankfurt, Deutschland
Permalink: https://www.hzdr.de/publications/Publ-39144
Novel 18F-labeled benzimidazolone-based radioligands as highly selective sigma-2 receptor probes for tumor imaging
Wang, J.; Wang, T.; Mou, T.; Yang, T.; Gao, X.; An, X.; Hu, B.; Zhang, J.; Zhang, X.; Deuther-Conrad, W.; Huang, Y.; Jia, H.
Abstract
Novel sigma-2 (σ2) receptor ligands with benzimidazolone and 5,6-dimethoxyisoindoline as pharmacophores were designed and synthesized. Compound 4 exhibited low nanomolar affinity for the σ2 receptors (Ki(σ2) = 2.30 nM) and high subtype selectivity (Ki(σ1)/Ki(σ2) = 1571). Radioligand [18F]4 was prepared in radiochemical yields of 18 ± 7%, with > 99% radiochemical purity and molar activity of 210 ± 134 GBq/μmol. Biodistribution and blocking studies in mice and small animal PET/CT imaging in rats indicated highly specific binding of [18F]4 in organs known to express the σ2 receptors. Small animal PET/CT imaging with [18F]4 in subcutaneous A549 lung cancer and U87MG glioma xenograft and intracranial orthotopic U87MG glioma models showed clear visualization of the tumor. Co-administration of CM398 with [18F]4 significantly reduced activity uptake in the tumors, indicating that [18F]4 specifically binds to the σ2 receptors expressed in A549 and U87MG xenografts.
Keywords: σ2 receptor; 5,6-dimethoxyisoindole; benzimidazolone; non-small cell lung tumor; glioma
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Journal of Medicinal Chemistry 67(2024)19, 17392-17406
DOI: 10.1021/acs.jmedchem.4c01315
Permalink: https://www.hzdr.de/publications/Publ-39143
Study of the Water and Steam Resistance of Thick Film Materials for Sensor Application up to 300 °C
Mueller, M.; Saakyan, S.; Luniak, M.; Pietruske, H.; Schleicher, E.; Panchenko, J.
Abstract
The present study focuses on the durability of regular thick film materials for sensor applications in harsh water/steam environment by autoclave storage. Two experiments have been arried out. The first experimental run focuses on insulating materials typically used for thick film manufacturing. Two glass based overglazes, a glass based dielectric paste as well as the polymers PEEK and polyimide were tested in five consecutive autoclave experiments ranging from 110 °C/0.16 MPa to 287 °C/7.03 MPa, with a storage time of approx. 48 h per run. Weight measurements and optical investigations after each experiment showed, that all glass-based insulators failed already during the 172 °C/0.83 MPa storage. The polyimide failed at 222 °C/2.37 MPa and the PEEK layer survived but started to lose adhesion to the substrate during the 172 °C storage. It has been shown that the standard 96 % Al2O3 thick film substrate is not suitable for this environment and shows strong degradation, while high purity 99.6 % Al2O3 and ZrO2 (Y2O3 stabilized) resist even 290 °C/7.35 MPa. A second set of experiments focuses on the application of mostly metallic passivation layers for these vulnerable insulators. The results show that double layers of the investigated AgPt and Au thick film pastes are most reliable even at 290 °C/7.35 MPa, while single layers of AgPt and Pt paste offer no hermetic sealing and cause failure. Thin Ti films (300 nm and 500 nm) show good passivation capabilities at 152 °C/0.5 MPa but fail at 290 °C/7.35 MPa. The results indicate the difficulties of applying standard thick film technologies for sensor applications in a water/steam environment above 150 °C and imply the necessity of new technology and material developments for such applications.
Keywords: water/steam environment; thick film technology; autoclave storage; thermal anemometry sensor
Involved research facilities
- TOPFLOW Facility
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Lecture (Conference)
The 10th IEEE ESTC, 11.-13.09.2024, Berlin, BRD -
Contribution to proceedings
2024 IEEE 10th Electronics System-Integration Technology Conference (ESTC), 11.-13.09.2024, Berlin, BRD
2024 IEEE 10th Electronics System-Integration Technology Conference (ESTC): IEEE
DOI: 10.1109/ESTC60143.2024.10712069
Permalink: https://www.hzdr.de/publications/Publ-39142
Curvilinear magnetism: fundamentals and applications
Abstract
Curvilinear magnetism is a framework, which helps understanding the impact of geometric curvature on complex magnetic responses of curved 1D wires and 2D shells [1-3]. This approach provides means to modify conventional or to launch novel functionalities by tailoring curvature and 3D shape of magnetic thin films and nanowires [3,4]. In this talk, we will address fundamentals of curvature-induced effects in magnetism and review the envisioned application scenarios. In particular, we will demonstrate that curvature allows tailoring fundamental anisotropic and chiral magnetic interactions [5] and enables fundamentally new non-local chiral symmetry breaking effect [6,7]. 3D shaped magnetic objects enable realization of non-linear systems accommodating multiple solitons with complex interactions [8]. Those are relevant for numerous research and technology fields ranging from non-conventional computing and spin-wave splitters for low-energy magnonics. Application potential of geometrically curved magnetic architectures is currently being explored as mechanically reshapeable magnetic field sensors for automotive applications, spin-wave filters, high-speed racetrack memory devices, magnetic soft robotics [9] as well as on-skin interactive electronics relying on thin films [10-12] as well as printed magnetic composites [13,14] with appealing self-healing performance [15]. This opens perspectives for magnetoelectronics in smart wearables, interactive printed electronics and motivates further explorations towards the realization of eco-sustainable magnetic field sensing relying on biocompatible and biodegradable materials.
[1] P. Gentile et al., Electronic materials with nanoscale curved geometries. Nature Electronics (Review) 5 (2022) 551.
[2] P. Makushko et al., A tunable room-temperature nonlinear Hall effect in elemental bismuth thin films. Nature Electronics 7 (2024) 207.
[3] D. Makarov et al., New Dimension in Magnetism and Superconductivity: 3D and Curvilinear Nanoarchitectures. Advanced Materials (Review) 34 (2022) 2101758.
[4] D. Makarov et al., Curvilinear micromagnetism: from fundamentals to applications (Springer, Zurich, 2022).
[5] O. Volkov et al., Experimental observation of exchange-driven chiral effects in curvilinear magnetism. Physical Review Letters 123 (2019) 077201.
[6] D. D. Sheka et al., Nonlocal chiral symmetry breaking in curvilinear magnetic shells. Communications Physics 3 (2020) 128.
[7] O. M. Volkov et al., Chirality coupling in topological magnetic textures with multiple magnetochiral parameters. Nature Communications 14 (2023) 1491.
[8] O. Volkov et al., Three-dimensional magnetic nanotextures with high-order vorticity in soft magnetic wireframes. Nature Communications 15 (2024) 2193.
[9] M. Ha et al., Reconfigurable Magnetic Origami Actuators with On-Board Sensing for Guided Assembly. Advanced Materials 33 (2021) 2008751.
[10] G. S. Canon Bermudez et al., Magnetosensitive e-skins for interactive devices. Advanced Functional Materials (Review) 31 (2021) 2007788.
[11] J. Ge et al., A bimodal soft electronic skin for tactile and touchless interaction in real time. Nature Communications 10 (2019) 4405.
[12] G. S. Canon Bermudez et al., Electronic-skin compasses for geomagnetic field driven artificial magnetoception and interactive electronics. Nature Electronics 1 (2018) 589.
[13] M. Ha et al., Printable and Stretchable Giant Magnetoresistive Sensors for Highly Compliant and Skin-Conformal Electronics. Advanced Materials 33 (2021) 2005521.
[14] E. S. Oliveros Mata et al., Dispenser printed bismuth-based magnetic field sensors with non-saturating large magnetoresistance for touchless interactive surfaces. Advanced Materials Technologies 7 (2022) 2200227.
[15] R. Xu et al., Self-healable printed magnetic field sensors using alternating magnetic fields. Nature Communications 13 (2022) 6587.
Keywords: curvilinear magnetism; shapeable magnetoelectronics; printed magnetoelectronics; soft magnetic composites; Stimuli-responsive materials
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 39141) publication
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Invited lecture (Conferences)
10th International Conference on Materials Science and Condensed Matter Physics, 01.-04.10.2024, Chișinău, Moldova
Permalink: https://www.hzdr.de/publications/Publ-39141
Improvement of Single-Crystal Structures of Very Heavy Element Compounds by Refining Anomalous Dispersion Parameters
Meurer, F.; Morrison, G.; Hischa, B.; Zur Loye, H.-C.; Hennig, C.; Bodensteiner, M.
Abstract
In this work, we have demonstrated the ability to perform anomalous dispersion refinements for very heavy elements in the energy range of their L absorption edges using four different uranium compounds as examples. The ADR’s f’’ followed the independently recorded X-ray absorption spectra closely, even in the delicate edge region. In the case of Cs2(UO2)Ti2O6, which contains two crystallographically independent but chemically identical uranium positions, the deviation of f’ and f’’ for both positions is negligible. This shows the promising possibility of observing individual dispersion parameters for spatially and possibly chemically different elements using single-crystal X-ray diffraction at different energies. We have also shown that the treatment of the anomalous dispersion as a free parameter also leads to an improvement in the structure models of measurements with the laboratory diffractometer further away from the absorption edges. The published structures of the four compounds subject to this study, measured at an in-house diffractometer using the common Mo Kα radiation, could be improved by applying ADR.
Involved research facilities
- Rossendorf Beamline at ESRF DOI: 10.1107/S1600577520014265
Related publications
- DOI: 10.1107/S1600577520014265 is cited by this (Id 39140) publication
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Inorganic Chemistry 63(2024)34, 15784-15790
DOI: 10.1021/acs.inorgchem.4c01772
Cited 1 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39140
Experimental observation of repulsively bound magnons
Wang, Z.; Halati, C.-M.; Bernier, J.-S.; Ponomaryov, O.; Gorbunov, D.; Niesen, S.; Breunig, O.; Klopf, J. M.; Zvyagin, S.; Lorenz, T.; Loidl, A.; Kollath, C.
Abstract
Stable composite objects (e.g. hadrons, nuclei, atoms, molecules, and superconducting pairs) formed by attractive forces are ubiquitous in nature. In contrast, composite objects stabilized via repulsive forces were long thought to be theoretical constructions due to their fragility in naturally occurring systems. Surprisingly, the formation of bound atom pairs by strong repulsive interactions has been demonstrated experimentally in optical lattices1. Despite this success, repulsively bound particle pairs were believed to have no analogue in condensed matter due to strong decay channels. Here, we present spectroscopic signatures of repulsively bound three-magnon states and bound magnon pairs, in the Ising-like chain antiferromagnet BaCo2V2O8. In large transverse fields, below the quantum critical point, we identify repulsively bound magnon states by comparing terahertz spectroscopy measurements to theoretical results for the Heisenberg-Ising chain antiferromagnet, a paradigmatic quantum many-body model2–5. Our experimental results show that these high-energy repulsively bound magnon states are well separated from continua, exhibit significant dynamical responses and, despite dissipation, are sufficiently long-lived to be identified. As the transport properties in spin chains can be altered by magnon bound states, we envision such states could serve as resources for magnonics based quantum information processing technologies6–8.
Keywords: magnon; THz spectroscopy; FEL; FELBE; spin; EPR; HLD-EMFL; pulsed magnetic field; antiferomagnetic
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- High Magnetic Field Laboratory (HLD)
- F-ELBE
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 39139) publication
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Nature 631(2024), 760-764
DOI: 10.1038/s41586-024-07599-3
Cited 1 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39139
High quantum efficiency magnisum photocathode for photoinjectors
Xiang, R.; Schaber, J.; Teichert, J.; Arnold, A.; Murcek, P.; Niemczyk, R.; Ryzhov, A.
Abstract
To improve the quality of photocathodes is one of the critical issues in enhancing the stability and reliability of photo-injector systems. Magnesium has a low work function (3.6 eV) and shows high quantum efficiency (QE) after proper surface cleaning. This paper presents the investigation of alternative surface cleaning procedures, such as ps laser cleaning, thermal cleaning and ion beam cleaning. The QE is able to be improved two magnitudes after the treatment.
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- Superconducting Electron Linear Accelerator
- SRF Gun
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 39138) publication
-
Lecture (Conference)
87. Jahrestagung der DPG und DPG-Frühjahrstagung der Sektion Kondensierte Materie (SKM) 2024, 17.-22.03.2024, Berlin, Germany
Permalink: https://www.hzdr.de/publications/Publ-39138
Partilce-free cathode transfer system for SRF photoinjector
Xiang, R.; Gatzmaga, S.; Murcek, P.; Steinbrueck, R.; Teichert, J.; Arnold, A.; Hoffmann, A.
Abstract
Superconducting radio frequency (SRF) photoinjectors offer advantages for continuous wave (CW) operation and high brightness, high current beam generation. One of the critical components for successful operation of SRF photoinjectors is the photocathode system. HZDR is building a sophisticated cathode exchange system to ensure accurate, particle-free and warm cathode exchange. A novel alignment process aligns the cathode to the gun axis without touching the cathode plug itself. Less than 10 particles as small as 0.3 micrometer are detected
during the cathode load-lock tests.
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- Superconducting Electron Linear Accelerator
- SRF Gun
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 39137) publication
-
Lecture (Conference)
87. Jahrestagung der DPG und DPG-Frühjahrstagung der Sektion Kondensierte Materie (SKM) 2024, 17.-22.03.2024, Berlin, Germany
Permalink: https://www.hzdr.de/publications/Publ-39137
Thin Film Lithium-Ion Battery Based on Copper Silicon Anode
Cherkouk, C.; Weigel, T.; Köhler, T.; Stöcker, H.; Ferch, M.; Hahn, R.; Delan, A.; Folgner, C.; Zhou, S.; Rebohle, L.
Abstract
Ongoing miniaturization down to a few nanometers will lead to further significant
reductions in the power consumption of microchips and sensors. The number of
innovative applications immediately arise from the potential of integrating a
microbattery as a power source for flexible electronics, wearables, the Internet of
Things, medical implants and sensor chips.
In this work, a thin film lithium-Ion battery (TF-LIB) is demonstrated. The TF-LIB consists
of a high potential copper silicide anode (CuSi-anode) that can be integrated on a Siwafer
with standard semiconductor technology and a hybrid polymer electrolyte with a
high lithium-ion transference number. Two cathode materials were tested: LiFePO4 and
NCA.
The CuSi-anode is fabricated by Si sputtering followed by flash lamp annealing (FLA).
This anode material replaces metallic lithium for reaching high energy densities and
provides the thermal stability required in microelectronics (> 230 °C for soldering).
The hybrid polymer electrolyte is mechanically stable against the volume change of the
silicon during the lithiation/ delithiathion processes. The electrolyte is unreactive and
thermally stable at high temperatures during operation.
Keywords: Battery; Copper silicide anode; Polymer electrolyte; Thin film battery; All-solid-state battery; Integration on Si-Wafer
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 39136) publication
-
Poster
Advanced Automotive Battery Conference Europe, 13.-16.05.2024, Straßburg, Frankreich
Permalink: https://www.hzdr.de/publications/Publ-39136
Seasonal energy and carbon dioxide geological storage by means of novel electrothermal energy storage system
Carro, A.; Ortiz, C.; Unger, S.; Fogel, S.; Antoniadou, I.; Becerra, J. A.; Chacartegui, R.
Abstract
Implementing large-scale energy storage systems constrains the massive deployment of renewable energy production today. These systems must be capable of providing coverage for seasonal lag, as well as the daily mismatch between renewable energy availability and energy demand. This work evaluates the potential of a novel CO2-based electrothermal energy and geological storage (CEEGS) system. Its operating principle is that of a reversible heat pump based on transcritical CO2 cycles, which simultaneously allow the storage/production of renewable energy and the storage of CO2 within underground geological formations. A study of the CEEGS system's capacity to integrate into regional or national energy systems is developed. The CEEGS system is proposed as a viable alternative to provide large PV power plants with production flexibility and dispatchable energy. The feasibility of the concept is demonstrated under a scenario of fluctuating production within a year in the Spanish national framework of the Iberian Peninsula's energy system.
Involved research facilities
- TOPFLOW Facility
- ROFEX
-
Lecture (Conference)
37th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, 30.06.-05.07.2024, Rhodos, Griechenland -
Contribution to proceedings
37th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, 30.06.-05.07.2024, Rhodos, Griechenland
Permalink: https://www.hzdr.de/publications/Publ-39135
Glycolic acid and D-lactate—putative products of DJ-1— restore neurodegeneration in FUS - and SOD1-ALS
Pal, A.; Grossmann, D.; Glaß, H.; Zimyanin, V.; Günther, R.; Catinozzi, M.; Boeckers, T. M.; Sterneckert, J.; Storkebaum, E.; Petri, S.; Wegner, F.; Grill, S. W.; Pan-Montojo, F.; Hermann, A.
Abstract
Amyotrophic lateral sclerosis (ALS) leads to death within 2–5 yr. Currently, available drugs only slightly prolong survival. We present novel insights into the pathophysiology of Superoxide Dismutase 1 (SOD1)- and in particular Fused In Sarcoma (FUS)-ALS by revealing a supposedly central role of glycolic acid (GA) and D-lactic acid (DL)— both putative products of the Parkinson’s disease associated glyoxylase DJ-1. Combined, not single, treatment with GA/DL restored axonal organelle phenotypes ofmitochondria and lysosomes in FUS- and SOD1-ALS patient-derived motoneurons (MNs). This was not only accompanied by restoration of mitochondrial membrane potential but even dependent on it. Despite presenting an axonal transport deficiency as well, TDP43 patient-derived MNs did not share mitochondrial depolarization and did not respond to GA/DL treatment. GA and DL also restored cytoplasmic mislocalization of FUS and FUS recruitment to DNA damage sites, recently reported being upstream of the mitochondrial phenotypes in FUS-ALS. Whereas these data point towards the necessity of individualized (gene-) specific therapy stratification, it also suggests common therapeutic targets across different neurodegenerative diseases characterized by mitochondrial depolarization.
Involved research facilities
- High Magnetic Field Laboratory (HLD)
-
Life Science Alliance 7(2024), e202302535
DOI: 10.26508/lsa.202302535
Downloads
Permalink: https://www.hzdr.de/publications/Publ-39134
A contribution to understanding ion-exchange mechanisms for lithium recovery from industrial effluents of lithium-ion battery recycling operations
Salces, A. M.; Kelly, N.; Streblow, G. J.; Temel, E. T.; Rudolph, M.; Chagnes, A.; Vanderbruggen, A.
Abstract
Industrial effluents or process waters generated from spent lithium-ion batteries (LIBs) recycling operations often contain high concentrations of lithium ions (Li+). This study characterizes the composition of process water obtained from pre-treatment and concentration operations of LIBs recycling. Ion-exchange experiments are conducted using synthetic lithium solutions (1 g/L) and industrial waters to understand Li+ recovery. Employing four commercial cationic resins, fast Li+ exchange kinetics are observed fitting the pseudo-second order model. The equilibrium isotherm data corresponds to the Langmuir adsorption model and reveals a Li capacity of 30 32 mg/g using AmberliteTM IRC 120 H, 70 mg/g using Lewatit® TP 308 H, 37 40 mg/g using Lewatit® TP 208 Na, and 37-41 mg/g using Lewatit® TP 260 Na. While the resins initially demonstrate moderate affinity for Li+, this can be significantly enhanced by increasing the Li+ concentration. Notably, as LIBs recycling operation effluents typically contain minimal competing ions, these results underscore the potential of employing ion exchange as a viable method to recover and concentrate lithium before precipitation into lithium salts.
Keywords: lithium-ion batteries recycling; direct lithium extraction; ion exchange; water re-use
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Journal of Environmental Chemical Engineering 12(2024)3, 112951
DOI: 10.1016/j.jece.2024.112951
Cited 7 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39133
Investigating the Multidimensional Separation Behavior of Particles in a Cyclosizer Setting - A Case Study on Calcite, Fluorite and Magnesite
Sygusch, J.; Wilhelm, T.; Furat, O.; Schmidt, V.; Rudolph, M.
Abstract
Particle separation is typically investigated regarding one particulate property only. Virtually all separation processes, however, act on various particle properties in different ways. Modern particle analytical modalities enable a statistically meaningful multidimensional particle characterization. Within this study, individual particle fractions of magnesite, calcite and fluorite (-71 μm) are processed via the turbulent cross-flow separator cascade Cyclosizer (M16, MARC Technologies Pty Ltd), consisting of 5 hydrocyclones, thus producing 5 different product streams. Particle characterization is achieved via dynamic image analysis from which information on the particle shape and size is obtained. Using this data, bivariate Tromp functions are computed, which show the combined effect of the particle descriptors of roundness and area-equivalent diameter on the separation behavior. While the first cyclones recover predominantly coarse particles with high roundness values, fine particles with varying roundness are recovered in the latter cyclones.
Keywords: Hydrocyclone; multidimensional separation; multivariate Tromp function; particle size; particle shape
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Contribution to proceedings
XXXI IMPC-International Mineral Processing Congress, 29.09.-03.10.2024, Washington, DC, United States, 978-0-87335-518-6 -
Lecture (Conference)
XXXI IMPC-International Mineral Processing Congress, 29.09.-03.10.2024, Washington, DC, United States
Permalink: https://www.hzdr.de/publications/Publ-39132
Momentum space separation of quantum path interferences between photons and surface plasmon polaritons in nonlinear photoemission microscopy
Dreher, P.; Janoschka, D.; Giessen, H.; Schützhold, R.; Davis, T. J.; Horn-Von Hoegen, M.; Meyer Zu Heringdorf, F.-J.
Abstract
Quantum path interferences occur whenever multiple equivalent and coherent transitions result in a common final state. Such interferences strongly modify the probability of a particle to be found in that final state, a key concept of quantum coherent control. When multiple nonlinear and energy-degenerate transitions occur in a system, the multitude of possible quantum path interferences is hard to disentangle experimentally. Here, we analyze quantum path interferences during the nonlinear emission of electrons from hybrid plasmonic and photonic fields using time-resolved photoemission electron microscopy.We experimentally distinguish quantum path interferences by exploiting the momentum difference between photons and plasmons and through balancing the relative contributions of their respective fields. Our work provides a fundamental understanding of the nonlinear photon–plasmon–electron
interaction. Distinguishing emission processes in momentum space, as introduced here, could allow nano-optical quantum-correlations to be studied without destroying the quantum path interferences.
Keywords: PEEM; surface plasmon polaritons; photoemission
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Contribution to WWW
https://arxiv.org/abs/2310.11936
DOI: 10.48550/arXiv.2310.11936
arXiv: 10.48550/arXiv.2310.11936 -
Nanophotonics 13(2024)9, 1593-1602
DOI: 10.1515/nanoph-2023-0776
Cited 1 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39131
Searching for axion resonances in vacuum birefringence with three-beam collisions
Abstract
We consider birefringent (i.e., polarization changing) scattering of x-ray photons at the superposition of two optical laser beams of ultrahigh intensity and study the resonant contributions of axions or axionlike particles, which could also be short lived. Applying the specifications of the Helmholtz International Beamline for Extreme Fields (HIBEF), we find that this setup can be more sensitive than previous light-bylight scattering (birefringence) or light-shining-through-wall experiments in a certain domain of parameter space. By changing the pump and probe laser orientations and frequencies, one can even scan different axion masses, i.e., chart the axion propagator.
-
Contribution to WWW
https://arxiv.org/abs/2307.08345
DOI: 10.48550/arXiv.2307.08345
arXiv: https://doi.org/10.48550/arXiv.2307.08345 -
Physical Review D 109(2024)L091901
DOI: 10.1103/PhysRevD.109.L091901
Cited 2 times in Scopus
Downloads
Permalink: https://www.hzdr.de/publications/Publ-39130
Temperature-Dependent Characteristics of GeSn Waveguide p-i-n Photodetectors: Step Towards Cryogenic Silicon Photonics
Bansal, R.; Jheng, Y.-T.; Lee, K.-C.; Wen, S.; Berencen, Y.; Cheng, H.-H.; Chang, G.-E.
Abstract
This dataset is for noise equivalent power measurements of different GeSn photodetectors
Keywords: GeSn; Photodetectors; Noise
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Reseach data in the HZDR data repository RODARE
Publication date: 2024-05-23 Open access
DOI: 10.14278/rodare.2885
Versions: 10.14278/rodare.2886
License: CC-BY-4.0
Downloads
Permalink: https://www.hzdr.de/publications/Publ-39129
Data publication: Effect of Helium Ion Implantation on 3C-SiC Nanomechanical String Resonators
Bredol, P.; David, F.; Jagtap, N.; Astakhov, G.; Erbe, A.; Weig, E. M.; Klaß, Y.
Abstract
The file "figures.hdf5" contains all numbers plotted in the figures of the main manuscript. Each entry in the first hierarchy level of the file, e.g. "Figure 2a", corresponds to one subfigure. Each entry in the second hierarchy level (if existent) corresponds to one of the curve/subset of the the respective figure, e.g. if curves for multiple fluences are plotted. The innermost hierarchy level contains the data arrays. The dataset name corresponds to the axis label and units. The file "analyzed.hdf5" contains frequencies, quality factors, stress and Young's modulus fit results for each measured nanostring device on each measured sample. The first hierarchy level represents the sample (A or B). The second hierarchy level represents the accumulated implantation fluence that the sample has seen before the respective measurements. The third hierarchy level represents the write field, i.e. string array index, on the chip (0-3) and the fourth hierarchy level represents the string length within the write field. Each length exists exactly once in each write field. The innermost hierarchy level contains arrays of mode number, frequency, quality factor and "raw data indices" (see next paragraph) representing each measured resonance. The fields Young's modulus and pre-stress are scalars containing the respective fit result and its uncertainty. The file "raw.hdf5" finally contains all raw spectra. The first hierarchy level corresponds to unique indices of the respective measurement. This is intended as a look up table for the "raw data indices" of the "analyzed.hdf5" file. Using the index found in the "analyzed.hdf5", one can obtain the raw frequency sweep data and metadata. The file "srim-VACANCY.txt" is the vacancy output file of the SRIM simulation discussed in the main manuscript.
Keywords: nanomechanics; defects; ion beam irradiation; quantum sensors
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 39128) publication
- DOI: 10.1103/PhysRevApplied.22.034036 references this (Id 39128) publication
-
Effect of Helium Ion Implantation on 3C-SiC Nanomechanical String Resonators
ROBIS: 38866 has used this (Id 39128) publication of HZDR-primary research data
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Reseach data in the HZDR data repository RODARE
Publication date: 2024-06-17 Open access
DOI: 10.14278/rodare.3023
Versions: 10.14278/rodare.3024
License: CC-BY-4.0
Downloads
Permalink: https://www.hzdr.de/publications/Publ-39128
Organic/metallic component analysis of lignocellulosic biomass: A thermochemical-perspective-based study on rice and bamboo waste
Kachroo, H.; Verma, V. K.; Doddapaneni, T. R. K. C.; Kaushal, P.; Jain, R.
Abstract
Thermochemical treatment is significantly impacted by the physiochemical properties of lignocellulosic biomass. Traditional characterization methods lack granularity, requiring advanced analytical techniques for comprehensive biomass characterization. This study analyzed elemental composition and their distribution in untreated rice husk, rice straw, and bamboo chips at micron and sub-micron scales. Results reveal significant variations in composition and spatial distribution of metallic components among agro-residues. Thermogravimetric analysis shows divergent decomposition patterns, while spectroscopic analysis indicates structural complexities and distinct silica content. Surface mapping illustrates prevalent silica and alkali metals on rice husk and rice straw. Atomic force microscopy depicts distinctive surface morphologies, with rice straw exhibiting heightened roughness due to silica bodies. Inductively coupled plasma-mass-spectrometry identified the abundance of alkali and alkaline earth metals in rice waste. Time-of-flight secondary ion mass spectrometry elucidates elemental spatial localization, affirming heterogeneous distribution across rice waste and homogenous distribution across bamboo waste. This study bridges the gap between biomass composition and optimized thermochemical conversion outcomes.
Keywords: Lignocellulosic biomass; Biomass characterization; Comparative biomass study; Tof-SIMS; Inorganics distribution
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Bioresource Technology 403(2024), 130835
DOI: 10.1016/j.biortech.2024.130835
Cited 3 times in Scopus
Downloads
Permalink: https://www.hzdr.de/publications/Publ-39126
SAPPHIRE - Establishment of Small Animal Proton and PHoton Image-guided Radiation Experiments
Schneider, M.; Schilz, J.; Schürer, M.; Gantz, S.; Dreyer, A.; Rothe, G.; Tillner, F.; Bodenstein, E.; Horst, F. E.; Beyreuther, E.
Abstract
The in vivo evolution of radiotherapy necessitates innovative platforms for preclinical investigation, bridging the gap between bench research and clinical applications. Understanding the nuances of radiation response, specifically tailored to proton and photon therapies, is critical for optimizing treatment outcomes. Within this context, preclinical in vivo experimental setups incorporating image guidance for both photon and proton therapies are pivotal, enabling the translation of findings from small animal models to clinical settings. The SAPPHIRE project represents a milestone in this pursuit, presenting the installation of the small animal radiation therapy integrated beamline (SmART+ IB, Precision X-Ray Inc., Madison, Connecticut, USA) designed for preclinical image-guided proton and photon therapy experiments at University Proton Therapy Dresden. Through Monte Carlo simulations, low-dose on-site cone beam computed tomography imaging and quality assurance alignment protocols, the project ensures the safe and precise application of radiation, crucial for replicating clinical scenarios in small animal models. The creation of Hounsfield lookup tables and comprehensive proton and photon beam characterizations within this system enable accurate dose calculations, allowing for targeted and controlled comparison experiments. By integrating these capabilities, SAPPHIRE bridges preclinical investigations and potential clinical applications, offering a platform for translational radiobiology research and cancer therapy advancements.
Keywords: Proton therapy; Image-guided mouse irradiation; Preclinical (in vivo) studies; Relative biological effectiveness (RBE)
Involved research facilities
- OncoRay
Related publications
-
Data publication: SAPPHIRE - Establishment of small animal proton and photon …
ROBIS: 37852 HZDR-primary research data are used by this (Id 39125) publication -
Data publication: SAPPHIRE - Establishment of small animal proton and photon …
RODARE: 2645 HZDR-primary research data are used by this (Id 39125) publication
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Physics in Medicine and Biology 69(2024)97, 095020
DOI: 10.1088/1361-6560/ad3887
ISSN: 00319155
Cited 1 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39125
MRI turbulence in vertically stratified accretion discs at large magnetic Prandtl numbers
Held, L.; Mamatsashvili, G.; Pessah, M. E.
Abstract
The discovery of the first binary neutron star merger, GW170817, has spawned a plethora of global numerical relativity simulations. These simulations are often ideal (with dissipation determined by the grid) and/or axisymmetric (invoking ad hoc mean-field dynamos). However, binary neutron star mergers (similar to X-ray binaries and active galactic nuclei inner discs) are characterized by large magnetic Prandtl numbers, Pm, (the ratio of viscosity to resistivity). Pm is a key parameter determining dynamo action and dissipation but it is ill-defined (and likely of order unity) in ideal simulations. To bridge this gap, we investigate the magnetorotational instability (MRI) and associated dynamo at large magnetic Prandtl numbers using fully compressible, three-dimensional, vertically stratified, isothermal simulations of a local patch of a disc. We find that, within the bulk of the disc (z ≲ 2H, where H is the scale-height), the turbulent intensity (parametrized by the stress-to-thermal-pressure ratio α), and the saturated magnetic field energy density, Emag, produced by the MRI dynamo, both scale as a power with Pm at moderate Pm (4 ≲ Pm ≲ 32): Emag ~ Pm0.74 and α ~ Pm0.71, respectively. At larger Pm (≳ 32), we find deviations from power-law scaling and the onset of a plateau. Compared to our recent unstratified study, this scaling with Pm becomes weaker further away from the disc mid-plane, where the Parker instability dominates. We perform a thorough spectral analysis to understand the underlying dynamics of small-scale MRI-driven turbulence in the mid-plane and of large-scale Parker-unstable structures in the atmosphere.
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Monthly Notices of the Royal Astronomical Society 530(2024)2, 2232-2250
DOI: 10.1093/mnras/stae929
arXiv: arXiv:2310.00453
Cited 3 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39124
Lane formation in gravitationally driven colloid mixtures consisting of up to three different particle sizes
Hofmann, K.; Isele, M.; Erbe, A.; Leiderer, P.; Nielaba, P.
Abstract
Brownian dynamics simulations are utilized to study segregation phenomena far from thermodynamic
equilibrium. In the present study, we expand upon the analysis of binary colloid mixtures
and additionally introduce a third particle species to further our understanding of colloidal
systems. Gravitationally driven, spherical colloids immersed in an implicit solvent are confined
in two-dimensional linear microchannels. The interaction between the colloids is modeled by the
Weeks-Chandler-Andersen potential, and the confinement of the colloids is realized by hard walls
based on the solution of the Smoluchowski equation in half space. In binary and ternary colloidal
systems, a difference in the driving force is achieved by differing colloid sizes, but fixed mass density.
We observe for both the binary and ternary systems that a driving force difference induces
a nonequilibrium phase transition to lanes. For ternary systems, we study the tendency of lane
formation in dependence of the diameter of the medium-sized colloids. Here, we find a sweetspot for
lane formation in ternary systems. Furthermore, we study the interaction of two differently sized
colloids at the channel walls. Recently, we observed that driven large colloids push smaller colloids
to the walls. This results in small particle lanes at the walls at early simulation times. In this work,
we additionally find that thin lanes are unstable and dissolve over very long time frames. Furthermore,
we observe a connection between lane formation and the nonuniform distribution of particles
along the channel length. This nonuniform distribution occurs either alongside lane formation or in
shared lanes (i.e. lanes consisting of two colloid types).
Keywords: colloids; colloidal model systems; molecular dynamics simulations
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 39123) publication
-
Physical Review E 109(2024)6, 064601
DOI: 10.1103/PhysRevE.109.064601
Downloads
Permalink: https://www.hzdr.de/publications/Publ-39123
Miniaturized Variable Stiffness Gripper Locally Actuated by Magnetic Fields
Masjosthusmann, L.; Richter, M.; Makushko, P.; Makarov, D.; Misra, S.
Abstract
In minimally invasive surgery, grippers are essential for tissue manipulation. However, in commercial tendon-driven systems, challenges remain, including tendon fatigue and bulkiness. Promising alternatives are magnetically actuated systems, offering contactless steering but limited forces. To overcome this, a miniaturized, locally actuated magnetic gripper with variable stiffness is presented. The gripper employs thin planar coils (75 μm) and a radially magnetized plunger, enabling local actuation and enhanced orientation control. The variable stiffness compliant mechanism made from shape-memory polymer facilitates different gripping strategies. In its rigid state, pulsed pulling forces of 340 mN and continuous forces of 90 mN are achieved, exceeding the gripper weight by factors of 70 and 18, respectively. The soft state, with a fast response time of 20 ms, enables soft gripping of various targets, including moving ones and rat tissue samples. Demonstrating the applicability, contactless steering and target retrieval within a stomach phantom is showcased. This study introduces promising improvements to magnetically actuated grippers for surgical procedures, addressing key challenges in current designs.
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Advanced Intelligent Systems 6(2024), 2400037
DOI: 10.1002/aisy.202400037
Cited 1 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39122
Maximising the value of hyperspectral drill core scanning through real-time processing and analysis
Thiele, S. T.; Kirsch, M.; Lorenz, S.; Saffi, H.; El Alami, S.; Cecilia Contreras Acosta, I.; Madriz Diaz, Y. C.; Gloaguen, R.
Abstract
Hyperspectral imaging is gaining widespread use in the resource sector, with applications in mineral exploration, geometallurgy and mine mapping. However, the sheer size of many hyperspectral datasets (> 1 Tb) and associated correction, visualisation and analysis challenges can limit the integration of this technique into time-critical exploration and mining workflows. In this contribution, we propose and demonstrate a novel open-source workflow for rapidly processing hyperspectral data acquired on exploration drillcores. The resulting products are adaptable to the varied needs of geologists, geophysicists and geological engineers, facilitating better integration of hyperspectral data during decision making. These tools are applied to process hyperspectral data of 6.4 km of exploration drill cores from Stonepark (Ireland), Collinstown (Ireland) and Spremberg (Germany). The results are presented via an open-source web-viewing platform that we have developed to facilitate easy on and off-site access to hyperspectral data and its derivatives. We suggest that maximum value can be extracted from hyperspectral data if it is acquired shortly after drilling and processed on-site in real time, so that results can be quickly validated and used to inform time-critical decisions on sample selection, geological interpretation (logging) and drillhole continuation or termination. This timeliness and accessibility is key to ensure rapid data availability for decision makers during mineral exploration and exploitation. Finally, we discuss several remaining challenges that limit the real-time integration of hyperspectral drill core scanning data, and explore some opportunities that may arise as these rich datasets become more widely collected.
Keywords: big data; core logging; minerals exploration; sediment hosted copper; sediment hosted Pb-Zn; kupferschiefer; irish type deposit; visualisation
Related publications
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Stonepark Hyperspectral Drillcore Data
ROBIS: 39102 is documented by this (Id 39121) publication -
Collinstown Hyperspectral Drillcore Data
ROBIS: 39108 is documented by this (Id 39121) publication -
Stonepark Hyperspectral Drillcore Data
RODARE: 2868 is documented by this (Id 39121) publication -
Collinstown Hyperspectral Drillcore Data
RODARE: 2864 is documented by this (Id 39121) publication -
Stonepark Hyperspectral Drillcore Data
ROBIS: 39102 HZDR-primary research data are used by this (Id 39121) publication -
Stonepark Hyperspectral Drillcore Data
RODARE: 2868 HZDR-primary research data are used by this (Id 39121) publication
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Frontiers in Earth Science 12(2024), 1433662
DOI: 10.3389/feart.2024.1433662
Permalink: https://www.hzdr.de/publications/Publ-39121
Is Julia ready to be adopted by HEP?
Gál, T.; Gras, P.; Hegner, B.; Hernandez Acosta, U.; Kluth, S.; Ling, J.; Moreno, A.; Pivarski, J.; Schulz, O.; Stewart, G.; Strube, J.; Vasilev, V.
Abstract
The Julia programming language was created 10 years ago and is now a mature and stable language with a large ecosystem including more than 8,000 third-party packages. It was designed for scientific programming to be a high-level and dynamic language as Python is, while achieving runtime performances comparable to C/C++ or even faster. With this, we ask ourselves if the Julia language and its ecosystem is ready now for its adoption by the High Energy Physics community. We will report on a number of investigations and studies of the Julia language that have been done for various representative HEP applications, ranging from computing intensive initial data processing of experimental data and simulation, to final interactive data analysis and plotting. Aspects of collaborative code development of large software within a HEP experiment has also been investigated: scalability with large development teams, continuous integration and code test, code reuse, language interoperability to enable an adiabatic migration of packages and tools, software installation and distribution, training of the community, benefit from development from industry and academia from other fields.
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Contribution to proceedings
26th International Conference on Computing in High Energy and Nuclear Physics (CHEP 2023), 08.-12.05.2023, Norfolk, VA, United States
DOI: 10.1051/epjconf/202429505008
Permalink: https://www.hzdr.de/publications/Publ-39120
Critical behavior of the dimerized Si(001) surface: Continuous order-disorder phase transition in the two-dimensional Ising universality class
Brand, C.; Hucht, A.; Mehdipour, H.; Jnawali, G.; Fortmann, J. D.; Tajik, M.; Hild, R.; Sothmann, B.; Kratzer, P.; Schützhold, R.; Horn-Von Hoegen, M.
Abstract
The critical behavior of the order-disorder phase transition in the buckled dimer structure of the Si(001) surface is investigated both theoretically by means of first-principles calculations and experimentally by spot profile analysis low-energy electron diffraction (SPA-LEED). We use density functional theory (DFT) with three different functionals commonly used for Si to determine the coupling constants of an effective lattice Hamiltonian describing the dimer interactions. Experimentally, the phase transition from the low-temperature c(4×2)- to the high-temperature p(2×1)-reconstructed surface is followed through the intensity and width of the superstructure spots within the temperature range 78–400K. Near the critical temperature Tc = 190.6K, we observe universal critical behavior of spot intensities and correlation lengths, which falls into the universality class of the two-dimensional (2D) Ising model. From the ratio of correlation lengths along and across the dimer rows we determine effective nearest-neighbor couplings of an anisotropic 2D Ising model,
J = (−24.9 ± 0.9stat ± 1.3sys )meV and J⊥ = (−0.8 ± 0.1stat )meV.We find that the experimentally determined coupling constants of the Ising model can be reconciled with those of the more complex lattice Hamiltonian
from DFT when the critical behavior is of primary interest. The anisotropy of the interactions derived from the
experimental data via the 2D Ising model is best matched by DFT calculations using the PBEsol functional.
The trends in the calculated anisotropy are consistent with the surface stress anisotropy predicted by the
DFT functionals, pointing towards the role of surface stress reduction as a driving force for establishing the
c(4×2)-reconstructed ground state.
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Contribution to WWW
https://arxiv.org/abs/2310.10488
arXiv: 10.48550/arXiv.2310.10488 -
Physical Review B 109(2024)
DOI: 10.1103/PhysRevB.109.134104
Cited 3 times in Scopus
Downloads
Permalink: https://www.hzdr.de/publications/Publ-39119
A framework for validating efficiency models of thermal separation col-umns with tray internals
Vishwakarmaa, V.; Marchini, S.; Schleicher, E.; Schubert, M.; Hampel, U.
Abstract
Tray columns are globally used for distillation processes, and their performance must be optimized to reduce their cost and energy expenditures as well as carbon emissions. A prerequisite to achieve these targets demands a realistic account of the tray performance based on tray efficiency model applica-tion. The proof of concept of a Refined Residence Time Distribution (RRTD) model, recently proposed by the authors, is presented. The multifaceted challenges in acquiring hydrodynamic and perfor-mance data suitable for model validation are discussed in this work. In that regard, an unprecedented experimental campaign was performed in a representative large-scale air-water tray column simula-tor based on the application of multiplex flow profiler, new chemical system, and novel data pro-cessing schemes. Using these data and additional case studies, the capabilities of the RRTD model were demonstrated. This model successfully accounted for the impacts of varying local liquid flow characteristics and vapor flow maldistributions on the tray efficiency thereby advancing the state of the art of the tray efficiency models. This work particularly aimed at proposing a constructive framework for evaluating tray efficiency models in the future campaigns, and those campaigns will benefit from the learnings of the present work.
Keywords: tray column; Murphree efficiency; mathematical model; residence time distribution; two-phase hydrodynamics; gas stripping
Related publications
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Hydrodynamic and efficiency data pertaining to an air-water column mockup (of …
ROBIS: 32942 HZDR-primary research data are used by this (Id 39118) publication -
Hydrodynamic and efficiency data pertaining to an air-water column mockup (of …
RODARE: 1072 HZDR-primary research data are used by this (Id 39118) publication
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Chemical Product and Process Modeling (2025)
Online First (2024) DOI: 10.1515/cppm-2024-0037
Permalink: https://www.hzdr.de/publications/Publ-39118
Formulation and application assessment of lignin-based biodegradable composite mulching film with emphasis on lignin enhancement
Zhang, B.; Wang, G.; Sui, W.; Parvez, A. M.; Si, C.
Abstract
Utilization of plastic materials (e.g., polyethylene) in mulching film production has inevitably resulted in nondegradable
pollutants in soil, which accordingly promotes the development of biodegradable mulching film
industry. As a rich renewable, biodegradable aromatic polymer, Lignin exhibits great potential for fabricating
functional biodegradable composite mulching films. In recent years, composite mulching films containing lignin
have garnered more interest for both practical applications and fundamental research, but comprehensive reviews
detailing preparation and application of this rapidly developing composite are still limited. Herein, we
begin with a brief description about the processes used to prepare lignin-based biodegradable mulching film.
Furthermore, the design and application advances of lignin-based biodegradable mulching films are elaborated
based on the polymer materials used, including natural and synthetic biodegradable polymers. Finally, the
remaining challenges and future perspectives of lignin-based biodegradable mulching films are summarized. We
expect that this finding will shed light on the forthcoming research of lignin-based biodegradable mulching film,
and stimulate the development in this research area.
Keywords: Lignin valorization; Lignin-based biodegradable mulching film; Composite film; Application assessment
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Industrial Crops and Products 215(2024), 118634
DOI: 10.1016/j.indcrop.2024.118634
Cited 5 times in Scopus
Downloads
- Secondary publication expected from 04.05.2025
Permalink: https://www.hzdr.de/publications/Publ-39117
Effect of decorporation agents on the speciation of lanthanides and actinides in artificial biofluids of the human digestive system
Barkleit, A.; Friedrich, S.; Butscher, D.; Kretzschmar, J.; Drobot, B.; Stumpf, T.
Abstract
If radionuclides (RN) enter the food chain and are ingested by humans, they pose a potential health risk due to their radio- and chemotoxicity. In order to accurately assess the health risk after oral ingestion of RN in food and beverages and to apply effective decontamination methods, it is essential to understand the processes of (bio)chemistry and speciation of RN at the molecular level.
To minimize the health risk, decorporation agents, which are usually strong complexones, are used after the accidental incorporation of RN in order to increase excretion. To date, however, only the aminopolycarboxylate diethylenetriaminepentaacetic acid (DTPA) has been used commercially, although it is only effective for trivalent actinides. Alternative potential decorporation agents such as the hydroxypyridinone 3,4,3-LI-HOPO (HOPO) are being developed,1 but they are not yet ready for commercial use.
Our group experimentally investigated the speciation of trivalent lanthanides and actinides (Ln(III)/An(III)) as well as uranium (U(VI)) in model fluids of the digestive tract in the absence and presence of decorporation agents. This work is part of the German joint project "Speciation and transfer of radionuclides in the human organism with special consideration of decorporation agents (RADEKOR)".
The artificial biofluids saliva, gastric juice, pancreatic juice and bile were synthesized according to the international Unified Bioaccessibility Method (UBM) of the Bioaccessibility Research Group of Europe (BARGE).2 The solutions were spiked with the lanthanide Eu(III) as a non-radioactive analogue for trivalent actinides as well as the actinides Cm(III) and U(VI). Samples were analysed spectroscopically, mainly using time-resolved laser-induced luminescence spectroscopy (TRLFS). By analysing the spectra with parallel factor analysis (PARAFAC) and comparing them with the luminescence spectra of the individual components of the biofluids, we were able to determine the speciation of the metal ions in each biofluid. The results were confirmed and partially improved with NMR investigations.
Speciation studies for Eu(III) and Cm(III) in artificial biofluids resulted in variable coordination spheres with carbonate, phosphate and also some proteins such as α-amylase or mucin, depending on the composition of the biofluid.3 The complexation of U(VI) is mainly dominated by carbonate.
To investigate the impact of potential decorporation agents on the speciation of RN in the biofluids of the digestive system, distinct amounts of selected complexones were added to the solutions containing biofluid and metal and analysed as described. Beside DTPA as commercially used standard decorporation agent we investigated the recently developed and very promising complexone HOPO.1 Furthermore, we considered the diphosphonate etidronic acid (1-Hydroxyethylidene-1,1-diphosphonic acid, HEDP), which was already used as a pharmaceutical, and also alternative aminopolycarboxylates like ethylene diamine tetraacetic acid (EDTA) and ethylene glycol tetraacetic acid (EGTA).
The influence of the complexones on the speciation of metal ions varied. For Eu(III), for example, HOPO could displace the bioligands just as strongly as DTPA, while EDTA and EGTA had less effect. HEDP, on the other hand, is not suitable for trivalent actinides as it forms insoluble complexes at physiologically relevant pH.4 HOPO was also able to displace the very strong bioligand carbonate from the U(VI) coordination sphere, whereas HEDP, for example, only caused a change in the U(VI) species in the biofluids at much higher concentrations than HOPO.
The results of this work contribute to a better understanding of the effect of decorporation agents after RN incorporation at the molecular level and supports making them more effective.
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Lecture (Conference)
10th International Conference on Nuclear and Radiochemistry (NRC), 25.-30.08.2024, Brighton, United Kingdom
Permalink: https://www.hzdr.de/publications/Publ-39116
Automated one-pot two-step radiosynthesis of (S)-[18F]FETrp for PET imaging of indoleamine 2,3-dioxygenase 1 (IDO1)
Maisonial-Besset, A.; Kryza, D.; Kopka, K.; Moreau, E.; Wenzel, B.; Chezal, J.-M.
Abstract
(S)-1-(2-[18F]fluoroethyl)tryptophan ((S)-[18F]FETrp) is a promising PET radiotracer under clinical investigation for imaging indoleamine 2,3-dioxygenase 1 (IDO1) activity.1 IDO1 is one of the main enzymes involved in the tryptophan metabolism, and plays a significant role in several diseases, including cancers. To date, the radiosynthesis of this tryptophan analogue remains highly challenging due to partial racemization occurring during the nucleophilic radiofluorination step and subsequent complicated purification processes. These issues result in prolonged reaction times and low radiochemical yields, which could ultimately impede the widespread use of this radiotracer. In this study, we develop a short, epimerization-free and efficient automated procedure for the radiosynthesis of (S)-[18F]FETrp under “low base” radiofluorination conditions. To this end, enantiomerically pure (S)- and (R)-FETrp references as well as their corresponding (S)- and (R)-tosylate precursors were obtained from Na-Boc-(L/D)-tryptophan in 2 and 4 steps, respectively. Manual optimisation of the radiolabelling conditions using tetrabutylammonium [18F]fluoride resulted in >90% radiochemical conversion with more than 99% enantiomeric purity. Then, the (S)-[18F]FETrp radiosynthesis was fully automated on a SynChrom R&D EVOI module to produce the radiotracer in 55.2 ± 7.5% radiochemical yield, 99.9% radiochemical purity, 99.1 ± 0.5% enantiomeric excess, and molar activity of 53.2 ± 9.3 GBq/mol (n = 3). This optimised and robust production method could facilitate further investigations of this relevant PET radiotracer for imaging IDO1 activity.
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Poster
Premières journées communes des sections régionales Centre-Ouest et Auvergne, 27.-28.06.2024, Clermont-Ferrand, Frankreich
Permalink: https://www.hzdr.de/publications/Publ-39115
Investigation of radiation damage in the monazite-type solid solution La1-xCexPO4
Lender, T.; Murphy, G.; Bazarkina, E.; Bukaemskiy, A.; Gilson, S.; Henkes, M.; Hennig, C.; Kaspor, A.; Marquardt, J.; Nießen, J.; Peters, L.; Poonoosamy, J.; Roßberg, A.; Svitlyk, V.; Kvashnina, K.; Huittinen, N. M.
Abstract
Crystalline materials such as monazite have been considered for the storage of radionuclides due to their apparent radiation stability. Understanding their structural chemical response to radiation damage is a key component of determining their suitability for this application. Herein, high resolution structural studies were performed on the monazite solid solution La1-CexPO4 (x = 0.25, 0.5, 0.75, 1) in order to understand the role of structural chemistry on irradiation stability. Ceramic samples were irradiated with 14MeV Au ions with 1014 ions/cm2 and 1015 ions/cm2 to simulate the recoil of daughter nuclei from the alpha decay of actinides. The extent of radiation damage was analysed in detail using scanning electron microscopy
(SEM), Raman spectroscopy, grazing incidence X-ray diffraction (GI-XRD) and high-energy-resolution fluorescence detection extended X-ray absorption fine structure (HERFD-EXAFS) spectroscopy. SEM and Raman revealed extensive structural damage as well as the importance of grain boundary regions, which appear to impede the propagation of defects. Both radiation-induced amorphisation and recrystallisation were studied by grazing incidence X-ray diffraction, highlighting the exceptional ability of monazite to remain crystalline at high fluences throughout the solid solution. Both, diffraction and HERFD-EXAFS experiments show that while atomic disorder is increased in irradiated samples compared to pristine ceramics,
the short-range order was found to be largely preserved, facilitating recrystallisation. Crucially, this is consistent for all investigated samples, despite the chemical disorder introduced in the solid solution.
Keywords: Monazite; Irradiation; Raman spectroscopy; Grazing incidence X-ray diffraction; HERFD-EXAFS
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
- Rossendorf Beamline at ESRF DOI: 10.1107/S1600577520014265
Related publications
- DOI: 10.1107/S1600577520014265 is cited by this (Id 39114) publication
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 39114) publication
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Inorganic Chemistry 63(2024)38, 17525-17535
DOI: 10.1021/acs.inorgchem.4c02041
Cited 2 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39114
Mineralogy and mineral paragenesis of the Palaeoproterozoic manganese ores of the Avontuur deposit of the Kalahari Manganese Field, South Africa
Coetzee, L. L.; Gutzmer, J.; Smith, A. J. B.; Beukes, N. J.
Abstract
This study provides for the first time details of the mineralogy, petrography and mineral paragenetic relationships of manganese ores of the Avontuur deposit, a prominent northern outlier of the Kalahari Manganese Field in the Northern Cape Province of South Africa. Using a combination of light and electron microscopy and X-ray powder diffractometry on an extensive suite of exploration drill core samples, it is shown that the manganese ores comprise an exceptionally fine-grained assemblage of Mn2+-silicates (friedelite, tephroite, gageite), Mn2+/Mn3+-oxides (jacobsite, hausmannite) and Mn2+-carbonates (rhodochrosite, kutnahorite, Mn-dolomite and Mn-calcite). This mineral assemblage is a product of diagenesis and very low-grade regional metamorphism. Locally, this assemblage is overprinted by contact metamorphism or supergene alteration. Despite close geochemical and textural similarities, the manganese ores of the Avontuur deposit are surprisingly different in their mineralogy compared to the carbonate- and braunite-dominated mangano-lutites of the main Kalahari deposit. Distinctly higher concentrations of both SiO2and Fe2O3in the mangano-lutites of the Avontuur deposit as compared to the main Kalahari Deposit provide the reason for the markedly different mineralogy. Such marked differences in bulk chemistry are tentatively attributed to systematic lateral variations in the physicochemical conditions of mineral precipitation during the deposition of the Hotazel Formation.
Keywords: South Africa; Manganese; Paleoproterozoic; Mineralogy; Geology
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South African Journal of Geology 127(2024)1, 31-54
DOI: 10.25131/sajg.127.0016
Permalink: https://www.hzdr.de/publications/Publ-39113
Design of a contactless inductive flow tomography system for a large Rayleigh-Bénard convection cell with aspect ratio Γ = 0.5
Mitra, R.; Sieger, M.; Galindo, V.; Vogt, T.; Stefani, F.; Eckert, S.; Wondrak, T.
Abstract
Contactless inductive flow tomography (CIFT) is a flow measurement technique that is able to reconstruct the time-dependent three-dimensional velocity field in electrically conducting fluids, e.g., liquid metals, from magnetic field measurements. The paper describes the design of a specific CIFT measurement set-up for flow studies in liquid metal Rayleigh-Bénard convection (RBC) in a large cylinder of aspect ratio (diameter/height) of Γ = 0.5 filled with the ternary alloy GaInSn as model fluid. An optimized configuration for the CIFT excitation system and magnetic field sensor layout under consideration of the specific requirements for the application in turbulent RBC is determined by numerical simulations. The new experimental CIFT-RBC system resulting from the design process is constructed and a preliminary experiment at a Rayleigh number of Ra = 2.13 × 107 and a Prandtl number of Pr = 0.03 is performed and evaluated.
Keywords: Contactless inductive flow tomography; Rayleigh-Bénard convection; magnetic field measurement; three-dimensional velocity reconstruction; inverse problem; liquid metal flows
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Flow Measurement and Instrumentation 100(2024), 102709
DOI: 10.1016/j.flowmeasinst.2024.102709
Cited 1 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39111
Preparation and characterization of Mn(II)Mn(III) complexes with relevance to class Ib ribonucleotide reductases
Doyle, L. M.; Bienenmann, R. L. M.; Gericke, R.; Xu, S.; Farquhar, E. R.; Que Jr, L.; McDonald, A. R.
Abstract
The Mn₂ complex (Mn(II)₂(TPDP)(O₂CPh)₂)(BPh₄) (1, TPDP = 1,3-bis(bis(pyridin-2-ylmethyl)amino)propan-2-ol, Ph = phenyl) was prepared and subsequently characterized via single-crystal X-ray diffraction, X-ray absorption, electronic absorption, and infrared spectroscopies, and mass spectrometry. 1 was prepared in order to explore its properties as a structural and functional mimic of class Ib ribonucleotide reductases (RNRs). 1 reacted with superoxide anion (O₂(•–)) to generate a peroxido-MnIIMnIII complex, 2. The electronic absorption and electron paramagnetic resonance (EPR) spectra of 2 were similar to previously published peroxido-Mn(II)Mn(III) species. Furthermore, X-ray near edge absorption structure (XANES) studies indicated the conversion of a Mn(II) 2 core in 1 to a Mn(II)Mn(III) state in 2. Treatment of 2 with para-toluenesulfonic acid (p-TsOH) resulted in the conversion to a new Mn(II)Mn(III) species, 3, rather than causing O—O bond scission, as previously encountered. 3 was characterized using electronic absorption, EPR, and X-ray absorption spectroscopies. Unlike other reported peroxido-Mn(II)Mn(III) species, 3 was capable of oxidative O—H activation, mirroring the generation of tyrosyl radical in class Ib RNRs, however without accessing the Mn(III)Mn(IV) state.
Keywords: Bioinorganic; Dimanganese cluster; Ribonucleotide reductase; Dioxygen activation; electron paramagnetic resonance
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Journal of Inorganic Biochemistry 257(2024), 112583
DOI: 10.1016/j.jinorgbio.2024.112583
Permalink: https://www.hzdr.de/publications/Publ-39110
Spremberg Hyperspectral Drillcore Data
Thiele, S. T.; Kirsch, M.; Madriz Diaz, Y. C.; Gloaguen, R.
Abstract
This hyperspectral drillcore dataset (shed) contains 70 drill holes, totalling 383 boxes that cumulatively contain 1323 meters of scanned cores. Hyperspectral data is stored in the widely used ENVI format (.dat and associated .hdr files), which can be opened using e.g., napari-hippo (GUI) and hylite (python). The whole directory structure is compatible with hycore, for easier out-of-core processing and visualisation.
These hyperspectral data and associated visualisations can also be viewed interactively here.
The scanned cores come from the Spremberg–Graustein Kupferschiefer exploration zone, located in Lusatia, Germany. Five extensive and uninterrupted intervals were scanned, from three boreholes and their deviations drilled by Kupferschiefer Lausitz (KSL) between 2009 and 2010. An additional 65 smaller intervals were also scanned from material drilled during the period spanning 1957 to 1979, a component of the Spremberg exploration initiative executed by the former German Democratic Republic (GDR). Further information on the Spremberg–Graustein exporation zone can be found here.
Stratigraphically, the KSL cores intersect the Rotliegend (Permian) sandstones and conglomerates (S1), the overlying Kupferschiefer mudstone (T1), which transitions upwards into the Zechstein marls, carbonates and evaporites. Data from one hole also includes the base of the Buntsandstein.
The GDR drill cores, housed at the drill core repository of the Geological Survey of Brandenburg (LBGR), predominantly cover a few meters around the immediate intersection of the Kupferschiefer mudstones.
These data were acquired as part of the Horizons Europe project Vector. Kupferschiefer Lausitz and the Geological Survey of Brandenburg are thanked for providing access to core material and their support during data acquisition.
Keywords: mineral deposits; kupferschiefer; sedimentary hosted copper; hyperspectral; resources; germany
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Reseach data in the HZDR data repository RODARE
Publication date: 2024-05-15 Open access
DOI: 10.14278/rodare.2865
Versions: 10.14278/rodare.2866
License: CC-BY-4.0
Downloads
Permalink: https://www.hzdr.de/publications/Publ-39109
Collinstown Hyperspectral Drillcore Data
Thiele, S. T.; Kirsch, M.; Madriz Diaz, Y. C.; Gloaguen, R.
Abstract
This hyperspectral drillcore dataset (shed) contains 10 drill holes, totalling 413 boxes that cumulatively contain 2845 meters of scanned cores. Hyperspectral data is stored in the widely used ENVI format (.dat and associated .hdr files), which can be opened using e.g., napari-hippo (GUI) and hylite (python). The whole directory structure is compatible with hycore, for easier out-of-core processing and visualisation.
These hyperspectral data and associated visualisations can also be viewed interactively here.
These cores intersect stratigraphic units of the Lower Carboniferous Irish Midlands, including the Lucan Formation (Upper Dark Limestones), the Feltrim Formation (Boulder Conglomerate), the Slane Castle Formation (Argillaceous Bioclastic Limestone), the Meath Formation (Shaley Pale Limestones unit), the Liscarton Formation (Mixed Beds unit), and Lower Paleozoic basement rocks.
Scanning was conducted on cores such that a variety of lithology, sedimentary facies, proximity to mineralization, alteration intensity, and dolomitization intensity were sampled.
These data were acquired as part of the Horizons Europe project Vector. Teck Ireland is acknowledged for providing access to core material and assisting with the hyperspectral scanning logistics.
Keywords: mineral deposits; hyperspectral; resources; ireland; sediment hosted Pb-Zn
Related publications
-
Maximising the value of hyperspectral drill core scanning through real-time …
ROBIS: 39121 documents this (Id 39108) publication
-
Reseach data in the HZDR data repository RODARE
Publication date: 2024-05-15 Open access
DOI: 10.14278/rodare.2863
Versions: 10.14278/rodare.2864
License: CC-BY-4.0
Downloads
Permalink: https://www.hzdr.de/publications/Publ-39108
Memory effect in photochromic rare-earth oxyhydride thin films studied by in situ positron annihilation spectroscopy upon photodarkening-bleaching cycling
Wu, Z.; de Wit, L.; Beek, M.; Colombi, G.; Chaykina, D.; Schreuders, H.; Schut, H.; Liedke, M. O.; Butterling, M.; Wagner, A.; Dickmann, M.; Brück, E.; Dam, B.; Eijt, S. W. H.
Abstract
Cycling stability of the photochromic effect in rare-earth oxyhydride thin films is of great importance for longterm applications such as smart windows. However, an increasingly slower bleaching rate upon photochromic cycling was found in yttrium oxyhydride thin films; the origin of this memory effect is yet unclear. In this work, the microstructural changes under six photodarkening-bleaching cycles in YHxOy and GdHxOy thin films are investigated by in situ illumination Doppler broadening positron annihilation spectroscopy, complemented by positron annihilation lifetime spectroscopy (PALS) investigations on YHxOy films before and after one cycle. For the first three cycles, the Doppler broadening S parameter after bleaching increases systematically with photodarkening-bleaching cycle, and correlates with the bleaching time constant extracted from optical transmittance measurements. This suggests that the icrostructural evolution that leads to progressively slower bleaching involves vacancy creation and agglomeration. PALS suggests that during a photodarkening-bleaching cycle, divacancies are formed that are possibly composed of illumination-induced hydrogen vacancies and preexisting yttrium monovacancies, and vacancy clusters grow, which might be due to local removal of hydrogen. If bleaching is a diffusion-related process, the formed vacancy defects induced by illumination might affect the diffusion time by reducing the diffusion coefficient. Hydrogen loss could also be a key factor in the reduced bleaching kinetics. Other microstructural origins including domain growth, or formation of OH−hydroxide groups, are also discussed with respect to the slower bleaching kinetics. During the fourth to sixth photodarkening-bleaching cycle, reversible shifts in the Doppler S and W parameters are seen that are consistent
with the reversible formation of metallic-like domains, previously proposed as a key factor in the mechanism for the photochromic effect.
Keywords: rare-earth oxyhydride; thin films; positron annihilation spectroscopy; smart windows; memory effects; point defects
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- P-ELBE
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 39107) publication
-
Physical Review Materials 8(2024), 045201
DOI: 10.1103/PhysRevMaterials.8.045201
Cited 4 times in Scopus
Downloads
- Secondary publication expected from 15.04.2025
Permalink: https://www.hzdr.de/publications/Publ-39107
Plasma screening in mid-charged ions observed by K-shell line emission
Smid, M.; Humphries, O.; Bähtz, C.; Brambrink, E.; Burian, T.; Cho, M. S.; Gaus, L.; Hájková, V.; Juha, L.; Konopkova, Z.; Le, H. P.; Makita, M.; Pan, X.; Preston, T.; Schropp, A.; Scott, H. A.; Stefanikova, R.; Vorberger, J.; Wang, W.; Zastrau, U.; Falk, K.
Abstract
Dense plasma environment affects the electronic structure of ions via variations of the microscopic
electrical fields, also known as plasma screening. This effect can be either estimated by simplified
analytical models, or by computationally expensive and to date unverified numerical calculations.
We have experimentally quantified plasma screening from the energy shifts of the bound-bound
transitions in matter driven by the x-ray free electron laser (XFEL). This was enabled by identifi-
cation of detailed electronic configurations of the observed Kα, Kβ and Kγ lines. This work paves
the way for improving plasma screening models including connected effects like ionization poten-
tial depression and continuum lowering, which will advance the understanding of atomic physics in
Warm Dense Matter regime.
Involved research facilities
- HIBEF
-
Contribution to WWW
arXiv:2406.06233 [physics.plasm-ph]: https://arxiv.org/abs/2406.06233
DOI: 10.48550/arXiv.2406.06233
Permalink: https://www.hzdr.de/publications/Publ-39106
Neutron Reflectivity for Testing Graphene Oxide Films Sorption of EuCl3 in Ethanol Solution
Nordenström, A.; Boulanger, N.; Vorobiev, A.; Amidani, L.; Bauters, S.; Galanzew, J.; Kvashnina, K.; Talyzin, A.
Abstract
Neutron reflectivity (NR) was used to study the sorption of Eu(III) by graphene oxide (GO) films exposed to ethanol solution of EuCl3. Most of the earlier sorption studies have been performed using GO dispersed in solution. In contrast, layered structure of GO films imposes limitations for penetration of ions between individual sheets. The analysis of NR data recorded before and after sorption under vacuum demonstrates an increase of GO film thickness due to sorption by 35–40%. The characterization of chemical state of Eu(III) sorbed by GO films by X-ray absorption near-edge structure (XANES) in high-energy resolution fluorescence detection (HERFD) method at the Eu L3 edge reveals that it remains the same as in anhydrous EuCl3. Analysis of all collected data including reference experiments with bulk GO samples allows to conclude that EuCl3 penetrates into GO interlayers with ethanol solution and remains trapped in interlayers after evaporation of ethanol. Sorption of EuCl3 results in nearly complete amorphization of film and likely formation of voids, thus making NR models based on specific volume of unit cell not valid for quantitative evaluation of Eu sorption. Limitations of NR method must be taken into account in future studies of sorption by thin films.
Involved research facilities
- Rossendorf Beamline at ESRF DOI: 10.1107/S1600577520014265
Related publications
- DOI: 10.1107/S1600577520014265 is cited by this (Id 39105) publication
-
Physica Status Solidi (B) (2024), 2400069
DOI: 10.1002/pssb.202400069
Permalink: https://www.hzdr.de/publications/Publ-39105
Experimental data for investigating proton bunch monitors for clinical translation of prompt gamma-ray timing
Makarevich, K.; Schellhammer, S.; Pausch, G.; Römer, K.; Tiebel, J.; Turko, J. A. B.; Wagner, A.; Kögler, T.
ResearchGroup: Werner, Rahel-Debora; ResearchGroup: Franke, Anna; ContactPerson: Makarevich, Krystsina; ContactPerson: Kögler, Toni; Project Leader: Kögler, Toni; ResearchGroup: Stach, Daniel; ResearchGroup: Weinberger, David; ResearchGroup: Wolf, Andreas; ResearchGroup: Dreyer, Anne
Abstract
The dataset contains the data reported on https://www.hzdr.de/publications/Publ-39073 where 2 proton bunch monitors (PBMs), namely the diamond detector and the cyclotron monitoring signal Uphi, are established, characterized, and applied for correcting the prompt gamma-ray timing (PGT) data. Experimental setup, irradiation modalities, data acquisition, and data pre- and postprocessing are described there.
The process is summarized in the following:
Experimental setup: A homogeneous cylindrical PMMA phantom was irradiated with a proton beam. Two sets of measurements were considered:
S1) measurements at the horizontal fixed beamline with the control of the beam time structure and current. These data establish the relation between the investigated PBMs and calibrate them to the scattering setup that provides the proton bunch arrival time in the experimental room. The phantom was irradiated with 7 different proton energies Ep = {70, 90, 110, 130, 160, 190, 224} MeV. For each Ep, 3 irradiation modalities were applied:
- CW-mode represented the continuous beam lasting for 30 s, the beam current Ibeam = 2 nA for all Ep excluding 70 MeV (for 70 MeV, Ibeam = 0.5 nA);
- Plan I represented a clinically realistic plan with a spot duration of 4 ms and a spot repetition time of 7 ms. The beam current Ibeam = 1 nA for all Ep excluding 70 MeV (for 70 MeV, Ibeam = 0.5 nA);
- Plan II aimed to reproduce the measurements of Werner et al. (2019) in Phys. Med. Biol. 64 105023, 20pp (https://doi.org/10.1088/1361-6560/ab176d). For that, the spot duration was set to 69 ms, and the repetition time was 72 ms. The beam current Ibeam = 1 nA for all Ep excluding 70 MeV (for 70 MeV, Ibeam = 0.5 nA).
S2) measurements at the pencil beam scanning (PBS) beamline were similar to those at the clinical beam delivery nozzle. The PBS beamline delivers the beam as spots of given intensity (expressed in MU), (x,y)-coordinates, and energy (corresponds to the penetration depth or z-coordinate). These data comprise data from the PGT detector and PBMs and are used to correct the PGT data employing the investigated PBMs. The phantom was irradiated with 8 different proton energies Ep = {70, 90, 110, 130, 162, 180, 200, 220} MeV. For every energy, 2 spot intensities were considered: 0.1 MU per 1 spot (~1e7 protons) and 1 MU per 1 spot (~1e8 protons). For Ep = 162 MeV, an additional spot intensity of 10 MU per 1 spot (~1e9 protons) was applied to reproduce the measurements of Werner et al. (2019) in Phys. Med. Biol. 64 105023, 20pp (https://doi.org/10.1088/1361-6560/ab176d).
Data preprocessing:
The raw data of each measurement were converted from the binary list-mode format to ROOT TTrees. The data were corrected for the photomultiplier gain drift, and digitalization time non-linearities, and the integral signal was converted into deposited energy. For the measurements at the fixed beamline, the coincidence analysis was applied additionally for non-PBM detectors. The data were assigned to individual corresponding spots for the PBS beamline measurements.
Data structure:
The ROOT files are named u100-p00XX-yyyy-mm-dd_HH.MM.SS+TZ.root where p00XX is the detector’s number, yyyy-mm-dd_HH.MM.SS is the time of the measurement, and TZ is the time zone. Here, p0012 and p0019 mean scintillating detectors that were used both at the fixed beamline, and only detector p0012 was used for PGT measurements at the PBS beamline. P0015 is the diamond detector, and p0017 contains data of the Uphi signal.
In general, the data structure inside the ROOT files is different depending on the purpose of the detector. However, there are some general includes:
- data (TTree) contains list-mode data which comprises
- uncorrected data: before corrections and calibrations steps;
- corrected data: after correcations and calibrations steps;
- meta (TTree) is a measurement metadata (applied detector voltage, the start time of the measurements, etc.);
- histograms is a directory with selected example histograms (uncorrected);
- analysis is a directory with histograms with corrected data used for the analysis.
For further questions, please refer to the contact persons stated above.
Keywords: prompt gamma timing; PGT; proton bunch monitor; PBM; proton range verification
Involved research facilities
- OncoRay
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Reseach data in the HZDR data repository RODARE
Publication date: 2024-05-16 Open access
DOI: 10.14278/rodare.2871
Versions: 10.14278/rodare.2872
License: CC-BY-4.0
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Permalink: https://www.hzdr.de/publications/Publ-39104
Raw data and data used for figures in "Visualizing Plasmons and Ultrafast Kinetic Instabilities in Laser-Driven Solids using X-ray Scattering"
Abstract
Data and visualization scripts for "Visualizing Ultrafast Kinetic Instabilities in Laser-Driven Solids using X-ray Scattering"
Involved research facilities
- HIBEF
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Visualizing Ultrafast Kinetic Instabilities in Laser-Driven Solids using X-ray …
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Visualizing plasmons and ultrafast kinetic instabilities in laser-driven …
ROBIS: 39534 has used this (Id 39103) publication of HZDR-primary research data
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Reseach data in the HZDR data repository RODARE
Publication date: 2023-03-16 Open access
DOI: 10.14278/rodare.2183
Versions: 10.14278/rodare.2184
License: CC-BY-4.0
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Permalink: https://www.hzdr.de/publications/Publ-39103
Stonepark Hyperspectral Drillcore Data
Thiele, S. T.; Kirsch, M.; Madriz Diaz, Y. C.; Gloaguen, R.; El Alami, S.; Cecilia Contreras Acosta, I.; Saffi, H.
Abstract
This hyperspectral drillcore dataset (shed) contains 14 drill holes, totalling 389 boxes that cumulatively contain 2513 meters of scanned cores. Hyperspectral data is stored in the widely used ENVI format (.dat and associated .hdr files), which can be opened using e.g., napari-hippo (GUI) and hylite (python). The whole directory structure is compatible with hycore, for easier out-of-core processing and visualisation.
These hyperspectral data and associated visualisations can also be viewed interactively here.
The scanned drillcores were selected to cover the main mineralised intervals and key stratigraphic horizons, sedimentary facies, igneous intrusions, brecciation and alteration zones present at Stonepark. These include the Knockroe Fm and Knockseefin Fm, the Lough Gur Formation, the Waulsortian Limestone Formation, and the Ballysteen Formation (Argillaceous Bioclastic Limestone). Drillcore selection was further based on the availability and accessibility of drill core and sought to capture the variations both laterally and vertically, in consultation with geologists from Group Eleven Resources.
These data were acquired as part of the Horizons Europe project Vector. We would also like to acknowledge Group Eleven, for providing access to core material and their support during data acquisition.
Keywords: mineral deposits; hyperspectral; resources; ireland; sediment hosted Pb-Zn
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ROBIS: 39121 documents this (Id 39102) publication -
Maximising the value of hyperspectral drill core scanning through real-time …
ROBIS: 39121 has used this (Id 39102) publication of HZDR-primary research data
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Reseach data in the HZDR data repository RODARE
Publication date: 2024-05-15 Open access
DOI: 10.14278/rodare.2867
Versions: 10.14278/rodare.2868
License: CC-BY-4.0
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Permalink: https://www.hzdr.de/publications/Publ-39102
Werkzeuge und Methoden zur verbesserten fluiddynamischen Auslegung von Querstromböden mit Hochleistungsventilen
Abstract
Übersichtsvortrag zum IGF-Vorhaben 20835 BG: 1) Motivation, 2) Übersicht zur Projektstruktur, Arbeitsschwerpunkten und beteiligten Forschungseinrichtungen, 3) Darstellung ausgewählter Ergebnisse: a) DN1200-Versuchskolonne mit Strömungsfeldsensor, b) Simulation der Bodenüberströmung, 4) Zusammenfassung und Ausblick auf fortführende Forschungsarbeiten sowie zum Transfer der Ergebnisse in die Wirtschaft
Keywords: Destillation; Kolonnenboden; Querstromboden; GVT; GVT Projekt des Jahres 2024
-
Invited lecture (Conferences)
Vortragsveranstaltung des GVT-Forschungsbeirats im Rahmen der GVT-Jahreshauptversammlung, 06.-07.05.2024, Leverkusen, Deutschland
Permalink: https://www.hzdr.de/publications/Publ-39101
Combinatorial targeting of Glioblastoma using the Switchable Dual-RevCAR T Cell System
Abdelfatah Saleh Hassan, H. A.; Mitwasi, N.; Arndt, C.; Rodrigues Loureiro, L. R.; Kegler, A.; Kubeil, M.; Toussaint, M.; Deuther-Conrad, W.; Bachmann, M.; Feldmann, A.
Abstract
Glioblastoma (GBM) remains a challenge in oncology, characterized by poor prognosis despite existing treatments. Therefore, novel therapeutic strategies are urgently needed. Immunotherapies, particularly chimeric antigen receptor (CAR) T cells, that have shown impressive clinical results in hematological malignancies, might also offer a promising avenue for GBM. However, effectively targeting GBM with conventional CAR therapies is limited due to tumor microenvironment, tumor heterogeneity, tumor escape by antigen loss, and potential off-target effects. To address these limitations, we have employed our adaptable RevCAR system to target both the epidermal growth factor receptor (EGFR) and the disialoganglioside (GD2), which are overexpressed on GBM cells. The RevCAR system presents a switchable platform offering control, enhanced safety, and specificity. Essentially, it comprises RevCAR T cells equipped with a peptide epitope as the extracellular domain and a bispecific target module (RevTM). The RevTM cross-links the RevCAR epitope and the tumor-specific antigen, thereby activating RevCAR T cells to eliminate tumor cells. Furthermore, the RevTM functions as a molecular switch, as in the absence of the RevTM, RevCAR T cells remain inactive. In this study, we demonstrate that the novel EGFR- or GD2-specific RevTMs can selectively bind to EGFR or GD2 on tumor cells and activate RevCAR T cells to eradicate GBM cells. Furthermore, we exhibit the feasibility of targeting GBM with our Dual-RevCAR T cells, wherein the first activation (derived from CD3) and co-stimulatory (derived from CD28) signaling domains are separated onto two receptors. Consequently, complete activation of Dual-RevCAR T cells requires simultaneous recognition of EGFR and GD2 by both receptors via RevTMs, resulting in precise GBM cell killing both in vitro and in vivo. In conclusion, the switchable RevCAR platform is a novel therapeutic approach that provides improved safety and allows combinatorial targeting of GBM.
Involved research facilities
- PET-Center
-
Poster
Recent insights in Onco-Immunology, 30.-31.05.2024, Antwerp, Belgium
Permalink: https://www.hzdr.de/publications/Publ-39100
High-count rate photon detection with scintillators coupled to photomultiplier tubes and fast digitizers
García Rivas, I.; Fernández Prieto, A.; Kögler, T.; Römer, K.; Hueso González, F.
Abstract
This repository contains raw experimental data acquired during the gELBE beam time performed in October 2023 under proposal number 23203137-ST, at Helmholtz-Zentrum Dresden - Rossendorf.
In this setup, a bremsstrahlung beam of up to 12.5 MeV energy in 13 MHz pulses irradiates a CeBr3 scintillation detector (by Hilger®) of Ø 1'' x 1'', coupled to a Hamamatsu® R13408-100 PMT, custom voltage divider and shaping electronics, and a commercial digitizer (SFMC01+SIS1160) by Struck®, containing an AD9689 chip that supports a data sampling rate of 2.5 Gsps and 14-bits. This detector is developed in the context of the coaxial prompt gamma-ray monitoring method [1], where very high count rates are expected [2]. The dead-time-free data acquisition is programmed in-house using ROOT [3]. In addition, a plastic scintillation detector (paddle) was placed inbetween the beam and the CeBr3 crystal to serve as reference beam monitor. An Arduino is used to monitor the high-voltage supply for the PMT and active divider electronics in terms of current, voltage and temperature. A Comet Systems® T7310 is used to monitor ambient temperature, humidity and pressure.
The published data consist of the raw signal waveforms acquired during ~450 measurements. Each measurement is stored in a separate folder, its name being the acquisition time start, and lasts between 3 and 20 seconds (16 GiB up to 100 GiB). The data format is little-endian binary. Each sample uses two bytes, being the 14 first bits the digitized signal in a 1.7 Vpp range, and the 15th bit the (negated) logic status of the reference beam monitor (paddle). Samples are stored consecutively, without headers. Sample time separation is 0.4 ns (2.5 Gsps). The digitizer is phase-locked to the accelerator radiofrequency (RF), so that each 2500 stored samples correspond to 13 consecutive periods of 13 MHz.
The data can be directly opened using the open-source pulse visualization software (PulseSurfer) available in this link: https://igit.ific.uv.es/ferhue/pulse-surfer/, with ROOT as a dependency. One just needs to run:
root -l test_gui.cpp+(\"/path-to-folder/chA.bin\")
and then set 192.307692307692307696 in the "Cycle" box. Use the slider in the bottom to navigate across different consecutive frames. To visualize the paddle counter (negated) logic status, change the "Mask" box from 3FFF to 4000. There is also a checkbox to activate the baseline subtraction.
In addition to the raw waveform data (chA.bin), each folder contains following metadata:
- log.root a ROOT file storing all the measurement and hardware settings as TObjString. It also contains the T7310 monitoring as a TTree ("pth")
- chA.root a ROOT file storing a TTree that benchmarks the readout speed of the DAQ for this channel
- zdt.log a text file storing the output printed by the DAQ software to terminal
- gui.png Screenshot of the DAQ window
- hv.txt a test file storing the monitoring of the high-voltage supply and electronics
Keywords: Proton Therapy; Range Verification; High-count rate photon detection; high speed digitizers; pile-up deconvolution
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- γ-ELBE DOI: 10.58065/24020
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Reseach data in the HZDR data repository RODARE
Publication date: 2024-04-16 Open access
DOI: 10.14278/rodare.2806
Versions: 10.14278/rodare.2807
License: CC-BY-4.0
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Permalink: https://www.hzdr.de/publications/Publ-39098
Si1-x-yGeySnx alloy formation by Sn ion implantation and flash lamp annealing
Steuer, O.; Michailow, M.; Hübner, R.; Pyszniak, K.; Turek, M.; Kentsch, U.; Ganss, F.; Khan, M. M.; Rebohle, L.; Zhou, S.; Knoch, J.; Helm, M.; Cuniberti, G.; Georgiev, Y.; Prucnal, S.
Abstract
For many years, Si1-yGey alloys have been applied in the semiconductor industry due to the ability to adjust the performance of Si-based nanoelectronic devices. Following this alloying approach of group-IV semiconductors, adding tin into the alloy appears as the obvious next step, which leads to additional possibilities for tailoring the material properties. Adding Sn enables effective band gap and strain engineering and can improve the carrier mobilities, which makes Si1-x-yGeySnx alloys promising candidates for future opto- and nanoelectronics applications. The bottom-up approach for epitaxial growth of Si1-x-yGeySnx, e.g., by chemical vapor deposition and molecular beam epitaxy, allows tuning the material properties in the growth direction only; the realization of local material modifications to generate lateral heterostructures with a such a bottom up approach is extremely elaborate since it would require the use of lithography, etching and either selective epitaxy or epitaxy and chemical-mechanical polishing giving rise to interface issues, non-planar substrates etc. This article shows the possibility of fabricating Si1-x-yGeySnx alloys by Sn implantation into Si1-yGey layers followed by millisecond-range flash lamp annealing. The materials are investigated by Rutherford backscattering spectrometry, micro Raman spectroscopy, X-ray diffraction, and transmission electron microscopy. The fabrication approach was adapted to ultra-thin Si1-yGey layers on silicon-on-insulator substrates. Finally, we show the possibility of implanting Sn locally in ultra-thin Si1-yGey films. We demonstrate the realization of vertical AND lateral Si1-x-yGeySnx heterostructures by tin ion implantation and flash lamp annealing.
Keywords: Implantation; SiGeSn; Si1-x-yGeySnx; Sn; FLA; Flash lamp annealing
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
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- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 39097) publication
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Si1-x-yGeySnx alloy formation by Sn ion implantation and flash lamp annealing
ROBIS: 39199 HZDR-primary research data are used by this (Id 39097) publication
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Journal of Applied Physics 136(2024)6, 065701
DOI: 10.1063/5.0220639 -
Poster
EMRS Fall Meeting 2024, 16.-19.09.2024, Warsaw, Poland
Permalink: https://www.hzdr.de/publications/Publ-39097
Software engineering for validating finite-temperature XC-functional
Lokamani, M.; Ramakrishna, K.; Hüser, C.; Huste, T.; Cangi, A.; Juckeland, G.
Abstract
In recent years, density functional theory (DFT) has revolutionzed simulations in the domain of warm dense matter (WDM) which focuses on unraveling behavior of matter in fusion reactor, planetary interiors and other areas of high energy physics. The success of DFT relies on accurate approximations of the exchange-correlation (XC) effects based on exact quantum monte carlo (QMC) results. In this contribution, we summarize our recent work toward improving XC at finite temperatures, which is called thermal PBE[1] and incorporting the improvements in LIBXC[2], a library widely used in the material science community. We highlight the software engineering challenges in the field of high performance computing including: (i) deployment of continuous integration (CI) using Gitlab runners, (ii) incorporating containers for CI and reproducibility and (iii) refactoring strategies. We also highlight the importance of research software engineering (RSE) for validating accurate utilization of community high-performance-computing codes.
References
[1] https://doi.org/10.48550/arXiv.2308.03319
[2] https://doi.org/10.1016/j.softx.2017.11.002
Keywords: density functional theory; EVERSE; thermalPBE; research software engineering
-
Lecture (Conference)
RSEHPC@ISC24, 12.-16.05.2024, Hamburg, Germany
Downloads
Permalink: https://www.hzdr.de/publications/Publ-39096
Adaptive intensity modulated proton therapy using 4D robust planning: a proof-of-concept for the application of dose mimicking approach
Kaushik, S.; Stützer, K.; Ödén, J.; Fredriksson, A.; Toma-Dasu, I.
Abstract
Objective: A 4D robust optimisation (4DRO) is usually employed when addressing respiratory motion for tumour is important. However, it is computationally demanding, and an automated method is preferable for adaptive planning to avoid manual trial-and-error. This study proposed a 4DRO technique based on dose mimicking for adaptive planning.
Approach: The initial plans for 4D robust IMPT were created on an average CT (avgCT) of each of the four patients with clinical target volume (CTV) in the lung, oesophagus, or pancreas. These plans were robustly optimized using three phases of 4DCT and accounting for setup and density uncertainties. Weekly 4DCTs were used for adaptive replanning, using a constant relative biological effectiveness (cRBE) of 1.1. Two methods were used for this purpose: (1)
template-based adaptive (TA) plan and (2) dose-mimicking-based adaptive (MA) plan. Furthermore, variable RBE (vRBE) weighted doses and biologically consistent dose accumulation was performed for evaluation.
Main results: Both TA and MA plans had comparable CTV coverage expect one patient where the MA plan had a higher D98 and lower D2 but with an increased D2 in an OAR. Individual NA plans showed a decrease in CTV D98 of up to −7.2%, however, it was recovered for all cases with dose accumulation. For all OARs, the MA plans consistently showed a reduced mean dose and D2 in the OAR compared to the TA plan, with some exceptions. The vRBE-weighted accumulated dose had a mean dose and D2 difference of up to 0.3 Gy and 0.5 Gy, respectively, in the OARs with respect to cRBE-weighted dose.
Significance: The MA plans indicates better performance in target coverage and OAR dose sparing compared to the TA plans. This method is capable of handling both forms of anatomical variation, namely changes in density and relative shifts in the position of the OARs.
-
Physics in Medicine and Biology 69(2024)18, 185010
DOI: 10.1088/1361-6560/ad75e0
Permalink: https://www.hzdr.de/publications/Publ-39093
Structure and Standard Entropy of Ba2MoO5
van Hattem, A.; de Geus, L.; Sacristan, A.; Dankelman, R.; Couweleers, S.; Hennig, C.; Colineau, E.; Griveau, J.-C.; Dardenne, K.; Rothe, J.; Konings, R. J. M.; Smith, A. L.
Abstract
The detailed crystal structure as well as the heat capacity at low temperature and standard entropy of Ba2MoO5 are reported for the
first time. High-resolution X-ray and neutron diffraction were employed to reveal the structural features of Ba2MoO5. Ba2MoO5
has a six-coordinated Mo and an exceptionally strongly negative excess volume. X-ray Absorption Near Edge Structure (XANES)
spectroscopy at the Mo K-edge shows Mo to be in the oxidation state 6+. The pre-edge peak in the XANES spectrum indicates
a distorted octahedral environment, in line with the results from diffraction studies. The standard entropy and heat capacity of
Ba2MoO5 at 298.15 K, determined with a thermal-relaxation technique, are calculated to be respectively 223.2±7 and 184.7±5
J·K−1· mol−1. The obtained thermodynamic properties are discussed with reference to literature on molybdate compounds.
Keywords: Ba-Mo-O; calorimetry; heat capacity; Ba2MoO5; Neutron Diffraction; XRD; XANES
Involved research facilities
- Rossendorf Beamline at ESRF DOI: 10.1107/S1600577520014265
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Inorganic Chemistry 64(2025), 674-681
DOI: 10.1021/acs.inorgchem.4c03617
Permalink: https://www.hzdr.de/publications/Publ-39092
A Supervised Approach for Estimating Fractional Abundances of Binary Intimate Mixtures
Koirala, B.; Rasti, B.; Scheunders, P.
Abstract
In this work, we propose a supervised framework for spectral unmixing of binary intimate mixtures. The core idea is based on geodesic distance measurements and regression to estimate the fractional abundances. The main assumption is that spectral reflectances of binary mixtures form a curve between the two endmembers, and the mixture's relative position on this curve serves as an indicator of its fractional abundances. We propose four novel approaches to approximate this relative position. From this, the fractional abundances are obtained using Gaussian process regression. The proposed framework simultaneously copes with the spectral variability by hypersphere and high-dimensional simplex projections. The approach is extensively validated on real datasets, including binary mineral mixtures and industrial clay powder mixtures produced in a laboratory setting, comprising 60 binary mixtures derived from five types of clay powders: Kaolin, Roof clay, Red clay, mixed clay, and Calcium hydroxide, measured by a variety of hyperspectral sensors in the VNIR-SWIR and mid-and longwave infrared regions. A comparison with the linear mixing model and several nonlinear mixing models demonstrates the superiority of the proposed approach.
Keywords: Earth; Estimation; Hyperspectral; Hyperspectral imaging; Mathematical models; mineral powder mixture
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IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing 17(2024), 8956-8966
DOI: 10.1109/JSTARS.2024.3387750
Permalink: https://www.hzdr.de/publications/Publ-39090
Quantum critical fluctuations in a transverse-field Ising magnet
Hauspurg, A.; Matsuura, K.; Arima, T.; Zherlitsyn, S.; Wosnitza, J.
Abstract
CoNb2O6 is a model system for a spin-1/2 one-dimensional (1D) transverse-field Ising magnet (TFIM) with a rather low three-dimensional (3D) Néel ordering temperature at TN = 2.95 K. We studied CoNb2O6 using ultrasound measurements down to 0.3 K in transverse magnetic fields applied along the b direction. Upon entering the 3D ordered state, we observe pronounced anomalies in the transverse acoustic mode c66. In particular, from 1.3 to 1.5 K and around 4.7 T, this mode reveals an almost diverging softening, which is considerably reduced at lower and higher magnetic fields. We interpret this as an influence of quantum critical fluctuations emerging from the quantum critical point (QCP) of the 1D Ising spin chains at about 4.75 T, which lies below the QCP of the 3D ordering at about 5.4 T. This is clear experimental evidence of the predicted generic phase diagram for a TFIM with superimposed 3D ordering.
Involved research facilities
- High Magnetic Field Laboratory (HLD)
-
Journal of Physics: Condensed Matter 36(2024), 325801
DOI: 10.1088/1361-648X/ad44fc
Permalink: https://www.hzdr.de/publications/Publ-39089
Fractionalized excitations probed by ultrasound
Hauspurg, A.; Zherlitsyn, S.; Helm, T.; Felea, V.; Wosnitza, J.; Tsurkan, V.; Choi, K.-Y.; Do, S.-H.; Ye, M.; Brenig, W.; Perkins, N. B.
Abstract
In this work, we study magnetoelastic interactions by means of ultrasound experiments in α-RuCl3—a prototypical material for the Kitaev spin model on the honeycomb lattice, with a possible spin-liquid state featuring Majorana fermions and Z2-flux excitations. We present results of the temperature and in-plane magnetic-field dependence of the sound velocity and sound attenuation for several longitudinal and transverse phonon modes propagating along high-symmetry crystallographic directions. A comprehensive data analysis above the magnetically ordered state provides strong evidence of phonon scattering by Majorana fermions. This scattering depends sensitively on the value of the phonon velocities relative to the characteristic velocity of the low-energy fermionic excitations describing the spin dynamics of the underlying Kitaev magnet. Moreover, our data displays a distinct reduction of anisotropy of the sound attenuation, consistent with the presence of thermally excited Z2 visons. We demonstrate the potential of phonon dynamics as a promising probe for uncovering fractionalized excitations in α-RuCl3 and provide new insights into the H-T phase diagram of this material.
Involved research facilities
- High Magnetic Field Laboratory (HLD)
-
Physical Review B 109(2024), 144415
DOI: 10.1103/PhysRevB.109.144415
arXiv: arXiv:2303.09288
Cited 4 times in Scopus
Downloads
- Open Access Version from arxiv.org
- Secondary publication expected from 18.04.2025
Permalink: https://www.hzdr.de/publications/Publ-39088
Narrowly avoided spin-nematic phase in BaCdVO(PO4)2: NMR evidence
Ranjith, K. M.; Povarov, K.; Yan, Z.; Zheludev, A.; Horvatic, M.
Abstract
We present a 31P NMR investigation of BaCdVO(PO4)2 focusing on the nearly saturated regime between μ0Hc1 = 4.05 T and μ0Hc2 = 6.5 T, which used to be considered a promising candidate for a spin-nematic phase. NMR spectra establish the absence of any dipolar order there, whereas the weak field dependence of the magnetization above Hc1 is accounted for by Dzyaloshinskii-Moriya interaction terms. The low-energy spin dynamics (fluctuations), measured by the nuclear spin-lattice relaxation rate T1
−1, confirms the continuity of this phase and the absence of any low-temperature phase transition. Unexpectedly, the spin dynamics above Hc1 is largely dominated by two-magnon processes, which is expected above the saturation field of a spin-nematic phase, but not inside. This shows that BaCdVO(PO4)2 is indeed close to a spin-nematic instability; however, this phase is not stabilized. We thus confirm recent theoretical predictions that the spin-nematic phase can be stabilized, at most, in an extremely narrow field range close to saturation or is rather narrowly avoided [Jiang et al., Phys. Rev. Lett. 130, 116701 (2023)].
Involved research facilities
- High Magnetic Field Laboratory (HLD)
-
Physical Review Research 6(2024), 023043
DOI: 10.1103/PhysRevResearch.6.023043
Permalink: https://www.hzdr.de/publications/Publ-39087
Dynamic exchange correlation effects in the strongly coupled electron liquid
Dornheim, T.; Tolias, P.; Kalkavouras, F.; Moldabekov, Z.; Vorberger, J.
Abstract
We present the first quasi-exact \textit{ab initio} path integral Monte Carlo (PIMC) results for the dynamic local field correction $\widetilde{G}(\mathbf{q},z_l;r_s,\Theta)$ in the imaginary Matsubara frequency domain, focusing on the strongly coupled finite temperature uniform electron gas. These allow us to investigate the impact of dynamic exchange--correlation effects onto the static structure factor. Our results provide a straightforward explanation for previously reported spurious effects in the so-called \textit{static approximation} [Dornheim \textit{et al.}, \textit{Phys.~Rev.~Lett.}~\textbf{125}, 235001 (2020)], where the frequency-dependence of the local field correction is neglected. Our findings hint at the intriguing possibility of constructing an analytical four-parameter representation of $\widetilde{G}(\mathbf{q},z_l;r_s,\Theta)$ valid for a substantial part of the phase diagram, which would constitute key input for thermal density functional theory simulations.
Related publications
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Data publication: Dynamic exchange–correlation effects in the strongly coupled …
ROBIS: 39422 HZDR-primary research data are used by this (Id 39086) publication
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Physical Review B 110(2024)7, 075137
DOI: 10.1103/PhysRevB.110.075137
Cited 1 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39086
Associations of life-course cardiovascular risk factors with late-life cerebral haemodynamics
Dijsselhof, M. B. J.; Holtrop, J.; James, S.-N.; Lu, K.; Lorenzini, L.; Collij, L. E.; Scott, C. J.; Manning, E. N.; Insight, 4. S. T.; Thomas, D. L.; Richards, M.; Hughes, A. D.; Cash, D. M.; Barkhof, F.; Schott, J. M.; Petr, J.; Mutsaerts, H. J. M. M.
Abstract
While the association of mid-life cardiovascular risk factors with late-life white matter lesions (WMH) and cognitive decline have been established, the role of cerebral haemodynamics is unclear. We investigated the relation of late-life (69-71 years) arterial spin labelling (ASL) MRI-derived cerebral blood flow (CBF) with life-course cardiovascular risk factors (36-71 years) and late-life white matter hyperintensity (WMH) load in 282 cognitively healthy participants (52.8% female). Late-life (69-71 years) high systolic (β = -0.15) and diastolic (β = -0.25) blood pressure, and mean arterial pressure (β = -0.25) were associated with low GM CBF (p < 0.03), and WM CBF (β = -0.25; β = -0.15; β = -0.13, p < 0.03, respectively). The association between systolic blood pressure and GM CBF differed between sexes (male/female β = -0.15/0.02, p = 0.04). No associations were found with early- or mid-life cardiovascular risk factors. All cerebral haemodynamic parameters were associated with WMH volume. These findings suggest that cerebral autoregulation is able to maintain stable global cerebral haemodynamics until later in life. Future studies are encouraged to investigate why cardiovascular risk factors have differential effects on haemodynamics and WMH, and their implications for cognitive decline.
Involved research facilities
- PET-Center
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Journal of Cerebral Blood Flow and Metabolism (2025)
Online First (2024) DOI: 10.1177/0271678X241301261
Permalink: https://www.hzdr.de/publications/Publ-39085
Kinetically controlled metal-elastomer nanophases for environmentally resilient stretchable electronics
Chae, S.; Jin Choi, W.; Julia Nebel, L.; Hee Cho, C.; Besford, Q. A.; Knapp, A.; Makushko, P.; Zabila, Y.; Pylypovskyi, O.; Woo Jeong, M.; Avdoshenko, S.; Sander, O.; Makarov, D.; Jang Chung, Y.; Fery, A.; Young Oh, J.; Il Lee, T.
Abstract
Nanophase mixtures, leveraging the complementary strengths of each component, are vital for composites to overcome limitations posed by single elemental materials. Among these, metal-elastomer nanophases are particularly important, holding various practical applications for stretchable electronics. However, the methodology and understanding of nanophase mixing metals and elastomers are limited due to difficulties in blending caused by thermodynamic incompatibility. Here, we present a controlled method using kinetics to mix metal atoms with elastomeric chains on the nanoscale. We find that the chain migration flux and metal deposition rate are key factors, allowing the formation of reticular nanophases when kinetically in-phase. Moreover, we observe spontaneous structural evolution, resulting in gyrified structures akin to the human brain. The hybridized gyrified reticular nanophases exhibit strain-invariant metallic electrical conductivity up to 156% areal strain, unparalleled durability in organic solvents and aqueous environments with pH 2–13, and high mechanical robustness, a prerequisite for environmentally resilient devices.
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Nature Communications 15(2024), 3071
DOI: 10.1038/s41467-024-47223-6
Cited 5 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39084
Dual time-point [18F]FDG PET imaging for quantification of metabolic uptake rate: Evaluation of a simple, clinically feasible method
Samimi, R.; Kamali-Asl, A.; Ahmadyar, Y.; van den Hoff, J.; Geramifar, P.; Rahmim, A.
Abstract
Purpose: We aimed to investigate whether a clinically feasible dual time-point (DTP) approach can accurately estimate the metabolic uptake rate constant (Ki) and to explore reliable acquisition times through simulations and clinical assessment considering patient comfort and quantification accuracy. Methods: We simulated uptake kinetics in different tumors for four sets of DTP PET images within the routine clinical static acquisition at 60-min post-injection (p.i.). We determined Ki for a total of 81 lesions. Ki quantification from full dynamic PET data (Patlak-Ki) and Ki from DTP (DTP-Ki) were compared. In addition, we scaled a population-based input function (PBIFscl) with the image-derived blood pool activity sampled at different time points to assess the best scaling time-point for Ki quantifications in the simulation data. Results: In the simulation study, Ki estimated using DTP via (30,60–min), (30,90–min), (60,90-min), and (60,120-min) samples showed strong correlations (r ≥ 0.944, P < 0.0001) with the true value of Ki. The DTP results with the PBIFscl at 60-min time-point in (30,60–min), (60,90-min), and (60,120-min) were linearly related to the true Ki with a slope of 1.037, 1.008, 1.013 and intercept of −6 × 10−4, 2 × 10−5, 5 × 10−5, respectively. In a clinical study, strong correlations (r ≥ 0.833, P < 0.0001) were observed between Patlak-Ki and DTP-Ki. The Patlak-derived mean values of Ki, tumor-to-background-ratio, signal-to-noise-ratio, and contrast-to-noise-ratio were linearly correlated with the DTP method. Conclusions: Besides calculating the retention index as a commonly used quantification parameter in DTP imaging, our DTP method can accurately estimate Ki. © 2024 Associazione Italiana di Fisica Medica e Sanitaria
Keywords: Dynamic PET; Patlak analysis; [18F]FDG quantification
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Physica Medica, European Journal of Medical Physics 121(2024), 103336
DOI: 10.1016/j.ejmp.2024.103336
Permalink: https://www.hzdr.de/publications/Publ-39083
Data publication: Defect Microstructure Evolution in Immiscible Composite Cu43%Cr Alloy after High-Pressure Torsion and Annealing using Positron Annihilation Spectroscopy
Bibimoune, I.; Hirschmann, E.; Liedke, M. O.; Wagner, A.; Kawasaki, M.; Baudin, T.; Mkinsi, I.; Abib, K.; Huang, Y.; Langdon, T. G.; Bradai, D.
Abstract
This data set contains positron annihilation lifetime spectra and VEPAS-DB spectra. It contains raw data and the corresponding analyzed data.
Keywords: Cu-Cr; immiscible alloys; high-pressure torsion; defects; positron annihilation spectroscopy
Related publications
- DOI: 10.1007/s12540-024-01745-2 references this (Id 39080) publication
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Defect Microstructure Evolution in Immiscible Composite Cu43%Cr Alloy after …
ROBIS: 39078 has used this (Id 39080) publication of HZDR-primary research data
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Reseach data in the HZDR data repository RODARE
Publication date: 2024-05-13 Closed access
DOI: 10.14278/rodare.2859
Versions: 10.14278/rodare.2860
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Permalink: https://www.hzdr.de/publications/Publ-39080
P2M systems based on proton-conducting solid oxide cells: Future prospects and costs of renewable methanol production
Fogel, S.; Unger, S.; Hampel, U.
Abstract
Methanol is considered as an essential base chemical, which is widely known for its versatility and broad potential use contexts in future chemical industries and energy storage applications. Methanol production pathways powered by renewable electricity sources, also known as power-to-methanol processes, are characterized by low specific life-cycle emissions and are therefore of paramount interest. One possible renewable process chain features proton-conducting high temperature electrolyzers combined with a direct hydrogenation of CO2. In this paper, a techno-economic forecast study of this process chain is presented and specific production costs of renewable methanol under different electricity supply scenarios are determined and discussed for the years 2030 and 2050. The studies showed that flexible grid-supported scenarios through direct spot-market participation and renewable scenarios enable the largest production cost reduction potential in the upcoming decades.
Keywords: Power-to-Liquid; SOEC; Techno-Economic Assessment; Methanol; Cost Projection
Involved research facilities
- TOPFLOW Facility
- ROFEX
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Energy Conversion and Management: X 23(2024), 100666
DOI: 10.1016/j.ecmx.2024.100666
Cited 1 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39079
Defect Microstructure Evolution in Immiscible Composite Cu43%Cr Alloy after High-Pressure Torsion and Annealing using Positron Annihilation Spectroscopy
Bibimoune, I.; Hirschmann, E.; Liedke, M. O.; Wagner, A.; Kawasaki, M.; Baudin, T.; Mkinsi, I.; Abib, K.; Huang, Y.; Langdon, T. G.; Bradai, D.
Abstract
The microstructure of a Cu43%Cr alloy after high-pressure torsion (HPT) processing and annealing for 1 hour was analyzed using Doppler broadening – variable energy PAS (DB-VEPAS) and conventional positron annihilation lifetime spectroscopy (cPALS). DB-VEPAS analysis of the near-surface defects reveals the existence of a nanosized oxide layer, whose thickness increases from 43 nm to 103 nm with temperature (210°C-850 °C), while the diffusion length is unaffected around 20 nm. cPALS analysis evidenced two lifetime components of the bulk defects, namely the components related to either vacancy or dislocation, for the as-received material with annealing at 925°C. After HPT processing, the alloy showed two components which correspond to positrons trapped and annihilated at dislocations (lifetime ̴ 160 ps) in Cu and Cr and at clusters of vacancies (about 13-10 vacancies). The intensity of the first component decreases with increasing annealing temperatures from 210 to 850 °C, thereby implying a partial annihilation of dislocations due to the microstructure recovery. The variation of the second component depends on the variation of vacancy cluster size (from about 13 and 10 to about 4 vacancies) resulting from different annealing temperatures. Additionally, the Vickers microhardness measurements show that the alloy is substantially hardened after processing by HPT for N = 20 turns. After annealing for 1 hour at 210, 550, and 850°C, the HPT-processed alloy after 5 turns demonstrated a gradual softening by the microstructural recovery. Annealing-induced hardening is observed after HPT for 20 turns followed by heating up to 550°C, while softening is observed after annealing at 850°C.
Keywords: Cu-Cr; immiscible alloys; high-pressure torsion; defects; positron annihilation spectroscopy
Related publications
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Data publication: Defect Microstructure Evolution in Immiscible Composite …
ROBIS: 39080 HZDR-primary research data are used by this (Id 39078) publication
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Metals and Materials International (2025)
Online First (2024) DOI: 10.1007/s12540-024-01745-2
Cited 1 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39078
Multimessenger measurements of the static structure of shock-compressed liquid silicon at 100 GPa
Poole, H.; Ginnane, M. K.; Millot, M.; Bellenbaum, H.; Collins, G. W.; Hu, S. X.; Polsin, D.; Saha, R.; Topp-Mugglestone, J.; White, T. G.; Chapman, D. A.; Rygg, J. R.; Regan, S. P.; Gregori, G.
Abstract
The ionic structure of high-pressure, high-temperature fluids is a challenging theoretical problem with applications to planetary interiors and fusion capsules. Here we report a multimessenger platform using velocimetry and in situ angularly and spectrally resolved x-ray scattering to measure the thermodynamic conditions and ion structure factor of materials at extreme pressures. We document the pressure, density, and temperature of shocked silicon near 100 GPa with uncertainties of 6%, 2%, and 20%, respectively. The measurements are sufficient to distinguish between and rule out some ion screening models.
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Physical Review Research 6(2024)2, 023144
DOI: 10.1103/PhysRevResearch.6.023144
Cited 2 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39077
A matter of performance & criticality: a review of rare-earth-based magnetocaloric intermetallic compounds for hydrogen liquefaction
Liu, W.; Gottschall, T.; Scheibel, F.; Bykov, E.; Aubert, A.; Fortunato, N.; Beckmann, B.; Döring, A. M.; Zhang, H.; Skokov, K.; Gutfleisch, O.
Abstract
The low efficiency of conventional liquefaction technologies based on the Joule-Thomson expansion makes liquid hydrogen currently not attractive enough for large-scale energy-related technologies that are important for the transition to a carbon-neutral society. Magnetocaloric hydrogen liquefaction has great potential to achieve higher efficiency and is therefore a crucial enabler for affordable liquid hydrogen. Cost-effective magnetocaloric materials with large magnetic entropy and adiabatic temperature changes in the temperature range of 77 ∼ 20 K under commercially practicable magnetic fields are the foundation for the success of magnetocaloric hydrogen liquefaction. Heavy rare-earth-based magnetocaloric intermetallic compounds generally show excellent magnetocaloric performances, but the heavy rare-earth elements (Gd, Tb, Dy, Ho, Er, and Tm) are highly critical in resources. Yttrium and light rare-earth elements (La, Ce, Pr, and Nd) are relatively abundant, but their alloys generally show less excellent magnetocaloric properties. A dilemma appears: higher performance or lower criticality? In this review, we study how cryogenic temperature influences magnetocaloric performance by first reviewing heavy rare-earth-based intermetallic compounds. Next, we look at light rare-earth-based, "mixed" rare-earth-based, and Gd-based intermetallic compounds with the nature of the phase transition order taken into consideration, and summarize ways to resolve the dilemma.
Involved research facilities
- High Magnetic Field Laboratory (HLD)
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Journal of Alloys and Compounds 995(2024), 174612
DOI: 10.1016/j.jallcom.2024.174612
arXiv: https://arxiv.org/abs/2405.01128
Cited 17 times in Scopus
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Permalink: https://www.hzdr.de/publications/Publ-39076
Scalability Study on [133La]LaCl3 Production with a Focus on Potential Clinical Applications
Brühlmann, S. A.; Walther, M.; Blei, M. K.; Mamat, C.; Kopka, K.; Freudenberg, R.; Kreller, M.
Abstract
Background
In recent years, targeted alpha therapy gained importance in the clinics, and in particular, the alpha-emitter 225Ac plays a fundamental role in its clinical development. Nevertheless, no real surrogate has been established for diagnosis that would share similar chemical properties with this alpha-emitting radionuclide. In fact, the race to launch a diagnostic radionuclide to form a matched pair with 225Ac is still open, and 133La features attractive radiation properties to reclaim this place. Moreover, in order to guarantee a safe translation into the clinics, upscaling of the production of this PET radionuclide is needed.
Results
A study on optimal irradiation parameters, separation conditions and an exhaustive product characterization was carried out. In this framework, 133La activities of up to 10.7 GBq at end of bombardment for a 2 h, 60 µA and 18.7 MeV proton irradiation were produced. Moreover, the performance of four different chromatographic resins was tested and two optimized purification methods presented, taking approximately 20 minutes with a 133La recovery efficiencies of over 98%, decay corrected. High radionuclide purity and apparent molar activity was proved, of over 99.5% and 120 GBq/µmol, respectively, at end of purification. Furthermore, quantitative complexation of PSMA-617 and mcp-M-PSMA was obtained with molar activities up to 80 GBq/µmol. In addition, both formed 133La-radioconjugates proved a high stability in serum, of over (98.5 ± 0.3)% and (99.20 ± 0.08)%, respectively, for up to 24 h. First dosimetry estimation was also performed and it was calculated that an 133La application for imaging with 350 to 750 MBq injected activity would only have an effective dose of 2.1-4.4 mSv, which is comparable to that of 18F and 68Ga based radiopharmaceuticals.
Conclusions
In this article we present an overarching study on 133La production, from the radiation parameters optimization to a clinical dose estimation. Lanthanum-133 activities in the GBq range could be produced, formulated as [133La]LaCl3 with high quality regarding radiolabeling and radionuclide purity. We believe that increasing the 133La availability will further promote the development of radiopharmaceuticals based on macropa or other chelators suitable for 225Ac.
Keywords: TAT; 133La; 225Ac; macropa; Targetry; Dosimetry
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EJNMMI Radiopharmacy and Chemistry 9(2024)1, 60
DOI: 10.1186/s41181-024-00292-w
Cited 1 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39074
Proton bunch monitors for the clinical translation of prompt gamma-ray timing
Makarevich, K.; Schellhammer, S.; Pausch, G.; Römer, K.; Tiebel, J.; Turko, J. A. B.; Wagner, A.; Kögler, T.
Abstract
Objective: Prompt gamma-ray timing is an emerging technology in the field of particle therapy treatment verification. This system measures the arrival times of gamma rays produced in the patient body and uses the cyclotron radio frequency signal as time reference for the beam micro-bunches. Its translation into clinical practice is currently hindered by observed instabilities in the phase relation between the cyclotron radio frequency and the measured arrival time of prompt gamma rays. To counteract this, two proton bunch monitors are presented, integrated into the prompt gamma-ray timing workflow and evaluated. Approach: The two monitors are (a) a diamond detector placed at the beam energy degrader, and (b) a cyclotron monitor signal measuring the phase difference between dee current and voltage. First, the two proton bunch monitors as well as their mutual correlation were characterized. Then, a prompt gamma-ray timing measurement was performed aiming to quantify the present magnitude of the phase instabilities and to evaluate the ability of the proton bunch monitors to correct for these instabilities. Main results: It was found that the two new monitors showed a very high correlation for intermediate proton energies after the first second of irradiation, and that they were able to reduce fluctuations in the detected phase of prompt gamma rays. Furthermore, the amplitude of the phase instabilities had intrinsically decreased from about 700 ps to below 100 ps due to cyclotron upgrades. Significance : The uncertainty of the prompt gamma-ray timing method for proton treatment verification was reduced. For routine clinical application, challenges remain in accounting for detector load effects, temperature drifts and throughput limitations.
Keywords: proton therapy; treatment verification; proton bunch monitor; diamond detector; cyclotron monitor signal; prompt gamma-ray timing
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- OncoRay
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 39073) publication
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Experimental data for investigating proton bunch monitors for clinical …
ROBIS: 39104 HZDR-primary research data are used by this (Id 39073) publication -
Experimental data for investigating proton bunch monitors for clinical …
RODARE: 2872 HZDR-primary research data are used by this (Id 39073) publication
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Physics in Medicine and Biology 69(2024), 225013
DOI: 10.1088/1361-6560/ad8c96
Permalink: https://www.hzdr.de/publications/Publ-39073
Data publication: Defectivity of Al:ZnO Thin Films with Different Crystalline Order Probed by Positron Annihilation Spectroscopy
Magrin Maffei, R.; Butterling, M.; Liedke, M. O.; D’Addato, S.; Di Bona, A.; Bertoni, G.; Gazzadi, G. C.; Mariazzi, S.; Wagner, A.; Brusa, R. S.; Benedetti, S.
Abstract
Positronen-Lebensdauer-Messungen gewonnen an der Positronen-Strahlanlage MePS (pELBE), August 2023 Doppler-Verbreiterungs-Messungen gewonnen an der Positronen-Strahlanlage SPONSOR (pELBE), September 2023
Keywords: Positron Annihilation; MePS; SPONSOR; AZO; AlZnO; PALS; VEPALS; VEPAS
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- P-ELBE
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 39072) publication
- DOI: 10.1016/j.apsusc.2024.160240 references this (Id 39072) publication
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Defectivity of Al:ZnO Thin Films with Different Crystalline Order Probed by …
ROBIS: 39069 has used this (Id 39072) publication of HZDR-primary research data
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Reseach data in the HZDR data repository RODARE
Publication date: 2024-05-08 Closed access
DOI: 10.14278/rodare.2857
Versions: 10.14278/rodare.2858
Downloads
Permalink: https://www.hzdr.de/publications/Publ-39072
Defectivity of Al:ZnO Thin Films with Different Crystalline Order Probed by Positron Annihilation Spectroscopy
Magrin Maffei, R.; Butterling, M.; Liedke, M. O.; D’Addato, S.; Di Bona, A.; Bertoni, G.; Gazzadi, G. C.; Mariazzi, S.; Wagner, A.; Brusa, R. S.; Benedetti, S.
Abstract
Three Positron Annihilation Spectroscopy (PAS) techniques have been employed to investigate the point defects of Al-doped Zinc Oxide
(AZO) thin films grown by Radio Frequency (RF) magnetron sputtering with different substrates and deposition parameters. The films
were grown with thickness varying from 100 to 300 nm, and their crystalline quality ranged from single crystalline epitaxial to partially
amorphous. We found that the main defect in the crystalline samples is the 3VZn-VO four vacancy complex, with a concentration around
1E18−1E19 cm−3. In polycrystalline films larger vacancy clusters, within 10%−20% of the total concentration, were detected. These vacancy
clusters are inferred to be most likely located at the grain boundaries. In partially amorphous films the concentration of these larger vacancy
clusters, located either at grain boundaries or in the amorphous regions of the film, approached even the 40%, and also some sub-nano voids
have been observed.
Keywords: Positron Annihilation Spectroscopy; PALS; AlZnO; AZO; PALS; VEPALS; VEPAS
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- P-ELBE
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 39069) publication
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Data publication: Defectivity of Al:ZnO Thin Films with Different Crystalline …
ROBIS: 39072 HZDR-primary research data are used by this (Id 39069) publication
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Applied Surface Science 665(2024), 160240
DOI: 10.1016/j.apsusc.2024.160240
Permalink: https://www.hzdr.de/publications/Publ-39069
Prompt Gamma-Ray Timing for Proton Treatment Verification Under Close-to-Clinical Conditions
Makarevich, K.; Kieslich, A. M.; Römer, K.; Schellhammer, S.; Turko, J. A. B.; Wagner, A.; Kögler, T.
Abstract
Introduction
Prompt gamma-ray timing (PGT) uses the time-of-flight information of proton-induced gamma rays to reconstruct the proton range. It is currently undergoing translation into clinical application, and here we report on the latest results from evaluating the PGT in quasi-clinical scenarios for range verification purpose.
Materials & Methods
An anthropomorphic head phantom received irradiation with a clinical treatment plan. Plastic plates of different thicknesses introduced into the beam path simulated range deviations. Full-field and half-field coverages with the plates were considered. Outcomes (area under the PGT distribution) from six available detectors were summed for an augmented result. Linear model was implemented to describe the behaviour of the selected PGT feature. Data from the full field shielded formed training datasets, while measurements of half-field coverages contributed to validation datasets.
Results
Qualitatively, PGT reveals differences between covered and uncovered parts of the treatment field, however, on a quantitative level, reconstructed range deviations do not always consistently correlate with the introduced ones (Figure 1). This discrepancy can be attributed to the range mixing at plate edges as well as different initial irradiation conditions (specifically, activation count rate) for both datasets.
Summary
Combining PGT data from six detectors disclosed proton range deviations up to 2 mm using only one PGT feature. To improve the prediction accuracy and robustness, future work will look into adding more detectors and combining different features into the model. This approach will be explored in the upcoming studies.
Keywords: Prompt gamma-ray timing; Proton treatment verification; Proton range; PGT
Involved research facilities
- OncoRay
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Lecture (Conference)
5th European Congress of Medical Physics, 11.-14.09.2024, Munich, Germany
Permalink: https://www.hzdr.de/publications/Publ-39068
Simplified Beam Hardening Correction for Ultrafast X-ray CT Imaging of Binary Granular Mixtures
Bieberle, M.; Papapetrou, T. N.; Lecrivain, G.; Windisch, D.; Bieberle, A.; Wagner, M.; Hampel, U.
Abstract
Ultrafast X-ray computed tomography is an advanced imaging technique for multiphase flows. It has been used with great success for studying gas–liquid as well as gas–solid flows. Here, we apply this technique to analyze density-driven particle segregation in a rotating drum as an exemplary use case for analyzing industrial particle mixing systems. As glass particles are used as the denser of two granular species to be mixed, beam hardening artefacts occur and hamper the data analysis. In the general case of a distribution of arbitrary materials, the inverse problem of image reconstruction with energy-dependent attenuation is often ill-posed. Consequently, commonly known beam hardening correction algorithms are often quite complex. In our case, however, the number of materials is limited. We therefore propose a correction algorithm simplified by taking advantage of the known material properties, and demonstrate its ability to improve image quality and subsequent analyses significantly.
Keywords: beam hardening; computed tomography; image reconstruction; ultrafast measurement; granular media; particle mixing; rotating drum
Involved research facilities
- ROFEX
Related publications
-
Data and code: Investigating binary granular mixing in a rotating drum using …
ROBIS: 36765 HZDR-primary research data are used by this (Id 39067) publication -
Data and code: Investigating binary granular mixing in a rotating drum using …
RODARE: 2505 HZDR-primary research data are used by this (Id 39067) publication
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Sensors 24(2024), 2964
DOI: 10.3390/s24102964
Cited 2 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39067
Data publication: Revealing the 3D structure of microbunched plasma-wakefield-accelerated electron beams
La Berge, M.; Bowers, B.; Chang, Y.-Y.; Couperus Cabadag, J.; Debus, A.; Hannasch, A.; Pausch, R.; Schöbel, S.; Tiebel, J.; Ufer, P.; Willmann, A.; Zarini, O.; Zgadzaj, R.; Lumpkin, A.; Schramm, U.; Irman, A.; Downer, M.
Abstract
This repository contains data on coherent optical transition radiation (COTR) from laser wakefield accelerated electron beams. This includes raw (COTR) images and electron spectra, as well as analysis code for evaluating the COTR data and using it as an input for a differential-evolution-based reconstruction of the electron bunch.
Keywords: Laser wakefield acceleration; Laser plasma acceleration; Transition radiation; Differential evolution; Coherent transition radiation; Coherent optical transition radiation; Microbunching
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- Draco
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 39065) publication
-
Reseach data in the HZDR data repository RODARE
Publication date: 2024-05-06 Open access
DOI: 10.14278/rodare.2855
Versions: 10.14278/rodare.2856
License: CC-BY-4.0
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Permalink: https://www.hzdr.de/publications/Publ-39065
Control of the Hydroquinone/Benzoquinone Redox State in High-Mobility Semiconducting Conjugated Coordination Polymers
Huang, X.; Li, Y.; Fu, S.; Ma, C.; Lu, Y.; Wang, M.; Zhang, P.; Li, Z.; He, F.; Huang, C.; Liao, Z.; Zou, Y.; Zhou, S.; Helm, M.; Petkov, P. S.; Wang, H. I.; Bonn, M.; Li, J.; Xu, W.; Dong, R.; Feng, X.
Abstract
Conjugated coordination polymers (c-CPs) are unique organic–inorganic hybrid semiconductors with intrinsically high electrical conductivity and excellent charge carrier mobility. However, it remains a challenge in tailoring electronic structures, due to the lack of clear guidelines. Here, we develop a strategy wherein controlling the redox state of hydroquinone/benzoquinone (HQ/BQ) ligands allows for the modulation of the electronic structure of c-CPs while maintaining the structural topology. The redox-state control is achieved by reacting the ligand TTHQ (TTHQ=1,2,4,5-tetrathiolhydroquinone) with silver acetate and silver nitrate, yielding Ag4TTHQ and Ag4TTBQ (TTBQ=1,2,4,5-tetrathiolbenzoquinone), respectively. In spite of sharing the same topology consisting of a two-dimensional Ag−S network and HQ/BQ layer, they exhibit different band gaps (1.5 eV for Ag4TTHQ and 0.5 eV for Ag4TTBQ) and conductivities (0.4 S/cm for Ag4TTHQ and 10 S/cm for Ag4TTBQ). DFT calculations reveal that these differences arise from the ligand oxidation state inhibiting energy band formation near the Fermi level in Ag4TTHQ. Consequently, Ag4TTHQ displays a high Seebeck coefficient of 330 μV/K and a power factor of 10 μW/m ⋅ K2, surpassing Ag4TTBQ and the other reported silver-based c-CPs. Furthermore, terahertz spectroscopy demonstrates high charge mobilities exceeding 130 cm2/V ⋅ s in both Ag4TTHQ and Ag4TTBQ.
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Angewandte Chemie - International Edition 63(2024), e202320091
DOI: 10.1002/anie.202320091
Cited 4 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39064
Data publication: Static and dynamic properties of noncollinear magnetized ferromagnetic films
Jiménez-Bustamante, J.; Lindner, A. A.; Koyun Yücel, H. N.; Salikhov, R.; Lenz, K.; Lindner, J.; Gallardo, R. A.
Abstract
Research data of the publication (FMR, VSM).
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- DOI: 10.1103/PhysRevB.109.094403 references this (Id 39062) publication
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Static and dynamic properties of noncollinear magnetized ferromagnetic films
ROBIS: 39061 has used this (Id 39062) publication of HZDR-primary research data
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Reseach data in the HZDR data repository RODARE
Publication date: 2024-05-07 Closed access
DOI: 10.14278/rodare.2853
Versions: 10.14278/rodare.2854
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Permalink: https://www.hzdr.de/publications/Publ-39062
Static and dynamic properties of noncollinear magnetized ferromagnetic films
Jiménez-Bustamante, J.; Lindner, A. A.; Koyun Yücel, H. N.; Salikhov, R.; Lenz, K.; Lindner, J.; Gallardo, R. A.
Abstract
The dynamic matrix method was employed to perform theoretical calculations for investigating both static and
dynamic characteristics of thick ferromagnetic films. This approach considers situations where a noncollinear
equilibrium magnetization exists along the thickness due to a thickness-dependent uniaxial anisotropy and inter-
facial interactions in a synthetic antiferromagnet. In the former scenario, the study exposes a correlation between
noncollinear static magnetization and a nonmonotonic dependence of ferromagnetic resonance frequency, where
a frequency decrease is observed at low fields in the unsaturated regime. Regarding the synthetic antiferromagnet
structure, the research demonstrates noncoherent magnetization rotation in the spin-flop regime, with twisted
magnetization states influencing the critical and nucleation fields that define the spin-flop region. The results of
the investigation were compared to the macrospin approach, where the magnetization is assumed to be uniform
along the thickness. The study suggests that the contribution of noncollinear magnetic moments may mimic the
role of the biquadratic interaction in the macrospin model, implying that such a biquadratic term may be over-
estimated in coupled ferromagnetic films with thicknesses exceeding the material’s intrinsic exchange length.
Finally, the model was compared with experimental data obtained from a Py/Ir/Py synthetic antiferromagnet,
demonstrating that the theoretical consideration of a twisting equilibrium state of the magnetization precisely
reproduces the observed dynamic and static properties of the nanostructure.
Related publications
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Data publication: Static and dynamic properties of noncollinear magnetized …
ROBIS: 39062 HZDR-primary research data are used by this (Id 39061) publication
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Physical Review B 109(2024), 094403
DOI: 10.1103/PhysRevB.109.094403
Cited 1 times in Scopus
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- Secondary publication expected from 04.03.2025
Permalink: https://www.hzdr.de/publications/Publ-39061
ASTM interlaboratory study on tensile testing of AM deposited and wrought steel using miniature specimens
Dzugan, J.; Lucon, E.; Koukolikova, M.; Li, Y.; Rzepa, S.; Yasin, M. S.; Shao, S.; Shamsaei, N.; Seifi, M.; Lodeiro, M.; Lefebvre, F.; Mayer, U.; Olbricht, J.; Houska, M.; Mentl, V.; You, Z.
Abstract
An interlaboratory study, involving eigth international laboratories and coordinated by COMTES FHT (Czech Republic), was conducted to validate tensile measurements obtained using miniature specimens on additively manufactured (AM) components and artifacts. In addition to AM 316L stainless steel (316L SS), a wrought highstrength steel (34CrNiMo6V, equivalent to AISI 4340) was also used. Based on the results, a precision statement in accordance with ASTM E691 standard practice was developed, intended for inclusion in a proposed annex to
the ASTM E8/E8M tension testing method. The primary outcomes of the study highlighted the agreement between yield and tensile strength measured from miniature and standard-sized tensile specimens. Furthermore, most tensile properties exhibited similar standard deviations, offering users insight into the efficacy of miniature specimen applications.
Keywords: 316L stainless steel; Additive manufacturing; High-strength steel; Miniature specimens; Tensile tests
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Theoretical and Applied Fracture Mechanics 131(2024), 104410
DOI: 10.1016/j.tafmec.2024.104410
Cited 4 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39060
Controlling Mixed-Valence States of Pyridyldiimino-bis(o-phenolato) Ligand Radical in Uranyl(VI) Complexes
Takeyama, T.; Tsushima, S.; Takao, K.
Abstract
Combination of a uranyl(VI) ion (UVIO22+) with a redox-active ligand results in characteristic electronic structures that cannot be achieved by either component alone. In this study, three UVIO22+ complexes that bear symmetric or asymmetric 2,6-diiminopyridine-based ligands were synthesized and found to exhibit a first redox couple between −1.17 V and −1.31 V (vs. Fc0/+) to afford singly reduced complexes. The unique electronic transitions of the singly reduced UVIO22+ complexes observed in the NIR region allowed us to combine spectroelectrochemistry and time-dependent density functional theory (TD-DFT) calculations to determine the redox-active site in these UVIO22+ complexes, i.e., to clarify the distribution of the additional unpaired electron. By exploiting the push–pull effect of electron-donating and -withdrawing substituents, the ligand-based π-radical of the singly reduced UVIO22+ complexes, which tends to delocalize over the ligand, can be localized to specific sites.
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Dalton Transactions 53(2024), 16671-16684
DOI: 10.1039/D4DT01821D
Cited 1 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39059
Cell-Type-Dependent Recruitment Dynamics of FUS Protein at Laser-Induced DNA Damage Sites
Niu, Y.; Pal, A.; Szewczyk, B.; Japtok, J.; Naumann, M.; Glaß, H.; Hermann, A.
Abstract
Increased signs of DNA damage have been associated to aging and neurodegenerative diseases. DNA damage repair mechanisms are tightly regulated and involve different pathways depending on cell types and proliferative vs. postmitotic states. Amongst them, fused in sarcoma (FUS) was reported to be involved in different pathways of single- and double-strand break repair, including an early recruitment to DNA damage. FUS is a ubiquitously expressed protein, but if mutated, leads to a more or less selective motor neurodegeneration, causing amyotrophic lateral sclerosis (ALS). Of note, ALS-causing mutation leads to impaired DNA damage repair. We thus asked whether FUS recruitment dynamics differ across different cell types putatively contributing to such cell-type-specific vulnerability. For this, we generated engineered human induced pluripotent stem cells carrying wild-type FUS-eGFP and analyzed different derivatives from these, combining a laser micro-irradiation technique and a workflow to analyze the real-time process of FUS at DNA damage sites. All cells showed FUS recruitment to DNA damage sites except for hiPSC, with only 70% of cells recruiting FUS. In-depth analysis of the kinetics of FUS recruitment at DNA damage sites revealed differences among cellular types in response to laser-irradiation-induced DNA damage. Our work suggests a cell-type-dependent recruitment behavior of FUS during the DNA damage response and repair procedure. The presented workflow might be a valuable tool for studying the proteins recruited at the DNA damage site in a real-time course.
Keywords: cell type; DNA damage; FUS; human induced pluripotent stem cells; laser micro irradiation; kinetics
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International Journal of Molecular Sciences 25(2024)6, 3526
DOI: 10.3390/ijms25063526
Cited 2 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39057
Evaluation of [18F]JHU94620-d8 for imaging brain cannabinoid type 2 receptors in rodents and non-human primates
Maqbool, M.; Gündel, D.; Cureton, R.; Hong, J.; Pamie-George, M. T.; Lee, A. C.; Parcon, P.; Wu, S.; Zogbhi, S. S.; Liow, J.-S.; Pike, V. W.; Moldovan, R.-P.; Innis, R. B.
Abstract
1Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, 10 Center Drive, Bethesda, MD, 20892, USA (Email: xxx)
2Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, 04318 Leipzig, Germany
*Authors contributed equally to this work.
Background
Positron emission tomography (PET) imaging of cannabinoid receptor type 2 (CB2R) has been challenging because selective and metabolically stable PET tracers have thus far been unavailable. Here, we describe [18F]JHU94620-d8, a deuterated isotopologue of [18F]JHU94620, which was purposely designed to image CB2R with improved metabolic stability in rodents and non-human primates.
Methods
[18F]JHU94620-d8 was radiolabeled from its bromobutane-d8 precursor by reacting with [18F]F–K2.2.2. in CH3CN at 80°C for 15 minutes. PET imaging was performed in 6 male Sprague Dawley rats and a rhesus macaques after intravenous injection of [18F]JHU94620-d8 at high molar activity and radiochemical purity under baseline and blocked conditions. Cold parent (1.5 mg/kg) was used as a blocking agent. The efflux transporter substrate potential of the tracer was also assessed in mice with dual P-glycoprotein (P-gp)/breast cancer resistance protein (BCRP) transporter knockout. Ex vivo experiments were performed in rats (n=3) to check for brain parent and radiometabolite concentrations at 30 min post-radioligand injection. Tracer uptake was also evaluated in a rat model of inflammation induced by lipopolysaccharide (LPS) (50 µg in 5µL) injected into the right striatum at Days 1, 9, and 15 post-LPS injection (n=6).
Results
In rats under baseline and blocked conditions, [18F]JHU94620-d8 displayed rapid uptake and quick washout. No blocking effect was observed with cold parent. In monkeys, peak brain uptake was higher in blocked versus baseline conditions (4.8 vs. 3.4 standardized uptake value (SUV)), and both conditions had similarly rapid washout, indicating low specific binding to CB2R. The tracer showed no substrate effect in dual efflux transporter knockout mice. There was no specific uptake of [18F]JHU94620-d8 in the LPS-injected rats at Days 1, 9, or 15, and high CB2R expression was confirmed by Western Blot of brain tissue from animals with the highest expression on Day 15. The ex vivo rat study found that the tracer was stable in in vitro plasma, with radiometabolites present in plasma and spleen as well as in the brain with a peripheral origin .
Conclusion
Although [18F]JHU94620-d8 generates fewer radiometabolites than its non-deuterated analogues, its usefulness requires further evaluation in pathological models of CB2R overexpression. A more potent and selective PET radiotracer for imaging CB2R may be desirable
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Poster
NRM2024, 18.05.2024, Montreal, Kanada
Permalink: https://www.hzdr.de/publications/Publ-39055
Quantitative consideration of heterogeneities in crystalline rocks within geochemical simulations: a modular workflow
Duckstein, A.; Pospiech, S.; Brendler, V.
Abstract
The understanding and numerical modelling of hydrogeochemical processes is essential for the assessment of contaminant migration in groundwater systems, including applications in hazardous waste disposal. The SANGUR project deals with the question, which methods and parameters are relevant for the reactive transport with special focus on heterogeneities in crystalline rocks. Here, we are developing a workflow that combines data acquisition with geostatistical approaches and model reduction based on sensitivity analysis. Finally, this shall improve forecasting radionuclide retention in the far field of a nuclear waste repository.
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Article, self-published (no contribution to HZDR-Annual report)
Forschungszentrum Rossendorf 2024
ISSN: 2191-8708, eISSN: 2191-8716
Permalink: https://www.hzdr.de/publications/Publ-39054
Effects of Geometry and Topology in Curvilinear Magnetism
Abstract
The behaviour of any physical system is determined by the order parameter whose distribution is governed by the geometry of the physical space of the object, in particular its dimensionality and curvature [1]. Curvilinear magnetism is a framework, which helps understanding the impact of geometrical curvature on complex magnetic responses of curved 1D wires and 2D shells [2-4]. The lack of inversion symmetry and emergence of curvature induced anisotropy and Dzyaloshinskii-Moriya interaction (DMI) stemming from the exchange interaction [5,6] are characteristic of curved surfaces. Recently, a non-local chiral symmetry breaking was discovered [7], which is responsible for the coexistence and coupling of multiple magnetochiral properties within the same magnetic object [8]. 3D shaped magnetic objects enable realization of non-linear systems accommodating multiple solitons with complex interactions. Those are relevant for numerous research and technology fields ranging from non-conventional computing, spin-wave splitters for low-energy magnonics, superconducting electronics and small scale robotics. In our recent work, we combined theory, simulations and experimental explorations to demonstrate that magnetic vortices and antivortices can be stabilised in magnetic wireframe structures prepared using nanoscale direct writing methods like focused electron beam induced deposition [9]. This method allows designing magnetic wireframes with arbitrary complexity including helices, tripods, tetrapods, cube-shaped or buckyball-shaped architectures. The unique feature is that magnetic wireframes can support large number of vortices and antivortices. The fundamental beauty is that the topological properties of the surface of the wireframe object determine uniquely the number and type of magnetic solitons. For instance, magnetic N-pod is topologically equivalent to a sphere and hence can support N vortices and N-2 antivortices (i.e., 2N-2 magnetic solitons per object). Even more interesting is that it is possible to realise objects with topology of N-torus, which can support only one type of magnetic solitons. Yet these are antivortices but not vortices. In 3D geometries, the prevailing type of magnetic solitons is antivortices rather than vortices. For instance, 4-torus supports 6 antivortices only. The key aspect is that these are solitons of the same type which do not annihilate upon interaction. Hence, they are attractive for implementation of reservoir and neuromorphic computing. In particular, the stability of antivortex lattices combined with spin-wave propagation into wireframe structures may be useful for potential application in magnonic-based computing. Moreover, the direct integration of nanofabricated 3D wireframes into standard 2D lithographically created systems with coplanar or Ω-shaped antennas or detectors should allow extending unconventional computing into 3D offering additional functionalities such as a higher degree of interconnectivity.
[1] P. Gentile et al.; Electronic materials with nanoscale curved geometries; Nature Electronics (review) 2022 5, 551.
[2] D. Makarov et al.; Curvilinear micromagnetism: from fundamentals to applications (Springer, Zurich, 2022).
[3] D. Makarov et al.; New dimension in magnetism and superconductivity: 3D and curvilinear nanoarchitectures; Adv. Mat. (review) 2022 34, 2101758.
[4] D. Sheka et al.; Fundamentals of curvilinear ferromagnetism: statics and dynamics of geometrically curved wires and narrow ribbons; Small (review) 2022 18, 2105219.
[5] Y. Gaididei et al.; Curvature effects in thin magnetic shells; Phys. Rev. Lett. 2014 112, 257203.
[6] O. Volkov et al.; Experimental observation of exchange-driven chiral effects in curvilinear magnetism; Phys. Rev. Lett. 2019 123, 077201.
[7] D. Sheka et al.; Nonlocal chiral symmetry breaking in curvilinear magnetic shells; Commun. Phys. 2020 3, 128.
[8] O. Volkov et al.; Chirality coupling in topological magnetic textures with multiple magnetochiral parameters; Nature Com. 2023 14, 1491.
[9] O. Volkov et al.; Three-dimensional magnetic nanotextures with high-order vorticity in soft magnetic wireframes; Nature Com. 2024 15, 2193.
Keywords: curvilinear magnetism; magnetic solitons
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
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- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 39053) publication
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Invited lecture (Conferences)
9th International Workshop on Focused Electron Beam Induced Processing (FEBIP), 21.-24.07.2024, Frankfurt, Germany
Permalink: https://www.hzdr.de/publications/Publ-39053
Tailoring dielectric permittivity of epitaxial Gd-doped CeO2−x films by ionic defects
Palliotto, A.; Wu, Y.; Rata, A. D.; Herklotz, A.; Zhou, S.; Dörr, K.; Muralt, P.; Park, D.-S.
Abstract
Engineering materials with highly tunable physical properties in response to external stimuli is a cornerstone strategy for advancing energy technology. Among various approaches, engineering ionic defects and understanding their roles are essential in tailoring emergent material properties and functionalities. Here, we demonstrate an effective approach for creating and controlling ionic defects (oxygen vacancies) in epitaxial Gd-doped CeO2−x (CGO)(001) films grown on Nb:SrTiO3(001) single crystal. Our results exhibit a significant limitation in the formation of excess oxygen vacancies in the films during high-temperature film growth. However, we have discovered that managing the oxygen vacancies in the epitaxial CGO(001) films is feasible using a two-step film growth process. Subsequently, our findings show that manipulating excess oxygen vacancies is a key to the emergence of giant apparent dielectric permittivity (e.g. 106) in the epitaxial films under electrical field control. Overall, the strategy of tuning functional ionic defects in CGO and similar oxides is beneficial for various applications such as electromechanical, sensing, and energy storage applications.
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 39052) publication
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Journal of Physics: Energy 6(2024), 025005
DOI: 10.1088/2515-7655/ad2452
Permalink: https://www.hzdr.de/publications/Publ-39052
Rise and fall of the ferromagnetism in CrSBr flakes by non-magnetic ion irradiation
Long, F.; Li, Y.; Cheng, Y.; Mosina, K.; Kentsch, U.; Sofer, Z.; Prucnal, S.; Helm, M.; Zhou, S.
Abstract
We explore the magnetic phase transition in CrSBr flakes through non-magnetic ion irradiation, revealing a novel method for magnetic control in two-dimensional (2D) materials. We observe the rise and fall of the ferromagnetic phase in antiferromagnetic CrSBr with increasing the irradiation fluence. The irradiated CrSBr shows ferromagnetic critical temperature ranging from 110 to 84 K, well above liquid N2 temperature. Raman spectroscopy reveals phonon softening, suggesting the formation of defects. These findings not only highlight CrSBr's potential in spintronics, but also present ion irradiation as a precise tool for tuning magnetic properties in 2D materials, opening new avenues for the development of spintronic devices based on air-stable van der Waals semiconductors.
Keywords: CrSBr; Ferromagnetism; Ion irradiation; Phase transition; Modification
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 39051) publication
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Advanced Physics Research 3(2024), 2400053
DOI: 10.1002/apxr.202400053
Permalink: https://www.hzdr.de/publications/Publ-39051
Nonaxisymmetric modes of magnetorotational and possible hydrodynamical instabilities in the upcoming DRESDYN-MRI experiments: Linear and nonlinear dynamics
Mishra, A.; Mamatsashvili, G.; Stefani, F.
Abstract
The quest for an unambiguous detection of magnetorotational instability (MRI) in experiments is still ongoing despite recent promising results. To conclusively identify MRI in the laboratory, a large cylindrical Taylor-Couette experiment with liquid sodium is under construction within the DRESDYN project. Recently, we have analyzed the nonlinear dynamics and scaling properties of axisymmetric standard MRI with an axial background magnetic field in the context of the DRESDYN-MRI experiment. In this sequel paper, we investigate the linear and nonlinear dynamics of nonaxisymmetric MRI in the same magnetized Taylor-Couette flow of liquid sodium. We show that the achievable highest Lundquist Lu=10 and magnetic Reynolds Rm=40 numbers in this experiment are large enough for the linear instability of nonaxisymmetric modes with azimuthal wave number |m|=1, although the corresponding critical values of these numbers are usually higher than those for the axisymmetric mode. The structure of the ensuing nonlinear saturated state and its scaling properties with respect to Reynolds number Re are analyzed, which are important for the DRESDYN-MRI experiment having very high Re≳106. It is shown that for Re≲4×104, the nonaxisymmetric MRI modes eventually decay, since the modified shear profile of the mean azimuthal velocity due to the nonlinear axisymmetric MRI appears to be stable against nonaxisymmetric instabilities. By contrast, for larger Re≳4×104, a rapid growth and saturation of the nonaxisymmetric modes of nonmagnetic origin occurs, which are radially localized near the inner cylinder wall, forming a turbulent boundary layer. However, for all the parameters considered, the saturation amplitude of these nonaxisymmetric modes is always a few orders smaller than that of the axisymmetric MRI mode. Therefore, the results of our previous axisymmetric study on the scaling properties of nonlinear MRI states also hold when nonaxisymmetric modes are included.
Keywords: MHD; Taylor-Couette flow; Magnetorotational Instability; Turbulence
Involved research facilities
- DRESDYN DOI: 10.58065/51358
Related publications
- DOI: 10.58065/51358 is cited by this (Id 39050) publication
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Physical Review Fluids 9(2024)3, 033904
DOI: 10.1103/PhysRevFluids.9.033904
Cited 1 times in Scopus
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Permalink: https://www.hzdr.de/publications/Publ-39050
Note on Klein-Nishina effect in strong-field QED: the case of nonlinear Compton scattering
Hernandez Acosta, U.; Kämpfer, B.
Abstract
Suitably normalized differential probabilities of one-photon emission in external electromagnetic fields are compared to quantify the transit of nonlinear Compton scattering to linear Compton scattering, described by the Klein-Nishina formula, and to constant crossed field treatment. The known Klein-Nishina suppression at large energies is further enforced by increasing field intensity. In view of the Ritus-Narozhny conjecture, we demonstrate that different paths in the field intensity vs.\ energy plane towards large values of the quantum non-linearity parameter $\chi$ facilitate significantly different asymptotic dependencies, both in the Klein-Nishina regime and the constant crossed field regime
Keywords: Strong-field QED: nonlinear Compton; linear Compton scattering; Klein-Nishina effect; constant crossed field; Ritus-Narozhny conjecture
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Contribution to WWW
arXiv:2403.19034 [hep-ph]: https://arxiv.org/abs/2403.19034
DOI: 10.48550/arXiv.2403.19034
Permalink: https://www.hzdr.de/publications/Publ-39049
Effect of citrate on aqueous U(VI) speciation and U(VI) retention on Ca-bentonite
Sieber, C.; Kretzschmar, J.; Drobot, B.; Schmeide, K.; Stumpf, T.
Abstract
In nuclear waste repositories, citric acid may be present due to microbial activity or due to degradation of organic material in the waste. As citrate is able to complex a multitude of lanthanide and actinide ions as readily water soluble complexes and thus increase their mobility, additional investigations are necessary to understand whether the mobility of the radionuclides is affected in case of a water ingress into the repository. Because of the repository’s concrete infrastructure, high-pH conditions may form due to leaching. For low-pH systems, interaction of U(VI) with citrate has been studied extensively[1], however complexation data at higher pH is scarce. This study aims to understand the interactions of U(VI) and citrate in alkaline media. Interactions with the geotechnical barrier, in the form of bentonite (potential backfill material) are also investigated.
This study utilizes nuclear magnetic resonance (NMR) spectroscopy, UV-Vis spectroscopy, and time-resolved laser-induced fluorescence spectroscopy (TRLFS) to obtain information about the aqueous U(VI) citrate complexes as well as U(VI) retention on Ca-bentonite. NMR spectroscopy allows for gathering of structural information regarding the ligand. Complementary, TRLFS can show structural information about the complex from the metal ion’s perspective. Together with UV-Vis data, these give insight on the complexes’ structures. Complexation experiments have been conducted in the pH range 9.0 - 12.4. TRLFS as well as NMR show three distinct species: presumably two trinuclear species of different U:Cit ratio, and a mononuclear uranyl hydroxo citrate complex species. The trinuclear complexes decrease in concentration with increasing pH, where the monomeric complex becomes dominant. For pH > 11.5 and citrate concentration and/or Cit:U ratio sufficiently low (≤ 10 mM) the monomeric citrate complex begins to be displaced by citrate-free uranyl hydroxo species (likely UO2(OH)3− and UO2(OH)4 2−), along with precipitate formation.
U(VI) is well retained on Ca-bentonite over a wide pH range in the absence of complexants[2]. Retention in the presence of complexing agents is expected to be reduced[3]. Citrate has been found to greatly affect U(VI) mobility if concentration is sufficiently high (≥ 10 mM). U(VI) retention experiments conducted with 50 mM citrate show a decreased retention between pH 9 and 10.5. At pH ≥ 11.5, the U(VI) retention decreases in presence and absence of organic complexants, due to predominant U(VI) hydrolysis[2].
Literature:
[1] Kretzschmar, J. et al. Inorg. Chem. 2021, 60, 7998.
[2] Philipp, T. et al. Sci. Total Environ. 2019, 676, 469.
[3] Philipp, T., U(VI) retention by Ca-bentonite and clay minerals at (hyper)alkaline conditions. Technische Universität Dresden, PhD thesis, 2019.
Keywords: U(VI); uranyl; citrate
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Lecture (Conference)
ATAS-AnXAS 2024 Joint Workshop, 07.-11.10.2024, Karlsruhe, Deutschland -
Poster
10th International Conference on Nuclear and Radiochemistry – NRC10, 25.-30.08.2024, Brighton, Großbrittanien
Permalink: https://www.hzdr.de/publications/Publ-39048
Data publication: Risk assessment for Na-Zn liquid metal batteries
Weber, N.; Duczek, C.; Monrrabal Marquez, G.; Nash, W.; Sarma, M.; Weier, T.
Abstract
The dataset contains the risk assessment table as well as certain calculations.
Related publications
- DOI: 10.12688/openreseurope.17733.1 references this (Id 39047) publication
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Risk assessment for Na-Zn liquid metal batteries
ROBIS: 38983 has used this (Id 39047) publication of HZDR-primary research data
-
Reseach data in the HZDR data repository RODARE
Publication date: 2024-05-03 Open access
DOI: 10.14278/rodare.2851
Versions: 10.14278/rodare.2852
License: CC-BY-4.0
Downloads
Permalink: https://www.hzdr.de/publications/Publ-39047
Depth-distribution of resistivity within ion-irradiated semiconductor layers revealed by low-kV scanning electron microscopy
Jóźwik, I.; Jagielski, J.; Ciepielewski, P.; Dumiszewska, E.; Piętak-Jurczak, K.; Kamiński, M.; Kentsch, U.
Abstract
Low-kV scanning electron microscopy imaging was used to visualize the 2D profiles of internal resistivity distribution in 600 keV He2+ ion-irradiated epitaxial GaAs and Al(0.55)Ga(0.45)As. The influence of the dopant concentration on DIVA (damage-induced voltage alteration) contrast formation has been studied in this paper. The threshold irradiation fluencies (the fluencies below which no damage-related contrast is observed) were defined for each studied material. The results show that the same level of damage in the material caused by ion irradiation becomes visible at lower threshold fluence in the case of lower-doped sample of the same composition. The aluminum content in the composition of materials exposed to ion irradiation and subsequent DIVA contrast formation mechanism was considered as well. The carrier concentration in irradiated layers has been studied by Raman spectroscopy and photoluminescence measurements, which confirmed that the increase of the resistivity of the material caused by ion-irradiation damage generation is resulting from the formation of deep states in the bandgap trapping free carriers.
Keywords: AIIIBV; Ion damage; Low-kV SEM
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 39046) publication
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Materials Science in Semiconductor Processing 165(2023), 107640
DOI: 10.1016/j.mssp.2023.107640
Permalink: https://www.hzdr.de/publications/Publ-39046
Approaching the Curie temperature of ferromagnetic (Ga,Mn)P prepared by ion implantation and pulsed laser melting
Tian, M.; Yang, Q.; Yuan, Y.; Kentsch, U.; Liu, K.; Tang, M.; Xie, Z.; Li, L.; Wang, M.
Abstract
This work aims to estimate the Curie temperature and critical exponents in the critical regime of III-V ferro- magnetic semiconductor (FS) (Ga,Mn)P film using various methods, including Arrott and Kouvel-Fisher plots, as well as electrical transport measurements. The (Ga,Mn)P film was prepared by implanting Mn ions into an intrinsic (001) GaP wafer, followed by pulsed laser melting (PLM). The magnetic properties of the (Ga,Mn)P layer were systematically investigated. The study investigated the accuracy of four different methods in deter- mining the critical behaviors for the magnetic properties close to TC. The results suggest that the critical ex- ponents are similar to those of the mean-field model, as indicated by the modified Arrot plots and temperature dependent effective critical exponents. However, the accuracy of the temperature-dependent resistance Rₓₓ(T) method and Kouvel-Fisher (K-F) analysis is limited due to the Gaussian distribution of Mn ions in the film.
Keywords: Magnetic properties; Ion implantation; Electrical transport; Ferromagnetic; III-V ferromagnetic semiconductors
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
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- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 39045) publication
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Results in Physics 58(2024), 107508
DOI: 10.1016/j.rinp.2024.107508
Permalink: https://www.hzdr.de/publications/Publ-39045
Prior implantation of hydrogen as a mechanism to delay helium bubbles, blistering, and exfoliation in titanium
Fink Ilyasafov, S.; Maman, N.; Kentsch, U.; Zenou, V. Y.; Vaknin, M.; Rakita, Y.; Zamir, G.; Dahan, I.; Shneck, R. Z.
Abstract
This study explores the delaying of the formation of helium bubbles and blisters in pure titanium by hydrogen pre-implantation. Titanium, implanted with helium (40 KeV, 5 × 10¹⁷ ions/cm²), exhibited large bubbles that cause exfoliation after heat treatment, whereas hydrogen pre-implantation inhibited bubble growth at room temperature and reduced the exfoliation after heat treatment.
In the samples pre-implanted with hydrogen, we found evidence of helium diffusion delay by: (a) a fourfold reduction in bubble pressure (b) faceted cavities in the samples (c) a smaller increase in titanium lattice pa- rameters (d) a 16-fold reduction in average bubble size and a sixfold reduction in bubble area fraction (e) a more than twofold decrease in exfoliation (f) a tendency toward the formation of larger bubbles as a result of heat treatment. We believe that it is reasonable to assume that the inhibition of helium diffusion between tetrahedral interstitial lattice sites takes place because of the occupation of the intermediate octahedral sites by hydrogen atoms.
Evidence for the opposite effect, that is inhibition of the diffusion of hydrogen in the presence of helium, is found in the retention of hydrogen in the specimens at elevated temperatures. This retention allowed the exis- tence of titanium hydride after heat treatment at 680 °C. The present study sheds light on the intricate interplay between hydrogen and helium in titanium, providing insights into mechanisms that can potentially mitigate helium-induced damage in materials.
Keywords: Bubble formation; Helium implantation; Pre-implantation; Plasma-facing materials (PFMs); Nuclear technology; Irradiation damage; Helium diffusion; Titanium hydride; Blisters; Surface exfoliation; Repulsive interactions; EELS
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 39044) publication
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Journal of Nuclear Materials 594(2024), 155017
DOI: 10.1016/j.jnucmat.2024.155017
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- Secondary publication expected from 13.03.2025
Permalink: https://www.hzdr.de/publications/Publ-39044
Promethium bound
Abstract
The chemistry of promethium, a rare radioactive element, has been clouded in mystery, owing to its scarcity and the
difficulties involved in working with it. The synthesis of a complex of promethium plugs this knowledge gap
Involved research facilities
- Rossendorf Beamline at ESRF DOI: 10.1107/S1600577520014265
Related publications
- DOI: 10.1107/S1600577520014265 is cited by this (Id 39043) publication
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Nature 629(2024), 765-766
DOI: 10.1038/d41586-024-01193-3
Permalink: https://www.hzdr.de/publications/Publ-39043
Sublimed fine-grained dysprosium: Significant magnetocaloric effect
Koshkidko, Y. S.; Cwik, J.; Salazar Mejia, C.; Dormidontov, N. A.; Prokofev, P. A.; Bakulina, A. S.; Nikitin, A. A.; Khomich, A. A.; Gimaev, R. R.; Andreenko, A. S.; Burmii, Z. P.; Telitsa, A. A.; Zverev, V. I.; Kolchugina, N. B.
Abstract
As is known, rare-earth metals (REMs) are promising magnetocaloric materials. The magnitude of the magnetocaloric effect (MCE) of REMs significantly depends on their purity. This paper presents results of studies of the magnetic and magnetocaloric properties of sublimed dysprosium, prepared in the course of the present study, with an emphasis on its impurity and structure perfection. The comprehensive analysis of the chemical composition of sublimed dysprosium, which was performed for the first time by atom probe tomography, showed that the metal corresponds to high-purity rare-earth metals (3 N+). The MCE effect was studied using direct measurements of the adiabatic temperature change (ΔTad) in pulsed (up to 50 T) and steady (up to 14 T) magnetic fields. The studies of the MCE of polycrystalline sublimed Dy by direct method showed that the high ΔTad value for sublimed Dy are comparable with those obtained for single-crystal Dy in magnetic fields up to 5 T. The vacuum sublimation, which is more economical and technologically advanced in contrast to single crystal growing, can be used to create magnetocaloric REM-based materials with high MCE values.
Involved research facilities
- High Magnetic Field Laboratory (HLD)
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Vacuum 225(2024), 113239
DOI: 10.1016/j.vacuum.2024.113239
Permalink: https://www.hzdr.de/publications/Publ-39042
A Co(II)-Hydroxide Complex That Converts Directly to a Co(II)-Acetamide during Catalytic Nitrile Hydration
Heim, P.; Biswas, S.; Lopez, H.; Gericke, R.; Twamley, B.; McDonald, A. R.
Abstract
In exploring structural and functional mimics of nitrile hydratases, we report the synthesis of the pseudo-trigonal bipyramidal Co(II) complexes (K)[Co(II)(DMF)(LPh)] (1(DMF)), (NMe₄)₂[Co(II)(OAc)(LPh)] (1(OAc)), and (NMe₄)₂[Co(II)(OH)(LPh)] (1(OH)) (LPh = 2,2′,2’’-nitrilo-tris-(N-phenylacetamide; DMF = N,N-dimethylformamide; −OAc = acetate)). The complexes were characterized using NMR, FT-IR, ESI-MS, electronic absorption spectroscopy, and X-ray crystallography, showing the LPh ligand to bind in a tetradentate tripodal fashion alongside the respective ancillary donor. One of the complexes, 1(OH), is an unusual structural and functional mimic of the Co active site in Co nitrile hydratases. 1(OH) reacted with acetonitrile to yield the Co(II)-acetamide complex (NMe₄)₂[Co(II)(NHC(O)CH₃)(LPh)], 2, which was also thoroughly characterized. In the presence of excess hydroxide, 1(OH) was found to catalyze quantitative conversion of the added hydroxide into acetamide. Despite the differences in Co oxidation state in nitrile hydratases and 1(OH) (Co(III) versus Co(II), respectively), 1(OH) was nonetheless an effective nitrile hydration catalyst, selectively producing acetamide over multiple turnovers.
Keywords: Anions; Hydration; Ions; Ligands; Nitrogen compounds
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Inorganic Chemistry 63(2024), 7896-7902
DOI: 10.1021/acs.inorgchem.4c00754
Permalink: https://www.hzdr.de/publications/Publ-39041
DATIV - Remote enhancement of smart aerosol measurement system using Raspberry Pi based distributed sensors
Hasanuzzaman, G.; Buchwald, T.; Schunk, C.; Egbers, C.; Schröder, A.; Hampel, U.
Abstract
Enclosed public spaces are the hotspots for airborne disease transmission. To measure and maintain indoor air quality in terms of airborne transmission, an open source, low cost and distributed array of Particulate Matter Sensors has been developed and named as Dynamic Aerosol Transport for Indoor Ventilation or DATIV system. This system can use multiple Particulate Matter Sensors (PMS) simultaneously and can be remotely controlled using a Raspberry Pie based operating system. The data acquisition system can be easily operated using the GUI within any common browser installed on a remote device such as a PC or Smartphone with corresponding IP address. The software architecture and validation measurements are presented together with possible future developments.
Keywords: particulate matter; aerosol; COVID-19; distributed sensors; Raspberry Pi; WiFi; open source; low cost measurement system; indoor ventilation
Related publications
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DATIV-Dynamic Aerosol Transport for Indoor Ventilation with Smart Array of …
ROBIS: 38035 is part of this (Id 39040) publication -
DATIV-Dynamic Aerosol Transport for Indoor Ventilation with Smart Array of …
RODARE: 2662 is part of this (Id 39040) publication -
Data publication: DATIV - Remote enhancement of smart aerosol measurement …
ROBIS: 39248 HZDR-primary research data are used by this (Id 39040) publication
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Sensors 24(2024)13, 4314
DOI: 10.3390/s24134314
Permalink: https://www.hzdr.de/publications/Publ-39040
Enhanced Photoelectrochemical Water Splitting through Synergistic Carrier Separation and Transfer in TiO2 -Ferrihydrite-MXene Nanowire Arrays
Weiguang, Y.; Dengyun, S.; Yutong, D.; Hengyue, L.; Jianming, L.; Li, Y.
Abstract
The effective separation and efficient transportation of photogenerated carriers within a photoanode are critical factors for achieving exceptional photoelectrochemical (PEC) water splitting. In this study, TiO2-Ferrihydrite (Fh) -MXene nanowire arrays (NWAs) are fabricated by hydrothermal method followed by spin-coating. TiO2-Fh-MXene NWAs achieved a photocurrent density of 1.44 mA/cm2 at 1.23 V versus reversible hydrogen electrode (vs. RHE), surpassing TiO2-Fh by 2.05 times and TiO2 by 2.93 times, respectively. According to the electrochemical impedance spectroscopy, photoluminescence and Mott-Schottky measurements, the significant enhancement in the separation of photogenerated electron-hole pairs and efficient carrier transportation are ascribed to the integration of Fh and MXene, respectively. Additionally, the light absorption of TiO2 NWAs is improved with the incorporation of the Fh-MXene layer. This work provides valuable insights into the fabrication of photoanodes, especially using wide bandgap materials.
Keywords: Ferrihydrite-MXene; Metal oxide -TiO2; Photoelectrochemical water splitting; Hole transport layer; Electron transport layer
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ACS Applied Energy Materials 7(2024)10, 4412-4420
DOI: 10.1021/acsaem.4c00308
Cited 2 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-39039
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