Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

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32337 Publications
RBS and Channeling Analysis of Cobalt Disilicide Layers Produced by Focused Ion Beam Implantation
Teichert, J.; Voelskow, M.; Bischoff, L.; Hausmann, S.;
Cobalt disilicide layers were formed by ion beam synthesis using 35 keV Co+ focused ion beam (FIB) implantation into silicon. A strong influence of the pixel dwell time on the layer formation was found. Only for short pixel dwell-times (about 1µs) closed layers with sufficient quality for device application could be formed. To understand the dwell-time effect the as-implanted samples were examined by Rutherford backscattering (RBS) and channeling analysis. A method is presented which allows quantitative measurements of samples where the implanted areas are smaller than the diameter of the RBS beam. Evidence has been obtained that the silicon crystal damage is less for short dwell-times.
  • Vacuum, Volume 51, Number 2, Pages 261-266, 1998
  • Lecture (Conference)
    10th Int. School on Vacuum, Electron and Ion Technologies, Varna, Bulgaria, Sept. 22 - 27, 1997

Publ.-Id: 1022 - Permalink


Elastic Proton-Deuteron Backward Scattering: Relativistic Effets and Polarization Observables
Kaptari, L. P.; Kämpfer, B.; Dorkin, S. M.; Semikh, S. S.;
Abstract
The elastic proton-deuteron backward reaction is analyzed within a covariant approach based on the Bethe-Salpeter equation with realistic meson-exchange interaction. Lorentz boost and other relativistic effects in the cross section and spin correlation observables, like tensor analyzing power and polarization transfer etc., are investigated in explicit form. Results of numerical calculations for a compbte set of polarization observables are presented.
  • Open Access LogoForschungszentrum Rossendorf; FZR-194
  • Physical Review C Vol. 57 (1998) 1097-1111

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Publ.-Id: 1021 - Permalink


Verification of the Code DYN3D/R with the Help of International Benchmarks
Grundmann, U.; Rohde, U.;
Different benchmarks for reactors with quadratic fuel assemblies were calculated with the code DYN3D/R. In this report comparisons with the results of the reference solutions are carried out. The results of DYN3D/R and the reference calculation for the eigenvalue keff and the power distribution are shown for the steady-state 3-dimensional IAEA-Benchmark. The results of NEACRP-Benchmarks on control rod ejections in a standard PWR were compared with the reference solutions published by the NEA Data Bank. For assessing the accuracy of DYN3D/R results in comparison to other codes the deviations to the reference solutions are considered. Detailed comparisons with the published reference solutions of the NEA-NSC Benchmarks on uncontrolled withdrawal of control rods are made. The influence of the axial nodalization is also investigated. All in all, a good agreement of the DYN3D/R results with the reference solutions can be seen for the considered benchmark problems.

  • Open Access LogoForschungszentrum Rossendorf; FZR-195 October 1997

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Publ.-Id: 1020 - Permalink


Entwicklung von theoretischen Schwingungsmodellen für WWER-Reaktoren auf der Grundlage der Finite-Elemente-Methode
Altstadt, E.; Weiß, F.-P.; Werner, M.; Bulavin, V.; Pavelko, V.; Gutsev, D.; Anikin, G.; Usanov, A.; Dodonov, V.;
In diesem Abschlußbericht wird ein Fördervorhaben beschrieben, welches auf die Unterstützung von 6 russischen Wissenschaftlern aus drei unterschiedlichen Institutionen abzielte. Ihre Arbeiten zur Anlagendiagnostik / Schadensfrüherkennung dienen der Erhöhung der Sicherheit von WWER-Reaktoren.
Das Vorhaben leistet einen Beitrag zur verbesserten Beurteilung der mechanischen Integrität von Reaktoren der russischen WWER-440 und WWER-1000 Baureihe, insbesondere zur empfindlichen Früherkennung und Lokalisation mechanischer Schädigungen an Reaktorkomponenten mit Hilfe schwingungsdiagnostischer Methoden. Zu diesem Zweck wurde das Finite-Element-Modell zur Simulation des mechanischen Schwingungsverhaltens aller Primärkreiskomponenten eines WWER-1000 erstellt. Dafür wurde das Programmpaket ANSYS® genutzt.
Das Berechnungsmodell zum WWER-440 wurde mit neueren Ergebnissen experimenteller Schwingungsuntersuchungen weiter justiert. Das Modell kann in der Hauptsache genutzt werden, um zu klären, wie sich unterstellte mechanische Defekte von Reaktoreinbauten auf die Schwingungen der Gesamtanlage auswirken. Diese Schadenssimulation ist besonders geeignet, empfindliche Meßpositionen für die on-line Überwachung zu finden und physikalisch fundierte Grenzwerte zu definieren.
  • Open Access LogoForschungszentrum Rossendorf; FZR-196 Oktober 1997

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Publ.-Id: 1019 - Permalink


Ellipsometric Investigation of Damage Distribution in Low Energy Boron Implantation of Silicon
Fukarek, W.; Möller, W.; Hatzopoulos, N.; Armour, D. G.; van den Berg, J. A.;
As the scaling of silicon devices to 100 nm channel length requires the formation of ultra-shallow (< 60 nm) junctions, high depth resolution analytical techniques become necessary for the characterization of the dopant and damage distributions. In situ single wavelength Ellipsometric
Etch Depth Profiling (EEDP) and non-destructive Variable Angle of incidence Spectroscopic Ellipsometry (VASE) have been used to obtain accurate and quantitative information on the depth profiles of radiation damage produced by low energy, room temperature ion implantation of B+ into Si.
  • Nuclear Instruments and Methods in Physics Research B 127/128 (1997) 879-883

Publ.-Id: 1018 - Permalink


Verhalten des Radiums im Flutungsprozeß des Uranbergwerks Königstein
Baraniak, L.; Thieme, M.; Funke, H.; Bernhard, G.; Nitsche, H.;
The interaction of radium with characteristic sediments of the upper Saxon Elbe river valley was investigated with the
aim to provide key data for transport modelling within the framework of mining site restoration. Adsorption
measurements therefore were carried out on site-specific sediments (different kinds of sandstone, claystone and lime
marl) using (1) acidic mine water coming from sulfuric acid residues of the former in-situ leaching process, (2)
groundwater that is inflowing into the mine and (3) mixtures of both which simulates certain stages of the mine flooding process. The distribution ratios were determined by batch experiments using an eight-week equilibration at aquifer temperature (14 °C). Radium adsorption from acidic mine water onto different kinds of sandstone is characterized by high distribution ratios (3400 mL/g). When contacted with groundwater, the sorption is decreased more than 20-fold (60-180 mL/g). For claystone and lime marl the distribution ratios amount to 130 and 480 mL/g, respectively, and they are nearly constant in the mine flooding process. The main adsorption mechanisms on the leached sandstone and the clayey sediments were identified as coprecipitation and ion exchange, respectively. The long-term migration behaviour in the aquifers of the south-east Saxon Elbe basin was calculated on the basis of Hadermanns' equation, considering retardation, dispersion and radioactive decay.
  • Wissenschaftliche Zeitschrift der TU-Dresden 46 (1997) Heft 6, S. 90-94

Publ.-Id: 1016 - Permalink


Interaction of Uranium(VI) with Arsenate in Aqueous Solution Studied by Time-Resolved Laser-Induced Fluorescence Spectroscopy (TRLFS)
Rutsch, M.; Geipel, G.; Bernhard, G.; Nitsche, H.;
  • Poster
    13th Radiochemical Conference, Marianske Lasne-Jachymov, Czech Republik, 20.-24.04.1998
  • Radiochimica Acta 86(1999), 135-141

Publ.-Id: 1014 - Permalink


Methods for Colloid Characterization in Environmental Waters Rich in Humic Substances
Zänker, H.; Richter, W.; Hüttig, G.; Schmeide, K.; Nitsche, H.;
  • Poster
    13th Radiochemical Conference, Marianske Lazne, 19-24.4.1998

Publ.-Id: 1013 - Permalink


Fine Structure of the E1 Response in 140Ce Below the Particle Threshold*
Herzberg, R.-D.; von Brentano, P.; Eberth, J.; Enders, J.; Fischer, R.; Huxel, N.; Klemme, T.; von Neumann-Cosel, P.; Nicolay, N.; Pietralla, N.; Ponomarev, V. Y.; Reif, J.; Richter, A.; Schlegel, C.; Schwengner, R.; Skoda, S.; Thomas, H. G.; Wiedenhöver, I.; Winter, G.; Zilges, A.;
The E1 response of the semi-magic nucleus 140Ce below the particle
threshold was measured in a (gamma, gamma') experiment utilizing the new
Euroball Cluster detector at the S-DALINAC. While the energy averaged data
are in good agreement with the tagged photon results, here they are resolved
for the first time into 54 individual transitions. A quasiparticle-phonon
model calculation including up to three-phonon configurations compares
well to the extracted strength distribution. The interference between one-
and two-phonon contributions is essential for a quantitative reproduction.
  • Physics Letters B 390 (1997) 49-54

Publ.-Id: 1011 - Permalink


Tilted Rotation of Weakly Deformed and Triaxial Nuclei
Frauendorf, S.;
  • Zeitschrift für Physik A 358, 163-167 (1997)

Publ.-Id: 1010 - Permalink


Dipole excitations in 122Te, 126Te and 130Te
Schwengner, R.; Schauer, W.; Winter, G.; von Brentano, P.; Eberth, J.; Enders, J.; von Egidy, T.; Grinberg, M.; Herzberg, R.-D.; Huxel, N.; Käubler, L.; von Neumann-Cosel, P.; Nicolay, N.; Ott, J.; Pietralla, N.; Prade, H.; Raman, S.; Reif, J.; Richter, A.; Schlegel, C.; Schnare, H.; Servene, T.; Skoda, S.; Stoyanov, C.; Thomas, H. G.; Wiedenhöver, I.; Zilges, A.;
Excited states of the nuclei 122Te, 126Te and 130Te
were populated via the (gamma,gamma') reaction at endpoint energies of
the bremsstrahlung between 4.5 and 5.5 MeV. Gamma rays were detected with
a EUROBALL-CLUSTER detector and a single detector. In all nuclei several
dipole transitions were identified at energies around 3 MeV. The lowest
corresponding J = 1 states are interpreted as two-phonon excitations. Quasiparticle-phonon-model
calculations predict one 1- state arising from the coupling
of the first quadrupole and the first octupole phonon and one 1+
state arising from the coupling of the first and the isovector second quadrupole
phonon at about 3 MeV. The calculated transition strengths are compatible
with experimental one.
  • Zeitschrift für Physik A 358, H.2, 197-198 (1997)

Publ.-Id: 1008 - Permalink


Particle-hole Induced Intruder Bands in117Sb and 119Sb
Lafosse, D. R.; Fossan, D. B.; Hughes, J. R.; Liang, Y.; Schnare, H.; Vaska, P.; Waring, M. P.; Zhang, J. Y.;
  • Physical Review C Volume 56, Number 2, 760-771

Publ.-Id: 1007 - Permalink


Fragmentation of the Yrast Band in 186Os at Ipi=18+ and Disappearance of the Collective Minimum
Balabanski, D. L.; Hristov, D. H.; Lieder, R. M.; Rzaca-Urban, T.; Gast, W.; Hebbinghaus, G.; Krämer-Flecken, A.; Schnare, H.; Urban, W.; Wyss, R.;
  • Zeitschrift für Physik A 356, 393-397 (1997)

Publ.-Id: 1006 - Permalink


The application of PET to quality assurance of heavy-ion tumour therapy.
Enghardt, W.; Debus, J.; Haberer, T.; Hasch, B.-G.; Hinz, R.; Jäkel, O.; Krämer, M.; Lauckner, K.; Pawelke, J.;
At the new heavy ion tumor therapy facility of the Gesellschaft für Schwerionenforschung at Darmstadt positron emission tomography (PET) has been implemented for in-beam and in-situ therapy control, i.e. during the tumor irradiation. The components necessary for this dedicated PET-imaging and their integration into the framework of therapy planning and quality assurance of heavy ion cancer treatments are presented. Results of the first application of this PET-method to patient treatments are reported.
Keywords: heavy-ion therapy, positron emission tomography, treatment planning, quality assurance
  • Strahlentherapie und Onkologie, Vol. 175, Suppl. II (1999) 33-36

Publ.-Id: 1005 - Permalink


Solution of the 4th AER Dynamic Benchmark by Use of the Code DYN3D with a Particle-in-Cell Method for the Description of Boron Transport
Rohde, U.; Lucas, D.;
The results of the 4th AER dynamic benchmark obtained by the use of the code DYN3D in the Research Centre Rossendorf are presented. The benchmark comprises the modeling of a boron dilution transient caused by switching on the first main coolant pump of a loop containing a plug of partially undiluted water. Therefore, the course of the transient is significantly affected by correct modeling of the boron transport. The results of studies on the influence of numerical diffusion during boron transport are presented. Consequently, a new numerical model based on the particle­in­cell method has been developed and implemented into DYN3D. The basic features of this model are described. It allows the complete suppression of numerical diffusion and to take into account the effect of boron enrichment in the liquid water phase in the case of boiling in a simple manner. Another important feature of the benchmark task was that each participant had to use his own macroscopic cross section library. In our analysis the MAGRU library for VVER­440 was used. A few reactor­physical key parameters had been given in the benchmark definition for optional adoptation of the cross section data. The presented analysis was carried out with a minimum amount of adoptations. Finally, only the static supercriticality of the boron dilution was given an the Doppler feedback was adopted. Some interesting thermo­hydraulic effects are discussed, which can be used for a deeper comparative analysis of the thermo­hydraulics models of the codes. Due to the low mass flow rate and high heat flux densities occuring, vapour generation during the transient is significantly affected by subcooled boiling under thermodynamic non­equlibrium conditions.

  • Lecture (Conference)
    7th Symposium of Atomic Energy Research, Hörnitz, 23. - 26. 09. 1997
  • Contribution to proceedings
    Proceedings of the 7th Symposium of Atomic Energy Research, p. 387, Hörnitz, 23. - 26. 09. 1997

Publ.-Id: 1004 - Permalink


Strong Blue and Violet Photo- and Electroluminescence from Germanium- and Silicon-Implanted Silicon Dioxide Layers
Rebohle, L.; von Borany, J.; Yankov, R. A.; Skorupa, W.; Tyschenko, I. E.; Fröb, H.; Leo, K.;
  • Applied Physics Letters, Vol. 71, Nr. 19, S. 2809-2811

Publ.-Id: 1002 - Permalink


MARS: A Start Detector System for the Cosy Time-of-Flight Spectrometer TOF
Michel, P.; Möller, K.; Naumann, B.; Naumann, L.; Schamlott, A.; Schmidt, G.; Schülke, A.;
  • Nuclear Instruments and Methods in Physics Research A 408 (1998) 453-467

Publ.-Id: 1001 - Permalink


11C-Labelling of Heterocyclic Aromatic Compounds in Ring Positions: Synthesis of 2-11C Indole
Zessin, J.; Steinbach, J.;
  • Journal of Labelled Compounds and Radiopharmaceuticals XLI, 669-676 (1998)

Publ.-Id: 1000 - Permalink


Synthesis of Oxorhenium(V) Complexes Derived from 7-alpha-Functionalized Testosterone: First Rhenium-Containing Testosterone Derivatives
Wüst, F.; Scheller, D.; Spies, H.; Johannsen, B.;
  • Eur. J. Inorg. Chem. 1998, 789-793

Publ.-Id: 999 - Permalink


In-beam PET imaging for the control of heavy-ion tumour therapy.
Pawelke, J.; Enghardt, W.; Haberer, T.; Hasch, B.-G.; Hinz, R.; Krämer, M.; Lauckner, K.; Sobiella, M.;
A method for the in-situ control of the heavy-ion tumour therapy by means of positron emission tomography is introduced. This method is founded on the measurement of the dynamic spatial distributions of beta+-emitters generated by nuclear fragmentation during the irradiation and their relation to the dose. In order to study this relationship and to derive the dose distribution from the measured beta+-activity distribution, a framework of model calculations is used. Results of phantom experiments with 12C ion beams will be presented, demonstrating good agreement between experiment and calculation as well as the possibilities and limits of the PET-technique for treatment plan verification and beam monitoring.
  • IEEE Transactions on Nuclear Science, Vol. 44, No. 4 (1997) 1492-1498
  • Lecture (Conference)
    IEEE Nuclear Science Symposium, 2-9 Nov, 1996, Anaheim, California, USA
    Conference Record, Vol. 2 (1996) 1099-1103
  • Contribution to proceedings
    IEEE Nuclear Science Symposium, 2-9 Nov, 1996, Anaheim, California, USA
    Conference Record, Vol. 2 (1996) 1099-1103

Publ.-Id: 998 - Permalink


Tilted Rotation and Backbending in an Odd-Proton Nucleus
Pearson, C. J.; Walker, P. M.; Purry, C. S.; Dracoulis, G. D.; Bayer, S.; Byrne, A. P.; Kibedi, T.; Kondev, F. G.; Shizuma, T.; Bark, R. A.; Sletten, G.; Frauendorf, S.;
  • Physical Review Letters, Volume 79, Number 4

Publ.-Id: 997 - Permalink


Fission of Metal Clusters
Näher, U.; Bjornholm, S.; Frauendorf, S.; Garcias, F.; Guet, C.;
  • Physics Reports 285 (1997) 245-320

Publ.-Id: 996 - Permalink


Identification of Excited States in Doubly Odd 110Sb: Smooth Band Termination
Lane, G. J.; Fossan, D. B.; Thorslund, I.; Vaska, P.; Allatt, R. G.; Paul, E. S.; Käubler, L.; Schnare, H.; Hibbert, I. M.; O'Brien, N.; Wadsworth, R.; Andrejtscheff, W.; de Graaf, J.; Simpson, J.; Lee, I. Y.; Macchiavelli, A. O.; Blumenthal, D. J.; Davids, C. N.; Lister, C. J.; Seweryniak, D.; Afanasjev, A. V.; Ragnarsson, I.;
Excited states in 110Sb have been identified for the first time
in a series of gamma-spectroscopy experiments using both thin and backed
targets, including neutron-fold and recoil-mass measurements to provide
unambiguous channel identification. The three decoupled intruder bands
observed in 110Sb are based upon configurations involving 2p-2h
excitations across the Z=50 shell gap and show the features of smooth band
termination. The yrast intruder band, which has been connected to the low-spin
levels, is tentatively identified up to its predicted termination at IPi=45+.
Excellent agreement with configuration-dependent cranked Nilsson-Strutinsky
calculations is obtained for the high-spin states near termination.
  • Physical Review C, Nuclear Physics, 3rd Series, Volume 55, Number 5

Publ.-Id: 995 - Permalink


Influence of the Ion Irradiation on the Properties of ß-FeSi2 Layers Prepared by Ion Beam Assisted Deposition
Barradas, N.; Panknin, D.; Wieser, E.; Schmidt, B.; Betzl, M.; Mücklich, A.; Skorupa, W.;
ß-FeSi2 was produced by ion beam assisted deposition
(IBAD). The influence of the deposition parameters on the structure was
studied by Rutherford backscattering, X-ray diffraction, cross section
transmission electron microscopy, and scanning electron microscopy. The
samples grow in a columnar way with pin-holes and their surface is rough.
A soft IBAD process with low Ar energy (EAr = 200 eV) and low Ar ion to
Fe atom ratio (IAr/AFe = 0.16) improves the layer structure in comparison
to samples prepared without Ar irradiation. Less pin-holes are formed,
and the roughness shows a minimum. The roughness increases for larger EAr
and larger IAr/AFe. All samples are polycrystalline but with a pronounced
texture. The preferential orientation is also enhanced by the IBAD process.
The electrical properties of the layers were characterized by Hall effect
measurements and measurements of the I-V characteristics of simple diode
structures. The results are discussed in relation with the influence of
the ion beam.
  • Nuclear Instruments and Methods in Physics Research B 127/128(1997) 316-320

Publ.-Id: 994 - Permalink


Pion Production in Mass-Symmetric Heavy Ion Collisions at 0.8-1.8 AGeV
Müntz, C.; Baltes, P.; Oeschler, H.; Sartorius, C.; Sturm, C.; Wagner, A.; Bormann, C.; Brill, D.; Shin, Y.; Stein, J.; Ströbele, H.; Ahner, W.; Barth, R.; Cieslak, M.; Debowski, M.; Grosse, E.; Henning, W.; Koczon, P.; Mang, M.; Miskowiec, D.; Schicker, R.; Senger, P.; Kohlmeyer, B.; Pöppl, H.; Pühlhofer, F.; Speer, J.; Völkel, K.; Walus, W.;
  • Zeitschrift für Physik A 357, 399-409 (1997)

Publ.-Id: 993 - Permalink


Jahresbericht 1995/1996 Abteilung Kommunikation und Datenverarbeitung
Fülle, R.;
  • Open Access LogoForschungszentrum Rossendorf; FZR-187

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Publ.-Id: 992 - Permalink


In-situ Investigation of Ion Drift Processes in Glass During Anodic Bonding
Schmidt, B.; Nitzsche, P.; Lange, K.; Grigull, S.; Kreißig, U.; Thomas, B.; Herzog, K.;
  • Lecture (Conference)
    EUROSENSORS XI, The 11th European Conference on Solid-State Transducers , Warzaw, Poland, Sept. 21-24, 1997
  • Sensors and Actuators A 67 (1998) 191-198

Publ.-Id: 991 - Permalink


Elektroenergieerzeugung aus erneuerbaren Energiequellen in Sachsen
Hackstein, G.; Riedel, J.; Rindelhardt, U.; Schwanitz, M.;
Im Bericht werden die Potentiale zur Elektroenergieerzeugung aus verschiedenen erneuerbaren Energiequellen in Sachsen zusammengestellt. Dabei werden natürliche Potentiale und - wo möglich - technische Potentiale sowie wirtschaftliche Potentiale unterschieden. Das ermittelte technische Potential (ohne Biomasse) entspricht etwa einer Elektroenergieproduktion von 7400 GWh jährlich. Davon entfallen etwa 2/3 auf die Windenergie und der Rest zu gleichen Teilen auf die Wasserkraft und die Photovoltaik.
Die Erschließung der Potentiale seit 1990 wird im Einzelnen dargestellt. Neben der seit langem genutzten Wasserkraft entwickelt sich insbesondere die Windenergie sehr dynamisch. Die Windenergie wird noch 1997 die Wasserkraft als bedeutendste erneuerbare Energie in Sachsen ablösen. Die weitere Nutzung dieser beiden Energiequellen stößt allerdings auf zunehmende ökologische Bedenken bzw. Widerstände.
Der Anteil der erneuerbaren Energiequellen am Elektroenergieverbrauch in Sachsen erreichte 1996 etwa 1,3 %. Bis zum Jahr 2000 erscheint eine Vergrößerung dieses Anteils auf ca. 5 % möglich.
  • Open Access LogoForschungszentrum Rossendorf; FZR-193 August 1997

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Publ.-Id: 989 - Permalink


Pre- and post-scission light charged particle multiplicities in incomplete fusion reactions
Yanez, R.;
Abstract
In this article we present results concerning the extraction of light charged particle multiplicities in incomplete fusion-fission reactions with a moving source fitting procedure. To demonstrate the feasibility and reliability of the procedure we have used simulated events of known multiplicity to construct kinetic energy distributions at different angles that are fitted assuming several pre- and post-scission sources. In particular, we show that it is necessary to include at least two pre-equilibrium sources in order to extract correctly the known pre-equilibrium proton multiplicity. These two sources are characterized by high ernission temperatures, low emission barriers and high velocities, having ~ 70% and ~ 25% of the beam velocity along the beam axis, respectively The former source is naturally dominant at forward angles due to the strong focusing effect of its high velocity, Contrary to normal expectations, however, the slower pre-equilibrium source is present with considerable yield at the most backward angles θ ~ 145° where it is normally assumed only evaporative components are present. The estracted proton multiplicities are well reproduced by the moving source procedure, as well as fitting parameters with physical relevance.
  • Open Access LogoForschungszentrum Rossendorf; FZR-192

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Publ.-Id: 988 - Permalink


Test und Berechnung des passiven Notkondensators
Schaffrath, A.; Hicken, E. F.; Jaegers, H.; Prasser, H.-M.;
The Siemens AG is developing the new innovative boiling water
reactor concept SWR1000. New features are the passive safety
systems (e.g. emergency condensers, building condensers, passive
pressure pulse transmitters).
For the experimental investigation of the emergency condenser
effectiveness, the NOKO test facility has been constructed at
the Forschungszentrum Jülich in cooperation with Siemens. The
facility has an operating pressure of 10 MPa and a maximum power
of 4 MW for steam production. The condenser bundle consists of 8
tubes and is fabricated with the geometry and material as planned
for the SWR. In more than 200 experiments, the emergency condenser
capacity was tested as a function of pressure, water level and
concentration of noncondensables in the pressure vessel as well as
pressure, water level and temperature in the condenser.
Posttest calculations of NOKO experiments were performed with an
improved version of ATHLET. To calculate the heat transfer coefficients
during condensation in horizontal tubes the module KONWAR has been
developed and implemented in ATHLET. KONWAR is based on the flow regime
map of Tandon and includes several semiempirical correlations for the
determination of the heat transfer coefficients. The presented comparison
between calculations and experiments shows a good agreement
  • Atomwirtschaft-Atomtechnik 42 (1997), Nr. 11, S. 697-700

Publ.-Id: 986 - Permalink


Analysis and Calculation of an Accident with Delayed Scram on NPP Greifswald Using the Coupled Code DYN3D/ATHLET
Kliem, S.;
Analysis and calculation of an abnormal event which occurred in 1989 at the NPP Greifswald (VVER-440/213) are reported about. This event was a scram failure at about 50% nominal power with two of six working main coolant pumps (MCP). The analysis revealed remarkable differences between the active and passive loops due to non-homogeneous coolant mixing in the downcomer and lower plenum in the initial state before the accident. An existing input data deck for the coupled code DYN3D/ATHLET was modified to carry out calculations of this accident. On account of the absence of a mixing model considering loops with forward and loops with backward flow at the same time, the six reactor loops were modeled by a 3-fold (passive), a 2-fold (active) and a single (with the MCP to be switched-off at the beginning of the transient) loop. The comparison of the stationary calculation with the reported data shows a good agreement taking into account the mentioned deviations between the loops. Most of the calculated thermohydraulic parameters during the accident are very close to the measured data. Deviations in the loop temperatures can be explained by the differences in the measured stationary data and by the fact of non-homogeneous coolant mixing in the downcomer and the lower plenum. A small, but continuous power increase was observed during the whole time in the calculation while the measured power was remaining nearly constant. The power behaviour was brought into agreement with the measured data by a correction of the moderator temperature coefficient within the accuracy recommendations of the Atomic Energy Research (AER).
The calculation of this accident is an important contribution to the validation of the coupled code DYN3D/ATHLET. It demonstrated problems of the analysis of real abnormal events on NPP`s.
  • Contribution to proceedings
    Proc. 7th Symposium of AER, pp.457-468, KFKI Atomic Energy Research Institute, Budapest (1997)
  • Lecture (Conference)
    7th Symposium of AER

Publ.-Id: 985 - Permalink


Experimentelle Ergebnisse mit der NOKO-Versuchsanlage
Schaffrath, A.; Hicken, E. F.; Jaegers, H.; Prasser, H.-M.;
On the NOKO (emergency condenser) test station constructed at Jülich Research Centre, the operating performance and effectiveness of the emergency condenser of the boiling water reactor 1000 have been determined in well over 200 tests. It has been possible to check that the tests were in close agreement with a modified version of ATHLET
  • VGB-Kraftwerkstechnik 78 (1998), Heft 5, ISSN 0372-5715, S. 90-96

Publ.-Id: 984 - Permalink


SANS Investigations of the Microstructure of VVER-440-Type RPV Steel after Low Temperature Irradiation at 60 grd C
Grosse, M.; Böhmert, J.; Gilles, R.;
  • Poster
    Annuals User's Meeting, Hahn-Meitner-Institut, Berlin, November 1997, Posterbeitrag

Publ.-Id: 983 - Permalink


Perspektiven der Windenergienutzung in den neuen Bundesländern
Rindelhardt, U.;
Der Stand und die Perspektiven der Windenergienutzung in den neuen Bundesländern unterscheidet sich nicht grundsätzlich von der Situation in den alten Ländern. In einigen Fragen (flächendeckende Potentialerhebungen, durchschnittliche WEA-Größe) ist der Stand sogar höher zu bewerten. Die weitere Entwicklung der Windenergienutzung wird bestimmt durch
- die mittelfristig mögliche Senkung der Stromgestehungskosten (Anforderungen an die Standortwahl und Standortnutzung),
- den praktischen Nachweis von Zuverlässigkeit und Lebensdauer der eingesetzten Anlagen,
- den künftigen ordnungspolitischen Rahmen für die Windenergienutzung (Zielkonflikt Liberalisierung der Strommärkte und Reduktion CO2-Ausstoß) sowie
- die politische und soziale Akzeptanz der Windenergienutzung.
Neben Wissenschaftlern und Technikern steht hier auch die Politik vor einer großen Herausforderung.
  • Lecture (Conference)
    Tagungsband "Windenergienutzung im Binnenland", S. 168 -178 Kassel, 8./ 9. Oktober 1997
  • Contribution to proceedings
    Tagungsband "Windenergienutzung im Binnenland", S. 168 -178 Kassel, 8./ 9. Oktober 1997

Publ.-Id: 982 - Permalink


Definition of the Fifth Dynamic AER Benchmark Problem - A Benchmark for Coupled Thermohydraulic/ Three-Dimensional Hexagonal Neutron Kinetic Codes
Kliem, S.;
The fifth dynamic benchmark defined in this paper is the first benchmark for coupled thermohydraulic system/three-dimensional neutron kinetic core models. In this benchmark the interaction between the components of a VVER-440 NPP with the reactor core should be investigated.

The initiating event is a symmetrical break of the main steam header (MSH) at the end of the first fuel cycle and hot shutdown conditions with one stuck out control rod group. The main purpose is the investigation of recriticality. For this reason, the calculation should be continued until the power excursion is eventually terminated by high-borated water from the high pressure injection system.

The participants of the benchmark should use own input data decks developed according to the needs of their own codes. The main geometrical parameters and characteristics of control and safety systems to be considered in this benchmark will be given to bring into agreement the data decks. Own best estimate nuclear cross section data should be used in the calculation. Only the initial subcriticality at the beginning of the transient will be given to made the results more comparable.
  • Contribution to proceedings
    Proc. 7th Symposium of AER, pp.429-438 , KFKI Atomic Energy Research Institute, Budapest (1997)
  • Lecture (Conference)
    7th Symposium of AER

Publ.-Id: 981 - Permalink


EXAFS Investigations of the Interaction of Humic Acids and Model Compounds with Uranyl Cations in Solid Complexes
Denecke, M. A.; Reich, T.; Pompe, S.; Bubner, M.; Heise, K.-H.; Nitsche, H.; Allen, P. G.; Bucher, J. J.; Edelstein, N. M.; Shuh, D. K.; Czerwinski, K.;
  • Poster
    Migration '97 Konferenz, 26.-31. Oktober, Sendai, Japan
  • Radiochim. Acta 82, 103 (1998)

Publ.-Id: 980 - Permalink


Bremsstrahlung in intermediate-energy nucleon reactions within an effective one-beson exchange model
Shklyar, V.; Kämpfer, B.; Reznik, B. L.; Titov, A. I.;
Abstract
Within a covariant effective one-boson exchange model for the T matrix of NN interactions we present detailed calculations of bremsstrahlung cross sections for proton - proton and proton - neutron reactions at beam energies in the 1 GeV region. Besides pure bremsstrahlung processes we consider photons from ∆ decays and contributions from the η → γγ process. At beam energies above 700 MeV the ∆ decay channel dominates the spectra at large photon energies, where the interference between non-resonance processes and the ∆ decay channel becomes also important. Low energy photons stem from pure bremsstrahlung processes. The available experimental data at 730 MeV beam energy is well described. We extrapolate the model down to 280 MeV, where more detailed experimental data exist, and find agreement with angular distributions.
  • Open Access LogoForschungszentrum Rossendorf; FZR-191
  • Nuclear Physics A 628 (1998) 255-274

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Publ.-Id: 979 - Permalink


Precipitation Studies in Oxygen- and Nitrogen Rich Silicon Formed by High Dose Implantation
Weber, R.; Müller, R.; Skorupa, W.;
  • Other report
    E-MRS 1993 Spring Meeting, Strasbourg, May 4-7, 1993

Publ.-Id: 978 - Permalink


CdS Nanocrystals Entrapped in Thin SiO2 Films
Pham, M. T.; Matz, W.; Möller, D.; Mücklich, A.; Oswald, S.;
  • Journal of Physical Chemistry B Vol. 102, Number 21, Pages 4081-4088, 1998

Publ.-Id: 977 - Permalink


Correlation Between the Powder Structure and Microstructure of Tetragonal ZrO2 Ceramics
Haase, I.; Müller, R.;
  • Poster
    European Ceramic Society, Third Conference, Madrid, September 12-17, 1993, P04-05 (Poster)

Publ.-Id: 976 - Permalink


Untersuchung der Wechselwirkungen zwischen ZrNb1 und austenitischem Stahl bei hohen Temperaturen
Müller, R.; Gleisberg, O.;
  • Poster
    29. Kolloquium des Arbeitskreises für Elektronenmikroskopische Direktabbildung und Analyse von Oberflächen (EDO) 8.-11. Oktober 1996 in Münster
  • Elektronenmikroskop. Direktabb. und Analyse v. Oberfl., 29 (1996)

Publ.-Id: 975 - Permalink


Laserspektroskopie zur Bestimmung der chemischen Speziation von Uranylkomplexen
Bernhard, G.; Geipel, G.; Brendler, V.; Nitsche, H.;
  • Poster
    Poster bei der Hauptjahrestagung der GDCh, Wien, Sept. 1997

Publ.-Id: 974 - Permalink


In-situ Laser Reflectometry Study of the Amorphization of Silicon Carbide by MeV Ion Implantation
Henkel, T.; Heera, V.; Kögler, R.; Skorupa, W.;
  • Journal of Applied Physics,Vol 84, No. 6, Seite 3090-3097

Publ.-Id: 972 - Permalink


Institute of Safety Research; Annual Report 1996
Weiß, F.-P.; Rindelhardt, U.; (Editors)
The report gives an overview on the scientific work of the Institute of Safety Research in 1996.
  • Open Access LogoForschungszentrum Rossendorf; FZR-190 August 1997

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Publ.-Id: 971 - Permalink


Estimats of Dilepton Spectra from Open Charm and Bottom Decays in Relativistic Heavy-Ion Collisions
Kämpfer, B.; Pavlenko, O. P.;
Abstract
The spectra of lepton pairs from correlated open charm and bottom decays in ultrarelativistic heavy-ion collisions are calculated. Our approach includes energy loss effects of the fast heavy quarks in deconfined matter which are determined by temperature and density of the expanding parton medium. We find a strong suppression of the initial transverse momentum spectrum of heavy quarks due to the energy lass at LHC conditions. Within the central rapidity covered by the ALICE detector system, the dominant contribution from bottom decays to the high invariant mass dielectron spectrum is predicted.
  • Open Access LogoForschungszentrum Rossendorf; FZR-188

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Publ.-Id: 970 - Permalink


Thermal Open Charm Signals Versus Hard Initial Yields in ultrarelativistic Heavy-Ion Collisions
Kämpfer, B.; Pavlenko, O. P.; Peshier, A.; Hentschel, M.; Soff, G.;
Abstract.

Exploiting a unique set of parton distribution functions we estimate hard processes for open charm, dilepton and mini-jet production. Assuming rapid thermalization within the mini-jet plasma we follow the evolution (expansion and chemical equilibration) of the parton matter and calculate the energy loss of charm quarks in this environment. A substantial part of charm is espected to thermalize. We try to estimate the thermalized open charm component in the final hadron spectra.
  • Journal of Physics G: Nucl. Part. Phys. 23 (1997) 2001-2011
  • Open Access LogoForschungszentrum Rossendorf; FZR-189

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Publ.-Id: 969 - Permalink


Investigation of Oxidation Resistance of Carbon Based First-Wall Liner Material Aerolor AO5
Krüssenberg, A.-K.; Moormann, R.; Hinssen, H.-K.; Hofmann, M.; Wu, C. H.;
Minimizing the consequences of loss of vacuum and loss of coolant into vacuum accidents with respect to fusion reactor design requires the choice of materials as oxidation resistant as possible. In continuation to the testing of carbon candidate materials under oxidizing conditions (oxygen and steam) in collaboration with NET the carbon compound Aerolor AO5 of Carbone Lorraine has been examined in detail in the test facilities INDEX 2 and SPALEX at Forschungszentrum Jülich. The parameters for these oxidation experiments in the in-pore diffusion controlled regime are temperature (from 973 K up to 1173 K for oxygen, from 1173 K up to 1423 K for steam) and reaction gas concentration (1 vol.-% - 20 vol.% oxygen in argon, 5 vol.% - 100 vol.% steam in argon). The deducted equations for the primary oxidation reactions consider the dependence of the reaction rate on temperature, partial pressure and burn-off of the material.
  • Journal of Nuclear Materials 258-263 (1998) 770-776
  • Poster
    Posterbeitrag während 8th International Conference Fusion Reactor Materials, 26.10 - 31.10.1997, Sendai, Japan

Publ.-Id: 968 - Permalink


Studies of Liquid-Gaseous Two-Phase Systems by Positron Emitting Radiotracers
Hensel, F.;

For a more detailed knowledge and understanding of various industrial processes an in-situ visualization is required. Positron Emission Tomography is an imaging technique used in medical research as a tool to study brain and heart diseases, allowing a non-invasive in-vivo concentration measurement of labeled substances. The mentioned features got us to carry out feasibility investigations for PET-like radiotracer applications in the field of two-phase flow systems. The main aim was to observe mixing and flow phenomena in efficient spatial and time resolution.

Typical values for the stopping ranges of positrons produced by common PET isotopes in water are approximately 2mm. Typical densities of the liquid-gaseous two phase systems that were to investigate are below 10% of the density of water under normal conditions. So the positron range effect becomes very important. Therefore as a first step the spatial annihilation distribution of a solid positron source has been measured using a Ti-45 source and solid blocks of polystyrene and polyurethane foam. The experiments have been carried out using a double head spherical PET-scanner for treatment plan verification of 3D conformable radiation therapy [1]. The foam density amounted from 15 kg/m3 to 38 kg/m3. The feasibility of a range based density measuring technique using the positron range was successfully shown. The next steps in this field could be the setup of a density measurement system for foams, including a detector optimization that results in an easy to handle low cost experimental assembly. It should comprise an encapsulated positron source and 2-4 pairs of detectors to cover an enlarged density range.

Liquid positron emitting tracers were used for monitoring phenomena in bubbly flows. PET experiments often require high activities and quite long integration times for an image reconstruction. Due to activity limitations it has been tried to optimize the experimental setup. Good results were achieved using a nearly two-dimensional geometry in combination with a midplane backprojection. In the experiments mixing processes in bubbly flows were observed using a F-18 solution. The bubbly flows were created by air injection. The event data were collected in list mode. The time resolution for these experiments was below 1s (integration time for the data evaluation). Best choice was a time step value of 500ms. In a further experiment the drainage of a surfactant stabilized foam was investigated.

Transport processes in bubbly flows and foams seem to be adequate topics for investigation using a PET technique. Time resolutions of about 1 s and below can be achieved, depending on the problem. The main advantage of PET tracers is the fact that many organic substances can be labeled with positron emitting isotopes which is important for the component sensitive investigation of many industrial processes.

  • Contribution to proceedings
    3rd Topical Meeting on Industrial Radiation and Radioisotope Measurements and Applications, Conference Program and Abstracts, Raleigh, NC (USA), October 6-9, 1996, p. 101, ISBN 0-89448-645-2
  • Applied Radiation and Isotopes 48 (1997), 1485 - 1492
  • Lecture (Conference)
    3rd Topical Meeting on Industrial Radiation and Radioisotope Measurements and Applications, Raleigh, NC (USA), October 6-9, 1996

Publ.-Id: 967 - Permalink


A numerical three-dimensional stability analysis of the MHD cylinder wake flow
Shatrov, V.; Mutschke, G.; Gerbeth, G.;
  • Lecture (Conference)
    3rd Int. Conference Transfer Phenomena in Magnetohydrodynamic and Electroconducting Flows; September 22-26, 1997 (Assois, France), Vol. 2, pp. 323 - 328
  • Contribution to proceedings
    3rd Int. Conference Transfer Phenomena in Magnetohydrodynamic and Electroconducting Flows; September 22-26, 1997 (Assois, France), Vol. 2, pp. 323 - 328

Publ.-Id: 965 - Permalink


Investigation of the Atomic Interdiffusion and Phase Formation in Ion Beam Irradiated Thin Cu-Al and Ag-Al Multilayers by In-situ RBS and XRD
Markwitz, A.; Matz, W.; Waldschmidt, U.; Demortier, G.;
  • Surface and Interface Analysis, Vol. 26, 160-174 (1998)

Publ.-Id: 964 - Permalink


Test and Calculation of the Emergency Condenser of the SWR 1000
Schaffrath, A.; Prasser, H.-M.; Hicken, E. F.; Jaegers, H.;
The Siemens AG is developing the new innovative boiling water reactor
concept SWR1000. New features are the passive safety systems (e.g.
emergency condensers, building condensers, passive pressure pulse
transmitters, gravitydriven core flooding lines).

For the experimental investigation of the emergency condenser effectiveness,
the NOKO test facility has been constructed at the Forschungszentrum Jülich
in cooperation with Siemens. This test facility has an operating pressure of
10 MPa and a maximum power of 4 MW for steam production. The emergency
condenser bundle consists of eight tubes and is fabricated with planned
geometry and material of the SWR1000. In more than 200 experiments, the
emergency condenser capacity was tested as a function of pressure, water
level and concentration of noncondensables in the pressure vessel as well
of pressure, water level and temperature in the condenser.

Post test calculations of NOKO experiments were performed with an improved
version of ATHLET. To calculate the heat transfer coefficients during
condensation in horizontal tubes the module KONWAR has been developed
and implemented in ATHLET. KONWAR is based on the flow regime map of
Tandon and includes several semiempirical correlations for the determination
of the heat transfer coefficients. The comparison between calculations and
experiments shows a good agreement.
  • Lecture (Conference)
    Post-SMIRT 14 International Seminar "Passive Safety Features in Nuclear Installations", S B2.27-B2.35, 25.-27. August 1997, Pisa, Italien
  • Contribution to proceedings
    Post-SMIRT 14 International Seminar "Passive Safety Features in Nuclear Installations", S B2.27-B2.35, 25.-27. August 1997, Pisa, Italien

Publ.-Id: 963 - Permalink


Non-destructive Evaluation of Glass Corrosion States
Mäder, M.; Grambole, D.; Herrmann, F.; Neelmeijer, C.; Schreiner, M.; Woisetschläger, G.;
  • Nuclear Instruments and Methods in Physics Research B, 136-138 (1998) 863-868
  • Lecture (Conference)
    13th Int. Conf. on Ion Beam Analysis (IBA-13), Lisboa, Portugal, July 27-Aug. 1, 1997

Publ.-Id: 962 - Permalink


Modelling of boron nitride: atomic scale simulations on thin film growth
Albe, K.; Möller, W.;
Molecular-dynamics simulations on ion-beam deposition
of boron nitride are presented. A realistic Tersoff-like potential energy
function for boron nitride, which was specially fitted to ab initio-data,
has been used. The impact of energetic boron and nitrogen atoms on a c-BN
target is simulated with energies ranging from 10 to 600 eV. The structural
analysis of the grown films shows, that a loose, dominantly sp2-bonded
structure arises at high ion flux. In no case the formation of a sp3-bonded
phase is observed, but the obtained films partially reveal textured basal
planes as found in experiment. Two different growth regimes are identified
for ion energies above and below 100 eV.
  • Computational Materials Science 10 (1998) 111
  • Invited lecture (Conferences)
    E-MRS Spring Meeting, Symp. D: Computational Modeling of Issues in Materials Science, Strasbourg, France, June 16 - 20, 1997 (invited lecture)

Publ.-Id: 961 - Permalink


Preparation of SiO2 Films with embedded Si Nanocrystals by Reactive RF-Magnetron Sputtering
Seifarth, H.; Grötzschel, R.; Markwitz, A.; Matz, W.; Nitzsche, P.; Rebohle, L.;
  • Thin Solid Films 330 (1998) 202-205

Publ.-Id: 960 - Permalink


Increased Tool Cutling Life of Drills by Ion Implantation
Hilke, R.; Mändl, S.;
  • Other report
    8th International DAAAM Symposium: Intelligent Manufacturing & Automation, Dubrovnik, Croatia, Oct. 28-25, 1997

Publ.-Id: 959 - Permalink


Strömungsformen bei Kondensationsvorgängen im Notkondensator-Versuchsstand
Prasser, H.-M.; Böttger, A.; Schaffrath, A.;
Im Rahmen des Forschungsvorhabens "Berechnung des passiven Notkondensators eines mit Naturumlauf arbeitenden innovativen Siedewasserreaktors (SWR600) mit ATHLET", das eng mit dem Forschungsvorhaben 15 NU 9050 "Notkondensator für einen Siedewasserreaktor mittlerer Leitung - Versuche zur Ermittlung der Leistung" verknüpft ist, wurden seitens des Forschungszentrums Rossendorf (FZR) e.V. im Rahmen eines F&E-Vertrages Auswertungen und Interpretationen von Messungen zu Strömungsformen und Kondensationsvorgängen im NOKO-Versuchsstand durchgeführt. Neben den Bündelversuchen wurden im NOKO-Versuchsstand mehrere Experimente im einem separaten, seitlich vom Bündel angeordneten und umfangreich instrumentierten Einzelrohr durchgeführt, um die Aussagesicherheit der Notkondensatorexperimente zu erhöhen und zusätzlich experimentelle Daten für die Validierung von Thermohydraulikprogrammsystemen (u.a. den ATHLET-Code) bereitzustellen. Hierbei geht es speziell um die Untersuchung der transienten Zweiphasenströmung innerhalb der Notkondensatorrohre hinsichtlich der dort anzutreffenden Strömungsformen, sowie die Bestimmung des volumentrischen Gasgehaltes an verschiedenen Stellen auf der Sekundärseite im Bündel bei unterkühltem und gesättigtem Sieden. Das NOKO-Einzelrohr wurde hierzu mit nadelförmigen Voidsonden ausgestattet. Durch die Nutzung von jeweils mehreren Sonden in zwei ausgewählten Strömungsquerschnitten wurde die Phasenverteilung während der Füllstandsabsenkung, d.h. beim Durchgang des Flüssigkeitsspiegels an den Sondenpositionen, in-stationär gemessen. Daraus läßt sich die Form der Phasengrenzfläche rekonstruieren. Neben den Messungen im Einzelrohr fanden, ebenfalls mit Nadelsonden, Messungen auf der Sekundärseite des NOKO-Bündels statt. Die Einzelrohr-Versuche an der NOKO-Anlage in Jülich haben gezeigt daß bei entsprechend geringer Konzentration von nichtkondensierbaren Gasen Schwälle und Pfropfen im Ansatz zu beobachten sind, die Vorhersagen bekannter Strömungskarten jedoch nicht zutreffen. Dort werden Schwälle und Pfropfen in wesentlich größerem Aumaß vorhergesagt. Die Aufstellung und Validierung eines einfachen Modells zur Berechnung des Druckverlustes im Wärmeübertragerrohr ist gelungen. Damit kann der Differenzdruck zwischen den Kollektoren ober besser ein an den Wärmeübertragerrohren direkt gemessener Differenzdruck zur Füllstandsmessung auf der Primärseite des Notkondensators herangezogen werden. Bei der Validierung mußten jedoch die experimentell ermittelten Volumina des nichtkondensierbaren Gases in die Berechnung einfließen. Der Mechanismus der Kondensationsbehinderung durch das nichtkondensierbare Gas wurde durch Gegenüberstellung der Sondendaten mit den Meßwerten der Thermoelemente im Einzelrohr im Detail untersucht.
  • Open Access LogoWissenschaftlich-Technische Berichte / Forschungszentrum Rossendorf; FZR-186 Juli 1997

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Publ.-Id: 958 - Permalink


Analysis of deuterium induced nuclear reactions giving criteria for the formation process of expanded austenite
Parascandola, S.; Günzel, R.; Grötzschel, R.; Richter, E.; Möller, W.;
High current ion nitriding of austenitic stainless steel at temperatures of about 400°C leads to the formation of a surface layer, called expanded austenite. The formation of this layer is not well understood. Deuterium induced nuclear reaction analyses have been performed on austenitic stainless steel samples that were subsequently high current ion nitrided with low energy ion implantation of 15 N and 14 N. The obtained depth profiles yield criteria for the formation process of the expanded austenite. A trapping mechanism cannot be confirmed.
  • Nuclear Instruments and Methods in Physics Research B, 136-138 (1998) 1281
  • Poster und Beitrag zu Sammelwerken / Proceedings of the Thirteenth International Conference on Ion Beam Analysis, Lisbon, Portugal, 27 July - 1 August 1997

Publ.-Id: 956 - Permalink


Comment on "On the Relation Between Unimolekular Reaction Rates and Overlapping Resonances"
Rotter, I.;
  • J. Chem. Phys. 106(11), 4810, 15 March 1997

Publ.-Id: 955 - Permalink


Initial Inter-Laboratory Testing of the Rossendorf-Oxford (ROX97) Secondary Standard for X-ray Analysis
Neelmeijer, C.; Mäder, M.; Jarjis, R.; Calligaro, T.; Salomon, J.; Schreiner, M.; Gantz, T.;
  • Nuclear Instruments and Methods in Physics Research B, 136-138 (1998) 902-907
  • Lecture (Conference)
    13. Int. Conf. on Ion Beam Analysis (IBA-13), Lisboa, Portugal, July 27 - Aug. 1, 1997

Publ.-Id: 954 - Permalink


Estimates of Dilepton Spectra from Open Charm and Bottom Decays in Relativistic Heavy-Ions Collisions
Kämpfer, B.; Pavlenko, O. P.; Gallmeister, K.;
  • Physics Letters B 419 (1998) 412-418

Publ.-Id: 953 - Permalink


Determination of Structural Parameters of Uranyl Ion Complexed with Organic Acids Using EXAFS
Denecke, M. A.; Reich, T.; Bubner, M.; Heise, K.-H.; Nitsche, H.; Allen, P. G.; Bucher, J. J.; Edelstein, N. M.; Shuh, D. K.;
  • Contribution to external collection
    Actinides '97 Conf.
  • J. Alloys and Compounds 271-273, 123 (1998)

Publ.-Id: 952 - Permalink


Synthetische Huminsäuren für die Umweltforschung
Heise, K.-H.; Pompe, S.; Bubner, M.; Nitsche, H.;
  • Lecture (Conference)
    Arbeitstagung der Deutschen Gesellschaft für Moor- und Torfkunde e. V., Bad Elster, Germany, 04.-05.09. 1997

Publ.-Id: 951 - Permalink


LOWRAD 96; Methods and Applications of Low-Level Radioactivity Measurements; Proceedings of a Workshop Rossendorf/Dresden, 7-8 November 1996
Nitsche, H.; Niese, S.;
  • Open Access LogoForschungszentrum Rossendorf; FZR-170

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Publ.-Id: 948 - Permalink


Nuclear and Hadron Physics and Project ELBE; Annual Report 1996
Barz, H.-W.; Dönau, F.; Enghardt, W.; Grosse, E.; Kämpfer, B.; Prade, H.; Schlett, M.; Wünsch, R.;
  • Open Access LogoForschungszentrum Rossendorf; FZR-179 April 1997

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Publ.-Id: 947 - Permalink


The Chiral Quark-Loop Soliton in a Hot Gas of Constituent Quarks
Schleif, M.; Wünsch, R.;
Abstract
We consider a chiral one-loop hedgehog soliton of the bosonized SU(2)f Nambu & Jona-Lasinio model which is embedded in a liot medium of constituent quarks. Energy and radius of the soliton are determined in self-consistent mean-field approximation. Quasi-classical corrections to the soliton energy are derived by means of the pushing and cranking approaches. The corresponding inertial parameters are evaluated. It is shown that the inertial mass is equivalent to the total internal energy of the soliton. Corrected nucleon and ∆ isobar masses are calculated in dependence on temperature and density of the medium. As a result of the internal structure of the soliton which is controlled by the self-consistent mean field, the scaling between constituent quark mass and soliton mass is noticeable disturbed.
  • Open Access LogoForschungszentrum Rossendorf; FZR-182

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Publ.-Id: 946 - Permalink


Ionendriftprozesse in Borsilikatgläsern während des anodischen Bondens
Nitzsche, P.; Lange, K.; Schmidt, B.; Grigull, S.; Kreißig, U.; Huber, H.; Assmann, W.; Thomas, B.; Herzog, K.;
  • Open Access LogoForschungszentrum Rossendorf; FZR-184 Juli 1997

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Publ.-Id: 944 - Permalink


N.C.A.11C-Labelling of Benzenoid Compounds in Ring Positions: [11C]Anisole Derivatives
Mäding, P.; Steinbach, J.; Johannsen, B.;
The synthesis route to n.c.a. 3-nitro-[3-C-11]anisole (3) by use of the principle of synchronous six-electron cyclization of hexatriene systems into aromatics is described and discussed. Nitro-[C-11]-methane (1) reacts with the prepared precursor 5-dimethylamino-2-methoxy-penta-2,4-dienylidene-1-dimethylammonium tetrafluoroborate (2b) in the presence of BuLi to form 1-dimethylamino-4-methoxy-6-nitro-[6-C-11]hexatriene (IA, IB), followed by cyclization/ aromatization into 3. Starting from 1, 3-nitro-[3-C-11]anisole of a radiochemical purity of about 65 % and a mean specific radioactivity of 1 Ci/mu mol was obtained within 10 min. Related to [C-11]CH3NO2, the reproducible radiochemical yield of 3 (decay-corrected) was 60+/-5 %. Reduction of 3 by heating the above reaction mixture with aqueous Na2S gave 3-amino-[3-C-11]anisole (4) of a radiochemical purity of about 50 %. The reproducible radiochemical yield of 4 (decay-corrected) in relation to 1 was 45+/-5 %, the synthesis time from 1 was 16 min.
  • Journal of Labelled Compounds and Radiopharmaceuticals 39 (7): 585-599 JUL 1997

Publ.-Id: 942 - Permalink


Sheath and Presheath Dynamics in Plasma Immersion Ion Implantation
Mändl, S.; Günzel, R.; Möller, W.;
  • Journal of Physics D: Applied Physics 31 (1998) 1109-1117

Publ.-Id: 940 - Permalink


Helium Bubbles in Silicon: Study of the Residual Helium Content using Elastic Recoil Detection Analysis
Kaschny, J. R.; Fichtner, P. F. P.; Mücklich, A.; Kreißig, U.; Yankov, R. A.; Skorupa, W.;
  • Lecture (Conference)
    13th Int. Conf. on Ion Beam Analysis (IBA-13), Lissabon, Portugal, July 27 - Aug 1, 1997
  • Contribution to external collection
    Nucl. Instr. Meth. B136-138 (1998) 583

Publ.-Id: 939 - Permalink


Identification and Discrimination of Thiobacilli Using ARDREA, RAPD and Rep-APD
Selenska-Pobell, S.; Otto, A.; Kutschke, S.;
  • Journal of Applied Bacteriology, 84, (1998), p. 1085-1091
  • Poster
    15. DECHEMA-Jahrestagung der Biotechnologen, Münster, 04.-06.03.1997

Publ.-Id: 938 - Permalink


In Situ ERDA Studies of Ion Drift Processes
Kreißig, U.; Grigull, S.; Lange, K.; Nitzsche, P.; Schmidt, B.;
  • Nuclear Instruments and Methods in Physics Research B ( IBA '97)

Publ.-Id: 937 - Permalink


Angle dependent Mössbauer Spectroscopy
Reuther, H.; Behr, G.;
  • Contribution to external collection
    Hyperfine Interactions ( ICAME '97 Conf. Proc.)

Publ.-Id: 936 - Permalink


Alloying by High Dose Ion Implantation of Iron into Magnesium and Aluminium
Reuther, H.; Betzl, M.; Matz, W.; Richter, E.;
  • Hyperfine Interactions 113 (1998) 391-401

Publ.-Id: 935 - Permalink


Phase Formation of Iron Silicides by Ion Implantation
Dobler, M.; Reuther, H.; Möller, W.;
  • Hyperfine Interactions (C) 3 (1998) 145-148

Publ.-Id: 934 - Permalink


A Combination of Atomic and Continuum Models Describing the Evolution of Nanoclusters
Strobel, M.; Heinig, K.-H.; Möller, W.;
  • Computational Materials Science 10 (1998) 457-462

Publ.-Id: 933 - Permalink


Molecular-Dynamics Studies of a C:H Film Growth by Energetic Hydrocarbon Molecule Impact
Jäger, H.-U.; Weiler, W.;
  • Diamond and Related Materials 7 (1998) 858-863
  • Lecture (Conference)
    8th European Conference on Diamond, Diamond-Like and Related Materials, Edinburgh, UK, Aug. 3 - 8, 1997

Publ.-Id: 931 - Permalink


Novel Rhenium Complexes Derived from ALPHA-Tropanol as Potential Ligands for the Dopamin Transporter
Hoepping, A.; Brust, P.; Berger, R.; Leibnitz, P.; Spies, H.; Machill, S.; Scheller, D.; Johannsen, B.;
  • Bioorganic & Medicinal Chemistry 6 (1998) 1663-1672

Publ.-Id: 930 - Permalink


Thermodynamic properties of the SU(2)f chiral quark-loop soliton
Schleif, M.; Wünsch, R.;
  • European Physical Journal A 1, 171-186 (1998)

Publ.-Id: 929 - Permalink


Comment on Amorphization and Defect Recombination in Ion Implanted Silicon Carbide
Heera, V.;
  • Journal of Applied Physics Vol 83, Number 7, pp 3935-3936

Publ.-Id: 928 - Permalink


Microstructure and Tribological Properties of Aluminium Implanted with High Doses of Nickel
Wieser, E.; Grötzschel, R.; Mücklich, A.; Prokert, F.;
  • Nuclear Instruments and Methods in Physics Research B 134 (1998) 365-376

Publ.-Id: 927 - Permalink


A Simple Paper-based Secondary Standard for Energy Dispersive X-Ray Analysis
Neelmeijer, C.; Hüller, J.; Mäder, M.; Borchers, B.; Jarjis, R.;
  • Nuclear Instruments and Methods in Physics Research B 140 (1998) 191-198

Publ.-Id: 926 - Permalink


Nitriding of Austenitic Stainless Steel Using Plasma Immersion Ion Implantation
Mändl, S.; Günzel, R.; Richter, E.; Möller, W.;
  • Surface & Coatings Technology 100-101 (1998) 372-376

Publ.-Id: 924 - Permalink


Wave mixing at the Hg-HgO interface
Kolevzon, V.; Pozdniakov, G.;
  • Other report
    1997 Fall MRS Meeting, Boston December 2-6

Publ.-Id: 923 - Permalink


Roughness Improvement and Hardness Enhancement in Nanoscale Al/AlN Multilayered Thin Films
Wang, X.; Kolitsch, A.; Möller, W.;
  • Applied Physics Letters, 71 (14), 6 October 1997, 1951-1953

Publ.-Id: 922 - Permalink


Synthesis of Rhenium(I) and Technetium(I) Carbonyl/Dithioether Ligand Complexes Bearing 3,17-BETA-Estradiol
Reisgys, M.; Wüst, F.; Alberto, R.; Schibli, R.; Schubiger, P. A.; Pietzsch, H.-J.; Spies, H.; Johannsen, B.;
  • Bioorganic and Medicinal Chemistry Letters, Vol. 7, No. 17, pp 2243-2246, 1997

Publ.-Id: 921 - Permalink


HPLC-Analysis of the Metabolism of 6-[18F]-Fluoro-L-DOPA (FDOPA) in the Brain of Neonatal Pigs
Vorwieger, G.; Brust, P.; Bergmann, R.; Bauer, R.; Walter, B.; Füchtner, F.; Steinbach, J.; Johannsen, B.;
  • Book (Authorship)
    Quantitative Functional Brain Imaging with Positron Emission Tomography, Carson, R. E.; Daube-Witherspoon, M. E.; Herscovich, P.; eds); Academic Press, 285-292

Publ.-Id: 920 - Permalink


Recriticality Calculations for Uraniumdioxide-Water Systems with MCNP
Kumpf, H.;
With the aim of generating a certain feeling for the general dependencies of the multiplication factor k the first section provides some results for two classes of deformations of the original fuel pins. The main part examines UO2-structures of increasing disorder, beginning with the hexagonal close package of fuel spheres and ending up with stochastic geometries. Among these structures the worst case, i.e. the one with the highest k but preserving mechanical stability is identified. The composition and geometric parameter of this case is used to calculate the critical thickness of a slab and critical radius of a sphere.
  • Open Access LogoForschungszentrum Rossendorf; FZR-183, June 1997

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Publ.-Id: 919 - Permalink


On-Line Isothermal Gas Chromatography with Short-lived Mo- and Tc-Isotopes in the O2H2O(g)/SiO2(s)-System
Vahle, A.;
  • Lecture (Conference)
    4. Workshop Chemistry and Physics of the Heaviest Elements, 5.-8.6.1997, Göteborg

Publ.-Id: 918 - Permalink


Trace Amount Components in Laminar Gas Flow - Theoretical and Experimental Studies
Grantz, M.;
  • Lecture (Conference)
    4. Workshop Chemistry and Physics of the Heaviest Elements, 5.-8.6.1997, Göteborg

Publ.-Id: 917 - Permalink


Multimodal impurity redistribution and nanocluster formation in Ge implanted silicon dioxide films
von Borany, J.; Grötzschel, R.; Heinig, K.-H.; Markwitz, A.; Matz, W.; Schmidt, B.; Skorupa, W.;
  • Applied Physics Letters 71 (22), 1 December 1997, p. 3215-3217

Publ.-Id: 916 - Permalink


Thermochromatography of No-259
Taut, S.;
  • Lecture (Conference)
    4. Workshop Chemistry and Physics of the Heaviest Elements, 5.-8.6.1997, Göteborg

Publ.-Id: 915 - Permalink


Status of the Preparation for Seaborgium Gas Chemistry Experiments with Oxidehydroxides
Hübener, S.;
  • Lecture (Conference)
    4. Workshop Chemistry and Physics of the Heaviest Elements, 5.-8-6-1997, Göteborg

Publ.-Id: 914 - Permalink


Deposition of tetrahedral hydrogenated amorphous carbon using a novel Elecron Cyclotron Wave Resonance reactor
Weiler, M.; Lang, K.; Li, E.; Robertson, J.;
  • Applied Physics Letters Volume 72, Number 11, pp 1314-1316

Publ.-Id: 911 - Permalink


Direktmessung alpha-aktiver Nuklide - Projektfortschritte
Nebelung, C.; Nitsche, H.; Bernhard, G.;
  • Lecture (Conference)
    GRS Köln, 12.5.97

Publ.-Id: 910 - Permalink


The 4 pi - fragment - spectrometer FOBOS
Ortlepp, H.-G.; Wagner, W.; Herbach, C.-M.; Aleksandrov, A. A.; Aleksandrova, I. A.; Andrassy, M.; Budzanovski, A.; Czech, B.; Danziger, M.; Dietterle, L.; Doronin, V. N.; Dshemuchadse, S.; Fomichev, A. S.; Fromm, W. D.; Gebhardt, M.; Gippner, P.; Heidel, K.; Heinitz, S.; Homeyer, H.; Ivanovsky, S. I.; Kamanin, D. V.; Kolesov, I. V.; Matthies, A.; May, D.; Merzlyakov, S. I.; von Oertzen, W.; Oganessian, Y. T.; Pausch, G.; Penionzhkevich, Y. E.; Pyatkov, Y. V.; Radnev, S. V.; Renz, G.; Rubinskaya, L. A.; Sandrev, I. D.; Schilling, K.-D.; Seidel, W.; Shishkin, D. I.; Sirotin, A. P.; Sodan, H.; Strekalovsky, O. V.; Tishchenko, V. G.; Trofimov, V. V.; Tsurin, I. P.; Umlauf, C.; Vakatov, D. V.; Vasko, V. M.; Vitenko, V. A.; Will, E.; Wilpert, M.; Yanez, R.; Zhuchko, V. E.; Ziem, P.; Zrodlowski, L.;
Abstract
The 4 π - fragment - spectrometer FOBOS developed for heavy-ion research at beam energies of 10 - 100 AMeV has been commissioned for physical experiments at the Flerov Laboratory of Nuclear Reactions of the Joint Institute for Nuclear Research in Dubna. Based on the logarithmic detector principle, it is able to register charged fragments from Protons up to heavy residual nuclei in a large dynamical range. Position-sensitive avalanche counters, axial ionization chambers and CsI(TI) scintillation detectors are arranged in three concentric detector shells. An array of phoswich detectors is used as a more granular forward detector at narrow polar angles. The modular concept of FOBOS allows for different experimental application in the field of exclusive fragment spectroscopy at medium multiplicities. For illustration the fragment spectroscopy studies concerning the spontaneous fission process and the fragmentation of hot nuclei by means of the FOBOS set-up are considered.
  • Nuclear Instruments and Methods in Physics Research A 403 (1998) 65-97
  • Open Access LogoForschungszentrum Rossendorf; FZR-181

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Publ.-Id: 909 - Permalink


Modification of Silicon Nitride Ceramics with High Intensity Pulsed Ion Beams
Brenscheidt, F.; Piekoszewski, J.; Wieser, E.; Langner, J.; Grötzschel, R.; Reuther, H.;
  • Materials Science and Engineering A253 (1998) 86-93
  • Lecture (Conference)
    Modification of Ceramics and Semiconductors by Ion Bombardment, Ciocco, Italy, May 19-23, 1997

Publ.-Id: 907 - Permalink


Institut of Radiochemistry; Annual Report 1996
Nitsche, H.; Bernhard, G.; Engelmann, H.-J.;
  • Open Access LogoForschungszentrum Rossendorf; FZR-180

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Publ.-Id: 906 - Permalink


Ion drift processes in PYREX-type alkali-borosilicate glass during anodic bonding
Nitzsche, P.; Lange, K.; Schmidt, B.; Grigull, S.; Kreißig, U.; Thomas, B.; Herzog, K.;
  • Journal of the Electrochemical Society, Vol. 145, No. 5, May 1998, pp 1755-1762

Publ.-Id: 905 - Permalink


Windenergiepotential in Sachsen
Hirsch, W.; Rindelhardt, U.;
The wind energy ressources of Saxony, a typical interior state of Germany, have been estimated based on a special wind measuring programme. It was performed between 1991 and 1995. The main problem in applying the wind atlas method was to determine the areas with the same wind climate and the corresponding data sets (atlas stations). After defining the atlas stations ressource file calculations were performed over about 60 % of the saxon territory. The technical potential of wind energy in Saxony was estimated to be 5 TWh p.a. First results from saxon WEC`s confirm the results.
  • DEWI-Magazin Nr. 11, August 1997, S. 44 - 49

Publ.-Id: 904 - Permalink


Ermittlung bruchmechanischer Kennwerte im instrumentierten Kerbschlagbiegeversuch - Vergleichsuntersuchungen zur Rißdetektion mit Schallemission und dem Laserstreulichtverfahren
Richter, H.; Böhmert, J.; Valo, M.; Viehrig, H.-W.;
  • Lecture (Conference)
    Deutscher Verband für Materialforschung und -prüfung, Tagung Werkstoffprüfung 1997, Dezember 1997, Bad Nauheim, Vortragsband, S. 217 ff.
  • Contribution to proceedings
    Deutscher Verband für Materialforschung und -prüfung, Tagung Werkstoffprüfung 1997, Dezember 1997, Bad Nauheim, Vortragsband, S. 217 ff.

Publ.-Id: 903 - Permalink


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