Practical trainings, student assistants and theses

Optimization of fitting procedures in surface complexation models (Id 416)

Student practical training / Student Assistant / Volunteer internship

Production of electricity by nuclear power plants inevitably generates high-level and long-lived radioactive waste. A solution considered by several nuclear waste management agencies is to store them into deep underground repositories. The principle of such a concept is to provide a multi-barrier system to avoid the release of the radioactive waste through the biosphere for very long time scales (up to hundred thousand of years). It is thus of great importance to be able to characterize both at a macroscopic and a molecular level the different processes (retention, reduction, surface precipitation, etc.) that can take place onto mineral surfaces and thus affect the availability and the mobility of the radionuclides. This information can be inserted in surface complexation models for the description and prediction over a long time-scale of the interaction of pollutants at the solid/liquid interface with several sorbent surfaces. These surface complexation models rely on a thermodynamic description of the solid/water interface and represent a geochemically robust and sound approach to quantify adsorption equilibria.

The solution of adsorption equilibria problems can be reached via Gibbs Free Energy Minimization and/or Law of Mass Action. Standard procedures apply commonly used geochemical software such as FITEQL/PHREEQC coupled to shell optimizers (UCODE, PEST). They are nevertheless subject to numerical instability and/or convergence problems, and to the risk to fall into a local minimum region rather than a global optimum valley. This risk is drastically increased when the number of adjustable parameters becomes higher than 3 or 4. Also the “trial and error” approach within the numerical fitting data can become very fast time consuming.

Thus, the objective of the present work are i) to develop alternative approaches to enable the handling of a high number of adjustable parameters at once, ii) the speed up of the optimizing procedure in order to reduce the time required for the user to reach a satisfactory description of the experimental data.

Your specific tasks:

  • Implement a genetic algorithm coupled to Levenberg-Marquardt optimization on a high performance computing cluster,
  • Compare the results of with another optimization path, namely Downhill Simplex,
  • Find reliable ways to provide realistic uncertainties of the adjustable parameters (e.g. scale sensitivity, Monte-Carlo, etc.).

This internship or assistant position can be used as a basis for a follow-up Research Project, Bachelor or Master thesis.

Department: Surface Processes

Contact: Dr. Jordan, Norbert, Dr. Kelling, Jeffrey

Requirements

Good knowledge in python programming and standard optimization routines (Newton-Raphson, Levenberg-Marquardt, etc.) is mandatory.

Students without knowledge in chemistry are also encouraged to apply.

Very good English skills are appreciated.

Conditions

Duration min. 3 months

Start: from now

Workplace: HZDR, Dresden-Rossendorf

Online application

Please apply online: english / german

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Investigation of thin film oxide layers by ion beam sputtering in nanoelectronics (Id 415)

Bachelor theses / Master theses / Diploma theses

**Tasks:**
1. Development of thin film oxides using Ion Beam Sputtering for nanoelectronic applications
2. Optimization of process parameters for the controlled fabrication of thin oxide layers
3. Characterization of the synthesized thin oxide films
4. Evaluation of the electronic, structural, and mechanical properties of the fabricated oxide films
5. Application of thin film oxides in specific nanoelectronic devices and performance comparison
with conventional materials

Department: Nanomaterials and Transport

Contact: Zscharschuch, Jens, Dr. Garcia Valenzuela, Aurelio

Requirements

**Requirements:**
1. Enrolment in a master's program in materials science, chemistry, physics, or a related field
2. Interest in thin film coating and nanoelectronics
3. Basic knowledge in the fabrication and characterization of thin films
4. Experimental skills in laboratory techniques
5. Independent work ethic and teamwork capabilities

Conditions

**We offer:**
1. An innovative research environment with access to state-of-the-art technology and laboratory
facilities.
2. Supervision by experienced scientists.
3. Opportunities to participate in conferences.
4. Practical experience in the field of thin film coating and nanoelectronics.

The master's thesis has a duration of six months. Extension or adjustment of the duration can be
discussed with the supervisor.

Interested students are requested to submit their application documents, including a resume,
university transcript and a motivation letter.

Online application

Please apply online: english / german

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Structuring 2D materials via nanolithography (NanoFrazor) (Id 414)

Bachelor theses / Master theses / Diploma theses

**Tasks:**
1. Investigate nanolithography techniques using the Nanofrazor for the structuring of 2D materials
2. Optimize process parameters for precise control of size and shape of generated nanostructures
3. Characterize the modified 2D materials
4. Evaluate the manufactured nanostructures
5. Compare the performance of different nanolithography approaches and identify optimization
opportunities

Department: Nanomaterials and Transport

Contact: Zscharschuch, Jens

Requirements

**Requirements:**
1. Enrolment in a master's program in materials science, chemistry, physics, or a related field
2. Interest in nanotechnology and nanolithography
3. Basic knowledge in the fabrication and characterization of 2D materials
4. Experimental skills in working with laboratory techniques
5. Independent work ethic and teamwork capabilities

Conditions

**We offer:**
1. An innovative research environment with state-of-the-art laboratory equipment.
2. Supervision by experienced scientists.
3. Opportunities to participate in conferences.
4. Practical experience in the field of nanotechnology and materials science.

The master's thesis has a duration of six months. Extension or adjustment of the duration can be
discussed with the supervisor.

Interested students are requested to submit their application documents, including a resume,
university transcript and a motivation letter.

Online application

Please apply online: english / german

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2D Material Exfoliation Optimisation (Id 413)

Bachelor theses / Master theses / Diploma theses

**Tasks:**
1. Investigate various exfoliation methods for 2D material fabrication
2. Optimize exfoliation processes to achieve high-quality, thin layers
3. Characterize the synthesized 2D materials using advanced analysis methods
4. Evaluate the electronic, optical, and mechanical properties of the exfoliated 2D materials
5. Compare the performance of different exfoliation approaches and identify optimization
opportunities

Department: Nanomaterials and Transport

Contact: Zscharschuch, Jens

Requirements

**Requirements:**
1. Enrolment in a master's program in materials science, chemistry, physics, or a related field
2. Interest in nanomaterial science
3. Basic knowledge in the synthesis and characterization of materials
4. Experimental skills in handling laboratory equipment
5. Independent work mentality and ability to work in a team

Conditions

**We offer:**
1. An innovative research environment with state-of-the-art laboratory equipment.
2. Supervision by experienced scientists.
3. Opportunities to participate in scientific conferences.
4. Practical experience in the field of materials science.

The master's thesis has a duration of six months. Extension or adjustment of the duration can be
discussed with the supervisor.

Interested students are requested to submit their application documents, including a resume,
university transcript and a motivation letter.

Online application

Please apply online: english / german

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Unterstützung im Rechnungswesen (Id 408)

Student Assistant

Die Abteilung Finanzen, Finanzcontrolling und Drittmittel ist für das Finanzmanagement des Helmholtz-Zentrum Dresden-Rossendorf verantwortlich. Im Bereich Rechnungswesen (Haupt-, Banken-, Debitoren-, Kreditoren- und Anlagenbuchhaltung) wird Ihre Hilfe benötigt.

Ihre Aufgaben:

  • Unterstützung (SAP) bei der Erfassung von Geschäftsvorfällen
  • Unterstützung (SAP) bei der Stammdatenpflege, insbesondere Kreditoren
  • Sonstige Unterstützungstätigkeiten

Department: Finance, Financial Controlling and Third-party Funds

Contact: Hartwig, Patrick

Requirements

  • Begonnenes Studium der Wirtschaftswissenschaften
  • Erste Kenntnisse in den Grundlagen des Rechnungswesens (Buchführung, Kosten- und Leistungsrechnung)
  • Selbstständige und verantwortungsvolle Arbeitsweise

Conditions

  • Arbeitsbeginn ab sofort
  • Mindestens 6 Monate
  • Tätigkeitsort: Standort Dresden-Rossendorf

Wir bieten Ihnen die Möglichkeit, im Studium Erlerntes praxisnah umzusetzen! Es erwarten Sie ein
motiviertes und kollegiales Arbeitsumfeld, tatkräftige Unterstützung bei der Umsetzung Ihrer Aufgaben sowie spannende Einblicke in die finanztechnische Schaltzentrale unseres Forschungsstandortes.

Online application

Please apply online: english / german

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Student internship, research assistant, school practical training, master/diploma thesis, compulsory internship (Id 407)

School practical training / Student practical training / Bachelor theses / Master theses / Diploma theses / Student Assistant / Holiday job / Compulsory internship / Volunteer internship / Research Assistant

At Helmholtz-Zentrum Dresden-Rossendorf (HZDR), over 1,500 employees from more than 70 nations are conducting cutting-edge research in the fields of ENERGY, HEALTH, and MATERIALS to address the major challenges facing society today.
The Center for Advanced Systems Understanding (CASUS), founded in Görlitz in 2019, is a German-Polish interdisciplinary research center focusing on data-intensive digital systems.
CASUS offers student internships in a wide range of scientific fields. You are welcome to apply and join CASUS if you are interested in gaining knowledge in the following research areas:

  • Theoretical Chemistry
  • Earth System Science
  • Matter under Extreme Conditions
  • Systems Biology
  • Digital Health
  • Computational Radiation Physics
  • Computational Quantum Many-Body Theory
  • Mathematical Foundations of Complex System Science
  • Dynamics of Complex Living Systems
  • Machine Learning for Infection and Disease
You can also apply to join our administrative team as a student assistant.

Institute: CASUS

Contact: Dr. Mir Hosseini, Seyed Hossein, Mazur, Weronika, Dr. Calabrese, Justin, Dr. Martinez Garcia, Ricardo, Dr. Bussmann, Michael, Dr. Cangi, Attila, PD Dr. Kuc, Agnieszka Beata, Dr. Yakimovich, Artur, Dr. Knüpfer, Andreas

Requirements

  • Student in computer science, physics, chemistry, or related fields
  • Student already enrolled at the university in Germany, Poland or Czech Republic (close exchange and attendance in the office preferable and combined with the moblie working from Germany combinable)
  • Eager to learn new skills
  • Strong motivation to work in a collaborative environment
  • Preliminary experience in code development is an advantage
  • Excellent communication skills in English and/or German or Polish

Conditions

  • A vibrant research community in an open, diverse and international work environment
  • Scientific excellence and extensive professional networking opportunities
  • A wide range of qualification opportunities
  • We support a good work-life balance with the possibility of part-time employment, mobile working and flexible working hours
  • Either an immediate start or a start in 2024 is possible
Please submit your application (including a one-page cover letter, CV, academic degrees, transcripts, etc.) online on the HZDR application portal

Online application

Please apply online: english / german

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Competitive bubble-particle attachment from a particle mixture in a model stirred cell (Id 405)

Master theses / Diploma theses / Compulsory internship

Foto: Particles on bubble in cell ©Copyright: Dr. Milad Eftekhari Flotation is a widely used technique worldwide to extract valuable minerals from less valuable ones. To make the process more efficient, several methods have been developed to investigate how various factors affect particle floatability (recovery). Traditionally, this is done by measuring the hydrophobicity of the particles. However, floatability is a much broader concept that encompasses not only hydrophobicity but also other factors such as hydrodynamic conditions. In our research, we introduce a novel approach to quantify particle floatability from a mixture through dynamic bubble surface coverage experiments, considering hydrodynamic effects. Our focus is to understand how the different particles attach to a single bubble from a system containing two (or three) different particle types (chalcopyrite and/or pyrite + quartz). In particular, how one type of particle affects the recovery of another type.

Our objective is:

  • To study the effect of pH and collector concentration on particle floatability.
  • To establish a correlation between floatability and flotation recovery.
Experimental methods/techniques:
  • Image acquisition and analysis
  • Particle size analysis techniques such as laser diffraction and dynamic light scattering

Department: Transport processes at interfaces

Contact: Dr. Eftekhari, Milad, Öktem, Gülce

Requirements

  • duration min. 6 month, workplace: HZDR

Online application

Please apply online: english / german

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Dynamics of bubble-particle attachment in a model stirred cell (Id 404)

Master theses / Diploma theses / Compulsory internship

Foto: Dynamics of bubble-particle attachment in a model stirred cell ©Copyright: Dr. Milad EftekhariA process called flotation is widely used throughout the world to separate valuable minerals from non-valuable ones. Successful flotation relies on several sub-processes, such as promoting the attachment of certain sizes of particles to bubbles while preventing the attachment of others. Therefore, it is important to advance our knowledge about the particle attachment process, particularly, when different particle sizes are considered. Here we use our in-house setup to study:

  • The effect of ultrafine particles on the attachment rate of fine particles.
  • The effect of various parameters e.g., particles hydrophobicity on the packing density of the particles.
Experimental methods/techniques:
  • Image analysis
  • Particle size analysis techniques such as laser diffraction and dynamic light scattering

These experimental methods and the topic of particles at interfaces can prepare you for a variety of jobs after graduation, as these concepts are widely applicable in various fields such as mineral processing, recycling, pharmaceuticals, cosmetics, painting, and so on.

Department: Transport processes at interfaces

Contact: Dr. Eftekhari, Milad, Dr. Schwarzenberger, Karin

Requirements

  • Study in process engineering, chemical engineering (or comparative field of study)
  • Motivation, interest in this field of research, experimental experience
  • Optimally: basic knowledge of particle measurement techniques

Conditions

duration min. 6 month, start: from now, workplace: HZDR

Online application

Please apply online: english / german

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Investigation of the flow following behavior of lagrangian sensor particles in aerated reactors (Id 398)

Master theses / Diploma theses / Compulsory internship

Foto: Sensor particle next to stirrer with bubbles ©Copyright: Lukas BuntkielData acquisition in large industrial vessels such as bio reactor, biogas fermenters or wastewater treatment plants is limited to local measurement points due to the limited access to the vessel and the non-transparent fluid. To optimize these kinds of plants the three-dimensional flow field and the spatial distribution of e.g. temperature and electrical conductivity inside the vessel needs to be known. This can be done by the autonomous flow following lagrangian sensor particles (LSP) developed at the HZDR. Equipped with a pressure sensor, an accelerometer, two gyroscopes and a magnetometer, the sensor particle can track the flow movement inside of the vessels. From this, the flow field can be reconstructed.

To achieve a good flow following behavior, the density of the LSP can be adjusted before they are released into the vessel. While this works well for non-aerated systems, the influence of aeration on the flow following capability is unknown. Another unknown is how the velocities of the rising bubbles and of the continuous phase relates to the velocity measured by the LSP.
Therefore, the aim of this master thesis is to investigate the influence of aeration on the LSPs theoretically and experimentally by tracking the LSP with a camera. This includes the following tasks:

  • Literature research on flow following behavior of large particles in fluids
  • Experiments in a bubble column (330 mm ID) with LSPs and camera
  • Data evaluation to retrieve the fluid velocity, bubble rising velocity and LSP velocity
  • Comparison and conclusions on the flow following capability of LSPs in aerated reactors and comparison to the non-aerated case.

Department: Efficient wastewater treatment

Contact: Buntkiel, Lukas, Marchini, Sara

Requirements

  • Studies in the area of chemical or mechanical engineering or similar
  • Basic chemical and fluid engineering knowledge
  • Data analysis in Python
  • Independent and structured way of working

Conditions

  • Immediate start possible
  • Duration according to the respective study regulations

Links:

Online application

Please apply online: english / german

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Numerical investigation of particle mixing - internship or thesis (Id 396)

Master theses / Diploma theses / Compulsory internship / Volunteer internship

Foto: Mixing of Fine Particles ©Copyright: Dr. Stephan BodenFine-grained solid particles from various industrial sources, which would otherwise be discarded, should ideally be processed to valuable products or inert residues. Among others, a) shredder fines from electronics and end-of-life vehicles, and b) flue dusts from non-ferrous metallurgical processes are of timely interest. They contain valuable residuals, such as metals, that can be returned to the industrial cycle instead of being landfilled. This is one aim of the Helmholtz project FINEST in which this work is embedded.
The different finest powders need to be mixed and agglomerated for further processing. Our work in the project deals with the granular mixing. One aim is to describe particle flow based on the rheology of the bulk good while describing the mixing process among the particles using a transport equation.
The particle bulk flow in a mixing apparatus can be modelled by CFD, using e.g. FEM. The particle flow field is then coupled with the transport equation to describe the mixing process among the particles.
We are looking for someone with experience in CFD or other modelling to tackle the implementation of this model. Expertise in the numerical development of in-house multi phase flow solvers is available [Lecrivain, JCP, 2021].

Department: Particle dynamics

Contact: Baecke, Anna Magdalena, Dr. Lecrivain, Gregory

Requirements

  • Student of e.g. Process Engineering, Chemical Engineering, Computational Engineering, Mechanical Engineering, …
  • General interest in fluid mechanics and simulations
  • Preliminary experience in CFD, ideally OpenFOAM
  • Preliminary experience in code development (C++) optional

Conditions

  • Immediate start possible
  • Duration of internship or thesis according to study regulations
  • Remuneration available, scholarship holders (e.g. ERASMUS+) welcome

Online application

Please apply online: english / german

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Automatisierte Auswertung von 1D- und 2D-Ramanspektroskopischen Meßreihen (Id 393)

Bachelor theses / Master theses / Diploma theses

1D- und 2D-Ramanspektroskopische Meßreihen oder auch Maps liefern detaillierte ortsaufgelöste chemische Informationen über die untersuchten Proben. Damit kann z. B. die Komponentenverteilung in Stoffgemischen quantitativ bestimmt oder die Homogenität einphasiger Proben gezeigt werden. Andererseits lassen sich lokale Strukturveränderungen, Spannungszustände, Stapelfolgenänderungen in 2D-Materialien und Punktdefekte charakterisieren. Voraussetzung dabei ist eine möglichst engmaschige Datenerfassung bis hin zur Auflösungsgrenze der verwendeten Laserstrahlung sowie eine große Anzahl an Messpunkten. Mit modernen Spektrometern sind Messzeiten im Sekundenbereich gut realisierbar. Die Umsetzung der spektroskopischen in eine chemische Information erfordert dann die Extraktion von Parametern wie Schwingungsfrequenz, Intensität und Linienbreite durch Spektrenanpassung. Die Gerätesoftware bietet dafür nur eingeschränkte Möglichkeiten.
Im Rahmen einer Graduierungsarbeit oder Hilfstätigkeit soll in Zusammenarbeit mit dem HZDR-Rechenzentrum ein Auswertealgorithmus für die automatisierte Auswertung von 1D- und 2D-Ramanspektroskopischen Meßreihen entwickelt, an Beispielen getestet und dokumentiert werden.

Department: Nanocomposite Materials

Contact: Dr. Krause, Matthias

Requirements

1. Studium der Werkstoffwissenschaften, Physik oder Chemie
2. Interesse, Freude und Befähigung für wissenschaftliche Arbeit
3. Grundkenntnisse in Programmierung und sicherer Umgang mit Büro- und wissenschaftlicher Software
4. Sehr gute Englisch-Kenntnisse

Conditions

Die Arbeit ist in die umfangreichen Aktivitäten der Abteilung Nanoelektronik (FWIO) zu 2D-Werkstoffen eingebettet. Sie kann jederzeit aufgenommen werden.

Online application

Please apply online: english / german

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Experimental investigation of Taylor bubble shape in narrow tubes with constrictions (Id 390)

Bachelor theses / Master theses / Diploma theses / Compulsory internship / Volunteer internship

The presence of geometrical singularities in pipes may significantly affect the behavior of two-phase flow and subsequently the liquid film thickness or bubble shape. Therefore, it is an important subject of investigation in particular when the application concerns industrial safety and design.
In this work, the shape of individual air Taylor bubble in vertical tubes with constrictions subjected to counter-current liquid is experimentally performed and the influence of the obstacle on the bubble shape is analyzed. The restrictions that the constrictions on narrow tubes imposes on the motion of the interface, and its effect on the bubble shape, will be addressed in terms of geometrical and flow parameters.

In this work, the student will experimentally investigate and record high quality images and gain knowledge about experimental work regarding two-phase flow, image acquisition with MATLAB and data organization. The results will lead to the development of a flow regime map in function of diameter and viscosity.

Institute: Institute of Fluid Dynamics

Contact: Maestri, Rhandrey

Requirements

General interest in fluid mechanics;
Preliminary experience in experimental work is desirable;
Good written and oral communication skills in either English or German.

Conditions

Immediate start;
Duration of the internship is anticipated to be 3 months but can be modified according to study regulations;
Remuneration according to HZDR internal regulations.

Online application

Please apply online: english / german

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Synthesis of innovative collectors for application in recovery of metals from industrial wastewaters (Id 384)

Bachelor theses / Master theses / Diploma theses / Compulsory internship

Ion flotation and solvent extraction are promising separation processes to separate and/or remove low concentrated metals from process waters. The demand for developing special collectors (ion flotation reagent)/extractants for enhanced separation efficiency of metals using these processes is increasing due to increased demand for the metals. Further to make these processes sustainable, these special molecules need to be highly selective, efficient and ecofriendly. Strong metal binding ability is the main requisite for such novel molecules and further depending on their application, they need to behave as flotation or solvent extraction reagent. However, synthesizing novel collectors having both abilities is a challenging task. Thus, the main aim is to modify the molecules with already known metal specificity, to introduce the hydrophobicity required for the ion flotation or solvent extraction process.
This student work aims to modify the molecules by adding new functionalities and synthesizing them for improved metal complexation and process application. Additionally, their characterization as possible reagents in either flotation or solvent extraction processes will be investigated. The results will help in fundamental understanding of modified molecules in terms of their interaction with metals as well as form the basis for the development of a sustainable metal recovery process. This interdisciplinary project offers a unique integration of approaches, competences and resources in biotechnology, chemistry and process and environmental engineering and involves different departments at HIF.

Tasks:

  • Selection of hydrophobic group
  • Modification, synthesis and purification of novel molecules
  • Characterization of developed molecules, Ion flotation or solvent extraction tests

Department: Hydrometallurgy

Contact: Dr. Chakankar, Mital Vivek, Dr. Kelly, Norman, Dr. Patil, Ajay Bhagwan

Requirements

  • Field of study: Chemistry, Chemical Engineering
  • Experience in organic chemistry, knowledge of the techniques to synthesize compounds and to characterize them; experience in coordination chemistry, biochemistry and/or technical chemistry is advantageous
  • Good communication skills in German and English, spoken and written
  • Ability to work independently and systematically

Conditions

Working in a multi-disciplinary and international team, with world class research environment at HZDR and HIF.
Can get cross functional working experience and exposure to organic synthesis, modified biomolecules, solution and extractive hydrometallurgy, process biotechnology, chemical and environmental engineering

  • Working place HZDR: Location Dresden or Freiberg (HIF)
  • Start date: Either an immediate start or a start in 2023 is possible
  • Duration: 6 month
  • Remuneration according to HZDR internal regulation

Online application

Please apply online: english / german

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Internship on experimental investigation of aerosol propagation (Id 381)

Student practical training / Compulsory internship / Volunteer internship

Background:

Currently, there is a broad discussion whether ventilation by frequent window opening is sufficient for providing a sufficient amount of fresh air or if technical air purification devices based on e.g. HEPA filters are better solutions for public spaces. Furthermore, there is another discussion ongoing, whether a well-guided laminar flow or a high degree of mixing within a room is more beneficial. The latter, on the one hand distributes the potentially virus-laden aerosols in the whole room, but on the other hand reduces the peak concentrations of these aerosols clouds by magnitudes.

Objectives:

The objective is to perform aerosol propagation experiments and to estimate the potential aerosol inhalation of people in dynamic situations. To achieve this, an aerosol generator will be used in a demonstrator room under different flow conditions. The data from different scenarios will be processed in order to obtain a transference function that can relate the aerosol source with the aerosol receivers.

Tasks:

  • Literature survey
  • Aerosol experiments in different scenarios.
  • Post-processing of the results.

Department: Experimental Thermal Fluid Dynamics

Requirements

  • Student of natural sciences or engineering
  • Willingness to conduct experimental work

Conditions

Duration:

4-6 months

Remuneration:

According to HDZR guidelines

Online application

Please apply online: english / german

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Numerical simulation of particles in rising gas bubbles (Id 356)

Student practical training / Master theses / Student Assistant / Compulsory internship / Volunteer internship

The separation of aerosol particles by a moving gas-liquid fluidic interface is central to a wide variety of industrial and natural applications, among which stand out air purification systems and precipitation scavenging. The particle size significantly affects the separation rate. The diffusion of particles in the nanometer range is largely dominated by molecular diffusion. In this regime, predictive models accurately estimate the separation rates. Model inaccuracy increases, however, significantly when the particle size ranges from 0.1 μm to 2.5 μm. In this impaction-dominated regime, the complex interplay between the flow dynamics on both sides of the fluidic interface and the particle inertia makes it difficult to develop suitable models.
In this work, the student will numerically investigate whether enforcing bubble deformation into a non-spherical shape leads to a higher deposition rate, hereby making the particle separation process more efficient. The results will lead to the development of an improved and reliable separation model accounting for the deformation of the fluidic interface and the associated flow changes.

Department: Experimental Thermal Fluid Dynamics

Contact: Maestri, Rhandrey

Requirements

  • General interest in fluid mechanics
  • Preliminary experience in code development (C++) is desirable
  • Good written and oral communication skills in either English or German

Conditions

  • Either an immediate start or a start in 2024 is possible
  • Duration of the internship is anticipated to be 6 months but can be modified according to study regulations
  • Remuneration according to HZDR internal regulations

Online application

Please apply online: english / german

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Self-organized nanopattern formation on crystalline surfaces of III-V semiconductors (Id 341)

Master theses / Diploma theses

Foto: AFM images of ion-induced surface patternings ©Copyright: Dr. Denise ErbVarious metals, semiconductors, and oxides form regular nanoscale surface patterns in a complex process of self-assembly under low energy ion irradiation. Depending on both instrinsic factors of the material and externally controllable irradiation conditions, nanopatterns of very different morphologies will form, making ion-induced pattern formation a highly complex process. We study this process with regards to the material properties of various elemental and compound semiconductors, their crystal structure and surface orientation, the influence of irradiation parameters, and the patterning kinetics. Thereby, we expect to obtain new insights into the complex process of ion-induced nanopattern formation in technologically relevant materials.

We offer several projects, focussing each on a specific semiconductor material and its behavior under ion irradiation. These projects comprise the preparation of nanopatterned surfaces by low energy ion irradiation, imaging these surfaces surfaces by atomic force microscopy and electron microscopy, the quantitative analysis of these data, as well as simulating the patterning process based on continuum equations or kinetic MonteCarlo models.
The experimental work on these projects should result a diploma or M.Sc. thesis in physics, material science, or a related field of study. The provide an introduction to research at a large scale facility (Ion Beam Center IBC) and opportunities for networking with HZDR specialists on nanoscale surface modification and characterization.

Department: Ion Beam Center

Contact: Dr. Erb, Denise

Requirements

-- completed B.Sc. studies or Vordiplom in experimental physics, materials science, or related subject
-- good command of German and/or English
-- ability to work independently and systematically

Conditions

-- place of work: HZDR, location Rossendorf
-- project duration: 12 months, flexible starting time

Links:

Online application

Please apply online: english / german

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Medizinische Chemie/ Organische Synthese neuer Radioliganden für die Krebsdiagnostik und -therapie (Id 295)

Student practical training / Bachelor theses / Master theses

Wir beschäftigen uns mit der Entwicklung von PET-Radiotracern, die Rezeptoren im Tumormikromilieu (TME = tumor microenvironment) für die Diagnostik und Therapie von Krebs sichtbar machen. Dazu werden geeignete tumoraffine Leitstrukturen identifiziert (niedermolekulare organische Moleküle, Peptide und Peptidomimetika), synthetisiert und mit einem geeigneten Radionuklid kovalent (z. B. Fluor-18, Iod-123) oder über einen Chelator (z. B. Gallium-68, Lutetium-177) markiert. Diese Radioliganden werden in vitro an Tumorzelllinien und in vivo im Tiermodell hinsichtlich einer Anwendung in der Nuklearmedizin getestet. Langfristiges Ziel ist die Translation der entwickelten Radiotracer in die Klinik als Diagnosewerkzeug (PET/CT) oder nach Markierung mit einem Beta- oder Alphastrahler für die Endoradiotherapie von Tumorerkrankungen.
Im Rahmen eines Studentenpraktikums oder einer Bachelor- oder Masterarbeit sollen organische Wirkstoffmoleküle synthetisiert und für eine anschließende radiochemische Markierung modifiziert werden. Die neuen Radioliganden werden dann biologisch in vitro und in vivo untersucht.

Department: Medical Radiochemistry

Contact: Dr. Stadlbauer, Sven, Sachse, Frederik

Requirements

  • Studium der Chemie
  • Gute Noten in organischer Synthesechemie
  • Fähigkeit sich in ein interdisziplinäres Wissenschaftler-Team einzugliedern
  • Bereitschaft zum Umgang mit Radioaktivität
  • Gute Kenntnisse der deutschen und englischen Sprache

Conditions

  • Beginn nach Absprache jederzeit möglich
  • Praktikumsdauer mind. 4 Wochen, mit möglichst täglicher Anwesenheit

Online application

Please apply online: english / german

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Materials for new solar power plants (Id 241)

Bachelor theses / Master theses / Diploma theses

Foto: Solar thermal power plant ©Copyright: @AbengoaTurmkraftwerke stellen die neueste Generation von Anlagen zur solarthermischen Elektroenergieerzeugung dar (s. Abbildung). Großflächige Spiegelanordnungen konzentrieren Sonnenlicht auf einen zentralen Absorber, wo es in Wärmeenergie umwandelt wird, die dann auf ein Wärmeträgermedium übertragen wird. Gegenüber der Photovoltaik hat die Solarthermie den inhärenten Vorteil, Energie zu speichern und bei Bedarf bereit zu stellen. Die Herausforderung für die weitere Erhöhung des Wirkungsgrades von Solarkraftwerken besteht in der Entwicklung von Werkstoffen mit einer Temperaturstabilität bis zu 800 °C an Luft.
Im Rahmen von Graduierungsarbeiten und Hilfstätigkeiten sollen thermisch stabile Beschichtungen für die Kernkomponenten von Solarturmkraftwerken entwickelt und getestet werden. Dabei kommen modernste in situ und ex situ Methoden wie Magnetronsputtern, Ellipsometrie, UV-vis-NIR-FTIR-Reflektometrie und Ramanspektroskopie zur Anwendung.
Zu diesem Themenbereich werden u. a. die folgenden Aufgabenstellungen angeboten:
i) Schichtabscheidung und Optimierung der optischen und elektrischen Eigenschaften von transparenten leitfähigen Oxiden für Solarkraftwerke;
ii) Entwicklung von neuartigen Absorber- und Wärmespeicherwerkstoffen für Solarkraftwerke;
iii) Design und Simulation von solarselektiven Beschichtungen für Solarkraftwerke.

Zur Charakterisierung der untersuchten Materialien stehen modernste in situ und ex situ Analysemethoden zur Verfügung. Die Arbeiten können jederzeit aufgenommen werden.

Department: Nanocomposite Materials

Contact: Dr. Krause, Matthias

Requirements

1. Studium der Werkstoffwissenschaften, Physik oder Chemie
2. Interesse, Freude und Befähigung für experimentelle wissenschaftliche Arbeit
3. Grundkenntnisse in Programmierung und sicherer Umgang mit Büro- und wissenschaftlicher Software
4. Sichere Englischsprachkenntnisse (fließend oder besser)

Conditions

Internationale Forschungsumgebung, ortsübliche Aufwandsentschädigung

Online application

Please apply online: english / german

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