Last Updated on September 11, 2023 by Scholar Idea Helmholtz-Zentrum Dresden Rossendorf in Germany invites application for vacant PhD, Postdoc and Academic Positions, a Dresden-based research laboratory. It conducts research in three of the Helmholtz Association’s areas: materials, health, and energy. Practical trainings, student assistants and theses Switch on selection Herstellung von Si-basierten Elektroden mit höherer Si-Schichtdicke für Lithium-Ionen-Batterie (Id 400) Bachelor theses Das Flächengewicht und die Elektrodendichte werden durch den Anteil des Aktivmaterials, z. B. Silizium, in einer Elektrode bestimmt. Diese stellen die technologischen Stellschrauben für eine hohe Speicherdichte und ein optimiertes Elektrodendesign für Lithium-Ionen-Batterien (LIB) dar. In dieser Arbeit wird eine Synthese mittels Mehrschrittverfahren aus Abscheiden und Ausheilen unter Verwendung der Blitzlampenausheilung/Laser entwickelt, die das Aufbringen einer höheren Schichtdicke (bis 50 µm) des Siliziums auf z. B. Kupferfolie mit guter Homogenität und morphologischer Qualität ermöglicht. Die auszuübende Tätigkeit umfasst folgende Aufgaben: − Präparation von Si-Elektroden mittels eines Mehrschrittverfahrens mittels Abscheiden/Blitzlampenausheilung.− Zellbau von LIB- Knopfzellen− Strukturelle und elektrochemische Charakterisierung von Si-Elektroden− Literatur- und Patentrecherchen− Publikation und Präsentation wissenschaftlicher Forschungsergebnisse in referierten Fachzeitschriften und auf Veranstaltungen− Zusammenarbeit mit externen Forschungsinstitutionen und Industrie Department: Semiconductor Materials Contact: Dr. Cherkouk, Charaf Requirements Studium in Fachrichtung: Experimentalphysik, Materialwissenschaften oder ähnlichem StudiengangDatenanalyse, z. B. mittels OriginGute Sprachkenntnisse in Deutsch und/oder EnglischSelbständige und sorgfältige Arbeitsweise Conditions Arbeiten in einem internationalen und interdisziplinären TeamArbeitsort HZDR, Standort RossendorfFinanzielle Entschädigung nach HZDR-VergütungBeginn jederzeit möglich Online application Please apply online: english / german Druckversion Oberflächenmodifizierung und Grenzflächenuntersuchungen von Si-Anodenmaterialien für Lithium-Ionen-Batterien (Id 399) Master theses Silizium als Anodenmaterial (Si-Anode) wird zukünftig eine Schlüsselrolle in der neuen Generation der Lithium-Ionen-Batterien (LIB) spielen. Der Einsatz des Siliziums in der LIB anstatt des herkömmlichen Graphits lässt die Energiedichte um das Mehrfache steigern und die Ladezeiten stark reduzieren. Die Herausforderungen der Si-Anode bestehen darin, die Volumenänderung nach der Einlagerung des Lithiums einzudämmen und seine Grenzfläche zur Elektrolytseite (English, Solid-Electrolyte-Inteface, SEI) chemisch zu stabilisieren. Mit Hilfe der Nahoberflächenbehandlung, z. B. Plasma-Immersions-Ionenimplantation versuchen wir die Oberfläche der Si-Anode gezielt zu passivieren, sodass nach dem ersten Zyklus eine passive und stabile Schicht entsteht, wodurch eine Steigerung der zyklischen und kalendarischen Lebensdauer der gesamten Batteriezelle zu erwarten ist. Die auszuübende Tätigkeit umfasst folgende Aufgaben: − Synthese und Präparation von Si-Anoden mittels physikalischer/chemischer Abscheideverfahren− Oberflächennahe Behandlung von Si-Anodenmaterialien mittels Plasma-Immersions-Ionenimplantation− Zellbau von LIB- Knopfzellen− Strukturelle und elektrochemische Charakterisierung einschließlich von post-morten Untersuchungen− Literatur- und Patentrecherchen− Publikation und Präsentation wissenschaftlicher Forschungsergebnisse in referierten Fachzeitschriften und auf Veranstaltungen− Zusammenarbeit mit externen Forschungsinstitutionen und Industrie Department: Semiconductor Materials Contact: Dr. Cherkouk, Charaf Requirements Abgeschlossenes Bachelor-Studium oder Vordiplom in Experimentalphysik, Materialwissenschaften oder ähnlichem StudiengangDatenanalyse, z. B. mittels OriginGute Sprachkenntnisse in Deutsch und/oder EnglischSelbständiges und sorgfältiges Arbeiten Conditions Arbeiten in einem internationalen und interdisziplinären TeamArbeitsort HZDR, Standort RossendorfFinanzielle Entschädigung nach HZDR-VergütungBeginn jederzeit möglich Online application Please apply online: english / german Druckversion Investigation of the flow following behavior of lagrangian sensor particles in aerated reactors (Id 398) Master theses / Diploma theses / Compulsory internship Data 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 fluidsExperiments in a bubble column (330 mm ID) with LSPs and cameraData evaluation to retrieve the fluid velocity, bubble rising velocity and LSP velocityComparison 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 similarBasic chemical and fluid engineering knowledgeData analysis in PythonIndependent and structured way of working Conditions Immediate start possibleDuration according to the respective study regulations Links: Autonomous Sensor Concepts Online application Please apply online: english / german Druckversion Numerical investigation of particle mixing – internship or final thesis (Id 396) Student practical training / Bachelor theses / Master theses / Diploma theses / Compulsory internship / Volunteer internship Fine-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. 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 simulationsPreliminary experience in CFD, ideally OpenFOAMPreliminary experience in code development (C++) optional Conditions Immediate start possibleDuration of internship or thesis according to study regulationsRemuneration available, scholarship holders (e.g. ERASMUS+) welcome Links: External link Online application Please apply online: english / german Druckversion Two phase flow in a mili-/micro-fluidic channel: rare-earth extraction/stripping with/ without magnetic field (student assistant 19 h/week for 3 months + extensions) (Id 395) Student Assistant Rare earth elements are group of 17 elements in periodic table. They have unique physicochemical properties which make them essential in many high-tech components, e.g. electric mobility, laser, catalyst etc. The separation of rare earths in industry is mainly done by liquid-liquid extraction, a technique of high environmental footprint. The separation is based on the marginal difference in their affinity against the extractant used. Hence, the separation factor, a parameter quantifying the “separability” of these elements, are small. Normally, hundreds of repeating stages has to take place in plants producing multiple single rare earth products. We are actively researching a potentially more environmentally friendly alternative approach to improve the separation factor in solvent extraction of rare earths. One approach is to modulate their respective extraction kinetics. Rare-earth ions are affected due to their magnetic susceptibility in a stray field of a magnetic source. The Kelvin force that occurs, can selectively influence the extraction kinetics. Once the goal of establishing a functioning microfluidic flow system has been achieved, a magnetic field can be applied. Various experiments are carried out to separate rare earths in this way. This allows conclusions to be drawn about the reaction kinetics and a deeper understanding of the physical chemical processes can be obtained. For promising candidates there is subsequently the opportunity (Belegarbeit/ Diplomarbeit)) for further employment. Department: Transport processes at interfaces Contact: Bidmon, Alexander, Dr. Lei, Zhe Requirements 1. Interest on applied optical experiment2. Basic chemical and fluid engineering knowledge3. can handle common lab chemicals4. Work conscientiously and safely5. Capable of communication and some basic data analysis skill Conditions 1. Design and assembly the experimental setup of two two-phase-flow systems, one with a slug-flow and one with a parallel-flow of aqueous and organic solution (Fig 1).2. Add and adjust pumping system and creation control program3. UV – Vis Spectroscopy for different rare-earth concentrations4. Experimental study with/ without applied magnetic field Online application Please apply online: english / german Druckversion Automatisierte Auswertung von 1D- und 2D-Ramanspektroskopischen Meßreihen (Id 393) Student practical training / Bachelor theses / Master theses / Diploma theses / Student Assistant / Research Assistant 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 Chemie2. Interesse, Freude und Befähigung für wissenschaftliche Arbeit3. Grundkenntnisse in Programmierung und sicherer Umgang mit Büro- und wissenschaftlicher Software4. 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 Druckversion Two phase flow in a mili-/micro-fluidic channel: rare-earth extraction/stripping with/ without magnetic field (student assistant 19 h/week for 3 months + extensions) (Id 392) Student Assistant Rare earth elements are group of 17 elements in periodic table. They have unique physicochemical properties which make them essential in many high-tech components, e.g. electric mobility, laser, catalyst etc. The separation of rare earths in industry is mainly done by liquid-liquid extraction, a technique of high environmental footprint. The separation is based on the marginal difference in their affinity against the extractant used. Hence, the separation factor, a parameter quantifying the “separability” of these elements, are small. Normally, hundreds of repeating stages has to take place in plants producing multiple single rare earth products. We are actively researching a potentially more environmentally friendly alternative approach to improve the separation factor in solvent extraction of rare earths. One approach is to modulate their respective extraction kinetics. Rare-earth ions are affected due to their magnetic susceptibility in a stray field of a magnetic source. The Kelvin force that occurs, can selectively influence the extraction kinetics. Once the goal of establishing a functioning microfluidic flow system has been achieved, a magnetic field can be applied. Various experiments are carried out to separate rare earths in this way. This allows conclusions to be drawn about the reaction kinetics and a deeper understanding of the physical chemical processes can be obtained. For promising candidates there is subsequently the opportunity (Belegarbeit/ Diplomarbeit)) for further employment. Department: Transport processes at interfaces Contact: Bidmon, Alexander, Dr. Lei, Zhe Requirements 1. Interest on applied optical experiment2. Basic chemical and fluid engineering knowledge3. can handle common lab chemicals4. Work conscientiously and safely5. Capable of communication and some basic data analysis skill Conditions 1. Design and assembly the experimental setup of two two-phase-flow systems, one with a slug-flow and one with a parallel-flow of aqueous and organic solution (Fig 1).2. Add and adjust pumping system and creation control program3. UV – Vis Spectroscopy for different rare-earth concentrations4. Experimental study with/ without applied magnetic field Online application Please apply online: english / german Druckversion 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 Druckversion Student assistant wanted in the area of technology transfer and innovation (Id 389) Student Assistant Your tasks: Participation in the screening of potential research resultsInternet and database research for market, competition and patent analysesPreparation of exploitation and business plans for spin-offsPreparation of cost calculations and financial plansPreparation of technology exposésPreparation of presentationsDatabase maintenance, reporting, evaluation of data on transfer indicatorsAfter individual consultation, independent processing of various projects (e.g. conception and support of reporting system & benchmarking etc.) Department: Technology Transfer & Innovation Contact: Pöpping, Uwe, Dr. Wolf, Björn Requirements You are studying industrial engineering, economics or another degree (especially STEM) with a partial business qualification. You have significant practical experience in the relevant areas and have good MS Office skills. You work independently, in a structured manner, can quickly familiarise yourself with new tasks and are happy to contribute to a motivated team. You have a very good knowledge of English. Conditions We offer you exciting and challenging tasks, a collegial and international working environment, active support in the implementation of your tasks as well as scope for decision-making and responsibility. The place of work is Dresden-Rossendorf. Some of the tasks can be carried out at home by arrangement. The duration of the SHK activity (min. 5 h/week) should be at least one year. Online application Please apply online: english / german Druckversion Master’s thesis “Analysis of existing incentive systems and development of a new incentive/bonus system to motivate transfer activities in a scientific institution” (Id 388) Master theses / Student Assistant The HZDR makes significant contributions to solving the major challenges facing society – with real, concrete and measurable benefits and impact. The HZDR is committed to excellence and a leading international position, not only in research and the operation of large research infrastructures, but also in transfer. Knowledge and technology transfer are directly part of the HZDR’s social mission and statutory purpose. The HZDR’s mission statement states: “By actively exploiting its research results, the HZDR makes a significant contribution to the future viability of the economy and society”.With its Transfer Strategy 2025+, the HZDR has set itself the overarching goal of further increasing its success in the field of knowledge and technology transfer, while at the same time expanding the visibility of the HZDR.Measures have been defined to implement the strategy, including the development of suitable incentive systems for scientific staff as well as management levels.The aim of this work is to record the current incentive system and to work out the weaknesses, taking into account current literature and existing surveys at the HZDR. Based on these results, a new incentive system is to be developed with the involvement of stakeholders at the centre (surveys, workshops). Department: Technology Transfer & Innovation Contact: Pöpping, Uwe Requirements You are studying industrial engineering, economics or another degree (especially STEM) with a partial business qualification. You have significant practical experience in the relevant areas and have good MS Office skills. You work independently, in a structured manner, can quickly familiarise yourself with new tasks and are happy to contribute to a motivated team. You have a very good knowledge of English. Conditions We offer you exciting and challenging tasks, a collegial and international working environment, active support in the implementation of your tasks as well as scope for decision-making and responsibility. The place of work is Dresden-Rossendorf. Some of the tasks can be carried out at home by arrangement. The duration of the SHK activity (min. 5 h/week) should be at least one year, that of the Master’s thesis (full-time) should be at least 3 months. Online application Please apply online: english / german Druckversion Two phase flow in a mili-/micro-fluidic channel: rare-earth extraction/stripping with/ without magnetic field (student assistant 19 h/week for 3 months + extensions) (Id 386) Student Assistant Rare earth elements are group of 17 elements in periodic table. They have unique physicochemical properties which make them essential in many high-tech components, e.g. electric mobility, laser, catalyst etc. The separation of rare earths in industry is mainly done by liquid-liquid extraction, a technique of high environmental footprint. The separation is based on the marginal difference in their affinity against the extractant used. Hence, the separation factor, a parameter quantifying the “separability” of these elements, are small. Normally, hundreds of repeating stages has to take place in plants producing multiple single rare earth products. We are actively researching a potentially more environmentally friendly alternative approach to improve the separation factor in solvent extraction of rare earths. One approach is to modulate their respective extraction kinetics. Rare-earth ions are affected due to their magnetic susceptibility in a stray field of a magnetic source. The Kelvin force that occurs, can selectively influence the extraction kinetics. Once the goal of establishing a functioning microfluidic flow system has been achieved, a magnetic field can be applied. Various experiments are carried out to separate rare earths in this way. This allows conclusions to be drawn about the reaction kinetics and a deeper understanding of the physical chemical processes can be obtained. For promising candidates there is subsequently the opportunity (Belegarbeit/ Diplomarbeit)) for further employment. Department: Transport processes at interfaces Requirements 1. Interest on applied optical experiment2. Basic chemical and fluid engineering knowledge3. can handle common lab chemicals4. Work conscientiously and safely5. Capable of communication and some basic data analysis skill Conditions 1. Design and assembly the experimental setup of two two-phase-flow systems, one with a slug-flow and one with a parallel-flow of aqueous and organic solution (Fig 1).2. Add and adjust pumping system and creation control program3. UV – Vis Spectroscopy for different rare-earth concentrations4. Experimental study with/ without applied magnetic field Online application Please apply online: english / german Druckversion Two phase flow in a mili-/micro-fluidic channel: rare-earth extraction/stripping with/ without magnetic field (student assistant 19 h/week for 3 months + extensions) (Id 385) Student Assistant Rare earth elements are group of 17 elements in periodic table. They have unique physicochemical properties which make them essential in many high-tech components, e.g. electric mobility, laser, catalyst etc. The separation of rare earths in industry is mainly done by liquid-liquid extraction, a technique of high environmental footprint. The separation is based on the marginal difference in their affinity against the extractant used. Hence, the separation factor, a parameter quantifying the “separability” of these elements, are small. Normally, hundreds of repeating stages has to take place in plants producing multiple single rare earth products. We are actively researching a potentially more environmentally friendly alternative approach to improve the separation factor in solvent extraction of rare earths. One approach is to modulate their respective extraction kinetics. Rare-earth ions are affected due to their magnetic susceptibility in a stray field of a magnetic source. The Kelvin force that occurs, can selectively influence the extraction kinetics. Once the goal of establishing a functioning microfluidic flow system has been achieved, a magnetic field can be applied. Various experiments are carried out to separate rare earths in this way. This allows conclusions to be drawn about the reaction kinetics and a deeper understanding of the physical chemical processes can be obtained. For promising candidates there is subsequently the opportunity (Belegarbeit/ Diplomarbeit)) for further employment. Department: Transport processes at interfaces Contact: Bidmon, Alexander, Dr. Lei, Zhe Requirements 1. Interest on applied optical experiment2. Basic chemical and fluid engineering knowledge3. can handle common lab chemicals4. Work conscientiously and safely5. Capable of communication and some basic data analysis skill Conditions 1. Design and assembly the experimental setup of two two-phase-flow systems, one with a slug-flow and one with a parallel-flow of aqueous and organic solution (Fig 1).2. Add and adjust pumping system and creation control program3. UV – Vis Spectroscopy for different rare-earth concentrations4. Experimental study with/ without applied magnetic field Online application Please apply online: english / german Druckversion Synthesis of innovative collectors for application in recovery of metals from industrial wastewaters (Id 384) Master theses / Diploma theses 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 groupModification, synthesis and purification of novel moleculesCharacterization 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 EngineeringExperience in organic chemistry, knowledge of the techniques to synthesize compounds and to characterize them; experience in coordination chemistry, biochemistry and/or technical chemistry is advantageousGood communication skills in German and English, spoken and writtenAbility 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 possibleDuration: 6 monthRemuneration according to HZDR internal regulation Online application Please apply online: english / german Druckversion 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 surveyAerosol experiments in different scenarios.Post-processing of the results. Department: Experimental Thermal Fluid Dynamics Requirements Student of natural sciences or engineeringWillingness to conduct experimental work Conditions Duration: 4-6 months Remuneration: According to HDZR guidelines Online application Please apply online: english / german Druckversion 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 mechanicsPreliminary experience in code development (C++) is desirableGood written and oral communication skills in either English or German Conditions Either an immediate start or a start in 2024 is possibleDuration of the internship is anticipated to be 6 months but can be modified according to study regulationsRemuneration according to HZDR internal regulations Online application Please apply online: english / german Druckversion Unterstützung im Rechnungswesen (Id 351) 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 GeschäftsvorfällenUnterstützung (SAP) bei der Stammdatenpflege, insbesondere KreditorenSonstige Unterstützungstätigkeiten Department: Finance, Financial Controlling and Third-party Funds Contact: Hartwig, Patrick Requirements Begonnenes Studium der WirtschaftswissenschaftenErste Kenntnisse in den Grundlagen des Rechnungswesens (Buchführung, Kosten- und Leistungsrechnung)Selbstständige und verantwortungsvolle Arbeitsweise Conditions Arbeitsbeginn ab sofortMindestens 6 Monate Wir bieten Ihnen die Möglichkeit, im Studium Erlerntes praxisnah umzusetzen! Es erwarten Sie einmotiviertes 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 Druckversion Calculation of multi-phase flow using the GENTOP model with FLUENT (Id 346) Master theses / Diploma theses / Compulsory internship As a member of the Helmholtz Association of German Research Centers, the HZDR employs about 1,400 people. The Center’s focus is on interdisciplinary research in the areas energy, health and matter. The Institute of Fluid Dynamics is conducting basic and applied research in the fields of thermo-fluid dynamics and magnetohydrodynamics in order to improve the sustainability, the energy efficiency and the safety of industrial processes. Multiphase flows are important part of many industrial applications, whereas modelling of them is a challenging and complex task. For flow situations with higher void fractions, HZDR developed a new generalized concept for the CFD-simulations including flow regime transitions. The GENTOP (Generalized Two-Phase Flow) approach is able to simulate co-existing large-scaled (continuous) and small-scaled (polydispersed) structures (Fig. 1). Previous results were performed with the CFD code CFX and compared against DEBORA validation data. The goal of the thesis would be to apply and improving the existing state of the simulations in the Fluent GENTOP framework. We offer an interesting task dealing with complex physical phenomena, work in an international team using state-of-the-art calculation and programming methods. We are looking for a motivated student (f/m/d) (master thesis) able to perform CFD simulations, understand and program code to generalize/parametrize CFD simulations, work with experimental data sets, document and present the work in an appropriate manner. Useful but not required is a knowledge of the following software tools: CFD codes CFX and Fluent, Python, GIT. The task is supervised by Framatome and HZDR. FRAMATOME is a designer and supplier of nuclear steam supply system and nuclear equipment, services and fuel for high levels of safety and performance. Framatome is a major international player in the nuclear energy market recognized for its innovative solutions and value-added technologies for designing, building, maintaining, and advancing the global nuclear fleet. The company designs, manufactures, and installs components, fuel and instrumentation and control systems for nuclear power plants and offers a full range of reactor services. With 14,000 employees worldwide, every day Framatome’s expertise helps its customers improve the safety and performance of their nuclear plants and achieve their economic and societal goals. Department: Computational Fluid Dynamics Contact: Dr. Höhne, Thomas, Dr. Lucas, Dirk Requirements Studies in Engineering, Computer Science or comparableInterest in numerical workGood communication skills in both written and spoken EnglishUseful but not required is a knowledge of the following software tools: CFD codes CFX and Fluent, Python, GIT. Conditions A vibrant research community in an open, diverse, and international work environment.Scientific excellence and extensive professional networking opportunities.Compensation as student researcher (working hours to be determined).Working place will be Dresden and/or Erlangen Germany. Online application Please apply online: english / german Druckversion Self-organized nanopattern formation on crystalline surfaces of III-V semiconductors (Id 341) Master theses / Diploma theses Various 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: Pattern formation and surface analytics Online application Please apply online: english / german Druckversion Organisch-chemische Synthese neuer Radioliganden für die Diagnostik und Therapie von Krebserkrankungen (Id 295) Student practical training / Bachelor theses / Master theses / Diploma 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 Abschlussarbeit (Bachelor/Master/Diplom) 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: Translational TME Ligands Contact: Dr. Stadlbauer, Sven, Sachse, Frederik Requirements Studium der ChemieGute Noten in organischer SynthesechemieFähigkeit sich in ein interdisziplinäres Wissenschaftler-Team einzugliedernBereitschaft zum Umgang mit RadioaktivitätGute Kenntnisse der deutschen und englischen Sprache Conditions Beginn nach Absprache jederzeit möglichPraktikumsdauer mindestens 8 Wochen, mit möglichst täglicher Anwesenheit (keine wiss. Hilfskräfte)Vergütung erfolgt nach HDZR-Richtlinien Online application Please apply online: english / german Druckversion Materials for new solar power plants (Id 241) Bachelor theses / Master theses / Diploma theses / Student Assistant / Research Assistant Turmkraftwerke 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 Chemie2. Interesse, Freude und Befähigung für experimentelle wissenschaftliche Arbeit3. Grundkenntnisse in Programmierung und sicherer Umgang mit Büro- und wissenschaftlicher Software4. Sichere Englischsprachkenntnisse (fließend oder besser) Conditions Internationale Forschungsumgebung, ortsübliche Aufwandsentschädigung Online application Please apply online: english / german Druckversion Post navigation The German Cancer Research Center (DKFZ) invites application for vacant (57) PhD, Postdoctoral and Academic Positions Alfaisal University in Saudi Arabia invites applications for vacant (57) Research and Academic Positions