Decommissioning and dismantling of the Rossendorf Isotope Production

International Nuclear Information System (INIS)

Grahnert, Thomas

2016-01-01

After just over 40 years of production operation 2000, the operation of the Rossendorf Isotope Production was finally stopped. In the last few years of production already sections of the Rossendorf Isotope Production have been decommissioned. With the end of the isotope production the decommissioning of the entire complex started. In the two-part report, the decommissioning and dismantling of the Rossendorf Isotope production is presented. In part 1 (atw 5/2016) mainly the authorisation procedures and the realised decommissioning concept are presented. Part 2 (atw 6/2016) deals with special selected aspects of the implementation of the decommissioning programme.

The establishment of the Rossendorf PET Center

International Nuclear Information System (INIS)

Johannsen, B.; Steinbach, J.

1993-01-01

The objectives of the newly established Positron Emission Tomography (PET) Center at the Institut of Bioinorganic and Radiopharmaceutical Chemistry in Rossendorf are described, referring to medical research, development of tracers and radiochemicals developments, biochemistry and future prospects of PET in Rossendorf. The layout of the center is also described considering the cyclotron and targetry, the transport system, the radiopharmaceutical laboratories and the tomograph. A schedule for project development is going. (BBR)

Annual report 1983

International Nuclear Information System (INIS)

Muenze, R.

1984-10-01

The development of radioactive compounds and methods for producing radionuclides in the ZfK Rossendorf are reviewed. The growth in isotope production is mainly due to increasing 99 Mo and generator production. Investigations on /sup 99m/Tc for the purpose of producing new radiopharmaceuticals are reported. In the field of labelled compounds the researches were intensively concerned with 14 C and 3 H compounds

20 years Rossendorf cyclotron

International Nuclear Information System (INIS)

1978-08-01

On the occasion of the 20th anniversary of initiating of the Rossendorf cyclotron accounts are given of most important works and results in the field of accelerator engineering and utilization of this machine. The reports show the trend of development and actual spectrum of application. The enclosed literature lists give a survey of technical and experimental works at cyclotron. (author)

Accelerator mass spectrometry at the Rossendorf 5 MV tandem accelerator

International Nuclear Information System (INIS)

Friedrich, M.; Buerger, W.; Curian, H.; Hartmann, B.; Hentschel, E.; Matthes, H.; Probst, W.; Seidel, M.; Turuc, S.; Hebert, D.; Rothe, T.; Stolz, W.

1992-01-01

The Rossendorf electrostatic accelerators (5 MV tandem accelerator and single ended 2 MV van de Graaff accelerator) are already used for ion beam analysis. The existing methods (RBS, PIXE, ERDA, NRA, nuclear microprobe and external beam) will be completed by introduction of Accelerator Mass Spectrometry (AMS). A short description of the Rossendorf AMS system is given and first experimental results are presented. (R.P.) 4 refs.; 6 figs

Annual Report 1985

International Nuclear Information System (INIS)

Muenze, R.

1986-06-01

This annual report covers the work carried out at the Radioisotope Department, ZfK Rossendorf, during the year 1985. It contains 12 contributions related to the development of processes for generating radioisotopes, 23 contributions related to the synthesis of radioactive compounds, and 26 contributions related to the characterization of radioactive compounds. All contributions are published in summary form only and are individually processed for the INIS database. Additionally, a list is given of publications and lectures issued between January and December 1985

Forschungszentrum Rossendorf. Institute of Safety Research. Annual report 1998

International Nuclear Information System (INIS)

Weiss, F.P.; Rindelhardt, U.

1999-07-01

The Institute of Safety Research is one of the five scientific institutes of Forschungszentrum Rossendorf e.V. The Forschungszentrum Rossendorf is a member of the 'Wissenschaftsgemeinschaft Gottfried Wilhelm Leibniz' und is funded by the Federal Ministry of Education and Research and by the Saxon Ministry of Science and Arts with 50% each. The research work of the institute aims at the assessment and increase of the safety and environmental sustainability of technical plants. The emphasis is put on the development and validation of mathematical and physical models for process and plant analysis, and of techniques for process and components monitoring. Subject of investigations are equally nuclear plants and installations of process industries. (orig.)

A shielding chamber for the Rossendorf whole-body counter; Eine Abschirmkammer fuer den Rossendorfer Ganzkoerperzaehler

Energy Technology Data Exchange (ETDEWEB)

Ebert, Stephan; Loehnert, Daniela [VKTA - Strahlenschutz, Analytik und Entsorgung Rossendorf e.V., Dresden (Germany).; Schreiber, Wolfgang [Ingenieurbedarf G. Schoene und W. Schreiber GmbH, Radeberg (Germany)

2017-08-01

A large part of radionuclides to be evaluated in the frame of incorporation monitoring are gamma emitter that can be directly measured (in vivo). In order to reach the required detection limits for the relevant radionuclides in the short measuring time high effort is necessary for the shielding of natural radioactivity. The contribution describes planning, construction and installation of the shielding chamber for the new in vivo whole body counter in Rossendorf. First experiences and preliminary results are discussed.

Verein fuer Kernverfahrenstechnik und Analytik Rossendorf. Annual report 1992

International Nuclear Information System (INIS)

Haefele, W.

1993-04-01

The Association was founded to start its operation on Jan. 1, 1992. It is funded entirely by the State of Saxony. The Charta of the Association states the following: 'It is the purpose of the Association to maintain and to foster knowledge and capabilities in the field of nuclear engineering and related areas. Above that, it is the purpose, to build, to operate and/or to terminate particular nuclear facilities and to hold the related nuclear licenses. This includes the field of remediation as well as nuclear and chemical analysis.' Actually it is the nuclear facilities at Rossendorf that must be maintained and kept in safe conditions exept for those that are part of the Research Center Rossendorf which had been founded at the same time. Further, it the intent to make use of the nuclear analytical and chemical expertise that exists at Rossendorf, when the remediation of larger areas must be accomplished that were spoiled for decades by various mining activities. Besides of scientific and technical matters there are legal and administrative implications up to the point of governmental concerns that must be appropriatly taken into account. Above all it is matter of cost optimisation. During the first year of its existence the Association had organised its various tasks and priorities, it started to work. (orig./HP) [de

The environmental and radionuclide laboratory at VKTA Rossendorf; Das Labor fuer Umwelt- und Radionuklidanalytik im VKTA Rossendorf

Energy Technology Data Exchange (ETDEWEB)

Koehler, M.; Knappik, R.; Gleisberg, B.; Schaefer, I.; Boden, W.; Bothe, M. [Verein fuer Kernverfahrenstechnik und Analytik Rossendorf e.V. (VKTA), Dresden (Germany)

2001-07-01

The VKTA provides environmental and radionuclide analyses for remediation and waste management tasks at the Rossendorf research site and for commercial clients as well. The analyses, the correlated valuations and calculations were used for the decommissioning of nuclear facilities, for the remediation of contaminated mining sites and for environmental investigations. The Laboratory for Environmental and Radionuclide Analytics is able to handle and analyse artificial and natural radionuclides in the range from 10{sup -3} Bq until 10{sup 9} Bq. Besides the used activity measurement techniques ({alpha}-particle and {gamma}-ray spectrometry, {beta}-counting), which were also applied after radiochemical separations, mass-spectrometry with inductively coupled plasma provides analytical results for long-lived radionuclides and isotopic ratios very effective. The capability of the laboratory is demonstrated by selected applications. (orig.) [German] Der VKTA fuehrt im Rahmen seiner Rueckbau- und Entsorgungsaufgaben am Forschungsstandort Rossendorf und fuer externe Auftraggeber Umwelt- und Radionuklidanalysen als komplexe Dienstleistung durch. Die Analysen und die damit in Zusammenhang stehenden Bewertungen und Modellrechnungen finden beim Rueckbau kerntechnischer Anlagen, bei der Sanierung von Uranbergbau-Altlasten und im Umweltbereich Verwendung. Im Labor fuer Umwelt- und Radionuklidanalytik werden Proben mit kuenstlichen und natuerlichen Radionukliden im typischen Aktivitaetsbereich von 10{sup -3} Bq bis 10{sup 9} Bq bearbeitet und analysiert. Neben den Aktivitaetsmessverfahren ({alpha}-, {beta}-, {gamma}-Spektrometrie), die auch nach radiochemischen Trennungen eingesetzt werden, kommen massenspektrometrische Verfahren bei der Analyse langlebiger Radionuklide bzw. Isotopenverhaeltnisse zum Einsatz. Das Leistungsspektrum des Labors wird durch ausgewaehlte Applikationen belegt. (orig.)

Contributions of FZ Rossendorf to the IAEA standard problem exercise no. 4

International Nuclear Information System (INIS)

Krepper, E.; Prasser, H.M.; Schaefer, F.

1995-01-01

Research Center Rossendorf contributed to the SPE-4 experiment by supplying needle shaped conductivity probes for the measurement of local void fractions in the primary circuit of the PMK-II test facility. The probes were developed for the application under primary circuit conditions, where they have to withstand high mechanical and corrosive loads. As a part of the cooperation the probes from Rossendorf have already been applied to various experiments at PMK in the past. During SPE-4 the probes were placed practically all around the circuit (with exception of the core simulator and the downcomer) and for the first time they have provided data which characterise the phase distribution within the whole primary circuit. (orig./HP)

Presentation of the program of quality for health physics measurement-instrumentation at the Rossendorf research center; Vorstellung des Qualitaetssicherungsprogramms Strahlenschutzmesstechnik am Forschungsstandort Rossendorf

Energy Technology Data Exchange (ETDEWEB)

Roellig, D. [VKTA, Dresden (Germany)

2016-07-01

In the facilities of the research center Rossendorf ionizing radiation and radioactive materials are used in many ways. Radiation protection devices ensure their safe handling. The quality of these devices has to be monitored to protect personnel and environment from unacceptably high radiation levels at all times. For that a quality control program was developed whose details are explained in the poster.

Forschungszentrum Rossendorf. Institute of Safety Research. Report. January 1998 - June 1999

Energy Technology Data Exchange (ETDEWEB)

Weiss, F P; Rindelhardt, U [eds.

1999-09-01

The Institute of Safety Research is one of the five scientific institutes of Forschungszentrum Rossendorf e.V. The Forschungszentrum Rossendorf is a member of the 'Wissenschaftsgemeinschaft Gottfried Wilhelm Leibniz' and is funded by the Federal Ministry of Education and Research and by the Saxon Ministry of Science and Arts with 50% each. The research work of the institute aims at the assessment and increase of the safety and environmental sustainability of technical plants. The emphasis is put on the development and validation of mathematical and physical models for process and plant analysis, and of techniques for process and components monitoring. Subject of investigations are equally nuclear plants and installations of process industries. To analyse the thermo-fluiddynamics of normal plant operation and of the behaviour during accidents, physical models and computer codes are developed for multi-phase and multi-component flows, and for the space and time dependent heat release (neutron kinetics, chemical kinetics). (orig.)

Forschungszentrum Rossendorf. Institute of Safety Research. Report. January 1998 - June 1999

Energy Technology Data Exchange (ETDEWEB)

Weiss, F.P.; Rindelhardt, U. [eds.

1999-09-01

The Institute of Safety Research is one of the five scientific institutes of Forschungszentrum Rossendorf e.V. The Forschungszentrum Rossendorf is a member of the 'Wissenschaftsgemeinschaft Gottfried Wilhelm Leibniz' and is funded by the Federal Ministry of Education and Research and by the Saxon Ministry of Science and Arts with 50% each. The research work of the institute aims at the assessment and increase of the safety and environmental sustainability of technical plants. The emphasis is put on the development and validation of mathematical and physical models for process and plant analysis, and of techniques for process and components monitoring. Subject of investigations are equally nuclear plants and installations of process industries. To analyse the thermo-fluiddynamics of normal plant operation and of the behaviour during accidents, physical models and computer codes are developed for multi-phase and multi-component flows, and for the space and time dependent heat release (neutron kinetics, chemical kinetics). (orig.)

Analysis of the Rossendorf SEG experiments using the JNC route for reactor calculation

International Nuclear Information System (INIS)

Dietze, Klaus

1999-11-01

The integral experiments performed at the Rossendorf fast-thermal coupled reactor RRR/SEG have been reanalyzed using the JNC route for reactor calculation JENDL3.2/SLAROM/CITATION/JOINT/PERKY. The Rossendorf experiments comprise sample reactivity measurements with pure fission products and structural material in five configurations with different neutron and adjoint spectra. The shapes of the adjoint spectra have been designed to get high sensitivities to neutron capture or the scattering effect. The calculated neutron and adjoint spectra are in good agreement with former results obtained with the European route JEF2.2/ECCO/ERANOS. The C/E-values of the central reactivity worths of samples under investigation are given. Deviations in the results of both routes are due to the different libraries, codes, and self-shielding treatments used in the calculations. Results exceeding the experimental error are discussed. (author)

Forschungszentrum Rossendorf, Institute of Ion Beam Physics and Materials Research. Annual Report 1994

International Nuclear Information System (INIS)

Moeller, W.; Wieser, E.; Kirch, S.

1995-03-01

This volume contains the 1994 annual report describing the scientific activity of the Institute of Ion Beam Physics and Material Research (Forschungszentrum Rossendorf, FZR). This institute is devoted to the application of ion beams for the modification and analysis of near-surface layers of solids. (MSA)

30 years of Central Institute for Nuclear Research at Rossendorf

International Nuclear Information System (INIS)

Scheler, W.; Flach, G.; Hennig, K.; Collatz, S.; Muenze, R.; Baldeweg, F.

1986-10-01

A celebration and a scientific colloquium dedicated the 30th anniversary of the foundation of the Central Institute for Nuclear Research (CINR) of the GDR Academy of Sciences were held on January, 23rd and 24th, '86 at Rossendorf. The speaches and lectures given by the president of the GDR Academy of Sciences and by scientists of the CINR dealt with problems of policy of science, history of the CINR, nuclear methods, microelectronics, nuclear energy research, development and production of radioisotopes and scientific instruments. (author)

VKTA Rossendorf: Laboratory for Environmental and Radionuclide Analysis

International Nuclear Information System (INIS)

Koehler, M.; Knappik, R.; Fiola, K.

2015-01-01

The VKTA (Nuclear Engineering and Analytics Inc.) is charged by the Free State of Saxony with the decommissioning and waste management of the nuclear installations at the research site Dresden-Rossendorf. This task includes the safe management and disposal of fissile material and radioactive wastes. The acquired expertise and our solution-oriented way of working are the basis for a varied range of services especially the environmental and radionuclide analyzes. The Laboratory for Environmental and Radionuclide Analysis is accredited according to DIN EN ISO/IEC 17025 and provides a sound range of analytical and metrological services including their coordination and management. The personnel and the rooms, measuring and technical equipment are particularly designed for our special field, the measuring of radioactivity. We are focussed on measuring artificial and natural radionuclides in a wide range of activity and in different sample matrices (e.g., urine, faeces, metals, soil, concrete, food, liquids). With the flexible accreditation of the radionuclide analytics the Laboratory is able to react shortly to changing requirements in decommissioning, environmental monitoring and radiation protection. Essential chemical and radiochemical methods are e.g.: · Alpha particle spectrometry, · Liquid scintillation counting, · gamma ray spectrometry, including Ultra-Low-Level, · High-resolution ICP-MS, · Chromatographic methods such as ion chromatography, gas chromatography, HPLC, · Electrochemical measuring methods such as potentiometry, voltammetry. The Laboratory offers analytical services to the research site Dresden-Rossendorf and national and international customers adapting its analytical procedures to the special needs of customers. The presentation demonstrates on the basis of examples the work of Laboratory within the scope of decommissioning of nuclear facilities, especially at a research site, from radiological preliminary investigation to declaration of

Safeguards at the Central Institute for Nuclear Research at Rossendorf/GDR

International Nuclear Information System (INIS)

Helming, M.; Rehak, W.; Schillert, B.

1989-01-01

Experience in the implementation of domestic and international safeguards at the Central Institute for Nuclear Research at Rossendorf is reported covering the following topics: overview of the main nuclear installations belonging to the Institute; structure of its material balance areas; responsibilities for the different aspects of accounting for and control of nuclear material at facility level; the various types of nuclear materials handled and their flow, accessibility and strategic significance; the assessment of IAEA safeguards effectiveness. 2 tabs., 2 figs. (author)

The Rossendorf research reactor. Operating and dismantling from a point of view of the emission control; Der Rossendorfer Forschungsreaktor. Betrieb und Rueckbau aus Sicht der Emissionsueberwachung

Energy Technology Data Exchange (ETDEWEB)

Bauer, B.; Beutmann, A.; Kaden, M.; Scheibke, J. [VKTA, Dresden (Germany); Boessert, W.; Jansen, K.; Walter, M.

2016-07-01

The Rossendorf research reactor went in operation in 1957 as GDR's first nuclear reactor and Germanys second after FRM Garching. It was a heterogeneously structured, light-water moderated and cooled tank-reactor of the Soviet type WWR-S. During his time of operation, he served both the research and the production of radioisotopes. The history of exhaust air emission monitoring and its results are presented. With view to the decommissioning time selected results are discussed. The estimated discharges are compared by the actually recognized.

Backfitting in Rossendorf research reactor control and instrumentation system

International Nuclear Information System (INIS)

Klebau, J.; Seidler, S.

1985-01-01

The paper generally describes a decentralized Hierarchical Information System (HIS) which has been developed for backfitting in Rossendorf Research Reactor (RFR) control and instrumentation system. The RFR was put into operation in 1957 and reconstructed from 2 MW up to a thermal power of 10 MW at the end of the sixties. Backfitting is planned by use of an advanced computerized control system for the next years. Main tasks of HIS are: Processmonitoring, online-disturbance analysis, technical diagnosis, direct digital control and use of a special industrial robot for discharging of irradiated materials out of the reactor. Experiences obtained by HIS during a testperiod will be presented. (author)

The Rossendorf Beamline at ESRF (ROBL-CRG). Bi-annual report 2003/04

Energy Technology Data Exchange (ETDEWEB)

Scheinost, A.C.; Schell, N. (eds.)

2005-01-01

In this report the work performed at the Rossendorf beam-line at the ESRF is described. It concerns neptunium (IV) uptake by iron metalloproteins, in-situ speciation of actinides using a newly developed spectro-electrochemical cell, quantitative antimony speciation in Swiss shooting-range soils, in-situ studies of ITO film properties and structure during annealing in vacuum, high-temperature investigations of Si/SiGe based quantum cascade structures using X-ray diffraction and reflectivity, and in-situ characterization of stress states in copper dual inlaid interconnects at high temperatures by synchrotron X-ray diffraction. (HSI)

Forschungszentrum Rossendorf, Institute of Radiochemistry. Annual report 2004

Energy Technology Data Exchange (ETDEWEB)

Bernhard, G [ed.

2005-07-01

The Institute of Radiochemistry (IRC), one of the six Institutes of the Forschungszentrum Rossendorf (FZR) performs basic and applied research in the fields of radiochemistry and radioecology. Motivation and background of our research are environmental processes relevant for the installation of nuclear waste repositories, for remediation of uranium mining and milling sites, and for radioactive contaminations caused by nuclear accidents and fallout. Because of their high radiotoxicity and long half-life the actinides are of special interest. The research is focused on a better understanding of the chemical behavior of actinides in the environment on a molecular level. We will increase our efforts to study both the speciation of actinides on bio-molecular interfaces and their transport in bio-systems. Current topics of our research work are: aquatic chemistry of actinides, actinides in bio-systems, interaction of actinides with solid phases, Reactive transport of actinides. About 60 scientists, technicians and PhD students are employed at the Institute of Radiochemistry. We accomplished many new scientific results in the past year, which are presented in this annual report. Among them only few can be highlighted in this preface. Further progress was achieved in understanding the formation and characterization of uranium containing colloids. The newly installed method of laser-induced breakdown detection was very helpful for the identification of uranium colloids under anoxic conditions. We were very successful in the determination of formation pathways and structure of various actinide complexes. These results contribute to a better understanding of actinide speciation in geo- and bio-systems, especially with respect to the chemical processes on the interfaces. The results achieved in the characterization of the properties, modification, and interaction of the S-layers of Bacillus sphaericus with uranium and some other heavy metals strengthen our hope to use this

Forschungszentrum Rossendorf, Institute of Radiochemistry. Annual report 2004

International Nuclear Information System (INIS)

Bernhard, G.

2005-01-01

The Institute of Radiochemistry (IRC), one of the six Institutes of the Forschungszentrum Rossendorf (FZR) performs basic and applied research in the fields of radiochemistry and radioecology. Motivation and background of our research are environmental processes relevant for the installation of nuclear waste repositories, for remediation of uranium mining and milling sites, and for radioactive contaminations caused by nuclear accidents and fallout. Because of their high radiotoxicity and long half-life the actinides are of special interest. The research is focused on a better understanding of the chemical behavior of actinides in the environment on a molecular level. We will increase our efforts to study both the speciation of actinides on bio-molecular interfaces and their transport in bio-systems. Current topics of our research work are: aquatic chemistry of actinides, actinides in bio-systems, interaction of actinides with solid phases, Reactive transport of actinides. About 60 scientists, technicians and PhD students are employed at the Institute of Radiochemistry. We accomplished many new scientific results in the past year, which are presented in this annual report. Among them only few can be highlighted in this preface. Further progress was achieved in understanding the formation and characterization of uranium containing colloids. The newly installed method of laser-induced breakdown detection was very helpful for the identification of uranium colloids under anoxic conditions. We were very successful in the determination of formation pathways and structure of various actinide complexes. These results contribute to a better understanding of actinide speciation in geo- and bio-systems, especially with respect to the chemical processes on the interfaces. The results achieved in the characterization of the properties, modification, and interaction of the S-layers of Bacillus sphaericus with uranium and some other heavy metals strengthen our hope to use this

Forschungszentrum Rossendorf, Institute of Safety Research. Annual report 2004

International Nuclear Information System (INIS)

Weiss, F.P.; Rindelhardt, U.

2005-01-01

The Institute of Safety Research (ISR) is one of the six Research Institutes of Forschungszentrum Rossendorf e.V. (FZR e.V.) which is a member institution of the Wissenschaftsgemeinschaft Gottfried Wilhelm Leibniz (Leibniz Association). Together with the Institute of Radiochemistry, ISR constitutes the research programme ''Safety and Environment'' which is one from three scientific programmes of FZR. In the framework of this research programme, the institute is responsible for the two subprogrammes ''Plant and Reactor Safety'' and ''Thermal Fluid Dynamics'', respectively. We also provide minor contributions to the sub-programme ''Radio-Ecology''. Moreover, with the development of a pulsed photo-neutron source at the radiation source ELBE (Electron linear accelerator for beams of high brilliance and low emittance), we are involved in a networking project carried out by the FZR Institute of Nuclear and Hadron Physics, the Physics Department of TU Dresden, and ISR. (orig.)

EPOS-An intense positron beam project at the ELBE radiation source in Rossendorf

International Nuclear Information System (INIS)

Krause-Rehberg, R.; Sachert, S.; Brauer, G.; Rogov, A.; Noack, K.

2006-01-01

EPOS, the acronym of ELBE Positron Source, describes a running project to build an intense pulsed beam of mono-energetic positrons (0.2-40 keV) for materials research. Positrons will be created via pair production at a tungsten target using the pulsed 40 MeV electron beam of the superconducting linac electron linac with high brilliance and low emittance (ELBE) at Forschungszentrum Rossendorf (near Dresden, Germany). The chosen design of the system under construction is described and results of calculations simulating the interaction of the electron beam with the target are presented, and positron beam formation and transportation is also discussed

Forschungszentrum Rossendorf, Institute of Radiochemistry. Annual report 2001

International Nuclear Information System (INIS)

Fanghaenel, T.; Bernhard, G.; Engelmann, H.J.

2002-05-01

The Institute of Radiochemistry (IRC), one of the five institutes of the Forschungszentrum Rossendorf (FZR) performs basic and applied research in the fields of radiochemistry and radioecology. Main goal is the quantification of the interaction and mobility of radionuclides in the geo- and biosphere. Because of their high radiotoxicity and long half-life the actinides are of special interest. Among the actinides uranium and its manifold interactions plays a major role in the institute's research activities. In addition the interactions of some important long-lived fission and decay products are studied. More than 60 scientists, technicians and PhD students are employed in the Institute of Radiochemistry. The research is focused on understanding the fundamental processes relevant for the behavior of radionuclides in the environment. Main topics are: Aquatic chemistry, Radionuclide interaction with mineral surfaces, Radionuclide interaction with biological materials (bacteria and plants), Modeling the radionuclide transport, Development of spectroscopic speciation methods We accomplished many new scientific results in the past year, which are presented in this Annual Report. (orig.)

Accounting for and control of nuclear material at the Central Institute of Nuclear Research, Rossendorf

International Nuclear Information System (INIS)

Heidel, S.; Rossbander, W.; Helming, M.

1983-01-01

A survey is given of the system of accounting for and control of nuclear material at the Central Institute for Nuclear Research, Rossendorf. It includes 3 material balance areas. Control is implemented at both the institute and the MBA levels on the basis of concepts which are coordinated with the national control authority of the IAEA. The system applied enables national and international nuclear material control to be carried out effectively and economically at a minimum of interference with operational procedures. (author)

Forschungszentrum Rossendorf, Institute of Safety Research. Annual report 2004

Energy Technology Data Exchange (ETDEWEB)

Weiss, F.P.; Rindelhardt, U. (eds.)

2005-07-01

The Institute of Safety Research (ISR) is one of the six Research Institutes of Forschungszentrum Rossendorf e.V. (FZR e.V.) which is a member institution of the Wissenschaftsgemeinschaft Gottfried Wilhelm Leibniz (Leibniz Association). Together with the Institute of Radiochemistry, ISR constitutes the research programme ''Safety and Environment'' which is one from three scientific programmes of FZR. In the framework of this research programme, the institute is responsible for the two subprogrammes ''Plant and Reactor Safety'' and ''Thermal Fluid Dynamics'', respectively. We also provide minor contributions to the sub-programme ''Radio-Ecology''. Moreover, with the development of a pulsed photo-neutron source at the radiation source ELBE (Electron linear accelerator for beams of high brilliance and low emittance), we are involved in a networking project carried out by the FZR Institute of Nuclear and Hadron Physics, the Physics Department of TU Dresden, and ISR. (orig.)

Forschungszentrum Rossendorf. Institute of Bioinorganic and Radiopharmaceutical Chemistry. Annual report 2002

Energy Technology Data Exchange (ETDEWEB)

Johannsen, B.; Seifert, S. (eds.)

2003-01-01

In 2002 the Institute of Bioinorganic and Radiopharmaceutical Chemistry, one of five institutes in the Forschungszentrum Rossendorf e.V., continued and further developed its basic and application-oriented research. Research was focused on radiotracers as molecular probes to make the human body biochemically transparent with regard to individual molecular reactions. While further pursuing and extending our chemical, biological and medical activities in the PET Centre and being engaged in the coordination chemistry and radiopharmacology of technetium, rhenium and other metals, new lines of activity have also been opened up recently. This involves bioactive substances as they are present in food. Such substances may cause a health risk or may exert effects not yet fully understood. New biotechnological procedures in food processing also give rise to new questions that can be addressed by PET. As illustrated by the majority of contributions in this report, the Institute is predominantly engaged in radiopharmaceutical chemistry of both radiometals and the PET nuclides carbon-11 and fluorine-18. The improvement of labelling methods continued to remain an area of considerable endeavour. The review article on radiochemistry with the short-lived positron emitters {sup 11}C and {sup 18}F is meant to emphasize this field of research and to help to classify our contribution to this area. As for the radiometals, our studies agree with the more and more demanding insight that the coordination has a not sufficiently predictable impact on the in vivo behaviour of the molecule into which the chelate unit is integrated. Therefore, attempts to better understand and adjust the in vivo behaviour of the radiotracers are being continued. In order to reflect on and identify trends and perspectives, the Institute organized on March 7-8, 2002, an international conference on advances and perspectives in radiotracer development. The Institute's chemically and radiopharmacologically

Forschungszentrum Rossendorf. Institute of Bioinorganic and Radiopharmaceutical Chemistry. Annual report 2002

International Nuclear Information System (INIS)

Johannsen, B.; Seifert, S.

2003-01-01

In 2002 the Institute of Bioinorganic and Radiopharmaceutical Chemistry, one of five institutes in the Forschungszentrum Rossendorf e.V., continued and further developed its basic and application-oriented research. Research was focused on radiotracers as molecular probes to make the human body biochemically transparent with regard to individual molecular reactions. While further pursuing and extending our chemical, biological and medical activities in the PET Centre and being engaged in the coordination chemistry and radiopharmacology of technetium, rhenium and other metals, new lines of activity have also been opened up recently. This involves bioactive substances as they are present in food. Such substances may cause a health risk or may exert effects not yet fully understood. New biotechnological procedures in food processing also give rise to new questions that can be addressed by PET. As illustrated by the majority of contributions in this report, the Institute is predominantly engaged in radiopharmaceutical chemistry of both radiometals and the PET nuclides carbon-11 and fluorine-18. The improvement of labelling methods continued to remain an area of considerable endeavour. The review article on radiochemistry with the short-lived positron emitters 11 C and 18 F is meant to emphasize this field of research and to help to classify our contribution to this area. As for the radiometals, our studies agree with the more and more demanding insight that the coordination has a not sufficiently predictable impact on the in vivo behaviour of the molecule into which the chelate unit is integrated. Therefore, attempts to better understand and adjust the in vivo behaviour of the radiotracers are being continued. In order to reflect on and identify trends and perspectives, the Institute organized on March 7-8, 2002, an international conference on advances and perspectives in radiotracer development. The Institute's chemically and radiopharmacologically oriented activities

Helmholtz-Zentrum Dresden-Rossendorf, Institute of Safety Research. Annual report 2010

International Nuclear Information System (INIS)

Gerbeth, Gunter; Schaefer, Frank

2011-01-01

The Institute of Safety Research (ISR) was over the past 20 years one of the six Research Institutes of Forschungszentrum Dresden-Rossendorf e.V. (FZD), which in 2010 belonged to the Wissenschaftsgemeinschaft Gottfried Wilhelm Leibniz. Together with the Institutes of Radiochemistry and Radiation Physics, ISR implements the research programme ''Nuclear Safety Research'' (NSR), which was during last years one of the three scientific programmes of FZD. NSR involves two main topics, i.e. ''Safety Research for Radioactive Waste Disposal'' and ''Safety Research for Nuclear Reactors''. The research of ISR aims at assessing and enhancing the safety of current and future reactors, the development of advanced simulation tools including their validation against experimental data, and the development of the appropriate measuring techniques for multi-phase flows and liquid metals.

Automatically controlled facilities for irradiation of silicon crystals at the Rossendorf Research Reactor

International Nuclear Information System (INIS)

Ross, R.

1988-01-01

This report describes the facilities for neutron transmutation doping of silicon in GDR. The irradiation of silicon single crystals began at Rossendorf in 1978 with simple equipment. Only a small amount of silicon could be irradiated in it. The fast increasing need of NTD-silicon made it necessary to design and construct new and better facilities. The new facilities are capable of irradiating silicon from 2'' to 3'' in diameter. The irradiation process takes place automatically with the assistance of a computer. Material produced has an axial homogeneity of ± 7%. Irradiation riggs, techniques, irradiation control and quality control are discussed. (author). 4 figs

Perturbation measurements in reactor LR-0 and their evaluation

International Nuclear Information System (INIS)

Rypar, W.; Faehrmann, K.H.

1988-07-01

To investigate space-dependent kinetic effects in reactors of the WWER-1000 type, two central and one eccentric perturbation measurements were performed in the zero power reactor LR-0 of the UJV Rez (CSSR) by trapeze-form movements of an absorber cluster. The measurements were based ona computer aided CAMAC system for the simultaneous data acquisition of 20 spatially distributed neutron detectors and for cluster movement control. The measurements were followed by a detailed evaluation in the ZfK Rossendorf (GDR) with respect to the calculation results of flux response obtained by nodal code HEXDYN3D, the aim of which was to demostrate the limits of the point reactor model and to account for space-dependent effects by approximative methods. A sensitive check of the calculation methods was made possible especially by the eccentric perturbation where the space dependent effects,due to a larger distance of cluster movement, were most significant. (author). 17 figs., 9 refs

Helmholtz-Zentrum Dresden-Rossendorf, Institute of Safety Research. Annual report 2010

Energy Technology Data Exchange (ETDEWEB)

Gerbeth, Gunter; Schaefer, Frank (eds.)

2011-07-01

The Institute of Safety Research (ISR) was over the past 20 years one of the six Research Institutes of Forschungszentrum Dresden-Rossendorf e.V. (FZD), which in 2010 belonged to the Wissenschaftsgemeinschaft Gottfried Wilhelm Leibniz. Together with the Institutes of Radiochemistry and Radiation Physics, ISR implements the research programme ''Nuclear Safety Research'' (NSR), which was during last years one of the three scientific programmes of FZD. NSR involves two main topics, i.e. ''Safety Research for Radioactive Waste Disposal'' and ''Safety Research for Nuclear Reactors''. The research of ISR aims at assessing and enhancing the safety of current and future reactors, the development of advanced simulation tools including their validation against experimental data, and the development of the appropriate measuring techniques for multi-phase flows and liquid metals.

Monitoring and control of the Rossendorf research reactor using a microcomputerized automation system

International Nuclear Information System (INIS)

Ba weg, F.; Enkelmann, W.; Klebau, J.

1982-01-01

A decentral hierarchic information system (HIS) is presented, which has been developed for monitoring and control of the Rossendorf Research Reactor RFR, but which may also be considered the prototype of a digital automation system (AS) to be used in power stations. The functions integrated in the HIS are as follows: process monitoring, process control, and use of a specialized industrial robot for control of charging and discharging of the materials to be irradiated. The AS is realized on the basis of the process computer system PRA 30 (A 6492) developed in the GDR and including a computer K 1630 and the intelligent process terminals ursadat 5000 connected by a fast serial interface (IFLS). (author)

Forschungszentrum Rossendorf, Institute of Bioinorganic and Radiopharmaceutical Chemistry. Annual report 1995

International Nuclear Information System (INIS)

Johannsen, B.

1996-02-01

Research at the Institute of Bioinorganic and Radiopharmaceutical Chemistry of the Research Center Rossendorf is focused on radiotracers as molecular probes for diagnosis of disease. The research effort has two main components: -Positron emission tomography (PET) - technetium chemistry and radiopharmacology. The research activities of the Institute have been performed in three administratively classified groups. A PET tracer group is engaged in the chemistry and radiopharmacy of 11 C and 18 F compounds and in the setup of the PET center. A SPECT tracer group deals with the design, synthesis and chemical characterization of metal coordination compounds, primarily rhenium and technetium complexes. A biochemical group is working on SPECT and PET-relevant biochemical and biological projects. This includes the characterization and assessment of new compounds developed in the two synthetically oriented groups. The annual report presented here covers the research activities of the Institute of Bioinorganic and Radiopharmaceutical Chemistry in 1995. (orig.)

Neutron flux calculations for the Rossendorf research reactor in (hex)- and (hex,z)-geometry using SNAP-3D

International Nuclear Information System (INIS)

Koch, R.; Findeisen, A.

1986-04-01

The multigroup neutron diffusion theory code SNAP-3D has been used to perform time independent neutron flux and power calculations of the 10 MW Rossendorf research reactor of the type WWR-SM. The report describes these calculations, as well as the actual reactor configuration, some details of the code SNAP-3D, and two- and three-dimensional reactor models. For evaluating the calculations some flux values and control rod worths have been compared with those of measurements. (author)

Forschungszentrum Rossendorf, Institut fuer Ionenstrahlphysik und Materialforschung. Annual report 1993

International Nuclear Information System (INIS)

Moeller, W.; Wieser, E.; Kirch, S.

1994-04-01

Highlights were: Ion beam induced epitaxial crystallization of 6H-SiC -Band gap engineering in Co alloyed β-FeSi 2 formed by ion beam synthesis -Formation of CoSi 2 wires by maskless implantation with the focused ion beam -Phosphorus implanted n + -layers for HPGe - Development of a fluidic ISFET microsystem for chemical analysis - Depth selective Moessbauer spectroscopy of Al-implanted iron - Plasma source ion implantation - Simultaneous light element analysis by HIERD for plasma-wall interaction studies in fusion research -Paint layer studies using PIXE on air - Texture investigation on geological three phase samples - status of the Rossendorf 7.25 GHz ECR ion source -Formation of double-height Si(001) steps by sputtering with Xe ions - a computer simulation - Self-organisation during Ostwald ripening in ion beam synthesis of buried compound layers - Modification of metals and other materials - Modification of semiconductors and patterning by focused ion beam -Application of ion beams to sensors - Ion beam analysis, fundamentals of ion-solid-interaction and accelerator technique - Structural research. (orig./HP)

Beamline instrumentation and experiment automation for the Rossendorf Beamline at ESRF/Grenoble (F)

International Nuclear Information System (INIS)

Oehme, W.; Dienel, S.; Proehl, D.

2000-03-01

The Rossendorf research center finished the work (from 1996 - 1998) for building its own beamline for experiments with synchrotron radiation at the ESRF (European Synchrotron Radiation Facility) at Grenoble/France. The beamline has two measuring systems for alternative use for experiments investigating radioactive samples by means of X-ray absorption spectrometry, and materials structures by means of X-ray diffraction analyses. The report in hand focuses on work performed required for the control equipment for optical systems and performance of the measuring systems with respect to electronics, calculation methods, and software. Hardware components of importance to system instrumentation are explained, as well as the basic computing tasks and general software principles, and are illustrated with some examples. The general setting of the beamline is represented in a tabulated overview. The literature list serves as a guideline for detailed documentation. (orig./CB) [de

Forschungszentrum Rossendorf, Institute of Safety Research. Annual report 2003

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-07-01

The work of the institute is directed to the assessment and enhancement of the safety of technical plants and to the increase of the efficiency and environmental sustainability of those facilities. Subjects of investigation are equally nuclear plants and installations of process industries. To achieve the goals mentioned, the institute is mainly engaged in the scientific fields of thermal fluid dynamics including magneto-hydrodynamics (MHD) and materials sciences. In 2003, the ISR worked on the following main scientific projects. Sub-programme: Plant and Rector Safety. Project: accident analysis of nuclear reactors, safety of materials and components, particle and radiation transport, safety and efficiency of chemical processes. Sub-programme: Thermal Fluid Dynamics. Project: magneto-hydrodynamics, thermal fluid dynamics of multiphase systems. Considerable progress could also be achieved in the CFD simulation of two-phase flows. New approaches for the forces acting on steam bubbles in a water flow could be developed and implemented into the CFX code in close cooperation with the CFX developer ANSYS/CFX. The qualified models allow to simulate the evolution of bubble size specific radial void distribution profiles along the flow path. These theoretical studies and the related experiments at the Rossendorf TOPFLOW test facility represent an important part of the German CFD network that aims at the improvement of thermal hydraulic calculation methods in reactor safety. (orig.)

Forschungszentrum Rossendorf, Institute of Safety Research. Annual report 2003

International Nuclear Information System (INIS)

2004-01-01

The work of the institute is directed to the assessment and enhancement of the safety of technical plants and to the increase of the efficiency and environmental sustainability of those facilities. Subjects of investigation are equally nuclear plants and installations of process industries. To achieve the goals mentioned, the institute is mainly engaged in the scientific fields of thermal fluid dynamics including magneto-hydrodynamics (MHD) and materials sciences. In 2003, the ISR worked on the following main scientific projects. Sub-programme: Plant and Rector Safety. Project: accident analysis of nuclear reactors, safety of materials and components, particle and radiation transport, safety and efficiency of chemical processes. Sub-programme: Thermal Fluid Dynamics. Project: magneto-hydrodynamics, thermal fluid dynamics of multiphase systems. Considerable progress could also be achieved in the CFD simulation of two-phase flows. New approaches for the forces acting on steam bubbles in a water flow could be developed and implemented into the CFX code in close cooperation with the CFX developer ANSYS/CFX. The qualified models allow to simulate the evolution of bubble size specific radial void distribution profiles along the flow path. These theoretical studies and the related experiments at the Rossendorf TOPFLOW test facility represent an important part of the German CFD network that aims at the improvement of thermal hydraulic calculation methods in reactor safety. (orig.)

The modification of the Rossendorf Research Reactor

International Nuclear Information System (INIS)

Gehre, G.; Hieronymus, W.; Kampf, T.; Ringel, V.; Robbander, W.

1990-01-01

The Rossendorf Research Reactor is of the WWR-SM type. It is a heterogeneous water moderated and cooled tank reactor with a thermal power of 10 MW, which was in operation from 1957 to 1986. It was shut down in 1987 for comprehensive modifications to increase its safety and to improve the efficiency of irradiation and experimentals. The modifications will be implemented in two steps. The first one to be finished in 1989 comprises: 1) the replacement of the reactor tank and its components, the reactor cooling system, the ventilation system and the electric power installation; 2) the construction of a new reactor control room and of filtering equipment; 3) the renewal of process instrumentation and control engineering equipment for reactor operation, equipment for radiation protection monitoring, and reactor operation and safety documentation. The second step, to be implemented in the nineties, is to comprise: 1) the enlargement of the capacity for storage of spent fuel; 2) the modernization of reactor operations by computer-aided control; 3) the installation of an automated measuring systems for accident and environmental monitoring. Two objects of the modification, the replacement of the reactor tank and the design of a new and safer one as well as the increase of the redundancy of the core emergency cooling system are described in detail. For the tank replacement the exposure data are also given. Furthermore, the licensing procedures based on national ordinances and standards as well as on international standards and recommendations and the mutual responsibilities and activities of the licensing authority and of the reactor manager are presented. Finally, the present state of the modifications and the schedule up to the reactor recommissioning and test operation at full power is outlined

90Sr-90Y radionuclide generator based on ionex chromatography. Part 1 - project

International Nuclear Information System (INIS)

Miler, V.; Budsky, F.; Malek, Z.

2003-09-01

This part contains a proposal for the generator column design, materials to be used (chemicals, ionexes) and technological procedures. The proposal was inspired by the 90 Sr- 90 Y generator operated by Zfk Rossendorf. The aim was to develop and launch a generator for the preparation of carrier-free 90 Y in the form of [ 90 Y] chloride solution in dilute hydrochloric acid. The separation of Y from Sr is based on ionex chromatography by sorbing the two radionuclides on a catex. While Sr remains sorbed, 90 Y is eluted with lithium citrate. During this process, 90 Y is bonded in a citrate complex which, having a negative charge, is subsequently trapped by an anex. A guard column is inserted before the anex column to trap any traces of 90 Sr. 90 Y is eluted from the anex in the yttrium chloride form by using dilute hydrochloric acid. The product from the generator can be used for the preparation of [ 90 Y] - Fe colloid injection or [ 90 Y] - yttrium citrate injection for intra-articular application or for the development of monoclonal antibodies and peptides

'AER working group D on VVER safety analysis' minutes of the meeting in Rossendorf, Germany, 10-12 May 1999

International Nuclear Information System (INIS)

Siltanen, P.

1999-01-01

AER Working Group D on VVER reactor safety analysis held its eighth meeting in Research Centre Rossendorf during the period 10-12 May 1999. There were altogether 14 participants from eight member organizations. In addition to the general information exchange on recent activities, the topics of the meeting included: Final conclusions and lessons from the solution of the AER Dynamic Benchmark Problem No. 5 on a main steam header break accident; Validation of dynamics codes and the definition of a 6th dynamic benchmark; Safety analyses and reactivity issues: approaches and results; Advances in development of models and codes for reactor dynamics applications; Documentation of dynamic benchmark problems and solutions for the AER Benchmark Book; Future activities. (author)

Results of neutron dose measurements at the Rossendorf research reactors taking the actual neutron spectra into account

International Nuclear Information System (INIS)

Rimpler, A.; Kneschke, H.

1985-01-01

Based on a systematic evaluation of area dose studies at the beginning of the seventies, no individual routine neutron monitoring has been performed at the Rossendorf research reactors. To check this decision, a limited number of persons has been monitored with solid-state nuclear track detectors for several years. The dosemeters were calibrated on the basis of neutron spectra determined at the working places by means of the Bonner sphere method. Intermediate neutrons with a 1/E/sup α/ Fermi distribution were dominating. The fraction of fast neutrons was practically negligible. The obtained spectra, radiation, field quantities and results of individual dose measurements are presented. The dosemeter most appropriate for such neutron fields would be a 12-inch Bonner sphere rem counter. As the mean annual neutron exposure of research workers at the reactor amounted to only 2% of the maximum permissible dose, individual routine monitoring will, also in the future, not be neccessary. (author)

Forschungszentrum Rossendorf, Institute of Safety Research. Annual report 2001

International Nuclear Information System (INIS)

Weiss, F.P.; Rindelhardt, U.

2002-06-01

In the reporting period, the ISR performed 9 meetings and workshops with international participation. It is especially worth mentioning the workshop on 'Process Control and Condition Monitoring in Chemical Plants' that was conducted for the first time, and the concluding conference of the DFG Innovationskolleg 'Magneto-Hydrodynamics of Electrically Conducting Fluids'. At the ROCOM test facility (Rossendorf Coolant Mixing facility), a large series of experiments was performed dedicated to coolant mixing phenomena in PWRs during boron dilution and cold water transients. CFD models were validated against those experiments and a so called semi-analytical mixing model was developed. By coupling that semi-analytical model with the DYN3D reactor dynamics code it could be shown that a shut down reactor gets re-critical when a plug of 36 m 3 deionated water enters the core after switching on the first main coolant pump. However, that deionated plug does not lead to non-allowed high coolant pressure or fuel temperatures. The behavior of a RPV lower callotte during a severe accident with melt slumping into the lower plenum is studied in 1:10 test at Royal Institute of Technology Stockholm. At the ISR computational methods were developed for pre- and post-test calculations of those experiments in order to predict the time and mode of RPV failure. The temperature, as well as location, and time of the RPV failure were found in good agreement with the experiment. Two patents resulted from those studies. One of them proposes a creep stool to mechanically support the RPV deformed by creeping, and the flooding of the reactor pit for ex vessel cooling of the melt inside the vessel. Such measures extend the time till RPV failure and offer the possibility for additional accident management procedures that can prevent the RPV meltthrough. The MHD department of ISR was especially successful in 2001. In the framework of the Bundesministerium fuer Bildung und Forschung (BMBF) initiative

Central Institute for Nuclear Research (1956 - 1979)

International Nuclear Information System (INIS)

Flach, G.; Bonitz, M.

1979-12-01

The Central Institute for Nuclear Research (ZfK) of the Academy of Sciences of the GDR is presented. This first overall survey covers the development of the ZfK since 1956, the main research activities and results, a description of the departments responsible for the complex implementation of nuclear research, the social services for staff and the activities of different organizations in the largest central institute of the Academy of Sciences of the GDR. (author)

Forschungszentrum Rossendorf, Institute of Radiochemistry. Annual report 2000

International Nuclear Information System (INIS)

2001-05-01

The Institute of Radiochemistry (IRC), one of the five institutes of the Forschungszentrum Rossendorf (FZR) performs basic and applied research in the fields of radiochemistry and radioecology. Main goal is the quantification of the interaction and mobility of radionuclides in the geo- and biosphere. Because of their high radiotoxicity and long half-life the actinides are of special interest. Among the actinides uranium and its manifold interactions plays a major role in the institute's research activities. In addition the interactions of some important long-lived fission and decay products are studied. More than 60 scientists, technicians and PhD students are employed in the Institute of Radiochemistry. The research is focused on understanding the fundamental processes relevant for the behavior of radionuclides in the environment. Main topics are: Aquatic chemistry, Radionuclide interaction with mineral surfaces, Radionuclide interaction with biological materials (microbes and plants), Modeling the radionuclide transport, Development of spectroscopic speciation methods. Further progress was achieved in understanding the interaction mechanism of actinides with humic acids. The coordination numbers and bond distances of the coordinated oxygens have been determined by X-ray absorption spectroscopy for tetra- and pentavalent actinides (Np(IV) and Np(V)). It was shown that the carboxylic groups of the humic acid form monodentate complexes with the neptonyl ions. We extended our laser spectroscopic capabilities by installing a new laser system with ultra-short pulses (130 fs) for fluorescence measurements of organic substances. We intend to gain information on actinide complexes with organic ligands by studying the fluorescence properties of the organics with very short life times. The laser system and the method were successfully validated by the determination of the well-known uranyl-salicylic acid complexation. Although surface complexation concepts are more and more

Pulsed power magnet technology for laser particle acceleration and laser plasma physics - a survey of developments at Helmholtz-Zentrum Dresden-Rossendorf

Energy Technology Data Exchange (ETDEWEB)

Kroll, Florian; Joost, Martin [Helmholtz-Zentrum Dresden-Rossendorf (Germany); TU Dresden (Germany); Burris-Mog, Trevor; Herrmannsdoerfer, Thomas; Kraft, Stephan; Masood, Umar; Schlenvoigt, Hans-Peter; Sobiella, Manfred; Wustmann, Bernd; Zherlitsyn, Sergei; Cowan, Thomas; Schramm, Ulrich [Helmholtz-Zentrum Dresden-Rossendorf (Germany)

2013-07-01

Since the mid-1950s, pulsed high-field magnets have become a common, versatile research tool with application mostly in solid state physics and material research. Recently developed pulsed power magnet technology, specifically designed to meet the demands of laser acceleration and laser plasma experiments, open up new research opportunities: We present a pulsed air core solenoid (up to 20 T) for effective collection and focusing of laser accelerated particles. It could function as a crucial part of a compact, laser-based ion source (pursued by the LIGHT collaboration) or of beam guidance systems. Furthermore, the poster shows a split pair coil, utterly compact and with optical access in between the coil pairs and on axis, to study laser-driven plasma expansion under high magnetic fields (30 T). To power such devices, portable capacitor-based pulse generators have been developed at Helmholtz-Zentrum Dresden-Rossendorf. We present first results of the functional testing of our third-generation pulse generator. Looking forward, we outline a concept for a medical gantry based on pulsed high field beam optics.

Rossendorf Beamline at ESRF (ROBL-CRG). Bi-annual report 2009/2010

International Nuclear Information System (INIS)

Scheinost, Andreas C.; Baehtz, Carsten

2011-01-01

The Rossendorf Beamline (ROBL) - located at BM20 of the European Synchrotron Radiation Facility (ESRF) in Grenoble, France - is in operation since 1998. This 7th report covers the period from January 2009 to December 2010. In these two years, 67 peer- reviewed papers have been published based on experiments done at the beamline, more than in any biannual period before. Six highlight reports have been selected for this report to demonstrate the scientific strength and diversity of the experiments performed on the two end-stations of the beamline, dedicated to Radiochemistry (RCH) and Materials Research (MRH). The beamtime was more heavily overbooked than ever before, with an acceptance rate of only 25% experiments. We would like to thank our external proposal review members, Prof. Andre Maes (KU Leuven, Belgium), Prof. Laurent Charlet (UJF Grenoble, France), Dr. Andreas Leinweber (MPI Metallforschung, Stuttgart, Germany), Prof. David Rafaja (TU Bergakademie Freiberg, Germany), Prof. Dirk Meyer (TU Dresden, Germany), who evaluated the inhouse proposals in a thorough manner, thereby ensuring that beamtime was distributed according to scientific merit. The period was not only characterized by very successful science, but also by intense work on the optics upgrade. In spring 2009, a workshop was held at ROBL, assembling beamline experts from German, Spanish and Swiss synchrotrons, to evaluate the best setup for the new optics. These suggestions was used to prepare the call for tender published in July 2009. From the tender acceptance in November 2009 on, a series of design review meetings and factory acceptance tests followed. Already in July 2010, the first piece of equipment was delivered, the new double-crystal, double-multilayer monochromator. The disassembly of the old optics components started end of July, 2011, followed by the installation of the new components. As of December 2011, the new optics have seen the first test beam and thorough hot commissioning will

Rossendorf Beamline at ESRF (ROBL-CRG). Bi-annual report 2009/2010

Energy Technology Data Exchange (ETDEWEB)

Scheinost, Andreas C; Baehtz, Carsten [eds.

2011-07-01

The Rossendorf Beamline (ROBL) - located at BM20 of the European Synchrotron Radiation Facility (ESRF) in Grenoble, France - is in operation since 1998. This 7th report covers the period from January 2009 to December 2010. In these two years, 67 peer- reviewed papers have been published based on experiments done at the beamline, more than in any biannual period before. Six highlight reports have been selected for this report to demonstrate the scientific strength and diversity of the experiments performed on the two end-stations of the beamline, dedicated to Radiochemistry (RCH) and Materials Research (MRH). The beamtime was more heavily overbooked than ever before, with an acceptance rate of only 25% experiments. We would like to thank our external proposal review members, Prof. Andre Maes (KU Leuven, Belgium), Prof. Laurent Charlet (UJF Grenoble, France), Dr. Andreas Leinweber (MPI Metallforschung, Stuttgart, Germany), Prof. David Rafaja (TU Bergakademie Freiberg, Germany), Prof. Dirk Meyer (TU Dresden, Germany), who evaluated the inhouse proposals in a thorough manner, thereby ensuring that beamtime was distributed according to scientific merit. The period was not only characterized by very successful science, but also by intense work on the optics upgrade. In spring 2009, a workshop was held at ROBL, assembling beamline experts from German, Spanish and Swiss synchrotrons, to evaluate the best setup for the new optics. These suggestions was used to prepare the call for tender published in July 2009. From the tender acceptance in November 2009 on, a series of design review meetings and factory acceptance tests followed. Already in July 2010, the first piece of equipment was delivered, the new double-crystal, double-multilayer monochromator. The disassembly of the old optics components started end of July, 2011, followed by the installation of the new components. As of December 2011, the new optics have seen the first test beam and thorough hot commissioning will

Validation of Computational Fluid Dynamics Calculation Using Rossendorf Coolant Mixing Model Flow Measurements in Primary Loop of Coolant in a Pressurized Water Reactor Model

Directory of Open Access Journals (Sweden)

Istvan Farkas

2016-08-01

Full Text Available The aim of this work is to simulate the thermohydraulic consequences of a main steam line break and to compare the obtained results with Rossendorf Coolant Mixing Model (ROCOM 1.1 experimental results. The objective is to utilize data from steady-state mixing experiments and computational fluid dynamics (CFD calculations to determine the flow distribution and the effect of thermal mixing phenomena in the primary loops for the improvement of normal operation conditions and structural integrity assessment of pressurized water reactors. The numerical model of ROCOM was developed using the FLUENT code. The positions of the inlet and outlet boundary conditions and the distribution of detailed velocity/turbulence parameters were determined by preliminary calculations. The temperature fields of transient calculation were averaged in time and compared with time-averaged experimental data. The perforated barrel under the core inlet homogenizes the flow, and therefore, a uniform temperature distribution is formed in the pressure vessel bottom. The calculated and measured values of lowest temperature were equal. The inlet temperature is an essential parameter for safety assessment. The calculation predicts precisely the experimental results at the core inlet central region. CFD results showed a good agreement (both qualitatively and quantitatively with experimental results.

Education to a bachelor degree in the field of radiation protection in Saxony

International Nuclear Information System (INIS)

Sahre, Peter; Glaeser, Lutz; Sussek, Christian; Konschak, Klaus

2008-01-01

In Saxony like in some other countries in Germany a special mode of education to a bachelor in the field of radiation protection exists. This so called 'dual' degree consists of a theoretical part at the Universities of Cooperative Education at Riesa and Karlsruhe and a practical part at the Nuclear Engineering and Analytics Rossendorf Inc. and at the Gamma-Service Irradiation Facility Ltd. This type of education was started in Saxony in 1992 at the Rossendorf Nuclear Engineering and Analytics Inc. together with the Rossendorf Research Center, the University of Cooperative Education in Karlsruhe. Since 1996 the University of Cooperative Education Riesa received responsibility for the first two years of the science-referred study phase. The so called 'dual' degree consists of a theoretical part at the University and a practical part at the Nuclear Engineering and Analytics Rossendorf Inc. resp. Gamma-Service Irradiation Facility Ltd. and takes three years. Each three months the students change between university and on-the job-training. Up to the year 2007 the final qualification was the diploma (in German: Diplom). Now the bachelor degree is introduced. In the paper the content of the education in Riesa and Karlsruhe (theoretical part) and Rossendorf and Radeberg (practical part) is described including some titles of dissertation submitted for a diploma or bachelor thesis. Some examples of use of the bachelor at the Nuclear Engineering and Analytics Rossendorf Inc. and at the Gamma-Service Irradiation Facility Ltd. are given too. (author)

WIMS-D use by ZfK - Data input, experience, and examples

International Nuclear Information System (INIS)

Wand, H.

1983-05-01

The report provides users of the ZfK-version (EC-1055 computer) of the cell program WIMS-D with all necessary information to compile by oneself input data sets. By means of 10 examples which comprise a large number of the practically most important program options the data compilation is explained. Some experience in using special options is given. (author)

Production, control and utilization of radioisotopes including radiopharmaceuticals

International Nuclear Information System (INIS)

Muenze, R.

1985-05-01

From April 29th to May 5th, 1984 27 participants from 21 developing countries stayed within an IAEA Study Tour ('Production, Control and Utilization of Radioisotopes including Radiopharmaceuticals') in the GDR. In the CINR, Rossendorf the reactor, the cyclotron, the technological centre as well as the animal test laboratory were visited. The participants were made familiar by 10 papers with the development, production and control of radiopharmaceuticals in the CINR, Rossendorf. (author)

ROBL - a CRG beamline for radiochemistry and materials research at the ESRF

International Nuclear Information System (INIS)

Matz, W.; Schell, N.; Bernhard, G.; Claussner, J.; Oehme, W.; Prokert, F.; Reich, T.; Schlenk, R.; Proehl, D.; Funke, H.; Eichhorn, F.; Betzl, M.; Dienel, S.; Brendler, V.; Denecke, M.A.; Krug, H.; Neumann, W.; Huettig, G.; Reichel, P.; Strauch, U.

1999-04-01

The paper describes the Rossendorf Beamline (ROBL) built by the Forschungszentrum Rossendorf at th ESRF. ROBL comprises two different and independently operating experimental stations: a radiochemistry laboratory for X-ray absorption spectroscopy of non-sealed radioactive samples and a general purpose materials research station for X-ray diffraction and reflectometry mainly of thin films and interfaces modified by ion beam techniques. The radiochemistry set-up is worldwide a unique installation at a modern synchrotron radiation source. (orig.) [de

Specialized meeting on 'Current topics of reactor safety research in Germany'

International Nuclear Information System (INIS)

Kruessenberg, Anne

2013-01-01

On October 11 and 12, 2012, the 2-day specialized meeting organized by the Thermodynamics and Fluid Dynamics Group together with the Dresden-Rossendorf Helmholtz Center and TUeV NORD SysTec GmbH and Co.KG was held at the Dresden-Rossendorf Helmholtz Center within the series of events on 'Current Topics of Safety Research in Germany.' The program of lectures was supplemented by poster presentations and exhibitions by the members of the joint research groups and companies working in the fields. The meeting again was very well attended by over 100 persons. (orig.)

FZR Institute of Radiochemistry. Annual report 1991

International Nuclear Information System (INIS)

Bernhard, G.

1992-04-01

The Research Center Rossendorf Inc. was founded on 1 January 1992 as an Institute of the Blue List. It is financed in equal shares by the Free State of Saxony and the Federal Republic of Germany. The Research Center Rossendorf (FZR) carries out its scientific work in five institutes: Institute of Ion Beam Physics and Materials Research; Institute of Nuclear and Hadronic Physics; Institute of Safety Research; Institute of Bioanorganic and Radiopharmaceutical Chemistry; Institute of Radiochemistry. The presentation of the Institute of Radiochemistry is to be considered a description of working tasks from today's angle. In the course of the formation process up to the end of the year specifications and partly also substantial changes will have to be considered. Although the Research Center Rossendorf has been recently founded, its plans are based of course on the scientific experiences of its staff. The said experiences form the basis for the status report on the lines of work. The last part compiles abridged versions of individual results achieved in 1991, documenting for specialists the work done by the groups of scientists. (orig./BBR) [de

Specialized meeting on 'Current topics of reactor safety research in Germany'; Fachtag 'Aktuelle Themen der Reaktorsicherheitsforschung in Deutschland'

Energy Technology Data Exchange (ETDEWEB)

Kruessenberg, Anne

2013-04-15

On October 11 and 12, 2012, the 2-day specialized meeting organized by the Thermodynamics and Fluid Dynamics Group together with the Dresden-Rossendorf Helmholtz Center and TUeV NORD SysTec GmbH and Co.KG was held at the Dresden-Rossendorf Helmholtz Center within the series of events on 'Current Topics of Safety Research in Germany.' The program of lectures was supplemented by poster presentations and exhibitions by the members of the joint research groups and companies working in the fields. The meeting again was very well attended by over 100 persons. (orig.)

Nuclear energy research in Germany 2008. Research centers and universities

International Nuclear Information System (INIS)

Tromm, Walter

2009-01-01

This summary report presents nuclear energy research at research centers and universities in Germany in 2008. Activities are explained on the basis of examples of research projects and a description of the situation of research and teaching in general. Participants are the - Karlsruhe Research Center, - Juelich Research Center (FZJ), - Dresden-Rossendorf Research Center (FZD), - Verein fuer Kernverfahrenstechnik und Analytik Rossendorf e.V. (VKTA), - Technical University of Dresden, - University of Applied Sciences, Zittau/Goerlitz, - Institute for Nuclear Energy and Energy Systems (IKE) at the University of Stuttgart, - Reactor Simulation and Reactor Safety Working Group at the Bochum Ruhr University. (orig.)

ROSY - Rossendorf synchrotron radiation source

International Nuclear Information System (INIS)

Einfeld, D.; Matz, W.

1993-11-01

The electron energy of the storage ring will be 3 GeV and the emitted synchrotron radiation is in the hard X-ray region with a critical energy of the spectrum of E c =8,4 keV (λ c =0,14 nm). With a natural emittance of 28 π nm rad ROSY emits high brilliance radiation. Besides the radiation from bending magnets there will be the possibility for using radiation from wigglers and undulators. For the insertion devices 8 places are foreseen four of which are located in non-dispersion-free regions. The storage ring is of fourfold symmetry, has a circumference of 148 m and is designed in a modified FODO structure. An upgrade of ROSY with superconducting bending magnets in order to shift the spectrum to higher energy can easily be done. Part I contains the scientific case and a description of the planned use of the beam lines. Part II describes the design of the storage ring and its components in more detail. (orig.) [de

Clinical use of 'ROTOP-NEUROSPECT' in several brain diseases. Die klinische Anwendung von 'ROTOP-NEUROSPECT' bei verschiedenen hirnorganischen Erkrankungen

Energy Technology Data Exchange (ETDEWEB)

Wuensche, A.; Kaempfer, I.; Loessner, J.; Wagner, A.; Dietrich, J.; Strauss, I.; Neumann, G.; Otto, L.; Koegler, A.; Schenk, S.; Schneider, G. (Leipzig Univ., Klinik fuer Radiologie, Abt. Nuklearmedizin (Germany) Leipzig Univ. (Germany). Klinik fuer Neurologie Leipzig Univ. (Germany). Klinik fuer Neurochirurgie Bezirkskrankenhaus fuer Psychiatrie, Leipzig-Doesen (Germany))

1990-01-01

We proofed the suitibility of ROTOP-NEUROSPECT (R*) (HMPAO) from Rossendorf for consideration of disturbed brain circulation in 42 patients. Results we compared with morphological methods (X-ray computing tomography, angiography) and with clinical and neurological findings. We found often a disturbed brain circulation in emission computing tomography (SPECT) before morphological changes in X-ray computing tomography (CT). ROTOP-NEUROSPECT (R*) from Rossendorf is very well for consideration of disturbed brain circulation, we did not see quality differences between ROTOP-NEUROSPECT and CERETEC from Amersham. Activity accumulations in the liver and gall of both radiopharmaceuticals did not influence the test, because of the big distance to the brain. (orig.).

A shielding chamber for the Rossendorf whole body counter; Eine Abschirmkammer fuer den Rossendorfer Ganzkoerperzaehler

Energy Technology Data Exchange (ETDEWEB)

Beutmann, A.; Ebert, S.; Kaden, M.; Loehnert, D. [VKTA, Dresden (Germany); Doerfel, H.R. [IDEA System GmbH, Karlsruhe (Germany); Schreiber, W. [Ingenieurbedarf G. Schoene und W. Schreiber GmbH, Grosserkmannsdorf (Germany); Helbig, S.

2016-07-01

In connection with the relocation of the incorporation measurement point operated by the VKTA, a new shielding chamber was designed. The development of the new shielding chamber will be shown based on the design study by IDEA System and the inquiries for material availability, procurement of material and assembly technology up to fabrication, assembly and completion of the chamber. The accompanying background measurements through In-situ gamma spectrometry and first experiences with incorporation measurements at the new In-Vivo measurement facility are shown.

Radiation Safety Report 2003, Forschungszentrum Rossendorf e.V. and Verein fuer Kernverfahrenstechnik und Analytik Rossendorf e.V.; Jahresbericht Strahlenschutz 2003 des Forschungszentrums Rossendorf e.V. und des Vereins fuer Kernverfahrenstechnik und Analytik Rossendorf e.V.

Energy Technology Data Exchange (ETDEWEB)

Sahre, P. (comp.)

2004-03-01

The annual report contains information and measured data obtained with the routine monitoring and measuring activities performed in 2003 at the VKTA and the nuclear research center, FZR, referring to health physics measurements and individual dosimetry of internal and external personnel, and ambient radioactivity monitoring in the area of the two facilities. [German] Der Jahresbericht informiert ueber die Taetigkeiten und die Messwerte des Jahres 2003, die im VKTA und FZR routinemaessig durchgefuehrt und gemessen wurden in den Bereichen: 1. Personenueberwachung, berufliche Strahlenexposition von internen Mitarbeitern oder externem Personal von Fremdfirmen. 2. Strahlenschutzumgebungsueberwachung. (orig./AJ)

Radiation Safety Report 2003, Forschungszentrum Rossendorf e.V. and Verein fuer Kernverfahrenstechnik und Analytik Rossendorf e.V

International Nuclear Information System (INIS)

Sahre, P.

2004-03-01

The annual report contains information and measured data obtained with the routine monitoring and measuring activities performed in 2003 at the VKTA and the nuclear research center, FZR, referring to health physics measurements and individual dosimetry of internal and external personnel, and ambient radioactivity monitoring in the area of the two facilities [de

Abstracts of the papers presented at the workshop 'synthesis and application of radioactively labelled organic compounds'

International Nuclear Information System (INIS)

1988-10-01

The abstracts of the 12 papers read at the Rossendorf workshop comprise syntheses and radioactive labelling of organic compounds such as herbicides, steroids, peptides and others and their application as tracers, above all in kinetic studies

Workshop on a project for a FZR-beam line at ESRF

International Nuclear Information System (INIS)

Matz, W.

1993-10-01

The Research Center Rossendorf (FZR) investigates the possibilities to install its own beam line as a Cooperate Research Group-project (CRG) at the European Synchrotron Radiation Facility (ESRF) in Grenoble. The main interests for the FZR to use high brillant synchrotron radiation are in the Institute of Radiochemistry and the Institute of Ion Beam Physics and Materials Research. This workshop was organized by these two institutes together with the FZR Study group Synchrotron. The purpose of the workshop was to achieve a better understanding for the technical needs of the projected beam line for the planned research projects. Experts with experience in beam line design met with the Rossendorf groups to discuss the best layout for such a beam line. The summary of this workshop and the copies of transparencies of the lectures that were given are published in this booklet. (orig.)

Nuclear spectroscopy with lithium ions

International Nuclear Information System (INIS)

Heiser, C.

1977-02-01

A survey of the state of nuclear spectroscopy with lithium ions is given. Proceeding from the physical and nuclear properties the specific topics arising by the acceleration of these ions are discussed. The results obtained from measurements of excitation functions of different lithium reactions, particularly of compound reactions, with several target nuclei are summarized. Besides compound reactions direct reactions are important, especially transfer reactions, elastic and inelastic scattering and exchange reactions. The results on high spin states obtained by in-beam gamma-spectroscopy are discussed in detail. Finally the possibilities are considered for accelerating lithium ions in the cyclotron U-120 and in the tandem generator EGP-10 of the ZfK. (author)

Possible Intervals for T- and M-Orders of Solutions of Linear Differential Equations in the Unit Disc

Directory of Open Access Journals (Sweden)

Martin Chuaqui

2011-01-01

f(k+ak-1(zf(k-1+⋯+a1(zf′+a0(zf=0 with polynomial coefficients. In the present paper, it is shown by an example that a unit disc counterpart of such finite set does not contain all possible T- and M-orders of solutions, with respect to Nevanlinna characteristic and maximum modulus, if the coefficients are analytic functions belonging either to weighted Bergman spaces or to weighted Hardy spaces. In contrast to a finite set, possible intervals for T- and M-orders are introduced to give detailed information about the growth of solutions. Finally, these findings yield sharp lower bounds for the sums of T- and M-orders of functions in the solution bases.

Annual report 1979

International Nuclear Information System (INIS)

Muenze, R.

1979-12-01

Results obtained at the department for nuclear chemistry of the Central Institue for Nuclear Research Rossendorf are presented. Contents are the following: chemistry of nuclear fuels, reactor chemistry, isotope research, isotope production analysis, basic research, list of publications and lectures

The experimental sodium facility NAVA

International Nuclear Information System (INIS)

Langenbrunner, H.; Grunwald, G.; May, R.

1976-01-01

Within the framework of preparations for the introduction of sodium cooled fast breeder reactors an experimental sodium facility was installed at the Central Institute of Nuclear Research at Rossendorf. Design, engineering aspects and operation of this facility are described; operating experience is briefly discussed. (author)

Proceedings of the spring meeting of the Study Group for Electronic Instrumentation on April 3-5, 1995 in Juelich

International Nuclear Information System (INIS)

1995-06-01

The 17 papers presented at the meeting give a survey of recent progress in the field of electronic instrumentation of scientific and technical measuring instruments, achieved at the research centers of KFA Juelich, TU Graz, HMI Berlin, Karlsruhe FZ, and Rossendorf FZ. (DG) [de

Environmental radioactivity in the free State of Saxony. Annual report 2000

International Nuclear Information System (INIS)

2001-01-01

This annual report has been published every year since 1994. It informs on the results of monitoring as required by radiation protection laws at Rossendorf research centre and in the Sachsen sites of the WISMUT GmbH. Detailed results can be obtained from UBG. (orig.) [de

State of the art and development of radioactive material processing

International Nuclear Information System (INIS)

Muenze, R.; Hladik, O.

1981-01-01

The radioisotope production at the Rossendorf Nuclear Research Centre is reviewed, considering irradiation facilities (nuclear reactor, cyclotron), processing of activated materials, in particular of nuclear fuel after short-term irradiation and the chemical separation of fission products, and the production of sup(99m)Tc radiopharmaceuticals

Institute of Bioinorganic and Radiopharmaceutical Chemistry. Annual report 2000

International Nuclear Information System (INIS)

Johannsen, B.; Seifert, S.

2001-01-01

In 2000 the Rossendorf research centre continued and further developed its basic and application-oriented research. Research at the Institute of Bioinorganic and Radiopharmaceutical Chemistry, one of five institutes in the Research Centre, was focused on radiotracers as molecular probes to make the human body biochemically transparent with regard to individual molecular reactions. In this respect the potential for diagnostic application depends on the quality and versatility of radiopharmaceutical chemistry, which is the main discipline in our Institute. Areas in which the Institute was particularly active were the design of new radiotracers, both radiometal-based and natural organic molecules, the elaboration of radiolabelling concepts and procedures and the chemical and pharmacological evaluation of new tracers. This was complemented by more clinically oriented activities in the Positron Emission Tomography Centre Rossendorf. With numerous contributions in the fields of radiopharmaceutical chemistry, tumour agents, tumour diagnosis and brain biochemistry this Annual Report will document the scientific progress made in 2000. (orig.)

Institute of Radiochemistry. Annual report 1992

International Nuclear Information System (INIS)

Bernhard, G.

1993-05-01

The Institute for Radiochemistry of the Research Center Rossendorf Inc. (FZR) started its work on 1 January 1992. As part of the FZR the Institute of Radiochemistry (IRC) is supported by the Free State of Saxony and the Federal Republic of Germany on the basis of equal shares. Furthermore the IRC has experienced helpful support in form of additional grants. This Annual Report summerizes the research activities achieved in the first year. Some papers result from research activities done in the different divisions of radiochemistry of the former Nuclear Research Centre Rossendorf. Problems of radioecology influence the present research programme and profile of this institute. The major goal of the IRC is fundamental and applied research on the field of the transport behaviour of radiochemical pollutants in the biosphere. Owing to the fact that Saxony and Thuringia are partly contaminated from previous uranium mining activities these investigations are of actual importance. (orig./BBR)

Environmental radioactivity. Measurement and monitoring

International Nuclear Information System (INIS)

2009-11-01

The contribution on environmental radioactivity covers the following issues: natural and artificial radioactivity; continuous monitoring of radioactivity; monitoring authorities and measurement; radioactivity in the living environment; radioactivity in food and feeding stuff; radioactivity of game meat and wild-growing mushrooms; radioactivity in mines; radioactivity in the research center Rossendorf.

Environmental radioactivity. Measurement and monitoring; Umweltradioaktivitaet. Messung und Ueberwachung

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-11-15

The contribution on environmental radioactivity covers the following issues: natural and artificial radioactivity; continuous monitoring of radioactivity; monitoring authorities and measurement; radioactivity in the living environment; radioactivity in food and feeding stuff; radioactivity of game meat and wild-growing mushrooms; radioactivity in mines; radioactivity in the research center Rossendorf.

Institute of Bioinorganic and Radiopharmaceutical Chemistry. Annual report 1992

International Nuclear Information System (INIS)

Johannsen, B.

1993-04-01

The Institute of Bioinorganic and Radiopharmaceutical Chemistry of the Rossendorf Research Center (FZR) presents its 1992 anual report in order to in form on research activities in the first year of its existence. This volume contains 27 individual reports devoted to various aspects of radiotracers for nuclear medicine. (BBR)

A small and compact AMS facility for tritium depth profiling

Indian Academy of Sciences (India)

Depth profiling measurements of tritium in carbon samples have been performed during the past seven years at the AMS facility installed at the Rossendorf 3 MV Tandetron. The samples have been cut from the inner walls of the fusion experiments ASDEX-upgrade/Garching and JET/Culham. The tritium content of the ...

Radiation protection for the illegal governmental use of radiation sources. A case study

Energy Technology Data Exchange (ETDEWEB)

Becker, K.

2000-07-01

Probably for the first time, illegal governmental uses of radiation sources, including the administrative infrastructure such as special radiation protection regulation, an advisory body etc., have been documented by the evaluation of the documents of the Ministry of State Security in the former German Democratic Republic (East Germany). Over a thousand persons, but also documents, money bills etc. were marked with a wide variety of radionuclides and traced with specially developed detectors. Among the many different nuclides provided regularly from the Rossendorf Research Center near Dresden, in particular {sup 46}Sc was popular. (orig.) [German] 'Regierungskriminalitaet' kann man auch im deutschen Strahlenschutz finden. Anhand neuer Dokumentationen der so genannten Gauckbehoerden, ueber die auch schon fluechtig in der Presse berichtet und spekuliert wurde, lassen sich Einzelheiten ueber die Vorgehensweisen einfallsreicher Stasi-Mitarbeiter, die Stasi-eigene Strahlenschutzverordnung und Strahlenschutz-Kommission usw. rekonstruieren. Ueber 1.000 Personen, aber auch Gegenstaende, Dokumente, Geldscheine etc. wurden markiert, wobei unter einer Vielzahl der regelmaessig aus Rossendorf gelieferten Nukliden {sup 46}Sc besonders gern eingesetzt sowie in Dresden spezielle Nachweisgeraete entwickelt wurden. (orig.)

The Dresden 100 T/10 ms project a high magnetic field facility at an IR-FEL

CERN Document Server

Dorr, M; Eschrig, H; Fischer, F; Fulde, P; Groessinger, R; Grunberger, W; Handstein, A; Hinz, D; Kratz, R; Krug, H; Loewenhaupt, M; Müller, K H; Pobell, F; Schultz, L; Siegel, H; Steglich, F; Vergés, P

2002-01-01

Summary form only given. We have proposed to build a 100 T/10 ms, 70 T/100 ms, 60 T/1 s pulsed field user facility with a 50 MJ capacitor bank at the Forschungszentrum Rossendorf near Dresden. This would provide the appealing possibility to have access to Zeeman energies in the energy range of the infrared free-electron-lasers (5 mu m to 150 mu m; 2 ps; cw; >10 W) now under construction at the radiation source ELBE (superconducting electron linear accelerator; 40 MeV; 1 m A; 2 ps; cw) in Rossendorf. The work is accompanied by computer simulations of the planned coil systems, of the power supply, and by the development of high-strength conductors aiming at a tensile strength of about 1.5 GPa at sigma approximately= sigma /sub Cu//2 (microcomposite CuAg alloys and Cu-steel macro compounds). With a view of gaining experience in the construction and operation of pulsed magnets, a pilot pulsed field laboratory was established at the Institute of Solid State and Materials Research Dresden (IFW Dresden). The laborat...

Nuclear energy research in Germany 2009

International Nuclear Information System (INIS)

2010-01-01

Research and development (R and D) in the fields of nuclear reactor safety and safety of nuclear waste and spent fuel management in Germany are carried out at research centers and, in addition, some 32 universities. In addition, industrial research is conducted by plant vendors, and research in plant and operational safety of power plants in operation is organized by operators and by organizations of technical and scientific research and expert consultant organizations. This summary report presents nuclear energy research conducted at research centers and universities in Germany in 2009, including examples of research projects and descriptions of the situation of research and teaching. These are the organizations covered: - Hermann von Helmholtz Association of German Research Centers, - Karlsruhe Institute of Technology (KIT, responsibility of the former Karlsruhe Research Center), - Juelich Research Center (FZJ), - Nuclear Technology Competence Center East, - Dresden-Rossendorf Research Center (FZD), - Rossendorf Nuclear Process Technology and Analysis Association (VKTA), - Dresden Technical University, - Zittau/Goerlitz University of Applied Science, - Institute of Nuclear Energy and Energy Systems (IKE) of the University of Stuttgart. (orig.)

2. Workshop 'Measuring Systems for Steady-State and Transient Multiphase Flows'; 2. Workshop 'Messtechnik fuer stationaere und transiente Mehrphasenstroemungen'

Energy Technology Data Exchange (ETDEWEB)

Prasser, H.M. [ed.

1998-11-01

The 2nd Workshop on measuring systems for steady-state and transient multiphase flows was held at Rossendorf on September 24/25, 1988. 14 Papers were presented, whose subjects ranged from optical and radiometric methods to impedance sensors, hot film probes and model-assisted methods of measurement. In the field of computer simulation of multiphase flow, a trend towards 3D models was identified which makes higher demands on the spatial and time resolution and on the information volume to be acquired and processed. [German] Vom 24.-25. September 1998 fand in Rossendorf der 2. Workshop ueber Messtechnik fuer stationaere und transiente Mehrphasenstroemungen statt. Es standen 14 Vortraege auf dem Programm, das Spektrum reichte von optischen ueber radiometrische Methoden bis hin zu verschiedenen Impedanzsensoren, Heissfilmsonden und modellgestuetzten Messverfahren. Auf dem Gebiet der Computersimulation von Mehrphasenstroemungen zeichnet sich zunehmend der Uebergang zu dreidimensionalen Modellen ab. Hieraus ergeben sich neue Anforderungen an die Messtechnik, sowohl hinsichtlich der raeumlich-zeitlichen Aufloesung als auch was den Umfang der zu erfassenden Informationen betrifft. (orig./AKF)

Forschungszentrum Rossendorf, Institute of Radiochemistry. Annual report 1995

International Nuclear Information System (INIS)

Nitsche, H.

1996-02-01

The activities of the institute in the year 1995 are described by short communications. The themes of the chapters are: Speciation and migration of radionuclides; behaviour of colloids and aerosols; organic matter and their interaction with radionuclides; application of x-ray absorption spectroscopy; chemistry of heaviest elements. (SR)

Forschungszentrum Rossendorf, Institute of Radiochemistry. Annual report 1993

International Nuclear Information System (INIS)

Nitsche, H.; Bernhard, G.

1994-06-01

Since the founding of the Institute, a reorientation of the scientific direction was initiated: From the production and application of radioisotopes during the period before 1992 toward the new focus of radioecological research for risk assessment and remediation of radionuclide contaminations. The research relates to contamination problems from uranium mining in the German states of Saxony and Thuringia and in the neighboring Czech Republic, and from nuclear weapons production, testing, and accidents in the former Soviet Union. The new research direction of the Institute covers the essential aspects of radionuclide transport in the geo- and biosphere. It includes the distribution of radioactivity in ground- and surface waters and in air. We are studying the interaction of radioactive materials (a) at the interface between aqueous phase and rocks, minerals and soils, (b) the formation and distribution of colloids and aerosols, and (c) the mobilization and retardation of radionuclides through the interaction with organic contaminants and biological decay products. Our studies are essential for the successful development of environmental decontamination and remediation strategies. This report reflects the scientific transition of the Institute. The contributions to the section on ''Ecological Research'' are already focused toward the new challenge. The research that is summarized as ''General Research'' and ''Chemistry of the Heavy Elements'' clearly bear the elements of aerosol science. (orig.)

Investigation of defect structures in solids

Energy Technology Data Exchange (ETDEWEB)

Dienel, G; Hubrig, W H; Schenk, M; Syhre, H [Zentralinstitut fuer Kernforschung, Rossendorf bei Dresden (German Democratic Republic)

1976-01-01

Some central points of interest of research in the field of defect structures in solids dealt with at the Central Institute of Nuclear Research at Rossendorf in the last years are presented. Studies on f.c.c. and b.c.c. metals, radiation-induced phase transitions in perovskites and ion-implanted silicon are described in some detail.

Recalculation of measured fuel nuclide concentrations

International Nuclear Information System (INIS)

Moeller, W.

1984-01-01

The concentrations and concentration ratios of heavy fuel nuclides determined in the Central Institute for Nuclear Research Rossendorf on the basis of destructive burnup measurements are compared with the results of microburnup calculations. The possibility is discussed to improve the results by taking into account the spectral characteristics at the positions of the measuring samples. (author)

Further developments of the RES3T sorption database

International Nuclear Information System (INIS)

Brendler, V.

2002-01-01

RES 3 T - the Rossendorf expert system for surface and sorption thermodynamics currently under development has been expanded towards the provision of comprehensive sorption data sets suitable for complex natural systems of rocks and soils. Also a statistical evaluation of the available SCM (surface complexation model) data is now implemented. Finally, a normalization of SCM parameters to a standard site density has been incorporated. (orig.)

THEREDA. Thermodynamic reference data base. Phase II. Release of thermodynamic data. Summary and final report; THEREDA. Thermodynamische Referenz-Datenbasis. Phase II. Freigabe thermodynamischer Daten. Zusammenfassung der Abschlussberichte

Energy Technology Data Exchange (ETDEWEB)

Altmaier, Marcus; Gaona, Xavier; Marquardt, Christian; Montoya, Vanessa [Karlsruher Institut fuer Technologie (KIT), Eggenstein-Leopoldshafen (Germany). Institut fuer Nukleare Entsorgung; Bok, Frank; Richter, Anke [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Inst. of Resource Ecology; Moog, Helge C.; Scharge, Tina [Gesellschaft fuer Anlagen- und Reaktorsicherheit mbH (GRS), Koeln (Germany); Voigt, Wolfgang [Technische Univ. Bergakademie Freiberg (Germany); Wilhelm, Stefan [AF Consult AG, Baden-Daettwil (Switzerland)

2015-12-15

The final report on the thermodynamic reference data base THEREDA covers the following issues: project management, quality management (Helmholtz-Zentrum Dresden-Rossendorf HZDR and GRS), data base interfaces, documentation, uranium (HZDR), other nuclides (Karlsruhe Institute for technology, KIT), data for cement minerals and their reaction products (AF-Consult, GRS), phosphate (GRS), systems with CO2 and carbonate at variable temperatures and pressure (Bergakademie Freiberg, TUBAF).

Comparison of rod-ejection transient calculations in hexagonal-Z geometry

International Nuclear Information System (INIS)

Knight, M.P.; Brohan, P.; Finnemann, H.; Huesken, J.

1995-01-01

This paper proposes a set of 3-dimensional benchmark rod ejection problems for a VVER reactor, based on the well-known NEACRP PWR rod-ejection problems defined by Siemens/KWU. Predictions for these benchmarks derived using three hexagonal-z nodal transient codes, the PANTHER code of Nuclear Electric, the HEXTIME code of Siemens/KWU, and the DYN3D code of FZ-Rossendorf are presented and compared

Project of a test stand for cyclotron ion sources

International Nuclear Information System (INIS)

Buettig, H.; Dietrich, J.; Merker, H.; Odrich, H.; Preusche, S.; Weissig, J.

1978-10-01

In the work the construction of a test stand for testing and optimization of ion sources of the Rossendorf cyclotron U-120 is represented. The design procedure and the construction of the electromagnet, the vacuum chamber with monant, the vacuum system, the power supply and the detecting system are demonstrated. The results of calculations of the motion of ions in the magnetic field are presented. (author)

Central Institute of Nuclear Research Rossendorf 25 years old

International Nuclear Information System (INIS)

Hohmuth, K.; Kaun, K.H.; Schmidt, A.; Hennig, K.; Brinckmann, H.F.; Lehmann, E.; Rossbander, W.; Bitterlich, H.; Weibrecht, R.; Fuelle, R.; Nebel, D.; Reetz, T.; Beyer, G.J.; Muenze, R.

1981-12-01

A colloquium dedicated the 25th anniversary of the foundation of the Central Institute for Nuclear Research of the GDR Academy of Sciences was held on January, 21st, '81. 13 papers were given which dealt with aspects of the institute's history as well as with modern trends in nuclear and solid state physics, nuclear energy and chemistry, radioisotope production, radiation protection and nuclear information. (author)

Forschungszentrum Rossendorf, Institute of Safety Research. Annual report 1997

Energy Technology Data Exchange (ETDEWEB)

Weiss, F P; Rindelhardt, U [eds.

1998-10-01

The research work of the institute aims at the assessment and increase of the safety of technical facilities. Subject of the investigation are equally nuclear plants and installations of process industries. To analyse thermo-fluiddynamic phenomena of accident scenarios physical models and computer codes are developed as well for multi-phase and multi-component flows as for the time and space dependent power release (neutron kinetics in light water reactors, reaction kinetics of exothermic chemical reactions). Emphasis is put on the description of spatial flows and the transient evolution of flow patterns. (orig.)

Forschungszentrum Rossendorf, Institute of Safety Research. Annual report 1999

International Nuclear Information System (INIS)

Weiss, F.P.; Rindelhardt, U.

2000-02-01

The work of the institute is directed to the assessment and enhancement of the safety of large technical plants and to the increase of the effectiveness and environmental sustainability of those facilities. Subjects of investigations are equally nuclear plants and installations of process industries. To achieve the above mentioned goals, the institute is engaged in two scientific fields, i.e. thermo-fluiddynamics including magneto-hydrodynamics (MHD) and materials/components safety. (orig.)

Forschungszentrum Rossendorf, Institute of Safety Research. Annual report 1996

International Nuclear Information System (INIS)

Weiss, F.P.; Rindelhardt, U.

1997-08-01

The research of the institute aims at the safety assessment of the design of nuclear and chemical facilities, the development of accident management procedures, and the increase of operational safety by improved plant surveillance. Physical models and computer codes are developed for multiphase/multicomponent flows and for the space and time dependent power release in nuclear and chemical reactors to be able to analyse the thermo-fluiddynamic phenomena during assumed accident scenarios. Emphasis is particularly focussed on spatial flow phenomena and the time dependent change of flow patterns. Sustainable void fraction probes and tomographic systems are developed to measure those parameters of two phase flows that characterize the exchange of pulse, energy and mass between the phases and components. The research related to materials safety is directed to the behaviour of components exposed to neutron and gamma radiation. The susceptibility to irradiation induced embrittlement and the behaviour of annealed material during reirradiation are investigated by fracture mechanical methods in dependence on the materials composition. The work on process and plant diagnostics makes available basic methods for early failure detection and operational monitoring which are important means of accident prevention. Recent initiatives of the institute are concerned with the transport of pollutants in the geosphere. Particularly, codes are developed for the simulation of physical and chemical processes during the transport of pollutants in unsaturated zones of the soil. (orig.)

Forschungszentrum Rossendorf, Institute of Safety Research. Annual report 1996

Energy Technology Data Exchange (ETDEWEB)

Weiss, F P; Rindelhardt, U [eds.

1997-08-01

The research of the institute aims at the safety assessment of the design of nuclear and chemical facilities, the development of accident management procedures, and the increase of operational safety by improved plant surveillance. Physical models and computer codes are developed for multiphase/multicomponent flows and for the space and time dependent power release in nuclear and chemical reactors to be able to analyse the thermo-fluiddynamic phenomena during assumed accident scenarios. Emphasis is particulary focussed on spatial flow phenomena and the time dependent change of flow patterns. Sustainable void fraction probes and tomographic systems are developed to measure those parameters of two phase flows that characterize the exchange of pulse, energy and mass between the phases and components. The research related to materials safety is directed to the behaviour of components exposed to neutron and gamma radiation. The susceptibility to irradiation induced embrittlement and the behaviour of annealed material during reirradiation are investigated by fracture mechanical methods in dependence on the materials composition. The work on process and plant diagnostics makes available basic methods for early failure detection and operational monitoring which are important means of accident prevention. Recent initiatives of the institute are concerned with the transport of pollutants in the geosphere. Particularly, codes are developed for the simulation of physical and chemical processes during the transport of pollutants in unsaturated zones of the soil. (orig.)

Forschungszentrum Rossendorf, Institute for Safety Research. Annual report 1994

International Nuclear Information System (INIS)

Weiss, F.P.; Rindelhardt, U.

1995-06-01

Striving for the assessment and enhancement of design based safety, for improving operational safety, and for risk management IFS is engaged in the following methodical fields: - Experimental and theoretical thermo-fluiddynamics, - 3-dimensional neutron kinetics, - characterization of the mechanical behaviour of aged materials and microstructural analysis, -transport calculations of particle and radiation fields, - early failure diagnostics of processes and plants, - hazard ranking of non-nuclear waste deposits and support of the selection of appropriate remediation procedures by means of decision analysis. In 1994, special efforts were directed to the extension of experimental facilities needed for radioactive materials testing and for two phase flow investigations. Moreover, first research projects on the safety of VVER reactors could successfully be finished. (orig./HP)

Forschungszentrum Rossendorf, Institute for Safety Research. Annual report 1995

International Nuclear Information System (INIS)

Weiss, F.P.; Rindelhardt, U.

1996-09-01

The scientific work of the Institute of Safety Research covers a wide range of safety related investigations. During 1995 important results on thermo-fluid dynamic single effects, thermalhydraulics and neutron kinetics for accident analysis, materials safety, simulation of radiation and particle transport, mechanical integrity of technical systems and process monitoring, risk management for waste deposits, magneto-hydrodynamics of conductive fluids, and of renewable energies were reached. The annual report presents also lists of publications, conference contributions, meetings, and workshops. (DG)

A shielding chamber for the Rossendorf whole body counter

International Nuclear Information System (INIS)

Beutmann, A.; Ebert, S.; Kaden, M.; Loehnert, D.; Doerfel, H.R.; Schreiber, W.; Helbig, S.

2016-01-01

In connection with the relocation of the incorporation measurement point operated by the VKTA, a new shielding chamber was designed. The development of the new shielding chamber will be shown based on the design study by IDEA System and the inquiries for material availability, procurement of material and assembly technology up to fabrication, assembly and completion of the chamber. The accompanying background measurements through In-situ gamma spectrometry and first experiences with incorporation measurements at the new In-Vivo measurement facility are shown.

Forschungszentrum Rossendorf, Institute for Safety Research. Annual report 1993

International Nuclear Information System (INIS)

Weiss, F.P.; Rindelhardt, U.

1994-06-01

Seven of the 10 selected reports describe computer codes for the analysis of accident scenarios at the Russian VVER type reactors, irradiation induced defect structures, neutron fluence calculations, acoustic leak detection using neural networks, diagnostics and modelling of component vibration of VVER reactors, and a specification of a technical system to improve the operational monitoring of Zaporoche-5 reactor. The other 3 reports show a computer simulation of a plasma source, an decision analysis for the assessment of risks with conventional and radioactive wastes, and investigations on renewable energy systems. (DG)

Safety in pipeline systems. Prevention of pressure shocks and cavitation shocks; Sichere Rohrleitungssysteme. Vermeidung von Druckstoessen und Kavitationsschlaegen

Energy Technology Data Exchange (ETDEWEB)

Prasser, H.-M. [Forschungszentrum Rossendorf, Dresden (Germany); Dudlik, Andreas; Schoenfeld, Sri Budi Handajani; Apostolidis, Alexander; Schlueter, Stefan [Fraunhofer-Institut UMSICHT, Oberhausen (Germany)

2002-06-01

The Fraunhofer institute UMSICHT, Oberhausen, and Rossendorf research centre FZR investigated the causes and consequences of pressure shocks and cavitation shocks and ways to prevent them. The experimental set-up and software tools were made available. New methods for preventing pressure shocks and cavitation shocks were developed, and armatures were developed on this basis which are also suited for retrofitting. [German] In Rohrleitungssystemen koennen durch instationaere Stroemungsvorgaenge gefaehrliche Betriebsbedingungen entstehen, die infolge von mehrfach erhoehtem Systemdruck und von Lasteintraegen in Halterungen Mensch und Umwelt erheblich schaedigen. Je nach Industriebranche koennen unterschiedliche betriebsbedingte Ursachen zu sog. Druckstoessen, Kavitations- und Kondensationsschlaegen fuehren, z.B. Kontaktkondensation von Dampf und Wasser oder ploetzliche Aenderung der Fluessigkeitsgeschwindigkeit. Das Fraunhofer-Institut UMSICHT in Oberhausen und das Forschungszentrum Rossendorf FZR untersuchen Ursachen, Folgen und Moeglichkeiten zur Vermeidung von Druckstoessen und Kavitationsschlaegen. Hierzu stehen Versuchsanlagen unterschiedlichen Massstabs sowie Softwaretools zur Verfuegung. Aus den Forschungsergebnissen wurden neue Methoden zur Vermeidung von Druckstoessen und Kavitationsschlaegen entwickelt. Hierbei werden neue oder vorhandene Absperrarmaturen mit einem hydraulischen Bremssystem ausgeruestet und mit einer Rueckschlagklappe kombiniert angeordnet. Das System gilt auch fuer bereits existierende Anlagen als besonders geeignet, da es keine Hilfsenergie benoetigt und sich an Aenderungen der Systemparameter Druck und Fliessgeschwindigkeit selbststaendig anpasst. (orig.)

First results with the novel petawatt laser acceleration facility in Dresden

International Nuclear Information System (INIS)

Schramm, U; Bussmann, M; Irman, A; Siebold, M; Zeil, K; Albach, D; Bernert, C; Bock, S; Brack, F; Branco, J; Couperus, JP; Cowan, TE; Debus, A; Eisenmann, C; Garten, M; Gebhardt, R; Grams, S; Helbig, U; Huebl, A; Kluge, T

2017-01-01

We report on first commissioning results of the DRACO Petawatt ultra-short pulse laser system implemented at the ELBE center for high power radiation sources of Helmholtz-Zentrum Dresden-Rossendorf. Key parameters of the laser system essential for efficient and reproducible performance of plasma accelerators are presented and discussed with the demonstration of 40 MeV proton acceleration under TNSA conditions as well as peaked electron spectra with unprecedented bunch charge in the 0.5 nC range. (paper)

48{sup th} Annual meeting on nuclear technology (AMNT 2017). Workshop: Preserving competence in nuclear technology

Energy Technology Data Exchange (ETDEWEB)

Steinwarz, Wolfgang

2017-10-15

On the 19{sup th} workshop ''Preserving Competence in Nuclear Technology'' 17 young scientists presented the results from their thesis work for a diploma, mastership or a PhD covering a broad spectrum of technical areas. This demonstrated again the strong engagement of the younger generation for the nuclear technology and the significant support by the involved German institutions. The jury awarded Thomas Schaefer (Helmholtz-Zentrum Dresden- Rossendorf) with the Siempelkamp Competence Price 2017.

Rossendorf Research Center, Institute of Safety Research. Annual report 1991

International Nuclear Information System (INIS)

Boehmert, J.; Weiss, F.P.

1992-08-01

The working program covers above all topics concerning the assessment of design basis safety and the increase of operational safety of the WWER type reactors. The topics are directed to the WWER-440/213 type and to the WWER-1000 type, and are dealt with by the three departments, i.e. incident analysis, neutron embrittlement, and mechanical integrity. One paper is concerned with the determination of the neutron field of HERA. (orig.) [de

Severe accident research activities at Helmholtz-Zentrum Dresden-Rossendorf (HZDR)

Energy Technology Data Exchange (ETDEWEB)

Wilhelm, Polina; Jobst, Matthias; Schaefer, Frank; Kliem, Soeren [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany)

2016-05-15

In the frame of the nuclear safety research program of the Helmholtz Association HZDR performs fundamental and applied research to assess and to reduce the risks related to the nuclear fuel cycle and the production of electricity in nuclear power plants. One of the research topics focuses on the safety aspects of current and future reactor designs. This includes the development and application of methods for analyses of transients and postulated accidents, covering the whole spectrum from normal operation till severe accident sequences including core degradation. This paper gives an overview of the severe accident research activities at the Reactor Safety Division at the Institute of Resource Ecology.

Verein fuer Kernverfahrenstechnik und Analytik Rossendorf (VKTA). Annual report 1995

International Nuclear Information System (INIS)

Haefele, W.

1996-04-01

The annual report 1995 presents information from the managing and financial departments and on the activities and achievements of the scientific-technical departments relating to nuclear facilities, radioactive waste management, radioactivity analytics, measurement and management of radioactivity in the environment, radiopharmaceuticals, and safety and radiological protection. The main activities continued to be the management of radwaste resulting from decommissioning of the research reactors and facilities on site; other activities include cooperative activities together with the Siemens company assisting in erection and establishment of isotope production labs in developing countries. There also is an organizational chart of the institution. (DG) [de

Inelastic scattering of fast neutrons on Fe-56; Inelastische Streuung schneller Neutronen an {sup 56}Fe

Energy Technology Data Exchange (ETDEWEB)

Beyer, Roland

2014-11-24

The relevant reaction cross sections for the nuclear transmutation will be measured at the neutron flight time facility nELBE in Dresden-Rossendorf. Transmutation by fast neutron irradiation is supposed to reduce the radiotoxicity of high-level radioactive wastes. The thesis is aimed to measure the inelastic neutron scattering cross sections of Fe-56 using a new double flight-time method. With combined plastic and BaF2 scintillation detectors for the first time the emitted neutrons and photons are observed in coincidence.

Institute of Bioinorganic and Radiopharmaceutical Chemistry. Annual report 2001

International Nuclear Information System (INIS)

Johannsen, B.; Seifert, S.

2002-01-01

In 2001 the Forschungszentrum Rossendorf e.V. continued and further developed its basic and application-oriented research. Research at the Institute of Bioinorganic and Radiopharmaceutical Chemistry, one of five institutes in the Research Centre, was focused on radiotracers as molecular probes to make the human body biochemically transparent with regard to individual molecular reactions. As illustrated by the large number of contributions in this report, the Institute is predominantly engaged in the coordination chemistry and radiopharmacology of technetium and rhenium. (orig.)

3D neutronic codes coupled with thermal-hydraulic system codes for PWR, and BWR and VVER reactors

Energy Technology Data Exchange (ETDEWEB)

Langenbuch, S.; Velkov, K. [GRS, Garching (Germany); Lizorkin, M. [Kurchatov-Institute, Moscow (Russian Federation)] [and others

1997-07-01

This paper describes the objectives of code development for coupling 3D neutronics codes with thermal-hydraulic system codes. The present status of coupling ATHLET with three 3D neutronics codes for VVER- and LWR-reactors is presented. After describing the basic features of the 3D neutronic codes BIPR-8 from Kurchatov-Institute, DYN3D from Research Center Rossendorf and QUABOX/CUBBOX from GRS, first applications of coupled codes for different transient and accident scenarios are presented. The need of further investigations is discussed.

Construction and use of an intense positron source at new linac facilities in Germany. Conceptual report

International Nuclear Information System (INIS)

Brauer, G.

2000-07-01

In this conceptual report the idea to establish an European positron source for applied research (''EPOS'') based on new LINAC facilities in Germany (ELBE/Rossendorf or TTF-DESY/Hamburg) is considered. The report contains not only the outline of obvious applications in atomic physics, materials science and surface physics, but also several new methodical developments which are only possible with an intense positron beam. This opportunity will also allow the use and further development of imaging techniques being of special interest for industrial applications. (orig.)

Method of allowing for resonances in calculating reactivity values

International Nuclear Information System (INIS)

Kumpf, H.

1985-01-01

On the basis of the integral transport equation for the source density an expression has been derived for calculating reactivity values taking resonances in the core and in the sample into account. The model has been used for evaluating reactivities measured in the Rossendorf SEG IV configuration. It is shown that the influence of resonances in the core can be kept tolerable, if a sufficiently thick buffer zone of only slightly absorbing non-resonant material is arranged between the sample and the core. (author)

Forschungszentrum Rossendorf, Institute of Nuclear and Hadronic Physics. Annual report 1993

International Nuclear Information System (INIS)

Doenau, F.; Prade, H.

1994-03-01

The theoretical investigations performed in 1993 dealt with the study of nuclear and subnuclear degrees of freedom, high-spin phenomena and the dynamics of open quantum systems. The results of the research and developments are presented in numerous publications, conference contributions and talks. Experimental data are obtained from in-beam spectroscopic studies, medium energy physics and heavy ion physics. The participation in national or international research projects has been continued. (orig.)

1989 annual report of the Rossendorf Central Institute of Nuclear Research

International Nuclear Information System (INIS)

Fromm, W.; Kaun, K.H.; Moeller, K.; Naehring, F.; Schulz, H.; Winter, G.; Heidel, I.; Breiter, S.

1990-01-01

The research and development results are classified by research lines. Each section starts with an introduction summing up the developments of the particular field of work, followed by progress reports on specific projects, contributions on partial results not published so far, and summaries of 1989 publications. Research priorities are, among others, the fields of nuclear spectroscopy; ion-beam solid state physics; positron emission tomography; nuclear trace technology; neutron doping, and accelerator development. (DG) [de

Annual report 1994 of the Verein fuer Kernverfahrenstechnik und Analytik, Rossendorf

International Nuclear Information System (INIS)

Haefele, W.

1995-05-01

The annual report 1994 of the VKTA presents reports on the scientific and technical activities and the management activities, and an organigram. The scientific-technical activities focus on the subjects of nuclear facilities, nuclear waste management, radioactivity monitoring and analysis, site decontamination and rehabilititation, radiopharmaceuticals, and safety and radiological protection. (DG) [de

Response of multi-strip multi-gap resistive plate chamber using pulsed electron beam

International Nuclear Information System (INIS)

Datta Pramanik, U.; Chakraborty, S.; Rahaman, A.; Ray, J.; Chatterjee, S.; Bemmerer, D.; Elekes, Z.; Kempe, M.; Sobiella, M.; Stach, D.; Wagner, A.; Yakorev, D.; Leifels, Y.; Simon, H.

2011-01-01

A prototype of Multi-strip Multi-gap Resistive Plate Chamber (MMRPC) with active area 40 cm x 20 cm has been developed at SINP, Kolkata. Electron response of the developed detector was studied using the electron linac ELBE at Forschungszentrum Dresden-Rossendorf. The development of this detector started with the aim of developing a neutron detector but this ultrafast timing detector can be used efficiently for the purpose of medical imaging, security purpose and detection of minimum ionising particle. In this article detailed analysis of electron response to our developed MMRPC will be presented

Radiation protection for the illegal governmental use of radiation sources. A case study

International Nuclear Information System (INIS)

Becker, K.

2000-01-01

Probably for the first time, illegal governmental uses of radiation sources, including the administrative infrastructure such as special radiation protection regulation, an advisory body etc., have been documented by the evaluation of the documents of the Ministry of State Security in the former German Democratic Republic (East Germany). Over a thousand persons, but also documents, money bills etc. were marked with a wide variety of radionuclides and traced with specially developed detectors. Among the many different nuclides provided regularly from the Rossendorf Research Center near Dresden, in particular 46 Sc was popular. (orig.) [de

X-ray photoelectron spectroscopy of HUPA organic substances: natural and synthetic humic compounds

International Nuclear Information System (INIS)

Barre, N.; Mercier-Bion, F.; Reiller, P.

2004-01-01

X-ray photoelectron spectroscopy (XPS) results on the characterisation of the HUPA organic materials, i.e. natural humic substances ''GOHY 573'' (fulvic acid FA and humic acid HA) extracted from the Gorleben ground waters, and synthetic humic acids ''M1'' and ''M42'' obtained from a standard melanoidin preparation from FZ Rossendorf, are presented in this paper. XPS investigations were focused on the determination of the chemical environment of the major elements as carbon, nitrogen, oxygen and sulphur, and on the identification of trace metals trapped by these organic compounds. (orig.)

CFD simulation of a particle loaded coolant flow in the sump and in the condensation chamber; Entwicklung von CFD-Modellen fuer Wandsieden und Entwicklung hchaufloesender, schneller Roentgentomographie fuer die Analyse von Zweiphasenstroemungen in Brennstabbuendeln

Energy Technology Data Exchange (ETDEWEB)

Krepper, Eckhard; Rzehak, Roland; Barthel, Frank; Franz, Ronald; Hampel, Uwe

2013-07-01

A collaborative project funded by the BMBF in the framework of the R and D program ''Energie 2020+'' by 4 Universities, 2 Research Centres and ANSYS was coordinated by Helmholtz- Zentrum Dresden-Rossendorf (HZDR). The present report describes the contributions of HZDR done from September 2009 to January 2013. The project was directed towards the development and validation of CFD models of boiling processes in PWR in the range from subcooled nucleate boiling up to the critical heat flux. The report describes the developed and used models. Main achievements were a comprehensive study of the boiling process itself and a better description of the interfacial area by coupling of wall boiling with a population balance model. The model extensions are validated and the present capabilities of CFD for wall boiling are investigated. By means of rod bundle experiments was shown that the measured cross sectional averaged values can be reproduced well with a single set of calibrated model parameters for different tests cases. For the reproduction of patterns of void distribution cross sections attention has to be focussed on the modelling of turbulence in the narrow channel. The experimental work was focussed on the investigation of the flow in a rod bundle. Using a rod bundle test rig the turbulent single phase flow field (PIV) and the average gas volume fraction (gamma densitometry) are measured. The timely and spatial resolved gas fraction was measured applying the ''High speed x-ray tomography'', developed in Rossendorf.

Man-machine communication in reactor control using AI methods

International Nuclear Information System (INIS)

Klebau, J.; Lindner, A.; Fiedler, U.

1987-01-01

In the last years the interest in process control has expecially focused on problems of man-machine communication. It depends on its great importance to process performance and user acceptance. Advanced computerized operator aids, e.g. in nuclear power plants, are as well as their man-machine interface. In the Central Institute for Nuclear Research in Rossendorf a computerized operator support system for nuclear power plants is designed, which is involved in a decentralized process automation system. A similar but simpler system, the Hierarchical Informational System (HIS) at the Rossendorf Research Reactor, works with a computer controlled man-machine interface, based on menu. In the special case of the disturbance analysis program SAAP-2, which is included in the HIS, the limits of menu techniques are obviously. Therefore it seems to be necessary and with extended hard- and software possible to realize an user controlled natural language interface using Artificial Intelligence (AI) methods. The draft of such a system is described. It should be able to learn during a teaching phase all phrases and their meanings. The system will work on the basis of a self-organizing, associative data structure. It is used to recognize a great amount of words which are used in language analysis. Error recognition and, if possible, correction is done by means of a distance function in the word set. Language analysis should be carried out with a simplified word class controlled functional analysis. With this interface it is supposed to get experience in intelligent man-machine communication to enhance operational safety in future. (author)

Manual for operation of the multipurpose thermalhydraulic test facility TOPFLOW (Transient Two Phase Flow Test Facility)

International Nuclear Information System (INIS)

Beyer, M.; Carl, H.; Schuetz, H.; Pietruske, H.; Lenk, S.

2004-07-01

The Forschungszentrum Rossendorf (FZR) e. V. is constructing a new large-scale test facility, TOPFLOW, for thermalhydraulic single effect tests. The acronym stands for transient two phase flow test facility. It will mainly be used for the investigation of generic and applied steady state and transient two phase flow phenomena and the development and validation of models of computational fluid dynamic (CFD) codes. The manual of the test facility must always be available for the staff in the control room and is restricted condition during operation of personnel and also reconstruction of the facility. (orig./GL)

Thermophysical, Electrical, and Optical Properties of Selected Metal-Nonmetal Transition Materials: Comprehensive Bibliography with Typical Data.

Science.gov (United States)

1978-02-01

Brueckner, G., " Positron Annihilation in Vanadium(IV) Oxide and Vanadium(III) Oxide," Zentralinst. Kernforsch., Rossendorf, Dresden, ZEK-295, 93-4, 1975...Phys.-Solid State, 17(5), 851-5, 1975. A000130. Andreeff, A. and Brauer, G., " Positron Annihilation Study of the Metal- Insulator Transition in V20 3...thermal expansion at 298 K. Sample N o. a TH l Mkta1 l c phase X - 0 . 0 0 20.2 0.3 - b6 . 0.3 0.04 TI 24.4 -5.6 4-moleli Mgo 25.5 2.0 -9.5 * 2.0 16

ELBE Center for High-Power Radiation Sources

Directory of Open Access Journals (Sweden)

Peter Dr. Michel

2016-01-01

Full Text Available In the ELBE Center for High-Power Radiation Sources, the superconducting linear electron accelerator ELBE, serving  two free electron lasers, sources for intense coherent THz radiation, mono-energetic positrons, electrons, γ-rays, a neutron time-of-flight system as well as two synchronized ultra-short pulsed Petawatt laser systems are collocated. The characteristics of these beams make the ELBE center a unique research instrument for a variety of external users in fields ranging from material science over nuclear physics to cancer research, as well as scientists of the Helmholtz-Zentrum Dresden-Rossendorf (HZDR.

Test measurement of a new TESLA cavity beam position monitor at the ELBE linac

International Nuclear Information System (INIS)

Sargsyan, V.; Schreiber, H.J.; Evtushenko, P.; Schurig, R.

2004-01-01

A new type of a cavity BPM proposed for beam position determination along the TESLA linac was tested at the accelerator ELBE in Rossendorf / Dresden. Measurements using an improved BPM (large and stable cross-talk isolation, significantly less energy dissipation, a novel LO signal generation) were performed in single- and multi-bunch regimes. Agreement with expectations was found. The low bunch charge available allowed for preliminary measurements on sensitivity and position resolution, which extrapolated to TESLA would ful l the demands for precise bunch-to-bunch position determination. Possible improvements, in particular on the signal processing scheme, are also discussed. (orig.)

The treatment of uranyl nitrate from the AMOR process for VKTA Rossendorf

International Nuclear Information System (INIS)

Boessert, W.; Krempl, R.; Miller, J.W.

2003-01-01

The blending of uranyl nitrate solutions at VKTA and its subsequent treatment at BNFL-Sellafield is a significant step towards the safe and effective treatment of these enriched uranyl nitrate solutions. Overall the integration of the expertise of the international company BNFL/Westinghouse will lead to the achievement of a successful solution. This success has involved the integration of the project management and operational facilities of BNFL Sellafield with the local planning, design and manufacture capacities of Westinghouse Reaktor GmbH. (orig.)

Annual report 1993 by the Rossendorf Society of Nuclear Engineering and Analysis

International Nuclear Information System (INIS)

Haefele, W.

1994-03-01

The second annual report contains, apart from the business report and the organigram, priorities and results achieved in the special fields of nuclear installations (decommissioning and disposal), nuclear waste management (radioactive wastes), nuclear analyses and rehabilitation, radiopharmaceuticals, and safety and radiation protection. (HP) [de

Free release of the premises of a company according to the ''De.Minimis Concept'' - an application from the point of view of the operator and the consultant

International Nuclear Information System (INIS)

Knappik, R.; Schmidt, G.

2003-01-01

VKTA are carrying out for the Free State of Saxony the decommissioning of nuclear facilities at the Rossendorf Research Site at Dresden as well as the related tasks for waste management and free release. Therefore, concepts need to be developed of how the optimum method towards greenfield should be designed in each individual case taking into consideration the specific characteristics of the site. The facilities for waste management and storage that have been installed on part of the VKTA area and which to a large extend are below surface level have been decommissioned and the sources of contamination removed. Parts of buildings, surfaces and deeper soil layers are partly contaminated with radioactive substances. It is the final objective to free release these premises from the ambit of the Atomic Energy Act. In such a case the remaining buildings are completely removed (Method 1) which is accompanied by large-scale earth moving to remove soil contaminations for subsequent free release. In this case VKTA considers it the more intelligent and less costly solution to free release the remaining building structures and the surrounding soil on the basis of the de-minimise concept (Method 2). Taking into consideration ancillary conditions, in particular the future uses of the area and being aware of the results of the hydrogeological opinion for the Rossendorf Site, the history of the facilities and the large number of analyzed soil samples, the 10-μSv/a concept may be complied with also for the case that deeper contaminations and the remaining building structures remain in the soil. Therefore, the operator and the expert consultant will present the problem from their points of view. (orig.)

Data compilation and evaluation of U(IV) and U(VI) for thermodynamic reference database THEREDA

Energy Technology Data Exchange (ETDEWEB)

Richter, Anke; Bok, Frank; Brendler, Vinzenz

2015-07-01

THEREDA (Thermodynamic Reference Database) is a collaborative project, which has been addressed this challenge. The partners are Helmholtz-Zentrum Dresden-Rossendorf, Karlsruhe Institute of Technology (KIT-INE), Gesellschaft fuer Anlagen- und Reaktorsicherheit Braunschweig mbH (GRS), TU Bergakademie Freiberg (TUBAF) and AF-Consult Switzerland AG (Baden, Switzerland). The aim of the project is the establishment of a consistent and quality assured database for all safety relevant elements, temperature and pressure ranges, with its focus on saline systems. This implied the use of the Pitzer approach to compute activity coefficients suitable for such conditions. Data access is possible via commonly available internet browsers under the address http://www.thereda.de. One part of the project - the data collection and evaluation for uranium - was a task of the Helmholtz-Zentrum Dresden-Rossendorf. The aquatic chemistry and thermodynamics of U(VI) and U(IV) is of great importance for geochemical modelling in repository-relevant systems. The OECD/NEA Thermochemical Database (NEA TDB) compilation is the major source for thermodynamic data of the aqueous and solid uranium species, even though this data selection does not utilize the Pitzer model for the ionic strength effect correction. As a result of the very stringent quality demands, the NEA TDB is rather restrictive and therefore incomplete for extensive modelling calculations of real systems. Therefore, the THEREDA compilation includes additional thermodynamic data of solid secondary phases formed in the waste material, the backfill and the host rock, though falling into quality assessment (QA) categories of lower accuracy. The data review process prefers log K values from solubility experiments (if available) to those calculated from thermochemical data.

Data compilation and evaluation of U(IV) and U(VI) for thermodynamic reference database THEREDA

International Nuclear Information System (INIS)

Richter, Anke; Bok, Frank; Brendler, Vinzenz

2015-01-01

THEREDA (Thermodynamic Reference Database) is a collaborative project, which has been addressed this challenge. The partners are Helmholtz-Zentrum Dresden-Rossendorf, Karlsruhe Institute of Technology (KIT-INE), Gesellschaft fuer Anlagen- und Reaktorsicherheit Braunschweig mbH (GRS), TU Bergakademie Freiberg (TUBAF) and AF-Consult Switzerland AG (Baden, Switzerland). The aim of the project is the establishment of a consistent and quality assured database for all safety relevant elements, temperature and pressure ranges, with its focus on saline systems. This implied the use of the Pitzer approach to compute activity coefficients suitable for such conditions. Data access is possible via commonly available internet browsers under the address http://www.thereda.de. One part of the project - the data collection and evaluation for uranium - was a task of the Helmholtz-Zentrum Dresden-Rossendorf. The aquatic chemistry and thermodynamics of U(VI) and U(IV) is of great importance for geochemical modelling in repository-relevant systems. The OECD/NEA Thermochemical Database (NEA TDB) compilation is the major source for thermodynamic data of the aqueous and solid uranium species, even though this data selection does not utilize the Pitzer model for the ionic strength effect correction. As a result of the very stringent quality demands, the NEA TDB is rather restrictive and therefore incomplete for extensive modelling calculations of real systems. Therefore, the THEREDA compilation includes additional thermodynamic data of solid secondary phases formed in the waste material, the backfill and the host rock, though falling into quality assessment (QA) categories of lower accuracy. The data review process prefers log K values from solubility experiments (if available) to those calculated from thermochemical data.

Parameters of a simple whole body counter and thyroid monitor established at the Dresden Felsenkeller underground laboratory

Energy Technology Data Exchange (ETDEWEB)

Sahre, P [Rossendorf Nuclear Engineering and Analytics, Inc., Dresden (Germany); Schoenmuth, T [Rossendorf Nuclear Engineering and Analytics, Inc., Dresden (Germany)

1997-03-01

At the Rossendorf Nuclear Engineering and Analytics Inc. a simple whole body counter and an iodine-thyroid monitor are used for measuring the internal contamination of workers. There is no shielding chamber in both cases. By using the chamber at the Dresden Felsenkeller underground laboratory the lower limit of detection could be improved by a factor of about 3 for whole body counting and by a factor of 2,5 for thyroid monitoring (I 131, I 125). Concerning the lower limit of detection the applicability of the German standard DIN 25 482 implemented in the Gamma-Vision software packadge is discussed in the paper. (orig.)

Cs2Te normal conducting photocathodes in the superconducting rf gun

CERN Document Server

Xiang, R; Buettig, H; Janssen, D; Justus, M; Lehnert, U; Michel, P; Murcek, P; Schamlott, A; Schneider, Ch; Schurig, R; Staufenbiel, F; Teichert, J

2010-01-01

The superconducting radio frequency photoinjector (SRF gun) is one of the latest applications of superconducting rf technology in the accelerator field. Since superconducting photocathodes with high quantum efficiency are yet unavailable, normal conducting cathode material is the main choice for SRF photoinjectors. However, the compatibility between the photocathode and the cavity is one of the challenges for this concept. Recently, a SRF gun with Cs2Te cathode has been successfully operated in Forschungszentrum Dresden-Rossendorf. In this paper, we will present the physical properties of Cs2Te photocathodes in the SC cavity, such as the quantum efficiency, the lifetime, the rejuvenation, the charge saturation, and the dark current.

New version of the reactor dynamics code DYN3D for Sodium cooled Fast Reactor analyses

Energy Technology Data Exchange (ETDEWEB)

Nikitin, Evgeny [Ecole Polytechnique Federale de Lausanne (Switzerland); Helmholtz-Zentrum Dresden-Rossendorf (HZDR) e.V., Dresden (Germany); Fridman, Emil; Bilodid, Yuri; Kliem, Soeren [Helmholtz-Zentrum Dresden-Rossendorf (HZDR) e.V., Dresden (Germany)

2017-07-15

The reactor dynamics code DYN3D being developed at the Helmholtz-Zentrum Dresden-Rossendorf is currently under extension for Sodium cooled Fast Reactor analyses. This paper provides an overview on the new version of DYN3D to be used for SFR core calculations. The current article shortly describes the newly implemented thermal mechanical models, which can account for thermal expansion effects of the reactor core. Furthermore, the methodology used in Sodium cooled Fast Reactor analyses to generate homogenized few-group cross sections is summarized. The conducted and planned verification and validation studies are briefly presented. Related publications containing more detailed descriptions are outlined for the completeness of this overview.

Forschungszentrum Rossendorf, Institute of Ion Beam Physics and Materials Research. Annual report 2004

International Nuclear Information System (INIS)

Borany, J. von; Heera, V.; Helm, M.; Jaeger, H.U.; Moeller, W.

2005-01-01

The following topics are dealt with: Silicon based electrically driven microcavity LED, ultraviolet electroluminescence from a Gd-implanted Si-metal-oxide-semiconductor device, semiconductor quantum-cascade lasers, ion beam synthesis and morphology of semiconductor memories, ion implantation, films, sputtering, ion-beam induced destabilization of nanoparticles. (HSI)

Forschungszentrum Rossendorf, Institute of Ion Beam Physics and Materials Research. Annual report 2004

Energy Technology Data Exchange (ETDEWEB)

Borany, J. von; Heera, V.; Helm, M.; Jaeger, H.U.; Moeller, W. (eds.)

2005-07-01

The following topics are dealt with: Silicon based electrically driven microcavity LED, ultraviolet electroluminescence from a Gd-implanted Si-metal-oxide-semiconductor device, semiconductor quantum-cascade lasers, ion beam synthesis and morphology of semiconductor memories, ion implantation, films, sputtering, ion-beam induced destabilization of nanoparticles. (HSI)

25 years Rossendorf research reactor RFR - retrospect, state of the art and plans

International Nuclear Information System (INIS)

Hieronymus, W.

1982-01-01

Starting from a review of the essential stages of the RFR history, future tasks are presented primarily from the point of view of operating the reactor past the year 1987. It is reported on the achieved level of utilization and on the organization of plant management. (author)

Technology challenges for SRF guns as ERL sources in view of Rossendorf work

International Nuclear Information System (INIS)

Janssen, Dietmar; Buettig, Hartmut; Evtushenko, Pavel; Lehnert, Ulf; Michel, Peter; Moeller, Karsten; Murcek, Petr; Schneider, Christof; Schurig, Rico; Staufenbiel, Friedrich; Teichert, Jochen; Xiang, Rong; Stephan, Juergen; Lehmann, Wolf-Dietrich; Kamps, Thorsten; Lipka, Dirk; Volkov, Vladimir; Will, Ingo

2006-01-01

After successful tests of a SRF gun with a superconducting half-cell cavity a new SRF photoinjector for cw operation at the ELBE linac is under development. The paper discuss the design of the injector, the technological challenges of different components, the status of manufacturing and the expected parameters

The inhomogeneous MUSIG model for the simulation of polydispersed flows

International Nuclear Information System (INIS)

Krepper, Eckhard; Lucas, Dirk; Frank, Thomas; Prasser, Horst-Michael; Zwart, Phil J.

2008-01-01

A generalized inhomogeneous multiple size group (MUSIG) model based on the Eulerian modeling framework was developed in close cooperation of ANSYS-CFX and Forschungszentrum Dresden-Rossendorf and implemented into the CFD code CFX. The model enables the subdivision of the dispersed phase into a number of size groups regarding the mass balance as well as regarding the momentum balance. In this work, the special case of polydispersed bubbly flow is considered. By simulating such flows, the mass exchanged between bubble size classes by bubble coalescence and bubble fragmentation, as well as the momentum transfer between the bubbles and the surrounding liquid due to bubble size dependent interfacial forces have to be considered. Particularly the lift force has been proven to play an important role in establishing a certain bubble size distribution dependent flow regime. In a previous study [Krepper, E., Lucas, D., Prasser, H.-M., 2005. On the modeling of bubbly flow in vertical pipes. Nucl. Eng. Des. 235, 597-611] the application of such effects were considered and justified and a general outline of such a model concept was given. In this paper the model and its validation for several vertical pipe flow situations is presented. The experimental data were obtained from the TOPFLOW test facility at the Forschungszentrum Dresden-Rossendorf (FZD). The wire-mesh technology measuring local gas volume fractions, bubble size distributions and velocities of gas and liquid phases were employed. The inhomogeneous MUSIG model approach was shown as capable of describing bubbly flows with higher gas content. Particularly the separation phenomenon of small and large bubbles is well described. This separation has been proven as a key phenomenon in the establishment of the corresponding flow regime. Weaknesses in this approach can be attributed to the characterization of bubble coalescence and bubble fragmentation, which must be further investigated

Department of Material Studies - Overview

International Nuclear Information System (INIS)

Werner, Z.

2009-01-01

Full text: The technology of modifying surfaces of technological materials by means of continuous and pulsed energy and particle beams has been intensely studied for more than 20 years. In some fields, it is currently utilized on a wide scale in industry. Continuous or pulsed ion and plasma beams play a significant role among various approaches used in this area. The research carried by Department P-IX is centered on applications of our two ion implantation facilities (ion implanters) of different kinds and unique sources of high-intensity intense plasma pulses, operated by the Department of Plasma Physics. The Department cooperates closely with Forschungszentrum Rossendorf (FZR, Dresden, Germany) in the field of analytical ion beam techniques and the use of unique ion implantation facilities. The main objectives of the Department are: · the search for new ways of modifying the surface properties of solid materials by means of continuous or pulsed ion and plasma beams and · the implementation of ion implantation techniques in national industries as a method of improving the lifetime of machine parts and tools utilized in industry. In 2008, research was focused on: · ion implantation/plasma treatment of ceramics aimed at improving their wettability in ceramic-metal joints, · ion beam synthesis and plasma pulse activation of superconducting MgB 2 phases, · cobalt and zirconium inclusions in conducting layers produced in oxide insulators (Al 2 O 3 ) by ion implantation and thermal annealing. Research was conducted in cooperation with Department P-V of IPJ, Institute of Nuclear Chemistry and Technology (Warsaw), Warsaw University of Technology, Institute of Technology of Materials for Electronics (Warsaw), Institute of Molecular Physics, Polish Academy of Sciences (Poznan), Institute of Chemical Physics PAS and Forschungszentrum Rossendorf FZR (Dresden, Germany), as well as with some industrial companies. (author)

Positron annihilation spectroscopy using high-energy photons

International Nuclear Information System (INIS)

Butterling, Maik; Jungmann, Marco; Krause-Rehberg, Reinhard; Krille, Arnold; Anwand, Wolfgang; Brauer, Gerhard; Cowan, Thomas E.; Hartmann, Andreas; Kosev, Krasimir; Schwengner, Ronald; Wagner, Andreas

2010-01-01

The superconducting electron accelerator ELBE (Electron Linac with high Brilliance and low Emittance) at the Research Centre Dresden-Rossendorf (Germany) serves as a high-intensity bremsstrahlung photon-source delivering a pulsed beam (26 MHz) with very short bunches (<5 ps). The photons are being converted into positrons by means of pair production inside the target material thus forming an intense positron source. The accelerator machine pulse is used as time reference allowing positron lifetime spectroscopy. We performed positron annihilation spectroscopy by pair production in different sample materials and used coincidence techniques to reduce the background due to scattered photons significantly in order resulting in spectra of extraordinary high quality. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

On the major DYN3D developments for fast reactor design and transient analysis

International Nuclear Information System (INIS)

Merk, B.; Kliem, S.

2013-01-01

Due to the French project ASTRID, the European CP-ESFR project, and the MYRRHA/FASTEF project, the research work on fast reactors has got a new push in Europe. Additionally to this European projects a strong project is growing in Russia based on the lead cooled fast reactor design BREST. Following this trend, the Institute of Resource Ecology at the Helmholtz-Zentrum Dresden-Rossendorf has decided to start several projects dedicated to fast reactor technology, among them the extension of the well validated LWR core simulator DYN3D. The new developments, first validation results, and the next strategic steps for the adaption of the code for the improved simulation of fast reactor cores are presented. (orig.)

On the major DYN3D developments for fast reactor design and transient analysis

Energy Technology Data Exchange (ETDEWEB)

Merk, B.; Kliem, S. [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Reactor Safety Div.

2013-07-01

Due to the French project ASTRID, the European CP-ESFR project, and the MYRRHA/FASTEF project, the research work on fast reactors has got a new push in Europe. Additionally to this European projects a strong project is growing in Russia based on the lead cooled fast reactor design BREST. Following this trend, the Institute of Resource Ecology at the Helmholtz-Zentrum Dresden-Rossendorf has decided to start several projects dedicated to fast reactor technology, among them the extension of the well validated LWR core simulator DYN3D. The new developments, first validation results, and the next strategic steps for the adaption of the code for the improved simulation of fast reactor cores are presented. (orig.)

Cs_{2}Te normal conducting photocathodes in the superconducting rf gun

Directory of Open Access Journals (Sweden)

R. Xiang

2010-04-01

Full Text Available The superconducting radio frequency photoinjector (SRF gun is one of the latest applications of superconducting rf technology in the accelerator field. Since superconducting photocathodes with high quantum efficiency are yet unavailable, normal conducting cathode material is the main choice for SRF photoinjectors. However, the compatibility between the photocathode and the cavity is one of the challenges for this concept. Recently, a SRF gun with Cs_{2}Te cathode has been successfully operated in Forschungszentrum Dresden-Rossendorf. In this paper, we will present the physical properties of Cs_{2}Te photocathodes in the SC cavity, such as the quantum efficiency, the lifetime, the rejuvenation, the charge saturation, and the dark current.

Reconditioning of the Cologne tandem after a fire at the ion source

International Nuclear Information System (INIS)

Dewald, A.; Steinert, L.

1988-01-01

In summer 1984 a fire broke out at the duoplasmatron ion source on the Cologne tandem accelerator. HCl from burnt PVC caused enormous damage by corrosion. After reconditioning the accelerator and following some improvements it was possible to operate the tandem more reliably at 9.5 MV than previously at 8 MV. Work is in progress to rebuild the injector in order to replace the inhomogeneous voltage divider at the entrance of the first tube by a homogeneous one. In addition a 90 0 injector with injection energy increased from 80 keV to 180 keV is planned. Since 1986 the Rossendorf sputter source MISS-483 has been in standard operation. (orig.)

Modelling of Cold Water Hammer with WAHA code

International Nuclear Information System (INIS)

Gale, J.; Tiselj, I.

2003-01-01

The Cold Water Hammer experiment described in the present paper is a simple facility where overpressure accelerates a column of liquid water into the steam bubble at the closed vertical end of the pipe. Severe water hammer with high pressure peak occurs when the vapor bubble condenses and the liquid column hits the closed end of the pipe. Experimental data of Forschungszentrum Rossendorf are being used to test the newly developed computer code WAHA and the computer code RELAP5. Results show that a small amount of noncondensable air in the steam bubble significantly affects the magnitude of the calculated pressure peak, while the wall friction and condensation rate only slightly affect the simulated phenomena. (author)

A study of positron properties in quartz crystals and synthetic silica glass

International Nuclear Information System (INIS)

Anwand, W.; Brauer, G.; Hesegawa, M.; Dersch, O.; Rauch, F.

2001-01-01

The monoenergetic positron beamline 'SPONSOR' at Rossendorf has been used to investigate the positron behaviour in a naturally grown Brasilian quartz, two synthetic quartz crystals of different origin, and synthetic silica glass. The measurements allow us to obtain the positron diffusion length of free positrons and Bloch para-positronium, if formed, in these materials. In addition, hydrothermal treatment of a synthetic quartz has been used to introduce hydrogen into the crystal up to a certain depth. The presence of hydrogen is found to influence the formation of para-positronium. The depth distribution of hydrogen has been measured independently by the nuclear reaction analysis, and will be discussed in comparison with the results deduced from the positron studies. (author)

Progress of the intense positron beam project EPOS

International Nuclear Information System (INIS)

Krause-Rehberg, R.; Brauer, G.; Jungmann, M.; Krille, A.; Rogov, A.; Noack, K.

2008-01-01

EPOS (the ELBE POsitron Source) is a running project to build an intense, bunched positron beam for materials research. It makes use of the bunched electron beam of the ELBE radiation source (Electron Linac with high Brilliance and low Emittance) at the Research Centre Dresden-Rossendorf (40 MeV, 1 mA). ELBE has unique timing properties, the bunch length is <5 ps and the repetition time is 77 ns. In contrast to other Linacs made for Free Electron Lasers (e.g., TTF at DESY, Hamburg), ELBE can be operated in full cw-mode, i.e., with an uninterrupted sequence of bunches. The article continues an earlier publication. It concentrates on details of the timing system and describes issues of radiation protection

The Radiation Source ELBE and its Research Program in Nuclear Physics

International Nuclear Information System (INIS)

Lehnert, U.; Michel, P.; Schwengner, R.

2005-01-01

The new radiation source 'Strahlungsquelle ELBE' at the Forschungszentrum Rossendorf (FZR) near Dresden, Germany, is a user facility that utilizes a superconducting linear accelerator to produce various secondary beams for experiments in nuclear science, solid state physics, materials research, environmental chemistry and in the life sciences. The high brilliance electron beam of up to 40 MeV and 1 mA (cw) is mainly used to drive free electron lasers producing infrared light in the 5-150 μm wavelength region. Additionally, polarized MeV-Bremsstrahlung and X-rays from electron channeling are available, facilities for neutron and positron production are under construction. The talk outlines the ongoing research activities at ELBE with special attention to the nuclear resonance fluorescence experiments

Department of Material Studies - Overview

International Nuclear Information System (INIS)

Werner, Z.

2007-01-01

The technology of modifying surfaces of practical-use materials by means of continuous and pulsed energy and particle beams has been intensely studied for more than 20 years. In some fields it is presently utilized on a wide scale in industry. Continuous or pulsed ion and plasma beams play a significant role among various approaches used in this area. The research carried by Department P-IX is centered around the use of two own ion implantation machines (ion implanters) of different kind and several world-wide unique sources of high-intensity intense plasma pulses, utilized jointly with Department P-V. The Department cooperates closely with Forschungszentrum Rossendorf (FZR, Dresden, Germany) in the field of ion-beam-based analytical techniques and the use of unique ion implantation facilities. The main objectives of the Department are: search for new ways of modifying surface properties of solid materials by means of continuous or pulsed ion and plasma beams and implementation of ion implantation technique in national industries as a method of improving the lifetime of machine parts and tools utilized in industry. In 2006 these objectives were accomplished in many ways, particularly by research on: formation of superconducting MgB 2 phases, electrical conductivity in metallic nano-layers produced in oxide insulators (Al 2 O 3 ) by ion implantation, ion implantation as a method of improving mechanical properties of stainless steels without degrading their corrosion resistance, ion implantation/plasma treatment of ceramics aimed at improving their wettability in ceramic-metal joints, methods of controlling wear of ceramic-polymer pairs used in bio-medical applications. The research was conducted in cooperation with Department P-V of IPJ, Institute of Nuclear Chemistry and Technology (Warsaw), Warsaw University of Technology, Institute of Technology of Materials for Electronics (Warsaw), and Institute of Molecular Physics Polish Academy of Sciences (Poznan

Department of Material Studies: Overview

International Nuclear Information System (INIS)

Werner, Z.

2003-01-01

Full text: The technology of modifying surfaces of industrial-use materials by means of continuous and pulsed energy beams has been intensely studied for more than 20 years. In some fields it is presently utilized on a broad scale in industry. Continuous or pulsed ion and plasma beams play a significant role among various approaches used. Department P-IX (jointly with Department P-V) utilizes some globally unique sources of intense plasma pulses, and jointly with Forschungszentrum Rossendorf (FZR, Dresden, Germany) conducts research on the application of continuous ion beams using FZR and IPJ facilities. The main objectives of the Department are: - a search for new ways of modifying surface properties of solid materials by means of pulsed plasma beams; - the implementation of ion implantation technique in national industries as a method of improving the lifetime of machine parts and tools utilized in industry. In 2002 these objectives were accomplished in many ways, particularly by research on phase changes in steel irradiated with intense pulsed plasma beams, Si-implanted TiN coatings on steel, implantation of high doses of nitrogen into aluminum, and corrosion properties of Ti surfaces alloyed with Pd by implantation and/or plasma pulses. The research was aimed at practical objectives like finding novel hard coatings, improving resistance to high temperature oxidation, reducing friction between NC6 steel-made parts without using a lubricating agent etc. The research was conducted in cooperation with Department P-V of IPJ, Institute of Nuclear Chemistry and Technology (Warsaw), Warsaw University of Technology, Institute of Technology of Materials for Electronics (Warsaw), Forschungszentrum Rossendorf FZR (Dresden, Germany), as well as with some industrial companies. Some research in 2002 was aimed at improving of the rod plasma injector generator used in our lab (the mechanism of electrode erosion during the plasma discharge, ablation of substrate material induced

Results of investigations in a fast reactor configuration with a strong heterogeneous cell structure

International Nuclear Information System (INIS)

Lehmann, E.; Albert, D.; Dietze, K.; Faehrmann, K.; Hansen, W.; Huettel, G.; Wand, H.; Osmera, B.

1984-11-01

Investigations of the neutron flux spectrum, of the energy dependent importance function and of sample reactivities were performed in a fast reactor configuration characterized by a marked neutronic microstructure which is produced by the insertion of pellets of polyethylene and cadmium. Contrary to results of calculations with a homogenized composition, values obtained by means of the tree programs CARMEN, YARAB and P1X, developed in Rossendorf, agree well with measurements. Furthermore it could be shown that an adjoint weighting for the determination of cell-averaged values of the importance function is justified. In a configuration with larger heterogeneity induced by the aggregation of four uranium pellets significant spectral differences between uranium and material zones, respectively, show up in activation measurements as well as in sample reactivity determinations. (author)

Chlorine measurements at the 5MV French AMS national facility ASTER: Associated external uncertainties and comparability with the 6MV DREAMS facility

Science.gov (United States)

Braucher, R.; Keddadouche, K.; Aumaître, G.; Bourlès, D. L.; Arnold, M.; Pivot, S.; Baroni, M.; Scharf, A.; Rugel, G.; Bard, E.

2018-04-01

After 6 years of 36Cl routine operation, more than 6000 unknown samples have been measured at the 5MV French accelerator mass spectrometry (AMS) national facility ASTER (CEREGE, Aix en Provence). This paper presents the long term behavior of ASTER through the analysis of the measurements of the most used chlorine standards and reference materials, KNSTD1600, SM-Cl-12 and SM-CL-13 over a 46 months' time period. Comparison of measured chlorine concentrations (both 35Cl and 36Cl) from ice samples on two AMS facilities operating at 5MV (ASTER) and 6MV (DREAMS, Helmholtz-Zentrum Dresden-Rossendorf) and normalizing to two different reference materials agree within uncertainties making both reference materials (SM-Cl-12 and KNSTD1600) suitable for 36Cl measurement at ASTER.

Annual report 2012. Institute of Resource Ecology

International Nuclear Information System (INIS)

Brendler, Vinzenz

2013-01-01

The Institute of Resource Ecology (IRE) is one of the currently eight institutes of the Helmholtz-Zentrum Dresden-Rossendorf (HZDR). The research activities are fully integrated into the program ''Nuclear Safety Research'' of the Helmholtz Association and focused on the topics ''Safety of Nuclear Waste Disposal'' and ''Safety Research for Nuclear Reactors''. With the integration of the division of ''Reactor Safety'' from the former ''Institute of Safety Research'' nuclear research at HZDR is now mainly concentrated within this institute. In addition, various activities have been started investigating chemical and environmental aspects of processing and recycling of strategic metals, namely rare earth elements. Here, a knowledge transfer from the nuclear to the non-nuclear community, branching thermodynamics and spectroscopy, has been established. This also strengthens links to the recently established ''Helmholtz-Institute Freiberg for Resource Technology''.

Annual report 2012. Institute of Resource Ecology

Energy Technology Data Exchange (ETDEWEB)

Brendler, Vinzenz [ed.

2013-09-01

The Institute of Resource Ecology (IRE) is one of the currently eight institutes of the Helmholtz-Zentrum Dresden-Rossendorf (HZDR). The research activities are fully integrated into the program ''Nuclear Safety Research'' of the Helmholtz Association and focused on the topics ''Safety of Nuclear Waste Disposal'' and ''Safety Research for Nuclear Reactors''. With the integration of the division of ''Reactor Safety'' from the former ''Institute of Safety Research'' nuclear research at HZDR is now mainly concentrated within this institute. In addition, various activities have been started investigating chemical and environmental aspects of processing and recycling of strategic metals, namely rare earth elements. Here, a knowledge transfer from the nuclear to the non-nuclear community, branching thermodynamics and spectroscopy, has been established. This also strengthens links to the recently established ''Helmholtz-Institute Freiberg for Resource Technology''.

VESPA. Behaviour of long-lived fission and activation products in the nearfield of a nuclear waste repository and the possibilities of their retention

Energy Technology Data Exchange (ETDEWEB)

Bischofer, Barbara; Hagemann, Sven [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) gGmbH, Koeln (Germany); Altmaier, Marcus [Karlsruher Institut fuer Technologie (KIT) (Germany); and others

2016-06-15

The present document is the final report of the Joint Research Project VESPA (Behaviour of Long-lived Fission and Activation Products in the Near Field of a Nuclear Waste Repository and the Possibilities of Their Retention), started in July 2010 with a duration of four years. The following four institutions were collaborative Partners in VESPA: - Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) gGmbH - Institut fuer Energie- und Klimaforschung, IEK-6: Nukleare Entsorgung und Reaktorsicherheit, Forschungszentrum Juelich (FZJ) - Institut fuer Ressourcenoekologie (IRE), Helmholtz-Zentrum Dresden-Rossendorf (HZDR) - Institut fuer Nukleare Entsorgung (INE), Karlsruher Institut fuer Technologie (KIT) VESPA was funded by the German Federal Ministry of Economics and Energy (BMWi) under the contract numbers 02 E 10770 (GRS), 02 E 10780 (FZJ-IEF-6), 02 E 10790 (HZDR-IRE), 02 E 10800 (KIT-INE).

Tritium depth profiling in carbon samples from fusion experiments

International Nuclear Information System (INIS)

Friedrich, M.; Pilz, W.; Sun, G.; Behrisch, R.; Garcia-Rosales, C.; Bekris, N.; Penzhorn, R.-D.

2000-01-01

Tritium depth profiling by accelerator mass spectrometry has been performed at the Rossendorf 3 MV Tandetron. Tritium particles are counted after the accelerator using a semiconductor detector, while deuterium and other light elements are simultaneously measured with the Faraday cup between the injection magnet and the accelerator. Depth profiles have been measured in carbon samples cut from the first wall tiles of the Garching fusion experiment ASDEX-Upgrade and of the European fusion experiment JET, Culham/UK. Tritium contents in the JET samples were up to six orders higher than in samples from ASDEX-Upgrade. Tritium beam currents from samples with high tritium content were measured partly in the Faraday cup before the accelerator. A dedicated tritium AMS facility with an air-insulated 100 kV tandem accelerator is under construction

The multipurpose thermalhydraulic test facility TOPFLOW: an overview on experimental capabilities, instrumentation and results

International Nuclear Information System (INIS)

Prasser, H.M.; Beyer, M.; Carl, H.; Manera, A.; Pietruske, H.; Schuetz, P.; Weiss, F.P.

2006-01-01

A new multipurpose thermalhydraulic test facility TOPFLOW (TwO Phase FLOW) was built and put into operation at Forschungszentrum Rossendorf in 2002 and 2003. Since then, it has been mainly used for the investigation of generic and applied steady state and transient two phase flow phenomena and the development and validation of models of computational fluid dynamic (CFD) codes in the frame of the German CFD initiative. The advantage of TOPFLOW consists in the combination of a large scale of the test channels with a wide operational range both of the flow velocities as well as of the system pressures and temperatures plus finally the availability of a special instrumentation that is capable in high spatial and temporal resolving two phase flow phenomena, for example the wire-mesh sensors. (orig.)

Operation results and investigations on decommissioning of the molybdenum-99 production plant Rossendorf - AMOR-I

International Nuclear Information System (INIS)

Bernhard, G.; Friedrich, H.; Boessert, W.; Eckardt, A.

1993-01-01

Original fuel elements of a research reactor were reprocessed for fission molybdenum production in the facility AMOR-I. In a 10 years operation 8.5*10 15 Bq Mo-99 were produced in more than 400 runs. The production results and many experiences were described in this report. Further a view is given on the strategy of decommissioning. There are shown results of fission product adsorption on and desorption from material surfaces. Possibilities of decontamination are described. The simultaneous effect of corrosion and radioactive radiation on different materials is discussed. This paper is a basis of the licence procedure for decommissioning of the AMOR-I-plant. (orig./HP) [de

Investigation of coolant mixture in pressurized water reactors at the Rossendorf mixing test facility ROCOM

International Nuclear Information System (INIS)

Grunwald, G.; Hoehne, T.; Prasser, H.M.; Richter, K.; Weiss, F.P.

1999-01-01

During the so-called boron dilution or cold water transients at pressurized water reactors too weakly borated water or too cold water, respectively, might enter the reactor core. This results in the insertion of positive reactivity and possibly leads to a power excursion. If the source of unborated or subcooled water is not located in all coolant loops but in selected ones only, the amount of reactivity insertion depends on the coolant mixing in the downcomer and lower plenum of the reactor pressure vessel (RPV). Such asymmetric disturbances of the coolant temperature or boron concentration might e.g. be the result of a failure of the chemical and volume control system (CVCS) or of a main steam line break (MSLB) that does only affect selected steam generators (SG). For the analysis of boron dilution or MSLB accidents coupled neutron kinetics/thermo-hydraulic system codes have been used. To take into account coolant mixing phenomena in these codes in a realistic manner, analytical mixing models might be included. These models must be simple and fast running on the one hand, but must well describe the real mixing conditions on the other hand. (orig.)

Modern recording systems for services able to meet the competition; Moderne Erfassungssysteme fuer wettbewerbsfaehige Dienstleistungen

Energy Technology Data Exchange (ETDEWEB)

Drumm, M.

2000-07-01

Modern recording systems form the basis for competitive services. They are, however, only successful when integrated precisely into a lean running organization. By means of practical examples the necessity to place great emphasis on the costs of a system besides the investment costs when deciding about a recording system, will be examined. The significant changes on the energy market and the increasing demand of the housing economy for a comprehensive offer of services from the supply industry are main initiators for a whole new line of businesses on the supply economy sector. The great challenge for the supply industry lies in the task to install lean and effective system which are on one hand reliable and easy to handle for the whole duration of the contract and on the other hand are so cost efficient, that an adequate profitability can be ensured (see also: 'The secret winners', Zfk October 1999). A decisive factor for this reason is the metering technology, which has to ensure for the whole duration of the contract that correct consumption values are registered, on the basis of which as fast and punctual as possible a legally safe invoicing can be prepared. (orig.) [German] Moderne Erfassungssysteme bilden die Grundlage fuer wettbewerbsfaehige Dienstleistungen, die jedoch erst bei sauberer Einbindung in eine schlanke Ablauforganisation erfolgreich sind. Anhand von Praxisbeispielen wird die Notwendigkeit betrachtet, bei der Entscheidung fuer ein Erfassungssystem neben den Investitionskosten den Systemkosten entscheidendes Gewicht zu verleihen. (orig.)

Investigation of the possibility of a calculative reactor safety estimation in the licence procedure for nuclear reactors

International Nuclear Information System (INIS)

Adler, B.; Kampf, T.

1975-12-01

Up to now it is impossible to calculate completely the safety of nuclear reactors. Therefore the authors have collected and employed a number of at a high degree independent safety parameters for mathematical evaluation of the reactor safety. By means of computer programs such parameters from about 400 research reactors have been analysed and the fluctuation ranges of their greatest density were determined. The limits of these fluctuation ranges are quickly available and can be used as recommended values for the layout and for the safety estimation of research reactors. A comparison of the existing layout recommendations and the determined fluctuation ranges in most cases shows a good agreement. In some cases corrections and new layout recommendations have been proposed. The determined fluctuation ranges found their first practical application in the estimation of the Rossendorf Equipment for Critical Experiments (RAKE). (author)

Status and future prospects of SRF gun developments

International Nuclear Information System (INIS)

Teichert, Jochen

2006-01-01

While the concepts of DC and normal-conducting photo-injectors are well proofed, the SRF gun development still possesses a high risk. Challenges are the thermal and contaminant isolation needed between the cathode and superconducting cavity, the choice of the right photocathode and its life time, the difficulty of coupling high-average power into the gun, and beam excitation of higher order cavity modes. But in combination with SRF linacs, the SRF guns are the best solution for high current and CW operation. Thus, several R and D projects of SRF gun have been launched. The talk will give an overview of the history and progress of the SRF gun development. In more detail the technical concept, performance, and status of the Rossendorf superconducting RF gun project, a collaboration of BESSY, DESY, MBI and FZR, will be presented. (author)

Energy-dispersive study of the interaction of fast neutrons with matter. Common final report of the DFG projects GR 1674/2 and FR 575/5 together with the institute for nuclear and particle physics, technical university Dresden; Energiedispersive Untersuchung der Wechselwirkung schneller Neutronen mit Materie. Gemeinsamer Abschlussbericht der DFG Projekte GR 1674/2 und FR 575/5, zusammen mit dem Institut fuer Kern- und Teilchenphysik, Technische Universitaet Dresden

Energy Technology Data Exchange (ETDEWEB)

Altstadt, E.; Beckert, C. [Forschungszentrum Rossendorf e.V. (FZR) (Germany). Inst. fuer Sicherheitsforschung; Beyer, R. [Forschungszentrum Rossendorf e.V. (FZR), Dresden (DE). Inst. fuer Kern- und Hadronenphysik] [and others

2005-04-01

In this final report on the research project ''Energy-dispersive study of the interaction of fast neutrons with matter, especially materials for fusion and materials from fission reactors the status reached after three years promotion is described. The aim of this project is the construction and first usage of a very complex time-of-flight system for the study of the interaction of fast neutrons with construction materials for fusion and fission reactors as well as with long-lived radioisotopes. Furthermore astrophysically relevant experiments on problems of the element synthesis shall be performed. The whole project is devided into two sections: 1. Development, construction and test of a pulsed photoneutron source at the ELBE accelerator of the FZ Rossendorf, 2. Application of the photoneutron sources for measurements of cross sections induced by fast, energy-selected neutrons.

Results of substitution of the Nal by a Ge detector in a simple shadow shield whole body counter

International Nuclear Information System (INIS)

Sahre, P.; Schoenmuth, T.; Thieme, K.

1997-01-01

Since 1976 a whole body counter (WBC) has been used at the Rossendorf Research Centre for measuring the internal contamination of workers. The WBC with the Germanium detector is given schematically and visually. The WBC is a shadow shield type with a tilted chair having only one detector. Table 1 contains the parameters of the WBC. It can be seen that the WBC is a simple counter. Therefore, taking into account the experiences of McCurdy, a lot of improvements were expected form the simple substitution of a HP Germanium detector for a NaI (TI) detector, i.e. despite a decrease in the sensitive detection volume, an enhancement of all quantifiable results (e.g. lower limit of detection and time for analysis of the spectrum) and above all the reliability and automation of nuclide identification were expected. (orig./SR)

Tritium depth profiling in carbon by accelerator mass spectrometry

International Nuclear Information System (INIS)

Friedrich, M.; Pilz, W.; Sun, G.; Behrisch, R.; Garcia-Rosales, C.; Bekris, N.; Penzhorn, R.-D.

2000-01-01

Tritium depth profiling measurements by accelerator mass spectrometry have been performed at the facility installed at the Rossendorf 3 MV Tandetron. In order to achieve a uniform erosion at the target surface inside a commercial Cs ion sputtering source and to avoid edge effects, the samples were mechanically scanned and the signals were recorded only during sputtering at the centre of the sputtered area. The sputtered negative ions were mass analysed by the injection magnet of the Tandetron. Hydrogen and deuterium profiles were measured with the Faraday cup between the injection magnet and the accelerator, while the tritium was counted after the accelerator with semiconductor detectors. Depth profiles have been measured for carbon samples which had been exposed to the plasma at the first wall of the Garching fusion experiment ASDEX-Upgrade and from the European fusion experiment JET, Culham, UK

Results of substitution of the Nal by a Ge detector in a simple shadow shield whole body counter

Energy Technology Data Exchange (ETDEWEB)

Sahre, P.; Schoenmuth, T. [Nuclear Engineering and Analytics Inc. Rossendorf, Dresden (Germany); Thieme, K. [Amersham Buchler Ltd. und Co., Braunschweig (Germany)

1997-12-01

Since 1976 a whole body counter (WBC) has been used at the Rossendorf Research Centre for measuring the internal contamination of workers. The WBC with the Germanium detector is given schematically and visually. The WBC is a shadow shield type with a tilted chair having only one detector. Table 1 contains the parameters of the WBC. It can be seen that the WBC is a simple counter. Therefore, taking into account the experiences of McCurdy, a lot of improvements were expected form the simple substitution of a HP Germanium detector for a NaI (TI) detector, i.e. despite a decrease in the sensitive detection volume, an enhancement of all quantifiable results (e.g. lower limit of detection and time for analysis of the spectrum) and above all the reliability and automation of nuclide identification were expected. (orig./SR)

4. Workshop - Measurement techniques of stationary and transient multiphase flow

International Nuclear Information System (INIS)

Prasser, H.M.

2001-05-01

In November 2000, the 4th Workshop on Measurement Techniques for Stationary and Transient Multiphase Flows took place in Rossendorf. Three previous workshops of this series were national meetings; this time participants from different countries took part. The programme comprised 14 oral presentations, 9 of which are included in these proceedings in full length. A special highlight of the meeting was the main lecture ''Ultrasonic doppler method for bubbly flow measurement'' of Professor Masanori Aritomi, Dr. Hiroshige Kikura and Dr. Yumiko Suzuki. The workshop again dealt with high-resolution phase distribution and phase velocity measurement techniques based on electrical conductivity, ultrasound, laser light and high-speed cinematography. A number of presentations were dedicated to the application of wire-mesh sensors developed by FZR for different applications used by the Technical Universities of Delft and Munich and the Tokyo Institute of Technology. (orig.)

Nuclear engineering in the linelight

International Nuclear Information System (INIS)

Blumentritt, G.; Schwaar, L.

1979-01-01

An insight is given into the state of art of nuclear engineering considering only essential problems. The subject is covered under the following headings: (1) the way to nuclear fission, (2) detectors for nuclear radiation, (3) measuring systems for nuclear radiation, (4) radioisotopes in industry, (5) aids in medicine, (6) radiation absorption and its utilization, (7) use of radioisotopes in research, (8) the chain reaction in a nuclear reactor, (9) power from nuclear power plants, (10) pressurized water reactors (PWR), (11) high-temperature reactors (HTGR), (12) fast breeder reactors (FBR), (13) nuclear energetics - a new branch of industry, (14) nuclear explosions, (15) nuclear research at Rossendorf, and (16) the energy of the future. An appendix includes definitions of terms used in nuclear engineering. The book is written for a wide circle of readers who are interested in the peaceful uses of nuclear energy

Development of destructive methods of burn-up determination and their application on WWER type nuclear fuels

International Nuclear Information System (INIS)

Hermann, A.; Stephan, H.; Nebel, D.

1984-03-01

Results are described of a cooperation between the Central Institute of Nuclear Research Rossendorf and the Radium Institute 'V.G. Chlopin' Leningrad in the field of destructive burn-up determination. Laboratory methods of burn-up determination using the classical monitors 137 Cs, 106 Ru, 148 Nd and isotopes of heavy metals (U, Pu) as well as the usefulness of 90 Sr, stable isotopes of Ru and Mo as monitors are dealt with. The analysis of the fuel components uranium (spectrophotometry, potentiometric titration, mass-spectrometric isotope dilution) and plutonium (spectrophotometry, coulometric titration, mass- and alpha-spectrometric isotope dilution) is fully described. Possibilities of increasing the reproducibility (automatic adjusting of measurement conditions) and the sensibility (ion impuls counting) of mass-spectrometric measurements are proposed and applied to a precise determination of Am and Cm isotopic composition. The methods have been used for burn-up analysis of spent WWER (especially WWER-440) fuel. (author)

Small Sample Reactivity Measurements in the RRR/SEG Facility: Reanalysis using TRIPOLI-4

Energy Technology Data Exchange (ETDEWEB)

Hummel, Andrew [Idaho National Lab. (INL), Idaho Falls, ID (United States); Palmiotti, Guiseppe [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2016-08-01

This work involved reanalyzing the RRR/SEG integral experiments performed at the Rossendorf facility in Germany throughout the 1970s and 80s. These small sample reactivity worth measurements were carried out using the pile oscillator technique for many different fission products, structural materials, and standards. The coupled fast-thermal system was designed such that the measurements would provide insight into elemental data, specifically the competing effects between neutron capture and scatter. Comparing the measured to calculated reactivity values can then provide adjustment criteria to ultimately improve nuclear data for fast reactor designs. Due to the extremely small reactivity effects measured (typically less than 1 pcm) and the specific heterogeneity of the core, the tool chosen for this analysis was TRIPOLI-4. This code allows for high fidelity 3-dimensional geometric modeling, and the most recent, unreleased version, is capable of exact perturbation theory.

2010 annual meeting on nuclear technology. Workshop on ''Preservation of competence in nuclear technology''

International Nuclear Information System (INIS)

Steinwarz, Wolfgang

2010-01-01

Within the two-day workshop on ''Preservation of Competence in Nuclear Technology'', 21 young scientists competed for the ''Competence Prize'' awarded by Siempelkamp Nukleartechnik for the twelfth time. They reported about their term papers, diploma or doctoral theses focusing on reactor technology and reactor safety, the development of innovative reactor systems, and waste management. For the first time, contributions this year were presented also from the field of radiation protection. The jury composed of Prof. T. Schulenberg (Karlsruhe Institute of Technology), Prof. M.K. Koch (Ruhr University, Bochum), and Dr. W. Steinwarz (Siempelkamp Nukleartechnik) assessed the advance compacts as well as the oral presentations. The winner of the 2010 Competence Prize is Heiko Herbell of the Karlsruhe Institute of Technology. Cornelia Heintze of the Dresden-Rossendorf Research Center, and Carola Hartel of the GSI Helmholtz Center for Heavy Ion Research won the second and third prizes. (orig.)

4. Workshop - Measurement techniques of stationary and transient multiphase flow

Energy Technology Data Exchange (ETDEWEB)

Prasser, H.M. (ed.)

2001-05-01

In November 2000, the 4th Workshop on Measurement Techniques for Stationary and Transient Multiphase Flows took place in Rossendorf. Three previous workshops of this series were national meetings; this time participants from different countries took part. The programme comprised 14 oral presentations, 9 of which are included in these proceedings in full length. A special highlight of the meeting was the main lecture ''Ultrasonic doppler method for bubbly flow measurement'' of Professor Masanori Aritomi, Dr. Hiroshige Kikura and Dr. Yumiko Suzuki. The workshop again dealt with high-resolution phase distribution and phase velocity measurement techniques based on electrical conductivity, ultrasound, laser light and high-speed cinematography. A number of presentations were dedicated to the application of wire-mesh sensors developed by FZR for different applications used by the Technical Universities of Delft and Munich and the Tokyo Institute of Technology. (orig.)

Simulation of an MSLB scenario using the 3D neutron kinetic core model DYN3D coupled with the CFD software Trio-U

Energy Technology Data Exchange (ETDEWEB)

Grahn, Alexander, E-mail: a.grahn@hzdr.de; Gommlich, André; Kliem, Sören; Bilodid, Yurii; Kozmenkov, Yaroslav

2017-04-15

Highlights: • Improved thermal-hydraulic description of nuclear reactor cores. • Providing reactor dynamics code with realistic thermal-hydraulic boundary conditions. • Possibility of three-dimensional flow phenomena in the core, such as cross flow, flow reversal. • Simulation at higher spatial resolution as compared to system codes. - Abstract: In the framework of the European project NURESAFE, the reactor dynamics code DYN3D, developed at Helmholtz-Zentrum Dresden-Rossendorf (HZDR), was coupled with the Computational Fluid Dynamics (CFD) solver Trio-U, developed at CEA France, in order to replace DYN3D’s one-dimensional hydraulic part with a full three-dimensional description of the coolant flow in the reactor core at higher spatial resolution. The present document gives an introduction into the coupling method and shows results of its application to the simulation of a Main Steamline Break (MSLB) accident of a Pressurised Water Reactor (PWR).

Transmutation of high-level radioactive waste - Perspectives

CERN Document Server

Junghans, Arnd; Grosse, Eckart; Hannaske, Roland; Kögler, Toni; Massarczyk, Ralf; Schwengner, Ronald; Wagner, Andreas

2014-01-01

In a fast neutron spectrum essentially all long-lived actinides (e.g. Plutonium) undergo fission and thus can be transmuted into generally short lived fission products. Innovative nuclear reactor concepts e.g. accelerator driven systems (ADS) are currently in development that foresee a closed fuel cycle. The majority of the fissile nuclides (uranium, plutonium) shall be used for power generation and only fission products will be put into final disposal that needs to last for a historical time scale of only 1000 years. For the transmutation of high-level radioactive waste a lot of research and development is still required. One aspect is the precise knowledge of nuclear data for reactions with fast neutrons. Nuclear reactions relevant for transmutation are being investigated in the framework of the european project ERINDA. First results from the new neutron time-of-flight facility nELBE at Helmholtz-Zentrum Dresden-Rossendorf will be presented.

Fabrication, Tuning, Treatment and Testing of Two 3.5 Cell Photo-Injektor Cavities for the ELBE Linac

CERN Document Server

Arnold, A; Teichert, J; Xiang, R; Eremeev, G V; Kneisel, P; Stirbet, M; Turlington, L

2011-01-01

As part of a CRADA (Cooperative Research and Development Agreement) between Helmholtz-Zentrum Dresden-Rossendorf (HZDR) and Thomas Jefferson Lab National Accelerator Facility (TJNAF) we have fabricated and tested two 1.3 GHz 3.5 cell photo-injector cavities from polycrystalline RRR niobium and large grain RRR niobium, respectively. The cavity with the better performance will replace the presently used injector cavity in the ELBE linac [1]. The cavities have been fabricated and pre-tuned at TJNAF, while the more sophisticated final field tuning; the adjustment of the external couplings and the field profile measurement of transverse electric modes for RF focusing [2] was done at HZDR. The following standard surface treatment and the vertical test were carried out at TJNAF’s production facilities. A major challenge turned out to be the rinsing of the cathode cell, which has small opening (Ø10 mm) to receive the cathode stalk. Another unexpected problem encountered after etching, since large visible defects a...

Nuclear Deformation and Neutron Excess as Competing Effects for Dipole Strength in the Pygmy Region

Science.gov (United States)

Massarczyk, R.; Schwengner, R.; Dönau, F.; Frauendorf, S.; Anders, M.; Bemmerer, D.; Beyer, R.; Bhatia, C.; Birgersson, E.; Butterling, M.; Elekes, Z.; Ferrari, A.; Gooden, M. E.; Hannaske, R.; Junghans, A. R.; Kempe, M.; Kelley, J. H.; Kögler, T.; Matic, A.; Menzel, M. L.; Müller, S.; Reinhardt, T. P.; Röder, M.; Rusev, G.; Schilling, K. D.; Schmidt, K.; Schramm, G.; Tonchev, A. P.; Tornow, W.; Wagner, A.

2014-02-01

The electromagnetic dipole strength below the neutron-separation energy has been studied for the xenon isotopes with mass numbers A =124, 128, 132, and 134 in nuclear resonance fluorescence experiments using the γELBE bremsstrahlung facility at Helmholtz-Zentrum Dresden-Rossendorf and the HIγS facility at Triangle Universities Nuclear Laboratory Durham. The systematic study gained new information about the influence of the neutron excess as well as of nuclear deformation on the strength in the region of the pygmy dipole resonance. The results are compared with those obtained for the chain of molybdenum isotopes and with predictions of a random-phase approximation in a deformed basis. It turned out that the effect of nuclear deformation plays a minor role compared with the one caused by neutron excess. A global parametrization of the strength in terms of neutron and proton numbers allowed us to derive a formula capable of predicting the summed E1 strengths in the pygmy region for a wide mass range of nuclides.

Gamma-induced Positron Spectroscopy (GiPS) at a superconducting electron linear accelerator

International Nuclear Information System (INIS)

Butterling, Maik; Anwand, Wolfgang; Cowan, Thomas E.; Hartmann, Andreas; Jungmann, Marco; Krause-Rehberg, Reinhard; Krille, Arnold; Wagner, Andreas

2011-01-01

A new and unique setup for Positron Annihilation Spectroscopy has been established and optimized at the superconducting linear electron accelerator ELBE at Helmholtz-Zentrum Dresden-Rossendorf (Germany). The intense, pulsed (26 MHz) photon source (bremsstrahlung with energies up to 16 MeV) is used to generate positrons by means of pair production throughout the entire sample volume. Due to the very short gamma bunches (< 5 ps temporal length), the facility for Gamma-induced Positron Spectroscopy (GiPS) is suitable for positron lifetime spectroscopy using the accelerator's radiofrequency as time reference. Positron lifetime and Doppler broadening Spectroscopy are employed by a coincident measurement (Age-Momentum Correlation) of the time-of-arrival and energy of the annihilation photons which in turn significantly reduces the background of scattered photons resulting in spectra with high signal to background ratios. Simulations of the setup using the GEANT4 framework have been performed to yield optimum positron generation rates for various sample materials and improved background conditions.

Highly-resolving Rutherford-scattering spectroscopy with heavy ions

International Nuclear Information System (INIS)

Klein, C.

2003-10-01

in the present thesis for the first time the Browne-Buechner spectrometer for the highly resolving ion-beam analysis in the ion beam center Rossendorf is completely presented. A main topic of this theis lied in the apparative construction and the taking-into-operation of the spectrometer and the scattering chamber including the facilities for the sample treatment and characterization. In the framework of this thesis for the chosen measurement arrangement the experimental conditions were elaborated, which allow the routine-like application of the spectrometer for analyses of thin-film systems. for C and Li ions as incident particles especially the straggling was more precisely determined in a large range of materials. By means of the spectrometer also the interaction of the ion with the solid respectively single atoms on its surface could be studied. For the first time the mean charge-state after the single collision on a gold atom was determined for differently heavy ions in a wide energy range

The synchrotron light source ROSY

International Nuclear Information System (INIS)

Einfeld, D.; Buettig, H.; Dienel, S.; Glaeser, W.; Goetz, T.; Guratzsch, H.; Hartmann, B.; Janssen, D.; Krug, H.; Linnemann, J.; Matz, W.; Murphy, J.B.; Neumann, W.; Oehme, W.; Picard, M.; Plesko, M.; Proehl, D.; Schlenk, R.; Tomassini, D.; Tyrroff, H.

1994-01-01

ROSY, a 3rd generation synchrotron light source, has been proposed to be built at the Research Center Rossendorf/Dresden in Germany. With its low emittance and optimized space for installing insertion devices ROSY will be the first synchrotron radiation source in the 3 GeV range in Europe, dedicated to materials research and industrial application. The critical wavelength of the synchrotron radiation spectra was designed to be 0.15 nm corresponding to a critical photon energy of 8.4 keV. It is proposed to use a ''modified multiple bend achromat'' (MBA) lattice in order to get a compact machine as well as a low emittance. For 3 GeV an emittance smaller than 30π nm rad can be obtained. With a fourfold symmetry and two larger straight sections within the achromatic arcs the circumference is 148 m. 23% of the circumference can be used for installing insertion devices. (orig.)

CERN's role in medical applications

CERN Multimedia

Antonella Del Rosso

2014-01-01

Last week, CERN hosted the first meeting of the International Strategy Committee for medical applications. This Committee will help CERN establish its roadmap in the field of research and development activities for medical applications. Here the CERN Bulletin speaks with the Chair of the Committee as he shares his expectations and his vision.   Dr Michael Baumann is the Director of the Radiation Oncology department at the Carl Gustav Carus University Hospital in Dresden and of the Institute for Radiooncology of the Helmholtz-Zentrum Dresden-Rossendorf (Germany). He has recently been appointed Chair of CERN’s International Strategy Committee for medical applications – the team of experts who will advise the CERN Medical Applications Study Group led by Steve Myers. “CERN has a tremendous record in physics and basic research,” says Baumann. “I think that it has a very important role in steering some of the R&D that cannot be done at universities ...

Tritium depth profiling by AMS in carbon samples from fusion experiments

International Nuclear Information System (INIS)

Friedrich, M.; Pilz, W.; Sun, G.; Behrisch, R.; Garcia-Rosales, C.

2001-01-01

Tritium depth profiling measurements by accelerator mass spectrometry have been performed at a facility installed at the Rossendorf 3 MV Tandetron. In order to achieve an uniform erosion at the target surface inside of a commercial Cs ion sputtering source and to avoid edge effects, the samples were mechanically scanned inside of a commercial Cs sputter ion source. The sputtered negative ions were mass analysed by the injection magnet of the Tandetron. The tritium ions are counted after the acceleration with semiconductor detectors. Depth profiles have been measured for carbon samples which had been exposed to the plasma at the first wall of the Garching fusion experiment ASDEX-Upgrade and from the European fusion experiment JET, Culham/UK. A dedicated AMS facility with an air-insulated 100 kV tandem accelerator for depth profiling measurements at samples with high tritium concentration is under construction. First results of test operation are presented. (orig.)

Coupling of the neutron-kinetic core model DYN3D with the thermal hydraulic code FLICA-4 within the NURESIM platform

International Nuclear Information System (INIS)

Gommlich, A.; Kliem, S.; Rohde, U.; Gomez, A.; Sanchez, V.

2010-01-01

Within the FP7 Collaborative Project NURISP (NUclear Reactor Integrated Simulation Project) new and significant steps will be done towards a European Reference Simulation Platform for applications relevant to present PWR and BWR and to future reactors. The first step towards this target has been made during the FP6 NURESIM Integrated Project, where the already common and well-proven NURESIM informatics platform has been developed. This platform is based on the open source software SALOME. The 3D neutron kinetic core model DYN3D developed at Forschungszentrum Dresden-Rossendorf is part of the NURESIM platform. Within the NURESIM project, a SALOME based pre-processor for creation of DYN3D input data sets via GUI has been developed. DYN3D has been implemented into SALOME as black box, which allowed an independent execution. A conversion of the DYN3D result file into SALOME format was developed which opened the possibility using SALOME tools to visualize DYN3D results. (orig.)

Joint annual report 1984

International Nuclear Information System (INIS)

Hennig, K.

1985-06-01

An account is given on the activities in nuclear and solid state physcis. In the field of relativistic nuclear physcis first measurements at the Synchrophasotron of the JINR Dubna are presented. Nuclear reactions with heavy ions have been investigated at the cyclotron U-300 of the JINR. Studies of few-nucleon problems and measurements of fission cross sections at the tandem accelerator at Rossendorf have been continued. High spin states in transition nuclei (A approximately 80) and semimagic nuclei have been studied. Works in nuclear theory comprise heavy ion physics, plasma transitions in hot nuclear matter, antikaon production, hypernuclei and deformed nuclei, the time-dependent Hartree-Fock method, meson exchange, and new aspects of shell models. Various studies in solid state physics are presented, including the following: high-dose implantation in metals and semiconductors, tempering in semiconductor materials, light pulse annealing in Si, neutron diffraction in texture analysis, application of Si in the field of sensor technology

Evolution of the two-phase flow in a vertical tube-decomposition of gas fraction profiles according to bubble size classes using wire-mesh sensors

Energy Technology Data Exchange (ETDEWEB)

Prasser, H.M.; Krepper, E.; Lucas, D. [Forschungszentrum Rossendorf e.V., Dresden (Germany)

2002-01-01

The wire-mesh sensor developed by the Forschungszentrum Rossendorf produces sequences of instantaneous gas fraction distributions in a cross section with a time resolution of 1200 frames per second and a spatial resolution of about 2-3 mm. At moderate flow velocities (up to 1-2 m.s{sup -1}), bubble size distributions can be obtained, since each individual bubble is mapped in several successive distributions. The method was used to study the evolution of the bubble size distribution in a vertical two-phase flow. For this purpose, the sensor was placed downstream of an air injector, the distance between air injection and sensor was varied. The bubble identification algorithm allows to select bubbles of a given range of the effective diameter and to calculate partial gas fraction profiles for this diameter range. In this way, the different behaviour of small and large bubbles in respect to the action of the lift force was observed in a mixture of small and large bubbles. (authors)

Beam Loss Detection at Radiation Source ELBE

CERN Document Server

Michel, P; Schurig, R; Langenhagen, H

2003-01-01

The Rossendorf superconducting Electron Linac of high Brilliance and low Emittance (ELBE) delivers an 40 MeV, 1 mA cw-beam for different applications such as bremsstrahlung production, electron channelling, free-electron lasers or secondary particle beam generation. In this energy region in case of collisions of the electron beam with the pipe nearly all beam power will be deposited into the pipe material. Therefore a reliable beam loss monitoring is essential for machine protection at ELBE. Different systems basing on photo multipliers, compton diodes and long ionization chambers were studied. The pros and cons of the different systems will be discussed. Ionization chambers based on air-isolated RF cables installed some cm away parallel to the beam line turned out to be the optimal solution. The beam shut-off threshold was adjusted to 1 μC integral charge loss during a 100 ms time interval. Due to the favourable geometry the monitor sensitivity varies less than ±50% along the beam line (di...

Fast neutron measurements at the nELBE time-of-flight facility

Directory of Open Access Journals (Sweden)

Junghansa A. R.

2015-01-01

Full Text Available The compact neutron-time-of-flight facility nELBE at the superconducting electron accelerator ELBE of Helmholtz-Zentrum Dresden-Rossendorf has been rebuilt. A new enlarged experimental hall with a flight path of up to 10 m is available for neutron time-of-flight experiments in the fast energy range from about 50 keV to 10 MeV. nELBE is intended to deliver nuclear data of fast neutron nuclear interactions e.g. for the transmutation of nuclear waste and improvement of neutron physical simulations of innovative nuclear systems. The experimental programme consists of transmission measurements of neutron total cross sections, elastic and inelastic scattering cross section measurements, and neutron induced fission cross sections. The inelastic scattering to the first few excited states in 56Fe was investigated by measuring the gamma production cross section with an HPGe detector. The neutron induced fission of 242Pu was studied using fast ionisation chambers with large homogeneous actinide deposits.

Gamma-induced Positron Spectroscopy (GiPS) at a superconducting electron linear accelerator

Energy Technology Data Exchange (ETDEWEB)

Butterling, Maik, E-mail: maik.butterling@googlemail.com [Martin-Luther University, Dept. of Physics, 06099 Halle (Germany); Institute of Radiation Physics, Helmholtz-Zentrum, Dresden-Rossendorf, P.O. Box 510119, 01314 Dresden (Germany); Anwand, Wolfgang; Cowan, Thomas E.; Hartmann, Andreas [Institute of Radiation Physics, Helmholtz-Zentrum, Dresden-Rossendorf, P.O. Box 510119, 01314 Dresden (Germany); Jungmann, Marco; Krause-Rehberg, Reinhard [Martin-Luther University, Dept. of Physics, 06099 Halle (Germany); Krille, Arnold; Wagner, Andreas [Institute of Radiation Physics, Helmholtz-Zentrum, Dresden-Rossendorf, P.O. Box 510119, 01314 Dresden (Germany)

2011-11-15

A new and unique setup for Positron Annihilation Spectroscopy has been established and optimized at the superconducting linear electron accelerator ELBE at Helmholtz-Zentrum Dresden-Rossendorf (Germany). The intense, pulsed (26 MHz) photon source (bremsstrahlung with energies up to 16 MeV) is used to generate positrons by means of pair production throughout the entire sample volume. Due to the very short gamma bunches (< 5 ps temporal length), the facility for Gamma-induced Positron Spectroscopy (GiPS) is suitable for positron lifetime spectroscopy using the accelerator's radiofrequency as time reference. Positron lifetime and Doppler broadening Spectroscopy are employed by a coincident measurement (Age-Momentum Correlation) of the time-of-arrival and energy of the annihilation photons which in turn significantly reduces the background of scattered photons resulting in spectra with high signal to background ratios. Simulations of the setup using the GEANT4 framework have been performed to yield optimum positron generation rates for various sample materials and improved background conditions.

Nuclear deformation and neutron excess as competing effects for dipole strength in the pygmy region.

Science.gov (United States)

Massarczyk, R; Schwengner, R; Dönau, F; Frauendorf, S; Anders, M; Bemmerer, D; Beyer, R; Bhatia, C; Birgersson, E; Butterling, M; Elekes, Z; Ferrari, A; Gooden, M E; Hannaske, R; Junghans, A R; Kempe, M; Kelley, J H; Kögler, T; Matic, A; Menzel, M L; Müller, S; Reinhardt, T P; Röder, M; Rusev, G; Schilling, K D; Schmidt, K; Schramm, G; Tonchev, A P; Tornow, W; Wagner, A

2014-02-21

The electromagnetic dipole strength below the neutron-separation energy has been studied for the xenon isotopes with mass numbers A=124, 128, 132, and 134 in nuclear resonance fluorescence experiments using the γELBE bremsstrahlung facility at Helmholtz-Zentrum Dresden-Rossendorf and the HIγS facility at Triangle Universities Nuclear Laboratory Durham. The systematic study gained new information about the influence of the neutron excess as well as of nuclear deformation on the strength in the region of the pygmy dipole resonance. The results are compared with those obtained for the chain of molybdenum isotopes and with predictions of a random-phase approximation in a deformed basis. It turned out that the effect of nuclear deformation plays a minor role compared with the one caused by neutron excess. A global parametrization of the strength in terms of neutron and proton numbers allowed us to derive a formula capable of predicting the summed E1 strengths in the pygmy region for a wide mass range of nuclides.

Measurement of the inelastic neutron scattering cross section of 56Fe

Directory of Open Access Journals (Sweden)

Nolte R.

2010-10-01

Full Text Available At the superconducting electron linear accelerator ELBE at Forschungszentrum Dresden-Rossendorf the neutron time-of-flight facility nELBE has become operational. Fast neutrons in the energy range from 200 keV to 10 MeV are produced by the pulsed electron beam from ELBE impinging on a liquid lead circuit as a radiator. The short beam pulses of 10 ps provide the basis for an excellent time resolution for neutron time-of-flight experiments, giving an energy resolution of about <1% at 1 MeV with a short flight path of 5 m. By means of a “double-time-of-flight” setup the (n,nâγ cross section to the first excited state of 56Fe has been measured over the whole energy range without knowledge about cross sections of higher-lying levels. Plastic scintillators were used to detect the inelastically scattered neutron and BaF2 detectors to detect the correlated γ-ray.

Annual report 2012. Institute of Resource Ecology

Energy Technology Data Exchange (ETDEWEB)

Brendler, Vinzenz (ed.)

2013-09-01

The Institute of Resource Ecology (IRE) is one of the currently eight institutes of the Helmholtz-Zentrum Dresden-Rossendorf (HZDR). The research activities are fully integrated into the program ''Nuclear Safety Research'' of the Helmholtz Association and focused on the topics ''Safety of Nuclear Waste Disposal'' and ''Safety Research for Nuclear Reactors''. With the integration of the division of ''Reactor Safety'' from the former ''Institute of Safety Research'' nuclear research at HZDR is now mainly concentrated within this institute. In addition, various activities have been started investigating chemical and environmental aspects of processing and recycling of strategic metals, namely rare earth elements. Here, a knowledge transfer from the nuclear to the non-nuclear community, branching thermodynamics and spectroscopy, has been established. This also strengthens links to the recently established ''Helmholtz-Institute Freiberg for Resource Technology''.

Evidence for shape coexistance in 81,83Kr

International Nuclear Information System (INIS)

Kemnitz, P.; Doering, J.; Funke, L.; Winter, G.; Hildingsson, L.; Jerrestam, D.; Johnson, A.; Lindblad, Th.

1984-01-01

In the course of systematic investication of few-particle and collective states in the mass 80 region, the excitations in 81 , 83 Kr have been studied in-beam via (α,3n) reactions. Most of the data were derived from experiments at the Stockholm cyclotron, where coincidence relations, angular distributions, relative excitation functions and the linear polarization of the γ-rays were measured. To obtain precise data on the Doppler shift (DSA method) of the γ-rays, the spectra at 30 deg and 150 deg and, respectively, at 45 deg and 135 deg relative to the beam axis were measured alternatingly. Since DSA data are most reliable for the highest levels reached with a certain beam energy, additional measurements were performed at the Rossendorf cyclotron using α-particles of 27 MeV which excite lower spin states than the 42 MeV α-particles used in the main part of the experiments

Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Ion Beam Physics and Materials Research. Annual report 2010

International Nuclear Information System (INIS)

Borany, J. von; Fassbender, J.; Heera, V.; Helm, M.

2011-01-01

The following topics are dealt with: Carrier profiling of individual Si nanowires by scanning spreading resistance microscopy, observation of the intraexciton Autler-Townes effect in GaAs/AlGaAs semiconductor quantum wells, terahertz activated luminescence of trapped carriers in InGaAs/GaAs quantum dots, a microwave enhanced silicon light emitting pn-diode, on-chip superconductivity via gallium overdoping of silicon, sculpting nanoscale precipitation patterns in nanocomposite thin films via hyperthermal ion deposition, establishing the mechanism of thermally induced degradation of ZnO:Al electrical properties using synchrotron radiation, determination of the saturation magnetization of ion irradiated Py/Ta samples using polar magneto-optical Kerr effect and ferromagnetic resonance, the importance of hole concentration in establishing carrier-mediated ferromagnetism in Mn doped Ge, pyramidal pits created by single highly charged ions in BaF 2 single crystals, optical properties of silver nanowire arrays with 35 nm periodicity. (HSI)

Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Ion Beam Physics and Materials Research. Annual report 2010

Energy Technology Data Exchange (ETDEWEB)

Borany, J. von; Fassbender, J.; Heera, V.; Helm, M. (eds.)

2011-10-26

The following topics are dealt with: Carrier profiling of individual Si nanowires by scanning spreading resistance microscopy, observation of the intraexciton Autler-Townes effect in GaAs/AlGaAs semiconductor quantum wells, terahertz activated luminescence of trapped carriers in InGaAs/GaAs quantum dots, a microwave enhanced silicon light emitting pn-diode, on-chip superconductivity via gallium overdoping of silicon, sculpting nanoscale precipitation patterns in nanocomposite thin films via hyperthermal ion deposition, establishing the mechanism of thermally induced degradation of ZnO:Al electrical properties using synchrotron radiation, determination of the saturation magnetization of ion irradiated Py/Ta samples using polar magneto-optical Kerr effect and ferromagnetic resonance, the importance of hole concentration in establishing carrier-mediated ferromagnetism in Mn doped Ge, pyramidal pits created by single highly charged ions in BaF{sub 2} single crystals, optical properties of silver nanowire arrays with 35 nm periodicity. (HSI)

IRPhE/RRR-SEG, Reactor Physics Experiments from Fast-Thermal Coupled Facility

International Nuclear Information System (INIS)

Weiss, Frank-Peter; Dietze, Klaus; Jacqmin, Robert; Ishikawa, Makoto

2003-01-01

1 - Description: The RRR-SEG-experiments have been performed to check neutron data of the most important reactor materials, especially of fission product nuclides, fuel isotopes and structural materials. The measured central reactivity worths (CRW) of small samples were compared with calculated values. These C/E-ratios have been used then for data corrections or in adjustment procedures. The reactor RRG-SEG (at RC Rossendorf / Germany) was a fast-thermal coupled facility of zero power. The annular thermal drivers were filled by fuel assemblies and moderated by water. The inner insertion lattices were loaded with pellets of fuel and other materials producing the fast neutron flux. The characteristics of the neutron and adjoint spectra were obtained by special arrangements of these pellets in unit cells. In this way, a hard or soft neutron spectrum or a special energy behavior of the adjoint function could be reached. The samples were moved by means of tubes to the central position (pile-oscillation technique). The original information about the facility and measurements is compiled in Note Technique SPRC/LEPh/93-230 (SEG) The SEG experiments are considered 'clean' integral experiments, simple and clear in geometry and well suited for calculation. In all SEG configurations only a few materials were used, most of these were standards. Due to the designed adjoint function (energy-independent or monotonously rising), the capture or scattering effect was dominant, convenient to check separately capture or scattering data. At first, analyses of the experiments have been performed in Rossendorf. Newer analyses were done later in Cadarache / CEA France using the European scheme for reactor calculation JEF-2.2 / ECCO / ERANOS (see Note Techniques and JEF/DOC-746). Furthermore, re-analyses were performed in O-arai / JNC Japan with the JNC standard route JENDL-3.2 / SLAROM / CITATION / PERKY. Results obtained with both code systems and different data evaluations (JEF-2.2 and

Modeling of radial gas fraction profiles for bubble flow in vertical pipes

Energy Technology Data Exchange (ETDEWEB)

Lucas, D.; Krepper, E.; Prasser, H.-M. [Forschungszentrum Rossendorf e.V., Institute of Safety Research, Dresden (Germany)

2001-07-01

The paper presents a method for the prediction of radial gas fraction profiles from a given bubble size distribution. The method is based on the assumption of the equilibrium of the forces acting on a bubble perpendicularly to the flow direction. Assuming a large number of bubble size classes radial distributions are calculated separately for all bubble classes. The sum of these distributions is the radial profile of the gas fraction. The results of the model are compared with experimental data for a number of gas and liquid volume flow rates. The experiments were performed at a vertical test loop (inner diameter 50 mm) in FZ-Rossendorf using a wire mesh sensor. The sensor enables the determination of void distributions in the cross section of the loop. A special evaluation procedure supplies bubble size distributions as well as local distributions of bubbles within a predefined interval of bubble sizes. There is a good agreement between experimental and calculated data. In particular the change from wall peaking to core peaking is well predicted. (authors)

High Brightness Electron Guns for Next-Generation Light Sources and Accelerators

International Nuclear Information System (INIS)

H. Bluem; M.D. Cole; J. Rathke; T. Schultheiss; A.M.M. Todd; I. Ben-Zvi; T. Srinivasan-Rao; P. Colestock; D.C. Nguyen; R.L. Wood; L. Young; D. Janssen; J. Lewellen; G. Neil; H.L. Phillips; J.P. Preble

2004-01-01

Advanced Energy Systems continues to develop advanced electron gun and injector concepts. Several of these projects have been previously described, but the progress and status of each will be updated. The project closest to completion is an all superconducting RF (SRF) gun, being developed in collaboration with the Brookhaven National Laboratory, that uses the niobium of the cavity wall itself as the photocathode material. This gun has been fabricated and will shortly be tested with beam. The cavity string for a closely-coupled DC gun and SRF cavity injector that is expected to provide beam quality sufficient for proposed ERL light sources and FELs will be assembled at the Jefferson Laboratory later this year. We are also collaboration with Los Alamos on a prototype CW normal-conducting RF gun with similar performance, that will undergo thermal testing in late 2004. Another CW SRF gun project that uses a high quantum efficiency photocathode, similar to the FZ-Rossendorf approach, has just begun. Finally, we will present the RF design and cold test results for a fully axisymmetric, ultra-high-brightness x-band RF gun

Determination of the electromagnetic dipole strength distribution in medium-heavy atomic nuclei by means of nuclear resonance fluorescence; Bestimmung der elektromagnetischen Dipolstaerkeverteilung in mittelschweren Atomkernen mittels Kernresonanzfluoreszenz

Energy Technology Data Exchange (ETDEWEB)

Massarczyk, Ralph Jens

2011-01-17

During the last hundred years several models were developed to describe the configuration of nuclei. These models have to make predictions, which should be comparable with experiments. As a standard type of experiment the nuclear resonance fluorescence was established. A nucleus is excited by irradiation with photons. By emitting one or more photons the nucleus decays back to the ground state. With this method it is possible to measure energy levels and to determine the strength of their excitation. A continuum of unresolved peaks gives additional strength. The existing setup at the linear electron accelerator ELBE of the Forschungszentrum Dresden-Rossendorf uses bremsstrahlung, produced as a secondary beam in a thin Niobium foil. During the years 2008/09 experiments on the nuclei of {sup 86}Kr and {sup 136}Ba took place there. In this work they will be analyzed. Photon flux and efficiency determination have been done as well as simulations on detector response and non-nuclear scattered background events. For this purpose the GEANT4 package was used. Finally the resulting cross sections were corrected for branching and feeding.

Experiments on the formation of titanium-44 in supernovae; Experimente zur Entstehung von Titan-44 in Supernovae

Energy Technology Data Exchange (ETDEWEB)

Schmidt, Konrad

2012-11-01

In this thesis the astrophysically interesting resonance triplet of the {sup 40}Ca({alpha},{gamma}){sup 44}Ti reaction at 4.5 MeV has been studied. For this purpose energies of proton and {alpha} beams provided by 3 MV Tandetron at Helmholtz-Zentrum Dresden-Rossendorf have been calibrated. Excitation functions of energy regions near the resonances and in-beam spectra of four different targets have been measured. The {sup 40}Ca(p,{gamma}){sup 41}Sc reaction has been used to scan the structure of the activated targets. Afterwards their activity has been measured in the underground laboratory Felsenkeller Dresden. Hence the sum of resonance strengths at laboratory {alpha} energies of 4497 and 4510 keV of (12.8{+-}2.3) eV has been determined as well as the sum of the total triplet strength, including 4523 keV, of (12.0{+-}2.0) eV. In the case of the first resonance, the uncertainty was decreased from 19% to 18 %. Furthermore the results of this work establish a basis for reaching much lower uncertainties in the future.

Modeling of radial gas fraction profiles for bubble flow in vertical pipes

International Nuclear Information System (INIS)

Lucas, D.; Krepper, E.; Prasser, H.-M.

2001-01-01

The paper presents a method for the prediction of radial gas fraction profiles from a given bubble size distribution. The method is based on the assumption of the equilibrium of the forces acting on a bubble perpendicularly to the flow direction. Assuming a large number of bubble size classes radial distributions are calculated separately for all bubble classes. The sum of these distributions is the radial profile of the gas fraction. The results of the model are compared with experimental data for a number of gas and liquid volume flow rates. The experiments were performed at a vertical test loop (inner diameter 50 mm) in FZ-Rossendorf using a wire mesh sensor. The sensor enables the determination of void distributions in the cross section of the loop. A special evaluation procedure supplies bubble size distributions as well as local distributions of bubbles within a predefined interval of bubble sizes. There is a good agreement between experimental and calculated data. In particular the change from wall peaking to core peaking is well predicted. (authors)

Experience with the transport and storage casks CASTOR (registered) MTR 2 for spent nuclear fuel assemblies from research reactors

Energy Technology Data Exchange (ETDEWEB)

Jack, Allen; Rettenbacher, Katharina; Skrzyppek, Juergen [GNS Gesellschaft fuer Nuklear-Service mbH, Essen (Germany)

2011-07-01

The CASTOR (registered) MTR 2 cask was designed and manufactured by the company GNS during the 1990's for the transport and interim storage of spent nuclear fuel assemblies from various types of research reactors. Casks of this type have been used at the VKTA Research Centre in Rossendorf near Dresden, Germany as well as at the European Commission's Joint Research Centre at Petten and at the HOR reactor at Delft in the Netherlands. A total of 24 units have been used for the functions of transport and storage with various spent fuel types (VVER, HFR-HEU, and HOR-HEU) for more than ten years now. This type of packaging for radioactive material is a member of the CASTOR (registered) family of spent nuclear fuel casks used worldwide. Over 1000 units are loaded and in storage in Europe, Asia, Africa and North America. This paper presents the experience from the use of the casks for transport and storage in the past, as well as the prospects for the future. (author)

High-resolution ion-implanted silicon detectors

International Nuclear Information System (INIS)

von Borany, J.; Schmidt, B.

1985-01-01

An account is given of the properties of silicon detectors developed at the Central Institute of Nuclear Research of the Academy of Sciences of the German Democratic Republic (Rossendorf) and made by a special planar technology using ion implantation, anodic oxidation, thermal oxidation in an oxygen atmosphere containing HCl, and annealing by pulses of 10--20 msec duration. The resolution for α particles of 5.5 MeV energy was 11.2 keV (active area A 2 ). The detectors were characterized by a low intrinsic noise (< or =5 keV), so that they could be used for spectrometry of low-energy electrons (E/sub e/< or =250 keV). In a certain range of energies (E/sub x/ = 15--60 keV) it was possible to use these detectors for spectrometry of x rays at room temperature. Examples and results of applications of detectors in radiation chemistry (investigations of backscattering of particles and nuclear reaction spectroscopy) are given. The feasibility of annealing of radiation defects in such detectors after irradiation with a large dose of charged particles is considered

Unsteady single-phase natural circulation flow mixing prediction using CATHARE three-dimensional capabilities

Energy Technology Data Exchange (ETDEWEB)

Salah, Anis Bousbia; Vlassenbroeck, Jacques [Bel V - Subsidiary of the Belgian Federal Agency for Nuclear Contro, Brussels (Belize)

2017-04-15

Coolant mixing under natural circulation flow regime constitutes a key parameter that may play a role in the course of an accidental transient in a nuclear pressurized water reactor. This issue has motivated some experimental investigations carried out within the OECD/NEA PKL projects. The aim was to assess the coolant mixing phenomenon in the reactor pressure vessel downcomer and the core lower plenum under several asymmetric steady and unsteady flow conditions, and to provide experimental data for code validations. Former studies addressed the mixing phenomenon using, on the one hand, one-dimensional computational approaches with cross flows that are not fully validated under transient conditions and, on the other hand, expensive computational fluid dynamic tools that are not always justified for large-scale macroscopic phenomena. In the current framework, an unsteady coolant mixing experiment carried out in the Rossendorf coolant mixing test facility is simulated using the three-dimensional porous media capabilities of the thermal–hydraulic system CATHARE code. The current study allows highlighting the current capabilities of these codes and their suitability for reproducing the main phenomena occurring during asymmetric transient natural circulation mixing conditions.

A new data-processing approach to study particle motion using ultrafast X-ray tomography scanner: case study of gravitational mass flow

Science.gov (United States)

Waktola, Selam; Bieberle, Andre; Barthel, Frank; Bieberle, Martina; Hampel, Uwe; Grudzień, Krzysztof; Babout, Laurent

2018-04-01

In most industrial products, granular materials are often required to flow under gravity in various kinds of silo shapes and usually through an outlet in the bottom. There are several interrelated parameters which affect the flow, such as internal friction, bulk and packing density, hopper geometry, and material type. Due to the low-spatial resolution of electrical capacitance tomography or scanning speed limitation of standard X-ray CT systems, it is extremely challenging to measure the flow velocity and possible centrifugal effects of granular materials flow effectively. However, ROFEX (ROssendorf Fast Electron beam X-ray tomography) opens new avenues of granular flow investigation due to its very high temporal resolution. This paper aims to track particle movements and evaluate the local grain velocity during silo discharging process in the case of mass flow. The study has considered the use of the Seramis material, which can also serve as a type of tracer particles after impregnation, due to its porous nature. The presented novel image processing and analysis approach allows satisfyingly measuring individual particle velocities but also tracking their lateral movement and three-dimensional rotations.

Analysis of transients for NPP with VVER-440 using the code SiTAP

International Nuclear Information System (INIS)

Kalinenko, V.

1994-06-01

The report contains analysis of transients ''Loop connection'' and ''Steam generator tube rupture'' for nuclear power plants (NPP) with VVER-440. To obtain more detailed information about NPP's dynamic characteristics, various variants of initial and boundary conditions are considerd. Calculation of these transients was performed using the SiTAP code developed at the Nuclear Safety Institute of the Russian Research Centre ''Kurchatov Institute''. SiTAP code is a multifunctional computer tool for fast analysis of transient and accidental processes of VVER type reactors for engineers working in the field of NPP dynamics. SiTAP can be used form comparative analysis of several variants of accident scenarios to find out the conditions leading to most serious consequences from a safety point of view. In such cases, additional analyses using best-estimate codes should be carried out. The results of SiTAP for a faulty loop connection leading to a boron dilution accident are intended to be used as boundary conditions for a more detailed anlaysis with the aid of the three-dimensional reactor core model DYN3D, developed in the Research Centre Rossendorf for the simulation of reactivity initiated accidents. (orig.)

Annual Report 2010. Institute of Radiochemistry

Energy Technology Data Exchange (ETDEWEB)

Bernhard, G. (ed.)

2011-10-26

The Institute of Radiochemistry is one of the six research institutes of the Helmholtz center Dresden-Rossendorf. The report covers contributions in two parts. Part 1; long-lived radionuclides in biosystems: Several contributions concern the determination of formation and structures of various uranium, americium, and curium complexes with relevant organic and inorganic ligands. First results about the dependency of uranium(VI) complexation with small organic ligands at elevated temperatures were achieved. New insights in the mechanisms of luminescence quenching of uranyl complexes by density functional theory calculations are reported. Bacteria, algae, and fungi can influence the mobilization or immobilization of heavy metals in water and soils. Part II: long-lived radionuclides at permanent disposal sites. Several contributions report research on the behavior of biofilms in uranium contaminated sites. To describe the aqueous transport of actinides and other long-lived radionuclides the dominating processes on the liquid/solid interfaces must be considered. Interesting results about the sorption and surface complexation of different metals (long-lived radionuclides) during interaction with various mineral surfaces, and colloids were achieved. Substantial progress was made on knowledge about the visualization and quantification of fluid flow in salt rock formations by using positron emission tomography.

A technical system to improve the operational monitoring of the Zaporozhye nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Beyer, M; Carl, H; Nowak, K [Technischer Ueberwachungsverein Rheinland, Koeln (Germany). Inst. for Nuclear Engineering and Radiation Protection; Schumann, P; Seidel, A; Weiss, F P; Zschau, J

1998-10-01

As part of the programme implemented by the German Ministry of Environment, Nature Conservation and Reactor Safety to cooperate with the Central and Eastern European States (CEES) and the Commonwealth of Independent States (CIS) in the area of nuclear safety, a technical system to improve operational monitoring has been designed, specified and established since 1992 as a pilot project in the Zaporozhye/Ukraine nuclear power plant by Forschungszentrum Rossendorf and Technischer Ueberwachungsverein Rheinland with a significant contribution from the State Scientific and Technical Centre of the Ukrainian supervisory authority. The technical system complements existing operational checking and monitoring facilities by including modern means of information technology. It enables a continuous monitoring of the state of unit 5 in normal operation and in cases of anomalies or incidents so that when recognisable deviations from the regular plant operation occur, the Ukrainian supervisory authority can immediately inquire and if necessary impose conditions on the operator. The radiological and meteorological parameters at the nuclear power plant location are monitored to the extent necessary to assess the current radiation situation and to implement efficient emergency management measures. (orig.)

High-repetition-rate laser-proton acceleration from a condensed hydrogen jet

Energy Technology Data Exchange (ETDEWEB)

Obst, Lieselotte; Zeil, Karl; Metzkes, Josefine; Schlenvoigt, Hans-Peter; Rehwald, Martin; Sommer, Philipp; Brack, Florian; Schramm, Ulrich [Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany); Goede, Sebastian; Gauthier, Maxence; Roedel, Christian; MacDonald, Michael; Schumaker, William; Glenzer, Siegfried [SLAC National Accelerator Laboratory, Stanford (United States)

2016-07-01

Applications of laser-accelerated protons demand a stable source of energetic particles at high repetition rates. We present the results of our experimental campaign in cooperation with MEC/SLAC at the 10Hz Ti:Sa laser Draco of Helmholtz-Zentrum Dresden-Rossendorf (HZDR), employing a pure condensed hydrogen jet as a renewable target. Draco delivers pulses of 30 fs and 5 J at 800 nm, focused to a 3 μm spot by an F/2.5 off-axis parabolic mirror. The jet's nominal electron density is approximately 30 times the critical density and its thickness is 2 μm, 5 μm or 10 μm, depending on the applied aperture on the source. Ion diagnostics reveal mono-species proton acceleration in a solid angle of at least +/-45 with respect to the incoming laser beam, with maximum energies of around 5 MeV. The expanding jet could be monitored on-shot with a temporally synchronized probe beam perpendicular to the pump laser axis. Recorded probe images resemble those of z-pinch experiments with metal wires and indicate an m=0 instability in the plasma.

A technical system to improve the operational monitoring of the Zaporozhye nuclear power plant

International Nuclear Information System (INIS)

Beyer, M.; Carl, H.; Nowak, K.; Schumann, P.; Seidel, A.; Weiss, F.P.; Zschau, J.

1998-01-01

As part of the programme implemented by the German Ministry of Environment, Nature Conservation and Reactor Safety to cooperate with the Central and Eastern European States (CEES) and the Commonwealth of Independent States (CIS) in the area of nuclear safety, a technical system to improve operational monitoring has been designed, specified and established since 1992 as a pilot project in the Zaporozhye/Ukraine nuclear power plant by Forschungszentrum Rossendorf and Technischer Ueberwachungsverein Rheinland with a significant contribution from the State Scientific and Technical Centre of the Ukrainian supervisory authority. The technical system complements existing operational checking and monitoring facilities by including modern means of information technology. It enables a continuous monitoring of the state of unit 5 in normal operation and in cases of anomalies or incidents so that when recognisable deviations from the regular plant operation occur, the Ukrainian supervisory authority can immediately inquire and if necessary impose conditions on the operator. The radiological and meteorological parameters at the nuclear power plant location are monitored to the extent necessary to assess the current radiation situation and to implement efficient emergency management measures. (orig.)

Experimental investigation and CFD simulation of horizontal stratified two-phase flow phenomena

International Nuclear Information System (INIS)

Vallee, Christophe; Hoehne, Thomas; Prasser, Horst-Michael; Suehnel, Tobias

2008-01-01

For the investigation of stratified two-phase flow, two horizontal channels with rectangular cross-section were built at Forschungszentrum Dresden-Rossendorf (FZD). The channels allow the investigation of air/water co-current flows, especially the slug behaviour, at atmospheric pressure and room temperature. The test-sections are made of acrylic glass, so that optical techniques, like high-speed video observation or particle image velocimetry (PIV), can be applied for measurements. The rectangular cross-section was chosen to provide better observation possibilities. Moreover, dynamic pressure measurements were performed and synchronised with the high-speed camera system. CFD post-test simulations of stratified flows were performed using the code ANSYS CFX. The Euler-Euler two fluid model with the free surface option was applied on grids of minimum 4 x 10 5 control volumes. The turbulence was modelled separately for each phase using the k-ω-based shear stress transport (SST) turbulence model. The results compare very well in terms of slug formation, velocity, and breaking. The qualitative agreement between calculation and experiment is encouraging and shows that CFD can be a useful tool in studying horizontal two-phase flow

Experimental investigation and CFD simulation of horizontal stratified two-phase flow phenomena

International Nuclear Information System (INIS)

Vallee, Christophe; Hohne, Thomas; Prasser, Horst-Michael; Suhnel, Tobias

2007-01-01

For the investigation of stratified two-phase flow, two horizontal channels with rectangular cross-section were built at Forschungszentrum Rossendorf. The channels allow the investigation of air/water co-current flows, especially the slug behaviour, at atmospheric pressure and room temperature. The test-sections are made of acrylic glass, so that optical techniques, like high-speed video observation or particle image velocimetry (PIV), can be applied for measurements. The rectangular cross-section was chosen to provide better observation possibilities. Moreover, dynamic pressure measurements were performed and synchronized with the high-speed camera system. CFD post test simulations of stratified flows were performed using the code ANSYS CFX. The Euler- Euler two fluid model with the free surface option was applied on grids of minimum 4.10 5 control volumes. The turbulence was modelled separately for each phase using the k-ω based shear stress transport (SST) turbulence model. The results compare very well in terms of slug formation, velocity, and breaking. The qualitative agreement between calculation and experiment is encouraging and shows that CFD can be a useful tool in studying horizontal two-phase flow. (authors)

Experimental investigation and CFD simulation of horizontal stratified two-phase flow phenomena

Energy Technology Data Exchange (ETDEWEB)

Vallee, Christophe [Forschungszentrum Dresden-Rossendorf e.V., Dresden (Germany)], E-mail: c.vallee@fzd.de; Hoehne, Thomas; Prasser, Horst-Michael; Suehnel, Tobias [Forschungszentrum Dresden-Rossendorf e.V., Dresden (Germany)

2008-03-15

For the investigation of stratified two-phase flow, two horizontal channels with rectangular cross-section were built at Forschungszentrum Dresden-Rossendorf (FZD). The channels allow the investigation of air/water co-current flows, especially the slug behaviour, at atmospheric pressure and room temperature. The test-sections are made of acrylic glass, so that optical techniques, like high-speed video observation or particle image velocimetry (PIV), can be applied for measurements. The rectangular cross-section was chosen to provide better observation possibilities. Moreover, dynamic pressure measurements were performed and synchronised with the high-speed camera system. CFD post-test simulations of stratified flows were performed using the code ANSYS CFX. The Euler-Euler two fluid model with the free surface option was applied on grids of minimum 4 x 10{sup 5} control volumes. The turbulence was modelled separately for each phase using the k-{omega}-based shear stress transport (SST) turbulence model. The results compare very well in terms of slug formation, velocity, and breaking. The qualitative agreement between calculation and experiment is encouraging and shows that CFD can be a useful tool in studying horizontal two-phase flow.

Inhomogeneous MUSIG Model - a population balance approach for polydispersed bubbly flows

International Nuclear Information System (INIS)

Frank, T.; Zwart, P.J.; Shi, J.; Krepper, E.; Lucas, D.; Rohde, U.

2005-01-01

Many flow regimes in Nuclear Reactor Safety (NRS) Research are characterized by multiphase flows, with one phase being a continuous liquid and the other phase consisting of gas or vapour of the liquid phase. In the range of low to intermediate volume fraction of the gaseous phase the multiphase flow under consideration is a bubbly or slug flow, where the disperse phase is characterized by an evolving bubble size distribution due to bubble breakup and coalescence processes. The paper presents a generalized inhomogeneous Multiple Size Group (MUSIG) Model. Within this model the disperse gaseous phase is divided into N inhomogeneous velocity groups (phases) and each of these groups is subdivided into M bubble size classes. Bubble breakup and coalescence processes between all bubble size classes are taken into account by appropriate models. The derived inhomogeneous MUSIG model has been validated against experimental data from the TOPFLOW test facility at the Research Center Rossendorf (FZR). Comparisons of gas volume fraction and velocity profiles with TOPFLOW-074 test case data are provided, showing the applicability and accuracy of the model for polydispersed bubbly flow in large diameter vertical pipe flow. (author)

Fabrication, Tuning, Treatment and Testing of Two 3.5 Cell Photo-Injector Cavities for the ELBE Linac

International Nuclear Information System (INIS)

Arnold, A.; Murcek, P.; Teichert, J.; Xiang, R.; Eremeev, G. V.; Kneisel, P.; Stirbet, M.; Turlington, L.

2011-01-01

As part of a CRADA (Cooperative Research and Development Agreement) between Helmholtz-Zentrum Dresden-Rossendorf (HZDR) and Thomas Jefferson Lab National Accelerator Facility (TJNAF) we have fabricated and tested two 1.3 GHz 3.5 cell photo-injector cavities from polycrystalline RRR niobium and large grain RRR niobium, respectively. The cavity with the better performance will replace the presently used injector cavity in the ELBE linac. The cavities have been fabricated and pre-tuned at TJNAF, while the more sophisticated final field tuning, the adjustment of the external couplings and the field profile measurement of transverse electric modes for RF focusing was done at HZDR. The following standard surface treatment and the vertical test was carried out at TJNAF's production facilities. A major challenge turned out to be the rinsing of the cathode cell, which has small opening (O-slash10mm) to receive the cathode stalk. Another unexpected problem encountered after etching, since large visible defects appeared in the least accessible cathode cell. This contribution reports about our experiences, initial results and the on-going diagnostic work to understand and fix the problems

Numerical investigations for insulation particle transport phenomena in water flow

International Nuclear Information System (INIS)

Krepper, E.; Grahn, A.; Alt, S.; Kaestner, W.; Kratzsch, A.; Seeliger, A.

2005-01-01

The investigation of insulation debris generation, transport and sedimentation gains importance regarding the reactor safety research for PWR and BWR considering the long term behaviour of emergency core coolant systems during all types of LOCA. The insulation debris released near the break during LOCA consists of a mixture of very different particles concerning size, shape, consistence and other properties. Some fraction of the released insulation debris will be transported into the reactor sump where it may affect emergency core cooling. Open questions of generic interest are e.g. the sedimentation of the insulation debris in a water pool, possible re-suspension, transport in the sump water flow, particle load on strainers and corresponding difference pressure. A joint research project in cooperation with Institute of Process Technology, Process Automation and Measuring Technology (IPM) Zittau deals with the experimental investigation and the development of CFD models for the description of particle transport phenomena in coolant flow. While experiments are performed at the IPM-Zittau, theoretical work is concentrated at Forschungszentrum Rossendorf. In the present paper the basic concepts for CFD modelling are described and first results including feasibility studies are shown. During the ongoing work further results are expected. (author)

Uranium, plutonium and co

International Nuclear Information System (INIS)

Sauerbrey, Roland; Joehnk, Peter

2016-01-01

To date there is no repository facility for highly radioactive and heat-generating waste in Germany. This politically ''hot'' topic is undeniably a very big, urgent problem in our society. The Helmholtz Association of German Research Centers is dedicated to developing scientific solutions for such issues. It looks back on 20 years of history: In 1995 the loosely organized collective bearing the name ''Working Association of Large-Scale Research Institutes'' (Arbeitsgemeinschaft der Grossforschungseinrichtungen) became an association of now 18 research centers. These centers collectively work in a total of six research areas. While the HZDR has only belonged to the largest research association in Germany since 2011, repository research was already on the agenda way back when the Rossendorf research center established itself in 1992 after the fall of the Berlin Wall. A good enough reason to examine the results from about 20 years of repository research in Dresden in more detail. In this issue of ''discovered'' we will take an inside look at radiochemical, radiogeological, and microbiological labs, look over the shoulders of researchers using the ''Rossendorf Beamline'' at the European Synchrotron Radiation Facility in Grenoble, and descend hundreds of meters into Finnish, Swedish, and Swiss research labs. How do ''uranium, plutonium, and co.'' react with mineral surfaces in environments that are low in oxygen or watery? How do they interact with microorganisms deep underground? And how can host rock or other materials be used as technical barriers to prevent the spread of radioactive substances? In order to answer these and further questions, the researchers of the HZDR use a wide range of spectroscopic methods. They expose test samples to lasers, infrared light, and X-rays or use the fluorescent properties of certain compounds to learn about the behavior of actinides

Uranium, plutonium and co

Energy Technology Data Exchange (ETDEWEB)

Sauerbrey, Roland; Joehnk, Peter (eds.)

2016-04-15

To date there is no repository facility for highly radioactive and heat-generating waste in Germany. This politically ''hot'' topic is undeniably a very big, urgent problem in our society. The Helmholtz Association of German Research Centers is dedicated to developing scientific solutions for such issues. It looks back on 20 years of history: In 1995 the loosely organized collective bearing the name ''Working Association of Large-Scale Research Institutes'' (Arbeitsgemeinschaft der Grossforschungseinrichtungen) became an association of now 18 research centers. These centers collectively work in a total of six research areas. While the HZDR has only belonged to the largest research association in Germany since 2011, repository research was already on the agenda way back when the Rossendorf research center established itself in 1992 after the fall of the Berlin Wall. A good enough reason to examine the results from about 20 years of repository research in Dresden in more detail. In this issue of ''discovered'' we will take an inside look at radiochemical, radiogeological, and microbiological labs, look over the shoulders of researchers using the ''Rossendorf Beamline'' at the European Synchrotron Radiation Facility in Grenoble, and descend hundreds of meters into Finnish, Swedish, and Swiss research labs. How do ''uranium, plutonium, and co.'' react with mineral surfaces in environments that are low in oxygen or watery? How do they interact with microorganisms deep underground? And how can host rock or other materials be used as technical barriers to prevent the spread of radioactive substances? In order to answer these and further questions, the researchers of the HZDR use a wide range of spectroscopic methods. They expose test samples to lasers, infrared light, and X-rays or use the fluorescent properties of certain compounds to learn about the behavior of actinides

Sorption databases for increasing confidence in performance assessment - 16053

International Nuclear Information System (INIS)

Richter, Anke; Brendler, Vinzenz; Nebelung, Cordula; Payne, Timothy E.; Brasser, Thomas

2009-01-01

requires that all mineral constituents of the solid phase are characterized. Another issue is the large number of required parameters combined with time-consuming iterations. Addressing both approaches, we present two sorption databases, developed mainly by or under participation of the Forschungszentrum Dresden-Rossendorf (FZD). Both databases are implemented as relational databases, assist identification of critical data gaps and the evaluation of existing parameter sets, provide web based data search and analyses and permit the comparison of SCM predictions with K d values. RES 3 T (Rossendorf Expert System for Surface and Sorption Thermodynamics) is a digitized thermodynamic sorption database (see www.fzd.de/db/RES3T.login) and free of charge. It is mineral-specific and can therefore also be used for additive models of more complex solid phases. ISDA (Integrated Sorption Database System) connects SCM with the K d concept but focuses on conventional K d . The integrated datasets are accessible through a unified user interface. An application case, K d values in Performance Assessment, is given. (authors)

Image-Processing-Based Study of the Interfacial Behavior of the Countercurrent Gas-Liquid Two-Phase Flow in a Hot Leg of a PWR

Directory of Open Access Journals (Sweden)

Gustavo A. Montoya

2012-01-01

Full Text Available The interfacial behavior during countercurrent two-phase flow of air-water and steam-water in a model of a PWR hot leg was studied quantitatively using digital image processing of a subsequent recorded video images of the experimental series obtained from the TOPFLOW facility, Helmholtz-Zentrum Dresden-Rossendorf e.V. (HZDR, Dresden, Germany. The developed image processing technique provides the transient data of water level inside the hot leg channel up to flooding condition. In this technique, the filters such as median and Gaussian were used to eliminate the drops and the bubbles from the interface and the wall of the test section. A Statistical treatment (average, standard deviation, and probability distribution function (PDF of the obtained water level data was carried out also to identify the flow behaviors. The obtained data are characterized by a high resolution in space and time, which makes them suitable for the development and validation of CFD-grade closure models, for example, for two-fluid model. This information is essential also for the development of mechanistic modeling on the relating phenomenon. It was clarified that the local water level at the crest of the hydraulic jump is strongly affected by the liquid properties.

The system for centralized inventory keeping and ultimate disposal of radioactive waste in the former German Democratic Republic

International Nuclear Information System (INIS)

Beise, E.; Mielke, H.G.; Mueller, W.; Oppermann, U.

1991-01-01

The report explains the concept adopted by the former GDR. The system based at Morsleben, for centralized inventory keeping and management of radioactive waste is explained, refewing to the amounts of waste accrued, storage and transport of waste drums, classification and preparation of waste forms, and ultimate disposal of radioactive waste in the Morsleben repository. The report includes information on the management of special waste and spent fuel elements which cannot be stored at the Morsleben site. Most of the radioactive waste produced in the former GDR has been stored since 1979 at the Morsleben site. The waste came from the nuclear power plants (Greifswald, Rheinsberg), and from installations and institutes applying or producing radionuclides - so-called APR waste - (e.g. from the institutes at Rossendorf and Berlin-Buch, and from about 1300 other waste producers). The waste was accepted as or processed to solid waste forms, liquid waste, sealed radiation sources, and special waste; the ultimate storage techniques applied are packing of drums, backfilling, solidification of liquid waste and disposal in boreholes. Up to the end of the year 1989, the Morsleben repository received about 14000 m 3 of radioactive waste (about 40% solid waste, and about 60% liquid waste). (orig.) [de

The applicability of CFD to simulate and study the mixing process and the thermo-hydraulic consequences of a main steam line break in PWR model

Directory of Open Access Journals (Sweden)

Farkas Istvan

2017-01-01

Full Text Available This paper focuses on the validation and applicability of CFD to simulate and analyze the thermo-hydraulic consequences of a main steam line break. Extensive validation data come from experiments performed using the Rossendorf coolant mixing model facility. For the calculation, the range of 9 to 12 million hexahe¬dral cells was constructed to capture all details in the interrogation domain in the system. The analysis was performed by running a time-dependent calculation, Detailed analyses were made at different cross-sections in the system to evaluate not only the value of the maximum and minimum temperature, but also the loca¬tion and the time at which it occurs during the transient which is considered to be indicator for the quality of mixing in the system. CFD and experimental results were qualitatively compared; mixing in the cold legs with emergency core cooling systems was overestimated. This could be explained by the sensitivity to the bound¬ary conditions. In the downcomer, the experiments displayed higher mixing: by our assumption this related to the dense measurement grid (they were not modelled. The temperature distribution in the core inlet plane agreed with the measurement results. Minor deviations were seen in the quantitative comparisons: the maximum temperature difference was 2ºC.

Modeling of flashing-induced instabilities in the start-up phase of natural-circulation BWRs using the two-phase flow code FLOCAL

Energy Technology Data Exchange (ETDEWEB)

Manera, A. [Forschungszentrum Rossendorf e.V. (FZR), Institute of Safety Research, P.O.B. 510119, D-01324 Dresden (Germany) and Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands)]. E-mail: a.manera@fz-rossendorf.de; Rohde, U. [Forschungszentrum Rossendorf e.V. (FZR), Institute of Safety Research, P.O.B. 510119, D-01324 Dresden (Germany); Prasser, H.-M. [Forschungszentrum Rossendorf e.V. (FZR), Institute of Safety Research, P.O.B. 510119, D-01324 Dresden (Germany); Hagen, T.H.J.J. van der [Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands)

2005-06-01

This paper reports on the modeling and simulation of flashing-induced instabilities in natural-circulation systems, with special emphasis on natural-circulation boiling water reactors (BWRs). For the modeling the 4-equation two-phase model FLOCAL [Rohde, U., 1986. Ein teoretisches Modell fur Zweiphasen-stromungen in wassergekulthen Kernreaktoren und seine Anwendung zur Analyse des Naturumlaufs im Heizreaktor AST-500. Ph.D. dissertation, Akademie der Wissenschaften der DDR, Dresden], developed at the Forschungszentrum Rossendorf (FZR, Germany), has been used. The model allows for the liquid and vapor to be in thermal non-equilibrium and, via drift-flux models, to have different velocities. The phenomenology of the instability has been studied and the dominating physical effects have been determined. The results of the simulations have been compared qualitatively and quantitatively with experiments [Manera, A., van der Hagen, T.H.J.J., 2003. Stability of natural-circulation-cooled boiling water reactor during start up: experimental results. Nuc. Technol., 143] that have been carried out within the framework of a European project (NACUSP) on the CIRCUS facility. The facility, built at the Delft University of Technology in The Netherlands, is a water/steam 1:1 height-scaled loop of a typical natural-circulation-cooled BWR.

Fast wire-mesh sensors for gas-liquid flows - Visualisation with up to 10 000 frames per second

International Nuclear Information System (INIS)

Prasser, H.M.; Zschau, J.; Peters, D.; Pietzsch, G.; Taubert, W.; Trepte, M.

2002-01-01

A wire-mesh sensor developed by the Forschungszentrum Rossendorf produces sequences of instantaneous gas fraction distributions in a cross section at a rate of up to 10 000 frames per second and a spatial resolution of about 2-3 mm. This sensor was applied to an upwards air-liquid flow in a vertical pipe of 51.2 mm diameter. After a brief introduction of the functioning of the sensor, the paper presents results obtained in a at vertical pipe operated with an air-water mixture. Two wire-mesh sensors with a measuring matrix of 24 x 24 points (resolution 2 mm) were placed in a small axial distance behind each other. They were used to study the flow structure in the transition region from bubble to slug flow at an imaging frequency of 2 500 Hz. The two available measuring planes allowed to obtain velocity profiles of the gaseous phase. A sensor with 16 x 16 points (resolution 3 mm) was applied to visualize the transition from bubbly via churn turbulent to annular flow with 10 000 frames per second. In the churn flow region, periodic plug-like structures were found. In the annular flow the sensor is able to resolve wispy structures. (authors)

Optimization of a Two-Fluid Hydrodynamic Model of Churn-Turbulent Flow

Energy Technology Data Exchange (ETDEWEB)

Donna Post Guillen

2009-07-01

A hydrodynamic model of two-phase, churn-turbulent flows is being developed using the computational multiphase fluid dynamics (CMFD) code, NPHASE-CMFD. The numerical solutions obtained by this model are compared with experimental data obtained at the TOPFLOW facility of the Institute of Safety Research at the Forschungszentrum Dresden-Rossendorf. The TOPFLOW data is a high quality experimental database of upward, co-current air-water flows in a vertical pipe suitable for validation of computational fluid dynamics (CFD) codes. A five-field CMFD model was developed for the continuous liquid phase and four bubble size groups using mechanistic closure models for the ensemble-averaged Navier-Stokes equations. Mechanistic models for the drag and non-drag interfacial forces are implemented to include the governing physics to describe the hydrodynamic forces controlling the gas distribution. The closure models provide the functional form of the interfacial forces, with user defined coefficients to adjust the force magnitude. An optimization strategy was devised for these coefficients using commercial design optimization software. This paper demonstrates an approach to optimizing CMFD model parameters using a design optimization approach. Computed radial void fraction profiles predicted by the NPHASE-CMFD code are compared to experimental data for four bubble size groups.

E1 and M1 strength functions at low energy

Science.gov (United States)

Schwengner, Ronald; Massarczyk, Ralph; Bemmerer, Daniel; Beyer, Roland; Junghans, Arnd R.; Kögler, Toni; Rusev, Gencho; Tonchev, Anton P.; Tornow, Werner; Wagner, Andreas

2017-09-01

We report photon-scattering experiments using bremsstrahlung at the γELBE facility of Helmholtz-Zentrum Dresden-Rossendorf and using quasi-monoenergetic, polarized γ beams at the HIγS facility of the Triangle Universities Nuclear Laboratory in Durham. To deduce the photoabsorption cross sections at high excitation energy and high level density, unresolved strength in the quasicontinuum of nuclear states has been taken into account. In the analysis of the spectra measured by using bremsstrahlung at γELBE, we perform simulations of statistical γ-ray cascades using the code γDEX to estimate intensities of inelastic transitions to low-lying excited states. Simulated average branching ratios are compared with model-independent branching ratios obtained from spectra measured by using monoenergetic γ beams at HIγS. E1 strength in the energy region of the pygmy dipole resonance is discussed in nuclei around mass 90 and in xenon isotopes. M1 strength in the region of the spin-flip resonance is also considered for xenon isotopes. The dipole strength function of 74Ge deduced from γELBE experiments is compared with the one obtained from experiments at the Oslo Cyclotron Laboratory. The low-energy upbend seen in the Oslo data is interpreted as M1 strength on the basis of shell-model calculations.

E1 and M1 strength functions at low energy

Directory of Open Access Journals (Sweden)

Schwengner Ronald

2017-01-01

Full Text Available We report photon-scattering experiments using bremsstrahlung at the γELBE facility of Helmholtz-Zentrum Dresden-Rossendorf and using quasi-monoenergetic, polarized γ beams at the HIγS facility of the Triangle Universities Nuclear Laboratory in Durham. To deduce the photoabsorption cross sections at high excitation energy and high level density, unresolved strength in the quasicontinuum of nuclear states has been taken into account. In the analysis of the spectra measured by using bremsstrahlung at γELBE, we perform simulations of statistical γ-ray cascades using the code γDEX to estimate intensities of inelastic transitions to low-lying excited states. Simulated average branching ratios are compared with model-independent branching ratios obtained from spectra measured by using monoenergetic γ beams at HIγS. E1 strength in the energy region of the pygmy dipole resonance is discussed in nuclei around mass 90 and in xenon isotopes. M1 strength in the region of the spin-flip resonance is also considered for xenon isotopes. The dipole strength function of 74Ge deduced from γELBE experiments is compared with the one obtained from experiments at the Oslo Cyclotron Laboratory. The low-energy upbend seen in the Oslo data is interpreted as M1 strength on the basis of shell-model calculations.

Study of crystal damage by ion implantation using micro RBS/channeling

International Nuclear Information System (INIS)

Grambole, D.; Herrmann, F.; Heera, V.; Meijer, J.

2007-01-01

The combination of microbeam implantation and in-situ micro RBS/channeling analysis in the Rossendorf nuclear microprobe facility enables crystal damage studies with high current densities not achievable in standard ion implantation experiments. Si(1 0 0) samples were implanted with 600 keV Si + ions and a fluence of 1 x 10 16 cm -2 . Using a beam spot of 200 μm x 200 μm current densities from 4 to 120 μA/cm 2 were obtained. The substrate temperature was varied between RT and 265 deg. C. The implanted regions were subsequently analysed by micro RBS/channeling with a 3 MeV He + beam having a spot size of 50 μm x 50 μm. Crystal damage up to amorphisation was observed in dependence on the substrate temperature. Above a critical temperature T C no amorphisation occurs. T C was determined for each series of samples implanted with the same ion current density j. It was found that the empirical Arrhenius relation j ∼ exp(-E a /kT C ), known from standard implantation experiments, is also valid at high current densities. The observed Arrhenius law can be derived from a model of epitaxial crystallisation stimulated by defect diffusion

Experimental and numerical investigation of the coolant mixing during fast deboration transients

International Nuclear Information System (INIS)

Hoehne, T.; Rohde, U.; Weiss, F.P.

1999-01-01

For the analysis of boron dilution transients and main steam line break scenarios the modeling of the coolant mixing inside the reactor vessel is important, because the reactivity insertion strongly depends on boron acid concentration or the coolant temperature distribution. Calculations for steady state flow conditions for the VVER-440 were performed with a CFD code (CFX-4). The comparison with experimental data and an analytical mixing model which is implemented in the neutron-kinetic code DYN3D showed a good agreement for near-nominal conditions. First experiments at the Rossendorf Mixing Test Facility ROCOM were performed simulating the start-up of the first main coolant pump. The reference reactor for the geometrically 1:5 scaled Plexiglas model is the German Konvoi type PWR. After demonstrating the capability of the CFD code to simulate these complicated flow transients, calculations were performed for the start-up of the first pump in a VVER-440 type reactor. These calculations are a first step of understanding the coolant mixing in the RPV of a VVER-440 type reactor under transient conditions. The results of the calculation show a very complex flow in the downcomer. A high downcomer of VVER-440 and the existence of the lower control rod chamber support coolant mixing is concluded. (author)

PREFACE: Fifteenth International Summer School on Vacuum, Electron and Ion Technologies (VEIT 2007)

Science.gov (United States)

Guerassimov, Nikolay; Möller, Wolfhard; Ghelev, Chavdar

2008-03-01

The International Summer School on Vacuum, Electron and Ion Technologies (VEIT) has been organized biannually since 1977. It is a forum for the interchange and dissemination of knowledge and ideas on the latest developments in electron-, ion-, and plasma-assisted technologies. The organizers of the event (since 2001) have been the Institute of Electronics, Bulgarian Academy of Sciences, Sofia, Bulgaria, the Institute of Ion Beam Physics and Materials Research, Forschungszentrum Dresden-Rossendorf, Dresden, Germany, and the Evrika Foundation, Sofia, Bulgaria. The fifteenth meeting of VEIT was held in the Black Sea resort of Sozopol, Bulgaria from 17-21 September 2007 and was attended by around 120 participants from 17 countries: Australia, Belgium, Bulgaria, Canada, Czech Republic, Germany, Hungary, Italy, The Netherlands, Poland, Pakistan, Romania, Sweden, Switzerland, Ukraine, UK and USA. Following the tradition of publishing the VEIT Proceedings, a selection of papers presented at the event is published in this volume of Journal of Physics: Conference Series, all peer reviewed to meet the originality and quality criteria of the journal. The school consisted of 11 oral and 3 poster sessions. There were 17 invited talks of general interest and 12 progress reports were presented orally. In total 86 contributed papers were presented during the three poster sessions. There were several scientific highlights covering the fundamentals of gas discharges and interaction of fast particles with solids, a wide range of conventional and novel applications such as for hard coatings and optical/protective layers, nanosized structures produced by evaporation, sputtering or external irradiation. Recent achievements in the modification of materials using charged particles or laser beams, thin layers deposition, properties, and characterization and novel materials, techniques, devices were highlighted. Despite the busy scientific program, the atmosphere was relaxed and informal

Department of Detectors and Nuclear Electronics: Overview

International Nuclear Information System (INIS)

Guzik, Z.

2004-01-01

Full text: The basic activities of the Department of Nuclear Electronics in 2003 were concentrated on following areas: - studies of new scintillation techniques, - contribution to the big European projects, - scientific contracts with European industry in respect to detection techniques - electronics for experiments in High Energy Physics, - development, investigation and production of silicon detectors - development of γ-ray spectrometry apparatus, - development of new generation State of the Art PCI based and USB based multi-channel analysers, - technical support for the Institute as the whole with special emphasis on networking, - normalisation activities. Most of the scientific achievements of the Department were summarized in 18 publications (released or in press). These papers were published mainly in IEEE Trans. on Nucl. Sci. and Nucl. Instr. and Methods. Besides that, our scientists presented 14 contributions at international conferences (such as IEEE Nuclear Science Symposium 2003 in Portland, USA or 3 th IEEE Real Time Conference in Montreal, Canada). Particularly, two papers were presented at IEEE NSS Conference in Portland presenting the first in-beam study of LSO/APD array detectors for PET in hadron therapy - this work was performed in the collaboration with FZR Rossendorf in Germany. Studies on new scintillation techniques were concentrated mainly on energy resolution investigations in scintillation detectors. The study of pure CsI and BGO at liquid nitrogen temperature showed some important observations concerning non-proportionality of the light yield versus energy of γ-quanta and intrinsic energy resolution of the scintillators. It suggested that a modification of scintillators by additional doping may improve their proportionality and in consequence, their energy resolution. The Department was involved in scientific collaborations with a number of international centers, such as CERN, the Royal Institute of Technology in Stockholm, FZR

Conditioning of spent fuel assemblies from the Rossendorf RFR research reactor in transport and storage containers of the type CASTOR MTR 2

International Nuclear Information System (INIS)

Schneider, B.; Hofmann, G.

1994-09-01

Most of the spent fuel assemblies are temporarily stored in the flooded fuel ponds AB 1 and AB 2 of the RFR, and some are still in the reactor core. The conditioning task described here is part of the RFR spent fuel management concept and covers the safe emplacement of the spent fuel elements in the CASTOR MTR 2 shipping containers and the sealing of the containers in compliance with the nuclear licence issued for the conditioning task. The transfer of the spent fuel assemblies from the present wet storage conditions to the dry storage conditions in the CASTOR MTR 2 containers is done by a mobile manipulation equipment consisting essentially of the transfer sluice gate and a transfer container. Subsequent to conditioning, the shipping containers are to be transported to a licensed intermediate storage facility to await their transport to a national radwaste repository. The technical handling tools for the transfer and manipulation are briefly described, as well as the process steps involved, putting emphasis on the detailed description of processes and the accompanying time frame, so that the conditioning task can be incorporated into the work plan of the entire project. The report further presents the EDP concept established for the task, including the required data archivation and documentation. (orig.) [de

The TOPFLOW multi-purpose thermohydraulic test facility

International Nuclear Information System (INIS)

Schaffrath, Andreas; Kruessenberg, A.-K.; Weiss, F.-P.; Prasser, H.-M.

2002-01-01

The TOPFLOW (Transient Two Phase Flow Test Facility) multi-purpose thermohydraulic test facility is being built for studies of steady-state and transient flow phenomena in two-phase flows, and for the development and validation of the models contained in CFD (Computational Fluid Dynamics) codes. The facility is under construction at the Institute for Safety Research of the Rossendorf Research Center (FZR). It will be operated together with the Dresden Technical University and the Zittau/Goerlitz School for Technology, Economics and Social Studies within the framework of the Nuclear Technology Competence Preservation Program. TOPFLOW, with its test sections and its flexible concept, is available as an attractive facility also to users from all European countries. Experiments are planned in these fields, among others: - Transient two-phase flows in vertical and horizontal pipes and pipes of any inclination as well as in geometries typical of nuclear reactors (annulus, hot leg). - Boiling in large vessels and water pools (measurements of steam generation, 3D steam content distribution, turbulence, temperature stratification). - Test of passive components and safety systems. - Condensation in horizontal pipes in the absence and presence of non-condensable gases. The construction phase of TOPFLOW has been completed more or less on schedule. Experiments can be started after a commissioning phase in the 3rd quarter of 2002. (orig.) [de

The SNEDAX Data Base, General Description and Users' Instructions

International Nuclear Information System (INIS)

Helm, F.

1996-09-01

The SNEDAX Data Base contains information on assemblies built and experiments performed in the fast neutron critical facilities SNEAK (FZK Karlsruhe), MASURCA (CEA Cadarache), ZEBRA (AEA Winfrith) and RRR (Rossendorf Ringzonenreaktor). This report describes the general scope of SNEDAX, the transfer of information from the experimental facilities, and the capabilities to produce graphics and input files for frequently used computer codes. The first part contains general information about the contents and the capabilities of the data base. The second part gives the instructions for persons who actually work with it. The contents in both parts is arranged in a similar way using as far as practical an analogous decimal coding of the sections. In the figures and the annex examples are given in the way in which the data are stored and how they are presented as graphics. The data base is described as it exists in the middle of 1996. It is recognized that there are still many improvements desirable, in particular with respect to a consistent description of the experiments, giving reasonable but not excessive amount of information. Since work in the field of fast critical experiments will be discontinued at FZK, it is planned that the further administration and improvement will be taken over by CEA Cadarache with the support of IPPE Obninsk

Quantitative AMS depth profiling of the hydrogen isotopes collected in graphite divertor and wall tiles of the tokamak ASDEX-Upgrade

International Nuclear Information System (INIS)

Sun, G.Y.; Friedrich, M.; Groetzschel, R.; Buerger, W.; Behrisch, R.; Garcia-Rosales, C.

1997-01-01

The accelerator mass spectrometry (AMS) facility at the 3 MV Tandetron in Rossendorf has been applied for quantitative depth profiling of deuterium and tritium in samples cut from graphite protection tiles at the vessel walls of the fusion experiment ASDEX-Upgrade at the Max-Planck-Institut fuer Plasmaphysik in Garching. The tritium originates from D(d,p)T fusion reactions in the plasma and it is implanted in the vessel walls together with deuterium atoms and ions from the plasma. The T concentrations in the surface layers down to the analyzing depth of about 25 μm are in the range of 10 11 to 5 x 10 15 T-atoms/cm 3 corresponding to a tritium retention of 3 x 10 10 to 3.5 x 10 12 T-atoms/cm 2 . The much higher deuterium concentrations in the samples were simultaneously measured by calibrated conventional SIMS. In the surface layers down to the analyzing depth of about 25 μm the deuterium concentrations are between 3 x 10 18 and 8 x 10 21 atoms/cm 3 , corresponding to a deuterium retention of 2.5 x 10 16 to 2.5 x 10 18 atoms/cm 2 The estimated total amount of tritium in the vessel walls is of the same order of magnitude as the total number of neutrons produced in D(d,n) 3 He reactions. (orig.)

Comparative assessment of condensation models for horizontal tubes

International Nuclear Information System (INIS)

Schaffrath, A.; Kruessenberg, A.K.; Lischke, W.; Gocht, U.; Fjodorow, A.

1999-01-01

The condensation in horizontal tubes plays an important role e.g. for the determination of the operation mode of horizontal steam generators of VVER reactors or passive safety systems for the next generation of nuclear power plants. Two different approaches (HOTKON and KONWAR) for modeling this process have been undertaken by Forschungszentrum Juelich (FZJ) and University for Applied Sciences Zittau/Goerlitz (HTWS) and implemented into the 1D-thermohydraulic code ATHLET, which is developed by the Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH for the analysis of anticipated and abnormal transients in light water reactors. Although the improvements of the condensation models are developed for different applications (VVER steam generators - emergency condenser of the SWR1000) with strongly different operation conditions (e.g. the temperature difference over the tube wall in HORUS is up to 30 K and in NOKO up to 250 K, the heat flux density in HORUS is up to 40 kW/m 2 and in NOKO up to 1 GW/m 2 ) both models are now compared and assessed by Forschungszentrum Rossendorf FZR e.V. Therefore, post test calculations of selected HORUS experiments were performed with ATHLET/KONWAR and compared to existing ATHLET and ATHLET/HOTKON calculations of HTWS. It can be seen that the calculations with the extension KONWAR as well as HOTKON improve significantly the agreement between computational and experimental data. (orig.) [de

Two-phase flow behaviour during a medium size cold leg LOCA test on PMK-2 (IAEA SPE-4)

International Nuclear Information System (INIS)

Szabados, L.; Prasser, H.M.; Schaefer, F.

1995-08-01

The experiment to the IAEA standard problem exercise No. 4 was carried out in April 1993 on the integral test facility PMK-2 in Budapest. It was a 3.2 mm break on the downcomer hed. The high pressure injection cooling was assumed to be not available. As an accident management measure bleed and feed on the secondary side of the steam generator was applied. Research Center Rossendorf contributed to the experiment of SPE-4 by supplying needle shaped conductivity probes for the measurement of local void fractions in the primary circuit of the PMK-II test facility. In the course of the standard problem exercise No. 4 RCR contributed with posttest calculations using the thermalhydraulic code ATHLET. The report comprises a description of the initial and boundary conditions of the test (chapter 3) and a phenomenological description of the thermalhydraulic events during the transient (chapter 4). The void fraction probe signals yields valuable information for deeper understanding of the thermalhydraulic occurrences and for code validation. This was the case particularly for correction of the level measurement. In chapter 5 a description of the thermalhydraulic occurrences from the viewpoint of code verification is given and the results of RELAP5 (KFKI-AEKI) and of ATHLET-calculations (RCR) are compared. Referring to this description, the sensitivity of the result to main influences is investigated using the ATHLET-code. (orig.) [de

Numerical simulations of counter-current two-phase flow experiments in a PWR hot leg model using an interfacial area density model

Energy Technology Data Exchange (ETDEWEB)

Hoehne, Thomas, E-mail: t.hoehne@hzdr.de [Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Safety Research, P.O. Box 510 119, D-01314 Dresden (Germany); Deendarlianto,; Lucas, Dirk [Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Safety Research, P.O. Box 510 119, D-01314 Dresden (Germany)

2011-10-15

In order to improve the understanding of counter-current two-phase flows and to validate new physical models, CFD simulations of 1/3rd scale model of the hot leg of a German Konvoi PWR with rectangular cross section was performed. Selected counter-current flow limitation (CCFL) experiments at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) were calculated with ANSYS CFX 12.1 using the multi-fluid Euler-Euler modeling approach. The transient calculations were carried out using a gas/liquid inhomogeneous multiphase flow model coupled with a k-{omega} turbulence model for each phase. In the simulation, the surface drag was approached by a new correlation inside the Algebraic Interfacial Area Density (AIAD) model. The AIAD model allows the detection of the morphological form of the two phase flow and the corresponding switching via a blending function of each correlation from one object pair to another. As a result this model can distinguish between bubbles, droplets and the free surface using the local liquid phase volume fraction value. A comparison with the high-speed video observations shows a good qualitative agreement. The results indicated that quantitative agreement of the CCFL characteristics between calculation and experimental data was obtained. The goal is to provide an easy usable AIAD framework for all Code users, with the possibility of the implementation of their own correlations.

Numerical simulations of counter-current two-phase flow experiments in a PWR hot leg model using an interfacial area density model

Energy Technology Data Exchange (ETDEWEB)

Hohne, T.; Deendarlianto; Vallee, C.; Lucas, D.; Beyer, M., E-mail: t.hoehne@hzdr.de [Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Inst. of Safety Research, Dresden (Germany)

2011-07-01

In order to improve the understanding of counter-current two-phase flows and to validate new physical models, CFD simulations of 1/3rd scale model of the hot leg of a German Konvoi PWR with rectangular cross section was performed. Selected counter-current flow limitation (CCFL) experiments at the Helmholtz-Zentrum Dresden- Rossendorf (HZDR) were calculated with ANSYS CFX 12.1 using the multi-fluid Euler-Euler modeling approach. The transient calculations were carried out using a gas/liquid inhomogeneous multiphase flow model coupled with a SST turbulence model for each phase. In the simulation, the surface drag was approached by a new correlation inside the Algebraic Interfacial Area Density (AIAD) model. The AIAD model allows the detection of the morphological form of the two phase flow and the corresponding switching via a blending function of each correlation from one object pair to another. As a result this model can distinguish between bubbles, droplets and the free surface using the local liquid phase volume fraction value. A comparison with the high-speed video observations shows a good qualitative agreement. The results indicated that quantitative agreement of the CCFL characteristics between calculation and experimental data was obtained. The goal is to provide an easy usable AIAD framework for all ANSYS CFX users, with the possibility of the implementation of their own correlations. (author)

Accident analysis for new reactor concepts and VVER type reactor design with advanced fuel. STC with Russia. Final report

International Nuclear Information System (INIS)

Grundmann, U.; Kliem, S.; Mittag, S.; Rohde, U.; Seidel, A.

2000-10-01

In the frame of a project on scientific-technical cooperation funded by BMBF/BMWi, the 3D reactor dynamics code DYN3D developed at Forschungszentrum Rossendorf (FZR), has been transferred to the Institute of Physics and Power Engineering (IPPE) Obninsk in Russia and integrated into the software package of IPPE. DYN3D has been coupled to a thermohydraulic system code used in IPPE making available 3D neutron kinetics within this software package. A new macroscopic cross section library has been created using a modified version of the WIMS/D4 code. This library includes data for modernized fuel design containing burnable absorbers in different concentrations, which is tested in VVER-1000 type reactors. The cross section library has been connected to DYN3D. Calculations were performed to check the library in comparison with other data libraries and codes. The code DYN3D and the coupled 3D neutron kinetics/thermal hydraulics code system were used to perform analyses of Anticipated Transients Without Scram (ATWS) for the reactor design ABV-67, an integral reactor concept with small power developed under participation of IPPE. The fluid dynamics code DINCOR developed at IPPE was transferred to FZR. It was used in validation calculations on test problems for the short-term core melt behaviour (CORVIS experiments). (orig.) [de

CFD and system analysis code investigations of the multidimensional flow mixing phenomena in the reactor pressure vessel

International Nuclear Information System (INIS)

Ceuca, S.C.; Herb, J.; Schoeffel, P.J.; Hollands, T.; Austregesilo, H.; Hristov, H.V.

2017-01-01

The realistic numerical prediction of transient fluid-dynamic scenarios including the complex, three-dimensional flow mixing phenomena occurring in the reactor pressure vessel (RPV) both in normal or abnormal operation are an important issue in today's reactor safety assessment studies. Both Computational Fluid Dynamics (CFD) tools as well as fluid-dynamic system analysis codes, each with its advantages and drawbacks, are commonly used to model such transients. Simulation results obtained with the open-source CFD tool-box OpenFOAM and the German thermal-hydraulic system code ATHLET (Analysis of THermal-hydraulics of LEaks and Transients), the later developed by Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) for the analysis of the whole spectrum of operational transients, design-basis accidents and beyond design basis accidents anticipated for nuclear energy facilities, are compared against experimental data from the ROssendorf Coolant Mixing (ROCOM) test facility. In the case of the OpenFOAM CFD simulations the influence of various turbulence models and numerical schemes has been assessed while in the case of the system analysis code ATHLET a multidimensional nodalization recommended for real power plant applications has been employed. The simulation results show a good agreement with the experimental data, indicating that both OpenFOAM and ATHLET can capture the key flow features of the mixing processes in the Reactor Pressure Vessel (RPV). (author)

Experimental investigation and CFD validation of Horizontal Air/Water slug flow

International Nuclear Information System (INIS)

Vallee, Christophe; Hoehne, Thomas

2007-01-01

For the investigation of co-current two-phase flows at atmospheric pressure and room temperature, the Horizontal Air/Water Channel (HAWAC) was built at Forschungszentrum Dresden-Rossendorf (FZD). At the channel inlet, a special device provides adjustable and well-defined inlet boundary conditions and therefore very good CFD validation possibilities. The HAWAC facility is designed for the application of optical measurement techniques, which deliver the high resolution required for CDF validation. Therefore, the 8 m long acrylic glass test-section with rectangular cross-section provides good observation possibilities. High-speed video observation was applied during slug flow. The camera images show the generation of slug flow from the inlet of the test-section. Parallel to the experiments, CFD calculations were carried out. The aim of the numerical simulations is to validate the prediction of slug flow with the existing multiphase flow models built in the commercial code ANSYS CFX. The Euler-Euler two-fluid model with the free surface option was applied to a grid of 600,000 control volumes. The turbulence was modelled separately for each phase using the k-ω based shear stress transport (SST) turbulence model. The results compare well in terms of slug formation, and breaking. The qualitative agreement between calculation and experiment is encouraging, while quantitative comparison show that further model improvement is needed. (author)

First test of the prompt gamma ray timing method with heterogeneous targets at a clinical proton therapy facility

International Nuclear Information System (INIS)

Hueso-González, Fernando; Enghardt, Wolfgang; Golnik, Christian; Petzoldt, Johannes; Pausch, Guntram; Fiedler, Fine; Priegnitz, Marlen; Römer, Katja E; Wagner, Andreas; Janssens, Guillaume; Prieels, Damien; Smeets, Julien; Vander Stappen, François

2015-01-01

Ion beam therapy promises enhanced tumour coverage compared to conventional radiotherapy, but particle range uncertainties significantly blunt the achievable precision. Experimental tools for range verification in real-time are not yet available in clinical routine. The prompt gamma ray timing method has been recently proposed as an alternative to collimated imaging systems. The detection times of prompt gamma rays encode essential information about the depth-dose profile thanks to the measurable transit time of ions through matter. In a collaboration between OncoRay, Helmholtz-Zentrum Dresden-Rossendorf and IBA, the first test at a clinical proton accelerator (Westdeutsches Protonentherapiezentrum Essen, Germany) with several detectors and phantoms is performed. The robustness of the method against background and stability of the beam bunch time profile is explored, and the bunch time spread is characterized for different proton energies. For a beam spot with a hundred million protons and a single detector, range differences of 5 mm in defined heterogeneous targets are identified by numerical comparison of the spectrum shape. For higher statistics, range shifts down to 2 mm are detectable. A proton bunch monitor, higher detector throughput and quantitative range retrieval are the upcoming steps towards a clinically applicable prototype. In conclusion, the experimental results highlight the prospects of this straightforward verification method at a clinical pencil beam and settle this novel approach as a promising alternative in the field of in vivo dosimetry. (paper)

In retrospect. 7th workshop RCA; Nachlese. 7. Workshop RCA. Conference report

Energy Technology Data Exchange (ETDEWEB)

Knappik, Reinhard [Verein fuer Kernverfahrenstechnik und Analytik Rossendorf e.V. (VKTA), Dresden-Rossendorf (Germany). Programmausschuss Workshop RCA

2013-08-15

The 7th Workshop RCA with 27 lectures and 12 poster presentation took place on 10 and 11 June 2013 in Dresden-Rossendorf. The traditional German event brought over 90 participants together from Germany, Austria, France, Switzerland and the Netherlands. This time the workshop put forward a special subject for the first time ('Obstacles and pitfalls when characterising waste packages'). A remarkable range of contributions was presented, which demonstrated the diversity and the problems of this subject matter. Medium to low radioactive waste and their final disposal was discussed. Other topics were the upcoming approval of recycling materials according to paragraph 29 StrlSchV as well as those from NORM (Naturally Occurring Radioactive Materials) regarding radionuclide analytics, the range of matrices to be processed and the practical problems this causes. Although the radiological feature was the central focus, other material aspects were dealt with, above all the approval of recycling materials when nuclear power plants are dismantled, but also in research institutes, which is demanding more and more attention. The lectures by Jessica Riemer (GSI Darmstadt) on the topic 'Waste material management of a research centre with heavy ion accelerators' and Elvira Mesalic (TU Munich) on 'Determining the activity inventory of bituminized old wastes' as well as the poster by Sina Brockmann on the 'Locally resolved analysis or uranium species using a couple systems of CLSM and LIFS' were awarded prizes for being outstanding presentations. (orig.)

Novel fluid dynamic instrumentation for mixing studies developed at ETH Zurich and PSI

International Nuclear Information System (INIS)

Prasser, H.-M.; Damsohn, M.; Frey, S.; Fokken, J.

2009-01-01

Wire-mesh sensors primarily developed for two-phase flows are known to be useful also for mixing studies in single-phase flows. A prominent example is the boron mixing test facility ROCOM in Rossendorf. ETH Zurich and PSI have started to use wire-mesh sensors for the characterization of the turbulent mixing process in T-junctions, which have gained a considerable relevance to nuclear safety since temperature fluctuations generated by the mixing of fluids of different temperature may cause dangerous thermal loads to the wall material. In the present paper, the application of a high-resolution wire-mesh sensor for the cross-section of the flow duct, combined with a novel wall sensor is reported. The wall sensor is as well based on a conductivity measurement, while the electrodes are manufactured as conducting structures directly flush to the surface of the channel wall. This type of nonintrusive sensor is able to provide information on concentration fluctuations from the boundary layer in experiments where salt tracers are used to substitute the temperature as transport scalar. In an experimental feasibility study it was furthermore shown that both wiremesh sensors and the new wall sensor are sensitive enough to record conductivity changes that are caused by temperature fluctuations in experiments without a tracer salt. This means that benefit can be taken from of high spatial and temporal resolution of both types of sensors to study temperature fluctuations. (author)

Comparison between wire mesh sensor and gamma densitometry void measurements in two-phase flows

Science.gov (United States)

Sharaf, S.; Da Silva, M.; Hampel, U.; Zippe, C.; Beyer, M.; Azzopardi, B.

2011-10-01

Wire mesh sensors (WMS) are fast imaging instruments that are used for gas-liquid and liquid-liquid two-phase flow measurements and experimental investigations. Experimental tests were conducted at Helmholtz-Zentrum Dresden-Rossendorf to test both the capacitance and conductance WMS against a gamma densitometer (GD). A small gas-liquid test facility was utilized. This consisted of a vertical round pipe approximately 1 m in length, and 50 mm internal diameter. A 16 × 16 WMS was used with high spatial and temporal resolutions. Air-deionized water was the two-phase mixture. The gas superficial velocity was varied between 0.05 m s-1 and 1.4 m s-1 at two liquid velocities of 0.2 and 0.7 m s-1. The GD consisted of a collimated source and a collimated detector. The GD was placed on a moving platform close to the plane of wires of the sensor, in order to align it accurately using a counter mechanism, with each of the wires of the WMS, and the platform could scan the full section of the pipe. The WMS was operated as a conductivity WMS for a half-plane with eight wires and as a capacitance WMS for the other half. For the cross-sectional void (time and space averaged), along each wire, there was good agreement between WMS and the GD chordal void fraction near the centre of the pipe.

Comparison between wire mesh sensor and gamma densitometry void measurements in two-phase flows

International Nuclear Information System (INIS)

Sharaf, S; Azzopardi, B; Da Silva, M; Hampel, U; Zippe, C; Beyer, M

2011-01-01

Wire mesh sensors (WMS) are fast imaging instruments that are used for gas–liquid and liquid–liquid two-phase flow measurements and experimental investigations. Experimental tests were conducted at Helmholtz-Zentrum Dresden-Rossendorf to test both the capacitance and conductance WMS against a gamma densitometer (GD). A small gas–liquid test facility was utilized. This consisted of a vertical round pipe approximately 1 m in length, and 50 mm internal diameter. A 16 × 16 WMS was used with high spatial and temporal resolutions. Air–deionized water was the two-phase mixture. The gas superficial velocity was varied between 0.05 m s −1 and 1.4 m s −1 at two liquid velocities of 0.2 and 0.7 m s −1 . The GD consisted of a collimated source and a collimated detector. The GD was placed on a moving platform close to the plane of wires of the sensor, in order to align it accurately using a counter mechanism, with each of the wires of the WMS, and the platform could scan the full section of the pipe. The WMS was operated as a conductivity WMS for a half-plane with eight wires and as a capacitance WMS for the other half. For the cross-sectional void (time and space averaged), along each wire, there was good agreement between WMS and the GD chordal void fraction near the centre of the pipe

In retrospect. 7th workshop RCA

International Nuclear Information System (INIS)

Knappik, Reinhard

2013-01-01

The 7th Workshop RCA with 27 lectures and 12 poster presentation took place on 10 and 11 June 2013 in Dresden-Rossendorf. The traditional German event brought over 90 participants together from Germany, Austria, France, Switzerland and the Netherlands. This time the workshop put forward a special subject for the first time ('Obstacles and pitfalls when characterising waste packages'). A remarkable range of contributions was presented, which demonstrated the diversity and the problems of this subject matter. Medium to low radioactive waste and their final disposal was discussed. Other topics were the upcoming approval of recycling materials according to paragraph 29 StrlSchV as well as those from NORM (Naturally Occurring Radioactive Materials) regarding radionuclide analytics, the range of matrices to be processed and the practical problems this causes. Although the radiological feature was the central focus, other material aspects were dealt with, above all the approval of recycling materials when nuclear power plants are dismantled, but also in research institutes, which is demanding more and more attention. The lectures by Jessica Riemer (GSI Darmstadt) on the topic 'Waste material management of a research centre with heavy ion accelerators' and Elvira Mesalic (TU Munich) on 'Determining the activity inventory of bituminized old wastes' as well as the poster by Sina Brockmann on the 'Locally resolved analysis or uranium species using a couple systems of CLSM and LIFS' were awarded prizes for being outstanding presentations. (orig.)

The training and research reactor of the Zittau Technical College

International Nuclear Information System (INIS)

Ackermann, G.; Hampel, R.; Konschak, K.

1979-01-01

The light-water moderated training and research reactor of the Zittau Technical College, which has been put into operation 1 July 1979, is described. Having a power of 10 MW, it is provided for education of students and advanced training of nuclear power plant staff members. High inherent nuclear safety and economy of operation are achieved by appropriate design of the reactor core and the use of fresh fuel elements provided for the 10-MW research reactor at the Rossendorf Central Institute for Nucleear Research for one year on a loan basis. Further characteristics of the reactor are easy accessibility of the core interior for in-core studies, sufficient external experimental channels, and a control and protection system meeting the requirements of teaching operation. The installed technological and dosimetric devices not only ensure reliable operation of the reactor, but also extend the potentialities of experimental work and education that is reported in detail. The principles on which the training programs are based are explained in the light of some examples. The training reactor is assumed to serve for providing basic knowledge about processes in nuclear power stations with pressurized water reactors. Where the behaviour of a nuclear power station cannot sufficiently be demonstrated by the training reactor, a reasonable completion of practical training at special simulation models and experimental facilities of the Technical College and at the nuclear power plant simulator of the Rheinsberg nuclear power plant school has been conceived. (author)

The NOKO/TOPFLOW facility for natural convection flow

International Nuclear Information System (INIS)

Hicken, E.F.; Jaegers, H.; Schaffrath, A.; Weiss, F.-P.

2002-01-01

For the study of the effectiveness of passive safety systems a high pressure (up to 7 MPa) and high power (up to 4 MW) test facility - named NOKO - has been constructed and operated at the Forschungszentrum Juelich. From 1996-1998 this facility was used for a project within the 4th FP of the EU 'European BWR R and D Cluster for Innovative Passive Safety Systems'. An overview and selected results are given for the tests with two bundles of the emergency condenser, with the building and plate condenser, with 4 different passive initiators, with a passive flooding system and with decay heat removal tests during shutdown. It has been decided to decrease substantially the safety research at the Forschungszentrum Juelich; to maintain the experimental competence for two-phase flow the NOKO facility will be transferred to the Forschungszentrum Rossendorf by the end of the year 2000 up to the beginning of the year 2001. The facility will be named TOPFLOW; the main objectives of future tests will be oriented towards more generic research: investigation of steady state and transient two-phase flow phenomena especially transient two-phase flow patterns, the development of two-phase flow instrumentation, the generation of a data basis for Computational Fluid Dynamic (CFD)-Code validation and testing of heat exchangers and safety systems. An overview will be given about the modifications and improvements related to the test facility and the planned tests. (author)

Department of Radiation Detectors: Overview

International Nuclear Information System (INIS)

Piekoszewski, J.

1998-01-01

design X-ray tube with ''needle-like anode'' for therapy of tumors began (KBN grant). In accomplishing the above, the Department cooperated with Polon IZOT and Dora Power Systems companies. Material modification using ion and plasma beams: The technology of modifying surfaces of industrially used materials by means of continuous and pulsed energy beams has been intensely studied for more than 20 years. In some fields it is presently utilized on a broad scale in industry. A significant role among various methods is played by continuous or pulsed ion and plasma beams. The P-IX Department jointly with the P-V Department utilizes some unique sources of intense ion-plasma pulses. Experiments on conventional implantation of ions into engineering components are carried out in cooperation with FZ Rossendorf, (Germany), and ITME (Warsaw). Pioneering of new applications of the pulsed ion beams is thus possible. The processing step in the experiments conducted in cooperation with FZR is carried out in our Institute. The main objectives of the Department in this field are: searching for new, original ways of modifying surface properties of solid materials by means of pulsed plasma beams, - implementation in the Institute and thus in the country of an ion implantation technique as a method of improving the quality of engineering tools. These objectives were accomplished in 1997 particularly by: - melting, and attempts of diffusive mixing, of selected metals with ceramic substrates by means of intense plasma pulses (proportion of ions of metal and of working gas varied in a controlled way) - construction of the source of nitrogen ions, - improving the useful properties of selected machine tools by means of conventional ion implantation, - working-out some diagnostics for pulsed plasma beams (power vs time measurement). In accomplishing the above the Department cooperated with the P-V Department, the Institute of Ion Beam Physics and Material Research (FZ Rossendorf, Germany), INCT

Wire-mesh sensors: an experimental tool for two-phase CDF model development and code validation

Energy Technology Data Exchange (ETDEWEB)

Prasser, H.M. [Forschungszentrum Rossendorf e.V., Dresden (Germany)

2004-07-01

Full text of publication follows:The Institute of Safety Research of the Forschungszentrum Rossendorf, Germany, has developed electrode-mesh sensors, which allow the measurement of the electrical conductivity distribution in a flow duct. This can be used either for the detection of the gaseous phase in a gas-liquid flow or for mixing studies in single phase flow, when the components have different electric conductivities. Two grids of crossing wires are placed into the flow closely behind each other. The wires of the first plane (transmitter plane) are supplied with pulses of a driving voltage in a successive order. The data acquisition is done by measuring the electrical currents arriving at the second grid (receiver wires). After the last transmitter electrode has been activated, a two-dimensional matrix is available that reflects the conductivities at crossing points of the electrodes of the two grids. Sequences of these 2D distributions are recorded with a rate of up to 10 kHz. Due to the high measuring rate each bubble is mapped in several successive instantaneous frames. This allows to obtain bubble size distributions as well as bubble-size resolved gas fraction profiles beside the visualisation and the calculation of profiles of the time-averaged void fraction. Two sensors placed behind each other can furthermore be used for bubble velocity measurements using cross-correlation techniques. Sensors with three layers of electrode grids can be used for the measurement of the velocity of individual bubbles. The sensor is widely used to study the evolution of the flow pattern in an upwards air-water flow. The experiments aim at closure equations describing forces acting on bubbles as well as coalescence and fragmentation frequencies for the implementation in CFD-codes. The largest sensor used until now has a circular measuring cross-section of about 200 mm diameter and is equipped with two grids of 64 wires. Therefore, the spatial resolution is 3 mm, the measuring

Wire-mesh sensors: an experimental tool for two-phase CDF model development and code validation

International Nuclear Information System (INIS)

Prasser, H.M.

2004-01-01

Full text of publication follows:The Institute of Safety Research of the Forschungszentrum Rossendorf, Germany, has developed electrode-mesh sensors, which allow the measurement of the electrical conductivity distribution in a flow duct. This can be used either for the detection of the gaseous phase in a gas-liquid flow or for mixing studies in single phase flow, when the components have different electric conductivities. Two grids of crossing wires are placed into the flow closely behind each other. The wires of the first plane (transmitter plane) are supplied with pulses of a driving voltage in a successive order. The data acquisition is done by measuring the electrical currents arriving at the second grid (receiver wires). After the last transmitter electrode has been activated, a two-dimensional matrix is available that reflects the conductivities at crossing points of the electrodes of the two grids. Sequences of these 2D distributions are recorded with a rate of up to 10 kHz. Due to the high measuring rate each bubble is mapped in several successive instantaneous frames. This allows to obtain bubble size distributions as well as bubble-size resolved gas fraction profiles beside the visualisation and the calculation of profiles of the time-averaged void fraction. Two sensors placed behind each other can furthermore be used for bubble velocity measurements using cross-correlation techniques. Sensors with three layers of electrode grids can be used for the measurement of the velocity of individual bubbles. The sensor is widely used to study the evolution of the flow pattern in an upwards air-water flow. The experiments aim at closure equations describing forces acting on bubbles as well as coalescence and fragmentation frequencies for the implementation in CFD-codes. The largest sensor used until now has a circular measuring cross-section of about 200 mm diameter and is equipped with two grids of 64 wires. Therefore, the spatial resolution is 3 mm, the measuring

Proceedings of the seventeenth Symposium of Atomic Energy Research, Vol. II

Energy Technology Data Exchange (ETDEWEB)

Vidovszky, Istvan [Kiadja az MTA KFKI Atomenergia Kutatointezet, H-1525 Budapest 114, P.O.Box 49 (Hungary)

2007-11-15

The present volume contains 83 papers, presented on the eleventh Symposium of Atomic Energy Research, held in Yalta, Ukraine, 23-29 September 2007. The papers are presented in their original form, i. e. no corrections or modifications were carried out. The content of this volume is divided into thematic groups: Fuel Management, Spectral and Core Calculations, Core Surveillance and Monitoring, CFD Analysis, Reactor Dynamics Thermal Hydraulics and Safety Analysis, Physical Problems of Spent Fuel Decommissioning and Radwaste, Actinide Transmutation and Spent Fuel Disposal, Core Operation, Experiments and Code Validation, History of TIC/AER - according to the presentation sequence on the Symposium (Author); Next corporations organizations: People's Deputy, Chairman of the Verkhovna Rada Subcommittee on Nuclear Policy and Nuclear Safety of Ukraine (Ukraine); Ministry for Fuel and Energy of Ukraine (Ukraine); Mintopenergo (Ukraine); Rosenergoatom (RU); Nuclear Safety Department of South-Ukraine NPP (Ukraine); State Nuclear Regulatory Committee of Ukraine (Ukraine); Energorisk, Ltd. (Ukraine); HmNPP (Ukraine); Khmelnitskaja NPP (Ukraine); Zaporizhzhya NPP, Energodar (Ukraine); Odessa National Polytechnic University, Odessa (Ukraine); NSC Kharkov Institute of Physics and Technology, Kharkov (Ukraine); Subsidiary 'Analytical Research Bureau for Nuclear Safety' (Ukraine); National nuclear power generating company 'Energoatom', Detached subdivision, Chornobyl NPP (Ukraine); JSC 'SNIIP-SYSTEMATOM' (RU); Moscow State Power-Engineering Institute, State University, Moscow (RU); Innovative company SNIIP Atom, LTD (RU); Budapest University of Technology and Economics, Institute of Nuclear Techniques, Budapest XI, Mueegyetem rkp. 9, 1111 (Hungary); Forschungszentrum Dresden- Rossendorf, Institute of Safety Research, P.O.B. 51 01 019, D-01314 Dresden (Germany)

Timing of Pulsed Prompt Gamma Rays for Background Discrimination

International Nuclear Information System (INIS)

Hueso-Gonzalez, F.; Golnik, C.; Berthel, M.; Dreyer, A.; Kormoll, T.; Rohling, H.; Pausch, G.; Enghardt, W.; Fiedler, F.; Heidel, K.; Schoene, S.; Schwengner, R.; Wagner, A.

2013-06-01

In the context of particle therapy, particle range verification is a major challenge for the quality assurance of the treatment. One approach is the measurement of the prompt gamma rays resulting from the tissue irradiation. A Compton camera based on several planes of position sensitive gamma ray detectors, together with an imaging algorithm, is expected to reconstruct the prompt gamma ray emission density profile, which is correlated with the dose distribution. At Helmholtz- Zentrum Dresden-Rossendorf (HZDR) and OncoRay, a camera prototype has been developed consisting of two scatter planes (CdZnTe cross strip detectors) and an absorber plane (Lu 2 SiO 5 block detector). The data acquisition is based on VME electronics and handled by software developed on the ROOT platform. The prototype was tested at the linear electron accelerator ELBE at HZDR, which was set up to produce bunched bremsstrahlung photons. Their spectrum has similarities with the one expected from prompt gamma rays in the clinical case, and these are also bunched with the accelerator frequency. The time correlation between the pulsed prompt photons and the measured signals was used for background discrimination, achieving a time resolution of 3 ns (2 ns) FWHM for the CZT (LSO) detector. A time-walk correction was applied for the LSO detector and improved its resolution to 1 ns. In conclusion, the detectors are suitable for time-resolved background discrimination in pulsed clinical particle accelerators. Ongoing tasks are the test of the imaging algorithms and the quantitative comparison with simulations. Further experiments will be performed at proton accelerators. (authors)

3. Workshop on measuring instruments for steady and transient multiphase flow; 3. Workshop: Messtechnik fuer stationaere und transiente Mehrphasenstroemungen

Energy Technology Data Exchange (ETDEWEB)

Prasser, H.M. [ed.

1999-12-01

The emphasis of the conference was on methods of measurement that show spatial distributions of phase fractions and velocity, particle sizes and bubbles of the disperse phase. Among the methods described were 3D X-ray tomography, grid sensor measurement of velocity profiles, and simultaneous measurement of bubble sizes and gas and liquid flow rates using an optical particle tracking method. Also presented were interesting developments in the field of local probes, e.g. an electrodiffusion probe. Another new development was the attempt to use optical tomography for investigations of two-phase flows. [German] Am 14. Oktober 1999 wurde in Rossendorf die dritte Veranstaltung in einer Serie von Workshops ueber Messtechnik fuer stationaere und transiente Mehrphasenstroemungen durchgefuehrt. Dieses Jahr koennen wir auf 11 interessante Vortraege zurueckblicken. Besonders hervorzuheben sind die beiden Hauptvortraege, die von Herrn Professor Hetsroni aus Haifa und Herrn Dr. Sengpiel aus Karlsruhe gehalten wurden. Ihnen und allen anderen Vortragenden moechten wir herzlich fuer ihren Beitrag zum Gelingen des Workshops danken. Erneut lag ein wichtiger Schwerpunkt auf Messverfahren, die raeumliche Verteilungen von Phasenanteilen und Geschwindigkeiten sowie die Groesse von Partikeln bzw. Blasen der dispersen Phase zugaenglich machen. So wurde ueber einen dreidimensional arbeitenden Roentgentomographen, ein Verfahren zur Messung von Geschwindigkeitsprofilen mit Gittersensoren und eine Methode zur simultanen Messung von Blasengroessen sowie Feldern von Gas- und Fluessigkeitsgeschwindigkeit mit einer optischen Partikelverfolgungstechnik vorgetragen. Daneben wurden interessante Entwicklungen auf dem Gebiet der lokalen Sonden vorgestellt, wie z.B. eine Elektrodiffusionssonde. Neue messtechnische Ansaetze waren ebenfalls vertreten; hervorzuheben ist der Versuch, die Methode der optischen Tomographie fuer die Untersuchung von Zweiphasenstroemungen nutzbar zu machen. (orig.)

German research reactor back-end provisions

International Nuclear Information System (INIS)

Koester, Siegfried; Gruber, Gerhard

2002-01-01

Germany has several types of Research Reactors in operation. These reactors use fuel containing uranium of U.S. origin. Basically all the fuel which will be spent until May 2006 will be returned to the U.S. under existing contracts with the U.S. Department of Energy. The contracts are based on the U.S. FRR SNF (Foreign Research Reactor Spent Nuclear Fuel) Program which started in May 1996 and which will last for 10 years. In 1990, the German Federal Government started a program to long-term store (approx. 40 years) and finally dispose of spent fuel in Germany after the so-called U.S. fuel return window will be closed. In order to long-term store the fuel, a special container was designed which covers all different types of spent fuel from the Research Reactors. The container called 'CASTOR MTR 2' is basically licensed and is already in use for the spent fuel of Russian origin from the 'Research Reactor Rossendorf' in the eastern part of Germany. All that fuel is expected to be stored in the existing intermediate storage facility, the so-called BZA (Brennelemente Zwischenlager Ahaus). BZA already accomodates spent fuel from the former THTR-300 high temperature reactor. A final repository does not yet exist in Germany. Alternative provisions to close the back-end of the Research Reactor fuel cycle are reprocessing at COGEMA (France) or in Russian facilities, perspectively. Waste return in a form to be agreed will be mandatory, at least in France. (author)

Infrared nanoscopy down to liquid helium temperatures

Science.gov (United States)

Lang, Denny; Döring, Jonathan; Nörenberg, Tobias; Butykai, Ádám; Kézsmárki, István; Schneider, Harald; Winnerl, Stephan; Helm, Manfred; Kehr, Susanne C.; Eng, Lukas M.

2018-03-01

We introduce a scattering-type scanning near-field infrared microscope (s-SNIM) for the local scale near-field sample analysis and spectroscopy from room temperature down to liquid helium (LHe) temperature. The extension of s-SNIM down to T = 5 K is in particular crucial for low-temperature phase transitions, e.g., for the examination of superconductors, as well as low energy excitations. The low temperature (LT) s-SNIM performance is tested with CO2-IR excitation at T = 7 K using a bare Au reference and a structured Si/SiO2-sample. Furthermore, we quantify the impact of local laser heating under the s-SNIM tip apex by monitoring the light-induced ferroelectric-to-paraelectric phase transition of the skyrmion-hosting multiferroic material GaV4S8 at Tc = 42 K. We apply LT s-SNIM to study the spectral response of GaV4S8 and its lateral domain structure in the ferroelectric phase by the mid-IR to THz free-electron laser-light source FELBE at the Helmholtz-Zentrum Dresden-Rossendorf, Germany. Notably, our s-SNIM is based on a non-contact atomic force microscope (AFM) and thus can be complemented in situ by various other AFM techniques, such as topography profiling, piezo-response force microscopy (PFM), and/or Kelvin-probe force microscopy (KPFM). The combination of these methods supports the comprehensive study of the mutual interplay in the topographic, electronic, and optical properties of surfaces from room temperature down to 5 K.

Nitrogen injection in stagnant liquid metal. Eulerian-Eulerian and VOF calculations by fluent

International Nuclear Information System (INIS)

Pena, A.; Esteban, G.A.

2004-01-01

High power spallation sources are devices that can be very useful in different fields, as medicine, material science, and also in the Accelerator Driven Systems (ADS). This devices use Heavy Liquid Metals (HLM) as the spallation target. Furthermore, HLM are thought to be the coolant of those big energy sources produced by the process. Fast breeder reactors, advanced nuclear reactors, as well as the future designs of fusion reactors, also consider HLM as targets or coolants. Gas injection in liquid metal flows allows the enhancement of this coolant circulation. The difference in densities between the gas and the liquid metal is a big challenge for the multiphase models implemented in the Computational Fluid Dynamics (CFD) codes. Also the changing shape of the bubbles involves extra difficulties in the calculations. A N 2 flow in stagnant Lead-Bismuth eutectic (Pb-Bi), experiment available at Forschungszentrum Rossendorf e.V (FZR) in Germany, was used in one of the work-packages of the ASCHLIM project (EU contract number FIKW-CT-2001-80121). In this paper, calculations made by the UPV/EHU (University of the Basque Country) show measuring data compared with numerical results using the CFD (Computational Fluid Dynamics) code FLUENT and two multiphase models: the Eulerian-Eulerian and the Volume of Fluid (VOF). The interpretation of the experimental resulting velocities was difficult, because some parameters were not known, bubble trajectory and bubble shape, for example, as direct optical methods cannot be used, like it is done with water experiments. (author)

Application of large-eddy simulation to pressurized thermal shock: Assessment of the accuracy

International Nuclear Information System (INIS)

Loginov, M.S.; Komen, E.M.J.; Hoehne, T.

2011-01-01

Highlights: → We compare large-eddy simulation with experiment on the single-phase pressurized thermal shock problem. → Three test cases are considered, they cover entire range of mixing patterns. → The accuracy of the flow mixing in the reactor pressure vessel is assessed qualitatively and quantitatively. - Abstract: Pressurized Thermal Shock (PTS) is identified as one of the safety issues where Computational Fluid Dynamics (CFD) can bring real benefits. The turbulence modeling may impact overall accuracy of the calculated thermal loads on the vessel walls, therefore advanced methods for turbulent flows are required. The feasibility and mesh resolution of LES for single-phase PTS are assessed earlier in a companion paper. The current investigation deals with the accuracy of LES approach with respect to the experiment. Experimental data from the Rossendorf Coolant Mixing (ROCOM) facility is used as a basis for validation. Three test cases with different flow rates are considered. They correspond to a buoyancy-driven, a momentum-driven, and a transitional coolant mixing pattern in the downcomer. Time- and frequency-domain analysis are employed for comparison of the numerical and experimental data. The investigation shows a good qualitative prediction of the bulk flow patterns. The fluctuations are modeled correctly. A conservative estimate of the temperature drop near the wall can be obtained from the numerical results with safety factor of 1.1-1.3. In general, the current LES gives a realistic and reliable description of the considered coolant mixing experiments. The accuracy of the prediction is definitely improved with respect to earlier CFD simulations.

Optimization aspects of the new nELBE photo-neutron source

Directory of Open Access Journals (Sweden)

Schwengner R.

2010-10-01

Full Text Available The nELBE beamline at Forschungszentrum Dresden-Rossendorf (FZD provides intense neutron beams by stopping primary electrons in a liquid lead target, where neutrons are produced by bremsstrahlung photons via (γ,n reactions. With the aim to increase the neutron yield through the enhancement of the electron beam energy (from the current 40 MeV limit up to 50 MeV, as well as to minimize several sources of background that are presently affecting the measurements, a new neutron beam-line and a new, larger neutron experimental room have been designed. The optimization of the neutron/photon ratio, the minimization of the backscattered radiation from the walls and the possibility to have better experimental conditions are the main advantages of the new design. To optimize the beamline, extensive simulations with the particle interaction and transport code FLUKA have been performed. Starting from the primary electron beam, both the photon and neutron radiation fields have been fully characterized. To have a cross-check of the results, the calculated values of the neutron yields at different energies of the primary beam have been compared both with an independent simulation with the MCNP code and with analytical calculations, obtaining a very satisfactory agreement at the level of few percent. The evaluated radiation fields have been used to optimize the direction of the new neutron beamline, in order to minimize the photon flash contribution. A general overview of the new photo-neutron source, together with all the steps of the optimization study, is here presented and discussed.

Annual report 2015. Institute of Resource Ecology

International Nuclear Information System (INIS)

Stumpf, Thorsten

2016-01-01

The Institute of Resource Ecology (IRE) is one of the eight institutes of the Helmholtz- Zentrum Dresden-Rossendorf (HZDR). The research activities are mainly integrated into the program ''Nuclear Waste Management, Safety and Radiation Research (NUSAFE)'' of the Helmholtz Association (HGF) and focused on the topics ''Safety of Nuclear Waste Disposal'' and ''Safety Research for Nuclear Reactors''. Additionally, various activities have been started investigating chemical and environmental aspects of processing and recycling of strategic metals, namely rare earth elements. These activities are located in the HGF program ''Energy Efficiency, Materials and Resources (EMR)''. Thus, all scientific work of the IRE belongs to the research field ''Energy'' of the HGF. The research objective is the protection of humans and the environment from hazards caused by pollutants resulting from technical processes that produce energy and raw materials. Treating technology and ecology as a unity is the major scientific challenge in assuring the safety of technical processes and gaining their public acceptance. We investigate the ecological risks ensued by radioactive and non-radioactive metals in the context of nuclear waste disposal, the production of energy in nuclear power plants and in processes along the value chain of metalliferous raw materials. A common goal is to generate better understanding about the dominating processes essential for metal mobilization and immobilization on the molecular level by using advanced spectroscopic methods. This in turn enables us to assess the macroscopic phenomena, including models, codes and data for predictive calculations, which determine the transport and distribution of contaminants in the environment.

Annual report 2016. Institute of Resource Ecology

International Nuclear Information System (INIS)

Stumpf, Thorsten; Foerstendorf, Harald; Bok, Frank; Richter, Anke

2017-01-01

The Institute of Resource Ecology (IRE) is one of the eight institutes of the Helmholtz-Zentrum Dresden - Rossendorf (HZDR). The research activities are mainly integrated into the program ''Nuclear Waste Management, Safety and Radiation Research (NUSAFE)'' of the Helmholtz Association (HGF) and focused on the topics ''Safety of Nuclear Waste Disposal'' and ''Safety Research for Nuclear Reactors''. Additionally, various activities have been started investigating chemical and environmental aspects of processing and recycling of strategic metals, namely rare earth elements. These activities are located in the HGF program ''Energy Efficiency, Materials and Resources (EMR)''. Both programs, and therefore all work which is done at IRE, belong to the research sector ''Energy'' of the HGF. The research objectives are the protection of humans and the environment from hazards caused by pollutants resulting from technical processes that produce energy and raw materials. Treating technology and ecology as a unity is the major scientific challenge in assuring the safety of technical processes and gaining their public acceptance. We investigate the ecological risks exerted by radioactive and non-radioactive metals in the context of nuclear waste disposal, the production of energy in nuclear power plants and in processes along the value chain of metalliferous raw materials. A common goal is to generate better understanding about the dominating processes essential for metal mobilization and immobilization on the molecular level by using advanced spectroscopic methods. This in turn enables us to assess the macroscopic phenomena, including models, codes and data for predictive calculations, which determine the transport and distribution of contaminants in the environment.

Annual report 2014. Institute of Resource Ecology

Energy Technology Data Exchange (ETDEWEB)

Stumpf, Thorsten (ed.)

2015-07-01

The Institute of Resource Ecology (IRE) is one of the eight institutes of the Helmholtz-Zentrum Dresden - Rossendorf (HZDR). The research activities are mainly integrated into the program ''Nuclear Waste Management, Safety and Radiation Research (NUSAFE)'' of the Helmholtz Association (HGF) and focused on the topics ''Safety of Nuclear Waste Disposal'' and ''Safety Research for Nuclear Reactors''. Additionally, various activities have been started investigating chemical and environmental aspects of processing and recycling of strategic metals, namely rare earth elements. These activities are located in the HGF program ''Energy Efficiency, Materials and Resources (EMR)''. Both programs, and therefore all work which is done at IRE, belong to the research sector ''Energy'' of the HGF. The research objectives are the protection of humans and the environment from hazards caused by pollutants resulting from technical processes that produce energy and raw materials. Treating technology and ecology as a unity is the major scientific challenge in assuring the safety of technical processes and gaining their public acceptance. We investigate the ecological risks exerted by radioactive and nonradioactive metals in the context of nuclear waste disposal, the production of energy in nuclear power plants, and in processes along the value chain of metalliferous raw materials. A common goal is to generate better understanding about the dominating processes essential for metal mobilization and immobilization on the molecular level by using advanced spectroscopic methods. This in turn enables us to assess the macroscopic phenomena, including models, codes, and data for predictive calculations, which determine the transport and distribution of contaminants in the environment.

Annual report 2015. Institute of Resource Ecology

Energy Technology Data Exchange (ETDEWEB)

Stumpf, Thorsten (ed.)

2016-07-01

The Institute of Resource Ecology (IRE) is one of the eight institutes of the Helmholtz- Zentrum Dresden-Rossendorf (HZDR). The research activities are mainly integrated into the program ''Nuclear Waste Management, Safety and Radiation Research (NUSAFE)'' of the Helmholtz Association (HGF) and focused on the topics ''Safety of Nuclear Waste Disposal'' and ''Safety Research for Nuclear Reactors''. Additionally, various activities have been started investigating chemical and environmental aspects of processing and recycling of strategic metals, namely rare earth elements. These activities are located in the HGF program ''Energy Efficiency, Materials and Resources (EMR)''. Thus, all scientific work of the IRE belongs to the research field ''Energy'' of the HGF. The research objective is the protection of humans and the environment from hazards caused by pollutants resulting from technical processes that produce energy and raw materials. Treating technology and ecology as a unity is the major scientific challenge in assuring the safety of technical processes and gaining their public acceptance. We investigate the ecological risks ensued by radioactive and non-radioactive metals in the context of nuclear waste disposal, the production of energy in nuclear power plants and in processes along the value chain of metalliferous raw materials. A common goal is to generate better understanding about the dominating processes essential for metal mobilization and immobilization on the molecular level by using advanced spectroscopic methods. This in turn enables us to assess the macroscopic phenomena, including models, codes and data for predictive calculations, which determine the transport and distribution of contaminants in the environment.

Annual report 2016. Institute of Resource Ecology

Energy Technology Data Exchange (ETDEWEB)

Stumpf, Thorsten [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Inst. of Resource Ecology; Foerstendorf, Harald; Bok, Frank; Richter, Anke (eds.) [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Surface Processes

2017-06-01

The Institute of Resource Ecology (IRE) is one of the eight institutes of the Helmholtz-Zentrum Dresden - Rossendorf (HZDR). The research activities are mainly integrated into the program ''Nuclear Waste Management, Safety and Radiation Research (NUSAFE)'' of the Helmholtz Association (HGF) and focused on the topics ''Safety of Nuclear Waste Disposal'' and ''Safety Research for Nuclear Reactors''. Additionally, various activities have been started investigating chemical and environmental aspects of processing and recycling of strategic metals, namely rare earth elements. These activities are located in the HGF program ''Energy Efficiency, Materials and Resources (EMR)''. Both programs, and therefore all work which is done at IRE, belong to the research sector ''Energy'' of the HGF. The research objectives are the protection of humans and the environment from hazards caused by pollutants resulting from technical processes that produce energy and raw materials. Treating technology and ecology as a unity is the major scientific challenge in assuring the safety of technical processes and gaining their public acceptance. We investigate the ecological risks exerted by radioactive and non-radioactive metals in the context of nuclear waste disposal, the production of energy in nuclear power plants and in processes along the value chain of metalliferous raw materials. A common goal is to generate better understanding about the dominating processes essential for metal mobilization and immobilization on the molecular level by using advanced spectroscopic methods. This in turn enables us to assess the macroscopic phenomena, including models, codes and data for predictive calculations, which determine the transport and distribution of contaminants in the environment.

German concept and status of the disposal of spent fuel elements from German research reactors

International Nuclear Information System (INIS)

Komorowski, K.; Storch, S.; Thamm, G.

1995-01-01

Eight research reactors with a power ≥ 100 kW are currently being operated in the Federal Republic of Germany. These comprise three TRIGA-type reactors (power 100 kW to 250 kW), four swimming-pool reactors (power 1 MW to 10 MW) and one DIDO type reactor (power 23 MW). The German research reactors are used for neutron scattering for basic research in the field of solid state research, neutron metrology, for the fabrication of isotopes and for neutron activation analysis for medicine and biology, for investigating the influence of radiation on materials and for nuclear fuel behavior. It will be vital to continue current investigations in the future. Further operation of the German research reactors is therefore indispensable. Safe, regular disposal of the irradiated fuel elements arising now and in future operation is of primary importance. Furthermore, there are several plants with considerable quantities of spent fuel, the safe disposal of which is a matter of urgency. These include above all the VKTA facilities in Rossendorf and also the TRIGA reactors, where disposal will only be necessary upon decommissioning. The present paper report is concerned with the disposal of fuel from the German research reactors. It briefly deals with the situation in the USA since the end of 1988, describes interim solutions for current disposal requirements and then mainly concentrates on the German disposal concept currently being prepared. This concept initially envisages the long-term (25--50 years) dry interim storage of fuel elements in special containers in a central German interim store with subsequent direct final disposal without reprocessing of the irradiated fuel

Annual report 2014. Institute of Resource Ecology

International Nuclear Information System (INIS)

Stumpf, Thorsten

2015-01-01

The Institute of Resource Ecology (IRE) is one of the eight institutes of the Helmholtz-Zentrum Dresden - Rossendorf (HZDR). The research activities are mainly integrated into the program ''Nuclear Waste Management, Safety and Radiation Research (NUSAFE)'' of the Helmholtz Association (HGF) and focused on the topics ''Safety of Nuclear Waste Disposal'' and ''Safety Research for Nuclear Reactors''. Additionally, various activities have been started investigating chemical and environmental aspects of processing and recycling of strategic metals, namely rare earth elements. These activities are located in the HGF program ''Energy Efficiency, Materials and Resources (EMR)''. Both programs, and therefore all work which is done at IRE, belong to the research sector ''Energy'' of the HGF. The research objectives are the protection of humans and the environment from hazards caused by pollutants resulting from technical processes that produce energy and raw materials. Treating technology and ecology as a unity is the major scientific challenge in assuring the safety of technical processes and gaining their public acceptance. We investigate the ecological risks exerted by radioactive and nonradioactive metals in the context of nuclear waste disposal, the production of energy in nuclear power plants, and in processes along the value chain of metalliferous raw materials. A common goal is to generate better understanding about the dominating processes essential for metal mobilization and immobilization on the molecular level by using advanced spectroscopic methods. This in turn enables us to assess the macroscopic phenomena, including models, codes, and data for predictive calculations, which determine the transport and distribution of contaminants in the environment.

Annual report 2013. Institute of Resource Ecology

International Nuclear Information System (INIS)

Stumpf, Thorsten

2013-01-01

The Institute of Resource Ecology (IRE) is one of the eight institutes of the Helmholtz-Zentrum Dresden-Rossendorf (HZDR). The Research activities are mainly integrated into the program ''Nuclear Safety Research (NUSAFE)'' of the Helmholtz Association (HGF) and focused on the topics ''Safety of Nuclear Waste Disposal'' and ''Safety Research for Nuclear Reactors''. Additionally, various activities have been started investigating chemical and environmental aspects of processing and recycling of strategic metals, namely rare earth elements. These activities are located in the HGF program ''Energy Efficiency, Materials and Resources (EMR)''. Both programs, and therefore all work which is done at IRE, belong to the research sector ''Energy'' of the HGF. The research objectives are the protection of humans and the environment from hazards caused by pollutants resulting from technical processes that produce energy and raw materials. Treating technology and ecology as a unity is the major scientific challenge in assuring the safety of technical processes and gaining their public acceptance. Namely, we investigate the ecological risks exerted by radioactive and non-radioactive metals in the context of nuclear waste disposal, the production of energy in nuclear power plants and in processes along the value chain of metalliferous raw materials. A common goal is to generate better understanding about the dominating processes essential for metal mobilization and immobilization on the molecular level. This in turn enables us to assess the macroscopic phenomena, including models, codes and data for predictive calculations, which determine the transport and distribution of contaminants in the environment.

Two-phase flow pattern measurements with a wire mesh sensor in a direct steam generating solar thermal collector

Science.gov (United States)

Berger, Michael; Mokhtar, Marwan; Zahler, Christian; Willert, Daniel; Neuhäuser, Anton; Schleicher, Eckhard

2017-06-01

At Industrial Solar's test facility in Freiburg (Germany), two phase flow patterns have been measured by using a wire mesh sensor from Helmholtz Zentrum Dresden-Rossendorf (HZDR). Main purpose of the measurements was to compare observed two-phase flow patterns with expected flow patterns from models. The two-phase flow pattern is important for the design of direct steam generating solar collectors. Vibrations should be avoided in the peripheral piping, and local dry-outs or large circumferential temperature gradients should be prevented in the absorber tubes. Therefore, the choice of design for operation conditions like mass flow and steam quality are an important step in the engineering process of such a project. Results of a measurement with the wire mesh sensor are the flow pattern and the plug or slug frequency at the given operating conditions. Under the assumption of the collector power, which can be assumed from previous measurements at the same collector and adaption with sun position and incidence angle modifier, also the slip can be evaluated for a wire mesh sensor measurement. Measurements have been performed at different mass flows and pressure levels. Transient behavior has been tested for flashing, change of mass flow, and sudden changes of irradiation (cloud simulation). This paper describes the measurements and the method of evaluation. Results are shown as extruded profiles in top view and in side view. Measurement and model are compared. The tests have been performed at low steam quality, because of the limits of the test facility. Conclusions and implications for possible future measurements at larger collectors are also presented in this paper.

Fast digitizing and digital signal processing of detector signals

International Nuclear Information System (INIS)

Hannaske, Roland

2008-01-01

A fast-digitizer data acquisition system recently installed at the neutron time-of-flight experiment nELBE, which is located at the superconducting electron accelerator ELBE of Forschungszentrum Dresden-Rossendorf, is tested with two different detector types. Preamplifier signals from a high-purity germanium detector are digitized, stored and finally processed. For a precise determination of the energy of the detected radiation, the moving-window deconvolution algorithm is used to compensate the ballistic deficit and different shaping algorithms are applied. The energy resolution is determined in an experiment with γ-rays from a 22 Na source and is compared to the energy resolution achieved with analogously processed signals. On the other hand, signals from the photomultipliers of barium fluoride and plastic scintillation detectors are digitized. These signals have risetimes of a few nanoseconds only. The moment of interaction of the radiation with the detector is determined by methods of digital signal processing. Therefore, different timing algorithms are implemented and tested with data from an experiment at nELBE. The time resolutions achieved with these algorithms are compared to each other as well as to reference values coming from analog signal processing. In addition to these experiments, some properties of the digitizing hardware are measured and a program for the analysis of stored, digitized data is developed. The analysis of the signals shows that the energy resolution achieved with the 10-bit digitizer system used here is not competitive to a 14-bit peak-sensing ADC, although the ballistic deficit can be fully corrected. However, digital methods give better result in sub-ns timing than analog signal processing. (orig.)

Numerical Simulations of Counter Current Flow Experiments Using a Morphology Detection Algorithm

Directory of Open Access Journals (Sweden)

Thomas Höhne

2012-09-01

Full Text Available In order to improve the understanding of counter-current two-phase flows and to validate new physical models, CFD simulations of 1/3rd scale model of the hot leg of a German Konvoi PWR with rectangular cross section was performed. Selected counter-current flow limitation (CCFL experiments at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR were calculated with ANSYS CFX 12.1 using the multi-fluid Euler-Euler modeling approach. The transient calculations were carried out using a gas/liquid inhomogeneous multiphase flow model coupled with a SST turbulence model for each phase. In the simulation, the surface drag was approached by a new correlation inside the Algebraic Interfacial Area Density (AIAD model. The AIAD model allows the detection of the morphological form of the two phase flow and the corresponding switching via a blending function of each correlation from one object pair to another. As a result this model can distinguish between bubbles, droplets and the free surface using the local liquid phase volume fraction value. A comparison with the high-speed video observations shows a good qualitative agreement. The results indicated that quantitative agreement of the CCFL characteristics between calculation and experimental data was obtained. To validate the model and to study scaling effects CFD simulations of the CCFL phenomenon in a full scale PWR hot leg of the UPTF test facility were performed. Also these results indicated a good agreement between the calculation and experimental data. The final goal is to provide an easy usable AIAD framework for all ANSYS CFX users, with the possibility of the implementation of their own correlations.

Coolant mixing in pressurized water reactors. Pt. 1. Feasibility of closed analytical solutions and simulation of the mixing with CFX-4. Final report

International Nuclear Information System (INIS)

Grunwald, G.; Hoehne, T.; Prasser, H.M.; Rohde, U.

2001-10-01

The project was aimed at the analytical and numerical simulation of coolant mixing in the downcomer and the lower plenum of PWRs. Generally, the coolant mixing is of relevance for two classes of accident scenarios - boron dilution and cold water transients. For the investigation of the relevant mixing phenomena, the Rossendorf test facility ROCOM has been designed. ROCOM is a 1:5 scaled Plexiglas trademark model of the PWR Konvoi allowing velocity measurements by the LDA technique. Design and construction of the ROCOM facility including the measurement equipment were performed in a second part of the project. For the design of the facility, CFD calculations were performed to analyze the scaling of the model. It was found, that the scaling of 1:5 to the prototype meets both: physical and economical demands. A theoretical 2D-model of the downcomer flow was developed based on the potential theory. The coolant inlet is represented by mass sources. Potential vortices were superposed to describe large scale recirculations. However, the method requires an a-priory knowledge of the location and intensity of the vorticity sources. Therefore, the main goal of the project was the numerical simulation of the coolant mixing of different PWRs. The temperature and boron concentration fields established by the coolant mixing during nominal and transient flow conditions in the pressure vessel of the PWR Konvoi and the Russian type WWER-440 were investigated. The calculations were carried out with the CFD-code CFX 4. The results of the CFD calculation are found in the final report. The report is based on the Ph.D. work of T. Hoehne. (orig.) [de

Annual report 2013. Institute of Resource Ecology

Energy Technology Data Exchange (ETDEWEB)

Stumpf, Thorsten (ed.)

2013-07-01

The Institute of Resource Ecology (IRE) is one of the eight institutes of the Helmholtz-Zentrum Dresden-Rossendorf (HZDR). The Research activities are mainly integrated into the program ''Nuclear Safety Research (NUSAFE)'' of the Helmholtz Association (HGF) and focused on the topics ''Safety of Nuclear Waste Disposal'' and ''Safety Research for Nuclear Reactors''. Additionally, various activities have been started investigating chemical and environmental aspects of processing and recycling of strategic metals, namely rare earth elements. These activities are located in the HGF program ''Energy Efficiency, Materials and Resources (EMR)''. Both programs, and therefore all work which is done at IRE, belong to the research sector ''Energy'' of the HGF. The research objectives are the protection of humans and the environment from hazards caused by pollutants resulting from technical processes that produce energy and raw materials. Treating technology and ecology as a unity is the major scientific challenge in assuring the safety of technical processes and gaining their public acceptance. Namely, we investigate the ecological risks exerted by radioactive and non-radioactive metals in the context of nuclear waste disposal, the production of energy in nuclear power plants and in processes along the value chain of metalliferous raw materials. A common goal is to generate better understanding about the dominating processes essential for metal mobilization and immobilization on the molecular level. This in turn enables us to assess the macroscopic phenomena, including models, codes and data for predictive calculations, which determine the transport and distribution of contaminants in the environment.

Iodination of the humic samples from HUPA project

International Nuclear Information System (INIS)

Reiller, P.; Mercier-Bion, F.; Barre, N.; Gimenez, N.; Miserque, F.

2005-01-01

The interaction of iodine with natural organic matter in general and with humic substances (HS) in particular, has been the subject of numerous studies. It has come to a consensus that in soils as well as in aquatic systems, the speciation of iodine is closely related to the redox potential of the medium. In oxidizing media, as in sea water or upper horizons, the major part of iodine is found in iodate form IO 3 - , whereas in reducing media, iodide I - is the major specie. Nevertheless, it has been shown that in some cases, organically bound iodine can dominate the speciation either as methyl iodide or bounded to humic substances. It is now also clear that this reactivity is closely related to the occurrence of molecular iodine I 2 (aq) and its disproportionation to HIO and I - . The reaction scheme can be viewed as an electrophilic substitution of an hydrogen to an iodine atom on a phenolic ring. This scheme has been validated in the case of HS on different samples including HUPA, and the covalent character of this interaction has been shown using electrospray ionization mass spectroscopy (ESI-MS), X-ray photoelectron spectroscopy. Nevertheless, in some of the latter studies, the characterization of the final reaction products did not satisfy the authors completely as total separation from I - could not be achieved. Thus, further studies were led using HUPA samples: natural humic and fulvic extract from Gorleben and synthetic samples obtained form FZ Rossendorf. Dialysis procedures were envisaged to improve the incomplete separation between the colloidal humic matter and the iodide ions either unreacted or produced by the reaction. (orig.)

Elastic recoil atomic spectroscopy of light elements with sub-nanometer depth resolution; Elastische Rueckstossatomspektrometrie leichter Elemente mit Subnanometer-Tiefenaufloesung

Energy Technology Data Exchange (ETDEWEB)

Kosmata, Marcel

2011-06-30

In this thesis the QQDS magnetic spectrometer that is used for high resolution ion beam analysis (IBA) of light elements at the Helmholtz-Zentrum Dresden-Rossendorf is presented for the first time. In addition all parameters are investigated that influence the analysis. Methods and models are presented with which the effects can be minimised or calculated. There are five focal points of this thesis. The first point is the construction and commissioning of the QQDS magnetic spectrometer, the corresponding scattering chamber with all the peripherals and the detector, which is specially developed for high resolution elastic recoil detection. Both the reconstructed spectrometer and the detector were adapted to the specific experimental conditions needed for high-resolution Ion beam analysis of light elements and tested for routine practice. The detector consists of two components. At the back end of the detector a Bragg ionization chamber is mounted, which is used for the particle identification. At the front end, directly behind the entrance window a proportional counter is mounted. This proportional counter includes a highresistance anode. Thus, the position of the particles is determined in the detector. The following two points concern fundamental studies of ion-solid interaction. By using a magnetic spectrometer the charge state distribution of the particles scattered from the sample after a binary collision is both possible and necessary for the analysis. For this reason the charge states are measured and compared with existing models. In addition, a model is developed that takes into account the charge state dependent energy loss. It is shown that without the application of this model the depth profiles do not correspond with the quantitative measurements by conventional IBA methods and with the thickness obtained by transmission electron microscopy. The second fundamental ion-solid interaction is the damage and the modification of the sample that occurs during

Elastic recoil atomic spectroscopy of light elements with sub-nanometer depth resolution

International Nuclear Information System (INIS)

Kosmata, Marcel

2011-01-01

In this thesis the QQDS magnetic spectrometer that is used for high resolution ion beam analysis (IBA) of light elements at the Helmholtz-Zentrum Dresden-Rossendorf is presented for the first time. In addition all parameters are investigated that influence the analysis. Methods and models are presented with which the effects can be minimised or calculated. There are five focal points of this thesis. The first point is the construction and commissioning of the QQDS magnetic spectrometer, the corresponding scattering chamber with all the peripherals and the detector, which is specially developed for high resolution elastic recoil detection. Both the reconstructed spectrometer and the detector were adapted to the specific experimental conditions needed for high-resolution Ion beam analysis of light elements and tested for routine practice. The detector consists of two components. At the back end of the detector a Bragg ionization chamber is mounted, which is used for the particle identification. At the front end, directly behind the entrance window a proportional counter is mounted. This proportional counter includes a highresistance anode. Thus, the position of the particles is determined in the detector. The following two points concern fundamental studies of ion-solid interaction. By using a magnetic spectrometer the charge state distribution of the particles scattered from the sample after a binary collision is both possible and necessary for the analysis. For this reason the charge states are measured and compared with existing models. In addition, a model is developed that takes into account the charge state dependent energy loss. It is shown that without the application of this model the depth profiles do not correspond with the quantitative measurements by conventional IBA methods and with the thickness obtained by transmission electron microscopy. The second fundamental ion-solid interaction is the damage and the modification of the sample that occurs during

PREFACE: 16th International Summer School on Vacuum, Electron, and Ion Technologies (VEIT 2009)

Science.gov (United States)

Möller, Wolfhard; Guerassimov, Nikolay; Ghelev, Chavdar

2010-04-01

The International Summer School on Vacuum, Electron and Ion Technologies (VEIT) has been organized biennially since 1977 when the series of VEIT Schools was launched by the Institute of Electronics, Bulgarian Academy of Sciences with the aim to act as a forum for interchange and dissemination of knowledge and ideas on the latest developments in electron-, ion-, and plasma-assisted technologies. Beginning from 2001, the school has been jointly organized with the Institute of Ion Beam Physics and Materials Research, Forschungszentrum Dresden-Rossendorf, Germany. Whereas, the school initially provided a meeting place for researchers mainly from Eastern and Central European countries, its importance grew issue by issue. The school is now a major scientific event and a meeting place for young scientists from Eastern and Western Europe involved in research and development associated with high-tech industries. Many former school participants have gone on to become leading scientists in research establishments and companies throughout the world. Leading international companies, such as High Voltage Engineering, Balzers, Varian, and Hauzer have used the VEIT forum to present their products through oral presentations, poster contributions or exhibits. The School Proceedings have been published in special issues of the international journals Vacuum, Plasma Processes and Polymers, Journal of Physics: Conference Series. The Sixteenth VEIT school was held in the Black Sea resort Sunny Beach, Bulgaria on 28 September to 2 October 2009. It was attended by close to 110 participants from 13 countries: Belgium, Bulgaria, Czech Republic, France, Germany, The Netherlands, Romania, Slovak Republic, Spain, Sweden, Ukraine, UK and USA. Following the tradition of publishing the VEIT Proceedings, a selection of papers presented at the event is published in this volume of Journal of Physics: Conference Series, under the originality and quality criteria of acceptance by the journal, including

Suitability study of using a coincidence monitor for room air radioactivity monitoring in a PET center

International Nuclear Information System (INIS)

Roellig, D.; Reichelt, C.; Iwatschenko-Borho, M.

2001-01-01

The application of radioactive nuclides in medicine may cause as well radioactive exposure of personnel (Medical Technical Assistants). In the present case the exposure of personnel in the area of medical positron-emission tomography (PET) within the Research Center of Rossendorf due to exhalation of the injected activity by the patient shall be investigated. For this purpose it is necessary to measure the activity concentration of the room air. Conventional methods such as collecting samples on special filters are not suitable due to the short half-life time of the used nuclides. Standard type continuous monitors are hardly suitable as well, because the injected activity of the patient and various radioactive sources required for the calibration of the PET-Camera produce an increased gamma background. In order to eliminate these disturbing influences a monitor has been constructed which uses CCM (cobalt coincidence method) developed by the company Thermo Eberline ESM. This method is specially suitable because upon each radioactive decay of PET nuclides positrons are emitted which in turn annihilate via the simultaneous emission of two 511 keV gamma quanta under an angle of 180 . The air to be measured is sucked through a cavity with two scintillation detectors on opposite sides. The coincident pulses produced by annihilating positrons inside the cavity are counted by a suitable electronic. Gamma quanta from outside the cavity can produce a pulse only in one detector and are rejected. Therefore no heavy lead shielding is required. Besides the mechanical construction of the monitor optimization and calibration for different PET-nuclides had to be performed. Special attention was paid to the sampling system. The air intake had to be close to the breathing zone of the MTA. The hose to the monitor had to be as short as possible. The target of the work was to design a model for an industrial monitor. (orig.) [de

High-performance pickups for beam diagnostics. Design, analysis, characterization and implementation

International Nuclear Information System (INIS)

Angelovski, Aleksandar

2015-01-01

This work introduces the design, analysis, characterization and implementation of high-performance pickups for two beam diagnostic instruments, a Bunch Arrival-time Monitor (BAM) and an Energy Beam Position Monitor (EBPM) at the European XFEL. As a part of the BAM the cone-shaped pickups are proposed along with the corresponding RF-frontend. The designed pickups deliver a beam induced signal with a slope steepness of around 400 mV/ps and a bandwidth of 40 GHz. These signal characteristics are well inside the design requirements, i.e., a slope steepness of 300 mV/ps and more than ten times better compared to the signal from the state-of-the-art pickups. The pickups are installed and commissioned at three accelerator facilities, FLASH at DESY, the quasi-CW SRF accelerator ELBE at the Helmholtz-Zentrum Dresden-Rossendorf and the SwissFEL injector test facility at Paul Scherrer Institute. The obtained measurement results from the installed pickups are in good agreement with the simulations. A comparison between the signal measurements with the cone-shaped pickup and the state-of-the-art is performed at ELBE showing an improvement by a factor of ten. The potential of the pickups for sub-10 fs arrival-time measurements for bunch charges of 20 pC is demonstrated at ELBE and at SwissFEL injector test facility. The introduced coneshaped pickups are the first commercially available pickups with a bandwidth of up to 40 GHz. For the EBPM, a modular pickup structure with two types of planar pickups, microstrip transmission line and grounded coplanar waveguide with perpendicular connectors is investigated. The transition region between the connector and the line is optimized for two substrate materials, alumina and glass with a reflection coefficient better than -20 dB up to 6 GHz.

Development and testing of an interface between measurement logging system and automation software DIAdem of National Instruments(NI) and water/steam material property library LibIF97

International Nuclear Information System (INIS)

Pietruske, H.; Schaffrath, A.

2002-08-01

The Institute of Safety Research (IfS) of the Forschungszentrum Rossendorf (FZR) e.V. is constructing a new large-scale multipurpose test facility TOPFLOW (Transient Two Phase Flow Test Facility). This facility will be probably put into operation in the next two months. For an effective evaluation of the start up experiments and the acceptance trials against the vendors FZR starts with the preparation of automated software tools for the measurement data logging and automation software DIAdem, which is distributed by National Instruments (NI). In a first step an interface for the coupling of a water/steam material property library LibIF97 of the University of Applied Science Zittau/Goerlitz was developed. This report describes the programming of the General Control Interface (GPI) and its coupling with DIAdem. Additionally the capability of this coupling in connection with autosequences for data evaluation was investigated. Furtheron effective methods for TOPFLOW data evaluation were demonstrated and tested against a concrete example. Currently no TOPFLOW data are available. Therefore one selected NOKO experiment was evaluated and first practical experiences were collected. Even this example is easy understandable and clearly seen, it contains every step, which is necessary for the TOPFLOW data evaluation. This contains the opening of files, determination of water/steam material properties with the Dynamic-Link-Library LibIF97.dII, the linkage of different data channels and the generation of layouts for graphics and reports. The tools presented in this report are an important step for the evaluation of the experimental data of TOPFLOW. These tools will be adapted now for the assessment of the acceptance trails. Further on now the generation of the automated software sequences for the first scientific tests are developed. (orig.) [de

Boron dilution transients during natural circulation flow in PWR-Experiments and CFD simulations

Energy Technology Data Exchange (ETDEWEB)

Hoehne, Thomas [Forschungszentrum Dresden-Rossendorf (FZD)-Institute of Safety Research, P.O. Box 510119, D-01314 Dresden (Germany)], E-mail: T.Hoehne@fzd.de; Kliem, Soeren; Rohde, Ulrich; Weiss, Frank-Peter [Forschungszentrum Dresden-Rossendorf (FZD)-Institute of Safety Research, P.O. Box 510119, D-01314 Dresden (Germany)

2008-08-15

Coolant mixing in the cold leg, downcomer and the lower plenum of pressurized water reactors is an important phenomenon mitigating the reactivity insertion into the core. Therefore, mixing of the de-borated slugs with the ambient coolant in the reactor pressure vessel was investigated at the four loops 1:5 scaled Rossendorf coolant mixing model (ROCOM) mixing test facility. In particular thermal hydraulics analyses have shown, that weakly borated condensate can accumulate in the pump loop seal of those loops, which do not receive a safety injection. After refilling of the primary circuit, natural circulation in the stagnant loops can re-establish simultaneously and the de-borated slugs are shifted towards the reactor pressure vessel (RPV). In the ROCOM experiments, the length of the flow ramp and the initial density difference between the slugs and the ambient coolant was varied. From the test matrix experiments with 0 resp. 2% density difference between the de-borated slugs and the ambient coolant were used to validate the CFD software ANSYS CFX. To model the effects of turbulence on the mean flow a higher order Reynolds stress turbulence model was employed and a mesh consisting of 6.4 million hybrid elements was utilized. Only the experiments and CFD calculations with modeled density differences show stratification in the downcomer. Depending on the degree of density differences the less dense slugs flow around the core barrel at the top of the downcomer. At the opposite side, the lower borated coolant is entrained by the colder safety injection water and transported to the core. The validation proves that ANSYS CFX is able to simulate appropriately the flow field and mixing effects of coolant with different densities.

Labelling of natural humic substances with {sup 14}C and their use in adsorption studies

Energy Technology Data Exchange (ETDEWEB)

Mansel, A.; Kupsch, H. [Institut fuer Interdisziplinaere Isotopenforschung, Permoserstr. 15, D-04318 Leipzig (Germany)

2005-07-01

Full text of publication follows: The reactive carbon compounds (humic substances, HS) of the dissolved organic matter (DOC) dominate the spreading of inorganic and organic pollutants in the bio-geosphere. The classical analytical methods such as TOC-detection and UV-spectroscopy are of limited use in the lower concentration range (< 1 mg/l), usually found in environmental samples. Based on our promising results of the HS radiolabelling with [{sup 14}C]phenyl-diazonium ions, we applied these radiolabelled substances first time to sorption studies under conditions, usually found in subterranean waste repositories. The natural HS (humic acid HA, fulvic acid FA) were purified by the IHSS-procedure. Aldrich-HA (AHA), Gorleben-HA (GoHy-573), an aquatic HA (HS3), a terrestrial HA (HS4), a lignite HA (HAL), an aquatic FA (FS3) and Gorleben-FA (GoHy-573) were used for our investigations. A synthetic HA (M42) was provided by the Forschungszentrum Rossendorf / Germany [1]. The radiolabelled HS were contacted in aqueous solution with a sandy soil (pH 5.0), granite (pH 6.0), diabase (pH 8.0) and kaolinite (pH 4.7) in batch experiments under conditions near to nature. Adsorption isotherms of various radiolabelled humic acids were determined depending on geo-material, pH, HS concentration, contact time and heavy metal content. The behaviour of the radiolabelled HS was not influenced by the labelling procedure as demonstrated by the adsorption experiments. With the use of radiolabelled humic substances a concentration range below mg/l can be studied. [1] Determination and Comparison of Uranyl Complexation Constants with Natural and Model Humic Acids. S. Pompe, A. Brachmann, M. Bubner, G. Geipel, K. H. Heise, G. Bernhard and H. Nitsche Radiochim. Acta 82, 89 (1998). (authors)

Development of a superconducting radio frequency photoelectron injector

International Nuclear Information System (INIS)

Arnold, A.; Buettig, H.; Janssen, D.; Kamps, T.; Klemz, G.; Lehmann, W.D.; Lehnert, U.; Lipka, D.; Marhauser, F.; Michel, P.; Moeller, K.; Murcek, P.; Schneider, Ch.; Schurig, R.; Staufenbiel, F.; Stephan, J.; Teichert, J.; Volkov, V.; Will, I.; Xiang, R.

2007-01-01

A superconducting radio frequency (RF) photoelectron injector (SRF gun) is under development at the Research Center Dresden-Rossendorf. This project aims mainly at replacing the present thermionic gun of the superconducting electron linac ELBE. Thereby the beam quality is greatly improved. Especially, the normalized transverse emittance can be reduced by up to one order of magnitude depending on the operating conditions. The length of the electron bunches will be shortened by about two orders of magnitude making the present bunchers in the injection beam line dispensable. The maximum obtainable bunch charge of the present thermionic gun amounts to 80pC. The SRF gun is designed to deliver also higher bunch charge values up to 2.5nC. Therefore, this gun can be used also for advanced facilities such as energy recovery linacs (ERLs) and soft X-ray FELs. The SRF gun is designed as a 312 cell cavity structure with three cells basically TESLA cells supplemented by a newly developed gun cell and a choke filter. The exit energy is projected to be 9.5MeV. In this paper, we present a description of the design of the SRF gun with special emphasis on the physical and technical problems arising from the necessity of integrating a photocathode into the superconducting cavity structure. Preparation, transfer, cooling and alignment of the photocathode are discussed. In designing the SRF gun cryostat for most components wherever possible the technical solutions were adapted from the ELBE cryostat in some cases with major modifications. As concerns the status of the project the design is finished, most parts are manufactured and the gun is being assembled. Some of the key components are tested in special test arrangements such as cavity warm tuning, cathode cooling, the mechanical behavior of the tuners and the effectiveness of the magnetic screening of the cavity

Integration of DYN3D inside the NURESIM platform

International Nuclear Information System (INIS)

Gomez T, A. M.; Sanchez E, V. H.; Kliem, S.; Gommlich, A.; Rohde, U.

2010-10-01

The NURISP project (Nuclear Reactor Integrated Simulation Project) is focused on the further development of the European Nuclear Reactor Simulation (NURESIM) platform for advanced numerical reactor design and safety analysis tools. NURESIM is based on an open source platform - called SALOME - that offers flexible and powerful capabilities for pre- and post processing as well as for coupling of multi-physics and multi-scale solutions. The developments within the NURISP project are concentrated in the areas of reactors, physics, thermal hydraulics, multi-physics, and sensitivity and uncertainty methodologies. The aim is to develop experimentally validated advanced simulation tools including capabilities for uncertainty and sensitivity quantification. A unique feature of NURESIM is the flexibility in selecting the solvers for the area of interest and the interpolation and mapping schemes according to the problem under consideration. The Sub Project 3 (S P3) of NURISP is focused on the development of multi-physics methodologies at different scales and covering different physical fields (neutronics, thermal hydraulics and pin mechanics). One of the objectives of S P3 is the development of multi-physics methodologies beyond the state-of-the-art for improved prediction of local safety margins and design at pin-by-pin scale. The Karlsruhe Institute of Technology and the Research Center Dresden-Rossendorf are involved in the integration of the reactor dynamics code DYN3D into the SALOME platform for coupling with a thermal hydraulic sub-channel code (FLICA4) at fuel assembly and pin level. In this paper, the main capabilities of the SALOME platform, the steps for the integration process of DYN3D as well as selected preliminary results obtained for the DYN3D/FLICA4 coupling are presented and discussed. Finally the next steps for the validation of the coupling scheme at fuel assembly and pin basis are given. (Author)

CFD modelling of polydispersed bubbly two-phase flow around an obstacle

International Nuclear Information System (INIS)

Krepper, Eckhard; Beyer, Matthias; Frank, Thomas; Lucas, Dirk; Prasser, Horst-Michael

2009-01-01

A population balance model (the Inhomogeneous MUSIG model) has recently been developed in close cooperation between ANSYS-CFX and Forschungszentrum Dresden-Rossendorf and implemented into the CFD-Code CFX [Krepper, E., Lucas, D., Prasser, H.-M, 2005. On the modelling of bubbly flow in vertical pipes. Nucl. Eng. Des. 235, 597-611; Frank, T., Zwart, P.J., Shi, J.-M., Krepper, E., Rohde, U., 2005. Inhomogeneous MUSIG Model-a population balance approach for polydispersed bubbly flows, International Conference 'Nuclear Energy for New Europe 2005', Bled, Slovenia, September 5-8, 2005; Krepper, E., Beyer, M., Frank, Th., Lucas, D., Prasser, H.-M., 2007. Application of a population balance approach for polydispersed bubbly flows, 6th Int. Conf. on Multiphase Flow Leipzig 2007, (paper 378)]. The current paper presents a brief description of the model principles. The capabilities of this model are discussed via the example of a bubbly flow around a half-moon shaped obstacle arranged in a 200 mm pipe. In applying the Inhomogeneous MUSIG approach, a deeper understanding of the flow structures is possible and the model allows effects of polydispersion to be investigated. For the complex flow around the obstacle, the general structure of the flow was well reproduced in the simulations. This test case demonstrates the complicated interplay between size dependent bubble migration and the effects of bubble coalescence and breakup on real flows. The closure models that characterize the bubble forces responsible for the simulation of bubble migration show agreement with the experimental observations. However, clear deviations occur for bubble coalescence and fragmentation. The models applied here, which describe bubble fragmentation and coalescence could be proved as a weakness in the validity of numerous CFD analyses of vertical upward two-phase pipe flow. Further work on this topic is under way.

Local and integral ulrasonic gauges for two-phase flow instrumentation in nuclear reactor and safety technology. Final report

International Nuclear Information System (INIS)

Chochlov, V.N.; Duncev, A.V.; Ivanov, V.V.; Kontelev, V.V.; Melnikov, V.I.; Stoppel, L.K.; Prasser, H.M.; Zippe, W.; Zschau, J.; Zboray, R.

2000-11-01

The present project was executed in the frame of a co-operation agreement between FZR and the scientific group of Prof. Melnikov of the technical University of Nishny Novgorod (TUNN) in the Russian Federation. It is part of the Federal Government's programme for the provision of advice for Eastern Europe on the building up of democracy and social market economy (TRANSFORM Programme). New methods of two-phase flow instrumentation were developed: Intrusive wave-guide probes can be used for local void fraction measurements. The new ultrasonic mesh sensors allow a fast two-phase flow visualisation with about 250 frames per second. Experiments carried out at the test loop in Rossendorf, but also the tests at the DESIRE facility in Delft have shown that both local wave-guide probes and ultrasonic mesh sensors can be successfully applied under the conditions of high pressure and temperature steam-water mixture, as well as in organic liquids and refrigerants. Furthermore, non-intrusive wave-guide sensors as well as density sensors based on the measurement of the wave propagation velocity in wave-guides immersed into the measuring liquid were developed and tested. In the present stage of the development, the non-intrusive sensors can rather be used for a qualitative gas respectively level detection than for void fraction measurements. The wave-guide density sensor was successfully demonstrated that it is able to measure densities of single-phase liquids. It requires further development of the electronic circuitry. The main innovation was achieved by the development of the ultrasonic mesh sensor, the resoluting capability of which is comparable to methods like electrical wire-mesh sensors and ultra-fast X-ray tomography, while the device itself is robust and low expensive. (orig.) [de

Photo-neutron reaction cross-section for 93Nb in the end-point bremsstrahlung energies of 12–16 and 45–70 MeV

International Nuclear Information System (INIS)

Naik, H.; Kim, G.N.; Schwengner, R.; Kim, K.; Zaman, M.; Tatari, M.; Sahid, M.; Yang, S.C.; John, R.; Massarczyk, R.; Junghans, A.; Shin, S.G.; Key, Y.; Wagner, A.; Lee, M.W.; Goswami, A.; Cho, M.-H.

2013-01-01

The photo-neutron cross-sections of 93 Nb at the end-point bremsstrahlung energies of 12, 14 and 16 MeV as well as 45, 50, 55, 60 and 70 MeV have been determined by the activation and the off-line γ-ray spectrometric techniques using the 20 MeV electron linac (ELBE) at Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden, Germany, and 100 MeV electron linac at Pohang Accelerator Laboratory (PAL), Pohang, Korea. The 93 Nb(γ, xn, x=1–4) reaction cross-sections as a function of photon energy were also calculated using computer code TALYS 1.4. The flux-weighted average values were obtained from the experimental and the theoretical (TALYS) values based on mono-energetic photons. The experimental values of present work are in good agreement with the flux-weighted theoretical values of TALYS 1.4 but are slightly higher than the flux-weighted experimental data of mono-energetic photons. It was also found that the theoretical and the experimental values of present work and literature data for the 93 Nb(γ, xn) reaction cross-sections increase from the threshold values to a certain energy, where other reaction channels opens. However, the increase of 93 Nb(γ, n) and 93 Nb(γ, 2n) reaction cross-sections are sharper compared to 93 Nb(γ, 3n) and 93 Nb(γ, 4n) reaction cross-sections. The sharp increase of 93 Nb(γ, n) and 93 Nb(γ, 2n) reaction cross-sections from the threshold value up to 17–22 MeV is due to the Giant Dipole Resonance (GDR) effect besides the role of excitation energy. After a certain values, the individual 93 Nb(γ, xn) reaction cross-sections decrease with increase of bremsstrahlung energy due to opening of other reaction channels

CFD-calculations to a core catcher benchmark

International Nuclear Information System (INIS)

Willschuetz, H.G.

1999-04-01

There are numerous experiments for the exploration of the corium spreading behaviour, but comparable data have not been available up to now in the field of the long term behaviour of a corium expanded in a core catcher. The difficulty consists in the experimental simulation of the decay heat that can be neglected for the short-run course of events like relocation and spreading, which must, however, be considered during investigation of the long time behaviour. Therefore the German GRS, defined together with Battelle Ingenieurtechnik a benchmark problem in order to determine particular problems and differences of CFD codes simulating an expanded corium and from this, requirements for a reasonable measurement of experiments, that will be performed later. First the finite-volume-codes Comet 1.023, CFX 4.2 and CFX-TASCflow were used. To be able to make comparisons to a finite-element-code, now calculations are performed at the Institute of Safety Research at the Forschungszentrum Rossendorf with the code ANSYS/FLOTRAN. For the benchmark calculations of stage 1 a pure and liquid melt with internal heat sources was assumed uniformly distributed over the area of the planned core catcher of a EPR plant. Using the Standard-k-ε-turbulence model and assuming an initial state of a motionless superheated melt several large convection rolls will establish within the melt pool. The temperatures at the surface do not sink to a solidification level due to the enhanced convection heat transfer. The temperature gradients at the surface are relatively flat while there are steep gradients at the ground where the no slip condition is applied. But even at the ground no solidification temperatures are observed. Although the problem in the ANSYS-calculations is handled two-dimensional and not three-dimensional like in the finite-volume-codes, there are no fundamental deviations to the results of the other codes. (orig.)

Annual report 2011. Institute of Ion Beam Physics and Materials Research

International Nuclear Information System (INIS)

Cordeiro, A.L.; Fassbender, J.; Heera, V.; Helm, M.

2012-01-01

The first year of membership of the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) in the Helmholtz Association of German Research Centers (HGF) was a year of many changes also for the Institute of Ion Beam Physics and Materials Research (IIM). The transition period, however, is not yet over, since the full integration of the Center into the HGF will only be completed in the next period of the so-called program-oriented funding (POF). This funding scheme addresses the six core research fields identified by the Helmholtz Association (Energy; Earth and Environment; Health; Key Technologies; Structure of Matter; Aeronautics, Space and Transport) to deal with the grand challenges faced by society, science and industry. Since the Institute has strong contributions to both core fields ''Key Technologies'' and ''Structure of Matter'', intense discussions were held amongst the leading scientists of the Institute, across the Institutes of the HZDR, and finally with leading scientists of other Helmholtz centers, to determine the most appropriate classification of the Institute's research. At the end we decided to establish ourselves in Structure of Matter, the core field in which most of the large-scale photon, neutron and ion facilities in Germany are located. As a consequence, the Ion Beam Center (IBC) of the Institute submitted an application to become a HGF recognized large-scale facility, providing more than 50% of its available beam time to external users. This application perfectly reflects the development of the IBC over more than a decade as a European Union funded infrastructure in the framework of the projects ''Center for Application of Ion Beams in Materials Research (AIM)'' (1998-2000, 2000-2003, 2006-2010) and subsequently as the coordinator of the integrated infrastructure initiative (I3) ''Support of Public and Industrial Research using Ion Beam Technology (SPIRIT)'' (2009-2013). Another part of the Institute's activities is dedicated to exploit the infrared

The new 6 MV AMS-facility DREAMS at Dresden

International Nuclear Information System (INIS)

Akhmadaliev, Shavkat; Heller, René; Hanf, Daniel; Rugel, Georg; Merchel, Silke

2013-01-01

Highlights: ► New 6 MV tandem accelerator in operation in Germany for AMS, IBA and HE-implantation. ► DREsden AMS (DREAMS) primarily used for radionuclides 10 Be, 26 Al, 36 Cl, 41 Ca and 129 I. ► Quality assurance by traceable calibration materials and interlaboratory comparisons. High accuracy data for future DREAMS users. ► Energy calibration of accelerator by 1 H( 15 N,γα) 12 C yield correction factor of 1.019. - Abstract: A new 6 MV electrostatic tandem accelerator has been put into operation at Helmholtz-Zentrum Dresden-Rossendorf (HZDR). The system is equipped for accelerator mass spectrometry and opens a new research field at HZDR and the Helmholtz Association. It will be also used for ion beam analysis as well as for material modification via high-energy ion implantation. The research activity at the DREsden Accelerator Mass Spectrometry facility (DREAMS) based on a 6 MV Tandetron is primarily dedicated to the long-lived radioisotopes of 10 Be, 26 Al, 36 Cl, 41 Ca, and 129 I. DREAMS background levels have been found to be at 4.5 × 10 −16 for 10 Be/ 9 Be, 8 × 10 −16 for 26 Al/ 27 Al, 3 × 10 −15 for 36 Cl/ 35 Cl and 8 × 10 −15 for 41 Ca/ 40 Ca, respectively. The observed background of 2 × 10 −13 for 129 I/ 127 I originates from intrinsic 129 I from AgI produced from commercial KI. The introduction of quality assurance approaches for AMS, such as the use of traceable calibration materials and taking part in interlaboratory comparisons, guarantees high accuracy data for future DREAMS users. During first experiments an energy calibration of the accelerator has been carried out using the nuclear reaction 1 H( 15 N,γα) 12 C yielding an energy correction factor of 1.019.

Test of Compton camera components for prompt gamma imaging at the ELBE bremsstrahlung beam

Science.gov (United States)

Hueso-González, F.; Golnik, C.; Berthel, M.; Dreyer, A.; Enghardt, W.; Fiedler, F.; Heidel, K.; Kormoll, T.; Rohling, H.; Schöne, S.; Schwengner, R.; Wagner, A.; Pausch, G.

2014-05-01

In the context of ion beam therapy, particle range verification is a major challenge for the quality assurance of the treatment. One approach is the measurement of the prompt gamma rays resulting from the tissue irradiation. A Compton camera based on several position sensitive gamma ray detectors, together with an imaging algorithm, is expected to reconstruct the prompt gamma ray emission density map, which is correlated with the dose distribution. At OncoRay and Helmholtz-Zentrum Dresden-Rossendorf (HZDR), a Compton camera setup is being developed consisting of two scatter planes: two CdZnTe (CZT) cross strip detectors, and an absorber consisting of one Lu2SiO5 (LSO) block detector. The data acquisition is based on VME electronics and handled by software developed on the ROOT framework. The setup has been tested at the linear electron accelerator ELBE at HZDR, which is used in this experiment to produce bunched bremsstrahlung photons with up to 12.5 MeV energy and a repetition rate of 13 MHz. Their spectrum has similarities with the shape expected from prompt gamma rays in the clinical environment, and the flux is also bunched with the accelerator frequency. The charge sharing effect of the CZT detector is studied qualitatively for different energy ranges. The LSO detector pixel discrimination resolution is analyzed and it shows a trend to improve for high energy depositions. The time correlation between the pulsed prompt photons and the measured detector signals, to be used for background suppression, exhibits a time resolution of 3 ns FWHM for the CZT detector and of 2 ns for the LSO detector. A time walk correction and pixel-wise calibration is applied for the LSO detector, whose resolution improves up to 630 ps. In conclusion, the detector setup is suitable for time-resolved background suppression in pulsed clinical particle accelerators. Ongoing tasks are the quantitative comparison with simulations and the test of imaging algorithms. Experiments at proton

Test of Compton camera components for prompt gamma imaging at the ELBE bremsstrahlung beam

International Nuclear Information System (INIS)

Hueso-González, F; Golnik, C; Berthel, M; Dreyer, A; Enghardt, W; Kormoll, T; Rohling, H; Pausch, G; Fiedler, F; Heidel, K; Schöne, S; Schwengner, R; Wagner, A

2014-01-01

In the context of ion beam therapy, particle range verification is a major challenge for the quality assurance of the treatment. One approach is the measurement of the prompt gamma rays resulting from the tissue irradiation. A Compton camera based on several position sensitive gamma ray detectors, together with an imaging algorithm, is expected to reconstruct the prompt gamma ray emission density map, which is correlated with the dose distribution. At OncoRay and Helmholtz-Zentrum Dresden-Rossendorf (HZDR), a Compton camera setup is being developed consisting of two scatter planes: two CdZnTe (CZT) cross strip detectors, and an absorber consisting of one Lu 2 SiO 5 (LSO) block detector. The data acquisition is based on VME electronics and handled by software developed on the ROOT framework. The setup has been tested at the linear electron accelerator ELBE at HZDR, which is used in this experiment to produce bunched bremsstrahlung photons with up to 12.5 MeV energy and a repetition rate of 13 MHz. Their spectrum has similarities with the shape expected from prompt gamma rays in the clinical environment, and the flux is also bunched with the accelerator frequency. The charge sharing effect of the CZT detector is studied qualitatively for different energy ranges. The LSO detector pixel discrimination resolution is analyzed and it shows a trend to improve for high energy depositions. The time correlation between the pulsed prompt photons and the measured detector signals, to be used for background suppression, exhibits a time resolution of 3 ns FWHM for the CZT detector and of 2 ns for the LSO detector. A time walk correction and pixel-wise calibration is applied for the LSO detector, whose resolution improves up to 630 ps. In conclusion, the detector setup is suitable for time-resolved background suppression in pulsed clinical particle accelerators. Ongoing tasks are the quantitative comparison with simulations and the test of imaging algorithms. Experiments at proton

The German P and T Study: Results and Conclusions in the View of the Contributing Helmholtz Research Centres

International Nuclear Information System (INIS)

Merk, B.; Geist, A.; Knebel, J.; Modolo, G.

2015-01-01

The decision to phase out electric energy production in nuclear power plants in Germany has put some questions on the future of P and T research. The Federal Ministry for Economic Affairs and Energy and the Federal Ministry of Education and Research have launched a study managed by the National Academy of Science and Engineering to answer these questions on a broad scientific basis. The major mandate was to evaluate scientific and technological as well as socio-economic challenges and opportunities of the P and T technology in the view of the phase out decision, both in a national and an international context. The scientific and technological aspects of P and T are analysed with respect to a possible contribution to the management of nuclear waste, using the following structure: - Starting point and boundary conditions - waste amounts and final disposal strategies. - Definition and description of scenarios - possible ways for transmutation; European vs. national. - Technology challenges of P and T - description of the major challenges to be solved on the way to a possible industrial application. - Current status of R and D - discussion of possible transmutation systems, current R and D status of P and T, technology gaps and future research strategies. - Safety aspects - dedicated safety aspects including all steps of the P and T cycle. - International projects and competences in Germany - what is going on around the world and which support could come from the German industry? In parallel, the socio-scientific, the ecologic and the economic aspects have been analysed using expert interviews, group Delphi and independent expert opinions on economic, legal and environmental aspects. An overview of the study's results will be given from the viewpoint of the contributing Helmholtz research centres at Juelich (FZJ), Dresden-Rossendorf (HZDR) and Karlsruhe (KIT), with a focus on the research-political recommendations and the developed research strategy proposed to

The German competence network on nuclear technology

International Nuclear Information System (INIS)

Kuczera, B.; Fritz, P.

2004-01-01

Full text: The present German energy policy is based on the phase-out of nuclear electricity generation, which means that the last of the currently operating eighteen German nuclear power plants will run until about 2022. While the plants will be shut down one after the other, decommissioning will start together with interim storage of the radioactive waste. The safe waste disposal in a final repository is planned to start around 2030 and may take another two decades, i.e., in Germany nuclear competence is further needed, at least until the mid of this century. Against this background, a high-ranking commission under the direction of the Federal Ministry of Economy and Technology evaluated the publicly funded nuclear safety related research and development (R and D) activities in Germany. One of the recommendations made by the commission was the foundation of a Competence Network on Nuclear Technology for an optimum coordination of the remaining nuclear activities including aspects of future human resources in this area. This Network was established in March 2000 with the following member institutions: Research Centre Juelich, Research Centre Karlsruhe, Research Centre Rossendorf and the Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) in Munich and their neighbouring Technical Universities. The strategic objectives of the Competence Network include: Trend investigations on job development and on university education capacities in the nuclear technology sector; Enhanced cooperation of the Research Centres with universities in the nuclear field and support of international education initiatives (e.g. ENEN, WNU); Coordination and bundling of the activities in publicly funded reactor safety and waste management R and D programmes; Support of qualified young scientists and engineers (pre-doctoral students) - also by third-party funds; Participation in and collaboration with international projects and activities for advancements of international nuclear safety

Department of Nuclear Reactions - Overview

International Nuclear Information System (INIS)

Nowicki, L.

2006-01-01

In 2005 the Department held a steady course. Topics of nuclear physics, atomic physics and materials research that started in previous years were continued. Although our team was smaller than years ago, the scientific activity, estimated by number of published papers is still very high. Scientists of the Department are co-authors or authors of more than 50 papers. Nuclear physics, which is our main-stream activity, covered a wide energy range. It started close to the Coulomb barrier, where 6 He breakup on heavy nuclei were studied, and ended at zones of tens of GeV; such high energies were used to investigate spin structure of deuterons and to explore hadron leptoproduction. Traditionally, experimental investigations in the fields of atomic physics and of physics of materials completed the scene. Our old Van de Graaff accelerator Lech was used for studies of M-shell ionisation of heavy elements, for hardening of Ultra-High Molecular Weight Polyethylene and for characterisation of materials with RBS and NRA techniques. The VdG runs perfectly although it is over 40 years old. Two Ph.D. students finished their theses and were promoted. Izabela Fijal's work concerned multi-ionization and intrashell coupling effects for L-shell x-ray emission induced by heavy ions, while Sergiy Mezhevych showed studies on scattering of 11 B from carbon isotopes. It is obvious that contemporary works on physics do not arise in a single lab. Our contributions to many papers were possible due owing to collaborations involving many institutions. Some of them are listed: GSI, Darmstadt (PANDA Collaboration) DESY, Hamburg (HERMES Collaboration) Institut fuer Kernphysik, Forschungszentrum Juelich Forschungszentrum Rossendorf CSNSM, Orsay GANIL, Caen University of Huelva Institute of Nuclear Research, Kiev SLCJ, Warsaw ITME, Warsaw Some of our colleagues traditionally gave lectures and made physical demonstrations on Warsaw informal learning events: 9 th Science Picnic and 9 th Science Festival

Interpretation of uranium and thorium excretion data taking into account excretion data caused by natural sources

International Nuclear Information System (INIS)

Sahre, P.; Schoenmuth, Th.; Helling, K.

2000-01-01

At the Nuclear Engineering and Analytics Inc. Rossendorf near Dresden (Germany) occupationally exposed persons are working with Uranium and Thorium. In accordance with German guides urine and faecal analysis is carried out. But for the interpretation the data in terms of dose or intake it is important to have knowledge about the portion of the activity measured caused by natural sources. For this reason 16 occupationally exposed persons who did not have any history of occupational exposure to Thorium or Uranium have been checked concerning the excretion data since 1994. The excretion data in mBq per day for all persons covers the following ranges: Faeces: U-234 1 to 310 mBq/d, U-235 0.2 to 3.7 mBq/d, U-238 1.3 to 72 mBq/d. Th-228 7 to 89 mBq/d, Th-230 0.7 to 19 mBq/d, Th-232 0.7 to 16 mBq/d. Urine: all values below the detection limits of about 1 mBq/l. The large variation results from differences between the individual excretion rates but also from the variation of the excretion rate of one person. For example, the U-234-faecal excretion of one person reaches from 77 to 310 mBq per day. In the paper the faecal excretion for some individuals in dependence on the time are given. These excretion date caused by natural sources are taken into account by interpreting faecal excretion data of occupationally exposed persons working with Uranium or Thorium. If the measured faecal excretion per day is within the range caused by natural sources no interpretation will be done. By exceeding these values additional faeces and urine samples will be collected and measured. In dependence on these additional results intake and dose will be assessed some times by using lung counter or whole body counter measuring results. In the paper some examples are described. (author)

Utilization of nuclear research reactors

International Nuclear Information System (INIS)

1980-01-01

Full text: Report on an IAEA interregional training course, Budapest, Hungary, 5-30 November 1979. The course was attended by 19 participants from 16 Member States. Among the 28 training courses which the International Atomic Energy Agency organized within its 1979 programme of technical assistance was the Interregional Training Course on the Utilization of Nuclear Research Reactors. This course was held at the Nuclear Training Reactor (a low-power pool-type reactor) of the Technical University, Budapest, Hungary, from 5 to 30 November 1979 and it was complemented by a one-week Study Tour to the Nuclear Research Centre in Rossendorf near Dresden, German Democratic Republic. The training course was very successful, with 19 participants attending from 16 Member States - Bangladesh, Bolivia, Czechoslovakia, Ecuador, Egypt, India, Iraq, Korean Democratic People's Republic, Morocco, Peru, Philippines, Spain, Thailand, Turkey, Vietnam and Yugoslavia. Selected invited lecturers were recruited from the USA and Finland, as well as local scientists from Hungarian institutions. During the past two decades or so, many research reactors have been put into operation around the world, and the demand for well qualified personnel to run and fully utilize these facilities has increased accordingly. Several developing countries have already acquired small- and medium-size research reactors mainly for isotope production, research in various fields, and training, while others are presently at different stages of planning and installation. Through different sources of information, such as requests to the IAEA for fellowship awards and experts, it became apparent that many research reactors and their associated facilities are not being utilized to their full potential in many of the developing countries. One reason for this is the lack of a sufficient number of trained professionals who are well acquainted with all the capabilities that a research reactor can offer, both in research and

Calculation of the emergency condenser of the indirect cycle reactor CAREM

International Nuclear Information System (INIS)

Walter, D.; Schaffrath, A.

2002-08-01

CAREM is an Argentine project to achieve the development, design and construction of an innovative, simple and small Nuclear Power Plant (NPP). This NPP has an indirect cycle reactor with some distinctive and characteristic features (e.g. integrated primary cooling system by natural circulation, self-pressurized primary system and passive safety systems, etc.). In the frame of an IAEA forwarded HUMAN RESOURCES DEVELOPMENT - 'Advice on CAREM passive emergency condenser' at the Centro Atomico in San Carlos de Bariloche (Argentina) German experimental as well as analytical investigations of passive safety systems - mainly performed at the research centers Juelich and Rossendorf - were presented. During this visit it was decided that FZR should determine the emergency condenser capacity by using the ATHLET code with and without the condensation module extension KONWAR (condensation inside horizontal tube). These results should be compared and assessed with existing RELAP calculations. The ATHLET and ATHLET/KONWAR calculations of the emergency condenser were used for minimizing the user influence performed with exactly the same nodalization scheme and the same initial and boundary conditions than the RELAP calculations. The comparison of all three computational results shows that the required condenser capacities were achieved. The magnitudes were in order of up to 12%. An additionally performed evaluation of local flow parameters show large deviations especially for the heat transfer coefficients at the inner and outer tube wall. Due to the good validation progress of KONWAR by an extensive module validation against NOKO and HORUS experiments, the focus of the further investigation were concentrated on the boiling heat transfer. A comparison of the ATHLET boiling model (according to Forster and Zuber in combination with the equation of Thom for the determination of temperature difference between wall and saturated fluid) with other models from literature (Borishansky

Nuclear safety research in HGF 2012

International Nuclear Information System (INIS)

Anon.

2013-01-01

Nuclear Competence Association. The Forschungszentrum Juelich GmbH, HZDR Helmholtz-Zentrum Dresden-Rossendorf and the KIT Karlsruhe Institute of Technology are involved in the Nuclear Safety Research Program within the Helmholtz Association. The work and results in 2012 are presented. (orig.)

Nuclear Legislation in OECD and NEA Countries. Regulatory and Institutional Framework for Nuclear Activities - Germany

International Nuclear Information System (INIS)

2011-01-01

Committee - KTA); 3. Public and semi-public agencies (Technological Surveillance Association - Technische Ueberwachungsvereine-TUV; Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS)mbH; Karlsruhe Research Centre - Forschungszentrum Karlsruhe; Juelich Research Centre - Forschungszentrum Juelich GmbH; GKSS Research Centre Geesthacht - Forschungszentrum Geesthacht GmbH; Helmholtz Zentrum Berlin for Materials and Energy; The Electron-Synchrotron in Hamburg - Deutsches Elektronen-Synchrotron-DESY; Max-Planck Institute for Plasma Physics at Garching/Munich - Max-Planck-Institut fuer Plasmaphysik-IPP; Company for Heavy Ion Research - Gesellschaft fuer Schwerionenforschung mbH-GSI; Rossendorf Association for Nuclear Technology and Analysis - Verein fuer Kernverfahrenstechnik und Anlaytik)

Development of a general coupling interface for the fuel performance code transuranus tested with the reactor dynamic code DYN3D

International Nuclear Information System (INIS)

Holt, L.; Rohde, U.; Seidl, M.; Schubert, A.; Van Uffelen, P.

2013-01-01

Several institutions plan to couple the fuel performance code TRANSURANUS developed by the European Institute for Transuranium Elements with their own codes. One of these codes is the reactor dynamic code DYN3D maintained by the Helmholtz-Zentrum Dresden - Rossendorf. DYN3D was developed originally for VVER type reactors and was extended later to western type reactors. Usually, the fuel rod behavior is modeled in thermal hydraulics and neutronic codes in a simplified manner. The main idea of this coupling is to describe the fuel rod behavior in the frame of core safety analysis in a more detailed way, e.g. including the influence of the high burn-up structure, geometry changes and fission gas release. It allows to take benefit from the improved computational power and software achieved over the last two decades. The coupling interface was developed in a general way from the beginning. Thence it can be easily used also by other codes for a coupling with TRANSURANUS. The user can choose between a one-way as well as a two-way online coupling option. For a one-way online coupling, DYN3D provides only the time-dependent rod power and thermal hydraulics conditions to TRANSURANUS, but the fuel performance code doesn’t transfer any variable back to DYN3D. In a two-way online coupling, TRANSURANUS in addition transfers parameters like fuel temperature and cladding temperature back to DYN3D. This list of variables can be extended easily by geometric and further variables of interest. First results of the code system DYN3D-TRANSURANUS will be presented for a control rod ejection transient in a modern western type reactor. Pre-analyses show already that a detailed fuel rod behavior modeling will influence the thermal hydraulics and thence also the neutronics due to the Doppler reactivity effect of the fuel temperature. The coupled code system has therefore a potential to improve the assessment of safety criteria. The developed code system DYN3D-TRANSURANUS can be used also

Zinc corrosion after loss-of-coolant accidents in pressurized water reactors – Thermo- and fluid-dynamic effects

Energy Technology Data Exchange (ETDEWEB)

Seeliger, André, E-mail: a.seeliger@hszg.de [Hochschule Zittau/Görlitz, Institute of Process Technology, Process Automation and Measuring Technology, Theodor-Körner-Allee 16, D-02763 Zittau (Germany); Alt, Sören; Kästner, Wolfgang; Renger, Stefan [Hochschule Zittau/Görlitz, Institute of Process Technology, Process Automation and Measuring Technology, Theodor-Körner-Allee 16, D-02763 Zittau (Germany); Kryk, Holger; Harm, Ulrich [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Fluid Dynamics, P.O. Box 510119, D-01314 Dresden (Germany)

2016-08-15

Highlights: • Borated coolant supports corrosion at zinc-coated installations in PWR after LOCA. • Dissolved zinc is injected into core by ECCS during sump recirculation phase. • Corrosion products can reach and settle at further downstream components. • Corrosion products can cause head losses at spacers and influence decay heat removal. • Preventive procedures were tested at semi-technical scale facilities. - Abstract: Within the framework of the German reactor safety research, generic experimental investigations were carried out aiming at thermal-hydraulic consequences of physicochemical mechanisms, caused by dissolution of zinc in boric acid during corrosion processes at hot-dip galvanized surfaces of containment internals at lower coolant temperatures and the subsequent precipitation of solid zinc borates in PWR core regions of higher temperature. This constellation can occur during sump recirculation operation of ECCS after LOCA. Hot-dip galvanized compounds, which are installed inside a PWR containment, may act as zinc sources. Getting in contact with boric acid coolant, zinc at their surfaces is released into coolant in form of ions due to corrosion processes. As a long-term behavior resp. over a time period of several days, metal layers of zinc and zinc alloys can dissolve extensively. First fundamental studies at laboratory scale were done at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR). Their experimental results were picked up for the definition of boundary conditions for experiments at semi-technical scale at the Hochschule Zittau/Görlitz (HSZG). Electrical heating rods with zircaloy cladding tubes have been used as fuel rod simulators. As near-plant core components, a 3 × 3 configuration of heating rods (HRC) and a shortened, partially heatable PWR fuel assembly dummy were applied into cooling circuits. The HRC module includes segments of spacers for a suitable representation of a heating channel geometry. Formations of different solid

Study on partitioning and transmutation (P and T) of high-level waste. Status of R and D. Final report; Studie zur Partitionierung und Transmutation (P and T) hochradioaktiver Abfaelle. Stand der Grundlagen- und technologischen Forschung. Abschlussbericht

Energy Technology Data Exchange (ETDEWEB)

Merk, Bruno; Glivici-Cotruta, Varvara

2014-07-01

The main project, where this sub project contributed to, has been structured into two modules: module A (funded by the federal ministry of economics, managed by KIT) and module B (funded by the federal ministry of education and research, managed by acatech). Partners in module A were DBE TECHNOLOGY GmbH, the Gesellschaft fuer Anlagen- und Reaktorsicherheit mbH (GRS), the Helmholtz-Zentrum Dresden-Rossendorf (HZDR), the Karlsruher Institute of Technology (KIT) and the Rheinisch-Westfaelische Technische Hochschule (RWTH) Aachen, in co-operation with the Forschungszentrum Juelich (FZJ). Modul B has been executed by the Zentrum fuer Interdisziplinaere Risiko- und Innovationsforschung der Universitaet Stuttgart (ZIRIUS). The overall coordination has been carried out by the Deutsche Akademie der Technikwissenschaften (acatech). The social implications have been evaluated in module B based on the analysis of the scientific and technological aspects in module A. Recommendations for communication and actions to be taken for the future positioning of P and T have been developed. In the project part, coordinated by HZDR - status of R and D - an overview on the whole topic P and T is given. The topic is opened by a short description of reactor systems possible for transmutation. In the following the R and D status of separation technologies, safety technology, accelerator technology, liquid metal technology, spallation target development, transmutation fuel and structural material development, as well as waste conditioning is described. The topic is completed by the specifics of transmutation systems, the basic physics and core designs, the reactor physics, the simulation tools and the development of Safety Approaches. Additionally, the status of existing irradiation facilities with fast neutron spectrum is described. Based on the current R and D status, the research and technology gaps in the topics: separation and conditioning, accelerator and spallation target, and reactor

Coolant Mixing in a Pressurized Water Reactor: Deboration Transients, Steam-Line Breaks, and Emergency Core Cooling Injection

International Nuclear Information System (INIS)

Prasser, Horst-Michael; Grunwald, Gerhard; Hoehne, Thomas; Kliem, Soeren; Rohde, Ulrich; Weiss, Frank-Peter

2003-01-01

The reactor transient caused by a perturbation of boron concentration or coolant temperature at the inlet of a pressurized water reactor (PWR) depends on the mixing inside the reactor pressure vessel (RPV). Initial steep gradients are partially lessened by turbulent mixing with coolant from the unaffected loops and with the water inventory of the RPV. Nevertheless the assumption of an ideal mixing in the downcomer and the lower plenum of the reactor leads to unrealistically small reactivity inserts. The uncertainties between ideal mixing and total absence of mixing are too large to be acceptable for safety analyses. In reality, a partial mixing takes place. For realistic predictions it is necessary to study the mixing within the three-dimensional flow field in the complicated geometry of a PWR. For this purpose a 1:5 scaled model [the Rossendorf Coolant Mixing Model (ROCOM) facility] of the German PWR KONVOI was built. Compared to other experiments, the emphasis was put on extensive measuring instrumentation and a maximum of flexibility of the facility to cover as much as possible different test scenarios. The use of special electrode-mesh sensors together with a salt tracer technique provided distributions of the disturbance within downcomer and core entrance with a high resolution in space and time. Especially, the instrumentation of the downcomer gained valuable information about the mixing phenomena in detail. The obtained data were used to support code development and validation. Scenarios investigated are the following: (a) steady-state flow in multiple coolant loops with a temperature or boron concentration perturbation in one of the running loops, (b) transient flow situations with flow rates changing with time in one or more loops, such as pump startup scenarios with deborated slugs in one of the loops or onset of natural circulation after boiling-condenser-mode operation, and (c) gravity-driven flow caused by large density gradients, e.g., mixing of cold

Study on partitioning and transmutation (P and T) of high-level waste. Status of R and D. Final report

International Nuclear Information System (INIS)

Merk, Bruno; Glivici-Cotruta, Varvara

2014-01-01

The main project, where this sub project contributed to, has been structured into two modules: module A (funded by the federal ministry of economics, managed by KIT) and module B (funded by the federal ministry of education and research, managed by acatech). Partners in module A were DBE TECHNOLOGY GmbH, the Gesellschaft fuer Anlagen- und Reaktorsicherheit mbH (GRS), the Helmholtz-Zentrum Dresden-Rossendorf (HZDR), the Karlsruher Institute of Technology (KIT) and the Rheinisch-Westfaelische Technische Hochschule (RWTH) Aachen, in co-operation with the Forschungszentrum Juelich (FZJ). Modul B has been executed by the Zentrum fuer Interdisziplinaere Risiko- und Innovationsforschung der Universitaet Stuttgart (ZIRIUS). The overall coordination has been carried out by the Deutsche Akademie der Technikwissenschaften (acatech). The social implications have been evaluated in module B based on the analysis of the scientific and technological aspects in module A. Recommendations for communication and actions to be taken for the future positioning of P and T have been developed. In the project part, coordinated by HZDR - status of R and D - an overview on the whole topic P and T is given. The topic is opened by a short description of reactor systems possible for transmutation. In the following the R and D status of separation technologies, safety technology, accelerator technology, liquid metal technology, spallation target development, transmutation fuel and structural material development, as well as waste conditioning is described. The topic is completed by the specifics of transmutation systems, the basic physics and core designs, the reactor physics, the simulation tools and the development of Safety Approaches. Additionally, the status of existing irradiation facilities with fast neutron spectrum is described. Based on the current R and D status, the research and technology gaps in the topics: separation and conditioning, accelerator and spallation target, and reactor

Annual report 2011. Institute of Ion Beam Physics and Materials Research

Energy Technology Data Exchange (ETDEWEB)

Cordeiro, A.L.; Fassbender, J.; Heera, V.; Helm, M. (eds.)

2012-08-22

The first year of membership of the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) in the Helmholtz Association of German Research Centers (HGF) was a year of many changes also for the Institute of Ion Beam Physics and Materials Research (IIM). The transition period, however, is not yet over, since the full integration of the Center into the HGF will only be completed in the next period of the so-called program-oriented funding (POF). This funding scheme addresses the six core research fields identified by the Helmholtz Association (Energy; Earth and Environment; Health; Key Technologies; Structure of Matter; Aeronautics, Space and Transport) to deal with the grand challenges faced by society, science and industry. Since the Institute has strong contributions to both core fields ''Key Technologies'' and ''Structure of Matter'', intense discussions were held amongst the leading scientists of the Institute, across the Institutes of the HZDR, and finally with leading scientists of other Helmholtz centers, to determine the most appropriate classification of the Institute's research. At the end we decided to establish ourselves in Structure of Matter, the core field in which most of the large-scale photon, neutron and ion facilities in Germany are located. As a consequence, the Ion Beam Center (IBC) of the Institute submitted an application to become a HGF recognized large-scale facility, providing more than 50% of its available beam time to external users. This application perfectly reflects the development of the IBC over more than a decade as a European Union funded infrastructure in the framework of the projects ''Center for Application of Ion Beams in Materials Research (AIM)'' (1998-2000, 2000-2003, 2006-2010) and subsequently as the coordinator of the integrated infrastructure initiative (I3) ''Support of Public and Industrial Research using Ion Beam Technology (SPIRIT)'' (2009

Nuclear safety research in HGF 2012; Fortschrittsbericht 2012. Programm 'Nukleare Sicherheitsforschung' Helmholtz-Gemeinschaft

Energy Technology Data Exchange (ETDEWEB)

Anon.

2013-06-15

in the Nuclear Competence Association. The Forschungszentrum Juelich GmbH, HZDR Helmholtz-Zentrum Dresden-Rossendorf and the KIT Karlsruhe Institute of Technology are involved in the Nuclear Safety Research Program within the Helmholtz Association. The work and results in 2012 are presented. (orig.)

Simulation of water hammer experiments using RELAP5 code

International Nuclear Information System (INIS)

Kaliatka, A.; Vaisnoras, M.

2005-01-01

The rapid closing or opening of a valve causes pressure transients in pipelines. The fast deceleration of the liquid results in high pressure surges upstream the valve, thus the kinetic energy is transformed into the potential energy, which leads to the temporary pressure increases. This phenomenon is called water hammer. The intensity of water hammer effects will depend upon the rate of change in the velocity or momentum. Generally water hammer can occur in any thermal-hydraulic systems and it is extremely dangerous for the thermal-hydraulic system since, if the pressure induced exceeds the pressure range of a pipe given by the manufacturer, it can lead to the failure of the pipeline integrity. Due to its potential for damage of pipes, water hammer has been a subject of study since the middle of the nineteenth century. Many theoretical and experimental investigations were performed. The experimental investigation of the water hammer tests performed at Fraunhofer Institute for Environmental, Safety and Energy Technology (UMSICHT) [1] and Cold Water Hammer experiment performed by Forschungszentrum Rossendorf (CWHTF) [2] should be mentioned. The UMSICHT facility in Oberhausen was modified in order to simulate a piping system and associated supports that are typical for a nuclear power plant [3]. The Cold water hammer experiment is interesting and instructive because it covers a wide spectrum of particularities. One of them is sub-cooled water interaction with condensing steam at the closed end of the vertical pipe at room temperature and corresponding saturation pressure [4]. In the paper, the capabilities of RELAP5 code to correctly represent the water hammer phenomenon are presented. Paper presents the comparison of RELAP5 calculated and measured at UMSICHT and CWHTF test facilities pressure transient values after the fast closure (opening) of valves. The analyses of rarefaction wave travels inside the pipe and condensation of vapour bubbles in the liquid column

Infrared studies of impurity states and ultrafast carrier dynamics in semiconductor quantum structures

Energy Technology Data Exchange (ETDEWEB)

Stehr, D.

2007-12-28

This thesis deals with infrared studies of impurity states, ultrafast carrier dynamics as well as coherent intersubband polarizations in semiconductor quantum structures such as quantum wells and superlattices, based on the GaAs/AlGaAs material system. In the first part it is shown that the 2p{sub z} confined impurity state of a semiconductor quantum well develops into an excited impurity band in the case of a superlattice. This is studied by following theoretically the transition from a single to a multiple quantum well or superlattice by exactly diagonalizing the three-dimensional Hamiltonian for a quantum well system with random impurities. These results also require reinterpretation of previous experimental data. The relaxation dynamics of interminiband transitions in doped GaAs/AlGaAs superlattices in the mid-IR are studied. This involves single-color pump-probe measurements to explore the dynamics at different wavelengths, which is performed with the Rossendorf freeelectron laser (FEL), providing picosecond pulses in a range from 3-200 {mu}m and are used for the first time within this thesis. In these experiments, a fast bleaching of the interminiband transition is observed followed by thermalization and subsequent relaxation, whose time constants are determined to be 1-2 picoseconds. This is followed by an additional component due to carrier cooling in the lower miniband. In the second part, two-color pump-probe measurements are performed, involving the FEL as the pump source and a table-top broad-band tunable THz source for probing the transmission changes. In addition, the dynamics of excited electrons within the minibands is explored and their contribution quantitatively extracted from the measurements. Intersubband absorption experiments of photoexcited carriers in single quantum well structures, measured directly in the time-domain, i.e. probing coherently the polarization between the first and the second subband, are presented. By varying the carrier

Annual report 2011. Institute of Radiochemistry

International Nuclear Information System (INIS)

Bernhard, G.

2011-01-01

The Institute of Radiochemistry (IRC) IS one of the seven institutes of the Helmholtz- Zentrum Dresden-Rossendorf (HZDR). The research activities are fully integrated into the ''Nuclear Safety Research Program'' of the Helmholtz Association and focused on the topic ''Safety of Nuclear Waste Disposal''. The research objectives are to generate better process understanding and data for the long-term safety analysis of a nuclear waste disposal in the deep geological underground. A better knowledge about the dominating processes essential for radionuclide (actinide) mobilization and immobilization on the molecular level is needed for the assessment of the macroscopic processes which determine the transport and distribution of radioactivity in the environment. Special emphasis is put on the biological mediated transport of long-lived radionuclides in the geosphere and their interaction with different biosystems like biota and human organism for a better calculation of environmental and health risks. Advanced knowledge is needed for description of the processes dominating at the interfaces between geo- and bio-systems related to the distribution of long-lived radionuclides in various bio-systems along the food chain. More than 120 scientists, technicians, and students, working on their Ph.D., diploma, master, or bachelor thesis, were employed at the Institute of Radiochemistry in 2011. About 20 Ph.D. students are working at the institute. Promotion of young scientists is an important requirement to ensure the competence and further excellent scientific results in the discipline of radiochemistry in future times. We accomplished many new scientific results in the past year, which are presented in this Annual Report, and about 50 original papers were published in peer-reviewed international scientific journals. In 2011, the future research profile of the HZDR was under discussion with the aim to focus the research fields and programs. One result of this process was the

Setup and taking into operation of a photoneutron source; Aufbau und Inbetriebnahme einer Photoneutronenquelle

Energy Technology Data Exchange (ETDEWEB)

Greschner, Martin

2013-07-01

The Institute for Nuclear and Particle Physics at the Technische Universitaet Dresden (TUD) has build a neutron physics laboratory at Forschungszentrum Dresden-Rossendorf (FZD) to investigate nuclear processes in materials. The experiments are focused on materials relevant to nuclear fusion. The laboratory is equipped with three intensive neutron sources. The first is a 14 MeV monochromatic neutron source based on the DT reaction (owned by TUD); the other two are continuous and pulsed white photoneutron sources based on (γ,xn) reactions. One pulsed photoneutron source is realized by FZD in cooperation with the TUD. The continuous photoneutron source utilises a tungsten radiator (Tungsten Photoneutron Source) to produce neutrons with a wide energy spectra. The TPNS uses the ELBE-accelerator as a source of electrons for neutron production. This process involves an intermediate step, where slowed down electrons produce bremsstrahlung (γ-rays) absorbed by tungsten nuclei. Consecutively, the excited nuclei emit neutrons. The neutron flux of the photoneutron source is five orders of magnitude higher than the flux of the DT neutron sources with appropriate moderation. The neutron spectrum of TPNS can be modified by moderators, in such a way that the spectrum is comparable to that in the first wall of a Tokamak-Reactor. That allows investigations with the typical neutron spectrum of the fusion reactor. The technical solution, initial operation and the first experiment are described in this work. The neutron source is, in particular, dedicated to quantitative investigations in fusion neutronics. A fusion reactor produces radioactive isotopes as a nuclear waste. The main activity is accumulated in the structural materials. Carefully selected structural materials can significantly minimize the activity and thereby the amount of nuclear waste. The purpose of this project is to find constructional materials with half-lives shorter than several years, which can be recycled

A 3D heat conduction model for block-type high temperature reactors and its implementation into the code DYN3D

International Nuclear Information System (INIS)

Baier, Silvio; Kliem, Soeren; Rohde, Ulrich

2011-01-01

The gas-cooled high temperature reactor is a concept to produce energy at high temperatures with a high level of inherent safety. It gets special attraction due to e.g. high thermal efficiency and the possibility of hydrogen production. In addition to the PBMR (Pebble Bed Modular Reactor) the (V)HTR (Very high temperature reactor) concept has been established. The basic design of a prismatic HTR consists of the following elements. The fuel is coated with four layers of isotropic materials. These so-called TRISO particles are dispersed into compacts which are placed in a graphite block matrix. The graphite matrix additionally contains holes for the coolant gas. A one-dimensional model is sufficient to describe (the radial) heat transfer in LWRs. But temperature gradients in a prismatic HTR can occur in axial as well as in radial direction, since regions with different heat source release and with different coolant temperature heat up are coupled through the graphite matrix elements. Furthermore heat transfer into reflector elements is possible. DYN3D is a code system for coupled neutron and thermal hydraulics core calculations developed at the Helmholtzzentrum Dresden-Rossendorf. Concerning neutronics DYN3D consists of a two-group and multi-group diffusion approach based on nodal expansion methods. Furthermore a 1D thermal-hydraulics model for parallel coolant flow channels is included. The DYN3D code was extensively verified and validated via numerous numerical and experimental benchmark problems. That includes the NEA CRP benchmarks for PWR and BWR, the Three-Miles-Island-1 main steam line break and the Peach Bottom Turbine Trip benchmarks, as well as measurements carried out in an original-size VVER-1000 mock-up. An overview of the verification and validation activities can be found. Presently a DYN3D-HTR version is under development. It involves a 3D heat conduction model to deal with higher-(than one)-dimensional effects of heat transfer and heat conduction in

Benchmark for Neutronic Analysis of Sodium-cooled Fast Reactor Cores with Various Fuel Types and Core Sizes

International Nuclear Information System (INIS)

Stauff, N.E.; Kim, T.K.; Taiwo, T.A.; Buiron, L.; Rimpault, G.; Brun, E.; Lee, Y.K.; Pataki, I.; Kereszturi, A.; Tota, A.; Parisi, C.; Fridman, E.; Guilliard, N.; Kugo, T.; Sugino, K.; Uematsu, M.M.; Ponomarev, A.; Messaoudi, N.; Lin Tan, R.; Kozlowski, T.; Bernnat, W.; Blanchet, D.; Brun, E.; Buiron, L.; Fridman, E.; Guilliard, N.; Kereszturi, A.; Kim, T.K.; Kozlowski, T.; Kugo, T.; Lee, Y.K.; Lin Tan, R.; Messaoudi, N.; Parisi, C.; Pataki, I.; Ponomarev, A.; Rimpault, G.; Stauff, N.E.; Sugino, K.; Taiwo, T.A.; Tota, A.; Uematsu, M.M.; Monti, S.; Yamaji, A.; Nakahara, Y.; Gulliford, J.

2016-01-01

One of the foremost Generation IV International Forum (GIF) objectives is to design nuclear reactor cores that can passively avoid damage of the reactor when control rods fail to scram in response to postulated accident initiators (e.g. inadvertent reactivity insertion or loss of coolant flow). The analysis of such unprotected transients depends primarily on the physical properties of the fuel and the reactivity feedback coefficients of the core. Within the activities of the Working Party on Scientific Issues of Reactor Systems (WPRS), the Sodium Fast Reactor core Feed-back and Transient response (SFR-FT) Task Force was proposed to evaluate core performance characteristics of several Generation IV Sodium-cooled Fast Reactor (SFR) concepts. A set of four numerical benchmark cases was initially developed with different core sizes and fuel types in order to perform neutronic characterisation, evaluation of the feedback coefficients and transient calculations. Two 'large' SFR core designs were proposed by CEA: those generate 3 600 MW(th) and employ oxide and carbide fuel technologies. Two 'medium' SFR core designs proposed by ANL complete the set. These medium SFR cores generate 1 000 MW(th) and employ oxide and metallic fuel technologies. The present report summarises the results obtained by the WPRS for the neutronic characterisation benchmark exercise proposed. The benchmark definition is detailed in Chapter 2. Eleven institutions contributed to this benchmark: Argonne National Laboratory (ANL), Commissariat a l'energie atomique et aux energies alternatives (CEA of Cadarache), Commissariat a l'energie atomique et aux energies alternatives (CEA of Saclay), Centre for Energy Research (CER-EK), Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Helmholtz Zentrum Dresden Rossendorf (HZDR), Institute of Nuclear Technology and Energy Systems (IKE), Japan Atomic Energy Agency (JAEA), Karlsruhe Institute of Technology (KIT

Nuclear safety research in HGF 2011

International Nuclear Information System (INIS)

Tromm, Walter

2012-01-01

partners in the Nuclear Competence Association. As of January 2011, the Dresden-Rossendorf Helmholtz Center (HZDR), with its 2 Institutes of Safety Research and for Radiochemistry, is an integral part of the Nuclear Safety Research Program within the Energy Research Area. Both institutes work on topics of safety research for nuclear reactors and safety research for nuclear waste management. In this way, the 2 institutes represent very welcome added value as well as a supplement to the Nuclear Safety Research Program. (orig.)

Annual report 2011. Institute of Radiochemistry

Energy Technology Data Exchange (ETDEWEB)

Bernhard, G [ed.

2011-07-01

The Institute of Radiochemistry (IRC) IS one of the seven institutes of the Helmholtz- Zentrum Dresden-Rossendorf (HZDR). The research activities are fully integrated into the ''Nuclear Safety Research Program'' of the Helmholtz Association and focused on the topic ''Safety of Nuclear Waste Disposal''. The research objectives are to generate better process understanding and data for the long-term safety analysis of a nuclear waste disposal in the deep geological underground. A better knowledge about the dominating processes essential for radionuclide (actinide) mobilization and immobilization on the molecular level is needed for the assessment of the macroscopic processes which determine the transport and distribution of radioactivity in the environment. Special emphasis is put on the biological mediated transport of long-lived radionuclides in the geosphere and their interaction with different biosystems like biota and human organism for a better calculation of environmental and health risks. Advanced knowledge is needed for description of the processes dominating at the interfaces between geo- and bio-systems related to the distribution of long-lived radionuclides in various bio-systems along the food chain. More than 120 scientists, technicians, and students, working on their Ph.D., diploma, master, or bachelor thesis, were employed at the Institute of Radiochemistry in 2011. About 20 Ph.D. students are working at the institute. Promotion of young scientists is an important requirement to ensure the competence and further excellent scientific results in the discipline of radiochemistry in future times. We accomplished many new scientific results in the past year, which are presented in this Annual Report, and about 50 original papers were published in peer-reviewed international scientific journals. In 2011, the future research profile of the HZDR was under discussion with the aim to focus the research fields and programs. One result of this process was the

Nuclear safety research in HGF 2011; Nukleare Energieforschung 2011. Forschungszentren. Status und Entwicklung

Energy Technology Data Exchange (ETDEWEB)

Tromm, Walter [Karlsruher Institut fuer Technologie (KIT), Eggenstein-Leopoldshafen (Germany). Programm NUKLEAR

2012-06-15

of the partners in the Nuclear Competence Association. As of January 2011, the Dresden-Rossendorf Helmholtz Center (HZDR), with its 2 Institutes of Safety Research and for Radiochemistry, is an integral part of the Nuclear Safety Research Program within the Energy Research Area. Both institutes work on topics of safety research for nuclear reactors and safety research for nuclear waste management. In this way, the 2 institutes represent very welcome added value as well as a supplement to the Nuclear Safety Research Program. (orig.)

Coolant mixing in pressurized water reactors. Proceedings

International Nuclear Information System (INIS)

Hoehne, T.; Grunwald, G.; Rohde, U.

1998-10-01

models for the numerical solutions require additional experiments. Therefore a 1:5 scaled plexiglas model is under construction at RC Rossendorf. The model can be used variably for PWR's of KONVOI- and EPR-types including the primary loops. The measurements of the mixing effects will be performed with modern wire mesh sensors based on conductivity differences and LDA is used to measure the flow conditions. (orig.)

Rapid data processing for ultrafast X-ray computed tomography using scalable and modular CUDA based pipelines

Science.gov (United States)

Frust, Tobias; Wagner, Michael; Stephan, Jan; Juckeland, Guido; Bieberle, André

2017-10-01

Ultrafast X-ray tomography is an advanced imaging technique for the study of dynamic processes basing on the principles of electron beam scanning. A typical application case for this technique is e.g. the study of multiphase flows, that is, flows of mixtures of substances such as gas-liquidflows in pipelines or chemical reactors. At Helmholtz-Zentrum Dresden-Rossendorf (HZDR) a number of such tomography scanners are operated. Currently, there are two main points limiting their application in some fields. First, after each CT scan sequence the data of the radiation detector must be downloaded from the scanner to a data processing machine. Second, the current data processing is comparably time-consuming compared to the CT scan sequence interval. To enable online observations or use this technique to control actuators in real-time, a modular and scalable data processing tool has been developed, consisting of user-definable stages working independently together in a so called data processing pipeline, that keeps up with the CT scanner's maximal frame rate of up to 8 kHz. The newly developed data processing stages are freely programmable and combinable. In order to achieve the highest processing performance all relevant data processing steps, which are required for a standard slice image reconstruction, were individually implemented in separate stages using Graphics Processing Units (GPUs) and NVIDIA's CUDA programming language. Data processing performance tests on different high-end GPUs (Tesla K20c, GeForce GTX 1080, Tesla P100) showed excellent performance. Program Files doi:http://dx.doi.org/10.17632/65sx747rvm.1 Licensing provisions: LGPLv3 Programming language: C++/CUDA Supplementary material: Test data set, used for the performance analysis. Nature of problem: Ultrafast computed tomography is performed with a scan rate of up to 8 kHz. To obtain cross-sectional images from projection data computer-based image reconstruction algorithms must be applied. The

Redox stability of neptunium(V) in the presence of humic substances of varying functionality

Energy Technology Data Exchange (ETDEWEB)

Schmeide, K.; Geipel, G.; Bernhard, G. [Forschungszentrum Rossendorf e.V., Institute of Radiochemistry, P.O. Box 510 119, D-01314 Dresden (Germany)

2005-07-01

be stabilized in lower oxidation states, e.g. in complexation and sorption studies. [1] Sachs, S., Schmeide, K., Brendler, V., Krepelova, A., Mibus, J., Geipel, G., Heise, K.H., Bernhard, G.: Investigation of the Complexation and the Migration of Actinides and Nonradioactive Substances with Humic Acids under Geo-genic Conditions. Complexation of Humic Acids with Actinides in the Oxidation State IV Th, U, Np. FZR-399, Wissenschaftlich- Technische Berichte, Forschungszentrum Rossendorf, Dresden 2004. [2] Schmeide, K., Geipel, G., Bernhard, G.: Study of the Neptunium(V) Reduction by Various Natural and Synthetic Humic Substances. In: FZKA 7070, Wissenschaftliche Berichte (G. Buckau, ed.). Forschungszentrum Karlsruhe, Karlsruhe 2005, in press. (authors)

Annual report 2011. Institute of Radiochemistry

Energy Technology Data Exchange (ETDEWEB)

Bernhard, G. (ed.)

2011-07-01

The Institute of Radiochemistry (IRC) IS one of the seven institutes of the Helmholtz- Zentrum Dresden-Rossendorf (HZDR). The research activities are fully integrated into the ''Nuclear Safety Research Program'' of the Helmholtz Association and focused on the topic ''Safety of Nuclear Waste Disposal''. The research objectives are to generate better process understanding and data for the long-term safety analysis of a nuclear waste disposal in the deep geological underground. A better knowledge about the dominating processes essential for radionuclide (actinide) mobilization and immobilization on the molecular level is needed for the assessment of the macroscopic processes which determine the transport and distribution of radioactivity in the environment. Special emphasis is put on the biological mediated transport of long-lived radionuclides in the geosphere and their interaction with different biosystems like biota and human organism for a better calculation of environmental and health risks. Advanced knowledge is needed for description of the processes dominating at the interfaces between geo- and bio-systems related to the distribution of long-lived radionuclides in various bio-systems along the food chain. More than 120 scientists, technicians, and students, working on their Ph.D., diploma, master, or bachelor thesis, were employed at the Institute of Radiochemistry in 2011. About 20 Ph.D. students are working at the institute. Promotion of young scientists is an important requirement to ensure the competence and further excellent scientific results in the discipline of radiochemistry in future times. We accomplished many new scientific results in the past year, which are presented in this Annual Report, and about 50 original papers were published in peer-reviewed international scientific journals. In 2011, the future research profile of the HZDR was under discussion with the aim to focus the research fields and programs

Uncertainty analysis of an interfacial area reconstruction algorithm and its application to two group interfacial area transport equation validation

International Nuclear Information System (INIS)

Dave, A.J.; Manera, A.; Beyer, M.; Lucas, D.; Prasser, H.-M.

2016-01-01

Wire mesh sensors (WMS) are state of the art devices that allow high resolution (in space and time) measurement of 2D void fraction distribution over a wide range of two-phase flow regimes, from bubbly to annular. Data using WMS have been recorded at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Lucas et al., 2010; Beyer et al., 2008; Prasser et al., 2003) for a wide combination of superficial gas and liquid velocities, providing an excellent database for advances in two-phase flow modeling. In two-phase flow, the interfacial area plays an integral role in coupling the mass, momentum and energy transport equations of the liquid and gas phase. While current models used in best-estimate thermal-hydraulic codes (e.g. RELAP5, TRACE, TRACG, etc.) are still based on algebraic correlations for the estimation of the interfacial area in different flow regimes, interfacial area transport equations (IATE) have been proposed to predict the dynamic propagation in space and time of interfacial area (Ishii and Hibiki, 2010). IATE models are still under development and the HZDR WMS experimental data provide an excellent basis for the validation and further advance of these models. The current paper is focused on the uncertainty analysis of algorithms used to reconstruct interfacial area densities from the void-fraction voxel data measured using WMS and their application towards validation efforts of two-group IATE models. In previous research efforts, a surface triangularization algorithm has been developed in order to estimate the surface area of individual bubbles recorded with the WMS, and estimate the interfacial area in the given flow condition. In the present paper, synthetically generated bubbles are used to assess the algorithm’s accuracy. As the interfacial area of the synthetic bubbles are defined by user inputs, the error introduced by the algorithm can be quantitatively obtained. The accuracy of interfacial area measurements is characterized for different bubbles

Uncertainty analysis of an interfacial area reconstruction algorithm and its application to two group interfacial area transport equation validation

Energy Technology Data Exchange (ETDEWEB)

Dave, A.J., E-mail: akshayjd@umich.edu [Department of Nuclear Engineering and Rad. Sciences, University of Michigan, Ann Arbor, MI 48105 (United States); Manera, A. [Department of Nuclear Engineering and Rad. Sciences, University of Michigan, Ann Arbor, MI 48105 (United States); Beyer, M.; Lucas, D. [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Fluid Dynamics, 01314 Dresden (Germany); Prasser, H.-M. [Department of Mechanical and Process Engineering, ETH Zurich, 8092 Zurich (Switzerland)

2016-12-15

Wire mesh sensors (WMS) are state of the art devices that allow high resolution (in space and time) measurement of 2D void fraction distribution over a wide range of two-phase flow regimes, from bubbly to annular. Data using WMS have been recorded at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Lucas et al., 2010; Beyer et al., 2008; Prasser et al., 2003) for a wide combination of superficial gas and liquid velocities, providing an excellent database for advances in two-phase flow modeling. In two-phase flow, the interfacial area plays an integral role in coupling the mass, momentum and energy transport equations of the liquid and gas phase. While current models used in best-estimate thermal-hydraulic codes (e.g. RELAP5, TRACE, TRACG, etc.) are still based on algebraic correlations for the estimation of the interfacial area in different flow regimes, interfacial area transport equations (IATE) have been proposed to predict the dynamic propagation in space and time of interfacial area (Ishii and Hibiki, 2010). IATE models are still under development and the HZDR WMS experimental data provide an excellent basis for the validation and further advance of these models. The current paper is focused on the uncertainty analysis of algorithms used to reconstruct interfacial area densities from the void-fraction voxel data measured using WMS and their application towards validation efforts of two-group IATE models. In previous research efforts, a surface triangularization algorithm has been developed in order to estimate the surface area of individual bubbles recorded with the WMS, and estimate the interfacial area in the given flow condition. In the present paper, synthetically generated bubbles are used to assess the algorithm’s accuracy. As the interfacial area of the synthetic bubbles are defined by user inputs, the error introduced by the algorithm can be quantitatively obtained. The accuracy of interfacial area measurements is characterized for different bubbles

Simulation of coolant mixing in pressure vessel reactors

International Nuclear Information System (INIS)

Hoehne, T.

2003-06-01

The work was aimed at the experimental investigation and numerical simulation of coolant mixing in the downcomer and the lower plenum of PWRs. Generally, the coolant mixing is of relevance for two classes of accident scenarios - boron dilution and cold water transients. For the investigation of the relevant mixing phenomena, the Rossendorf test facility ROCOM has been designed. ROCOM is a 1:5 scaled Plexiglas trademark model of the PWR Konvoi allowing conductivity measurements by wire mesh sensors and velocity measurements by the LDA technique. The CFD calculations were carried out with the CFD-code CFX-4. For the design of the facility, calculations were performed to analyze the scaling of the model. It was found, that the scaling of 1:5 to the prototype meets both: physical and economical demands. Flow measurements and the corresponding CFD calculations in the ROCOM downcomer under steady state conditions showed a Re number independency at nominal flow rates. The flow field is dominated by recirculation areas below the inlet nozzles. Transient flow measurements with high performance LDA-technique showed in agreement with CFX-4 results, that in the case of the start up of a pump after a laminar stage large vortices dominate the flow. In the case of stationary mixing, the maximum value of the averaged mixing scalar at the core inlet was found in the sector below the inlet nozzle, where the tracer was injected. At the start-up case of one pump due to a strong impulse driven flow at the inlet nozzle the horizontal part of the flow dominates in the downcomer. The injection is distributed into two main jets, the maximum of the tracer concentration at the core inlet appears at the opposite part of the loop where the tracer was injected. Additionally, the stationary three-dimensional flow distribution in the downcomer and the lower plenum of a VVER-440/V-230 reactor was calculated with CFX-4. The comparison with experimental data and an analytical mixing model showed a

Spectral measurements of runway electrons in the TEXTOR tokamak

International Nuclear Information System (INIS)

Kudyakov, Timur

2009-01-01

The generation of multi-MeV runaway electrons is a well known effect related to the plasma disruptions in tokamaks. The runaway electrons can substantially reduce the lifetime of the future tokamak ITER. In this thesis physical properties of runaway electrons and their possible negative effects on ITER have been studied in the TEXTOR tokamak. A new diagnostic, a scanning probe, has been developed to provide direct measurements of the absolute number of runaway electrons coming from the plasma, its energy distribution and the related energy load in the material during low density (runaway) discharges and during disruptions. The basic elements of the probe are YSO crystals which transform the energy of runaway electrons into visible light which is guided via optical fibres to photomultipliers. In order to obtain the energy distribution of runaways, the crystals are covered with layers of stainless steel (or tungsten in two earlier test versions) of different thicknesses. The final probe design has 9 crystals and can temporally and spectrally resolve electrons with energies between 4 MeV and 30 MeV. The probe is tested and absolutely calibrated at the linear electron accelerator ELBE in Rossendorf. The measurements are in good agreement with Monte Carlo simulations using the Geant4 code. The runaway transport in the presence of the internal and externally applied magnetic perturbations has been studied. The diffusion coefficient and the value of the magnetic fluctuation for runaways were derived as a function of B t . It was found that an increase of runaway losses from the plasma with the decreasing toroidal magnetic field is accompanied with a growth of the magnetic fluctuation in the plasma. The magnetic shielding picture could be confirmed which predicts that the runaway loss occurs predominantly for low energy runaways (few MeV) and considerably less for the high energy ones. In the case of the externally applied magnetic perturbations by means of the dynamic

Comparative EXAFS study of uranium(VI) and neptunium(V) sorption onto kaolinite

International Nuclear Information System (INIS)

Reich, T.; Amayri, S.; Reich, Ta.; Jermolajev, J.

2005-01-01

Full text of publication follows: We investigated the surface sorption process of U(VI) and Np(V) on kaolinite by extended X-ray absorption fine structure (EXAFS) spectroscopy in the 10 μM concentration range. Batch experiments with kaolinite in CO 2 -equilibrated systems showed that the adsorption edge of U(VI) occurs at pH 5.5, i.e., near the pH PZC of kaolinite. The adsorption edge of Np(V) occurs well above the pH PZC value at pH 8.5. This may indicate that the bonds between Np(V) and the surface functional groups of kaolinite are not as strong as in the case of U(VI). U(VI) and Np(V) have in common that the amount which is adsorbed decreases when the pH is increased beyond the absorption maximum. This behavior can be attributed to the formation of U(VI) and Np(V) carbonato complexes in the aqueous solutions. The aim of this comparative EXAFS study was to investigate the reason for the different affinities of U(VI) and Np(V) for kaolinite by measuring their local environments at the clay surface. Samples were prepared from 4 g/L kaolinite, 0.1 M NaClO 4 , pH 3.0 - 10.5, presence and absence of ambient CO 2 . The U L 3 - and Np L 2 -edge EXAFS spectra of the wet paste samples were measured at room temperature in fluorescence mode at the Rossendorf Beamline (ROBL) at the European Synchrotron Radiation Facility. The measured U-O and U-Al/Si distances indicate inner-sphere sorption of U(VI) on kaolinite. There was no evidence of uranium neighbors in the EXAFS spectra, suggesting that the adsorbed U(VI) complexes were predominantly monomeric. The average distance between uranium and its equatorial oxygen atoms, O eq , increased from 2.32 to 2.38 Angstrom in the presence of atmospheric CO 2 when the pH was increased from 5.0 to 8.5. In the CO 2 -free system, the U-O eq distance was independent from pH and equal to 2.32 Angstrom. The lengthening of the average U-O eq distance in the presence of carbonate (or bicarbonate) suggests the formation of ternary U

Advanced techniques in actinide spectroscopy (ATAS 2014). Abstract book

International Nuclear Information System (INIS)

Foerstendorf, Harald; Mueller, Katharina; Steudtner, Robin

2014-01-01

In 2012, The Institute of Resource Ecology at the Helmholtz-Zentrum Dresden Rossendorf organized the first international workshop of Advanced Techniques in Actinide Spectroscopy (ATAS). A very positive feedback and the wish for a continuation of the workshop were communicated from several participants to the scientific committee during the workshop and beyond. Today, the ATAS workshop has been obviously established as an international forum for the exchange of progress and new experiences on advanced spectroscopic techniques for international actinide and lanthanide research. In comparison to already established workshops and conferences on the field of radioecology, one main focus of ATAS is to generate synergistic effects and to improve the scientific discussion between spectroscopic experimentalists and theoreticians. The exchange of ideas in particular between experimental and theoretical applications in spectroscopy and the presentation of new analytical techniques are of special interest for many research institutions working on the improvement of transport models of toxic elements in the environment and the food chain as well as on reprocessing technologies of nuclear and non-nuclear waste. Spectroscopic studies in combination with theoretical modelling comprise the exploration of molecular mechanisms of complexation processes in aqueous or organic phases and of sorption reactions of the contaminants on mineral surfaces to obtain better process understanding on a molecular level. As a consequence, predictions of contaminant's migration behaviour will become more reliable and precise. This can improve the monitoring and removal of hazardous elements from the environment and hence, will assist strategies for remediation technologies and risk assessment. Particular emphasis is placed on the results of the first inter-laboratory Round-Robin test on actinide spectroscopy (RRT). The main goal of RRT is the comprehensive molecular analysis of the actinide complex

The application of iterative transformation factor analysis to resolve multi-component EXAFS spectra of uranium(6) complexes with acetic acid as a function of pH

International Nuclear Information System (INIS)

Robberg, A.; Reich, T.

2002-01-01

Synchrotron-based EXAFS spectroscopy is a powerful technique to obtain structural information on radionuclide complexes in solution. Depending on the chemical conditions of the samples several radionuclide species can coexist in the solution as is often the case for environmentally related samples. All radionuclide species, which may have different near-neighbour environments, contribute to the measured EXAFS signal. In order to isolate the EXAFS spectra of the individual species (pure spectral components), it is necessary, in a first step, to measure a series of samples where their composition is changed by variation of one physico-chemical parameter (e.g. pH, concentration, etc.). For the spectral decomposition it is necessary that the EXAFS signal change as a function of the chosen physico-chemical parameter. In a second step, the series of EXAFS spectra is analysed with Eigen analysis and Iterative Transformation Factor Analysis (ITFA). As a result of the ITFA one obtains: a) for each sample the relative concentration of the structural distinguishable species and b) their corresponding pure spectral components. From the information obtained in a), one can construct a speciation diagram. The pure spectral components contain the structural information of the individual species, which can be extracted by conventional EXAFS analysis. To evaluate our ITFA algorithm for EXAFS analysis of mixtures, we prepared a series of eight solution samples of 0.05 M uranium(VI) and 1 M acetate (Ac) in the pH range of 0.1 to 4.5. From thermodynamic constants it is known that under these conditions up to four species can occur: uranyl hydrate, and the 1:1, 1:2 and 1:3 complexes of uranyl acetate. The uranium L III -edge EXAFS spectra were measured at room temperature in transmission mode at the Rossendorf Beamline (ROBL) at the ESRF. The average bond length between uranium and the equatorial oxygen atoms (O eq ) increases from 2.40 to 2.46 angstrom with increasing pH. This increase

Advanced techniques in actinide spectroscopy (ATAS 2014). Abstract book

Energy Technology Data Exchange (ETDEWEB)

Foerstendorf, Harald; Mueller, Katharina; Steudtner, Robin (eds.)

2014-07-01

In 2012, The Institute of Resource Ecology at the Helmholtz-Zentrum Dresden Rossendorf organized the first international workshop of Advanced Techniques in Actinide Spectroscopy (ATAS). A very positive feedback and the wish for a continuation of the workshop were communicated from several participants to the scientific committee during the workshop and beyond. Today, the ATAS workshop has been obviously established as an international forum for the exchange of progress and new experiences on advanced spectroscopic techniques for international actinide and lanthanide research. In comparison to already established workshops and conferences on the field of radioecology, one main focus of ATAS is to generate synergistic effects and to improve the scientific discussion between spectroscopic experimentalists and theoreticians. The exchange of ideas in particular between experimental and theoretical applications in spectroscopy and the presentation of new analytical techniques are of special interest for many research institutions working on the improvement of transport models of toxic elements in the environment and the food chain as well as on reprocessing technologies of nuclear and non-nuclear waste. Spectroscopic studies in combination with theoretical modelling comprise the exploration of molecular mechanisms of complexation processes in aqueous or organic phases and of sorption reactions of the contaminants on mineral surfaces to obtain better process understanding on a molecular level. As a consequence, predictions of contaminant's migration behaviour will become more reliable and precise. This can improve the monitoring and removal of hazardous elements from the environment and hence, will assist strategies for remediation technologies and risk assessment. Particular emphasis is placed on the results of the first inter-laboratory Round-Robin test on actinide spectroscopy (RRT). The main goal of RRT is the comprehensive molecular analysis of the actinide

Dry reloading and packaging of spent fuel at TRIGA MARK I reactor of Medical University Hanover (MHH), Germany

International Nuclear Information System (INIS)

Haferkamp, D.

2008-01-01

which is protected against contamination spreading and provided with a conventional driven by a floor conveyor trolley. 4. Mobile Reloading Station placed directly on the shipping cask, containing adapter to each type of shipping cask, shielded sliding plates and provided with a loading plate for positioning of six packs into the shipping cask. 5. Auxiliary systems including: - cask lid lifting device; - video monitoring device for the shipping cask lids and loads; - air film gliders for transport of shipping casks. Finally one concludes: the dry reloading station for spent fuel packaging into the shipping casks has successfully operated for TRIGA MARK I reactor at Medical University Hanover as well as at the VKTA - Research Reactor in Rossendorf, Germany. It is available as a proven technique for the dry reloading of spent fuels into the shipping casks. (author)

Evolution of the structure of a gas-liquid two-phase flow in a large vertical pipe

International Nuclear Information System (INIS)

Horst-Michael Prasser; Matthias Beyer; Helmar Carl; Sabine Gregor; Dirk Lucas; Peter Schuetz; Frank-Peter Weiss

2005-01-01

Full text of publication follows: Experimental results on the evolution of the radial gas fraction profiles, gas velocity profiles and bubble size distributions in a gas-liquid two-phase flow along a large vertical pipe of 194 mm inner diameter are presented. The tests were performed at the TOPFLOW facility in Rossendorf, where two wire-mesh sensors were used to measure sequences of two-dimensional distributions of local instantaneous gas fraction within the complete pipe cross-section with a lateral resolution of 3 mm and a sampling frequency of 2500 Hz. This data is the basis for a fast flow visualization and for the calculation of the mentioned profiles. The gas fraction profiles were obtained by averaging the sequences over time, velocities were measured by cross-correlation of the signals of the two sensors, which were located on a short (63 mm) distance behind each other. The high resolution of the mesh sensors allows to identify regions of connected measuring points in the data array, which are filled with the gas phase. This method was used to obtain the bubble size distributions. In the experiments, the superficial velocities ranged from 0.04 to 8 m/s for the gas phase and from 0.04 to 1.6 m/s for the liquid. In this way, the experiments cover the range from bubbly to churn turbulent flow regimes. The evolution of the flow structure was studied by varying the distance between the gas injection and the sensor position. This distance was changed by the help of a so-called variable gas injection set-up. It consists of 6 gas injection units, each of them equipped with three rings of orifices in the pipe wall for the gas injection. These rings are fed with the gas phase from ring chambers, which can be individually controlled by valves. The middle ring has orifices of 4 mm diameter, while the upper and the lower rings have nozzles of 1 mm diameter. In this way, 18 different inlet lengths and two different gas injection geometries can be chosen. The latter

Iodination of the humic samples from Hupa project

International Nuclear Information System (INIS)

Reiller, P.; Mercier-Bion, F.; Barre, N.; Gimenez, N.; Miserque, F.

2005-01-01

Full text of publication follows: Iodine radioactive isotopes, such as 129 I, are important radionuclides due to their significant impact in geological disposal: in the conditions of natural reducing groundwaters, iodine would essentially be present in the form of highly mobile iodide anion. But in shallow waters the presence of molecular iodine is to be taken into account. The interaction of iodine with natural organic matter in general and with humic substances (HS) in particular, has been the subject of numerous studies. It has been shown that in some cases, organically bound iodine can dominate the speciation either as methyl iodide or bound to humic substances [1, 2]. It is now also clear that this reactivity is closely related to the occurrence of molecular iodine I 2 (aq). The reaction scheme can be viewed as an electrophilic substitution of a hydrogen atom by an iodine atom on a phenolic ring. Nevertheless, in some of the latter studies, the characterization of the final reaction products did not satisfy the authors completely as total separation from I - produced during the iodination could not be achieved. Thus, further studies were led using samples from the CCE HUPA project: natural humic and fulvic extract from Gorleben [3] and synthetic samples obtained from FZ Rossendorf [4]. Dialysis procedures were envisaged to improve the incomplete separation between the colloidal humic matter and the iodide ions either unreacted or produced by the reaction [2]. The iodination of these samples were monitored using UV-Visible spectrophotometry. As in previous studies [2], the kinetics could not be linearized in simple order but the trends were conform to simple phenolic patterns. The apparent rates could nevertheless be correlated to the aromaticity (H/C ratio) of the samples. After dialysis, the iodine humic/fulvic interaction was characterised to occur as a carbon-iodine covalent bonding by X-ray photoelectron spectroscopy (XPS) [5]. Electro-spray ionisation

Spectral measurements of runway electrons in the TEXTOR tokamak

Energy Technology Data Exchange (ETDEWEB)

Kudyakov, Timur

2009-07-22

The generation of multi-MeV runaway electrons is a well known effect related to the plasma disruptions in tokamaks. The runaway electrons can substantially reduce the lifetime of the future tokamak ITER. In this thesis physical properties of runaway electrons and their possible negative effects on ITER have been studied in the TEXTOR tokamak. A new diagnostic, a scanning probe, has been developed to provide direct measurements of the absolute number of runaway electrons coming from the plasma, its energy distribution and the related energy load in the material during low density (runaway) discharges and during disruptions. The basic elements of the probe are YSO crystals which transform the energy of runaway electrons into visible light which is guided via optical fibres to photomultipliers. In order to obtain the energy distribution of runaways, the crystals are covered with layers of stainless steel (or tungsten in two earlier test versions) of different thicknesses. The final probe design has 9 crystals and can temporally and spectrally resolve electrons with energies between 4 MeV and 30 MeV. The probe is tested and absolutely calibrated at the linear electron accelerator ELBE in Rossendorf. The measurements are in good agreement with Monte Carlo simulations using the Geant4 code. The runaway transport in the presence of the internal and externally applied magnetic perturbations has been studied. The diffusion coefficient and the value of the magnetic fluctuation for runaways were derived as a function of B{sub t}. It was found that an increase of runaway losses from the plasma with the decreasing toroidal magnetic field is accompanied with a growth of the magnetic fluctuation in the plasma. The magnetic shielding picture could be confirmed which predicts that the runaway loss occurs predominantly for low energy runaways (few MeV) and considerably less for the high energy ones. In the case of the externally applied magnetic perturbations by means of the dynamic

Fluid dynamics of bubbly flows

International Nuclear Information System (INIS)

Ziegenhein, Thomas

2016-01-01

Bubbly flows can be found in many applications in chemical, biological and power engineering. Reliable simulation tools of such flows that allow the design of new processes and optimization of existing one are therefore highly desirable. CFD-simulations applying the multi-fluid approach are very promising to provide such a design tool for complete facilities. In the multi-fluid approach, however, closure models have to be formulated to model the interaction between the continuous and dispersed phase. Due to the complex nature of bubbly flows, different phenomena have to be taken into account and for every phenomenon different closure models exist. Therefore, reliable predictions of unknown bubbly flows are not yet possible with the multi-fluid approach. A strategy to overcome this problem is to define a baseline model in which the closure models including the model constants are fixed so that the limitations of the modeling can be evaluated by validating it on different experiments. Afterwards, the shortcomings are identified so that the baseline model can be stepwise improved without losing the validity for the already validated cases. This development of a baseline model is done in the present work by validating the baseline model developed at the Helmholtz-Zentrum Dresden-Rossendorf mainly basing on experimental data for bubbly pipe flows to bubble columns, bubble plumes and air-lift reactors that are relevant in chemical and biological engineering applications. In the present work, a large variety of such setups is used for validation. The buoyancy driven bubbly flows showed thereby a transient behavior on the scale of the facility. Since such large scales are characterized by the geometry of the facility, turbulence models cannot describe them. Therefore, the transient simulation of bubbly flows with two equation models based on the unsteady Reynolds-averaged Navier-Stokes equations is investigated. In combination with the before mentioned baseline model these

Experimental investigations on bubble turbulent diffusion in a vertical large diameter pipe by means of wire-mesh sensors and correlation techniques

International Nuclear Information System (INIS)

Annalisa Manera; Horst-Michael Prasser; Dirk Lucas

2005-01-01

Full text of publication follows: A large number of experiments for water-air vertical flows in a large-diameter pipe has been carried out at the TOPFLOW facility (Forschunszentrum Rossendorf). The experiments cover a wide range of liquid and superficial gas velocity. The test section consists of a vertical pipe of ∼194 mm and 8.5 m long. At a distance of 7.6 m from the air injection, two wire-mesh sensors are installed. The two sensors are mounted at a distance of 63.3 mm from each other. The wire-mesh sensors measure sequences of instantaneous two-dimensional gas-fraction distributions in the cross-section in which they are mounted with a spatial resolution of 3 mm and a frequency of 2500 Hz. The total dimension of the matrix of measuring points for each mesh sensor is 64 x 64. In a central region of the measuring plane, where the void-fraction gradients are small, points of the first wire-mesh sensor are individually cross-correlated in time domain with measuring points belonging to the second wire-mesh sensor. The cross-correlation functions were calculated for pairs of points that are located accurately above each other as well as for points with a lateral distance. The lateral distance was varied from 0 to 48 mm (16 points), which is still within 50% of the pipe radius, i.e. in the region of small void-fraction gradients. The maximum of each of the 17 correlations is selected in order to derive a spatial correlation in the radial direction. The obtained spatial cross-correlations shows a maximum at zero lateral distance and decrease with growing lateral shift. In a region without gradients, the lateral displacement of bubbles is dominated by turbulent diffusion. This gives the opportunity to derive bubble turbulent diffusion coefficients from the spreading of the spatial correlations. At this aim, the spatial correlations have been first corrected to take into account the finite spatial resolution of the sensor and the finite dimension of the bubbles. The

Development of two-phase flow along a large vertical pipe

International Nuclear Information System (INIS)

Dirk Lucas; Prasser, H.M.

2005-01-01

Full text of publication follows: To qualify CFD codes for two-phase flow simulations, closure laws describing the interaction between the phases are needed. Vertical pipe flow is a suitable object for studying the corresponding phenomena in case of dispersed bubbly flow. Here, the bubbles move under clear boundary conditions, resulting in a shear field of nearly constant structure where the bubbles rise for a comparatively long time. This allows to study the lateral motion of the bubbles in a shear flow as well as bubble coalescence and break-up by comparing gas volume fraction distributions and bubble size distributions at different heights. Very detailed data were obtained at the TOPFLOW facility of the Forschungszentrum Rossendorf using an advanced wire-mesh sensor. This sensor measures the instantaneous conductivity distribution over the pipe cross section. The high frequency of the measurement (2500 frames/s) allows the detection of single bubbles by a special evaluation procedure. Bubble size distributions, gas volume fraction distributions and also gas fraction distributions decomposed according to the bubble size are delivered as result of the evaluation procedure. The use of two sensors allows to measure the profile of the gas velocity. In previous works similar data for pipe of 51.2 mm inner diameter were used for the validation of non-drag bubble forces [1] and the evaluation of the influence of radial profiles on the development of the flow pattern [2]. First investigations on scaling effects were done using data obtained at a pipe with an inner diameter of 194 mm [3]. A constant distance between gas injection and measuring plane of L/D ∼ 40 was used. From a new test series now measurements are available for varying distances between the injection device and the wire-mesh sensor. This allows the evaluation of the development of the flow along the pipe. The data are used for the development and validation of mesoscale models for the forces acting on

Fluid dynamics of bubbly flows

Energy Technology Data Exchange (ETDEWEB)

Ziegenhein, Thomas

2016-07-08

Bubbly flows can be found in many applications in chemical, biological and power engineering. Reliable simulation tools of such flows that allow the design of new processes and optimization of existing one are therefore highly desirable. CFD-simulations applying the multi-fluid approach are very promising to provide such a design tool for complete facilities. In the multi-fluid approach, however, closure models have to be formulated to model the interaction between the continuous and dispersed phase. Due to the complex nature of bubbly flows, different phenomena have to be taken into account and for every phenomenon different closure models exist. Therefore, reliable predictions of unknown bubbly flows are not yet possible with the multi-fluid approach. A strategy to overcome this problem is to define a baseline model in which the closure models including the model constants are fixed so that the limitations of the modeling can be evaluated by validating it on different experiments. Afterwards, the shortcomings are identified so that the baseline model can be stepwise improved without losing the validity for the already validated cases. This development of a baseline model is done in the present work by validating the baseline model developed at the Helmholtz-Zentrum Dresden-Rossendorf mainly basing on experimental data for bubbly pipe flows to bubble columns, bubble plumes and air-lift reactors that are relevant in chemical and biological engineering applications. In the present work, a large variety of such setups is used for validation. The buoyancy driven bubbly flows showed thereby a transient behavior on the scale of the facility. Since such large scales are characterized by the geometry of the facility, turbulence models cannot describe them. Therefore, the transient simulation of bubbly flows with two equation models based on the unsteady Reynolds-averaged Navier-Stokes equations is investigated. In combination with the before mentioned baseline model these

Department of Detectors and Nuclear Electronics: Overview

International Nuclear Information System (INIS)

Guzik, Z.

2003-01-01

Full text: The basic activities of the Department of Nuclear Electronics were concentrated on the following areas: - studies of new scintillation techniques, - contribution to the big European projects, - electronics for experiments in High Energy Physics, - development, investigation and production of silicon detectors, - development of γ-ray spectrometry apparatus, - development of new generation state of the art PCI based multi-channel analysers, - technical support for the Institute as the whole with special emphasis on networking, - normalisation activities. Most of the scientific achievements concerning the Department were summarized in 20 publications (released or being in press). The papers were published mainly in IEEE Trans. on Nucl. Sci. and Nucl. Instr. and Methods. Besides that, our scientists presented 6 contributions at international conferences (such as IEEE Nuclear Science Symposium 2002 in Norfolk, USA). The Department was involved in scientific collaborations with a number of international centers, such as CERN, Royal Institute of Technology in Stockholm, FZR Rossendorf, IKF Juelich, GSI Darmstadt and companies as Advanced Photonix, Inc in California, Scionix in Holland and Photonis in France. The collaboration with High Energy Physics Department of our Institute was focused on LHCb experiment in CERN. In the studies of new scintillation techniques large area avalanche photodiodes were used successfully to tests numerous scintillators at liquid nitrogen temperature. The study of pure (undoped) NaI showed some intriguing effects dealing with non-proportionality of the light yield versus energy of γ-quanta and intrinsic energy resolution of the crystals, which may provide a deeper insight into origin of intrinsic resolution. A very high-energy resolution of 3.8% was measured for 662 keV γ-rays from a 137 Cs source. Moreover, very promising properties of pure NaI at room temperature were shown for the first time. The study of Hamamatsu avalanche

Uncertainty and sensitivity analysis for the modeling of transients with interaction of thermal hydraulics and neutron kinetics

International Nuclear Information System (INIS)

Soeren Kliem; Siegfried Mittag; Siegfried Langenbuch

2005-01-01

Full text of publication follows: The transition from the application of conservative models to the use of best-estimate models raises the question about the uncertainty of the obtained results. This question becomes especially important, if the best-estimate models should be used for safety analyses in the field of nuclear engineering. Different methodologies were developed to assess the uncertainty of the calculation results of computer simulation codes. One of them is the methodology developed by Gesellschaft fuer Anlagenund Reaktorsicherheit (GRS) which uses the statistical code package SUSA. In the past, this methodology was applied to the calculation results of the advanced thermal hydraulic system code ATHLET. In the frame of the recently finished EU FP5 funded research project VALCO, that methodology was extended and successfully applied to different coupled code systems, including the uncertainty analysis for neutronics. These code systems consist of a thermal hydraulic system code and a 3D neutron kinetic core model. One of the code systems applied was ATHLET coupled with the Rossendorf kinetics code DYN3D. Two real transients at NPPs with VVER-type reactors documented within the VALCO project were selected for analyses. One was the load drop of one of two turbines to house load level at the Loviisa-1 NPP (VVER-440), the second was a test with the switching-off of one of two main feed water pumps at the VVER-1000 Balakovo-4 NPP. The current paper is dedicated to the different steps of the use and implementation of the GRS methodology to coupled code systems and to the assessment of the results obtained by the DYN3D/ATHLET code. Based on the relevant physical processes in both transients, lists of possible sources of uncertainties were compiled. They are specific for the two transients. Besides control parameters like control rod movement and thermal hydraulic parameters like secondary side pressure, mass flow rates, pressurizer sprayer and heater

Research coordination meeting of the coordinated research project on analytical and experimental benchmark analyses of accelerator driven systems. Working material

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-07-01

The Technical Meeting hosted at the Belarus National Academy of Sciences in Minsk by the Joint Institute of Power Engineering and Nuclear Research 'SOSNY' from 5-9 December 2005 was the kick-off Research Coordination Meeting (RCM) of the IAEA Coordinated Research Project (CRP) on 'Analytical and Experimental Benchmark Analyses of Accelerator Driven Systems (ADS)'. The CRP had received proposals for research agreements and contracts from scientists representing the following 25 institutions: Centro Atomico Bariloche, SCK CEN Mol, Instituto de Pesquisas Energeticas e Nucleares Sao Paulo, Joint Institute of Power Engineering and Nuclear Research SOSNY Minsk, China Institute of Atomic Energy, CEA Cadarache, CNRS Paris, FZ Rossendorf, FZ Karlsruhe, Budapest University of Technology and Economics, Politecnico di Torino, Japan Atomic Energy Agency, Nuclear Research and Consultancy Group (NRG) Petten, Pakistan Institute of Nuclear Science and Technology, AGH-University of Science and Technology Krakow, Institute of Atomic Energy Otwock/Swierk, ITEP Moscow, MEPHI Moscow, Kurchatov Institute, JINR Dubna, Universidad Politecnica de Madrid, CIEMAT Madrid, Royal Institute of Technology Stockholm, National Science Center 'Kharkov Institute and Technology', and Argonne National Laboratory). These institutions represent 18 IAEA Member States (i.e., Argentina, Belarus, Belgium, Brazil, China, France, Germany, Hungary, Italy, Japan, Netherlands, Pakistan, Poland, Russia, Spain, Sweden, Ukraine, USA), and one International Organization (JINR Dubna). The overall objective of the CRP is contributing to the generic R and D efforts in various fields common to innovative fast neutron system development, i.e., heavy liquid metal thermal hydraulics, dedicated transmutation fuels and associated core designs, theoretical nuclear reaction models, measurement and evaluation of nuclear data for transmutation, and development and validation of calculational methods and codes. Ultimately, the CRP

Realization of radiobiological in vitro cell experiments at conventional X-ray tubes and unconventional radiation sources

International Nuclear Information System (INIS)

Beyreuther, Elke

2010-01-01

More than hundred years after the discovery of X-rays different kinds of ionizing radiation are ubiquitous in medicine, applied to clinical diagnostics and cancer treatment as well. Irrespective of their nature, the widespread application of radiation implies its precise dosimetric characterization and detailed knowledge of the radiobiological effects induced in cancerous and normal tissue. Starting with in vitro cell irradiation experiments, which define basic parameters for the subsequent tissue and animal studies, the whole multi-stage process is completed by clinical trials that translate the results of fundamental research into clinical application. In this context, the present dissertation focuses on the establishment of radiobiological in vitro cell experiments at unconventional, but clinical relevant radiation qualities. In the first part of the present work the energy dependent biological effectiveness of photons was studied examining low-energy X-rays (≤ 50 keV), as used for mammography, and high-energy photons (≥ 20 MeV) as proposed for future radiotherapy. Cell irradiation experiments have been performed at conventional X-ray tubes providing low-energy photons and 200 kV reference radiation as well. In parallel, unconventional quasi-monochromatic channeling X-rays and high-energy bremsstrahlung available at the radiation source ELBE of the Forschungszentrum Dresden-Rossendorf were considered for radiobiological experimentation. For their precise dosimetric characterization dosimeters based on the thermally stimulated emission of exoelectrons and on radiochromic films were evaluated, whereas just the latter was found to be suitable for the determination of absolute doses and spatial dose distributions at cell position. Standard ionization chambers were deployed for the online control of cell irradiation experiments. Radiobiological effects were analyzed in human mammary epithelial cells on different subcellular levels revealing an increasing amount

Realization of radiobiological in vitro cell experiments at conventional X-ray tubes and unconventional radiation sources

Energy Technology Data Exchange (ETDEWEB)

Beyreuther, Elke

2010-09-10

More than hundred years after the discovery of X-rays different kinds of ionizing radiation are ubiquitous in medicine, applied to clinical diagnostics and cancer treatment as well. Irrespective of their nature, the widespread application of radiation implies its precise dosimetric characterization and detailed knowledge of the radiobiological effects induced in cancerous and normal tissue. Starting with in vitro cell irradiation experiments, which define basic parameters for the subsequent tissue and animal studies, the whole multi-stage process is completed by clinical trials that translate the results of fundamental research into clinical application. In this context, the present dissertation focuses on the establishment of radiobiological in vitro cell experiments at unconventional, but clinical relevant radiation qualities. In the first part of the present work the energy dependent biological effectiveness of photons was studied examining low-energy X-rays (≤ 50 keV), as used for mammography, and high-energy photons (≥ 20 MeV) as proposed for future radiotherapy. Cell irradiation experiments have been performed at conventional X-ray tubes providing low-energy photons and 200 kV reference radiation as well. In parallel, unconventional quasi-monochromatic channeling X-rays and high-energy bremsstrahlung available at the radiation source ELBE of the Forschungszentrum Dresden-Rossendorf were considered for radiobiological experimentation. For their precise dosimetric characterization dosimeters based on the thermally stimulated emission of exoelectrons and on radiochromic films were evaluated, whereas just the latter was found to be suitable for the determination of absolute doses and spatial dose distributions at cell position. Standard ionization chambers were deployed for the online control of cell irradiation experiments. Radiobiological effects were analyzed in human mammary epithelial cells on different subcellular levels revealing an increasing amount

Studies on Romanian archaeological objects using nuclear methods: cases of Pietroasa hoard and Cucuteni ceramics

International Nuclear Information System (INIS)

Constantinescu, B.; Cojocaru, V.; Bugoi, R.; Dumitriu, D.E.; Grambole, D.; Herrmann, F.; Secleman, D.; Popovici, M.

2003-01-01

The study of trace-elements in archaeological metallic objects can provide important clues about the metal provenance and the involved manufacturing procedures, leading to important conclusions regarding the commercial, cultural and religious exchanges between the antique populations. Ancient metallic materials are usually inhomogeneous on a scale of 20 microns or less: they contain remains of imperfect smelting, segregated phases in alloys, inclusions. Due to their exceptional chemical stability, gold artifacts remain essentially unchanged during weathering and aging processes. Several fragments of ancient gold objects coming from an Eneolithic treasury and from Pietroasa 'Closca cu Puii de Aur' ('The Golden Brood Hen with Its Chickens') hoard, unearthed on Romanian territory and two Romanian native gold nuggets samples were analyzed using micro-PIXE technique at the Rossendorf TANDETRON microbeam facility. The purpose of the study was to clarify the metal provenance, establishing if the hypothesis of local gold holds. To reach this goal, trace elements (Cu, Te, Sn, Pb, Hg, As, Zr, Sb) and PGE (Platinum Group Elements) concentrations were determined. The presence of inclusions (micrometric size areas of composition different from the surroundings) was also checked. We found some Si, Ca, Fe ones on two Eneolithic samples, and a Ta-Cr one on a sample from Pietroasa hoard. The measurements led to conclusions regarding the alluvial origin of the gold for the Eneolithic samples and gave some indications for the possible gold ore sources of Pietroasa treasury - Urals mountains and north-eastern Turkey, confirming the heterogeneity of this treasury (the two analyzed pieces belonged to different stylistic and compositional groups). Synchrotron Radiation X-Ray Powder Diffraction was used at MAXLAB synchrotron (Lund, Sweden) to distinguish different clays and mineral pigments of various neolithic pottery-producing centres on Romanian territory. As main results we can be

Department of Detectors and Nuclear Electronics - Overview

International Nuclear Information System (INIS)

Guzik, Z.

2006-01-01

I(Tl) crystal as the gamma detector for the EURITRACK project at the borders. Finally, in the third project, guided by the High Energy Physics Department, we contribute to development of the recoil detector for COMPASS experiment at CERN working together with Photonis Company in France on a developing of new large diameter photomultipliers with enhanced timing capabilities. The Department was involved in scientific collaborations with a number of international centers, such as CERN, Royal Institute of Technology and Karolinska Institute in Stockholm, FZR Rossendorf, IKF Juelich, GSI Darmstadt, INFN Padova, CEA Saclay and Cadarache, IRB Zagreb, and companies as Saint-Gobain, Scionix in Holland, Photonis in France, Target in Germany and Siemens (former CTI) in USA. Additionally collaboration with IAEA in Vienna concerning monitoring of State borders was continued. Several scientific contracts were realized for the European industry. The collaboration with High Energy Physics Department of our Institute was focused on LHCb experiment in CERN. Our contribution was to design basic hardware modules concerning overall control of the experiment apparatus. In 2005 the final versions of all of those modules were released and mass production was started. In total there will be used 28 of Readout Supervisors (ODIN), 4 TFC Switches (THOR), 6 Throttle Switches (MUNIN) and 48 Throttle OR's (HUGIN). Our works on development of new generation State of the Art PCI based and USB based multi-channel analysers is very promising. Our USB based device in the form of autonomous miniature screened box was refined and finalized. More than 20 copies of it were sold all around the world. New project concerning new features of the device (Ethernet and wireless interfacing) is under investigation. In the field of semiconductor detectors, besides continuation of previous works, activities concentrated on ion implantation (using TITAN implanter) for production of new type semiconductor radiation detectors

Department of Detectors and Nuclear Electronics - Overview

International Nuclear Information System (INIS)

Guzik, Z.

2007-01-01

the contract with Photonnis, France the contribution to the development of new photomultipliers for gamma spectrometry with LaBr 3 crystals and new fast photomultipliers for time-of-flight PET were carried out. A detector array assembly with lead collimators was designed, constructed and delivered to the EURITRACK project. The EURITRACK system has passed most of the tests in CAE Saclay before its moving to Rijeka harbour in Croatia for blind tests of real containers. The Department was involved in scientific collaborations with a number of international centres, such as CERN, Royal Institute of Technology and Karolinska Institute in Stockholm, FZR Rossendorf, IKF Juelich, GSI Darmstadt, INFN Padova, CEA Saclay and Cadarache, IRB Zagreb, and companies as Saint-Gobain, Scionix in Holland, Photonis in France, ICX (former Target) in Germany, Siemens (former CTI) in USA and Hitachi Chemical, Japan. Additionally collaboration with IAEA in Vienna concerning monitoring of State borders was continued. Several scientific contracts were realized for European industry. The collaboration with the High Energy Physics Department of our Institute was focused on the LHCb experiment in CERN. Our contribution was to design basic hardware modules concerning overall control of the apparatus. In 2006 the designed and produced modules (over 100 in total) were installed in LHCb pit in Meyrin. Also the special module for monitoring LHC beam phase and intensity was proposed and designed. Our work on development of a new generation State of the Art USB based multi-channel analyzers are very promising. Our USB based device in the form of an autonomous miniature screened box was refined and finalized. It sold more than 20 copies all around the world. New project concerning new features of the device (Ethernet and wireless ports) is being designed and debugged. In the field of semiconductor detectors, besides continuation of previous work, activities concentrated on ion implantation (using TITAN

Department of Detectors and Nuclear Electronics - Overview

International Nuclear Information System (INIS)

Guzik, Z.

2008-01-01

carried out. In the studies on homeland security, different measurements carried out with the new LaBr 3 crystals using different photomultipliers and avalanche photodiodes were summarized. Moreover, the BC523A, Boron-10 loaded liquid scintillator was studied for simultaneous detection of fast and thermal neutrons. The EURITRACK project was practically completed by a series of blind tests with real containers at Rijeka, the port of Croatia. The project was a winner of the '' 1 st Prize of Technological Innovation of the French Trophy of Civil Defense 2007 '' awarded by the senate. The Department was involved in scientific collaborations with a number of centers, such as CERN, the Royal Institute of Technology and Karolinska Institute in Stockholm, FZR Rossendorf, IKF Juelich, GSI Darmstadt, INFN Padova, CEA Saclay and Cadarache, IRB Zagreb, and companies as Saint-Gobain, Scionix in Holland, Photonis in France, ICX (former Target) in Germany, Siemens (former CTI) in the USA and Hitachi Chemical, Japan. Additionally collaboration with IAEA in Vienna concerning monitoring of state borders was continued. Several scientific contracts were realized for European industry. The collaboration with the High Energy Physics Department of our Institute was focused on the LHCb experiment in CERN and GSI (Darmstadt). In 2007 the designed and produced modules for the LHCb experiment in CERN was installed and tested in the LHCb pit in Meyrin. Besides that the special module for monitoring the LHC beam phase and intensity was produced and tested on a SPS beam. We also started a collaboration with the PANDA detector in GSI. Our work is focused on the DCS system for the experiment. Our work on the development of new generation State of the Art USB based multi-channel analysers are promising. We sold more the 50 copies of our USB based device all around the world. A new project concerning new features of the device (Ethernet and wireless ports) is being designed and debugged. Also significant

OBITUARY Chris Beling, 1955-2010

Science.gov (United States)

Coleman, P. G.

2011-01-01

deep-level transient spectroscopy [7]. Chris was characteristically interested in all aspects of the research in which he was engaged, and invested much effort in developing theoretical models and data handling [8]. Chris published over 200 journal papers and 75 conference contributions; almost two-thirds of his publications deal with investigations and complex characterisation of semiconductors, mostly combining the results of many different techniques. 15% of his papers were concerned with the building, development and use of a mono-energetic positron beam and other spectroscopies at HKU, and almost 20% involved numerical modelling of experimental data and theoretical studies. A fruitful collaboration involving positron research of semiconductors was promoted by Chris during ICPA-10 in Beijing in 1994, between the HKU positron group and that of Gerhard Brauer at FZ Dresden-Rossendorf. In recent years this has primarily involved Chris's former student Francis Ling, now an associate professor at HKU. Gerhard comments that 'it has always been a great pleasure to meet Chris at Hong Kong for a scientific discussion, or privately with him and members of his family. I shall miss him as a colleague and friend.' Professor Fuchun Zhang, Head of Physics at HKU, writes that, together with Prof. Steve Fung, Chris educated several dozen graduate students, and that his supervision was characterized by his kindness and willingness to help those most in need. The fondness with which Chris was regarded by all who knew him was embodied in the substantial contributions from students, colleagues, friends and family to establish the C.D. Beling Memorial Prize in Physics, which will be awarded annually to three full-time Physics students at HKU. Chris was the son of retired Paignton vicar David Beling and his wife Anne. Chris's brother Jeremy told mourners at St Paul's Church, Paignton: 'When I called for help, he gave not a second thought in helping me. How I wish he had not been on the

THEREDA. Thermodynamic reference database. Summary of final report

Energy Technology Data Exchange (ETDEWEB)

Altmaier, Marcus; Bube, Christiane; Marquardt, Christian [Karlsruher Institut fuer Technologie (KIT), Eggenstein-Leopoldshafen (Germany). Institut fuer Nukleare Entsorgung; Brendler, Vinzenz; Richter, Anke [Helmholtz-Zentrum Dresden-Rossendorf (Germany). Inst. fuer Radiochemie; Moog, Helge C.; Scharge, Tina [Gesellschaft fuer Anlagen- und Reaktorsicherheit mbH (GRS), Koeln (Germany); Voigt, Wolfgang [TU Bergakademie Freiburg (Germany). Inst. fuer Anorganische Chemie; Wilhelm, Stefan [AF-Colenco AG, Baden (Switzerland)

2011-03-15

A long term safety assessment of a repository for radioactive waste requires evidence, that all relevant processes are known and understood, which might have a significant positive or negative impact on its safety. In 2002, a working group of five institutions was established to create a common thermodynamic database for nuclear waste disposal in deep geological formations. The common database was named THEREDA: Thermodynamic Reference Database. The following institutions are members of the working group: Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiochemistry - Karlsruhe Institute of Technology, Institute for Nuclear Waste Disposal - Technische Universitaet Bergakademie Freiberg, Institute of Inorganic Chemistry - AF-Colenco AG, Baden, Switzerland, Department of Groundwater Protection and Waste Disposal - Gesellschaft fur Anlagen- und Reaktorsicherheit, Braunschweig. For the future it is intended that its usage becomes mandatory for geochemical model calculations for nuclear waste disposal in Germany. Furthermore, it was agreed that the new database should be established in accordance with the following guidelines: Long-term usability: The disposal of radioactive waste is a task encompassing decades. The database is projected to operate on a long-term basis. This has influenced the choice of software (which is open source), the documentation and the data structure. THEREDA is adapted to the present-day necessities and computational codes but also leaves many degrees of freedom for varying demands in the future. Easy access: The database is accessible via the World Wide Web for free. Applicability: To promote the usage of the database in a wide community, THEREDA is providing ready-to-use parameter files for the most common codes. These are at present: PHREEQC, EQ3/6, Geochemist's Workbench, and CHEMAPP. Internal consistency: It is distinguished between dependent and independent data. To ensure the required internal consistency of THEREDA, the

THEREDA. Thermodynamic reference database. Summary of final report

International Nuclear Information System (INIS)

Altmaier, Marcus; Bube, Christiane; Marquardt, Christian; Voigt, Wolfgang

2011-03-01

A long term safety assessment of a repository for radioactive waste requires evidence, that all relevant processes are known and understood, which might have a significant positive or negative impact on its safety. In 2002, a working group of five institutions was established to create a common thermodynamic database for nuclear waste disposal in deep geological formations. The common database was named THEREDA: Thermodynamic Reference Database. The following institutions are members of the working group: Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiochemistry - Karlsruhe Institute of Technology, Institute for Nuclear Waste Disposal - Technische Universitaet Bergakademie Freiberg, Institute of Inorganic Chemistry - AF-Colenco AG, Baden, Switzerland, Department of Groundwater Protection and Waste Disposal - Gesellschaft fur Anlagen- und Reaktorsicherheit, Braunschweig. For the future it is intended that its usage becomes mandatory for geochemical model calculations for nuclear waste disposal in Germany. Furthermore, it was agreed that the new database should be established in accordance with the following guidelines: Long-term usability: The disposal of radioactive waste is a task encompassing decades. The database is projected to operate on a long-term basis. This has influenced the choice of software (which is open source), the documentation and the data structure. THEREDA is adapted to the present-day necessities and computational codes but also leaves many degrees of freedom for varying demands in the future. Easy access: The database is accessible via the World Wide Web for free. Applicability: To promote the usage of the database in a wide community, THEREDA is providing ready-to-use parameter files for the most common codes. These are at present: PHREEQC, EQ3/6, Geochemist's Workbench, and CHEMAPP. Internal consistency: It is distinguished between dependent and independent data. To ensure the required internal consistency of THEREDA, the