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Sample records for ujv

  1. Study of radiation damage of steels for light water pressure vessels at UJV

    International Nuclear Information System (INIS)

    Vacek, N.; Stoces, B.

    1980-01-01

    Preoperational determination of radiation resistance of pressure vessel steels is performed at accelerated neutron exposure in a test or materials research reactor. The results obtained at accelerated and operating exposure are not fully identical and surveillance bodies are therefore used manufactured from the pressure vessel material. Currently, the following steels are used for the manufacture of light water reactor pressure vessels: Mn-Mo-Ni (ASTM-A533-B, ASTM-A508), Cr-Mo-V (15Kh2M1FA). At UJV Rez, for irradiation Chanca-M probes imported from France are used featuring electric temperature control. Almost identical radiation embrittlement was measured for all three steels after irradiation with a neutron fluence of 3x10 23 n.m -2 at a temperature of 290 degC. (H.S.)

  2. Decommissioning of evaporation technology for processing liquid radioactive waste in UJV Rez, a. s

    International Nuclear Information System (INIS)

    Tous, M.; Otcovsky, T.; Podlaha, J.

    2015-01-01

    The UJV Rez, a. s. is the main leader in processing institutional radioactive waste (RAW) in the Czech Republic and the Waste Management Department has been established since the research reactor VVR-S (now LVR-15) was put in operation. Due to the large activities in nuclear research and engineering in the past, a big capacity of waste management technologies was needed. The low pressure compactor for volume reduction of solid RAW, as well as chemical pre-treatment technology of liquid RAW were installed and later the evaporation technology for effective processing the liquid RAW with the cementation and bituminization unit for final conditioning of concentrated liquid RAW were used. During the years of research reactor operation and research activities in UJV Rez, a. s. there were two installed evaporation technologies in row. After the latest evaporator lifetime, changes in liquid RAW production and together with higher decontamination factor requirements, this technology was decided to be decommissioned. The decommissioned evaporation technology was installed and put in operation in 1991. This technology was used for processing liquid aqueous RAW produced from internal research activities and of course for external producers and institutions (e.g. universities, medicine, research institutes, industry). The approved decommissioning plan was prepared and the licence for immediate decommissioning was obtained in 2012. Then the decommissioning project started. The preparing stages as dosimetric survey, expected material balance and of course initial decontamination activities were performed. Evaporation technology dismantling and processing the arising RAW were done by the internal staff of Waste Management Department. The total volume of produced RAW was 49,5 m 3 of RAW. The secondary liquid RAW (from decontamination) of amount 1,4 m 3 , contaminated sludge of amount 0,5 m 3 , solid RAW (construction steel) of amount 39,1 m 3 , solid compressible RAW (protective

  3. Scientific conference proceedings. Session 3

    International Nuclear Information System (INIS)

    Bartosek, V.

    1985-01-01

    The Radiochemical Technology session met at UJV Rez on June 7, 1985 to hear 13 papers of which 11 were incorporated in INIS. The papers inform of results attained in the field of processing liquid radioactive wastes from nuclear power plants, processing spent nuclear fuel using the fluoride process, of the separation of fission products by dicarbolide extraction, the chemistry of complex uranium compounds, etc. The cooperation of UJV with VUJE and VUCHZ is also dealt with. (E.S.)

  4. Twenty years of the Nuclear Research Institute and its contribution to the development of nuclear power and technology in Czechoslovakia

    International Nuclear Information System (INIS)

    Havel, S.

    1976-01-01

    A survey is presented of the most important results of scientific research efforts of the Nuclear Research Institute (UJV) attained in the 20 years of the Institute's existence. In 1975 the proportion of the individual fields of research was as follows: reactor technology 37%, reactor materials 19%, nuclear fuel processing including waste processing 18%, ionizing radiation applications 16%, others 10%. In the field of reactor technology, orientation is evident to light-water and fast reactors (1975): light-water reactors 40%, fast reactors 44%, heavy-water reactors 16%. The most significant contribution of the Institute to the first Czechoslovak nuclear power plant A-1 in the past period included the construction of the TR-0 heavy-water critical assembly, the choice of suitable uranium alloys and their thermal and mechanical treatment for the A-1 fuel elements, corrosion and mechanical stability study of cladding materials and post-irradiation fuel study performed in the UJV hot chambers. Significant for the development of light-water reactors are mainly the study of water regimes of radiation-exposed circuits, the solution of primary circuit chemical problems, participation in the international research programme of the CMEA countries related to the ZR-6 (Budapest) critical assembly, and the study of Zr-based cladding materials. UJV is the main Czechoslovak study centre for the development of a fast reactor and its staff have written a number of programmes for the computation of such a reactor and its fuel cycle. Also available is a suitable experimental facility. The Institute also participates in the research of UO 2 -based ceramic fuel, and in the field of spent fuel and radioactive waste processing in the development of extraction processes and the application of fluoride technology. As for ionizing radiation applications, UJV has since 1960 been manufacturing radioactive preparations including, to a limited extent, radiopharmaceuticals. It is envisaged that

  5. Automatic processing of list of journals and publications in the Nuclear Research Institute

    International Nuclear Information System (INIS)

    Vymetal, L.

    Using an EC 1040 computer, the Institute of Nuclear Research processed the list of journals in the reference library of the Czechoslovak Atomic Energy Commission including journals acquired by all institutions subordinated to the Czechoslovak Atomic Energy Commission, ie., UJV Rez (Nuclear Research Institute), Nuclear Information Centre Prague, UVVVR Prague (Institute for Research, Production and Application of Radioisotopes) and Institute of Radioecology and Applied Nuclear Techniques Kosice. Computer processing allowed obtaining files arranged by libraries, subject matters of the journals, countries of publication, and journal titles. Automated processing is being prepared of publications by UJV staff. The preparation is described of data for computer processing of both files and specimens are shown of printouts. (Ha)

  6. Uganda Journal - Vol 48 (2002)

    African Journals Online (AJOL)

    Notes: Observations of Butterfly Migrations in Uganda, 2002 · EMAIL FULL TEXT EMAIL FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Ian Deshmukh, 111-114. http://dx.doi.org/10.4314/uj.v48i1.23007 ...

  7. Journal Home

    African Journals Online (AJOL)

    The Ancient Earthworks of Western Uganda: Capital Sites or a Cwezi Empire · EMAIL FULL TEXT EMAIL FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Peter Robertshaw, 17-32. http://dx.doi.org/10.4314/uj.v48i1.23001 ...

  8. UJV line for research into radioactive wastes solidification

    International Nuclear Information System (INIS)

    Neumann, L.; Feist, I.; Kepak, F.; Nachmilner, L.; Napravnik, J.; Novak, M.; Pecak, V.; Vojtech, O.

    1985-01-01

    An experimental line with a capacity of 0.01 m 3 /h was developed and built for research of the solidification of liquid radioactive wastes at the Nuclear Research Institute. The line allows the research and pilot plant testing of processes based on vitrification but also on other procedures including calcination. It consists of a horizontal calciner, a resistance melting unit, a homogenization device for research into cementation of the calcinate, and equipment for the disposal of gaseous emissions. The facility is provided with a control console which allows remote control and the control of all basic operating parameters. The design of the line allows its eventual completion with other equipment. (Z.M.)

  9. 20 th anniversary of the Nuclear Research Institute (UJV)

    International Nuclear Information System (INIS)

    Havel, S.

    1975-01-01

    The importance of NRI founded twenty years ago, its original mission and tasks in the period of its establishement and the growth of its experimental base made possible by Soviet assistance are shown. A new mission of NRI after its reorganization and its incorporation in the Czechoslovak Atomic Commision is discussed. The survey of main research efforts aimed at the implementation of the programme of the Czechoslovak nuclear power and at meeting the needs of the Czechoslovak national economy is given. (author)

  10. Contributions of the Nuclear Research Institute to the French-Czechoslovak seminar on the management of radioactive wastes held on 12-14 May, 1987

    International Nuclear Information System (INIS)

    1987-01-01

    Paper were submitted on the use of calcination in liquid radioactive waste solidification; experience with the operation of mobile lines of the MESA type which are tested at nuclear power plants; the treatment of low level liquid wastes from special laundries. Other papers described experience with the operation of the facility for processing low and intermediate level wastes run by UJV (Nuclear Research Institute) since 1962, and the conditions for a radioactive waste burial site in Czechoslovakia. (E.S.). 3 tabs

  11. Fires of sodium installations

    International Nuclear Information System (INIS)

    Hajek, L.; Tlalka, R.

    1984-01-01

    A survey is presented of the literature dealing with fires of sodium installations between 1974 and 1981. Also described are three experimental fires of ca 50 kg of sodium in an open area, monitored by UJV Rez. The experimental conditions of the experiments are described and a phenomenological description is presented of the course of the fires. The experiments showed a relationship between wind velocity in the area surrounding the fire and surface temperature of the sodium flame. Systems analysis methods were applied to sodium area, spray and tube fires. (author)

  12. Calculations of spetial and energy distribution of neutrons in reactor core and shielding. Part 1

    International Nuclear Information System (INIS)

    Rataj, J.

    1985-01-01

    The most important methods are briefly described of solving the Boltzmann equation describing neutron transport, such as are used at UJV Rez. These are the methods of P N -approximation, the S N method, further the Monte Carlo method and the moments method in which the solution of the Boltzmann equation describing the spatial and energy distribution of neutron flux density proceeds from the system of equations given by the P N -approximation. It is emphasized that the results are loaded with a big error or are totally erroneous when inaccurate cross sections or unsuitable libraries of cross sections are used. (J.P.)

  13. Automated processing of nuclear materials accounting data

    International Nuclear Information System (INIS)

    Straka, J.; Pacak, P.; Moravec, J.

    1980-01-01

    An automated system was developed of nuclear materials accounting in Czechoslovakia. The system allows automating data processing including data storage. It comprises keeping records of inventories and material balance. In designing the system, the aim of the IAEA was taken into consideration, ie., building a unified information system interconnected with state-run systems of accounting and checking nuclear materials in the signatory countries of the non-proliferation treaty. The nuclear materials accounting programs were written in PL-1 and were tested at an EC 1040 computer at UJV Rez where also the routine data processing takes place. (B.S.)

  14. Remediation of old ecological burdens in UJV Rez, a. s. - alpha hall

    International Nuclear Information System (INIS)

    Posvar, R.; Holubova, D.; Svoboda, K.

    2018-01-01

    Two research reactors, hot and semi-hot chambers, laboratories, radioactive waste disposal facilities and many other technologies are in operation at the Nuclear Power Plant site. As a result of these activities a significant amount of radioactive wastes, contaminated and irradiated materials, equipment and construction structures for disposal and disposal were created in the Nuclear Research Institute. These old radioactive loads can be characterized as ecological liabilities incurred prior to the privatization of the Nuclear Power Plant. The implementation of the rehabilitation works of the Nuclear Power Plant continued and continues to be successful. The results of regular monitoring confirm that there is no release of radioactive substances into the environment. This work focuses on the elimination of the alpha hall workplace in facility 250 - Radiochemistry. The Alpha Hall has been used to research and develop chemical separations and analyzes for uranium and transuranium elements in the fuel cycle chemistry (especially the separation and determination of plutonium, america, neptunium, curium and uranium). In 2015, this workplace was influenced a combination of age degradation with radiation degradation of one of the plastic packages to leakage of the Am and Pu compound. The contamination was local and within the limits of non-interference levels. The health of workers and the environment were not compromised. However, this event has led to an acceleration of the redevelopment of the workplace, which took place between 2016 and 2017. For this purpose, a working procedure was developed which regulates the way of remedial work, including the solidification of the most risky materials. (authors)

  15. Automated nuclear materials accounting

    International Nuclear Information System (INIS)

    Pacak, P.; Moravec, J.

    1982-01-01

    An automated state system of accounting for nuclear materials data was established in Czechoslovakia in 1979. A file was compiled of 12 programs in the PL/1 language. The file is divided into four groups according to logical associations, namely programs for data input and checking, programs for handling the basic data file, programs for report outputs in the form of worksheets and magnetic tape records, and programs for book inventory listing, document inventory handling and materials balance listing. A similar automated system of nuclear fuel inventory for a light water reactor was introduced for internal purposes in the Institute of Nuclear Research (UJV). (H.S.)

  16. General presentation of the EC FP7 SARGEN IV project

    International Nuclear Information System (INIS)

    Blanc, Daniel

    2012-01-01

    SARGEN I V project: Innovative reactors with fast spectrum to be built in Europe. The ESNII roadmap includes: • the ASTRID SFR prototype supported by the French Government; • ALFRED LFR demonstrator; → Romania is interested to host the ALFRED prototype. • the ALLEGRO GFR prototype → A Memorandum of Understanding (MOU) has been signed in May 2010 between UJV (Czech Republic), AEKI (Hungary) and VUJE (Slovakia) to develop ALLEGRO. • the MYRRHA experimental facility supported by the Belgian government is able to: → test the LFR technology; → provide irradiation in the fast spectrum area; → test the Accelerator Driven System (ADS) technology (not retained by the GIF)

  17. Neutron radiography

    International Nuclear Information System (INIS)

    Hrdlicka, Z.

    1977-01-01

    Neutron radiography is a radiographic method using a neutron beam of a defined geometry. The neutron source usually consists of a research reactor, a specialized neutron radiography reactor or the 252 Cf radioisotope source. There are two types of the neutron radiography display system, viz., a system producing neutron radiography images by a photographic process or a system allowing a visual display, eg., using a television monitor. The method can be used wherever X-ray radiography is used except applications in the radiography of humans. The neutron radiography unit at UJV uses the WWR-S reactor as the neutron source and both types of the above mentioned display system. (J.P.)

  18. Radioactive wastes and their disposal

    International Nuclear Information System (INIS)

    Neumann, L.

    1984-01-01

    The classification of radioactive wastes is given and the achievements evaluated in the disposal of radioactive wastes from nuclear power plants. An experimental pilot unit was installed at the Jaslovske Bohunice nuclear power plant for the bituminization of liquid radioactive wastes. UJV has developed a mobile automated high-output unit for cementation. In 1985 the unit will be tested at the Jaslovske Bohunice and the Dukovany nuclear power plants. A prototype press for processing solid wastes was manufactured which is in operation at the Jaslovske Bohunice plant. A solidification process for atypical wastes from long-term storage of spent fuel elements has been developed to be used for the period of nuclear power plant decommissioning. (E.S.)

  19. Radiopharmaceuticals in Czechoslovakia

    International Nuclear Information System (INIS)

    Hron, M.; Kronrad, L.; Svoboda, K.; Melichar, F.

    1986-01-01

    The history is briefly described of the production of radiopharmaceuticals in Czechoslovakia for nuclear medicine purposes. 131 I-labelled orthoiodohippurate and rose Bengal were first produced. Currently, 99m Tc is the most frequently requested radionuclide for radiopharmaceutical labelling. The preparation of 99m Tc is described in detail, a flow chart is shown and the network of 99m Tc distribution to hospitals outlined. In addition of 99m Tc and 131 I, UJV Rez produces other radionuclides for nuclear medicine, such as 113m In, 67 Ga, 35 S, 32 P, 203 Hg, 85 Sr. The methods are being developed of the production of 201 Tl, 125 I and 131 I-labelled bromosulfophthalein. (E.S.)

  20. Reliability analyses of safety systems for WWER-440 nuclear power plants

    International Nuclear Information System (INIS)

    Dusek, J.; Hojny, V.

    1985-01-01

    The UJV in Rez near Prague studied the reliability of the system of emergency core cooling and of the system for suppressing pressure in the sealed area of the nuclear power plant in the occurrence of a loss-of-coolant accident. The reliability of the systems was evaluated by failure tree analysis. Simulation and analytical calculation programs were developed and used for the reliability analysis. The results are briefly presented of the reliability analyses of the passive system for the immediate short-term flooding of the reactor core, of the active low-pressure system of emergency core cooling, the spray system, the bubble-vacuum system and the system of emergency supply of the steam generators. (E.S.)

  1. Neutron and photon spectrometry in mixed radiation fields

    International Nuclear Information System (INIS)

    Jancar, A.; Kopecky, Z.; Veskrna, M.

    2014-01-01

    Spectrometric measurements of the mixed fields of neutron and photon radiation in the workplaces with the L-R-0 research reactor located in the UJV Rez and with the Van de Graaff accelerator, located in the UTEF laboratories Prague, are presented in this paper. The experimental spectrometric measurements were performed using a newly developed digital measuring system, based on the technology of analog-digital converters with a very high sampling frequency (up to 2 GHz), in connection with organic scintillation detector, type BC-501A, and stilbene detector. The results of experimental measurements show high quality of spectrometry mixed fields of neutron and photon radiation across the wide dynamic range of measured energy. (authors)

  2. Qualification of coupled 3D neutron kinetic/thermal hydraulic code systems by the calculation of a VVER-440 benchmark. Re-connection of an isolated loop

    Energy Technology Data Exchange (ETDEWEB)

    Kotsarev, Alexander; Lizorkin, Mikhail [National Research Centre ' Kurchatov Institute' , Moscow (Russian Federation); Bencik, Marek; Hadek, Jan [UJV Rez, a.s., Rez (Czech Republic); Kozmenkov, Yaroslav; Kliem, Soeren [Helmholtz-Zentrum Dresden-Rossendorf (HZDR) e.V., Dresden (Germany)

    2016-09-15

    The 7th AER dynamic benchmark is a continuation of the efforts to validate the codes systematically for the estimation of the transient behavior of VVER type nuclear power plants. The main part of the benchmark is the simulation of the re-connection of an isolated circulation loop with low temperature in a VVER-440 plant. This benchmark was calculated by the National Research Centre ''Kurchatov Institute'' (with the code ATHLET/BIPR-VVER), UJV Rez (with the code RELAP5-3D {sup copyright}) and HZDR (with the code DYN3D/ATHLET). The paper gives an overview of the behavior of the main thermal hydraulic and neutron kinetic parameters in the provided solutions.

  3. Plugging criteria for WWER SG tubes

    Energy Technology Data Exchange (ETDEWEB)

    Papp, L.; Wilam, M. [Vitkovice NPP Services (Switzerland); Herman, M. [Vuje, Trnava (Slovakia)

    1997-12-31

    At operated Czech and Slovak nuclear power plants the 80 % criteria for crack or other bulk defect depth is used for steam generator heat exchanging tubes plugging. This criteria was accepted as the recommendation of designer of WWER steam generators. Verification of this criteria was the objective of experimental program performed by Vitkovice, J.S.C., UJV Rez, J.S.C. and Vuje Trnava, J.S.C .. Within this program the following factors were studied: (1) Influence of secondary water chemistry on defects initiation and propagation, (2) Statistical evaluation of corrosion defects progression at operated SG, and (3) Determination of critical pressure for tube rupture as a function of eddy current indications. In this presentation items (2) and (3) are considered.

  4. Innovations on the workplace of the irradiation experiments group

    International Nuclear Information System (INIS)

    Chamrad, B.

    1978-01-01

    EROS-76, the electronic control system for irradiation probes at UJV Rez is described. Irradiation probes of the CHOUCA-T type are used, each with a separate control system placed in a self-contained cabinet. Experimental parameters are automatically monitored in preset time intervals by an electric typewriter and are simultaneously punched on tape. Operating parameters are recorded by analog instruments and are used for equipment function checks. An operation log is part of the whole system. The EROS-76 system's operating capability and good function was well proven in experimental operation. Currently, stage two of the construction is under way named EROS-78. A brief description is given of the workplace construction including organization and personnel characteristics. (J.P.)

  5. Prospects of closed-circuit television in detecting surface defects

    International Nuclear Information System (INIS)

    Kaisler, L. et al.

    The use is discussed of closed-circuit television for optical in-service testing of surface defects of nuclear reactors. Experience gained by UJV Rez with in-service testing of the WWR-S reactor is briefly reported. Main attention is devoted to recognizability of defects and to determining the fundamental conditions of the applicability and limitations of the closed-circuit television method. In experiments, resolution of the method was tested and the role of the human factor was assessed in evaluating the results. The need was stressed of thorough training of operators. Based on the experiments conducted, considerations are presented regarding modifications of the individual elements of the tv chain aimed at improved quality of information and a limited role of the observer. (B.S.)

  6. Plugging criteria for WWER SG tubes

    Energy Technology Data Exchange (ETDEWEB)

    Papp, L; Wilam, M [Vitkovice NPP Services (Switzerland); Herman, M [Vuje, Trnava (Slovakia)

    1998-12-31

    At operated Czech and Slovak nuclear power plants the 80 % criteria for crack or other bulk defect depth is used for steam generator heat exchanging tubes plugging. This criteria was accepted as the recommendation of designer of WWER steam generators. Verification of this criteria was the objective of experimental program performed by Vitkovice, J.S.C., UJV Rez, J.S.C. and Vuje Trnava, J.S.C .. Within this program the following factors were studied: (1) Influence of secondary water chemistry on defects initiation and propagation, (2) Statistical evaluation of corrosion defects progression at operated SG, and (3) Determination of critical pressure for tube rupture as a function of eddy current indications. In this presentation items (2) and (3) are considered.

  7. In vessel retention for VVER 1000 - Experimental work

    International Nuclear Information System (INIS)

    Batek, D.

    2015-01-01

    After Fukushima accident, the nuclear community realized that it is necessary to have strategy and solution for severe accident management. In Vessel Retention (IVR) of corium is an important strategy to mitigate the consequences of a severe accident. In this poster the author reviews the present status of experimental works made by UJV (Czech Republic) from 2012 until now, on the IVR strategy specifically applied for the VVER 1000 unit. The BESTH 1 experiment was prepared to test the behavior of the RPV (Reactor Pressure Vessel) surface under 2 configurations: clean and corroded. BESTH 2 experiment is a modification of BESTH 1 experiment in order to get greater thermal fluxes. The BESTH 3 facility is a large scale experiment that is under extensive design (2016-2017) whose main objective will be to investigate the results of vast analytical works made by experts with specialization of severe accident phenomenology

  8. Calculation of local characteristics of velocity field in turbulent coolant flow in fast reactor fuel assembly

    International Nuclear Information System (INIS)

    Muehlbauer, P.

    1981-08-01

    Experience is described gained with the application of computer code VELASCO in calculating the velocity field in fast reactor fuel assemblies taking into account configuration disturbances due to fuel pin displacement. Theoretical results are compared with the results of experiments conducted by UJV on aerodynamic models HEM-1 (model of the fuel assembly central part) and HEM-2 (model of the fuel assembly peripheral part). The results are reported of calculating the distribution of shear stress in wetted rod surfaces and in the assembly wall (model HEM-2) and the corresponding experimental results are shown. The shear stress distribution in wetted surfaces obtained using the VELASCO code allowed forming an opinion on the code capability of comprising local parameters of turbulent flow through a fuel rod bundle. The applicability was also tested of the code for calculating mean velocities in the individual zones, eg., in elementary cells. (B.S.)

  9. Report on advances '87

    International Nuclear Information System (INIS)

    Havelka, S.

    1988-02-01

    The most important scientific, technical and partly also economic results attained in 1987 by UJV Rez are summed up. Research and development work in nuclear power is oriented to nuclear safety, reactor physics, reactor materials, reactor technology, chemistry of the fuel cycle and standardization. In the field of the use of ionizing radiation the problems resolved included radiation technologies, radiopharmaceuticals, neutron activation analysis and neutron radiography. Some of the works were also oriented to radiation safety. In the field of production and services the study was oriented to the production of radiopharmaceuticals, semiconductor ionizing radiation detectors, services of the Central Control Laboratory, irradiation services, computer and information services. The social program of the Institute was oriented to upgrading personnel, the housing programme, catering, working environment and recreation. The organization structure of the Institute is given. (J.B.). 36 figs., 11 tabs., 101 refs., 10 colour illustrations in Supplement

  10. 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

  11. 2008 EUROSAFE Forum. The role of TSOs in view of rising demand for safety expertise

    International Nuclear Information System (INIS)

    May, Horst; Jansen, Florian; Seubert, Armin; Kaulard, Joerg; Weber, Stefan; Sternkopf, Juergen

    2009-01-01

    Some 400 guests from 27 nations attended the 10 th EUROSAFE Forum for Nuclear Safety in Paris in early November 2008. In addition to the proven specialized seminars, the event this time focused on the role of TSOs in view of the rising demand for safety expertise. Jacques Repussard, Director General of IRSN; Lothar Hahn, Technical-Scientific Managing Director, GRS; Benoit de Boeck, Managing Director, Bel V; Ales John, Director General, UJV (Nuclear Research Institute Rez plc); and Seppo Vuori, Chief Scientist, VTT, stressed the importance of close cooperation among European TSOs. In Europe, the need was becoming more and more apparent to harmonize safety requirements and standardize licensing criteria. The four specialized seminars discussed these topics: - Seminar 1: Safety of nuclear installations assessment and research. - Seminar 2: Environmental protection and radiation protection. - Seminar 3: Waste management and the environment. - Seminar 4: Safeguarding nuclear materials and plants. The presentations can be found under www.eurosafe-forum.org. The 11 th EUROSAFE Forum will be held in Brussels on November 2 and 3, 2009. (orig.)

  12. Spent fuel pool risk analysis for the Dukovany NPP

    Energy Technology Data Exchange (ETDEWEB)

    Hust' ak, S.; Jaros, M.; Kubicek, J. [UJV Rez, a.s., Husinec-Rez (Czech Republic)

    2013-07-01

    UJV Rez, a.s. maintains a Living Probabilistic Safety Assessment (Living PSA) program for Dukovany Nuclear Power Plant (NPP) in the Czech Republic. This project has been established as a framework for activities related to risk assessment and to support for risk-informed decision making at this plant. The most extensively used PSA application at Dukovany NPP is risk monitoring of instantaneous (point-in-time) risk during plant operation, especially for the purpose of configuration risk management during plant scheduled outages to avoid risk significant configurations. The scope of PSA for Dukovany NPP includes also determination of a risk contribution from spent fuel pool (SFP) operation to provide recommendations for the prevention and mitigation of SFP accidents and to be applicable for configuration risk management. This paper describes the analysis of internal initiating events (IEs) in PSA for Dukovany NPP, which can contribute to the risk from SFP operation. The analysis of those IEs was done more thoroughly in the PSA for Dukovany NPP in order to be used in instantaneous risk monitoring. (orig.)

  13. Practical results of the MESA 1 line calcinator trial operation

    International Nuclear Information System (INIS)

    Napravnik, J.; Sazavsky, P.; Skaba, V.; Zahalka, F.; Vild, J.; Kulovany, J.

    1987-01-01

    Mobile calcination and cementation unit MESA 1 was designed and built by UJV Rez in cooperation with many enterprises, mainly with the Kralovopolske Strojirny Brno. This facility for direct fixation of liquid radioactive wastes was experimentally tested using model non-radioactive solutions and model and actual wastes from the Jaslovske Bohunice nuclear power plant. The calciner was run in trial operation at the Kralovopolske SAtrojirny Brno. A total of 1.3 m 3 of model solutions was processed into 180 kg of calcinate. The fixation of the calcinate in cement, the times of solidification and of hardening and the moisture content of concrete blocks were studied. The application was also tested of the calciner in drying ion exchangers from WWER-440 prior to their bituminization. Following the despatch of the cementation module to the Chernobyl nuclear power plant, the direct calcination module was tested at Dukovany together with an auxiliary module which makes possible self-contained calciner operation. Model non-radioactive solutions from the Dukovany nuclear power plant were treated containing H 3 BO 3 and NaNO 3 as main components. The usability in actual conditions of the mobile calcination and cementation unit for radioactive wastes was tested in a total of about 70 operating hours. (E.S.). 2 figs., 2 refs

  14. External events analysis in PSA studies for Czech NPPs

    International Nuclear Information System (INIS)

    Holy, J.; Hustak, S.; Kolar, L.; Jaros, M.; Hladky, M.; Mlady, O.

    2014-01-01

    The purpose of the paper is to summarize current status of natural external hazards analysis in the PSA projects maintained in Czech Republic for both Czech NPPs - Dukovany and Temelin. The focus of the presentation is put upon the basic milestones in external event analysis effort - identification of external hazards important for Czech NPPs sites, screening out of the irrelevant hazards, modeling of plant response to the initiating events, including the basic activities regarding vulnerability and fragility analysis (supported with on-site analysis), quantification of accident sequences, interpretation of results and development of measures decreasing external events risk. The following external hazards are discussed in the paper, which have been addressed during several last years in PSA projects for Czech NPPs: 1)seismicity, 2)extremely low temperature 3)extremely high temperature 4)extreme wind 5)extreme precipitation (water, snow) 6)transport of dangerous substances (as an example of man-made hazard with some differences identified in comparison with natural hazards) 7)other hazards, which are not considered as very important for Czech NPPs, were screened out in the initial phase of the analysis, but are known as potential problem areas abroad. The paper is a result of coordinated effort with participation of experts and staff from engineering support organization UJV Rez, a.s. and NPPs located in Czech Republic - Dukovany and Temelin. (authors)

  15. Study on the weediness of winter wheat in a long-term fertilization field experiment.

    Science.gov (United States)

    Lehoczky, E; Kismányoky, A; Kismányoky, T

    2006-01-01

    The study was carried out in Keszthely, in the long-term fertilization field experiment in April of 2005. In the experiment we had opportunity to compare the weediness in NPK and NPK + FYM* treatments, and we could study the effect of increasing N dosis on the weeds and winter wheat. The weed survey was made on the 20th of April at the end of tillering. For the weed survey used the Balázs-Ujvárosi method. After that we collected all the weeds from the plots per 1 m2. We counted, measured the fresh and dry matter weight of aerial parts. Winter wheat sampels were taken also from all plots (1 running meter per plot). In the experiment 10 weed species were found, 9 annual: Ambrosia artemisiifolia, Consolida regalis, Galium aparine, Lamiunt amplexicaule, Matricaria inodora, Papaver rhoeas, Stellaria media, Veronica hederifolia, Veronica triphyllos, and 1 perennial: Cirsium arvense. Veronica hederifolia was the dominant species in both fertilized plots, Stellaria media has the second highest weed coverage. The manuring treatments, and the N-dosis has important and significantly effect to the weedeness and the biomass production of winter wheat. On the control plots was the relation of biomass weight of weeds the highest. This relation reduced to the effect of N treatments, wich had an favorable effect on the winter wheat.

  16. Role of nuclear energy in long term sustainable energy development and research needs from the point of view of UJV Rez a.s

    International Nuclear Information System (INIS)

    Pazdera, F.; Misak, J.

    2005-01-01

    In this presentation author deals with Increasing power at Dukovany NPP, operational and safety features of Belene NPP as well as with worldwide reserves and prices of uranium, thorium, natural gas, petroleum and coal.

  17. Survey of weed composition befor maize sowing in long-term fertilization experiment.

    Science.gov (United States)

    Kismányoky, A; Lehoczky, E

    2007-01-01

    The study was carried out in a long-term fertilization field experiment of the Experimental Station of University of Pannonia, Department of Crop Science and Soil Science in 2006. The Long-term fertilization experiment was set up in 1983. In the experiment, the success of the weeds ability to grow under the influence of NPK, NPK + FYM* and NPK + straw treatments was compared, and the effect of increasing Nitrogen dosing on weediness was studied. The bifactorial test was arranged in split plot design with three replications. Treatment A: nutrient: NPK, NPK + 35 t/ha FYM* and NPK + straw manure. Treatment B: N kg/ha(-1) N0-N4 (0, 70, 140, 210, 280), and 100 kg P2O5 ha(-1) & 100 kg K20. The weed survey was made on 2nd of May 2006. There were spraying no herbicide until the survey. For the weed survey the Balázs-Ujvárosi coenological method was applied. Altogether, we have found 23 weed species in the trial. In the NPK treatment there were 20 species, in the treatment NPK+organic manure there were 17 species and in the NPK+ stalk rest treatment there were 16 weed species. The most dominant of the weeds on the NPK and NPK+straw manure treatments was Veronica hederifolia while on the fertilizer + FYM, the A. theophrasti was most dominant. The average weed covering value of the treatment NPK + FYM was 1.36 times higher (10.87%) than that of treatment NPK only (7.97%) and 3.65 times higher than on the NPK + straw manure treatment.

  18. Estimation of frequency of occurrence of extreme natural external events of very high intensity on the base of (non)available data - Estimation of frequency of rare natural external events of very high intensity on the base of (non)available data

    International Nuclear Information System (INIS)

    Holy, J.; Kolar, L.; Jaros, M.; Hladky, M.; Mlady, O.

    2014-01-01

    from engineering support organization UJV Rez, a.s. and both NPPs located in Czech Republic - Dukovany and Temelin. (authors)

  19. The future Jules Horowitz material test reactor: A major European research infrastructure for sustaining the international irradiation capacity

    International Nuclear Information System (INIS)

    Parrat, D.; Bignan, G.; Chauvin, J.; Gonnier, C.

    2011-01-01

    Multipurpose experimental reactors are now key infrastructures, in complement of prediction capabilities gained thanks to progresses in the modelling, for supporting nuclear energy in terms of safety, ageing management, innovation capacity, economical performances and training. However the European situation in this field is characterized by ageing large infrastructures, which could face to operational issues in the coming years and could jeopardize the knowledge acquisition and the nuclear product qualification. Moreover some specific supplies related to the public demand could be strongly affected (e.g. radiopharmaceutical targets). To avoid a lack in the experimental capacity offer at the European level, the CEA has launched the Jules Horowitz material test reactor (JHR) international program, in the frame of a Consortium gathering EDF (FR), AREVA (FR), the European Commission (EU), SCK.CEN (BE), VTT (FI), CIEMAT (SP), VATTENFALL (SE), UJV (CZ), JAEA (JP) and the DAE (IN). The JHR will be a 100 MW tank pool reactor and will have several experimental locations either inside the reactor core or outside the reactor tank in a reflector constituted by beryllium blocks. Excavation works started mid-2007 on the CEA Cadarache site in the southeast of France. After the construction permit delivery gained in September 2007, building construction began at the beginning of 2009. Reactor start-up is scheduled in 2016. The JHR is designed to offer up-to-date irradiation experimental capabilities for studying nuclear material and fuel behaviour under irradiation in a modern safety frame, mainly due to: 1) High values of fast and thermal neutron fluxes in the core and high thermal neutron flux in the reflector (producing typically twice more material damages per year than available today in European MTRs); 2) A large variety of experimental devices capable to reproduce environment conditions of mainly light water reactors (LWRs) and sodium fast reactors; 3) Several equipment

  20. The future Jules Horowitz material testing reactor: An opportunity for developing international collaborations on a major European irradiation infrastructure

    International Nuclear Information System (INIS)

    Parrat, D.; Bignan, G.; Maugard, B.; Gonnier, C.; Blandin, C.

    2015-01-01

    Development process of a fuel product or a nuclear material before using at an industrial scale in a power reactor ranges from characterization of the material itself under neutronic flux up to its qualification in accidental conditions. Irradiations in Material Testing Reactors (MTRs) are in practice the basis of the whole process, in complement of prediction capabilities gained by modelling. Dedicated experimental reactors play also an important complementary role for some specific integral tests (e.g. RIA tests). Irradiations of precursors in power reactors are often limited to products which present a slight design evolution compare to the standard product or are implemented for further tests when a statistical approach is useful for defining a safety criterion. However European MTR park status is characterized by ageing infrastructures, which could cause operational issues in coming years, either on technological or on safety point of views. Moreover some specific supplies related to the public demand could be strongly affected (e.g. radiopharmaceutical targets). To avoid a lack in irradiation capacity offer at European level, CEA launched the Jules Horowitz Material Testing Reactor (JHR) international program, in the frame of a Consortium gathering also EDF (FR), AREVA (FR), European Commission (EU), SCK.CEN (BE), VTT (FI), CIEMAT (SP), STUDSVIK (SE), UJV (CZ), NNL (UK), IAEC (IL), DAE (IN) and as associated partnership: JAEA (JP). Some institutions in this list are themselves the flagship of a national Consortium. Discussions for enlarging participation are on-going with other countries, as JHR Consortium is open to new member entrance until JHR completion. The Jules Horowitz Material Testing Reactor (JHR MTR) is under construction at CEA Cadarache in southern France and will be an important international User Facility for R&D in support to the nuclear industry, research centres, regulatory bodies and TSO, and academic institutions. It represents a unique

  1. Experimental facilities for Generation IV reactors research

    International Nuclear Information System (INIS)

    Krecanova, E.; Di Gabriele, F.; Berka, J.; Zychova, M.; Macak, J.; Vojacek, A.

    2013-06-01

    Centrum Vyzkumu Rez (CVR) is research and development Company situated in Czech Republic and member of the UJV group. One of its major fields is material research for Generation IV reactor concepts, especially supercritical water-cooled reactor (SCWR), very high temperature/gas-cooled fast reactor (VHTR/GFR) and lead-cooled fast reactor (LFR). The CVR is equipped by and is building unique experimental facilities which simulate the environment in the active zones of these reactor concepts and enable to pre-qualify and to select proper constructional materials for the most stressed components of the facility (cladding, vessel, piping). New infrastructure is founded within the Sustainable Energy project focused on implementation the Generation IV and fusion experimental facilities. The research of SCWR concept is divided to research and development of the constructional materials ensured by SuperCritical Water Loop (SCWL) and fuel components research on Fuel Qualification Test loop (SCWL-FQT). SCWL provides environment of the primary circuits of European SCWR, pressure 25 MPa, temperature 600 deg. C and its major purpose is to simulate behavior of the primary medium and candidate constructional materials. On-line monitoring system is included to collect the operational data relevant to experiment and its evaluation (pH, conductivity, chemical species concentration). SCWL-FQT is facility focused on the behavior of cladding material and fuel at the conditions of so-called preheater, the first pass of the medium through the fuel (in case of European SCWR concept). The conditions are 450 deg. C and 25 MPa. SCWL-FQT is unique facility enabling research of the shortened fuel rods. VHTR/GFR research covers material testing and also cleaning methods of the medium in primary circuit. The High Temperature Helium Loop (HTHL) enables exposure of materials and simulates the VHTR/GFR core environment to analyze the behavior of medium, especially in presence of organic compounds and

  2. Physiological bases for detecting and predicting photoinhibition of aquatic photosynthesis by PAR and UV radiation

    International Nuclear Information System (INIS)

    Neale, P.J.; Cullen, J.J.; Lesser, M.P.; Melis, A.

    1993-01-01

    Phytoplankton photosynthesis is the basis of almost all aquatic primary production in the world's oceans, estuaries and lakes. Oceanic primary production is a major portion of the global carbon budget (see other contributions this volume). Currently, we are unable to account for all the CO 2 that is leaving the atmosphere and debate continues whether the ''missing carbon'' is going into either terrestrial and oceanic sinks (7). In this context, it is important to improve our knowledge of how phytoplankton photosynthesis responds to the aquatic environment. The aquatic light environment is primary among several factors governing aquatic photosynthesis. To understand phytoplankton response to aquatic irradiance, we must consider how light propagates underwater, variations in light spectral quality as well as intensity. Also important is how these optical characteristics relate to processes of light absorption and utilization by phytoplankton cells. Considerable progress has been made on answering many of these questions (e.g. 27). One topic, phytoplankton responses to irradiance stress induced by photosynthetically available radiation (PAR2) and UJV, has become increasingly important. The primary consequence in both cases is a time-dependent loss of photosynthetic activity (photo inhibition). Concern over the effects of solar UV irradiance has recently intensified with the advent of stratospheric ozone depletion, which allows for an increase of the mid-ultraviolet (UVB 280-320 nm)irradiance, especially in the Antarctic. The sensitivity of phytoplankton photosynthesis to irradiance stress can be readily demonstrated (36), however,showing whether this stress actually occurs in the aquatic environment remains difficult. The essential problem is that phytoplankton are in suspension. Their irradiance exposure will be determined by mixing processes that transport cells over a vertical gradient in light availability. The response to irradiance

  3. Needs for European decommissioning academy (EDA)

    International Nuclear Information System (INIS)

    Slugen, Vladimir

    2014-01-01

    According to analyses presented at EC meeting focused on decommissioning organized at 11.9.2012 in Brussels, it was stated that at least 500 new international experts for decommissioning will be needed in Europe up to 2025, which means about 35 per year. Having in mind the actual EHRO-N report from 2013 focused on operation of nuclear facilities and an assumption that the ratio between nuclear experts, nuclearized and nuclear aware people is comparable also for decommissioning, as well as the fact that the special study branch for decommissioning in the European countries almost does not exist, this European Decommissioning Academy (EDA) could be helpful in the over-bridging this gap. The main goal is - from about 74% of nuclearized experts (graduated at different technical Universities and increased their nuclear knowledge and skills mostly via on-job training and often in the area of NPP operation) to create nuclear experts for decommissioning via our post-gradual coursed organized in two semester study at our Academy, which will include the lessons, practical exercises in our laboratories, on-site training at NPP V-1 in Jaslovske Bohunice, Slovakia as well as 3 days technical tour to JAVYS (Slovakia), UJV Rez (Czech Rep.) and PURAM (Hungary), respectively. Beside the exams in selected topics (courses), the final thesis written under supervision of recognized experts will be the precondition for graduation and certification of the participants. For the first run of the EDA scheduled on 2014 we would like to focus on VVER decommissioning issues because this reactor type is the most distributed design in the world and many of these units are actually in decommissioning process or will be decommissioned in the near future in Europe. The growing decommissioning market creates a potential for new activities, with highly skilled jobs in an innovative field, involving high-level technologies. A clear global positioning of the EU will stimulate the export of know-how to

  4. Probabilistic Safety Assessment (PSA) of Natural External Hazards Including Earthquakes. Workshop Proceedings, Prague, Czech Republic, 17-20 June 2013

    International Nuclear Information System (INIS)

    2014-01-01

    The Fukushima Dai-ichi accident triggered discussions about the significance of external hazards and their treatment in safety analyses. In addition, stress tests results have shown vulnerabilities and potential of cliff-edge effects in plant responses to external hazards and have identified possibilities and priorities for improvements and safety measures' implementation at specific sites and designs. In order to address these issues and provide relevant conclusions and recommendations to CSNI and CNRA, the CSNI Working Group on Risk Assessment (WGRISK) directed, in cooperation with the CSNI Working Group on Integrity and Ageing of Components and Structures (WGIAGE), a workshop hosted by UJV Rez. The key objectives of the workshop were to collect information from the OECD member states on methods and approaches being used, and experience gained in probabilistic safety assessment of natural external hazards, as well as to support the fulfillment of the CSNI task on 'PSA of natural external hazards including earthquakes'. These objectives are described more in detail in the introduction in Chapter 1 of this report. The WGRISK activities preceding the workshop and leading to the decision to organize it are described in Chapter 2 of this report. The focus of the workshop was on external events PSA for nuclear power plants, including all modes of operation. The workshop scope was generally limited to external, natural hazards, including those hazards where the distinction between natural and man-made hazards is not sharp. The detailed information about the presentations, discussions, and results of the workshop is presented in Chapter 3 of this report. Some general conclusions were agreed on during the workshop, which are presented in the following paragraphs. - The lessons learned from the Fukushima Dai-ichi reactor accidents and related actions at the national, regional, and global level have emphasized the importance to assess risks associated (authors) with