Experimental nuclear physics in Vietnam - recent status

International Nuclear Information System (INIS)

Tran Thanh Minh

1995-01-01

Status of research works on experimental nuclear physics in Vietnam is reviewed. Vietnam institutions and main instruments for nuclear research are listed. The results on physics and technology of nuclear reactor, neutron physics, nuclear reactions, radiological safety are mentioned. (N.H.A). 6 tabs, 4 figs

Low-lying nuclear levels and radiative transitions in hadronic atoms

International Nuclear Information System (INIS)

Popov, V.S.; Kudryavtsev, A.E.; Lisin, V.I.; Mur, V.D.

1985-01-01

The analytic theory of nuclear level shifts permit the position of the nuclear level perturbing the Coulomb spectrum to be calculated on the basis of the magnitude of the level shift of a hadron atom. As an example the K -4 He atom is discussed. The experimental data on the 2p-level shift indicate that a weakly bound p-state with a binding energy and width epsilon approximately γ approximately 0.5 MeV may exist in the system. The probabilities for radiative transitions to this level and the cross section for its creation in a nuclear reaction with 6 Li are calculated. The possible existence of weakly coupled K - and anti p states for other light nuclei is discussed. An exact solution of the model Coulomb problem with short range interaction is obtained and this permits the limits of validity of the initial approximations to be determined

Experimental techniques in nuclear and particle physics

International Nuclear Information System (INIS)

Tavernier, Stefaan

2010-01-01

The book is based on a course in nuclear and particle physics that the author has taught over many years to physics students, students in nuclear engineering and students in biomedical engineering. It provides the basic understanding that any student or researcher using such instruments and techniques should have about the subject. After an introduction to the structure of matter at the subatomic scale, it covers the experimental aspects of nuclear and particle physics. Ideally complementing a theoretically-oriented textbook on nuclear physics and/or particle physics, it introduces the reader to the different techniques used in nuclear and particle physics to accelerate particles and to measurement techniques (detectors) in nuclear and particle physics. The main subjects treated are: interactions of subatomic particles in matter; particle accelerators; basics of different types of detectors; and nuclear electronics. The book will be of interest to undergraduates, graduates and researchers in both particle and nuclear physics. For the physicists it is a good introduction to all experimental aspects of nuclear and particle physics. Nuclear engineers will appreciate the nuclear measurement techniques, while biomedical engineers can learn about measuring ionising radiation, the use of accelerators for radiotherapy. What's more, worked examples, end-of-chapter exercises, and appendices with key constants, properties and relationships supplement the textual material. (orig.)

Experimental nuclear physics research in Hungary

International Nuclear Information System (INIS)

Koltay, Ede.

1984-01-01

The status and recent results of experimental nuclear physics in Hungary is reviewed. The basic nuclear sciences, instrumental background and international cooperation are discussed. Personal problems and the effects of the international scientific deconjuncture are described. The applied nuclear and interdisciplinary researches play an important role in Hungarian nuclear physics. Some problems of cooperation of Hungarian nuclear and other research institutes applying or producing nuclear analytical technology are reviewed. The new instrument, the Debrecen cyclotron under construction gives new possibilities to basic and applied researches. A new field of Hungarian nuclear physics is the fusion and plasma research using tokamak equipment, the main topics of which are plasma diagnostics and fusion control systems. Some practical applications of Hungarian nuclear physical results, e.g. establishment of new analytical techniques like PIXE, RBS, PIGE, ESCA, etc. are summarized. (D.Gy.)

Nuclear level density variation with angular momentum induced shape transition

International Nuclear Information System (INIS)

Aggarwal, Mamta

2016-01-01

Variation of Nuclear level density (NLD) with the excitation energy and angular momentum in particular has been a topic of interest in the recent past and there have been continuous efforts in this direction on the theoretical and experimental fronts but a conclusive trend in the variation of nuclear level density parameter with angular momentum has not been achieved so far. A comprehensive investigation of N=68 isotones around the compound nucleus 119 Sb from neutron rich 112 Ru (Z=44) to neutron deficient 127 Pr (Z= 59) nuclei is presented to understand the angular momentum induced variations in inverse level density parameter and the possible influence of deformation and structural transitions on the variations on NLd

VI European Summer School on Experimental Nuclear Astrophysics

Science.gov (United States)

The European Summer School on Experimental Nuclear Astrophysics has reached the sixth edition, marking the tenth year's anniversary. The spirit of the school is to provide a very important occasion for a deep education of young researchers about the main topics of experimental nuclear astrophysics. Moreover, it should be regarded as a forum for the discussion of the last-decade research activity. Lectures are focused on various aspects of primordial and stellar nucleosynthesis, including novel experimental approaches and detectors, indirect methods and radioactive ion beams. Moreover, in order to give a wide educational offer, some lectures cover complementary subjects of nuclear astrophysics such as gamma ray astronomy, neutron-induced reactions, short-lived radionuclides, weak interaction and cutting-edge facilities used to investigate nuclear reactions of interest for astrophysics. Large room is also given to young researcher oral contributions. Traditionally, particular attention is devoted to the participation of students from less-favoured countries, especially from the southern coast of the Mediterranean Sea. The school is organised by the Catania Nuclear Astrophysics research group with the collaboration of Dipartimento di Fisica e Astromomia - Università di Catania and Laboratori Nazionali del Sud - Istituto Nazionale di Fisica Nucleare.

Experimental studies of nuclear astrophysics

International Nuclear Information System (INIS)

He Jianjun; Zhou Xiaohong; Zhang Yuhu

2013-01-01

Nuclear astrophysics is an interdisciplinary subject combining micro-scale nuclear physics and macro-scale astrophysics. Its main aims are to understand the origin and evolution of the elements in the universe, the time scale of stellar evolution, the stellar environment and sites, the energy generation of stars from thermonuclear processes and its impact on stellar evolution and the mechanisms driving astrophysical phenomena, and the structure and property of compact stars. This paper presents the significance and current research status of nuclear astrophysics; we introduce some fundamental concepts, the nuclear physics input parameters required by certain astrophysics models, and some widely-used experimental approaches in nuclear astrophysics research. The potential and feasibility of research in this field using China’s current and planned large-scale scientific facilities are analyzed briefly. Finally, the prospects of the establishing a deep underground science and engineering laboratory in China are envisaged. (authors)

Perspectives of experimental nuclear physics research at RBI Croatia

International Nuclear Information System (INIS)

Soic, N.

2009-01-01

Experimental nuclear physics has been one of the top research activities at the Rudjer Boskovic Institute, the largest and leading Croatian research center in science and applications. The RBI nuclear physics group has strong link with the researchers at the University of Zagreb. RBI scientists perform experiments at the RBI Tandem accelerator facility and at the top European experimental facilities in collaboration with the prominent research groups in the field. Current status of the RBI experimental nuclear physics research and our recent activities aimed to strengthen our position at the RBI and to increase our international reputation and impact in collaborative projects will be presented. Part of these activities is focused on local accelerator facilities, at present mainly used for application research, and their increased usage for nuclear physics research and for development and testing of novel research equipment for large international facilities. Upgrade of the local research equipment is on the way through FP7 REGPOT project 'CLUNA: Clustering phenomena in nuclear physics: strengthening of the Zagreb-Catania-Birmingham partnership'. Recently, steps to exploit potential of the facility for nuclear astrophysics research have been initiated. Possible future actions for further strengthening of the RBI experimental nuclear physics research will be discussed.(author)

Nuclear test-experimental science annual report, Fiscal year 1990

International Nuclear Information System (INIS)

Struble, G.L.; Middleton, C.; Anderson, S.E.; Cherniak, J.; Donohue, M.L.; Francke, A.; Hedman, I.; Kirvel, R.D.

1991-01-01

Fiscal year 1990 was another year of outstanding accomplishments for the Nuclear Test-Experimental Science (NTES) Program at Lawrence Livermore National Laboratory (LLNL). We continued to make progress to enhance the experimental science in the Weapons Program and to improve the operational efficiency and productivity of the Nuclear Test Program

Revised experimental program on the nuclear ship 'Mutsu'

International Nuclear Information System (INIS)

Mori, Yuichi

1985-01-01

The experimental program on the nuclear ship ''Mutsu'' has been revised by the Government. And, the responsible organization for n. s. Mutsu was turned to Japan Atomic Energy Research Institute (JAERI) from Japan Nuclear-ship Development Agency. The revised, new experimental program is as follows. (1) Experimental navigation of n. s. Mutsu is made with the already loaded 1st reactor core for about one year. (2) The mooring port for n. s. Mutsu is in a minimum scale. (3) Upon termination of the experimental navigation, n. s. Mutsu is immediately decommissioned. (4) Power-up test and experimental navigation of n. s. Mutsu are made in fiscal 1989 to 1990. The policy of research and development with n. s. Mutsu and the works assigned to JAERI with n. s. Mutsu are described. (Mori, K.)

High level nuclear wastes

International Nuclear Information System (INIS)

Lopez Perez, B.

1987-01-01

The transformations involved in the nuclear fuels during the burn-up at the power nuclear reactors for burn-up levels of 33.000 MWd/th are considered. Graphs and data on the radioactivity variation with the cooling time and heat power of the irradiated fuel are presented. Likewise, the cycle of the fuel in light water reactors is presented and the alternatives for the nuclear waste management are discussed. A brief description of the management of the spent fuel as a high level nuclear waste is shown, explaining the reprocessing and giving data about the fission products and their radioactivities, which must be considered on the vitrification processes. On the final storage of the nuclear waste into depth geological burials, both alternatives are coincident. The countries supporting the reprocessing are indicated and the Spanish programm defined in the Plan Energetico Nacional (PEN) is shortly reviewed. (author) 8 figs., 4 tabs

Experimental Seminar on Nuclear Energy for Teachers

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-02-01

`Experimental Seminar on Nuclear Energy for Teachers` was conducted and sponsored by the Science and Technology Agency. And in order to understand nuclear energy properly through lectures and experiments with good results inclass, the seminar carried out for teachers of high schools and junior high schools by the Nuclear Technology and Education Center (NuTEC), Japan Atomic Energy Research Institute in 1990 FY to 1997 FY. In this report, details of the seminars in the above period are described and No.1 to 17 of Communication Letters of Experimental Seminar on Nuclear Energy` started at 1992 FY are described also. These letters were prepared for attendant follow-up program. And programs of recent seminars, future`s seminars, impressions and comments from attendants, reports from actual classes and others are described in these letters and they are very useful for educational classes on nuclear energy by other teachers. Therefore contents of the letters are listed and easy to refer. A part of this educational task was transferred to the Radiation Application Development Association in 1997 FY and other parts were transferred in 1998 FY. (author)

Angular momentum dependence of the nuclear level density parameter

International Nuclear Information System (INIS)

Aggarwal, Mamta; Kailas, S.

2010-01-01

Dependence of nuclear level density parameter on the angular momentum and temperature is investigated in a theoretical framework using the statistical theory of hot rotating nuclei. The structural effects are incorporated by including shell correction, shape, and deformation. The nuclei around Z≅50 with an excitation energy range of 30 to 40 MeV are considered. The calculations are in good agreement with the experimentally deduced inverse level density parameter values especially for 109 In, 113 Sb, 122 Te, 123 I, and 127 Cs nuclei.

Experimental qualification of nuclear components

Energy Technology Data Exchange (ETDEWEB)

Alliot, P; Fronte, T; Genty, F [FRAMATOME - Cedex 16, Paris la Defense (France)

1988-07-01

In the process of showing the adequacy of the seismic design of French PWR reactor, Fermat has repeatedly used dynamic testing on actual nuclear reactor components both on site and in manufacturing shops. The objective and results of a few representative examples of this on-site experimental verification are presented in this paper: the experimental dynamic analysis of a manipulator crane; the investigation of the seismic behaviour of fuel storage racks equipped with aseismic bearing devices. Difficulties to select satisfactory testing methods are also discussed for the particular case of the electrical cabinets. (author)

Experimental qualification of nuclear components

International Nuclear Information System (INIS)

Alliot, P.; Fronte, T.; Genty, F.

1988-01-01

In the process of showing the adequacy of the seismic design of French PWR reactor, Fermat has repeatedly used dynamic testing on actual nuclear reactor components both on site and in manufacturing shops. The objective and results of a few representative examples of this on-site experimental verification are presented in this paper: the experimental dynamic analysis of a manipulator crane; the investigation of the seismic behaviour of fuel storage racks equipped with aseismic bearing devices. Difficulties to select satisfactory testing methods are also discussed for the particular case of the electrical cabinets. (author)

Experimental nuclear physics research challenges at low energies

Energy Technology Data Exchange (ETDEWEB)

Chavez, E.; Morales G, L. [UNAM, Instituto de Fisica, Circuito Exterior, Ciudad Universitaria, 04510 Mexico D. F. (Mexico); Murillo O, G. [ININ, Carretera Mexico-Toluca s/n, Ocoyoacac 52750, Estado de Mexico (Mexico)

2010-02-15

Experimental research with low energy beams of ions (a few MeV) in nuclear physics has gone through a phase transition along its evolution in fifty years because of the increasing complexity (and cost) of the equipment required to conduct meaningful investigations. Many of the small cyclotrons and Van de Graaff (single ended and tandem) accelerators have been used for the last three decades mostly in applications related to the characterization and modification of materials. Specific experimental investigations in nuclear physics with low energy accelerators are proposed in this work. Specifically we discuss the topic of nuclear radii measurements of radioactive species produced via (d,n) reactions. Some emphasis is given to the instrumentation required. (Author)

Experimental grounds for nuclear shape isomerism

International Nuclear Information System (INIS)

Makarenko, V.E.

1995-11-01

Experimental data on fission isomeric states of actinide nuclei - half lives, energies, quantum numbers, decay branches and spectroscopic properties - are discussed. Quite a few results find their explanation in the framework of nuclear shape isomerism hypothesis being the in-thing for about thirty years. Others seem to be the hints to the quasiparticle nature of fission isomers. The problem could be solved by direct measurement of nuclear spin for isomeric states. (author). 44 refs, 1 tab

Nuclear Test-Experimental Science: Annual report, fiscal year 1988

Energy Technology Data Exchange (ETDEWEB)

Struble, G.L.; Donohue, M.L.; Bucciarelli, G.; Hymer, J.D.; Kirvel, R.D.; Middleton, C.; Prono, J.; Reid, S.; Strack, B. (eds.)

1988-01-01

Fiscal year 1988 has been a significant, rewarding, and exciting period for Lawrence Livermore National Laboratory's nuclear testing program. It was significant in that the Laboratory's new director chose to focus strongly on the program's activities and to commit to a revitalized emphasis on testing and the experimental science that underlies it. It was rewarding in that revolutionary new measurement techniques were fielded on recent important and highly complicated underground nuclear tests with truly incredible results. And it was exciting in that the sophisticated and fundamental problems of weapons science that are now being addressed experimentally are yielding new challenges and understanding in ways that stimulate and reward the brightest and best of scientists. During FY88 the program was reorganized to emphasize our commitment to experimental science. The name of the program was changed to reflect this commitment, becoming the Nuclear Test-Experimental Science (NTES) Program.

Experimental nuclear physics in Vietnam - recent status

International Nuclear Information System (INIS)

Tran Thanh Minh

1995-01-01

It is really difficult to determine the exact date for the starting of nuclear physics research in Vietnam. Serious research on experimental nuclear physics began only since 1972 with the installation of such nuclear instrument like microtron accelerator, neutron generator, etc. During the past 20 years, hundred of research works have been published in local and foreign scientific journals. In the 5th national conference in Physics held in Hanoi in October 1993, at the Nuclear Physics section, 62 reports were presented reflecting the situation of nuclear physics research in the recent years, especially in the past five years. This review introduces its main results and formulates some perspectives of development in the late nineties in Vietnam. (K.A.). 27 refs., 4 figs., 6 tabs

Experimental techniques in nuclear and particle physics

CERN Document Server

Tavernier, Stefaan

2009-01-01

The book is based on a course in nuclear and particle physics that the author has taught over many years to physics students, students in nuclear engineering and students in biomedical engineering. It provides the basic understanding that any student or researcher using such instruments and techniques should have about the subject. After an introduction to the structure of matter at the subatomic scale, it covers the experimental aspects of nuclear and particle physics. Ideally complementing a theoretically-oriented textbook on nuclear physics and/or particle physics, it introduces the reader to the different techniques used in nuclear and particle physics to accelerate particles and to measurement techniques (detectors) in nuclear and particle physics. The main subjects treated are: interactions of subatomic particles in matter; particle accelerators; basics of different types of detectors; and nuclear electronics. The book will be of interest to undergraduates, graduates and researchers in both particle and...

Level density from realistic nuclear potentials

International Nuclear Information System (INIS)

Calboreanu, A.

2006-01-01

Nuclear level density of some nuclei is calculated using a realistic set of single particle states (sps). These states are derived from the parameterization of nuclear potentials that describe the observed sps over a large number of nuclei. This approach has the advantage that one can infer level density for nuclei that are inaccessible for a direct study, but are very important in astrophysical processes such as those close to the drip lines. Level densities at high excitation energies are very sensitive to the actual set of sps. The fact that the sps spectrum is finite has extraordinary consequences upon nuclear reaction yields due to the leveling-off of the level density at extremely high excitation energies wrongly attributed so far to other nuclear effects. Single-particle level density parameter a parameter is extracted by fitting the calculated densities to the standard Bethe formula

STACY and TRACY: nuclear criticality experimental facilities under construction

International Nuclear Information System (INIS)

Kobayashi, I.; Takeshita, I.; Yanagisawa, H.; Tsujino, T.

1992-01-01

Japan Atomic Energy Research Institute is constructing a Nuclear Fuel Cycle Safety Engineering Research Facility, NUCEF, where the following research themes essential for evaluating safety problems relating to back-end technology in nuclear fuel cycle facilities will be studied: nuclear criticality safety research; research on advanced reprocessing processes and partitioning; and research on transuranic waste treatment and disposal. To perform nuclear criticality safety research related to the reprocessing of light water reactor spent fuels, two criticality experimental facilities, STACY and TRACY, are under construction. STACY (Static Criticality Facility) will be used for the study of criticality conditions of solution fuels, uranium, plutonium and their mixtures. TRACY (Transient Criticality Facility) will be used to investigate criticality accident phenomena with uranium solutions. The construction progress and experimental programmes are described in this Paper. (author)

Nuclear systems of level measurement

International Nuclear Information System (INIS)

Lara, A.J.; Cabrera, M.J.

1992-01-01

In the industry there are processes in which is necessary to maintain the products level controlled which are handled for their transformation. The majority of such processes and by the operation conditions, they do not admit measure systems of level of invasive type then the application of nuclear techniques for level measurement results a big aid in these cases, since all the system installation is situated beyond frontiers of vessels that contain the product for measuring. In the Department of Nuclear Technology Applications of Mexican Petroleum Institute was developed a level measurement system by gamma rays transmission which operates in the Low Density Polyethylene plant of Petrochemical Complex Escolin at Poza Rica, Veracruz, Mexico. (Author)

Enhanced nuclear level decay in hot dense plasmas

International Nuclear Information System (INIS)

Gosselin, G.; Morel, P.

2004-01-01

A model of nuclear level decay in a plasma environment is described. Nuclear excitation and decay by photon processes, nuclear excitation by electron capture, and decay by internal conversion are taken into account. The electrons in the plasma are described by a relativistic average atom model for the bound electrons and by a relativistic Thomas-Fermi-Dirac model for the free electrons. Nuclear decay of isomeric level may be enhanced through an intermediate level lying above the isomer. An enhanced nuclear decay rate may occur for temperatures far below the excitation energy of the transition to the intermediate level. In most cases, the enhancement factor may reach several decades

Nuclear power: levels of safety

International Nuclear Information System (INIS)

Lidsky, L.M.

1988-01-01

The rise and fall of the nuclear power industry in the United States is a well-documented story with enough socio-technological conflict to fill dozens of scholarly, and not so scholarly, books. Whatever the reasons for the situation we are now in, and no matter how we apportion the blame, the ultimate choice of whether to use nuclear power in this country is made by the utilities and by the public. Their choices are, finally, based on some form of risk-benefit analysis. Such analysis is done in well-documented and apparently logical form by the utilities and in a rather more inchoate but not necessarily less accurate form by the public. Nuclear power has failed in the United States because both the real and perceived risks outweigh the potential benefits. The national decision not to rely upon nuclear power in its present form is not an irrational one. A wide ranging public balancing of risk and benefit requires a classification of risk which is clear and believable for the public to be able to assess the risks associated with given technological structures. The qualitative four-level safety ladder provides such a framework. Nuclear reactors have been designed which fit clearly and demonstrably into each of the possible qualitative safety levels. Surprisingly, it appears that safer may also mean cheaper. The intellectual and technical prerequisites are in hand for an important national decision. Deployment of a qualitatively different second generation of nuclear reactors can have important benefits for the United States. Surprisingly, it may well be the nuclear establishment itself, with enormous investments of money and pride in the existing nuclear systems, that rejects second generation reactors. It may be that we will not have a second generation of reactors until the first generation of nuclear engineers and nuclear power advocates has retired

Nuclear Data for Reactor Physics: Cross sections and level densities in the actinide region

Directory of Open Access Journals (Sweden)

Bernstein L.

2010-03-01

Full Text Available Nuclear data in the actinide region are particularly important because they are basis behind all simulations of nuclear reactor core behaviour over both long time scales (fuel depletion and waste production and short time scales (accident scenarios. Nuclear reaction cross sections must be known as precisely as possible so that core reaction rates can be accurately calculated. Although cross section measurements in this region have been widely performed, for certain nuclei, particularly those with short half lives, direct measurements are either very difficult or impossible and thus reactor simulations must rely on theoretical calculations or extrapolations from neighbouring nuclei. The greatest uncertainty in theoretical cross section calculations comes from the lack of knowledge of level densities, for which predicted values can often be incorrect by a factor of two or more. Therefore there is a strong case for a systematic experimental study of level densities in the actinide region for the purpose of a providing a stringent test of theoretical cross section calculations for nuclei where experimental cross section data are available and b for providing better estimations of cross sections for nuclei in which no cross section data are available.

Review of nuclear data improvement needs for nuclear radiation measurement techniques used at the CEA experimental reactor facilities

Directory of Open Access Journals (Sweden)

Destouches Christophe

2016-01-01

Full Text Available The constant improvement of the neutron and gamma calculation codes used in experimental nuclear reactors goes hand in hand with that of the associated nuclear data libraries. The validation of these calculation schemes always requires the confrontation with integral experiments performed in experimental reactors to be completed. Nuclear data of interest, straight as cross sections, or elaborated ones such as reactivity, are always derived from a reaction rate measurement which is the only measurable parameter in a nuclear sensor. So, in order to derive physical parameters from the electric signal of the sensor, one needs specific nuclear data libraries. This paper presents successively the main features of the measurement techniques used in the CEA experimental reactor facilities for the on-line and offline neutron/gamma flux characterizations: reactor dosimetry, neutron flux measurements with miniature fission chambers and Self Power Neutron Detector (SPND and gamma flux measurements with chamber ionization and TLD. For each technique, the nuclear data necessary for their interpretation will be presented, the main identified needs for improvement identified and an analysis of their impact on the quality of the measurement. Finally, a synthesis of the study will be done.

Experimental (Network) and Evaluated Nuclear Reaction Data at NDS

International Nuclear Information System (INIS)

Otsuka, N.; Semkova, V.; Simakov, S.P.; Zerkin, V.

2011-01-01

Dr Simakov of Nuclear Data Services Unit in the Nuclear Data Section (NDS) gave a brief overview of the data compilation and evaluation activities in the nuclear data community: experimental nuclear reaction data (EXFOR, http://www-nds.iaea.org/exfor/) and evaluated nuclear reaction data (ENDF, http://www-nds.iaea.org/endf). The International Network of Nuclear Reaction Data Centres (NRDC) coordinated by NDS includes 14 Centres in 8 Countries (China, Hungary, India, Japan, Korea, Russian, Ukraine, USA) and 2 International Organizations (NEA, IAEA). It had the first meeting of four core centres (Brookhaven, Saclay, Obninsk, Vienna) in 1966 and the EXFOR was adopted as an official data exchange format. In 2000, IAEA implemented the EXFOR database as a relational multiform database and the EXFOR is a trusted, increasing and living database with 19100 experimental works (as of September 2011) and 141600 data tables. The EXFOR provides a compilation control system for selection of articles and compilation of data and the NRDC home page provides manuals, documents and codes. The nuclear data can be retrieved by the web-retrieval system or distributed on a DVD on request. The EXFOR data play a critical role in the development of evaluated nuclear reaction data. There are several major general purpose libraries: ENDF (US), CENDL (China), JEFF (EU), JENDL (Japan) and RUSFOND (Russia). In addition, there are special libraries for particular applications: EAF (European Activation File), FENDL (Fusion Evaluated Nuclear Data Library for ITER neutronics), IBANDL (Ion Beam Analysis Nuclear Data Library for surface analysis of solids), IRDF, DXS (Dosimetry, radiation damage and gas production data) and Medical portal. Dr V. Zerkin of NDS demonstrated the data retrieval from the EXFOR database and the ENDF library.

Experimental (Network) and Evaluated Nuclear Reaction Data at NDS

Energy Technology Data Exchange (ETDEWEB)

Otsuka, N; Semkova, V; Simakov, S P; Zerkin, V [Nuclear Data Services Unit, Nuclear Data Section, IAEA, Vienna (Austria)

2011-11-15

Dr Simakov of Nuclear Data Services Unit in the Nuclear Data Section (NDS) gave a brief overview of the data compilation and evaluation activities in the nuclear data community: experimental nuclear reaction data (EXFOR, http://www-nds.iaea.org/exfor/) and evaluated nuclear reaction data (ENDF, http://www-nds.iaea.org/endf). The International Network of Nuclear Reaction Data Centres (NRDC) coordinated by NDS includes 14 Centres in 8 Countries (China, Hungary, India, Japan, Korea, Russian, Ukraine, USA) and 2 International Organizations (NEA, IAEA). It had the first meeting of four core centres (Brookhaven, Saclay, Obninsk, Vienna) in 1966 and the EXFOR was adopted as an official data exchange format. In 2000, IAEA implemented the EXFOR database as a relational multiform database and the EXFOR is a trusted, increasing and living database with 19100 experimental works (as of September 2011) and 141600 data tables. The EXFOR provides a compilation control system for selection of articles and compilation of data and the NRDC home page provides manuals, documents and codes. The nuclear data can be retrieved by the web-retrieval system or distributed on a DVD on request. The EXFOR data play a critical role in the development of evaluated nuclear reaction data. There are several major general purpose libraries: ENDF (US), CENDL (China), JEFF (EU), JENDL (Japan) and RUSFOND (Russia). In addition, there are special libraries for particular applications: EAF (European Activation File), FENDL (Fusion Evaluated Nuclear Data Library for ITER neutronics), IBANDL (Ion Beam Analysis Nuclear Data Library for surface analysis of solids), IRDF, DXS (Dosimetry, radiation damage and gas production data) and Medical portal. Dr V. Zerkin of NDS demonstrated the data retrieval from the EXFOR database and the ENDF library.

Nuclear Physics Division, Institute of Experimental Physics, Warsaw University Annual Report 1996

Energy Technology Data Exchange (ETDEWEB)

Szeflinski, Z.; Popkiewicz, M. [eds.

1997-12-31

In the presented report the research activities of Nuclear Physics Division (NPD) of the Institute of Experimental Physics (Warsaw University) in year 1996 are described. The report is divided into three parts: Reaction mechanisms and nuclear structure; Experimental methods and instrumentation and the third part contains the list of personnel, seminars held at the Nuclear Physics Division and published papers. A summary of the (NPD) activities are briefly presented in ``Preface`` by NPD director prof. Ch. Droste.

Nuclear Physics Division, Institute of Experimental Physics, Warsaw University annual report 1997

Energy Technology Data Exchange (ETDEWEB)

Szeflinski, Z.; Kirejczyk, M.; Popkiewicz, M. [eds.

1998-08-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Institute of Experimental Physics (Warsaw University) in year 1997 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contain the lists of personnel, seminars held at the Nuclear Physics Division and published papers. A summary of the (NPD) activities are briefly presented in ``Preface`` written by NDP director prof. K. Siwek-Wilczynska

Nuclear Physics Division, Institute of Experimental Physics, Warsaw University annual report 1997

International Nuclear Information System (INIS)

Szeflinski, Z.; Kirejczyk, M.; Popkiewicz, M.

1998-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Institute of Experimental Physics (Warsaw University) in year 1997 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contain the lists of personnel, seminars held at the Nuclear Physics Division and published papers. A summary of the (NPD) activities are briefly presented in ''Preface'' written by NDP director prof. K. Siwek-Wilczynska

Nuclear Physics Division, Institute of Experimental Physics, Warsaw University Annual Report 1996

International Nuclear Information System (INIS)

Szeflinski, Z.; Popkiewicz, M.

1997-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Institute of Experimental Physics (Warsaw University) in year 1996 are described. The report is divided into three parts: Reaction mechanisms and nuclear structure; Experimental methods and instrumentation and the third part contains the list of personnel, seminars held at the Nuclear Physics Division and published papers. A summary of the (NPD) activities are briefly presented in ''Preface'' by NPD director prof. Ch. Droste

'Level-level correlation and absorption in nuclear reactions'

International Nuclear Information System (INIS)

Hussein, M.S.

Level-level correlation (LLC) in nuclear reactions is discussed in general and it is shown that in the presence of LLC, N sub(μ) = Σ/g μa/ 2 > divided by gamma μ T tilde, where T tilde is the average absorption in the eigen channels [pt

Nuclear Physics Division - Inst. of Experimental Physics - Warsaw University - Annual Report 2003

International Nuclear Information System (INIS)

Kirejczyk, M.; Skwira, I.; Grodner, E.

2004-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Warsaw University Institute of Experimental Physics in year of 2003 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contain the lists of personnel, seminars held at the Nuclear Physics Division and list of published papers. A summary of the (NPD) activities are briefly presented in ''Preface'' written by NPD director prof. K. Siwek-Wilczynska

Nuclear Physics Division - Inst. of Experimental Physics - Warsaw University - Annual Report 1998

International Nuclear Information System (INIS)

Kirejczyk, M.; Szeflinski, Z.

1999-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Warsaw University Institute of Experimental Physics in year of 1998 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contains the lists of personnel, seminars held at the Nuclear Physics Division and list of published papers. A summary of the (NPD) activities are briefly presented in ''Preface'' written by NDP director prof. K. Siwek-Wilczynska

Nuclear Physics Division - Inst. of Experimental Physics - Warsaw University - Annual Report 2004

International Nuclear Information System (INIS)

Kirejczyk, M.K.

2005-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Warsaw University Institute of Experimental Physics in year of 2004 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contains the lists of personnel, seminars held at the Nuclear Physics Division and list of published papers. A summary of the (NPD) activities are briefly presented in ''Preface'' written by NDP director prof. K. Siwek-Wilczynska

Nuclear Physics Division - Inst. of Experimental Physics - Warsaw University - Annual Report 1998

Energy Technology Data Exchange (ETDEWEB)

Kirejczyk, M.; Szeflinski, Z. [eds.

1999-08-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Warsaw University Institute of Experimental Physics in year of 1998 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contains the lists of personnel, seminars held at the Nuclear Physics Division and list of published papers. A summary of the (NPD) activities are briefly presented in ``Preface`` written by NDP director prof. K. Siwek-Wilczynska

Nuclear Physics Division - Inst. of Experimental Physics - Warsaw University - Annual Report 2000

International Nuclear Information System (INIS)

Kirejczyk, M.

2001-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Warsaw University Institute of Experimental Physics in year of 2000 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contain the lists of personnel, seminars held at the Nuclear Physics Division and list of published papers. A summary of the (NPD) activities are briefly presented in 'Preface' written by NDP director prof. K. Siwek-Wilczynska

Nuclear Physics Division - Inst. of Experimental Physics - Warsaw University - Annual Report 2001

International Nuclear Information System (INIS)

Kirejczyk, M.

2001-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Warsaw University Institute of Experimental Physics in year of 2001 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one which contain the lists of personnel, seminars held at the Nuclear Physics Division and list of published papers. A summary of the (NPD) activities are briefly presented in ''Preface'' written by NPD director prof. K. Siwek-Wilczynska

Nuclear Physics Division - Inst. of Experimental Physics - Warsaw University - Annual Report 1999

International Nuclear Information System (INIS)

Kirejczyk, M.

2000-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Warsaw University Institute of Experimental Physics in year of 1999 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contain the lists of personnel, seminars held at the Nuclear Physics Division and list of published papers. A summary of the (NPD) activities are briefly presented in ''Preface'' written by NDP director prof. K. Siwek-Wilczynska

Development of anodic stripping voltametry for the determination of palladium in high level nuclear waste

Energy Technology Data Exchange (ETDEWEB)

Bhardwaj, T. K. [North Carolina State University, Raleigh (United States); Sharma, H. S.; Affarwal, S. K. [Bhabha Atomic Research Centre, Mumbai (India); Jain, P. C. [Meerut College, Meerut (India)

2012-12-15

Deposition potential, deposition time, square wave frequency, rotation speed of the rotating disc electrode, and palladium concentration were studied on a Glassy Carbon Electrode (GCE) in 0.01M HCl for the determination of palladium in High Level Nuclear Waste (HLNW) by anodic stripping voltammetry. Experimental conditions were optimized for the determination of palladium at two different, 10-8 and 10-7 M, levels. Error and standard deviation of this method were under 1% for all palladium standard solutions. The developed technique was successfully applied as a subsidiary method for the determination of palladium in simulated high level nuclear waste with very good precision and high accuracy (under 1 % error and standard deviation).

Using electrochemical separation to reduce the volume of high-level nuclear waste

International Nuclear Information System (INIS)

Slater, S.A.; Gay, E.C.

1998-01-01

Argonne National Laboratory (ANL) has developed an electrochemical separation technique called electrorefining that will treat a variety of metallic spent nuclear fuel and reduce the volume of high-level nuclear waste that requires disposal. As part of that effort, ANL has developed a high throughput electrorefiner (HTER) that has a transport rate approximately three times faster than electrorefiners previously developed at ANL. This higher rate is due to the higher electrode surface area, a shorter transport path, and more efficient mixing, which leads to smaller boundary layers about the electrodes. This higher throughput makes electrorefining an attractive option in treating Department of Energy spent nuclear fuels. Experiments have been done to characterize the HTER, and a simulant metallic fuel has been successfully treated. The HTER design and experimental results is discussed

Materials Science of High-Level Nuclear Waste Immobilization

International Nuclear Information System (INIS)

Weber, William J.; Navrotsky, Alexandra; Stefanovsky, S. V.; Vance, E. R.; Vernaz, Etienne Y.

2009-01-01

With the increasing demand for the development of more nuclear power comes the responsibility to address the technical challenges of immobilizing high-level nuclear wastes in stable solid forms for interim storage or disposition in geologic repositories. The immobilization of high-level nuclear wastes has been an active area of research and development for over 50 years. Borosilicate glasses and complex ceramic composites have been developed to meet many technical challenges and current needs, although regulatory issues, which vary widely from country to country, have yet to be resolved. Cooperative international programs to develop advanced proliferation-resistant nuclear technologies to close the nuclear fuel cycle and increase the efficiency of nuclear energy production might create new separation waste streams that could demand new concepts and materials for nuclear waste immobilization. This article reviews the current state-of-the-art understanding regarding the materials science of glasses and ceramics for the immobilization of high-level nuclear waste and excess nuclear materials and discusses approaches to address new waste streams

Determination of the nuclear level densities and radiative strength function for 43 nuclei in the mass interval 28≤A≤200

Science.gov (United States)

Knezevic, David; Jovancevic, Nikola; Sukhovoj, Anatoly M.; Mitsyna, Ludmila V.; Krmar, Miodrag; Cong, Vu D.; Hambsch, Franz-Josef; Oberstedt, Stephan; Revay, Zsolt; Stieghorst, Christian; Dragic, Aleksandar

2018-03-01

The determination of nuclear level densities and radiative strength functions is one of the most important tasks in low-energy nuclear physics. Accurate experimental values of these parameters are critical for the study of the fundamental properties of nuclear structure. The step-like structure in the dependence of the level densities p on the excitation energy of nuclei Eex is observed in the two-step gamma cascade measurements for nuclei in the 28 ≤ A ≤ 200 mass region. This characteristic structure can be explained only if a co-existence of quasi-particles and phonons, as well as their interaction in a nucleus, are taken into account in the process of gamma-decay. Here we present a new improvement to the Dubna practical model for the determination of nuclear level densities and radiative strength functions. The new practical model guarantees a good description of the available intensities of the two step gamma cascades, comparable to the experimental data accuracy.

Proceedings of the Jorge Andre Swieca Summer School; 4. Experimental Nuclear Physics Session

International Nuclear Information System (INIS)

1990-01-01

These proceedings present works on experimental nuclear physics, activation analysis, nuclear interactions, neutron physics, nuclear moments, inelastic scattering, lattices and chemical analysis. (L.C.J.A.)

Experimental physics 4. Nuclear, particle and astrophysics. 5. ed.; Experimentalphysik 4. Kern-, Teilchen- und Astrophysik

Energy Technology Data Exchange (ETDEWEB)

Demtroeder, Wolfgang

2017-09-01

The following topics are dealt with: Structure of atomic nuclei, unstable nuclei and radioactivity, experimental techniques in nuclear and high-energy physics, nuclear forces and nuclear models, nuclear reactions, physics of elementary particles, applications of nuclear and high-energy physics, foundations of experimental astronomy and astrophysics, our solar system, birth, life, and death of stars, the development and present structure of the universe. (HSI)

Statistical interpretation of low energy nuclear level schemes

Energy Technology Data Exchange (ETDEWEB)

Egidy, T von; Schmidt, H H; Behkami, A N

1988-01-01

Nuclear level schemes and neutron resonance spacings yield information on level densities and level spacing distributions. A total of 75 nuclear level schemes with 1761 levels and known spins and parities was investigated. The A-dependence of level density parameters is discussed. The spacing distributions of levels near the groundstate indicate transitional character between regular and chaotic properties while chaos dominates near the neutron binding energy.

Experimental study of water flow in nuclear fuel elements; Estudo experimental do escoamento de agua em elementos combustiveis nucleares

Energy Technology Data Exchange (ETDEWEB)

Rodrigues, Lorena Escriche, E-mail: ler@cdtn.br [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET), Belo Horizonte, MG (Brazil); Rezende, Hugo Cesar; Mattos, Joao Roberto Loureiro de; Barros Filho, Jose Afonso; Santos, Andre Augusto Campagnole dos, E-mail: hcr@cdtn.br, E-mail: jrmattos@cdtn.br, E-mail: jabf@cdtn.br, E-mail: aacs@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2013-07-01

This work aims to develop an experimental methodology for investigating the water flow through rod bundles after spacer grids of nuclear fuel elements of PWR type reactors. Speed profiles, with the device LDV (Laser Doppler Velocimetry), and the pressure drop between two sockets located before and after the spacer grid, using pressure transducers were measured.

Progress of experimental research on nuclear safety in NPIC

Energy Technology Data Exchange (ETDEWEB)

Gong, Houjun; Zan, Yuanfeng; Peng, Chuanxin; Xi, Zhao; Zhang, Zhen; Wang, Ying; He, Yanqiu; Huang, Yanping [Nuclear Power Institute of China, Chengdu (China)

2016-05-15

Two kinds of Generation III commercial nuclear power plants have been developed in CNNC (China National Nuclear Corporation), one is a small modular reactor ACP100 having an equivalent electric power 100 MW, and the other is HPR1000 (once named ACP1000) having an equivalent electric power 1 000 MW. Both NPPs widely adopted the design philosophy of advanced passive safety systems and considered the lessons from Fukushima Daichi nuclear accident. As the backbone of the R and D of ACP100 and HPR1000, NPIC (Nuclear power Institute of China) has finished the engineering verification test of main safety systems, including passive residual heat removal experiments, reactor cavity injection experiments, hydrogen combustion experiments, and passive autocatalytic recombiner experiments. Above experimental work conducted in NPIC and further research plan of nuclear safety are introduced in this paper.

Storage of High Level Nuclear Waste in Germany

Directory of Open Access Journals (Sweden)

Dietmar P. F. Möller

2007-01-01

Full Text Available Nuclear energy is very often used to generate electricity. But first the energy must be released from atoms what can be done in two ways: nuclear fusion and nuclear fission. Nuclear power plants use nuclear fission to produce electrical energy. The electrical energy generated in nuclear power plants does not produce polluting combustion gases but a renewable energy, an important fact that could play a key role helping to reduce global greenhouse gas emissions and tackling global warming especially as the electricity energy demand rises in the years ahead. This could be assumed as an ideal win-win situation, but the reverse site of the medal is that the production of high-level nuclear waste outweighs this advantage. Hence the paper attempt to highlight the possible state-of-art concepts for the safe and sustaining storage of high-level nuclear waste in Germany.

Experimental Nuclear Physics Activity in Italy

Science.gov (United States)

Chiavassa, E.; de Marco, N.

2003-04-01

The experimental Nuclear Physics activity of the Italian researchers is briefly reviewed. The experiments, that are financially supported by the INFN, are done in strict collaboration by more than 500 INFN and University researchers. The experiments cover all the most important field of the modern Nuclear Physics with probes extremely different in energy and interactions. Researches are done in all the four National Laboratories of the INFN even if there is a deeper involvement of the two national laboratories expressly dedicated to Nuclear Physics: the LNL (Laboratorio Nazionale di Legnaro) and LNS (Laboratorio Nazionale del Sud) where nuclear spectroscopy and reaction dynamics are investigated. All the activities with electromagnetic probes develops in abroad laboratories as TJNAF, DESY, MAMI, ESFR and are dedicated to the studies of the spin physics and of the nucleon resonance; hypernuclear and kaon physics is investigated at LNF. A strong community of researchers work in the relativistic and ultra-relativistic heavy ions field in particular at CERN with the SPS Pb beam and in the construction of the ALICE detector for heavy-ion physics at the LHC collider. Experiments of astrophysical interest are done with ions of very low energy; in particular the LUNA accelerator facility at LNGS (Laboratorio Nazionale del Gran Sasso) succeeded measuring cross section at solar energies, below or near the solar Gamow peak. Interdisciplinary researches on anti-hydrogen atom spectroscopy and on measurements of neutron cross sections of interest for ADS development are also supported.

Water level monitoring device in nuclear reactor

International Nuclear Information System (INIS)

Miura, Kiyohide; Otake, Tomohiro.

1988-01-01

Purpose: To monitor the water level in a pressure vessel of BWR type nuclear reactors at high accuracy by improving the compensation functions. Constitution: In the conventional water level monitor in a nuclear reactor, if the pressure vessel is displaced by the change of the pressure in the reactor or the temperature of the reactor water, the relative level of the reference water head in a condensation vessel is changed to cause deviation between the actual water level and the indicated water level to reduce the monitoring accuracy. According to the invention, means for detecting the position of the reference water head and means for detection the position in the condensation vessel are disposed to the pressure vessel. Then, relative positional change between the condensation vessel and the reference water head is calculated based on detection sinals from both of the means. The water level is compensated and calculated by water level calculation means based on the relative positional change, water level signals from the level gage and the pressure signals from the pressure gage. As a result, if the pressure vessel is displaced due to the change of the temperature or pressure, it is possible to measure the reactor water level accurately thereby remakably improve the reliability for the water level control in the nuclear reactor. (Horiuchi, T.)

Experimental Investigation of Burnup Credit for Safe Transport, Storage, and Disposal of Spent Nuclear Fuel

International Nuclear Information System (INIS)

Harms, Gary A.; Helmick, Paul H.; Ford, John T.; Walker, Sharon A.; Berry, Donald T.; Pickard, Paul S.

2004-01-01

This report describes criticality benchmark experiments containing rhodium that were conducted as part of a Department of Energy Nuclear Energy Research Initiative project. Rhodium is an important fission product absorber. A capability to perform critical experiments with low-enriched uranium fuel was established as part of the project. Ten critical experiments, some containing rhodium and others without, were conducted. The experiments were performed in such a way that the effects of the rhodium could be accurately isolated. The use of the experimental results to test neutronics codes is demonstrated by example for two Monte Carlo codes. These comparisons indicate that the codes predict the behavior of the rhodium in the critical systems within the experimental uncertainties. The results from this project, coupled with the results of follow-on experiments that investigate other fission products, can be used to quantify and reduce the conservatism of spent nuclear fuel safety analyses while still providing the necessary level of safety

Thermodynamics of excited nuclei and nuclear level densities

International Nuclear Information System (INIS)

Ramamurthy, V.S.

1977-01-01

A review has been made of the different approaches that are being used for a theoretical calculation of nuclear level densities. It is pointed out that while the numerical calculations based on the partition function approach and shell model single particle level schemes have shed important insight into the influence of nuclear shell effects on level densities and its excitation energy dependence and have brought out the inadequacy of the conventional Bethe Formula, these calculations are yet to reach a level where they can be directly used for quantitative comparisons. Some of the important drawbacks of the numerical calculations are also discussed. In this context, a new semi-empirical level density formula is described which while retaining the simplicity of analytical formulae, takes into account nuclear shell effects in a more realistic manner. (author)

Liquid level measurement in high level nuclear waste slurries

International Nuclear Information System (INIS)

Weeks, G.E.; Heckendorn, F.M.; Postles, R.L.

1990-01-01

Accurate liquid level measurement has been a difficult problem to solve for the Defense Waste Processing Facility (DWPF). The nuclear waste sludge tends to plug or degrade most commercially available liquid-level measurement sensors. A liquid-level measurement system that meets demanding accuracy requirements for the DWPF has been developed. The system uses a pneumatic 1:1 pressure repeater as a sensor and a computerized error correction system. 2 figs

Study of nuclear level density parameter and its temperature dependence

International Nuclear Information System (INIS)

Nasrabadi, M. N.; Behkami, A. N.

2000-01-01

The nuclear level density ρ is the basic ingredient required for theoretical studies of nuclear reaction and structure. It describes the statistical nuclear properties and is expressed as a function of various constants of motion such as number of particles, excitation energy and angular momentum. In this work the energy and spin dependence of nuclear level density will be presented and discussed. In addition the level density parameter α will be extracted from this level density information, and its temperature and mass dependence will be obtained

Effect of pairing in nuclear level density at low temperatures

International Nuclear Information System (INIS)

Rhine Kumar, A.K.; Modi, Swati; Arumugam, P.

2013-01-01

The nuclear level density (NLD) has been an interesting topic for researchers, due its importance in many aspects of nuclear physics, nuclear astrophysics, nuclear medicine, and other applied areas. The calculation of NLD helps us to understand the energy distribution of the excited levels of nuclei, entropy, specific heat, reaction cross sections etc. In this work the effect of temperature and pairing on level-density of the nucleus 116 Sn has been studied

ZZ-CENPL, Chinese Evaluated Nuclear Parameter Library. ZZ CENPL-DLS, Discrete Level Schemes and Gamma Branching Ratios Library; ZZ CENPL-FBP, Fission Barrier Parameter Library; ZZ CENPL-GDRP, Giant Dipole Resonance Parameter Library; ZZ CENPL-NLD, Nuclear Level Density Parameter Library; ZZ CENPL-MCC, Nuclear Ground State Atomic Masses Library; ZZ CENPL-OMP, Optical Model Parameter Library

International Nuclear Information System (INIS)

Su Zongdi

1995-01-01

Description of program or function: CENPL - GDRP (Giant Dipole Resonance Parameters for Gamma-Ray): - Format: special format described in documentation; - Nuclides: V, Mn, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Rb, Sr, Y, Zr, Nb, Mo, Rh, Pd, Ag, Cd, In, Sn, Sb, Te, I, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Ho, Er, Lu, Ta, W, Re, Os, Ir, Pt, Au, Hg, Pb, Bi, Th, U, Np, Pu. - Origin: Experimental values offered by S.S. Dietrich and B.L. Berman. CENPL - FBP (Fission Barrier Parameter Sub-Library): - Format: special format described in documentation; - Nuclides: (1) 51 nuclei region from Th-230 to Cf-255, (2) 46 nuclei region from Th-229 to Cf-253, (3) 24 nuclei region from Pa-232 to Cf-253; - Origin: (1) Lynn, (2) Analysis of experimental data by Back et al., (3) Ohsawa. CENPL - DLS (Discrete level scheme and branch ratio of gamma decay: - Format: Special format described in documentation; - Origin: ENSDF - BNL. CENPL - NLD (Nuclear Level Density): - Format: Special format described in documentation; - Origin: Huang Zhongfu et al. CENPL - OMP (Optical model parameter sub-library): - Format: special format described in documentation ; - Origin: CENDL, ENDF/B-VI, JENDL-3. CENPL - MC (I) and (II) (Atomic masses and characteristic constants for nuclear ground states) : - Format: Brief table format; - Nuclides: 4760 nuclides ranging from Z=0 A=1 to Z=122 A=318. - Origin: Experimental data and systematic results evaluated by Wapstra, theoretical results calculated by Moller, ENSDF - BNL and Nuclear Wallet Cards. CENPL contains the following six sub-libraries: 1. Atomic Masses and Characteristic Constants for nuclear ground states (MCC). This data consists of calculated and in most cases also measured mass excesses, atomic masses, total binding energies, spins, parities, and half-lives of nuclear ground states, abundances, etc. for 4800 nuclides. 2. Discrete Level Schemes and branching ratios of gamma decay (DLS). The data on nuclear discrete levels are based on the Evaluated

Nuclear level densities with pairing and self-consistent ground-state shell effects

CERN Document Server

Arnould, M

1981-01-01

Nuclear level density calculations are performed using a model of fermions interacting via the pairing force, and a realistic single particle potential. The pairing interaction is treated within the BCS approximation with different pairing strength values. The single particle potentials are derived in the framework of an energy-density formalism which describes self-consistently the ground states of spherical nuclei. These calculations are extended to statistically deformed nuclei, whose estimated level densities include rotational band contributions. The theoretical results are compared with various experimental data. In addition, the level densities for several nuclei far from stability are compared with the predictions of a back-shifted Fermi gas model. Such a comparison emphasizes the possible danger of extrapolating to unknown nuclei classical level density formulae whose parameter values are tailored for known nuclei. (41 refs).

Comprehensive data base of high-level nuclear waste glasses: September 1987 status report: Volume 1, Discussion and glass durability data

International Nuclear Information System (INIS)

Kindle, C.H.; Kreiter, M.R.

1987-12-01

The Materials Characterization Center (MCC) at Pacific Northwest Laboratory is assembling a comprehensive data base (CDB) of experimental data collected for high-level nuclear waste package components. Data collected throughout the world are included in the data base; current emphasis is on waste glasses and their properties. The goal is to provide a data base of properties and compositions and an analysis of dominant property trends as a function of composition. This data base is a resource that nuclear waste producers, disposers, and regulators can use to compare properties of a particular high-level nuclear waste glass product with the properties of other glasses of similar compositions. Researchers may use the data base to guide experimental tests to fill gaps in the available knowledge or to refine empirical models. The data are incorporated into a computerized data base that will allow the data to be extracted based on, for example, glass composition or test duration. 3 figs

Nuclear moment of inertia and spin distribution of nuclear levels

International Nuclear Information System (INIS)

Alhassid, Y.; Fang, L.; Liu, S.; Bertsch, G.F.

2005-01-01

We introduce a simple model to calculate the nuclear moment of inertia at finite temperature. This moment of inertia describes the spin distribution of nuclear levels in the framework of the spin-cutoff model. Our model is based on a deformed single-particle Hamiltonian with pairing interaction and takes into account fluctuations in the pairing gap. We derive a formula for the moment of inertia at finite temperature that generalizes the Belyaev formula for zero temperature. We show that a number-parity projection explains the strong odd-even effects observed in shell model Monte Carlo studies of the nuclear moment of inertia in the iron region

Experimental Study of Nuclear Security System Components for Achieving the Intrusion Process via Sensor's Network System

International Nuclear Information System (INIS)

EL-Kafas, A.A.

2011-01-01

Cluster sensors are one of nuclear security system components which are used to detect any intrusion process of the nuclear sites. In this work, an experimental measuring test for sensor performance and procedures are presented. Sensor performance testing performed to determine whether a particular sensor will be acceptable in a proposed design. We have access to a sensors test field in which the sensor of interest is already properly installed and the parameters have been set to optimal levels by preliminary testing. The glass-breakage (G.B) and open door (O.D) sensors construction, operation and design for the investigated nuclear site are explained. Intrusion tests were carried out inside the field areas of the sensors to evaluate the sensor performance during the intrusion process. Experimental trials were performed for achieving the intrusion process via sensor network system. The performance and intrusion senses of cluster sensors inside the internal zones was recorded and evaluated. The obtained results explained that the tested and experimented G.B sensors have a probability of detection P (D) value 65% founded, and 80% P (D) of Open-door sensor

Management of the high-level nuclear power facilities

International Nuclear Information System (INIS)

Preda, Marin

2003-05-01

This thesis approaches current issues in the management of the high power nuclear facilities and as such it appears to be important particularly for nuclear power plant operation topics. Of special interest are the failure events entailing possible catastrophic situations. The contents is structured onto ten chapters. The first chapter describes the operation regimes of the nuclear high power facilities. Highlighted here are the thesis scope and the original features of the work. The second chapter deals with operational policies developed in order to ensure the preventive maintenance of the nuclear installations. Also managing structures are described devoted to practical warranting the equipment safety function of non-classical power stations. In the third chapter cases of nuclear accidents are analyzed especially stressing the probabilistic risk and the operation regimes having in view the elimination of catastrophic events. In the fourth and fifth chapters the control of nuclear radiation emission is treated focusing the quality issue of nuclear installations required to avoid hazardous effects at level of nuclear reactor operation stage. At the same time set of operational measures is given here for preventing risks, catastrophes and chaotic situations. The chapter five presents both theoretical and practical approaches of the nuclear reactor core management concerning particularly the fuel testing, the water primary system and the quality of the involved equipment. In the sixth and seventh chapters issues of risk-quality correlations are approached as well as the structure of expert systems for monitoring the operational regimes of nuclear facilities. The efficiency of the power systems with nuclear injection is discussed and some original ideas developed in this work are evidenced in the eighth and ninth chapters. Presented are here both the operational principles and models of raising the efficiency of the interconnected nuclear stations and prices' policy

Establishment of Experimental Equipment for Training of Professionals in the Nuclear Radiation Measurement

Energy Technology Data Exchange (ETDEWEB)

Ahn, S. K.; Seo, K. W.; Joo, Y. C.; Kim, I. C.; Woo, C. K.; Yoo, B. H. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2008-09-15

The main purpose of this project is to establish experimental equipment for training of professionals and students in the field of radiation measurement, and settle the foundation for the advanced education system and program. The priority for the experimental equipment had been deduced by reviewing of the Nuclear Training and Education Center of KAERI and other country's training courses. Equipment for training of radiation professionals are High-Purity Germanium spectroscopic systems, alpha analyzers, and hand-held gamma/neutron inspector systems. For the basic experiments, electric personal dosimeters and a reader, radiation survey meters, and various alpha, beta and gamma radiation isotopes have been equipped. Some old or disused equipment and devices were disposed and re-arranged, and a new experiment lab had been settled for gamma spectroscopy. Along with the preparation of equipment, 14 experimental modules have been selected for practical and essential experiments training to professionals from industries, universities and research organizations. Among the modules, 7 important experiment notes had been prepared in Korea and also in English. As a consequence, these advanced radiation experimental setting would be a basis to cooperate with IAEA or other countries for international training courses. These activities would be a foundation for our contribution to the international nuclear society and for improving our nuclear competitiveness. The experimental equipment and application notes developed in this study will be used also by other training institutes and educational organizations through introducing and encouraging to use them to the nuclear society.

Establishment of Experimental Equipment for Training of Professionals in the Nuclear Radiation Measurement

International Nuclear Information System (INIS)

Ahn, S. K.; Seo, K. W.; Joo, Y. C.; Kim, I. C.; Woo, C. K.; Yoo, B. H.

2008-09-01

The main purpose of this project is to establish experimental equipment for training of professionals and students in the field of radiation measurement, and settle the foundation for the advanced education system and program. The priority for the experimental equipment had been deduced by reviewing of the Nuclear Training and Education Center of KAERI and other country's training courses. Equipment for training of radiation professionals are High-Purity Germanium spectroscopic systems, alpha analyzers, and hand-held gamma/neutron inspector systems. For the basic experiments, electric personal dosimeters and a reader, radiation survey meters, and various alpha, beta and gamma radiation isotopes have been equipped. Some old or disused equipment and devices were disposed and re-arranged, and a new experiment lab had been settled for gamma spectroscopy. Along with the preparation of equipment, 14 experimental modules have been selected for practical and essential experiments training to professionals from industries, universities and research organizations. Among the modules, 7 important experiment notes had been prepared in Korea and also in English. As a consequence, these advanced radiation experimental setting would be a basis to cooperate with IAEA or other countries for international training courses. These activities would be a foundation for our contribution to the international nuclear society and for improving our nuclear competitiveness. The experimental equipment and application notes developed in this study will be used also by other training institutes and educational organizations through introducing and encouraging to use them to the nuclear society

Shell Effect and Temperature Influence on Nuclear Level Density Parameter: the role of the effective mass interaction

International Nuclear Information System (INIS)

Queipo-Ruiz, J.; Guzman-Martinez, F.; Rodriguez-Hoyos, O.

2011-01-01

The level density parameter is a very important ingredient in statistic study of nuclear reaction, it has been studied to low energies excitation E < 2MeV where it values is approximately constant, experimental results to energies of excitation more than 2 MeV has been obtained of evaporation spectrum, to nuclei with A=160. In this work we present a calculation of densities level parameter, for a wide range of mass and temperature, taking in accounts the shell effects and the mass effective interaction. The result has been carried out within the semi classical approximation, for the single particle level densities. We results have a reasonable agreement with the experimental data available. (Author)

Examination of State-Level Nuclear Security Evaluation Methods

International Nuclear Information System (INIS)

Kim, Chan Kim; Yim, Man-Sung

2015-01-01

An effective global system for nuclear materials security needs to cover all materials, employing international standards and best practices, to reduce risks by reducing weapons-usable nuclear material stocks and the number of locations where they are found. Such a system must also encourage states to accept peer reviews by outside experts in order to demonstrate that effective security is in place. It is thus critically important to perform state-level evaluation of nuclear security based on an integrative framework of risk assessment. Such evaluation provides a basis of measuring the level and progress of international effort to secure and control all nuclear materials. sensitivity test by differentiating weight factors of each of the indicators and categories will be performed in the future as well

Completion of the experimental equipment systems and preparation of practical tutorials on the Dalat Nuclear Research Reactor for nuclear science and technology education

International Nuclear Information System (INIS)

Le Vinh Vinh; Huynh Ton Nghiem; Luong Ba Vien; Nguyen Minh Tuan; Nguyen Kien Cuong; Pham Quang Huy; Tran Tri Vien

2015-01-01

The project Completion of the experimental equipment systems and preparation of practical tutorials on the Dalat Nuclear Research Reactor for nuclear science and technology education performed by Dalat Nuclear Research Institute and financed by Ministry of Science and Technology aimed at strengthening the training capability of nuclear human resources. The content of this work includes: i) Improvement of experimental equipment; ii) Compilation of training material for experiments with the improved equipment systems on the reactor; iii) Compilation of training material for reactor calculations includes the following areas: neutronics, hydrothermal, safety analysis and accident consequence analysis. Results of the project provide important conditions to support practical educational and training curriculums in nuclear science and technology. (author)

Overview of experimental research on nuclear structure in department of modern applied physics

International Nuclear Information System (INIS)

Zhu Shengjiang

1999-01-01

The experimental research on nuclear structure in Department of Modern Applied Physics, Tsinghua University has been summarized. The main research results in high spin states of nuclear structure, as well as some low spin states, have been reported

Experimental observations on electrorefining spent nuclear fuel in molten LiCl-KCl/liquid cadmium system

International Nuclear Information System (INIS)

Johnson, T. A.; Laug, D. V.; Li, S. X.; Sofu, T.

1999-01-01

Argonne National Laboratory (ANL) is currently performing a demonstration program for the Department of Energy (DOE) which processes spent nuclear fuel from the Experimental Breeder Reactor (EBR-II). One of the key steps in this demonstration program is electrorefining of the spent fuel in a molten LiCl-KCl/liquid cadmium system using a pilot scale electrorefiner (Mk-IV ER). This article summarizes experimental observations and engineering aspects for electrorefining spent fuel in the molten LiCl-KCl/liquid cadmium system. It was found that the liquid cadmium pool acted as an intermediate electrode during the electrorefining process in the ER. The cadmium level was gradually decreased due to its high vapor pressure and vaporization rate at the ER operational temperature. The low cadmium level caused the anode assembly momentarily to touch the ER vessel hardware, which generated a periodic current change at the salt/cathode interface and improved uranium recovery efficiency for the process. The primary current distributions calculated by numerical simulations were used in interpreting the experimental results

Two-level convolution formula for nuclear structure function

Science.gov (United States)

Ma, Boqiang

1990-05-01

A two-level convolution formula for the nuclear structure function is derived in considering the nucleus as a composite system of baryon-mesons which are also composite systems of quark-gluons again. The results show that the European Muon Colaboration effect can not be explained by the nuclear effects as nucleon Fermi motion and nuclear binding contributions.

Two-level convolution formula for nuclear structure function

International Nuclear Information System (INIS)

Ma Boqiang

1990-01-01

A two-level convolution formula for the nuclear structure function is derived in considering the nucleus as a composite system of baryon-mesons which are also composite systems of quark-gluons again. The results show that the European Muon Colaboration effect can not be explained by the nuclear effects as nucleon Fermi motion and nuclear binding contributions

Nuclear Physics Division Institute of Experimental Physics Warsaw University annual report 1994

Energy Technology Data Exchange (ETDEWEB)

Osuch, S. [ed.

1995-12-31

In the presented Annual Report the activities of the Nuclear Physics Division of the Institute of Experimental Physics of the Warsaw University in 1994 are described. The report consist of three sections: (i) Reaction Mechanism and Nuclear Structure (12 articles); (ii) Experimental Methods and Instrumentation (2 articles); (iii) Other Research (1 article). Additionally the list of seminars held at the NPD, personnel list and list of published papers is also given. In the first, leading article of the report written by head of NPD prof. Ch. Droste the general description of the Department activity is presented.

Nuclear Physics Division Institute of Experimental Physics Warsaw University annual report 1994

International Nuclear Information System (INIS)

Osuch, S.

1995-01-01

In the presented Annual Report the activities of the Nuclear Physics Division of the Institute of Experimental Physics of the Warsaw University in 1994 are described. The report consist of three sections: i) Reaction Mechanism and Nuclear Structure (12 articles); ii) Experimental Methods and Instrumentation (2 articles); iii) Other Research (1 article). Additionally the list of seminars held at the NPD, personnel list and list of published papers is also given. In the first, leading article of the report written by head of NPD prof. Ch. Droste the general description of the Department activity is presented

Optimizing Nuclear Reaction Analysis (NRA) using Bayesian Experimental Design

International Nuclear Information System (INIS)

Toussaint, Udo von; Schwarz-Selinger, Thomas; Gori, Silvio

2008-01-01

Nuclear Reaction Analysis with 3 He holds the promise to measure Deuterium depth profiles up to large depths. However, the extraction of the depth profile from the measured data is an ill-posed inversion problem. Here we demonstrate how Bayesian Experimental Design can be used to optimize the number of measurements as well as the measurement energies to maximize the information gain. Comparison of the inversion properties of the optimized design with standard settings reveals huge possible gains. Application of the posterior sampling method allows to optimize the experimental settings interactively during the measurement process.

The former experimental nuclear power station in Lucens

International Nuclear Information System (INIS)

Meichle, A.

1989-01-01

In June 1989 in the Swiss canton of Vaud, a majority vote was reached for the discharge from federal responsibility and control of the experimental reactor in Lucens, which was shut down following an accident twenty years ago. As the topic 'Lucens' will remain current interest for some time, a brief history as well as future prospects are presented. The report begins with Switzerland's immediate post-war recognition of the importance of nuclear energy. This was initially characterized by the formation of Reactor Ltd., and three commercial groups. The submission of projects by the latter to parliament in the 1950's for the construction of a test nuclear reactor with the request for federal support met with a positive echo and a subsidy of 50% of the costs. The NGA (a national society for the promotion of industrial nuclear technology) was founded with the aim to consolidate projects into a national plan. The NGA's first step was to plan and install an experimental, heavy water moderated, gas-cooled reactor in Lucens. An engineering group (AGL) was delegated by the NGA to plan, construct and commission the reactor. The construction began in July 1962. The location, type of reactor, fuel used, cooling system and the placement in 3 cavities in a hill are briefly described. In 1966 the reactor first went critical and 2 years later 30 MW thermal power was attained. The construction engineers and the operating management were completely satisfied with reactor operation prior to the accident. 1 fig

Progress on Plant-Level Components for Nuclear Fuel Recycling: Commonality

International Nuclear Information System (INIS)

De Almeida, Valmor F.

2011-01-01

considering these activities. The exploitation of mathematical commonality for unit operations with the intent of developing generic and comprehensive software for nuclear reprocessing has not been considered to this author's knowledge. Past attention has been given to plant-level processes on an individual and isolated basis, which has led to various models and corresponding codes implementing non-systematic approaches based on elementary principles of chemical processing. This practice has built an initial knowledge base, but it was not fruitful in producing a lasting and extensible simulation capability. In contrast, a common, rigorous, mathematical modeling framework for all plant-level operations, as proposed here, has a tremendous practical and theoretical value because it will reduce the software implementation work, creates a well-defined modeling standard to compare past and future models, and, more importantly, opens the doors for scientific considerations of simulation fidelity; the latter has an obvious beneficial impact in supporting experimental validation programs. Therefore, the proposed framework is likely to generate a solid foundation for modeling plant-level processes for physicochemical nuclear (and non-nuclear) applications. Demonstration of concrete module implementation is the subject of future communications including prototypes for several modules, namely, voloxidation, dissolver, digester, accountability tank, and solvent extraction. Unit-operation commonality is a key aspect to be explored for a successful implementation of these modules aimed at realizing various flowsheets and plant configurations.

Progress on Plant-Level Components for Nuclear Fuel Recycling: Commonality

Energy Technology Data Exchange (ETDEWEB)

de Almeida, Valmor F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2011-08-15

considering these activities. The exploitation of mathematical commonality for unit operations with the intent of developing generic and comprehensive software for nuclear reprocessing has not been considered to this author's knowledge. Past attention has been given to plant-level processes on an individual and isolated basis, which has led to various models and corresponding codes implementing non-systematic approaches based on elementary principles of chemical processing. This practice has built an initial knowledge base, but it was not fruitful in producing a lasting and extensible simulation capability. In contrast, a common, rigorous, mathematical modeling framework for all plant-level operations, as proposed here, has a tremendous practical and theoretical value because it will reduce the software implementation work, creates a well-defined modeling standard to compare past and future models, and, more importantly, opens the doors for scientific considerations of simulation fidelity; the latter has an obvious beneficial impact in supporting experimental validation programs. Therefore, the proposed framework is likely to generate a solid foundation for modeling plant-level processes for physicochemical nuclear (and non-nuclear) applications. Demonstration of concrete module implementation is the subject of future communications including prototypes for several modules, namely, voloxidation, dissolver, digester, accountability tank, and solvent extraction. Unit-operation commonality is a key aspect to be explored for a successful implementation of these modules aimed at realizing various flowsheets and plant configurations.

Influence of operation of national experimental nuclear reactor on the natural environment

Directory of Open Access Journals (Sweden)

Agnieszka Kaczmarek-Kacprzak

2012-09-01

Full Text Available This paper presents the impact of experimental nuclear reactor operations on the national environment, based on assessment reports of the radiological protection of active nuclear technology sources. Using the analysis of measurements carried out in the last 15 years, the trends are presented in selected elements of the environment on the Świerk Nuclear Centre site and its surroundings. In addition, the impact of research results is presented from the fi fteen year period of environmental analysis on building public confi dence on the eve of the start of construction of the first Polish nuclear power plant.

Experimental study of water flow in nuclear fuel elements

International Nuclear Information System (INIS)

Rodrigues, Lorena Escriche; Rezende, Hugo Cesar; Mattos, Joao Roberto Loureiro de; Barros Filho, Jose Afonso; Santos, Andre Augusto Campagnole dos

2013-01-01

This work aims to develop an experimental methodology for investigating the water flow through rod bundles after spacer grids of nuclear fuel elements of PWR type reactors. Speed profiles, with the device LDV (Laser Doppler Velocimetry), and the pressure drop between two sockets located before and after the spacer grid, using pressure transducers were measured

Existing experimental criticality data applicable to nuclear-fuel-transportation systems

International Nuclear Information System (INIS)

Bierman, S.R.

1983-02-01

Analytical techniques are generally relied upon in making criticality evaluations involving nuclear material outside reactors. For these evaluations to be accepted the calculations must be validated by comparison with experimental data for a known set of conditions having physical and neutronic characteristics similar to those conditions being evaluated analytically. The purpose of this report is to identify those existing experimental data that are suitable for use in verifying criticality calculations on nuclear fuel transportation systems. In addition, near term needs for additional data in this area are identified. Of the considerable amount of criticality data currently existing, that are applicable to non-reactor systems, those particularly suitable for use in support of nuclear material transportation systems have been identified and catalogued into the following groups: (1) critical assemblies of fuel rods in water; (2) critical assemblies of fuel rods in water containing soluble neutron absorbers; (3) critical assemblies containing solid neutron absorber; (4) critical assemblies of fuel rods in water with heavy metal reflectors; and (5) critical assemblies of fuel rods in water with irregular features. A listing of the current near term needs for additional data in each of the groups has been developed for future use in planning criticality research in support of nuclear fuel transportation systems. The criticality experiments needed to provide these data are briefly described and identified according to priority and relative cost of performing the experiments

Recent advances in measurements of the nuclear level density

International Nuclear Information System (INIS)

John, Bency

2007-01-01

A short review of recent advances in measurements of the nuclear level density is given. First results of the inverse level density parameter - angular momentum correlation in a number of nuclei around Z∼50 shell region at an excitation energy around 0.3 MeV/nucleon are presented. Significant variations observed over and above the expected shell corrections are discussed in context of the emerging trends in microscopic calculations of the nuclear level density. (author)

A novel experimental technique of nuclear lifetime measurements

International Nuclear Information System (INIS)

Yuminov, O.A.; D'Arrigo, A.; Giardina, G.; Taccone, A.; Vannini, G.; Moroni, A.; Ricci, R.A.; Vannucci, L.

1995-01-01

In the present paper a new experimental method to measure nuclear reaction time in the 10 -15 -10 -10 s region is presented. Measurements of the lifetimes of low-lying and long-lived states of 19 F and 20 Ne decaying via α-channel were carried out with the aim of checking the feasibility of the method. The results obtained in this way are compared with the lifetimes known from different techniques. ((orig.))

Experimental nuclear medicine

Energy Technology Data Exchange (ETDEWEB)

Dormehl, I C [Nuclear Development Corp. of South Africa (Pty.) Ltd., Pelindaba, Pretoria. Inst. of Life Sciences; Du Plessis, M; Jacobs, D J

1983-07-01

Exciting investigative research, widening the dimensions of conventional nuclear medicine, is being conducted in Pretoria where the development and evaluation of new radiopharmaceuticals in particular is attracting international attention. Additional to this, the development of new diagnostic techniques involving sophisticated data processing, is helping to place South Africa firmly in the front line of nuclear medical progress.

Examination of the Current Approaches to State-Level Nuclear Security Evaluation

International Nuclear Information System (INIS)

Kim, Chan; Yim, Mansung; Kim, So Young

2014-01-01

An effective global nuclear materials security system will cover all materials, employ international standards and best practices, and reduce risks by reducing weapons-usable nuclear material stocks and the number of locations where they are found. Such a system must also encourage states to accept peer reviews by outside experts in order to demonstrate that effective security is in place. It is thus critically important to create an integrative framework of state-level evaluation of nuclear security as a basis for measuring the level and progress of international effort to secure and control all nuclear materials. There have been studies to represent state-level nuclear security with a quantitative metric. A prime example is the Nuclear Materials Security Index (NMSI) by the Nuclear Threat Initiative (NTI). Another comprehensive study is the State Level Risk Metric by Texas A and M University (TAMU). This paper examines the current methods with respect to their strengths and weaknesses and identifies the directions for future research to improve upon the existing approaches

Transmutation of high level nuclear waste in an accelerator driven system: towards a demonstration device of industrial interest (EUROTRANS)

International Nuclear Information System (INIS)

Knebel, Joachim U.; Ait Abderrahim, Hamid; Caron-Carles, Marylise

2010-01-01

The Integrated Project EUROTRANS (EURopean Research Programme for the TRANSmutation of High Level Nuclear Waste in an Accelerator Driven System) within the ongoing EURATOM 6th Framework Programme (FP6) is devoted to the study of transmutation of high-level waste from nuclear power plants. The work is focused on transmutation in an Accelerator Driven System (ADS). The objective of EUROTRANS is the assessment of the design and the feasibility of an industrial ADS prototype dedicated to transmutation. The necessary R and D results in the areas of accelerator components, fuel development, structural materials, thermal-hydraulics, heavy liquid metal technology and nuclear data will be made available, together with the experimental demonstration of the ADS component coupling. The outcome of this work will allow to provide a reasonably reliable assessment of technological feasibility and a cost estimate for ADS based transmutation, and to possibly decide on the detailed design of an experimental ADS and its construction in the future. EUROTRANS is integrating activities of 51 participants from 16 countries, within the industry (10 participants), the national research centres (20) and 17 universities. 16 universities are collectively represented by ENEN (European Nuclear Education Network). EUROTRANS is the continuation of the three FP5 Clusters FUETRA, BASTRA and TESTRA together with the PDS-XADS Project. It is a five-year project which started in April 2005

Disposal of high level nuclear wastes: Thermodynamic equilibrium and environment ethics

Institute of Scientific and Technical Information of China (English)

RANA Mukhtar Ahmed

2009-01-01

Contamination of soil, water or air, due to a failure of containment or disposal of high level nuclear wastes, can potentially cause serious hazards to the environment or human health. Essential elements of the environment and radioactivity dangers to it are illustrated. Issues of high level nuclear waste disposal are discussed with a focus on thermodynamic equilibrium and environment ethics. Major aspects of the issues are analyzed and described briefly to build a perception of risks involved and ethical implications. Nuclear waste containment repository should be as close as possible to thermodynamic equilibrium. A clear demonstration about safety aspects of nuclear waste management is required in gaining public and political confidence in any possible scheme of permanent disposal. Disposal of high level nuclear waste offers a spectrum of environment connected challenges and a long term future of nuclear power depends on the environment friendly solution of the problem of nuclear wastes.

Pulse superimposition calculational methodology for estimating the subcriticality level of nuclear fuel assemblies

International Nuclear Information System (INIS)

Talamo, Alberto; Gohar, Y.; Rabiti, C.; Aliberti, G.; Kondev, F.; Smith, D.; Zhong, Z.; Kiyavitskaya, H.; Bournos, V.; Fokov, Y.; Routkovskaya, C.; Serafimovich, I.

2009-01-01

One of the most reliable experimental methods for measuring the subcriticality level of a nuclear fuel assembly is the Sjoestrand method applied to the reaction rate generated from a pulsed neutron source. This study developed a new analytical methodology simulating the Sjoestrand method, which allows comparing the experimental and analytical reaction rates and the obtained subcriticality levels. In this methodology, the reaction rate is calculated due to a single neutron pulse using MCNP/MCNPX computer code or any other neutron transport code that explicitly simulates the delayed fission neutrons. The calculation simulates a single neutron pulse over a long time period until the delayed neutron contribution to the reaction rate is vanished. The obtained reaction rate is then superimposed to itself, with respect to the time, to simulate the repeated pulse operation until the asymptotic level of the reaction rate, set by the delayed neutrons, is achieved. The superimposition of the pulse to itself was calculated by a simple C computer program. A parallel version of the C program is used due to the large amount of data being processed, e.g. by the Message Passing Interface (MPI). The analytical results of this new calculation methodology have shown an excellent agreement with the experimental data available from the YALINA-Booster facility of Belarus. This methodology can be used to calculate Bell and Glasstone spatial correction factor.

Pulse superimposition calculational methodology for estimating the subcriticality level of nuclear fuel assemblies

Energy Technology Data Exchange (ETDEWEB)

Talamo, Alberto [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)], E-mail: atalamo@anl.gov; Gohar, Y. [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Rabiti, C. [Idaho National Laboratory, P.O. Box 2528, Idaho Falls, ID 83403 (United States); Aliberti, G.; Kondev, F.; Smith, D.; Zhong, Z. [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Kiyavitskaya, H.; Bournos, V.; Fokov, Y.; Routkovskaya, C.; Serafimovich, I. [Joint Institute for Power and Nuclear Research-Sosny, National Academy of Sciences (Belarus)

2009-07-21

One of the most reliable experimental methods for measuring the subcriticality level of a nuclear fuel assembly is the Sjoestrand method applied to the reaction rate generated from a pulsed neutron source. This study developed a new analytical methodology simulating the Sjoestrand method, which allows comparing the experimental and analytical reaction rates and the obtained subcriticality levels. In this methodology, the reaction rate is calculated due to a single neutron pulse using MCNP/MCNPX computer code or any other neutron transport code that explicitly simulates the delayed fission neutrons. The calculation simulates a single neutron pulse over a long time period until the delayed neutron contribution to the reaction rate is vanished. The obtained reaction rate is then superimposed to itself, with respect to the time, to simulate the repeated pulse operation until the asymptotic level of the reaction rate, set by the delayed neutrons, is achieved. The superimposition of the pulse to itself was calculated by a simple C computer program. A parallel version of the C program is used due to the large amount of data being processed, e.g. by the Message Passing Interface (MPI). The analytical results of this new calculation methodology have shown an excellent agreement with the experimental data available from the YALINA-Booster facility of Belarus. This methodology can be used to calculate Bell and Glasstone spatial correction factor.

Archival and Dissemination of the U.S. and Canadian Experimental Nuclear Reaction Data (EXFOR Project)

Science.gov (United States)

Pritychenko, Boris; Hlavac, Stanislav; Schwerer, Otto; Zerkin, Viktor

2017-09-01

The Exchange Format (EXFOR) or experimental nuclear reaction database and the associated Web interface provide access to the wealth of low- and intermediate-energy nuclear reaction physics data. This resource includes numerical data sets and bibliographical information for more than 22,000 experiments since the beginning of nuclear science. Analysis of the experimental data sets, recovery and archiving will be discussed. Examples of the recent developments of the data renormalization, uploads and inverse reaction calculations for nuclear science and technology applications will be presented. The EXFOR database, updated monthly, provides an essential support for nuclear data evaluation, application development and research activities. It is publicly available at the National Nuclear Data Center website http://www.nndc.bnl.gov/exfor and the International Atomic Energy Agency mirror site http://www-nds.iaea.org/exfor. This work was sponsored in part by the Office of Nuclear Physics, Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-98CH10886 with Brookha ven Science Associates, LLC.

Summary Report of the Workshop on the Experimental Nuclear Reaction Data Database

International Nuclear Information System (INIS)

Semkova, V.; Pritychenko, B.

2014-12-01

The Workshop on the Experimental Nuclear Reaction Data Database (EXFOR) was held at IAEA Headquarters in Vienna from 6 to 10 October 2014. The workshop was organized to discuss various aspects of the EXFOR compilation process including compilation rules, different techniques for nuclear reaction data measurements, software developments, etc. A summary of the presentations and discussions that took place during the workshop is reported here. (author)

Summary Report of the Workshop on The Experimental Nuclear Reaction Data Database

Energy Technology Data Exchange (ETDEWEB)

Semkova, V. [IAEA Nuclear Data Section, Vienna (Austria); Pritychenko, B. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2014-12-01

The Workshop on the Experimental Nuclear Reaction Data Database (EXFOR) was held at IAEA Headquarters in Vienna from 6 to 10 October 2014. The workshop was organized to discuss various aspects of the EXFOR compilation process including compilation rules, different techniques for nuclear reaction data measurements, software developments, etc. A summary of the presentations and discussions that took place during the workshop is reported here.

Disposal of high level nuclear wastes: thermodynamic equilibrium and environment ethics

International Nuclear Information System (INIS)

Rana, M.A.

2009-01-01

Contamination of soil, water or air, due to a failure of containment or disposal of high level nuclear wastes, can potentially cause serious hazards to the environment or human health. Essential elements of the environment and radioactivity dangers to it are illustrated. Issues of high level nuclear waste disposal are discussed with a focus on thermodynamic equilibrium and environment ethics. Major aspects of the issues are analyzed and described briefly to build a perception of risks involved and ethical implications. Nuclear waste containment repository should be as close as possible to thermodynamic equilibrium. A clear demonstration about safety aspects of nuclear waste management is required in gaining public and political confidence in any possible scheme of permanent disposal. Disposal of high level nuclear waste offers a spectrum of environment connected challenges and a long term future of nuclear power depends on the environment friendly solution of the problem of nuclear wastes. (authors)

Summary of experimental studies on biological effects of radionuclides in Chinese Nuclear Industry

International Nuclear Information System (INIS)

Chen Rusong

1994-11-01

The experimental studies on the biological effects with internal contamination of radionuclides (Such as Uranium, Plutonium, Tritium, Iodine, Radon and its products, etc.) in the Chinese nuclear industry were summarized systematically. In these studies some institutes in the nuclear industry system and other relevant units in China were involved. The review was carried out in both stochastic and deterministic effects, and focused on the dose-effect relationship. The research work showed that great progress for the experimental studies on biological effects with internal irradiation has been made in China. There is a definite characteristic in a certain extent. It makes contribution to develop the production of nuclear industry and the construction of national economy. Several constructive suggestions of prospects for the work in future were proposed and it will make an attention in the field of radiation protection at home and abroad

Developing Curriculum of Nuclear Civil Engineering Degree Programme at Graduate Level

International Nuclear Information System (INIS)

Iqbal, J.

2016-01-01

Full text: The paper suggests the introduction of a new degree, namely nuclear civil engineering at graduate level for better utilization of civil engineers in nuclear power plant (NPP) design and construction. At present, both nuclear engineering and civil engineering degrees are offered at undergraduate and graduate levels in numerous renowned universities of the world. However, when a civil engineer, even after completion of nuclear engineering at postgraduate level, undertakes an assignment related to NPP design, he comes across various problems which are not covered in the present curricula. For instance, NPPs’ siting issues, design of pre-stressed concrete containment against loads of loss of coolant accident (LOCA), various impulsive and impactive loads (e.g., detonations, aircraft crash analysis, etc.) and shielding calculations are some of the core issues during nuclear power plant design. The paper highlights the importance of introduction of nuclear civil engineering degree at the graduate level. Besides, the contents of the proposed course work have also been discussed. Keeping in view the fact that, currently, no such degree is offered in any university of the world, the paper explores useful avenues to human resource development for introducing and expanding nuclear power programmes. (author

High-level nuclear waste disposal

International Nuclear Information System (INIS)

Burkholder, H.C.

1985-01-01

The meeting was timely because many countries had begun their site selection processes and their engineering designs were becoming well-defined. The technology of nuclear waste disposal was maturing, and the institutional issues arising from the implementation of that technology were being confronted. Accordingly, the program was structured to consider both the technical and institutional aspects of the subject. The meeting started with a review of the status of the disposal programs in eight countries and three international nuclear waste management organizations. These invited presentations allowed listeners to understand the similarities and differences among the various national approaches to solving this very international problem. Then seven invited presentations describing nuclear waste disposal from different perspectives were made. These included: legal and judicial, electric utility, state governor, ethical, and technical perspectives. These invited presentations uncovered several issues that may need to be resolved before high-level nuclear wastes can be emplaced in a geologic repository in the United States. Finally, there were sixty-six contributed technical presentations organized in ten sessions around six general topics: site characterization and selection, repository design and in-situ testing, package design and testing, disposal system performance, disposal and storage system cost, and disposal in the overall waste management system context. These contributed presentations provided listeners with the results of recent applied RandD in each of the subject areas

Experimental and calculational works on characteristics of the Dalat Nuclear Research Reactor. Second edition

International Nuclear Information System (INIS)

Pham Ngoc Khoi; Nguyen Kim Dung

2016-03-01

Recognizing the significant value and necessity of publishing the scientific document of experimental and calculational works on the Dalat Nuclear Research Reactor (DNRR) physics and engineering for research, operation, training activities as well as for international scientific exchange, Vietnam Atomic Energy Agency (VAEA) and Vietnam Atomic Energy Institute have completed editing to publish the “Experimental and Calculational Works on Characteristics of THE DALAT NUCLEAR RESEARCH REACTOR” which consists of 26 typical papers representing the most important experimental and calculational results of the DNRR physics and engineering obtained during 30 years of operation and exploitation with the contribution of Vietnamese and former USSR’s experts, especially scientists and engineers working at the Reactor Center of the NRI

Radiation levels in nuclear diagnostic examinations

International Nuclear Information System (INIS)

Vermeulen, A.M.T.I.

1987-01-01

To estimate the risks for a pregnant radiological worker, radiation level measurements are executed for common nuclear diagnostic techniques. These measurements are combined with the time which the radiologic worker is present during the performance of the diagnostic techniques. It is concluded that a radiologic worker is receiving less than 5 mSv during pregnancy. This is the case with in vivo determination in a department of nuclear medicine with common diagnostic techniques. Reduction of radiation doses during pregnancy is possible by reduction of heart function examinations, skeletal examinations and brain scans. 1 figure; 13 tabs

Histogram plots and cutoff energies for nuclear discrete levels

International Nuclear Information System (INIS)

Belgya, T.; Molnar, G.; Fazekas, B.; Oestoer, J.

1997-05-01

Discrete level schemes for 1277 nuclei, from 6 Li through 251 Es, extracted from the Evaluated Nuclear Structure Data File were analyzed. Cutoff energies (U max ), indicating the upper limit of level scheme completeness, were deduced from the inspection of histograms of the cumulative number of levels. Parameters of the constant-temperature level density formula (nuclear temperature T and energy shift U 0 ) were obtained by means of the least square fit of the formula to the known levels below cutoff energy. The results are tabulated for all 1277 nuclei allowing for an easy and reliable application of the constant-temperature level density approach. A complete set of cumulative plots of discrete levels is also provided. (author). 5 figs, 2 tabs

Theory for cross effect dynamic nuclear polarization under magic-angle spinning in solid state nuclear magnetic resonance: the importance of level crossings.

Science.gov (United States)

Thurber, Kent R; Tycko, Robert

2012-08-28

We present theoretical calculations of dynamic nuclear polarization (DNP) due to the cross effect in nuclear magnetic resonance under magic-angle spinning (MAS). Using a three-spin model (two electrons and one nucleus), cross effect DNP with MAS for electron spins with a large g-anisotropy can be seen as a series of spin transitions at avoided crossings of the energy levels, with varying degrees of adiabaticity. If the electron spin-lattice relaxation time T(1e) is large relative to the MAS rotation period, the cross effect can happen as two separate events: (i) partial saturation of one electron spin by the applied microwaves as one electron spin resonance (ESR) frequency crosses the microwave frequency and (ii) flip of all three spins, when the difference of the two ESR frequencies crosses the nuclear frequency, which transfers polarization to the nuclear spin if the two electron spins have different polarizations. In addition, adiabatic level crossings at which the two ESR frequencies become equal serve to maintain non-uniform saturation across the ESR line. We present analytical results based on the Landau-Zener theory of adiabatic transitions, as well as numerical quantum mechanical calculations for the evolution of the time-dependent three-spin system. These calculations provide insight into the dependence of cross effect DNP on various experimental parameters, including MAS frequency, microwave field strength, spin relaxation rates, hyperfine and electron-electron dipole coupling strengths, and the nature of the biradical dopants.

Nuclear engineering experiments at experimental facilities of JNC in graduate course of Tokyo Institute of Technology

International Nuclear Information System (INIS)

Hayashizaki, Noriyosu; Takahashi, Minoru; Aoyama, Takafumi; Onose, Shoji

2005-01-01

Nuclear engineering experiments using outside facilities of the campus have been offered for graduate students in the nuclear engineering course in Tokyo Institute of Technology (Tokyo Tech.). The experiments are managed with the collaboration of Japan Nuclear Cycle Development Institute (JNC), Japan Atomic Energy Research Institute (JAERI) and Research Reactor Institute, Kyoto University (KUR). This report presents the new curriculum of the nuclear engineering experiments at JNC since 2002. The change is due to the shutdown of Deuterium Criticality Assembly Facility (DCA) that was used as an experimental facility until 2001. Reactor physics experiment using the training simulator of the experimental fast reactor JOYO is continued from the previous curriculum with the addition of the criticality approach experiment and control rods calibration. A new experimental subject is an irradiated material experiment at the Material Monitoring Facility (MMF). As a result, both are acceptable as the student experiments on the fast reactor. (author)

Excitation energy and angular momentum dependence of the nuclear level densities

International Nuclear Information System (INIS)

Razavi, R.; Kakavand, T.; Behkami, A. N.

2007-01-01

We have investigated the excitation energy (E) dependence of nuclear level density for Bethe formula and constant temperature model. The level density parameter aa nd the back shifted energy from the Bethe formula are obtained by fitting the complete level schemes. Also the level density parameters from the constant temperature model have been determined for several nuclei. we have shown that the microscopic theory provides more precise information on the nuclear level densities. On the other hand, the spin cut-off parameter and effective moment of inertia are determined by studying of the angular momentum (J) dependence of the nuclear level density, and effective moment of inertia is compared with rigid body value.

Self consitent description of nuclear level densitities

International Nuclear Information System (INIS)

Barranco, M.; Treiner, J.

1980-03-01

We present a self consistent calculation of the nuclear level density based on a generalization to finite temperature of a modified Thomas-Fermi method. A simple expression is derived for the so-called level density parameter a entering the expression of the density of states Xi(E)=Esup(-5/4)e 2 √aE and relating the excitation energy to the temperature E=a T 2 , in terms of nucleons equilibrium densities at T=0 only. One thus avoids the difficulty of adding external constraints to calculate isolated nuclei at finite temperature which are shown to be unstable against particle emission. The role of the nuclear surface is discussed. It is shown that the effective mass of the interaction plays a crucial role in determining the value of a and comparison with experiment confirms the value m*/m > = 1 near the Fermi level obtained through more microscopic analysis

University students' understanding level about words related to nuclear power

International Nuclear Information System (INIS)

Oiso, Shinichi; Watabe, Motoki

2012-01-01

The authors conducted a survey of university students' understanding level about words related to nuclear power before and after Fukushima Daiichi Power Plant accident, and analyzed the difference between before and after the accident. The results show that university students' understanding level improved after the accident, especially in the case of reported words by mass media. Understanding level of some nuclear power security words which were not reported so much by mass media also improved. That may be caused by rising of people's concern about nuclear power generation after the accident, and there is a possibility that the accident motivated people to access such words via internet, journals, etc. (author)

High-level nuclear waste borosilicate glass: A compendium of characteristics

International Nuclear Information System (INIS)

Cunnane, J.C.; Bates, J.K.; Ebert, W.L.; Feng, X.; Mazer, J.J.; Wronkiewicz, D.J.; Sproull, J.; Bourcier, W.L.; McGrail, B.P.

1992-01-01

With the imminent startup, in the United States, of facilities for vitrification of high-level nuclear waste, a document has been prepared that compiles the scientific basis for understanding the alteration of the waste glass products under the range of service conditions to which they may be exposed during storage, transportation, and eventual geologic disposal. A summary of selected parts of the content of this document is provided. Waste glass alterations in a geologic repository may include corrosion of the glass network due to groundwater and/or water vapor contact. Experimental testing results are described and interpreted in terms of the underlying chemical reactions and physical processes involved. The status of mechanistic modeling, which can be used for long-term predictions, is described and the remaining uncertainties associated with long-term simulations are summarized

Computer-based control of nuclear power information systems at international level

International Nuclear Information System (INIS)

Boniface, Ekechukwu; Okonkwo, Obi

2011-01-01

In most highly industrialized countries of the world information plays major role in anti-nuclear campaign. Information and discussions on nuclear power need critical and objective analysis before the structured information presentation to the public to avoid bias anti-nuclear information on one side and neglect of great risk in nuclear power. This research is developing a computer-based information system for the control of nuclear power at international level. The system is to provide easy and fast information highways for the followings: (1) Low Regulatory dose and activity limit as level of high danger for individuals and public. (2) Provision of relevant technical or scientific education among the information carriers in the nuclear power countries. The research is on fact oriented investigation about radioactivity. It also deals with fact oriented education about nuclear accidents and safety. A standard procedure for dissemination of latest findings using technical and scientific experts in nuclear technology is developed. The information highway clearly analyzes the factual information about radiation risk and nuclear energy. Radiation cannot be removed from our environment. The necessity of radiation utilizations defines nuclear energy as two-edge sword. It is therefore, possible to use computer-based information system in projecting and dissemination of expert knowledge about nuclear technology positively and also to use it in directing the public on the safety and control of the nuclear energy. The computer-based information highway for nuclear energy technology is to assist in scientific research and technological development at international level. (author)

Radiation monitoring program at nuclear scientific experimental and educational center - IRT-Sofia

International Nuclear Information System (INIS)

Mladenov, A.; Stankov, D.; Marinov, K.; Nonova, T.; Krezhov, K.

2012-01-01

Ensuring minimal risk of personnel exposure without exceeding the dose limits is the main task of the General Program for Radiation Monitoring of Nuclear Scientific Experimental and Education Centre (NSEEC) with research reactor IRT. Since 2006 the IRT-Sofia is equipped with a new and modern Radiation Monitoring System (RMS). All RMS detectors are connected to the server RAMSYS. They have online (real-time) visualization in two workstations with RAMVISION software. The RMS allows the implementation of technological and environmental monitoring at the nuclear facility site. Environmental monitoring with the RMS external system includes monitoring of dose rate; alpha and beta activity; radon activity; Po-218, Po-214, Po-212 activity; gamma control of vehicles. Technological control of reactor gases includes: Alpha beta particulate monitor; Iodine monitor; Noble gases monitor; Stack flow monitor. The General Program based on the radiation monitoring system allows real-time monitoring and control of radiation parameters in the controlled area and provides for a high level of radiation protection of IRT staff and users of its facilities. This paper presents the technical and functional parameters of the radiation monitoring system and radiation protection activities within the restricted zone in IRT facilities. (authors)

Systematics of nuclear level density parameters

International Nuclear Information System (INIS)

Bucurescu, Dorel; Egidy, Till von

2005-01-01

The level density parameters for the back-shifted Fermi gas (both without and with energy-dependent level density parameter) and the constant temperature models have been determined for 310 nuclei between 18 F and 251 Cf by fitting the complete level schemes at low excitation energies and the s-wave neutron resonance spacings at the neutron binding energies. Simple formulae are proposed for the description of the two parameters of each of these models, which involve only quantities available from the mass tables. These formulae may constitute a reliable tool for extrapolating to nuclei far from stability, where nuclear level densities cannot be measured

Harmonization of nuclear and radiation safety regulations for nuclear power plants with reference levels of Western European Nuclear Regulators Association (WENRA)

International Nuclear Information System (INIS)

Bojchuk, V.S.; Mikolajchuk, O.A.; Gromov, G.V.; Dibach, O.M.; Godovanyuk, G.M.; Nosovs'kij, A.V.

2014-01-01

Self-evaluation of the Ukrainian regulations on nuclear and radiation safety that apply to nuclear power plants for compliance with the reference levels of the Western European Nuclear Regulators Association (WENRA) is presented. Proposals on improvement of the regulations upon self-evaluation are provided

Experimental model of the device for detection of nuclear cycle materials by photoneutron technology

International Nuclear Information System (INIS)

Bakalyarov, A.M.; Karetnikov, M.D.; Kozlov, K.N.; Lebedev, V.I.; Meleshko, E.A.; Obinyakov, B.A.; Ostashev, I.E.; Tupikin, N.A.; Yakovlev, G.V.

2007-01-01

The inherent complexity of sea container control makes them potentially dangerous for smuggling nuclear materials. The experts believe that only active technologies based on recording the products of induced radiation from sensitive materials might solve the problem. The paper reports on the experimental model of the device on the basis of the electron LINAC U-28 for detection of nuclear materials by photonuclear technology. The preliminary numerical optimization of output units (converter, filter, collimator) for shaping the bremsstrahlung was carried out. The setup of experimental device and initial results of recording the prompt and delayed fission products are discussed

Experimental study and nuclear model calculations of {sup 3}He-induced nuclear reactions on zinc

Energy Technology Data Exchange (ETDEWEB)

Al-Abyad, M.; Mohamed, Gehan Y. [Nuclear Research Centre, Atomic Energy Authority, Physics Department (Cyclotron Facility), Cairo (Egypt); Ditroi, F.; Takacs, S.; Tarkanyi, F. [Hungarian Academy of Sciences (ATOMKI), Institute for Nuclear Research, Debrecen (Hungary)

2017-05-15

Excitation functions of {sup 3}He-induced nuclear reactions on natural zinc were measured using the standard stacked-foil technique and high-resolution gamma-ray spectrometry. From their threshold energies up to 27 MeV, the cross-sections for {sup nat}Zn ({sup 3}He,xn) {sup 69}Ge, {sup nat}Zn({sup 3}He,xnp) {sup 66,67,68}Ga, and {sup nat}Zn({sup 3}He,x){sup 62,65}Zn reactions were measured. The nuclear model codes TALYS-1.6, EMPIRE-3.2 and ALICE-IPPE were used to describe the formation of these products. The present data were compared with the theoretical results and with the available experimental data. Integral yields for some important radioisotopes were determined. (orig.)

Quark-level analogue of nuclear fusion with doubly heavy baryons.

Science.gov (United States)

Karliner, Marek; Rosner, Jonathan L

2017-11-01

The essence of nuclear fusion is that energy can be released by the rearrangement of nucleons between the initial- and final-state nuclei. The recent discovery of the first doubly charmed baryon , which contains two charm quarks (c) and one up quark (u) and has a mass of about 3,621 megaelectronvolts (MeV) (the mass of the proton is 938 MeV) also revealed a large binding energy of about 130 MeV between the two charm quarks. Here we report that this strong binding enables a quark-rearrangement, exothermic reaction in which two heavy baryons (Λ c ) undergo fusion to produce the doubly charmed baryon and a neutron n (), resulting in an energy release of 12 MeV. This reaction is a quark-level analogue of the deuterium-tritium nuclear fusion reaction (DT → 4 He n). The much larger binding energy (approximately 280 MeV) between two bottom quarks (b) causes the analogous reaction with bottom quarks () to have a much larger energy release of about 138 MeV. We suggest some experimental setups in which the highly exothermic nature of the fusion of two heavy-quark baryons might manifest itself. At present, however, the very short lifetimes of the heavy bottom and charm quarks preclude any practical applications of such reactions.

Research at the Section of Experimental Nuclear Physics of ATOMKI

International Nuclear Information System (INIS)

Krasznahorkay, A.; Fenyes, T.; Dombradi, Zs.; Nyako, B.M.; Timar, J.; Algora, A.; Csatlos, M.; Csige, L.; Gacsi, Z.; Gulyas, J.

2011-01-01

Introduction. Nuclear physics research was started in Debrecen by Alexander Szalay (1909-1987) back in the 30's. He had been a postdoc of the Nobel-laureate biologist Albert Szent-Gyorgyi in Szeged and of Lord Rutherford in Cambridge. ATOMKI was founded in Debrecen later, in 1954. The Institute was meant to pursue scientific research in certain areas of experimental nuclear physics and to develop research instruments In the early years the country was pretty isolated, but the institute's state of isolation was gradually easing up from the mid-sixties. During the period 1962-1975 the research work was performed in collaboration with Joint Institute for Nuclear Research (Dubna), where up-to-date high-energy accelerators were available for the production of desired isotopes. After finishing the construction of a home-made 5 MV Van de Graaff accelerator (1972) and later on the installation of a K=20 light ion cyclotron (1985) the Institute has become the main centre of accelerator-based nuclear physics in Hungary. In the period 1975-1995 our group performed extensive nuclear structure studies in Debrecen by using γ and conversion electron spectroscopy. At the same time fruitful collaborations were initiated with Jyvaskyla (Finland), with University of Kentucky and University of Zagreb. In 1993 the former Nuclear Reaction Group (NRG) merged with our group. Parallel with this structural change, the main topics of our γ-spectroscopic work has also changed, which resulted that the location of our experiments were shifted from the home institute to foreign large-scale facilities. New topics were brought partly by the emerging NRG, partly by group members returning from postdoctoral fellowships. They also brought important non γ-spectroscopic topics, which enriched our research palette. These new topics have by now become joint endeavours involving more and more group members. The Nuclear Physics European Coordination Committee (NuPECC) has recently stated that the aim of

The experimental nuclear reaction data (EXFOR): Extended computer database and Web retrieval system

Science.gov (United States)

Zerkin, V. V.; Pritychenko, B.

2018-04-01

The EXchange FORmat (EXFOR) experimental nuclear reaction database and the associated Web interface provide access to the wealth of low- and intermediate-energy nuclear reaction physics data. This resource is based on numerical data sets and bibliographical information of ∼22,000 experiments since the beginning of nuclear science. The principles of the computer database organization, its extended contents and Web applications development are described. New capabilities for the data sets uploads, renormalization, covariance matrix, and inverse reaction calculations are presented. The EXFOR database, updated monthly, provides an essential support for nuclear data evaluation, application development, and research activities. It is publicly available at the websites of the International Atomic Energy Agency Nuclear Data Section, http://www-nds.iaea.org/exfor, the U.S. National Nuclear Data Center, http://www.nndc.bnl.gov/exfor, and the mirror sites in China, India and Russian Federation.

Experimental Study of a Multi Level Overtopping Wave Power Device

DEFF Research Database (Denmark)

Kofoed, Jens Peter; Hald, Tue; Frigaard, Peter Bak

2002-01-01

Results of experimental investigations of a floating wave energy device called Power Pyramid is presented. The Power Pyramid utilizes reservoirs in multiple levels when capturing wave overtopping and converting it into electrical energy. The effect of capturing the overtopping in multiple levels,......, using 5 levels introduces practical problems, and is most probably not economically feasible. It is concluded that it is reasonable to use 2 levels (maybe 3), which can increase the efficiency by 25-40 % compared to using a single level.......Results of experimental investigations of a floating wave energy device called Power Pyramid is presented. The Power Pyramid utilizes reservoirs in multiple levels when capturing wave overtopping and converting it into electrical energy. The effect of capturing the overtopping in multiple levels......, compared to only one level, has been evaluated experimentally. From the experimental results, and the performed optimizations based on these, it has been found that the efficiency of a wave power device of the overtopping type can be increased by as much as 76 % by using 5 levels instead of 1. However...

Investigation of analytical and experimental behavior of nuclear facility ventilation systems

International Nuclear Information System (INIS)

Smith, P.R.; Ricketts, C.I.; Andrae, R.W.; Bolstad, J.W.; Horak, H.L.; Martin, R.A.; Tang, P.K.; Gregory, W.S.

1979-01-01

The behavior of nuclear facility ventilation systems subjected to both natural and man-caused accidents is being investigated. The purpose of the paper is to present a program overview and highlight recent results of the investigations. The program includes both analytical and experimental investigations. Computer codes for predicting accident-induced gas dynamics and test facilities to obtain supportive experimental data to define structural integrity and confinement effectiveness of ventilation system components are described. A unique test facility and recently obtained structural limits for high efficiency particulate air filters are reported

Answers to your questions on high-level nuclear waste

International Nuclear Information System (INIS)

1987-11-01

This booklet contains answers to frequently asked questions about high-level nuclear wastes. Written for the layperson, the document contains basic information on the hazards of radiation, the Nuclear Waste Management Program, the proposed geologic repository, the proposed monitored retrievable storage facility, risk assessment, and public participation in the program

Computer-readable ''Nuclear Data Sheets''

International Nuclear Information System (INIS)

Ewbank, W.B.

1975-01-01

The evaluated nuclear structure data contained in ''Nuclear Data Sheets'' are available in computer-readable form. Experimentally established properties of nuclear levels are included as well as radiations from nuclear reactions and radioactive decay. Portions of the data can be selected for distribution in several formats on magnetic tape or computer cards. A variety of different listing and drawing formats are also available. 4 figures

Experimental studies of keV energy neutron-induced reactions relevant to astrophysics and nuclear physics

Energy Technology Data Exchange (ETDEWEB)

Shima, T.; Kii, T.; Kikuchi, T.; Okazaki, F.; Kobayashi, T.; Baba, T.; Nagai, Y. [Tokyo Inst. of Tech. (Japan). Faculty of Science; Igashira, M.

1997-03-01

Nuclear reactions induced by keV energy neutrons provide a plenty of informations for studies of both astrophysics and nuclear physics. In this paper we will show our experimental studies of neutron- induced reactions of light nuclei in the keV energy region by means of a pulsed keV neutron beam and high-sensitivity detectors. Also we will discuss astrophysical and nuclear-physical consequences by using the obtained results. (author)

Managing the high level waste nuclear regulatory commission licensing process

International Nuclear Information System (INIS)

Baskin, K.P.

1992-01-01

This paper reports that the process for obtaining Nuclear Regulatory Commission permits for the high level waste storage facility is basically the same process commercial nuclear power plants followed to obtain construction permits and operating licenses for their facilities. Therefore, the experience from licensing commercial reactors can be applied to the high level waste facility. Proper management of the licensing process will be the key to the successful project. The management of the licensing process was categorized into four areas as follows: responsibility, organization, communication and documentation. Drawing on experience from nuclear power plant licensing and basic management principles, the management requirement for successfully accomplishing the project goals are discussed

EXFOR – a global experimental nuclear reaction data repository: Status and new developments

Directory of Open Access Journals (Sweden)

Semkova Valentina

2017-01-01

Full Text Available Members of the International Network of Nuclear Reaction Data Centres (NRDC have collaborated since the 1960s on the worldwide collection, compilation and dissemination of experimental nuclear reaction data. New publications are systematically complied, and all agreed data assembled and incorporated within the EXFOR database. Recent upgrades to achieve greater completeness of the contents are described, along with reviews and adjustments of the compilation rules for specific types of data.

Identifying Understudied Nuclear Reactions by Text-mining the EXFOR Experimental Nuclear Reaction Library

Energy Technology Data Exchange (ETDEWEB)

Hirdt, J.A. [Department of Mathematics and Computer Science, St. Joseph' s College, Patchogue, NY 11772 (United States); Brown, D.A., E-mail: dbrown@bnl.gov [National Nuclear Data Center, Brookhaven National Laboratory, Upton, NY 11973-5000 (United States)

2016-01-15

The EXFOR library contains the largest collection of experimental nuclear reaction data available as well as the data's bibliographic information and experimental details. We text-mined the REACTION and MONITOR fields of the ENTRYs in the EXFOR library in order to identify understudied reactions and quantities. Using the results of the text-mining, we created an undirected graph from the EXFOR datasets with each graph node representing a single reaction and quantity and graph links representing the various types of connections between these reactions and quantities. This graph is an abstract representation of the connections in EXFOR, similar to graphs of social networks, authorship networks, etc. We use various graph theoretical tools to identify important yet understudied reactions and quantities in EXFOR. Although we identified a few cross sections relevant for shielding applications and isotope production, mostly we identified charged particle fluence monitor cross sections. As a side effect of this work, we learn that our abstract graph is typical of other real-world graphs.

Identifying Understudied Nuclear Reactions by Text-mining the EXFOR Experimental Nuclear Reaction Library

International Nuclear Information System (INIS)

Hirdt, J.A.; Brown, D.A.

2016-01-01

The EXFOR library contains the largest collection of experimental nuclear reaction data available as well as the data's bibliographic information and experimental details. We text-mined the REACTION and MONITOR fields of the ENTRYs in the EXFOR library in order to identify understudied reactions and quantities. Using the results of the text-mining, we created an undirected graph from the EXFOR datasets with each graph node representing a single reaction and quantity and graph links representing the various types of connections between these reactions and quantities. This graph is an abstract representation of the connections in EXFOR, similar to graphs of social networks, authorship networks, etc. We use various graph theoretical tools to identify important yet understudied reactions and quantities in EXFOR. Although we identified a few cross sections relevant for shielding applications and isotope production, mostly we identified charged particle fluence monitor cross sections. As a side effect of this work, we learn that our abstract graph is typical of other real-world graphs.

Nuclear Physics Division, Institute of Experimental Physics, Warsaw University annual report 1995

Energy Technology Data Exchange (ETDEWEB)

Osuch, S [ed.

1997-12-31

In the presented Annual Report the activities of Nuclear Physics Division (NPD) of Warsaw University in 1995 are described. The report consists of three sections: (i) Reaction Mechanism and Nuclear Structure (11 articles); (ii) Instrumentation and Experimental Methods (9 articles); (iii) Other Research (1 article). Additionally the list of seminars held at the NPD, personnel list and list of published papers are also given. The first, leading article in the report written by head of NPD prof. Ch. Droste the general description of the Department activity is presented.

Nuclear Physics Division, Institute of Experimental Physics, Warsaw University annual report 1995

Energy Technology Data Exchange (ETDEWEB)

Osuch, S. [ed.

1996-12-31

In the presented Annual Report the activities of Nuclear Physics Division (NPD) of Warsaw University in 1995 are described. The report consists of three sections: (i) Reaction Mechanism and Nuclear Structure (11 articles); (ii) Instrumentation and Experimental Methods (9 articles); (iii) Other Research (1 article). Additionally the list of seminars held at the NPD, personnel list and list of published papers are also given. The first, leading article in the report written by head of NPD prof. Ch. Droste the general description of the Department activity is presented.

Average Nuclear Level Densities and Radiative Strength Functions in 56,57FE from Primary (Gamma)-Ray Spectra

International Nuclear Information System (INIS)

Tavukcu, E.; Becker, J.A.; Bernstein, L.A.; Garrett, P.E.; Guttormsen, M.; Mitchell, G.E.; Rekstad, J.; Schiller, A.; Siem, S.; Voinov, A.; Younes, W.

2002-01-01

An experimental primary γ-ray spectrum vs. excitation-energy bin (P(E x , E γ ) matrix) in a light-ion reaction is obtained for 56,57 Fe isotopes using a subtraction method. By factorizing the P(E x , E γ ) matrix according to the Axel-Brink hypothesis the nuclear level density and the radiative strength function (RSF) in 56,57 Fe are extracted simultaneously. A step structure is observed in the level density for both isotopes, and is interpreted as the breaking of Cooper pairs. The RSFs for 56,57 Fe reveal an anomalous enhancement at low γ-ray energies

Determination of the lowest critical power levels of the Dalat Nuclear Research Reactor

Energy Technology Data Exchange (ETDEWEB)

Huy, Ngo Quang [Centre for Nuclear Technique Application, Ho Chi Minh City (Viet Nam); Thong, Ha Van; Long, Vu Hai; Binh, Do Quang; Nghiem, Huynh Ton; Tuan, Nguyen Minh; Vien, Luong Ba; Vinh, Le Vinh [Nuclear Research Inst., Da Lat (Viet Nam)

1994-10-01

This paper presents the experimental methods for determining critical states of the Dalat Nuclear Research Reactor containing an extraneous neutron source induced by gamma ray reactions on beryllium in the reactor. The lowest critical power levels are measured at various moments after the reactor is shut down following 100 hours of its continuous operation. Th power levels vary from (0.5-1.2) x 10{sup -4} of P{sub n}, i.e. (25-60)W to (1.1-1.6) x 10{sup -5} of P{sub n}, i.e. (5.5-8)W at corresponding times of 4 days to 13 days after the reactor is shut down. However the critical power must be chosen greater than 500 W to sustain the steady criticality of the reactor for a long time. (author). 3 refs. 4 figs. 1 tab.

Effect of vibrational states on nuclear level density

International Nuclear Information System (INIS)

Plujko, V. A.; Gorbachenko, O. M.

2007-01-01

Simple methods to calculate a vibrational enhancement factor of a nuclear level density with allowance for damping of collective state are considered. The results of the phenomenological approach and the microscopic quasiparticle-phonon model are compared. The practical method of calculation of a vibrational enhancement factor and level density parameters is recommended

Analysis of experimental data on relativistic nuclear collisions in the Lobachevsky space

International Nuclear Information System (INIS)

Baldin, A.A.; Baldina, Eh.G.; Kladnitskaya, E.N.; Rogachevskij, O.V.

2004-01-01

Relativistic nuclear collisions are considered in terms of relative 4-velocity and rapidity space (the Lobachevsky space). The connection between geometric relations in the Lobachevsky space and measurable (experimentally determined) kinematic characteristics (transverse momentum, longitudinal rapidity, square relative 4-velocity b ik , etc.) is discussed. The experimental data obtained using the propane bubble chamber are analyzed on the basis of triangulation in the Lobachevsky space. General properties of relativistic invariants distributions characterizing the geometric position of particles in the Lobachevsky space are discussed. The transition energy region is considered on the basis of relativistic approach to experimental data on multiparticle processes. Possible applications of the obtained results for planning of experimental research and analysis of data on multiple particle production are discussed

Methods and benefits of experimental seismic evaluation of nuclear power plants. Final report

International Nuclear Information System (INIS)

1979-07-01

This study reviews experimental techniques, instrumentation requirements, safety considerations, and benefits of performing vibration tests on nuclear power plant containments and internal components. The emphasis is on testing to improve seismic structural models. Techniques for identification of resonant frequencies, damping, and mode shapes, are discussed. The benefits of testing with regard to increased damping and more accurate computer models are oulined. A test plan, schedule and budget are presented for a typical PWR nuclear power plant

Methods and benefits of experimental seismic evaluation of nuclear power plants. Final report

Energy Technology Data Exchange (ETDEWEB)

1979-07-01

This study reviews experimental techniques, instrumentation requirements, safety considerations, and benefits of performing vibration tests on nuclear power plant containments and internal components. The emphasis is on testing to improve seismic structural models. Techniques for identification of resonant frequencies, damping, and mode shapes, are discussed. The benefits of testing with regard to increased damping and more accurate computer models are oulined. A test plan, schedule and budget are presented for a typical PWR nuclear power plant.

State of the art of computer codes and experimental investigations on safety of nuclear power plants with reactors of WWER type

International Nuclear Information System (INIS)

Asmolov, V.G.; Volkov, G.A.; Elikin, I.V.; Mysenkov, A.I.

1987-01-01

As is well-known investigations on mathematical models of accidental situations from the point of view of nuclear safety as well as their experimental investigation are of great importance in the design of reactor units for nuclear power plants. This paper gives a review of the state of the art of thermodynamic models and computer codes used for safety analysis of WWER reactors in the USSR, the experimental basis and experimental investigations of the appropriate thermal processes. The actual and future trends of theoretical and experimental investigation on safety problems of WWER type nuclear power plants are briefly described. (author)

Water level control for a nuclear steam generator

International Nuclear Information System (INIS)

Wen Tan

2011-01-01

Research highlights: → A water level control system for a nuclear steam generator (SG) is proposed. → The parameters of the control system are directly related to those of the plant model thus scheduling is easy to implement in practice. → The proposed gain-scheduled controller can achieve good performance at both low and high power levels. - Abstract: A water level control system for a nuclear steam generator (SG) is proposed. The control system consists of a feedback controller and a feedforward controller. The feedback controller is of first order, the feedforward controller is of second order, and parameters of the two controllers are directly related to the parameters of plant model thus scheduling is easy to implement in practice. Robustness and performance of the feedback and the feedforward controllers are analyzed in details and tuning of the two parameters of the controllers are discussed. Comparisons among a single robust controller, a multi-model controller and a gain-scheduled controller are studied. It is shown that the proposed gain-scheduled controller can achieve good performance at both low and high power levels.

Combinatorial nuclear level density by a Monte Carlo method

International Nuclear Information System (INIS)

Cerf, N.

1994-01-01

We present a new combinatorial method for the calculation of the nuclear level density. It is based on a Monte Carlo technique, in order to avoid a direct counting procedure which is generally impracticable for high-A nuclei. The Monte Carlo simulation, making use of the Metropolis sampling scheme, allows a computationally fast estimate of the level density for many fermion systems in large shell model spaces. We emphasize the advantages of this Monte Carlo approach, particularly concerning the prediction of the spin and parity distributions of the excited states,and compare our results with those derived from a traditional combinatorial or a statistical method. Such a Monte Carlo technique seems very promising to determine accurate level densities in a large energy range for nuclear reaction calculations

[Experimental nuclear physics

International Nuclear Information System (INIS)

1990-04-01

This report contains brief discussion on the following tapes: giant resonances; nucleus-nucleus reactions; nuclear astrophysics; polarization; fundamental symmetries and interactions; accelerator mass spectrometry; instrumentation; accelerators and in sources; and computer systems

An approach for determining the acceptable levels of nuclear risk

International Nuclear Information System (INIS)

1978-03-01

The objective of this study was to develop a methodology for determining the acceptable levels of risk with respect to nuclear energy. It was concluded that the Atomic Energy Control Board should identify the interest groups that affect its choice of an acceptable level of risk, determine their expectations, and balance the expectations of the various groups such that the resulting acceptable level of risk is still acceptable to the Board. This would be done by interviewing experts on the subject of nuclear safety, developing and pretesting a public questionnaire, and surveying the public on acceptable cost-risk combinations

Technology readiness levels for advanced nuclear fuels and materials development

Energy Technology Data Exchange (ETDEWEB)

Carmack, W.J., E-mail: jon.carmack@inl.gov [Idaho National Laboratory, Idaho Falls, ID (United States); Braase, L.A.; Wigeland, R.A. [Idaho National Laboratory, Idaho Falls, ID (United States); Todosow, M. [Brookhaven National Laboratory, Upton, NY (United States)

2017-03-15

Highlights: • Definition of nuclear fuels system technology readiness level. • Identification of evaluation criteria for nuclear fuel system TRLs. • Application of TRLs to fuel systems. - Abstract: The Technology Readiness process quantitatively assesses the maturity of a given technology. The National Aeronautics and Space Administration (NASA) pioneered the process in the 1980s to inform the development and deployment of new systems for space applications. The process was subsequently adopted by the Department of Defense (DoD) to develop and deploy new technology and systems for defense applications. It was also adopted by the Department of Energy (DOE) to evaluate the maturity of new technologies in major construction projects. Advanced nuclear fuels and materials development is needed to improve the performance and safety of current and advanced reactors, and ultimately close the nuclear fuel cycle. Because deployment of new nuclear fuel forms requires a lengthy and expensive research, development, and demonstration program, applying the assessment process to advanced fuel development is useful as a management, communication, and tracking tool. This article provides definition of technology readiness levels (TRLs) for nuclear fuel technology as well as selected examples regarding the methods by which TRLs are currently used to assess the maturity of nuclear fuels and materials under development in the DOE Fuel Cycle Research and Development (FCRD) Program within the Advanced Fuels Campaign (AFC).

Calculation of nuclear excitation in an electron transition

Energy Technology Data Exchange (ETDEWEB)

Pisk, K. (Institut Rudjer Boskovic, Zagreb (Yugoslavia)); Kaliman, Z. (Rijeka Univ. (Yugoslavia). Faculty of Pedagogics); Logan, B.A. (Ottawa Univ., ON (Canada). Ottawa-Carleton Centre for Physics)

1989-11-06

We have made a theoretical investigation of nuclear excitation during an electron transition (NEET). Our approach allows us to express the NEET probabilities in terms of the excited nuclear level width, the energy difference between the nuclear and electron transition, the Coulomb interaction between the initial electron states, and the electron level width. A comparison is made with the available experimental results. (orig.).

Nuclear spectroscopic studies

International Nuclear Information System (INIS)

Bingham, C.R.; Guidry, M.W.; Riedinger, L.L.; Sorensen, S.P.

1994-01-01

The Nuclear Physics group at UTK is involved in heavy-ion physics including both nuclear structure and reaction mechanisms. During the last year experimental work has been in 3 broad areas: structure of nuclei at high angular momentum, structure of nuclei far from stability, and ultra-relativistic heavy-ion physics. Results in these areas are described in this document under: properties of high-spin states, study of low-energy levels of nuclei far from stability, and high-energy heavy-ion physics (PHENIX, etc.). Another important component of the work is theoretical interpretation of experimental results (Joint Institute for Heavy Ion Research)

Nuclear magnetic resonance. Present results and its application to renal pathology. Experimental study of hydronephrosis

International Nuclear Information System (INIS)

Bertrand, P.

1987-01-01

Results of proton nuclear magnetic resonance imaging and relaxation time measurement of experimental hydronephrosis in mice are presented. The study is preceded by a description of the physical principles underlying the phenomenon of nuclear magnetic resonance and of its biomedical applications and with a review of the clinical use of NMR imaging in renal pathology [fr

Using Direct Sub-Level Entity Access to Improve Nuclear Stockpile Simulation Modeling

Energy Technology Data Exchange (ETDEWEB)

Parker, Robert Y. [Brigham Young Univ., Provo, UT (United States)

1999-08-01

Direct sub-level entity access is a seldom-used technique in discrete-event simulation modeling that addresses the accessibility of sub-level entity information. The technique has significant advantages over more common, alternative modeling methods--especially where hierarchical entity structures are modeled. As such, direct sub-level entity access is often preferable in modeling nuclear stockpile, life-extension issues, an area to which it has not been previously applied. Current nuclear stockpile, life-extension models were demonstrated to benefit greatly from the advantages of direct sub-level entity access. In specific cases, the application of the technique resulted in models that were up to 10 times faster than functionally equivalent models where alternative techniques were applied. Furthermore, specific implementations of direct sub-level entity access were observed to be more flexible, efficient, functional, and scalable than corresponding implementations using common modeling techniques. Common modeling techniques (''unbatch/batch'' and ''attribute-copying'') proved inefficient and cumbersome in handling many nuclear stockpile modeling complexities, including multiple weapon sites, true defect analysis, and large numbers of weapon and subsystem types. While significant effort was required to enable direct sub-level entity access in the nuclear stockpile simulation models, the enhancements were worth the effort--resulting in more efficient, more capable, and more informative models that effectively addressed the complexities of the nuclear stockpile.

Experimental nuclear physics. Progress report, August 1985-August 1986

International Nuclear Information System (INIS)

1986-01-01

The research activities of the experimental nuclear structure group at Vanderbilt University are reported here. Research continues in the areas of (1) in-beam γ-ray spectroscopy; (2) studies of nuclei far from stability at UNISOR and at the recoil mass spectrometer at the University of Rochester; (3) nucleon transfer reaction and fusion-fission studies; and (4) theoretical studies. In general, abstracts of papers published or submitted for publication in this period make up this report along with brief reports of work in process and complete copies of a few conference papers

The international thermonuclear experimental reactor and the future of nuclear fusion energy

International Nuclear Information System (INIS)

Pan Chuanhong

2010-01-01

Energy shortage and environmental problems are now the two largest challenges for human beings. Magnetic confinement nuclear fusion, which has achieved great progress since the 1990's, is anticipated to be a way to realize an ideal source of energy in the future because of its abundance, environmental compatibility, and zero carbon release. Exemplified by the construction of the International Thermonuclear Experimental Reactor (ITER), the development of nuclear fusion energy is now in its engineering phase, and should be realized by the middle of this century if all objectives of the ITER project are met. (author)

Nuclear physics accelerator facilities

International Nuclear Information System (INIS)

1985-01-01

The Department of Energy's Nuclear Physics program is a comprehensive program of interdependent experimental and theoretical investigation of atomic nuclei. Long range goals are an understanding of the interactions, properties, and structures of atomic nuclei and nuclear matter at the most elementary level possible and an understanding of the fundamental forces of nature by using nuclei as a proving ground. Basic ingredients of the program are talented and imaginative scientists and a diversity of facilities to provide the variety of probes, instruments, and computational equipment needed for modern nuclear research. Approximately 80% of the total Federal support of basic nuclear research is provided through the Nuclear Physics program; almost all of the remaining 20% is provided by the National Science Foundation. Thus, the Department of Energy (DOE) has a unique responsibility for this important area of basic science and its role in high technology. Experimental and theoretical investigations are leading us to conclude that a new level of understanding of atomic nuclei is achievable. This optimism arises from evidence that: (1) the mesons, protons, and neutrons which are inside nuclei are themselves composed of quarks and gluons and (2) quantum chromodynamics can be developed into a theory which both describes correctly the interaction among quarks and gluons and is also an exact theory of the strong nuclear force. These concepts are important drivers of the Nuclear Physics program

Preface: Eighth European Summer School on Experimental Nuclear Astrophysics

International Nuclear Information System (INIS)

Claudio, Spitaleri; Livio, Lamia; Gianluca, Pizzone Rosario

2016-01-01

In this book a collection of the lecture notes given during the Eighth European Summer School on Experimental Nuclear Astrophysics is given. The school, whose first edition was first held in 2003, took place from 13 to 20 of September 2015 in Santa Tecla, a small village about 15 km north of Catania, characterized by its position on the volcanic shores of the Ionian Sea, surrounded by the spectacular “Timpa” area, a green protected park specific for its mediterranean vegetation. 80 young students and researchers from more than 20 countries attended the lectures and were also encouraged to present their work and results. The school, has tried once more to present to the young students the global picture of nuclear astrophysics research in the last years. Thus the scientific program of the school covered a wide range of topics dealing with various aspects of nuclear astrophysics, such as stellar evolution and nucleosynthesis, neutrino physics, the Big Bang, direct and indirect methods and radioactive ion beams. Nuclear astrophysics plays a key role in understanding energy production in stars, stellar evolution and the concurrent synthesis of the chemical elements and their isotopes. It is also a fundamental tool to explain the ashes of the early universe, to determine the age of the universe through the study of pristine stellar objects and to predict the evolution of the Sun or Stars. The “bone structure” for the above aspects is based on nuclear reactions, whose rates need to be determined in laboratories. Although impressive progress has been made over the past decades, which was rewarded by Nobel prizes, several open questions are still unsolved, which challenge the basis of the present understanding. A list of the lecture topics is given below: —Big Bang Nucleosynthesis —Stellar evolution and Nucleosynthesis —radioactive ion beams —detector and facilities for nuclear astrophysics —indirect methods in nuclear astrophysics —plasma physics An

Nuclear Structure Data for the Present Age

International Nuclear Information System (INIS)

Baglin, Coral M.

2005-01-01

The US Nuclear Data Program maintains and provides easy and free access to several comprehensive databases that assist scientists to sift through and assess the vast quantity of published nuclear structure and decay data. These databases are an invaluable asset for nuclear-science experimentalists and theorists alike, and the recommended values provided for nuclear properties such as decay modes, level energies and lifetimes, and radiation properties can also be of great importance to specialists in other fields such as medicine, geophysics, and reactor design. The Evaluated Nuclear Structure Data File (ENSDF) contains experimental nuclear structure data for all known nuclides, evaluated by the US nuclear data program evaluators in collaboration with a number of international data groups; the Nuclear Science Reference (NSR) database provides complementary bibliographic information; the Experimental Unevaluated Nuclear Data Listing (XUNDL) exists to enable rapid access to experimental nuclear-structure data compiled from the most recent publications (primarily in high-spin physics). This paper presents an overview of the nuclear structure and decay data available through these databases, with emphasis on recent and forthcoming additions to and presentations of the available material

High-level nuclear waste disposal: Ethical considerations

International Nuclear Information System (INIS)

Maxey, M.N.

1985-01-01

Popular skepticism about, and moral objections to, recent legislation providing for the management and permanent disposal of high-level radioactive wastes have derived their credibility from two major sources: government procrastination in enacting waste disposal program, reinforcing public perceptions of their unprecedented danger and the inflated rhetoric and pretensions to professional omnicompetence of influential scientists with nuclear expertise. Ethical considerations not only can but must provide a mediating framework for the resolution of such a polarized political controversy. Implicit in moral objections to proposals for permanent nuclear waste disposal are concerns about three ethical principles: fairness to individuals, equitable protection among diverse social groups, and informed consent through due process and participation

Application of smart transmitter technology in nuclear engineering measurements with level detection algorithm

International Nuclear Information System (INIS)

Kang, Hyun Gook; Seong, Poong Hyun

1994-01-01

In this study a programmable smart transmitter is designed and applied to the nuclear engineering measurements. In order to apply the smart transmitter technology to nuclear engineering measurements, the water level detection function is developed and applied in this work. In the real time system, the application of level detection algorithm can make the operator of the nuclear power plant sense the water level more rapidly. Furthermore this work can simplify the data communication between the level-sensing thermocouples and the main signal processor because the level signal is determined at field. The water level detection function reduces the detection time to about 8.3 seconds by processing the signal which has the time constant 250 seconds and the heavy noise signal

Large model-space calculation of the nuclear level density parameter

International Nuclear Information System (INIS)

Agrawal, B.K.; Samaddar, S.K.; De, J.N.; Shlomo, S.

1998-01-01

Recently, several attempts have been made to obtain nuclear level density (ρ) and level density parameter (α) within the microscopic approaches based on path integral representation of the partition function. The results for the inverse level density parameter K es and the level density as a function of excitation energy are presented

Combined conditioning in the high-temperature experimental nuclear reactor (AVR) at Juelich

International Nuclear Information System (INIS)

Nieder, R.; Vey, K.; Ivens, G.

1984-01-01

The high temperature experimental nuclear reactor (AVR) is the first nuclear power plant in which combined cycle operation has been introduced. The water-steam cycle has been operated for about 15 years according to the alkali method of working with ammonia and hydrazine. The VGB-guidelines have been adhered to througout. Since January 1983 cobined cycle operation has been employed, and in this process a pH-value of about 8.5 and an oxygen concentration of about 200 μg/kg in the feedwater have been used. A distinct reduction of tritium concentration in the water-steam cycle was the outstanding new result. (orig.) [de

Both experimental hypothyroidism and hyperthyroidism increase cardiac irisin levels in rats.

Science.gov (United States)

Atici, E; Menevse, E; Baltaci, A K; Mogulkoc, R

2018-01-01

Irisin is a newly discovered myokine and adipokine that increases total body energy expenditure. The aim of this study was to determine the effect of experimental hypothyroidism and hyperthyroidism on the levels of irisin in heart tissue in rats. The study was performed on the 40 male Sprague-Dawley rats. Experimental groups were designed as; Control, Hypothyroidism, Hypothyroidism+L-Thyroxine, Hyperthyroidism and Hyperthyroidism + PTU. Following 3 weeks experimental period, irisin levels were determined in heart tissues. Hypothyroidism group values of irisin were higher than in the control group, but lower than in the hyperthyroidism group. The hyperthyroidism group had the highest levels of cardiac irisin. The results of the study showed that the experimental hypothyroidism and hyperthyroidism increased the heart irisin levels, but the increase in the hyperthyroidism group was much higher than in the hypothyroidism group. However, treatment of hypothyroidism and hyperthyroidism corrected cardiac irisin levels (Fig. 1, Ref. 28).

On expectation values for nuclear energy levels

International Nuclear Information System (INIS)

De Wet, J.A.

1978-01-01

The nuclear model is built up by constructing measured states, including the ground state, from the vacuum state. All states are, however, not accessible from the ground state so that selection rules may be found which at the same time impose even more stringent conditions on the labelling of energy levels. These are the subject of this paper

Low-level nuclear waste tested for fertilizer value

International Nuclear Information System (INIS)

Anon.

1987-01-01

The nuclear power industry keeps coming up with proposals for getting rid of radioactive waste - burying it deep in the ground, sinking it at sea and even sending it into space reports Common Cause magazine under a headline, The Latest in Recycling. At its Sequoyah Fuels facility in Oklahoma, Kerr-McGee manufactures fuel for nuclear power plants, generating a low-level radioactive liquid waste product called raphinate. After processing to remove radioactive substances, Kerr-McGee has gotten approval from the Nuclear Regulatory Commission to use the nitrogen-rich residue as a fertilizer - but not to market it. As a result, Kerr-McGee is reported to be buying up thousands of acres of land on which to spread raphinate. The acreage is used to grow hay, which the company has gotten an okay to sell. The recycling effort hasn't exactly won neighborhood friends for the company, noted Common Cause. According to Kerr-McGee's corporate communications direct, When you say to somebody, Sequoyah Fuels is putting nuclear waste (on farmland), people jump up a wall

Low-level nuclear waste in Washington State

International Nuclear Information System (INIS)

Williams, H.

1986-01-01

A commercial disposal site for low-level nuclear wastes opened at Hanford in 1965. By 1971 a total of six were in operation: Hanford, Nevada, South Carolina, Kentucky, New York State, and Illinois. The history of the operation of these sites is described. Only the first three listed are still open. The effects of the large volumes of waste expected from Three Mile Island are described. This paper examines the case history of Hanford operations with low-level waste disposal for lessons that might apply in other states being considered for disposal sites

Hydraulic properties of buffer and backfill materials for high-level nuclear waste disposal

International Nuclear Information System (INIS)

Komine, Hideo; Ogata, Nobuhide

2001-01-01

The design and development of buffer and backfill materials, which fill up the disposal facility, are important for developing the technology of high-level nuclear wastes disposal. The compacted bentonite and sand-bentonite mixture are attracting greater attention as buffer and backfill materials because they have impermeable and swelling properties. This study investigated the hydraulic-conductivities at the different sand-bentonite mass ratio and dry density, which are the specifications of material, by the experimental works. This study also obtained the experimental data of hydraulic conductivities of the materials for 120 days at the farthest, and the permeability changes before and after swelling. Furthermore, this study proposed the evaluation method for hydraulic conductivity using the parameter 'Swelling volumetric strain of montmorillonite', which was proposed by the author. The evaluation method can obtain the hydraulic conductivity of buffer and backfill materials at various dry densities and bentonite contents. Therefore, the evaluation method can be used for designing the bentonite content and compaction density from the viewpoint of 'impermeability'. (author)

Development of nuclear thermal hydraulic verification tests and evaluation technology - Development of the ultrasonic method for two-phase mixture level measurement in nuclear reactor

Energy Technology Data Exchange (ETDEWEB)

No, Hee Cheon; Kim, Sang Jae; Kim, Hyung Tae; Moon, Young Min [Korea Advanced Institute of Science and Technology, Taejon (Korea)

2000-04-01

An ultrasonic method is developed for the measurement of the two-phase mixture level in the reactor vessel or steam generator. The ultrasonic method is selected among the several non-nuclear two-phase mixture level measurement methods through two steps of selection procedure. A commercial ultrasonic level measurement method is modified for application into the high temperature, pressure, and other conditions. The calculation method of the ultrasonic velocity is modified to consider the medium as the homogeneous mixture of air and steam, and to be applied into the high temperature and pressure conditions. The cross-correlation technique is adopted as a detection method to reduced the effects of the attenuation and the diffused reflection caused by surface fluctuation. The waveguides are developed to reduce the loss of echo and to remove the effects of obstructs. The present experimental study shows that the developed ultrasonic method measures the two-phase mixture level more accurately than the conventional methods do. 21 refs., 60 figs., 13 tabs. (Author)

Nuclear analysis of the experimental VHTR fuel lattice

International Nuclear Information System (INIS)

Doi, Takeshi; Shindo, Ryuiti; Hirano, Mitsumasa; Takano, Makoto

1984-11-01

Nuclear properties of a fuel lattice in the experimental VHTR core were analyzed with DELIGHT-6 and SRAC codes. Analytical results by both codes were compared by using various calculational model. The nuclear parameters were analyzed, such as a multiplication factor of a fuel lattice and it's variation with burnup, a temperature effect on reactivity, an effect of double-heterogeniety in a resonance absorption calculation, a resonance integral of 238 U and a reactivity worth of burnable poison. From these analyses, following results were obtained. Firstly, on calculational models, 1) Effect of double-heterogeniety in the resonance absorption calculation for Mark-III fuel element, causing a decrease of about 5.5 barns in the resonance integral and an increase of about 2.6 %ΔK in the infinite multiplication factor, 2) The heterogeneous calculation with the collision probability method resulted in about 0.6 %ΔK higher the multiplication factor of fuel lattice than that with the point model, 3) The reactivity worth of burnable poison rod by a multi-region model is about 20 % less than that by a 2-region model at an initial state of burnup and it's variation with burnup are fairly different, Secondly, on comparison between the results by DELIGHT-6 and SRAC, 4) The nuclear parameters obtained with both codes agreed well, Lastly, on the improvement in DELIGHT-6, 5) Consideration of the neutron spectrum shielding effect in the resonance effective cross section calculation caused a decrease of about 2.4 %ΔK in the multiplication factor of fuel lattice, 6) The lattice multiplication factor increased about 0.5 %ΔK by introducing lambda-parameters for the non-resonant nuclie. (J.P.N.)

Calculation of nuclear level density parameters of some light deformed medical radionuclides using collective excitation modes of observed nuclear spectra

International Nuclear Information System (INIS)

Okuducu, S.; Sarac, H.; Akti, N. N.; Boeluekdemir, M. H.; Tel, E.

2010-01-01

In this study the nuclear energy level density based on nuclear collective excitation mechanism has been identified in terms of the low-lying collective level bands at near the neutron binding energy. Nuclear level density parameters of some light deformed medical radionuclides used widely in medical applications have been calculated by using different collective excitation modes of observed nuclear spectra. The calculated parameters have been used successfully in estimation of the neutron-capture cross section basic data for the production of new medical radionuclides. The investigated radionuclides have been considered in the region of mass number 40< A< 100. The method used in the present work assumes equidistance spacing of the collective coupled state bands of the interest radionuclides. The present calculated results have been compared with the compiled values from the literatures for s-wave neutron resonance data.

[Experimental nuclear physics

International Nuclear Information System (INIS)

1992-01-01

An earlier study of unusual electromagnetic decays in 86 Zr was extended in order to make comparisons with its isotone 84 Sr and with 84 Zr. The K=14 (t 1/2 = 70 ns) high-spin isomer in 176 W was found to have a 13% branch directly to the K=O ground-state band, one of the strongest violations of K-selection rules known. A new program to search for a predicted region of oblate deformation involving neutron deficient isotopes in the Rn/Fr/Ra region was begun. In the area of nuclear astrophysics, as part of a study of the onset of the rp-Process, a set of measurements searching for possible new resonances for 14 O+α and 17 F+p reactions was completed and a coincidence experiment measuring the 19 F( 3 He,t) 19 Ne(α) 15 O and 19 F( 3 He,t) 19 Ne(p) 18 F reactions in order to determine the rates of the 18 F(p,α) 15 O and 18 F(p,γ) 19 Ne reactions was begun. Experimental measurements of βnα coincidences from the 15 N(d,p) 16 N(β - ν) 16 O(α) 12 C reaction have also been completed and are currently being analyzed to determine the rate of the 12 C(α,γ) reaction. In the APEX collaboration, we have completed the assembly and testing of two position-sensitive Na barrels which surround the axial silicon detector arrays and serve as the e + triggers by detecting their back-to-back annihilation quanta were completed. The HI at sign AGS and RHIC collaborations, construction and implementation activities associated with the space-time-tracker detector and in the design of the central detector for the PHENIX experiment were carried out. Operation of the ESTU tandem accelerator has been reliable, delivering beam on target at terminal voltages as high as 19.3 MV and running for as long as 143 days between tank openings. Fabrication and bench testing of a new negative ion source system have been completed

Multiple external hazards compound level 3 PSA methods research of nuclear power plant

Science.gov (United States)

Wang, Handing; Liang, Xiaoyu; Zhang, Xiaoming; Yang, Jianfeng; Liu, Weidong; Lei, Dina

2017-01-01

2011 Fukushima nuclear power plant severe accident was caused by both earthquake and tsunami, which results in large amount of radioactive nuclides release. That accident has caused the radioactive contamination on the surrounding environment. Although this accident probability is extremely small, once such an accident happens that is likely to release a lot of radioactive materials into the environment, and cause radiation contamination. Therefore, studying accidents consequences is important and essential to improve nuclear power plant design and management. Level 3 PSA methods of nuclear power plant can be used to analyze radiological consequences, and quantify risk to the public health effects around nuclear power plants. Based on multiple external hazards compound level 3 PSA methods studies of nuclear power plant, and the description of the multiple external hazards compound level 3 PSA technology roadmap and important technical elements, as well as taking a coastal nuclear power plant as the reference site, we analyzed the impact of off-site consequences of nuclear power plant severe accidents caused by multiple external hazards. At last we discussed the impact of off-site consequences probabilistic risk studies and its applications under multiple external hazards compound conditions, and explained feasibility and reasonableness of emergency plans implementation.

76 FR 35137 - Vulnerability and Threat Information for Facilities Storing Spent Nuclear Fuel and High-Level...

Science.gov (United States)

2011-06-16

... High-Level Radioactive Waste AGENCY: U.S. Nuclear Regulatory Commission. ACTION: Public meeting... Nuclear Fuel, High-Level Radioactive Waste, and Reactor-Related Greater Than Class C Waste,'' and 73... Spent Nuclear Fuel (SNF) and High-Level Radioactive Waste (HLW) storage facilities. The draft regulatory...

Nuclear structure considerations for gamma-ray lasers

International Nuclear Information System (INIS)

Strottman, D.; Arthur, E.D.; Madland, D.G.

1985-01-01

Presented are initial results in our investigation of the nuclear physics issues of gamma-ray lasers. These include the questions of what is known from existing experimental data, where does one optimally search for nuclei displaying simultaneously both closely lying levels and nuclear isomerism, and which theoretical models does one employ for systematic searches for candidate nuclei and for calculation of detailed candidate level properties

Health and Safety Considerations Associated with Sodium-Cooled Experimental Nuclear Fuel Dismantlement

Energy Technology Data Exchange (ETDEWEB)

Carvo, Alan E. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2015-04-01

Between the mid-1970s and the mid-1980s Sandia National Laboratory constructed eleven experimental assemblies to simulate debris beds formed in a sodium-cooled fast breeder reactor. All but one of the assemblies were irradiated. The experimental assemblies were transferred to the Idaho National Laboratory (INL) in 2007 and 2008 for storage, dismantlement, recovery of the uranium for reuse in the nuclear fuel cycle, and disposal of unneeded materials. This paper addresses the effort to dismantle the assemblies down to the primary containment vessel and repackage them for temporary storage until such time as equipment necessary for sodium separation is in place.

Determination of leveled costs of electric generation for gas plants, coal and nuclear

International Nuclear Information System (INIS)

Alonso V, G.; Palacios H, J.C.; Ramirez S, J.R.; Gomez, A.

2005-01-01

The present work analyzes the leveled costs of electric generation for different types of nuclear reactors known as Generation III, these costs are compared with the leveled costs of electric generation of plants with the help of natural gas and coal. In the study several discount rates were used to determine their impact in the initial investment. The obtained results are comparable with similar studies and they show that it has more than enough the base of the leveled cost the nuclear option it is quite competitive in Mexico. Also in this study it is also thinks about the economic viability of a new nuclear power station in Mexico. (Author)

Experimental study of self-leveling behavior in debris bed

International Nuclear Information System (INIS)

Zhang, Bin; Harada, Tetsushi; Hirahara, Daisuke; Matsumoto, Tatsuya; Morita, Koji; Fukuda, Kenji; Yamano, Hidemasa; Suzuki, Tohru; Tobita, Yoshiharu

2008-01-01

After a core disruptive accident in a sodium-cooled fast reactor, core debris may settle on locations such as within the core-support structure or in the lower inlet plenum of the reactor vessel as debris beds, as a consequence of rapid quenching and fragmentation of core materials in subcooled sodium. The particle beds that are initially of varying depth have been observed to undergo a process of self-leveling when sodium boiling occurs within the beds. The boiling is believed to provide the driven force with debris needed to overcome resisting forces. Self-leveling ability has much effect on heat-removal capability of debris beds. In the present study, characteristics of self-leveling behaviors were investigated experimentally with simulant materials. Although the decay heat from fuel debris drives the coolant boiling in reactor accident conditions, the present experiments employed depressurization boiling of water to simulate axially increasing void distribution in a debris bed, which consists of solid particles of alumina or lead with different density. The particle size (from 0.5 mm to 6 mm in diameter) and shape (spherical or non-spherical particles) were also taken as experimental parameters. A rough criteria for self-leveling occurrence is proposed and compared with the experimental results. Characteristics of the self-leveling behaviors observed are analyzed and extrapolate to reactor accident conditions. (author)

Experimental Observation of Nuclear Reactions in Palladium and Uranium

International Nuclear Information System (INIS)

J. Dufour; D. Murat; X. Dufour; J. Foos

2001-01-01

By submitting various metals (Pd, U) containing hydrogen (from 2000 to 700 000 atoms of hydrogen for 1 000 000 atoms of the host metal) to the combined action of electrical currents and magnetic fields, we have observed a sizeable exothermal effect (from 0.1 to 8 W for 500 mg of metal used). This effect is beyond experimental errors, the energy output being typically 130 to 250% of the energy input and not of chemical origin (exothermal effect in the range of 7000 MJ/mol of metal in the case of palladium and of 60 MJ/mol in the case of uranium). New chemical species also appear in the processes metals. It has been shown by a QED calculation that resonances of long lifetime (s), nuclear dimensions (fm), and low energy of formation (eV) could exist. This concept seems to look like the 'shrunken hydrogen atoms' proposed by various authors. It is indeed very different in two ways (a) being a metastable state, it needs energy to be formed (a few eV) and reverts to normal hydrogen after a few seconds, liberating back its energy of formation (it is thus not the source of the energy observed); (b) its formation can be described as the electron spin/proton nuclear spin interaction becoming first order in the lattice environment (whereas it is third order in a normal hydrogen atom). Moreover, we consider that the hydrex cannot yield a neutron because this reaction is strongly endothermic. To explain our results, we put forward the following working hypothesis: In a metal lattice and under proper conditions, the formation of such resonances (metastable state) could be favored. We propose to call them HYDREX, and we assume that they are actually formed in cold fusion (CF) and low-energy nuclear reaction (LENR) experiments. Once formed, a number of HYDREX could gather around a nucleus of the lattice to form a cluster of nuclear size and of very long life time compared to nuclear time (10 -22 s). In this cluster, nuclear rearrangements could take place, yielding mainly 4 He

A systematic study of distribution characters of infiltration parameters in an experimental basin by nuclear methods

International Nuclear Information System (INIS)

Gu Weizu; Lu Jieju; Lu Mingjiang; Chen Tingyang

1988-01-01

A case study of spatial variability of Philip's infiltration parameters was carried out in a small experimental catchment with an area of 0.8 ha by nuclear monitoring methods. Relationships between sorptivity S, parameter A and the average initial soil water content within 0.5 m depth of soil profiles over the catchment have been plotted. A watershed infiltration parameter distribution curve is set up and fitted approximately by f/F=1-(1-S/S M ) n . The parameters of composite infiltration response related to whole catchment are suggested. The author has studied it on an experimental basin by combined method of nuclear technology and micro-geomorphic analysis. The results are satisfactory. (author). 6 refs, 11 figs, 2 tabs

Immobilisation of high level nuclear reactor wastes in SYNROC

Energy Technology Data Exchange (ETDEWEB)

Ringwood, A E; Kesson, S E; Ware, N G; Hibberson, W; Major, A [Australian National Univ., Canberra. Inst. of Advanced Studies

1979-03-15

It is stated that the elements occurring in high-level nuclear reactor wastes can be safely immobilised by incorporating them within the crystal lattices of the constituent minerals of a synthetic rock (SYNROC). The preferred form of SYNROC can accept up to 20% of high level waste calcine to form dilute solid solutions. The constituent minerals, or close structural analogues, have survived in a wide range of geochemical environments for periods of 20 to 2,000 Myr whilst immobilising the same elements present in nuclear wastes. SYNROC is unaffected by leaching for 24 hours in pure water or 10 wt % NaCl solution at high temperatures and pressure whereas borosilicate glasses completely decompose in a few hours in much less severe hydrothermal conditions. The combination of these leaching results with the geological evidence of long-term stability indicates that SYNROC would be vastly superior to glass in its capacity to safely immobilise nuclear wastes, when buried in a suitable geological repository. A dense, compact, mechanically strong form of SYNROC suitable for geological disposal can be produced by a process as economical as that which incorporates radioactive waste in borosilicate glasses.

Modeling a nuclear reactor for experimental purposes

International Nuclear Information System (INIS)

Berta, V.T.

1980-01-01

The Loss-of-Fluid Test (LOFT) Facility is a scale model of a commercial PWR and is as fully functional and operational as the generic commercial counterpart. LOFT was designed and built for experimental purposes as part of the overall NRC reactor safety research program. The purpose of LOFT is to assess the capability of reactor safety systems to perform their intended functions during occurrences of off-normal conditions in a commercial nuclear reactor. Off-normal conditions arising from large and small break loss-of-coolant accidents (LOCA), operational transients, and anticipated transients without scram (ATWS) were to be investigated. This paper describes the LOFT model of the generic PWR and summarizes the experiments that have been conducted in the context of the significant findings involving the complex transient thermal-hydraulics and the consequent effects on the commercial reactor analytical licensing techniques. Through these techniques the validity of the LOFT model as a scaled counterpart of the generic PWR is shown

Level repulsion, nuclear chaos, and conserved quantum numbers

International Nuclear Information System (INIS)

Garrett, J.D.

1993-01-01

A statistical analysis of the distribution of level spacings for states with the same spin and parity is described in which the average spacing is calculated for the total ensemble. Though the resulting distribution of level spacings for states of deformed nuclei with Z = 62 - 75 and A = 155 - 185 is the closest to that of a Poisson distribution yet obtained for nuclear levels, significant deviations are observed for small level spacings. Many, but not all, of the very closely-spaced levels have K-values differing by several units. The analysis of level spacings in 157 Ho indicate that considerable caution should be excerised when drawing conclusions from such an analysis for a single deformed nucleus, since the sizable number of spacings that can be obtained from a few rotational bands are not all independent

Nuclear Level Densities for Modeling Nuclear Reactions: An Efficient Approach Using Statistical Spectroscopy

International Nuclear Information System (INIS)

Calvin W. Johnson

2005-01-01

The general goal of the project is to develop and implement computer codes and input files to compute nuclear densities of state. Such densities are important input into calculations of statistical neutron capture, and are difficult to access experimentally. In particular, we will focus on calculating densities for nuclides in the mass range A ∼ 50-100. We use statistical spectroscopy, a moments method based upon a microscopic framework, the interacting shell model. Second year goals and milestones: Develop two or three competing interactions (based upon surface-delta, Gogny, and NN-scattering) suitable for application to nuclei up to A = 100. Begin calculations for nuclides with A = 50-70

University-level education in nuclear and radiochemistry in Slovenia

International Nuclear Information System (INIS)

Smodis, B.

2006-01-01

The status of education in nuclear and radiochemistry in Slovenia is reviewed and elucidated at both undergraduate and graduate levels. It is observed that both the quantity and the quality of studies have deteriorated during recent years/decades, thus following similar trends in the developed countries. Presently, no dedicated study of radioactivity is offered within the country. The main reason for this deterioration is a general decline of interest for studying nuclear sciences and the limited need for such specialization in a small country such as Slovenia. (author)

Experimental study of nuclear models. I. Decay schemes and nuclear reactions. II. Muonic x-ray studies. Progress report, October 1, 1974--September 30, 1975

International Nuclear Information System (INIS)

Sheline, R.K.

1975-01-01

Progress on the research on our AT-(40-1)-2434 Contract is summarized for the twelve month contract year beginning October 1, 1974, and ending September 30, 1975. The main emphasis of our research continues to be an experimental study of nuclear models. Some change of emphasis is occurring. In the past, the emphasis has been overwhelmingly nuclear reaction spectroscopy and comparison with theoretical models. This year an increasing percentage of the emphasis (perhaps 25 percent) is on the study of nuclear structure from the view point of muonic x-ray spectroscopy. A list of publications is included. (U.S.)

Levelized Costs for Nuclear, Gas and Coal for Electricity, under the Mexican Scenario

Energy Technology Data Exchange (ETDEWEB)

Palacios, J.C.; Alonso, G.; Ramirez, R.; Gomez, A.; Ortiz, J.; Longoria, L.C.

2004-10-06

In the case of new nuclear power stations, it is necessary to pay special attention to the financial strategy that will be applied, time of construction, investment cost, and the discount and return rate. The levelized cost quantifies the unitary cost of the electricity (the kWh) generated during the lifetime of the nuclear power plant; and allows the immediate comparison with the cost of other alternative technologies. The present paper shows levelized cost for different nuclear technologies and it provides comparison among them as well as with gas and coal electricity plants. For the calculations we applied our own methodology to evaluate the levelized cost considering investment, fuel and operation and maintenance costs, making assumptions for the Mexican market, and taking into account the gas prices projections. The study also shows comparisons using different discount rates (5% and 10%), and some comparisons between our results and an OECD 1998 study. The results are i n good agreement and shows that nuclear option is cost competitive in Mexico on the basis of levelized costs.

Levelized Costs for Nuclear, Gas and Coal for Electricity, under the Mexican Scenario

International Nuclear Information System (INIS)

Palacios, J.C.; Alonso, G.; Ramirez, R.; Gomez, A.; Ortiz, J.; Longoria, L.C.

2004-01-01

In the case of new nuclear power stations, it is necessary to pay special attention to the financial strategy that will be applied, time of construction, investment cost, and the discount and return rate. The levelized cost quantifies the unitary cost of the electricity (the kWh) generated during the lifetime of the nuclear power plant; and allows the immediate comparison with the cost of other alternative technologies. The present paper shows levelized cost for different nuclear technologies and it provides comparison among them as well as with gas and coal electricity plants. For the calculations we applied our own methodology to evaluate the levelized cost considering investment, fuel and operation and maintenance costs, making assumptions for the Mexican market, and taking into account the gas prices projections. The study also shows comparisons using different discount rates (5% and 10%), and some comparisons between our results and an OECD 1998 study. The results are i n good agreement and shows that nuclear option is cost competitive in Mexico on the basis of levelized costs

Improving the description of collective effects within the combinatorial model of nuclear level densities

International Nuclear Information System (INIS)

Hilaire, S.; Girod, M.; Goriely, S.

2011-01-01

The combinatorial model of nuclear level densities has now reached a level of accuracy comparable to that of the best global analytical expressions without suffering from the limits imposed by the statistical hypothesis on which the latter expressions rely. In particular, it provides naturally, non Gaussian spin distribution as well as non equipartition of parities which are known to have a significant impact on cross section predictions at low energies. Our first global model developed in Ref. 1 suffered from deficiencies, in particular in the way the collective effects - both vibrational and rotational - were treated. We have recently improved this treatment using simultaneously the single particle levels and collective properties predicted by a newly derived Gogny interaction, therefore enabling a microscopic description of energy-dependent shell, pairing and deformation effects. In addition, for deformed nuclei, the transition to sphericity is coherently taken into account on the basis of a temperature-dependent Hartree-Fock calculation which provides at each temperature the structure properties needed to build the level densities. This new method is described and shown to give promising preliminary results with respect to available experimental data. (authors)

Table of Half-Lives for Excited Nuclear Levels

Energy Technology Data Exchange (ETDEWEB)

Malmskog, S G

1970-07-15

The knowledge of the half-lives of excited states is often a valuable information in the investigation of the nuclear level structure. The present paper contains a collection of such half-lives being published in the current literature over the period 1967-1970. The data is arranged in increasing order of mass number.

US program for the immobilization of high-level nuclear wastes

International Nuclear Information System (INIS)

Crandall, J.L.

1979-01-01

A program has been developed for long-term management of high-level nuclear waste. The Savannah River Operations Office of the US Department of Energy is acting as the lead office for this program with technical advice from the E.I. du Pont de Nemours and Company. The purpose of the long-term program is to immobilize the DOE high-level waste in forms that act as highly efficient barriers against radionuclide release to the disposal site and to provide technology for similar treatment of commercial high-level waste in case reprocessing of commercial nuclear fuels is ever resumed. Descriptions of existing DOE and commercial wastes, program strategy, program expenditures, development of waste forms, evaluation and selection of waste forms, regulatory aspects of waste form selection, project schedules, and cost estimates for immobilization facilities are discussed

Joliot-Curie nuclear physics school 1983

International Nuclear Information System (INIS)

The 1983 Joliot-Curie school was aimed at reviewing some outstanding aspects of current research in nuclear spectroscopy. The recent developments of high and very high spin states study are presented. The most important experimental methods and explaining concepts concerning the ground states and the first excited levels of nuclei far from beta stability are reviewed. Spin-isospin excitations are dealt with from a theoretical point of view and also for the most outstanding experimental results. At last, basic concepts and limits of the shell model nuclear description are outlined and illustrated [fr

Final disposal of high levels waste and spent nuclear fuel

International Nuclear Information System (INIS)

Gelin, R.

1984-05-01

Foreign and international activities on the final disposal of high-level waste and spent nuclear fuel have been reviewed. A considerable research effort is devoted to development of acceptable disposal options. The different technical concepts presently under study are described in the report. Numerous studies have been made in many countries of the potential risks to future generations from radioactive wastes in underground disposal repositories. In the report the safety assessment studies and existing performance criteria for geological disposal are briefly discussed. The studies that are being made in Canada, the United States, France and Switzerland are the most interesting for Sweden as these countries also are considering disposal into crystalline rocks. The overall time-tables in different countries for realisation of the final disposal are rather similar. Normally actual large-scale disposal operations for high-level wastes are not foreseen until after year 2000. In the United States the Congress recently passed the important Nuclear Waste Policy Act. It gives a rather firm timetable for site-selection and construction of nuclear waste disposal facilities. According to this act the first repository for disposal of commercial high-level waste must be in operation not later than in January 1998. (Author)

Towards more accurate and reliable predictions for nuclear applications

International Nuclear Information System (INIS)

Goriely, S.

2015-01-01

The need for nuclear data far from the valley of stability, for applications such as nuclear astrophysics or future nuclear facilities, challenges the robustness as well as the predictive power of present nuclear models. Most of the nuclear data evaluation and prediction are still performed on the basis of phenomenological nuclear models. For the last decades, important progress has been achieved in fundamental nuclear physics, making it now feasible to use more reliable, but also more complex microscopic or semi-microscopic models in the evaluation and prediction of nuclear data for practical applications. In the present contribution, the reliability and accuracy of recent nuclear theories are discussed for most of the relevant quantities needed to estimate reaction cross sections and beta-decay rates, namely nuclear masses, nuclear level densities, gamma-ray strength, fission properties and beta-strength functions. It is shown that nowadays, mean-field models can be tuned at the same level of accuracy as the phenomenological models, renormalized on experimental data if needed, and therefore can replace the phenomenogical inputs in the prediction of nuclear data. While fundamental nuclear physicists keep on improving state-of-the-art models, e.g. within the shell model or ab initio models, nuclear applications could make use of their most recent results as quantitative constraints or guides to improve the predictions in energy or mass domain that will remain inaccessible experimentally. (orig.)

Experimental nuclear physics

Science.gov (United States)

An earlier study of unusual electromagnetic decays in (sup 86)Zr was extended in order to make comparisons with its isotone (sup 84)Sr and with (sup 84)Zr. The K=14 (t(sub 1/2) = 70 ns) high-spin isomer in (sup 176)W was found to have a 13 percent branch directly to the K=O ground-state band, one of the strongest violations of K-selection rules known. A new program to search for a predicted region of oblate deformation involving neutron deficient isotopes in the Rn/Fr/Ra region was begun. In the area of nuclear astrophysics, as part of a study of the onset of the rp-Process, a set of measurements searching for possible new resonances for (sup 14)O+(alpha) and (sup 17)F+p reactions was completed and a coincidence experiment measuring the (sup 19)F ((sup 3)He,t) (sup 19)Ne(alpha) (sup 15)O and (sup 19)F ((sup 3)He,t) (sup 19)Ne(p) (sup 18)F reactions in order to determine the rates of the (sup 18)F(p,(alpha)) (sup 15)O and (sup 18)F(p,(gamma)) (sup 19)Ne reactions was begun. Experimental measurements of (beta)n(alpha) coincidences from the (sup 15)N(d,p) (sup 16)N((beta)- (nu)) (sup 16)O((alpha)) (sup 12)C reaction have also been completed and are currently being analyzed to determine the rate of the (sup 12)C((alpha),(gamma)) reaction. In the APEX collaboration, we have completed the assembly and testing of two position-sensitive Na barrels which surround the axial silicon detector arrays and serve as the e(sup +) triggers by detecting their back-to-back annihilation quanta were completed. The HI@AGS and RHIC collaborations, construction and implementation activities associated with the space-time-tracker detector and in the design of the central detector for the PHENIX experiment were carried out. Operation of the ESTU tandem accelerator has been reliable, delivering beam on target at terminal voltages as high as 19.3 MV and running for as long as 143 days between tank openings. Fabrication and bench testing of a new negative ion source system have been completed.

Studies in nuclear structure relevant to Astrophysics: theoretical and experimental efforts

International Nuclear Information System (INIS)

Saha Sarkar, Maitreyee

2016-01-01

Experimental and theoretical investigations in the region around doubly magic neutron rich 132 Sn nucleus have recently revealed many intriguing issues concerning some newer aspects of nuclear structure in such exotic environments. These nuclei lie on or close to the path of the astrophysical r-process flow. A glimpse of the implication of these studies on the r-process nucleosynthesis will be discussed. Presently, the Nuclear Physics group in Saha Institute of Nuclear Physics is working for installation of a high-current, low energy Accelerator as the primary component of the Facility for Research in low Energy Nuclear Astrophysics (FRENA), a national facility, at Kolkata. Planning for future experiments has been undertaken for successful utilization of this facility. Implantation technique has been found to be one of the most effective methods to produce isotopically pure targets. We have prepared a few isotopically pure targets using this technique. Being the slowest process of the CNO cycle, study of the 14 N(p, γ) 15 O(Q = 7297 keV) capture reaction is of high astrophysical interest. From an experiment utilizing one of the newly prepared 14 N implanted targets, a preliminary estimate of the lifetime of 6792 keV state in 15 O has been obtained, using Doppler shift attenuation method (DSAM). The sensitivity of the results with respect to the uncertainties in various input quantities has been tested. This endeavour will be helpful to design a better experiment to extract more precise lifetime for this important state

Experimental evaluation of an expert system for nuclear reactor operators

International Nuclear Information System (INIS)

Nelson, W.R.

1984-10-01

The United States Nuclear Regulatory Commission (USNRC) is supporting a program for the experimental evaluation of an expert system for nuclear reactor operators. A prototype expert system, called the Response Tree System, has been developed and implemented at INEL. The Response Tree System is designed to assess the status of a reactor system following an accident and recommend corrective actions to reactor operators. The system is implemented using color graphic displays and is driven by a computer simulation of the reactor system. Control of the system is accomplished using a transparent touch panel. Controlled experiments are being conducted to measure performance differences between operators using the Response Tree System and those not using it to respond to simulated accident situations. This paper summarizes the methodology and results of the evaluation of the Response Tree System, including the quantitative results obtained in the experiments thus far. Design features of the Response Tree System are discussed, and general conclusions regarding the applicability of expert systems in reactor control rooms are presented

PSA Level 2:Scope And Method Of PSA Level 2 For Nuclear Power Plant

International Nuclear Information System (INIS)

Widodo, Surip; Antariksawan, Anhar R.

2001-01-01

A study of scope and method of PSA Level 2 had been conducted. The background of the study is the need to gain the capability to well perform PSA Level 2 for nuclear facilities. This study is a literature survey. The scope of PSA Level 2 consists of generating plant damage states, accident progression analysis, and grouping source terms. Concerning accident progression analysis, several methods are used, among others event tree method, named accident progression event tree (APET) or containment event tree (CET), and fault tree method. The end result of PSA Level 2 is release end states which is grouped into release bins. The results will be used for PSA Level 3

Possibility of combining nuclear level pumping in plasma with lasing in solid

International Nuclear Information System (INIS)

Karamyan, S.A.; Carroll, J.J.

2002-01-01

Nuclear isomers can be used for the storage and release of 'clean' nuclear energy, and the visible schemes are discussed. Resonance between the atomic and nuclear transitions may be manifested in a form of the hybridization of atomic-nuclear excitation at the appropriate case. The nuclear levels - candidates for triggering via atomic transitions are described. A variety of the ionization states and atomic-shell configurations arises in hot plasma generated by the short powerful pulse of laser light. The nonradiative conversion of the ionization energy within atom can be suppressed in the hot-plasma surroundings. Time-scales of different processes in nuclear, atomic and condensed-matter subsystems are compared. The processes of fast ionization in solid, X-ray radiance in plasma, sample melting and recrystallisation may precede nuclear fluorescence. Time-scale shorter 0.1 ns makes this sequence promising for the group excitation of short-lived modes in nuclear subsystem

Survey of ambient electromagnetic and radio-frequency interference levels in nuclear power plants

International Nuclear Information System (INIS)

Kercel, S.W.; Moore, M.R.; Blakeman, E.D.; Ewing, P.D.; Wood, R.T.

1996-11-01

This document reports the results of a survey of ambient electromagnetic conditions in representative nuclear power plants. The U.S. Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research engaged the Oak Ridge National Laboratory (ORNL) to perform these measurements to characterize the electromagnetic interference (EMI) and radio-frequency interference (RFI) levels that can be expected in nuclear power plant environments. This survey is the first of its kind, being based on long-term unattended observations. The data presented in this report were measured at eight different nuclear units and required 14 months to collect. A representative sampling of power plant conditions (reactor type, operating mode, site location) monitored over extended observation periods (up to 5 weeks) were selected to more completely determine the characteristic electromagnetic environment for nuclear power plants. Radiated electric fields were measured over the frequency range of 5 MHz to 8 GHz. Radiated magnetic fields and conducted EMI events were measured over the frequency range of 305 Hz to 5 MHz. Highest strength observations of the electromagnetic ambient environment across all measurement conditions at each site provide frequency-dependent profiles for EMI/RFI levels in nuclear power plants

Overview of experimental work to ensure innovation of nuclear fuel for future advanced PWRs

International Nuclear Information System (INIS)

Zymak, J.; Valach, M.; Hejna, J.

2002-11-01

It is envisaged that advanced nuclear fuel will be operated in high burnup conditions, at a high linear power and at considerable mechanical fuel-cladding interactions. The report gives an overview of experimental work investigating phenomena that will affect APWR fuel, such as the manufacturing technology, thermal properties and safety requirements

Reduction and resource recycling of high-level radioactive wastes through nuclear transmutation with PHITS code

International Nuclear Information System (INIS)

Fujita, Reiko

2017-01-01

In the ImPACT program of the Cabinet Office, programs are underway to reduce long-lived fission products (LLFP) contained in high-level radioactive waste through nuclear transmutation, or to recycle/utilize useful nuclear species. This paper outlines this program and describes recent achievements. This program consists of five projects: (1) separation/recovery technology, (2) acquisition of nuclear transmutation data, (3) nuclear reaction theory model and simulation, (4) novel nuclear reaction control and development of elemental technology, and (5) discussions on process concept. The project (1) develops a technology for dissolving vitrified solid, a technology for recovering LLFP from high-level waste liquid, and a technology for separating odd and even lasers. Project (2) acquires the new nuclear reaction data of Pd-107, Zr-93, Se-79, and Cs-135 using RIKEN's RIBF or JAEA's J-PARC. Project (3) improves new nuclear reaction theory and structural model using the nuclear reaction data measured in (2), improves/upgrades nuclear reaction simulation code PHITS, and proposes a promising nuclear transmutation pathway. Project (4) develops an accelerator that realizes the proposed transmutation route and its elemental technology. Project (5) performs the conceptual design of the process to realize (1) to (4), and constructs the scenario of reducing/utilizing high-level radioactive waste to realize this design. (A.O.)

Computer techniques for experimental work in GDR nuclear power plants with WWER

International Nuclear Information System (INIS)

Stemmler, G.

1985-01-01

Nuclear power plant units with WWER are being increasingly equipped with high-performance, programmable process control computers. There are, however, essential reasons for further advancing the development of computer-aided measuring systems, in particular for experimental work. A special structure of such systems, which is based on the division into relatively rigid data registration and primary handling and into further processing by advanced programming language, has proved useful in the GDR. (author)

Progress in nuclear measuring and experimental techniques by application of microelectronics. 1

International Nuclear Information System (INIS)

Meiling, W.

1984-01-01

In the past decade considerable progress has been made in nuclear measuring and experimental techniques by developing position-sensitive detector systems and widely using integrated circuits and microcomputers for data acquisition and processing as well as for automation of measuring processes. In this report which will be published in three parts those developments are reviewed and demonstrated on selected examples. After briefly characterizing microelectronics, the use of microelectronic elements for radiation detectors is reviewed. (author)

Low-level waste management at the Nuclear Research Center

International Nuclear Information System (INIS)

Montanez, O.; Blanco, D.; Vallarino, V.; Calisto, W.

1986-01-01

A general overview of low-level radioactive waste management at the Nuclear Investigation Centre (CIN) of Uruguay is presented. The CIN is a pilot centre of research and development of techniques for implementing measurements for radioactive waste storage and control. (M.C.K.) [pt

Lead iron phosphate glass as a containment medium for disposal of high-level nuclear waste

International Nuclear Information System (INIS)

Boatner, L.A.; Sales, B.C.

1989-01-01

This patent describes lead-iron phosphate glasses containing a high level of Fe 2 O 3 for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste, a highly corrosion resistant, homogeneous, easily processed glass can be formed. For corroding solutions at 90 0 C, with solution pH values in the range between 5 and 9, the corrosion rate of the lead-iron phosphate nuclear waste glass is at least 10 2 to 10 3 times lower than the corrosion rate of a comparable borosilicate nuclear waste glass. The presence of Fe 2 O 3 in forming the lead-iron phosphate glass is critical. The lead-iron phosphate waste glasses can be prepared with minimal modification of the technology developed for processing borosilicate glass nuclear wasteforms

Global and local level density models

International Nuclear Information System (INIS)

Koning, A.J.; Hilaire, S.; Goriely, S.

2008-01-01

Four different level density models, three phenomenological and one microscopic, are consistently parameterized using the same set of experimental observables. For each of the phenomenological models, the Constant Temperature Model, the Back-shifted Fermi gas Model and the Generalized Superfluid Model, a version without and with explicit collective enhancement is considered. Moreover, a recently published microscopic combinatorial model is compared with the phenomenological approaches and with the same set of experimental data. For each nuclide for which sufficient experimental data exists, a local level density parameterization is constructed for each model. Next, these local models have helped to construct global level density prescriptions, to be used for cases for which no experimental data exists. Altogether, this yields a collection of level density formulae and parameters that can be used with confidence in nuclear model calculations. To demonstrate this, a large-scale validation with experimental discrete level schemes and experimental cross sections and neutron emission spectra for various different reaction channels has been performed

Seismic fragility levels of nuclear power plant equipment

International Nuclear Information System (INIS)

Bandyopadhyay, K.K.; Hofmayer, C.H.

1987-01-01

Seismic fragility levels of safety-related electrical and mechanical equipment used in nuclear power plants are discussed. The fragility level is defined as the vibration level corresponding to initiation of equipment malfunctions. The test response spectrum is used as a measure of this vibration level. The fragility phenomenon of an equipment is represented by a number of response spectra corresponding to various failure modes. Analysis methods are described for determination of the fragility level by use of existing test data. Useful conversion factors are tabulated to transform test response spectra from one damping value to another. Results are presented for switch-gears and motor control centers. The capacity levels of these equipment assemblies are observed to be limited by malfunctioning of contactors, motor starters, relays and/or switches. The applicability of the fragility levels, determined in terms of test response spectra, to Seismic Margin Studies and Probabilistic Risk Assessments is discussed and specific recommendations are provided

Two-stage nuclear refrigeration with enhanced nuclear moments

International Nuclear Information System (INIS)

Hunik, R.

1979-01-01

Experiments are described in which an enhanced nuclear system is used as a precoolant for a nuclear demagnetisation stage. The results show the promising advantages of such a system in those circumstances for which a large cooling power is required at extremely low temperatures. A theoretical review of nuclear enhancement at the microscopic level and its macroscopic thermodynamical consequences is given. The experimental equipment for the implementation of the nuclear enhanced refrigeration method is described and the experiments on two-stage nuclear demagnetisation are discussed. With the nuclear enhanced system PrCu 6 the author could precool a nuclear stage of indium in a magnetic field of 6 T down to temperatures below 10 mK; this resulted in temperature below 1 mK after demagnetisation of the indium. It is demonstrated that the interaction energy between the nuclear moments in an enhanced nuclear system can exceed the nuclear dipolar interaction. Several experiments are described on pulsed nuclear magnetic resonance, as utilised for thermometry purposes. It is shown that platinum NMR-thermometry gives very satisfactory results around 1 mK. The results of experiments on nuclear orientation of radioactive nuclei, e.g. the brute force polarisation of 95 NbPt and 60 CoCu, are presented, some of which are of major importance for the thermometry in the milli-Kelvin region. (Auth.)

Low-temperature nuclear orientation

International Nuclear Information System (INIS)

Stone, N.J.; Postma, H.

1986-01-01

This book comprehensively surveys the many aspects of the low temperature nuclear orientation method. The angular distribution of radioactive emissions from nuclei oriented by hyperfine interactions in solids, is treated experimentally and theoretically. A general introductory chapter is followed by formal development of the theory of the orientation process and the anisotropic emission of decay products from oriented nuclei, applied to radioactive decay and to reactions. Five chapters on applications to nuclear physics cover experimental studies of alpha, beta and gamma emission, nuclear moment measurement and level structure information. Nuclear orientation studies of parity non-conservation and time reversal asymmetry are fully described. Seven chapters cover aspects of hyperfine interactions, magnetic and electric, in metals, alloys and insulating crystals, including ordered systems. Relaxation phenomena and the combined technique of NMR detection using oriented nuclei are treated at length. Chapters on the major recent development of on-line facilities, giving access to short lived nuclei far from stability, on the use of nuclear orientation for thermometry below 1 Kelvin and on technical aspects of the method complete the main text. Extensive appendices, table of relevant parameters and over 1000 references are included to assist the design of future experiments. (Auth.)

Nuclear level repulsion, order vs. chaos and conserved quantum numbers

International Nuclear Information System (INIS)

Garrett, J.D.

1995-01-01

A statistical analysis of the distribution of level spacings for states with the same angular momentum and parity is described in which the average spacing is calculated for the total ensemble. Though the resulting distribution of level spacings for states of deformed nuclei with Z = 62-75 and A = 155-185 is the closest to that of a Poisson distribution yet obtained for nuclear levels, significant deviations are observed for small level spacings. Many, but not all, of the very closely-spaced levels have K-values differing by several units. (orig.)

Nuclear Criticality Experimental Research Center (NCERC) Overview

Energy Technology Data Exchange (ETDEWEB)

Goda, Joetta Marie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Grove, Travis Justin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hayes, David Kirk [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Myers, William L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Sanchez, Rene Gerardo [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-03-03

The mission of the National Criticality Experiments Research Center (NCERC) at the Device Assembly Facility (DAF) is to conduct experiments and training with critical assemblies and fissionable material at or near criticality in order to explore reactivity phenomena, and to operate the assemblies in the regions from subcritical through delayed critical. One critical assembly, Godiva-IV, is designed to operate above prompt critical. The Nuclear Criticality Experimental Research Center (NCERC) is our nation’s only general-purpose critical experiments facility and is only one of a few that remain operational throughout the world. This presentation discusses the history of NCERC, the general activities that makeup work at NCERC, and the various government programs and missions that NCERC supports. Recent activities at NCERC will be reviewed, with a focus on demonstrating how NCERC meets national security mission goals using engineering fundamentals. In particular, there will be a focus on engineering theory and design and applications of engineering fundamentals at NCERC. NCERC activities that relate to engineering education will also be examined.

Status of the high-level nuclear waste disposal program in Japan

International Nuclear Information System (INIS)

Uematsu, K.

1985-01-01

The Japan Atomic Energy Commission (JAEC) initiated a high-level radioactive waste disposal program in 1976. Since then, the Advisory Committee on Radioactive Waste Management of JAEC has revised the program twice. The latest revision was issued in 1984. The committee recommended a four-phase program and the last phase calls for the beginning of emplacement of the high-level nuclear waste into a selected repository in the Year 2000. The first phase is already completed, and the second phase of this decade calls for the selection of a candidate disposal site and the conducting of the RandD of waste disposal in an underground research laboratory and in a hot test facility. This paper covers the current status of the high-level nuclear waste disposal program in Japan

Temperature and level measurements realized for Nuclear Safety Level Improvement of Slovak NPPs

International Nuclear Information System (INIS)

Badiar, S.; Slanina, M.; Stanc, S.; Golan, P.; Krupa, J.

2001-01-01

Process of continual safety improvement in the individual Slovak nuclear power plants has been in progress since the beginning of nineties with the objective to upgrade the safety level of units in operation up to the European standards. In the framework of these activities, safety instrumentation systems with 1E qualification for the control of WWER reactor coolant systems were built and added. Methods for implementation of safety instrumentation systems for monitoring temperature and level in reactor coolant systems in the particular plants in Slovakia are presented showing the objectives and methods of their implementation. (Authors)

Analysis of opinion about nuclear energy and sustainability in a graduate level population

International Nuclear Information System (INIS)

Meza L, C.D.; Arredondo S, C.

2007-01-01

The Mexican society has a modest knowledge of the nuclear energy, even at the participant students of superior education level in this survey is finds a scarce compression with regard to their obtaining, use and manage. As a result of the lack of interest of the same society and at the problems that know each other like they are: the pollutants that it produces those nuclear waste and the possible use or warlike end, a fear is believed about this energy type. In the Superior School of Physics and Mathematics there is the possibility to make studies so much at master degree level in the one fear of the nuclear energy and the applications of the same one in peaceful uses. However, particularly the studies at master level seem to be immersed in a crisis that requires of different supports to be resolved. For all it previous was thought in carrying out a survey inside a student population with superior level to know the opinion and the knowledge on the nuclear energy in Mexico. In this work the results of the survey are analyzed with the purpose of to determine which is the knowledge of the community mentioned regarding the other energy types, the impact that they have these in the environment, the sustenance of the same ones and in particular on knowledge about the nuclear energy considering the aspects before mentioned. With base had said analysis settles down that the interviewed community knows very little about the nuclear energy but they show interest to study and to obtain bigger information about the same one, for what is very important to diffuse but and better information on the nuclear energy to the population's strata, because it is of supposing that the rest of the population has erroneous information on the nuclear energy. In particular for the community of the Superior School of Physics and Mathematics the diffusion of all the benefits of the peaceful applications of the nuclear energy, including the capacity to generate enormous quantities and energy

Proposed experimental test of Bell's inequality in nuclear beta decay

International Nuclear Information System (INIS)

Skalsey, M.

1986-01-01

A β decay experiment is proposed for testing Bell's inequality, related to hidden-variables alternatives to quantum mechanics. The experiment uses Mott scattering for spin polarization analysis of internal conversion electrons. Beta-decay electrons, in cascade with the conversion electrons, are longitudinally polarized due to parity violation in the weak interaction. So simply detecting the β electron direction effectively measures the spin. A two-particle spin-spin correlation can thus be investigated and related, within certain assumptions, to Bell's inequality. The example of 203 Hg decay is used for a calculation of expected results. Specific problems related to nuclear structure and experimental inconsistencies are also discussed

External radiation levels in installations of nuclear technology center

International Nuclear Information System (INIS)

Maletta, Paulo Guilherme M.; Filipetto, Joao; Wakabayashi, Tetsuaki; Silva, Teogenes A. da

2005-01-01

The radiological protection is a basic activity of nuclear technology center so that can carry through its activities with security, having to be planned and executed with total effectiveness. One of the basic tools of the radiological protection is the adoption of monitoring programs, that have as objective generality to evaluate the radiological conditions of the workstation and to assure that these conditions are acceptable safe for the displayed individuals, either workers or members of the public, as established in the basic norms of radiological protection. The Centro de Desenvolvimento da Tecnologia Nuclear - CDTN, first institution in Brazil, created in 1952 to entirely dedicate the related works to the nuclear area, to own 39 building, of which they are kept the Triga Reactor, Irradiation Gamma Laboratory, Reject Laboratory, Calibration Dosemeters Laboratory and others. In such installations, radioactive materials are produced, handled, processed and stored, being necessary the levels of external radiation ambient monitoring. As part of the radioprotection plan, monitoring 63 points on strategically located in the external areas to the building of CDTN, using characterized and calibrated thermoluminescence dosemeters. This work describes the dose distribution of the points, the doses evaluation procedure and the 4 results carried through between 2001 and 2004. The data demonstrate the attendance to the level of security established in the basic norm, what it contributed for the operation licensing of to the IBAMA. (author)

What are Spent Nuclear Fuel and High-Level Radioactive Waste?

International Nuclear Information System (INIS)

2002-01-01

Spent nuclear fuel and high-level radioactive waste are materials from nuclear power plants and government defense programs. These materials contain highly radioactive elements, such as cesium, strontium, technetium, and neptunium. Some of these elements will remain radioactive for a few years, while others will be radioactive for millions of years. Exposure to such radioactive materials can cause human health problems. Scientists worldwide agree that the safest way to manage these materials is to dispose of them deep underground in what is called a geologic repository

Can Experimental Scientists, Data Evaluators and Compilers, and Nuclear Data Users Understand One Another?

Energy Technology Data Exchange (ETDEWEB)

Usachev, L. N. [Institute of Physics and Energetics, Obninsk, USSR (Russian Federation)

1966-07-01

The International Atomic Energy Agency organizes conferences on a wide variety of scientific subjects, all of which are of fundamental importance for the development of nuclear power. These include the technology of fuel elements, their stability in neutron fields, and chemical reprocessing as well as reactor physics, mathematical computational methods and the problems of protection and dosimetry. The problem of microscopic nuclear data, an essential aspect of reactor work, is just one of these many subjects. On the other hand, it should be remembered that the possibility of releasing nuclear energy was established in the first place by obtaining nuclear data on the fission process occurring in the uranium nucleus following the capture of a neutron and on the escape of the 2-3 secondary fission neutrons. In early nuclear power work the information provided by nuclear data was of considerable, even of decisive, importance. For example, the information available on the neutron balance in fast reactors showed that such reactors could operate as breeders and thus that it was worth while developing them. Strictly speaking, it is of course difficult to speak of a knowledge of nuclear data at this early period. It is perhaps more accurate to speak of the understanding of and the feeling for such data which grew up on the basis of the existing physical ideas on the fission of the nucleus, radiative capture and neutron scattering. Experimental data were very scanty but for that reason they were particularly valuable.

Can Experimental Scientists, Data Evaluators and Compilers, and Nuclear Data Users Understand One Another?

International Nuclear Information System (INIS)

Usachev, L.N.

1966-01-01

The International Atomic Energy Agency organizes conferences on a wide variety of scientific subjects, all of which are of fundamental importance for the development of nuclear power. These include the technology of fuel elements, their stability in neutron fields, and chemical reprocessing as well as reactor physics, mathematical computational methods and the problems of protection and dosimetry. The problem of microscopic nuclear data, an essential aspect of reactor work, is just one of these many subjects. On the other hand, it should be remembered that the possibility of releasing nuclear energy was established in the first place by obtaining nuclear data on the fission process occurring in the uranium nucleus following the capture of a neutron and on the escape of the 2-3 secondary fission neutrons. In early nuclear power work the information provided by nuclear data was of considerable, even of decisive, importance. For example, the information available on the neutron balance in fast reactors showed that such reactors could operate as breeders and thus that it was worth while developing them. Strictly speaking, it is of course difficult to speak of a knowledge of nuclear data at this early period. It is perhaps more accurate to speak of the understanding of and the feeling for such data which grew up on the basis of the existing physical ideas on the fission of the nucleus, radiative capture and neutron scattering. Experimental data were very scanty but for that reason they were particularly valuable

Transport of Spent Nuclear Fuels, High and Intermediate Level Wastes: A Continuous Challenge

International Nuclear Information System (INIS)

Otton, C.; Blachet, L.

2009-01-01

For more than 45 years TN International has been involved in the radioactive materials transportation field. Since the beginning the used nuclear fuel transportation has been its core business. During all these years TN International, now part of AREVA, has been able to anticipate and fulfil the needs for new transport or storage casks design to fit the nuclear industry evolutions. A whole fleet of casks able to transport all the materials of the nuclear fuel cycle has been developed. In this presentation we will focus on the casks for the spent fuel, high level waste and intermediate level waste transportation. Answering to the constant evolution of the nuclear industry transport needs is a challenge that TN International faces routinely. Concerning the spent nuclear fuel transportation, TN International has developed in the early 80's a fleet of TN12 type casks fitted with several types of baskets able to safely transport all the spent fuel from the nuclear power plant or the research laboratories to AREVA La Hague plant. The current challenge is the design of a new transport cask generation taking into account the needs of the industry for the next 30 years. The replacement of the TN12 cask generation is to be scheduled as the regulations have changed and the fuel characteristics have evolved. The new generation of casks will take into account all the technical evolutions made during the TN12 thirty years of use. MOX spent fuel has now its dedicated cask: the TN112 which certificate of approval has been obtained in July 2008. This cask is able to transport 12 MOX spent fuel elements with a short cooling time. The first loading of the cask has been performed in 2008 in the EDF nuclear power plant of Saint-Laurent-des-Eaux. Concerning the high level waste such as the La Hague vitrified residues a whole fleet of casks has been developed such as the TN 28 VT dedicated to transport, the TN81 and TN85 dedicated to transport and storage. These casks have permitted the

[Experimental nuclear physics]. Final report

International Nuclear Information System (INIS)

1991-04-01

This is the final report of the Nuclear Physics Laboratory of the University of Washington on work supported in part by US Department of Energy contract DE-AC06-81ER40048. It contains chapters on giant dipole resonances in excited nuclei, nucleus-nucleus reactions, astrophysics, polarization in nuclear reactions, fundamental symmetries and interactions, accelerator mass spectrometry (AMS), ultra-relativistic heavy ions, medium energy reactions, work by external users, instrumentation, accelerators and ion sources, and computer systems. An appendix lists Laboratory personnel, a Ph. D. degree granted in the 1990-1991 academic year, and publications. Refs., 41 figs., 7 tabs

[Experimental nuclear physics]. Final report

Energy Technology Data Exchange (ETDEWEB)

NONE

1991-04-01

This is the final report of the Nuclear Physics Laboratory of the University of Washington on work supported in part by US Department of Energy contract DE-AC06-81ER40048. It contains chapters on giant dipole resonances in excited nuclei, nucleus-nucleus reactions, astrophysics, polarization in nuclear reactions, fundamental symmetries and interactions, accelerator mass spectrometry (AMS), ultra-relativistic heavy ions, medium energy reactions, work by external users, instrumentation, accelerators and ion sources, and computer systems. An appendix lists Laboratory personnel, a Ph. D. degree granted in the 1990-1991 academic year, and publications. Refs., 41 figs., 7 tabs.

Nuclear power training programmes in Spain

International Nuclear Information System (INIS)

Tanarro, A.; Izquierdo, L.

1977-01-01

The introduction of nuclear power in Spain is developing very rapidly. At present 1.1GW(e) are installed in Spain and this is expected to increase to 8GW(e) in 1980 and to 28GW(e) in 1990. Spanish industry and technology are also rapidly increasing their participation in building nuclear stations, in manufacturing the necessary components and in the activities related to the nuclear fuel cycle. All of this requires properly trained personnel, which is estimated to become approximately 1200 high-level technicians, 1100 medium-level technicians and 1500 technical assistants by 1980. This personnel is trained: (a) in engineering schools; (b) in the Nuclear Studies Institute; (c) in the electric companies with nuclear programmes. The majority of the high-level engineering schools in the country include physics and basic nuclear technology courses in their programmes. Some of them have an experimental low-power nuclear reactor. The Nuclear Studies Institute is an official organism dependent on the Nuclear Energy Commission and responsible, among other subjects, for training personnel for the peaceful use and development of nuclear energy in the country. The electric companies also participate in training personnel for future nuclear stations and they plan to have advanced simulators of PWR and BWR type stations for operator training. The report deals with the personnel requirement forecasts and describes the training programmes. (author)

Experimental test of nuclear magnetization distribution and nuclear structure models

International Nuclear Information System (INIS)

Beirsdorfer, P; Crespo-Lopez-Urrutia, J R; Utter, S B.

1999-01-01

Models exist that ascribe the nuclear magnetic fields to the presence of a single nucleon whose spin is not neutralized by pairing it up with that of another nucleon; other models assume that the generation of the magnetic field is shared among some or all nucleons throughout the nucleus. All models predict the same magnetic field external to the nucleus since this is an anchor provided by experiments. The models differ, however, in their predictions of the magnetic field arrangement within the nucleus for which no data exist. The only way to distinguish which model gives the correct description of the nucleus would be to use a probe inserted into the nucleus. The goal of our project was to develop exactly such a probe and to use it to measure fundamental nuclear quantities that have eluded experimental scrutiny. The need for accurately knowing such quantities extends far beyond nuclear physics and has ramifications in parity violation experiments on atomic traps and the testing of the standard model in elementary particle physics. Unlike scattering experiments that employ streams of free particles, our technique to probe the internal magnetic field distribution of the nucleus rests on using a single bound electron. Quantum mechanics shows that an electron in the innermost orbital surrounding the nucleus constantly dives into the nucleus and thus samples the fields that exist inside. This sampling of the nucleus usually results in only minute shifts in the electron s average orbital, which would be difficult to detect. By studying two particular energy states of the electron, we can, however, dramatically enhance the effects of the distribution of the magnetic fields in the nucleus. In fact about 2% of the energy difference between the two states, dubbed the hyperfine splitting, is determined by the effects related to the distribution of magnetic fields in the nucleus, A precise measurement of this energy difference (better than 0.01%) would then allow us to place

An aerial radiological survey of the Saxton Nuclear Experimental Corporation facility and surrounding area, Saxton, Pennsylvania

International Nuclear Information System (INIS)

Hoover, R.A.

1991-10-01

An aerial radiological survey was conducted during the period July 5 to 22, 1989, over an 83-square kilometer (32-square-mile) area surrounding the Saxton Nuclear Experimental Corporation (SNEC) facility which is owned by General Public Utilities and located near Saxton, Pennsylvania. The survey was conducted at a nominal altitude of 61 meters (200 feet) with line spacings of 91 meters (300 feet). A contour map of the terrestrial gamma exposure rate extrapolated to 1 meter above ground level (AGL) was prepared and overlaid on an aerial photograph and a set of United States Geological Survey (USGS) topographic maps of the area. The terrestrial exposure rates varied from about 9 to 11 microroentgens per hour (μR/h) over most of the survey area. The levels over the SNEC family did not differ from the exposure rates seen over the entire survey area. Cesium-137 (Cs-137) levels typical of worldwide fallout deposition were detected throughout the surveyed area. No other trends of Cs-137 were observed. Soil samples and pressurized ion chamber measurements were obtained at six locations within the survey boundaries to support the aerial data

First Krakow-Berlin workshop on nuclear physics. Slide report

International Nuclear Information System (INIS)

Styczen, J.; Maier, K.H.

1992-01-01

In this workshop new experimental and theoretical results in nuclear spectroscopy are presented. For several nuclei new data: energy level schemes, electromagnetic transitions, quadrupole moments, and nuclear deformation parameters are presented. New nuclei excitation methods and the new detector for the OSIRIS spectrometer are also discussed

First Krakow-Berlin workshop on nuclear physics. Slide report

Energy Technology Data Exchange (ETDEWEB)

Styczen, J. [comp.] [Institute of Nuclear Physics, Cracow (Poland); Maier, K.H. [comp.] [Hahn-Meitner-Institut Berlin GmbH (Germany)

1992-12-31

In this workshop new experimental and theoretical results in nuclear spectroscopy are presented. For several nuclei new data: energy level schemes, electromagnetic transitions, quadrupole moments, and nuclear deformation parameters are presented. New nuclei excitation methods and the new detector for the OSIRIS spectrometer are also discussed.

Lead-iron phosphate glass as a containment medium for the disposal of high-level nuclear wastes

Science.gov (United States)

Boatner, L.A.; Sales, B.C.

1984-04-11

Disclosed are lead-iron phosphate glasses containing a high level of Fe/sub 2/O/sub 3/ for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste

Nuclear level density of 166Er with static deformation

International Nuclear Information System (INIS)

Nasrabadi, M.N.

2006-01-01

The level densities of 166 Er is calculated using the microscopic theory of interacting fermions and is compared with experimental. It is concluded that the data can be reproduced with level density formalism for nuclei with static deformation

Modeling by GASP-IV simulation of high-level nuclear waste disposal

International Nuclear Information System (INIS)

Kurstedt, H.A. Jr.; DePorter, E.L.; Turek, J.L.; Funk, S.K.; Rasbach, C.E.

1981-01-01

High-level nuclear waste generated by defense-oriented and commercial nuclear energy activities are to be stored ultimately in underground repositories. Research continues on the waste-form and waste-form processing. DOE managers must coordinate the results of this research, the capacities and availability times of the permanent geologic storage repositories, and the capacities and availability times of interim storage facilities (pending availability of permanent repositories). Comprehensive and active DOE program-management information systems contain predicted generation of nuclear wastes from defense and commercial activities; milestones on research on waste-forms; and milestones on research and development, design, acquisition, and construction of facilities and repositories. A GASP IV simulation model is presented which interfaces all of these data. The model accepts alternate management decisions; relates all critical milestones, all research and development data, and the generation of waste nuclear materials; simulates the passage of time; then, predicts the impact of those alternate decisions on the availability of storage capacity for waste nuclear materials. 3 references, 3 figures

Level densities in nuclear physics

International Nuclear Information System (INIS)

Beckerman, M.

1978-01-01

In the independent-particle model nucleons move independently in a central potential. There is a well-defined set of single- particle orbitals, each nucleon occupies one of these orbitals subject to Fermi statistics, and the total energy of the nucleus is equal to the sum of the energies of the individual nucleons. The basic question is the range of validity of this Fermi gas description and, in particular, the roles of the residual interactions and collective modes. A detailed examination of experimental level densities in light-mass system is given to provide some insight into these questions. Level densities over the first 10 MeV or so in excitation energy as deduced from neutron and proton resonances data and from spectra of low-lying bound levels are discussed. To exhibit some of the salient features of these data comparisons to independent-particle (shell) model calculations are presented. Shell structure is predicted to manifest itself through discontinuities in the single-particle level density at the Fermi energy and through variatons in the occupancy of the valence orbitals. These predictions are examined through combinatorial calculations performed with the Grover [Phys. Rev., 157, 832(1967), 185 1303(1969)] odometer method. Before the discussion of the experimenta results, statistical mechanical level densities for spherical nuclei are reviewed. After consideration of deformed nuclei, the conclusions resulting from this work are drawn. 7 figures, 3 tables

experimental implementation of single-phase, three-level, sinusoidal

African Journals Online (AJOL)

Page 1 ... of many multilevel inverter configurations. This paper presents an experimental report of a simplified topology for single-phase, SPWM, three-level voltage source inverter wit R-L load. To keep the power circuit ... employed in many industrial applications such as variable speed drives, uninterruptible power sup-.

Unified model of nuclear mass and level density formulas

International Nuclear Information System (INIS)

Nakamura, Hisashi

2001-01-01

The objective of present work is to obtain a unified description of nuclear shell, pairing and deformation effects for both ground state masses and level densities, and to find a new set of parameter systematics for both the mass and the level density formulas on the basis of a model for new single-particle state densities. In this model, an analytical expression is adopted for the anisotropic harmonic oscillator spectra, but the shell-pairing correlation are introduced in a new way. (author)

Improved predictions of nuclear data: A continued challenge in astrophysics

International Nuclear Information System (INIS)

Goriely, S.

2001-01-01

Although important effort has been devoted in the last decades to measure reaction cross sections and decay half-lives of interest in astrophysics, most of the nuclear astrophysics applications still require the use of theoretical predictions to estimate experimentally unknown rates. The nuclear ingredients to the reaction or weak interaction models should preferentially be estimated from microscopic or semi-microscopic global predictions based on sound and reliable nuclear models which, in turn, can compete with more phenomenological highly-parametrized models in the reproduction of experimental data. The latest developments made in deriving the nuclear inputs of relevance in astrophysics applications are reviewed. It mainly concerns nuclear structure properties (atomic masses, deformations, radii, etc...), nuclear level densities, nucleon and α-optical potentials, γ-ray and Gamow-Teller strength functions

Future health physics prospects in high-level nuclear waste management

International Nuclear Information System (INIS)

Waite, D.A.; Mayberry, J.J.

1986-01-01

The objective of this presentation is to provide an overview of health physics activities anticipated to be required at a high-level nuclear waste repository and to project the numbers of health physics personnel expected to be required to carry out these activities. Health physics personnel receiving consideration in the projections include the health physics manager, shift supervisors, area supervisors, health physicists, and technologists. Phases of the repository addressed are construction, operation, retrieval, and decommissioning. Specific topics discussed in the process of developing the projections are: (a) the basic features of a geologic repository, (b) the staffing requirements of such a repository, (c) health physics involvement in repository operations, and (d) the anticipated schedule for operation of repositories in the United States. A quantitative assessment of future health physics prospects in high-level nuclear waste management is included

Siting high-level nuclear waste repositories: A progress report for Rhode Island

International Nuclear Information System (INIS)

Frohlich, R.K.; Vild, B.F.

1986-03-01

In this booklet, we will not try to argue the pros and cons of nuclear power or weapons production. We will focus instead on the issue of nuclear waste disposal. With the passage of the Nuclear Waste Policy Act (NWPA) of 1982, the US Congress and the President charged federal and state regulators with the responsibility of settling that issue by the end of this century - with extensive public involvement. This booklet, now in its second printing, is designed to explain the nature of ''high-level'' nuclear waste, the essential criteria for its safe and permanent disposal, and Rhode Island's participation in the federal repository program. It has been funded from a USDOE grant derived from a utility-financed Nuclear Waste Fund established under the NWPA. 17 refs., 10 figs., 2 tabs

Experimental investigation and modelling of tritium washout by precipitation in the area of the nuclear power plant of Paks, Hungary

International Nuclear Information System (INIS)

Koello, Z.; Palcsu, L.; Major, Z.; Papp, L.; Molnar, M.; Ranga, T.; Dombovari, P.; Manga, L.

2011-01-01

Tritium occurs in nature in trace amounts, but its concentration is changing due to natural and artificial sources. Studies focusing on natural tritium have to take into account the effect of artificial sources. Also, the impact of tritium is an important issue in environmental protection, e.g. in connection with the emissions from nuclear power plants. The present work focuses on the rain washout of tritium emitted from the Paks nuclear power plant in Hungary. Rainwater collectors were placed around the plant and after a period of precipitation, rainwater was collected and analysed for tritium content. Samples were analysed using low-level liquid scintillation counting, with some also subject to the more accurate 3 He ingrowth method. The results clearly show the trace of the tritium plume emitted from the plant; however, values are only about one order of magnitude higher than environmental background levels. A washout model was devised to estimate the distribution of tritium around the plant. The model gives slightly higher concentrations than those measured in the field, but in general the agreement is satisfactory. The modelled values demonstrate that the effect of the plant on rainwater tritium levels is negligible over a distance of some kilometres. - Research highlights: →The rainwater around a nuclear power plant was collected with a special rainwater collector →The rainwater after a rain event was analysed for tritium with LSC and with the helium ingrowth method. →The trace of the tritium plume is clearly detectable in the rainwater. →The agreement between a reversible washout model and experimental data is satisfactory. →According to the model the tritium plume is hardly detectable over some kilometers from the plant

Neutron-capture gamma-ray study of levels in 135Ba and description of nuclear levels in the interacting-boson-fermion model

International Nuclear Information System (INIS)

Chrien, R.E.; Koene, B.K.S.; Stelts, M.L.; Meyer, R.A.; Brant, S.; Paar, V.; Lopac, V.

1993-01-01

We have performed neutron-capture gamma-ray studies on natural and enriched targets of 134 Ba in order to investigate the nuclear levels of 135 Ba. The low-energy level spectra were compared with the calculations using the interacting-boson-fermion model (IBFM) and the cluster-vibration model. The level densities up to 5 MeV that are calculated within the IBFM are in accordance with the constant temperature Fermi gas model. From the spin distribution we have determined the corresponding spin cutoff parameter σ and compared it to the prediction from nuclear systematics

Experimental simulation study on hydraulic behavior of the main heat exchanger of Daqing 200 MW nuclear heating reactor

International Nuclear Information System (INIS)

Jiang Shengyao; Zhang Youjie; Jia Haijun; Bo Jinhai; Hong Liuming; Bo Hanliang; Liu Zhiyong

1997-07-01

The hydraulic behavior of the main heat exchanger of Daqing 200 MW nuclear heating reactor is studied through a 1:2.33 test model. The design and other feature of the test model is described. The experimental results show that the flow resistance coefficient of the heat exchanger becomes self-simulation when Reynolds number is greater than 5000. The value of flow resistance coefficient at self-simulation condition and the distribution of pressure drop in the heat exchanger are given through experiment. The option design to reduce flow resistance is proposed. The designed and experimental value for the flow resistance coefficient are in good agreement. The variation of system parameters during flow excursion was described. The experimental results are of great significant for the final design of the main heat exchanger of Daqing 200 MW nuclear heating reactor. (2 refs., 5 figs., 1 tab.)

Differentiated influences of benefit and risk perceptions on nuclear power acceptance according to acceptance levels. Evidence from Korea

International Nuclear Information System (INIS)

Roh, Seungkook; Lee Jinwon

2017-01-01

The perceived benefit and risk of nuclear power generation have received considerable attention as determinants of the public's nuclear power acceptance. However, the contingency of the relative importance of these benefit and risk has been less explored. Using Korea as an example, this study explores the possibility that the relative importance of perceived benefit and risk on nuclear power acceptance depends on acceptance levels. Our results from latent class analysis and multinomial probit show that, in determining whether an individual shows a moderate level of nuclear power acceptance rather than a low level, perceived risk plays a dominant role compared to perceived benefit; however, regarding whether he/she shows a high level of nuclear power acceptance rather than a moderate level, this relative importance is reversed. These results carry practical implications for risk governance of nuclear power, particularly with regard to communication with the public. (author)

Nuclear size is sensitive to NTF2 protein levels in a manner dependent on Ran binding

Science.gov (United States)

Vuković, Lidija D.; Jevtić, Predrag; Zhang, Zhaojie; Stohr, Bradley A.; Levy, Daniel L.

2016-01-01

ABSTRACT Altered nuclear size is associated with many cancers, and determining whether cancer-associated changes in nuclear size contribute to carcinogenesis necessitates an understanding of mechanisms of nuclear size regulation. Although nuclear import rates generally positively correlate with nuclear size, NTF2 levels negatively affect nuclear size, despite the role of NTF2 (also known as NUTF2) in nuclear recycling of the import factor Ran. We show that binding of Ran to NTF2 is required for NTF2 to inhibit nuclear expansion and import of large cargo molecules in Xenopus laevis egg and embryo extracts, consistent with our observation that NTF2 reduces the diameter of the nuclear pore complex (NPC) in a Ran-binding-dependent manner. Furthermore, we demonstrate that ectopic NTF2 expression in Xenopus embryos and mammalian tissue culture cells alters nuclear size. Finally, we show that increases in nuclear size during melanoma progression correlate with reduced NTF2 expression, and increasing NTF2 levels in melanoma cells is sufficient to reduce nuclear size. These results show a conserved capacity for NTF2 to impact on nuclear size, and we propose that NTF2 might be a new cancer biomarker. PMID:26823604

Isomer depletion as experimental evidence of nuclear excitation by electron capture

Science.gov (United States)

Chiara, C. J.; Carroll, J. J.; Carpenter, M. P.; Greene, J. P.; Hartley, D. J.; Janssens, R. V. F.; Lane, G. J.; Marsh, J. C.; Matters, D. A.; Polasik, M.; Rzadkiewicz, J.; Seweryniak, D.; Zhu, S.; Bottoni, S.; Hayes, A. B.; Karamian, S. A.

2018-02-01

The atomic nucleus and its electrons are often thought of as independent systems that are held together in the atom by their mutual attraction. Their interaction, however, leads to other important effects, such as providing an additional decay mode for excited nuclear states, whereby the nucleus releases energy by ejecting an atomic electron instead of by emitting a γ-ray. This ‘internal conversion’ has been known for about a hundred years and can be used to study nuclei and their interaction with their electrons. In the inverse process—nuclear excitation by electron capture (NEEC)—a free electron is captured into an atomic vacancy and can excite the nucleus to a higher-energy state, provided that the kinetic energy of the free electron plus the magnitude of its binding energy once captured matches the nuclear energy difference between the two states. NEEC was predicted in 1976 and has not hitherto been observed. Here we report evidence of NEEC in molybdenum-93 and determine the probability and cross-section for the process in a beam-based experimental scenario. Our results provide a standard for the assessment of theoretical models relevant to NEEC, which predict cross-sections that span many orders of magnitude. The greatest practical effect of the NEEC process may be on the survival of nuclei in stellar environments, in which it could excite isomers (that is, long-lived nuclear states) to shorter-lived states. Such excitations may reduce the abundance of the isotope after its production. This is an example of ‘isomer depletion’, which has been investigated previously through other reactions, but is used here to obtain evidence for NEEC.

Lead-iron phosphate glass: a stable storage medium for high-level nuclear waste

International Nuclear Information System (INIS)

Sales, B.C.; Boatner, L.A.

1984-01-01

Results are presented which show that lead-iron phosphate glasses are a promising new waste form for the safe immobilization of both high-level defense and high-level commercial radioactive waste. Relative to the borosilicate nuclear waste glasses that are currently the ''reference'' waste form for the long-term disposal of nuclear waste, lead-iron phosphate glasses have several distinct advantages: (1) an aqueous corrosion rate that is about 1000 times lower, (2) a processing temperature that is 100 0 to 250 0 C lower and, (3) a much lower melt viscosity in the temperature range from 800 0 to 1000 0 C. Most significantly, the lead-iron phosphate waste form can be processed using a technology similar to that developed for borosilicate nuclear waste glasses

Nuclear Data Sheets for A = 109

Energy Technology Data Exchange (ETDEWEB)

Kumar, S.; Chen, J.; Kondev, F.G.

2016-11-15

Evaluated nuclear structure and decay data for all nuclei with mass number A = 109 (Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Te, I, Xe) are presented. The experimental data are compiled and evaluated, and the best values for level and gamma-ray energies, quantum numbers, lifetimes, gamma-ray intensities, and other nuclear properties are recommended. Inconsistencies and discrepancies that exist in the literature are noted. This work supersedes the earlier evaluation by J. Blachot (2006Bl02), published in Nuclear Data Sheets107, 355 (2006).

Environmental radioactivity levels, Browns Ferry Nuclear Plant: Annual report, 1986

International Nuclear Information System (INIS)

1986-04-01

The report presents data gathered during radiological monitoring program conducted in the environs of the Browns Ferry Nuclear Plant. Dose estimates were made from concentrations of radioactivity found in samples of media including air, milk, food products, drinking water, and fish. Inhalation and ingestion doses estimated for persons at the indicator locations were essentially identical to those determined for persons at control locations. Greater than 95% of those doses were contributed by the naturally occurring K-40 and by Sr-90 and Cs-137 which are long-lived radioisotopes found in fallout from nuclear weapons testing. Increased levels of I-131 were reported in air, milk, and rainwater following the accident at the Chernobyl nuclear power station. In addition, Ru-103, Cs-137, and Cs-134 were identified in air particulates, and traces of Ru-103 were found in rainwater

Experimental overview and challenge in strangeness nuclear physics — strangeness in the past and coming decades

International Nuclear Information System (INIS)

Imai, Kenichi

2010-01-01

A great progress has been made in strangeness nuclear physics in the past decade. Examples are; 1) The "hyperfine" structure of hypernuclei were measured with the Hyperball, and ΛN spin dependent interactions in p-shell hypernuclei were determined. 2) The "complete measurements" of the weak decay of hypernuclei were made and the np ratio puzzle in the non-mesonic decay was solved. 3) The discovery of a clean event of "Lambpha" and determination of its binding energy concluded that the Λ-Λ interaction is weak attractive. However, we still have important questions to be answered in this field, especially in relation with QCD and nuclear physics. For the future strangeness nuclear physics, we have and will have facilities such as JLab, SPring-8, Daphne, J-PARC, FAIR. We discuss experimental challenges in the strangeness nuclear physics and related fields in the next decade. (author)

Updating and using the international non-neutron experimental nuclear data base in ''Generalized EXFOR'' format

International Nuclear Information System (INIS)

Zhuravleva, G.M.; Chukreev, F.E.

1985-10-01

A software system for the automatic preparation of non-formalized textual information for the international exchange of nuclear data in the ''Generalized Exchange Format (EXFOR)'' is described. The ''Generalized EXFOR'' format is briefly outlined and data are given on the size of the international non-neutron experimental data base in this format. (author)

German Spent Nuclear Fuel Legacy: Characteristics and High-Level Waste Management Issues

Directory of Open Access Journals (Sweden)

A. Schwenk-Ferrero

2013-01-01

Full Text Available Germany is phasing-out the utilization of nuclear energy until 2022. Currently, nine light water reactors of originally nineteen are still connected to the grid. All power plants generate high-level nuclear waste like spent uranium or mixed uranium-plutonium dioxide fuel which has to be properly managed. Moreover, vitrified high-level waste containing minor actinides, fission products, and traces of plutonium reprocessing loses produced by reprocessing facilities has to be disposed of. In the paper, the assessments of German spent fuel legacy (heavy metal content and the nuclide composition of this inventory have been done. The methodology used applies advanced nuclear fuel cycle simulation techniques in order to reproduce the operation of the German nuclear power plants from 1969 till 2022. NFCSim code developed by LANL was adopted for this purpose. It was estimated that ~10,300 tonnes of unreprocessed nuclear spent fuel will be generated until the shut-down of the ultimate German reactor. This inventory will contain ~131 tonnes of plutonium, ~21 tonnes of minor actinides, and 440 tonnes of fission products. Apart from this, ca.215 tonnes of vitrified HLW will be present. As fission products and transuranium elements remain radioactive from 104 to 106 years, the characteristics of spent fuel legacy over this period are estimated, and their impacts on decay storage and final repository are discussed.

Experimental evidence of independence of nuclear de-channeling length on the particle charge sign

Energy Technology Data Exchange (ETDEWEB)

Bagli, E.; Guidi, V.; Mazzolari, A.; Bandiera, L.; Germogli, G.; Sytov, A.I. [Universita di Ferrara, Dipartimento di Fisica e Scienze della Terra (Italy); INFN Sezione di Ferrara (Italy); De Salvador, D. [Universita di Padova, Dipartimento di Fisica e Astronomia, Padua (Italy); INFN Laboratori Nazionali di Legnaro (Italy); Berra, A.; Prest, M. [Universita dell' Insubria, Como (Italy); INFN Sezione di Milano Bicocca, Milan (Italy); Vallazza, E. [INFN Sezione di Trieste (Italy)

2017-02-15

Under coherent interactions, particles undergo correlated collisions with the crystal lattice and their motion result in confinement in the fields of atomic planes, i.e. particle channeling. Other than coherently interacting with the lattice, particles also suffer incoherent interactions with individual nuclei and may leave their bounded motion, i.e., they de-channel. The latter is the main limiting factor for applications of coherent interactions in crystal-assisted particle steering. We experimentally investigated the nature of de-channeling of 120 GeV/c e{sup -} and e{sup +} in a bent silicon crystal at H4-SPS external line at CERN. We found that while channeling efficiency differs significantly for e{sup -} (2 ± 2%) and e{sup +} (54 ± 2%), their nuclear de-channeling length is comparable, (0.6 ± 0.1) mm for e{sup -} and (0.7 ± 0.3) mm for e{sup +}. The experimental proof of the equality of the nuclear de-channeling length for positrons and electrons is interpreted in terms of similar dynamics undergone by the channeled particles in the field of nuclei irrespective of their charge. (orig.)

Symposium on the development of nuclear waste policy: Siting the high-level nuclear waste repository

International Nuclear Information System (INIS)

Pijawka, K.D.; Mushkatel, A.H.

1991-01-01

The Nuclear Waste Policy Act of 1982 (NWPA) attempted to formulate a viable national policy for managing the disposal of high-level nuclear wastes. The NWPA authorized the selection of two repository sites: the first to be constructed in the West and a second site developed in the eastern United States. A detailed process for site selection was outlined in the NWPA. In addition, the NWPA authorized open-quotes the development of a waste transportation system; required the Department of Energy (DOE) to submit a proposal to construct a facility for monitored retrievable storage (MRS) after conducting a study of the need for, and feasibility of such a facility; and required the President to evaluate the use of the repositories ... for the disposal of high-level waste resulting from defense activitiesclose quotes (DOE, 1988, p. 1). A series of provisions granting oversight participation to states and Indian tribes, as well as a compensation package for the ultimate host state were also included. Responsibility for implementing the NWPA was assigned to DOE

European nuclear data studies for fast systems

International Nuclear Information System (INIS)

Rullhusen, P.; Hambsch, F.-J.; Mondelaers, W.; Plompen, A.J.M.; Schillebeeckx, P.

2010-01-01

Nuclear data needs for fast systems are highlighted and the following projects are described: Joint European research projects: MUSE Experiments for Sub-critical Neutronics Validation; High- and Intermediate Energy Nuclear Data for ADS (HINDAS); and the Time-Of-Flight facility for Nuclear Data Measurements for ADS (n T OF N D A DS); European Research Programme for the Transmutation of High Level Nuclear Waste in an Accelerator Driven System (EUROTRANS-NUDATRA); and CANDIDE; Programmes for transnational access to experimental facilities in Europe: European Facilities for Nuclear Data Measurements (EFNUDAT); Neutron Data Measurements at IRMM (NUDAME); European facility for innovative reactor and transmutation neutron data (EUFRAT) (P.A.)

Robotics and remote handling concepts for disposal of high-level nuclear waste

International Nuclear Information System (INIS)

McAffee, Douglas; Raczka, Norman; Schwartztrauber, Keith

1997-01-01

This paper summarizes preliminary remote handling and robotic concepts being developed as part of the US Department of Energy's (DOE) Yucca Mountain Project. The DOE is currently evaluating the Yucca Mountain Nevada site for suitability as a possible underground geologic repository for the disposal of high level nuclear waste. The current advanced conceptual design calls for the disposal of more than 12,000 high level nuclear waste packages within a 225 km underground network of tunnels and emplacement drifts. Many of the waste packages may weigh as much as 66 tonnes and measure 1.8 m in diameter and 5.6 m long. The waste packages will emit significant levels of radiation and heat. Therefore, remote handling is a cornerstone of the repository design and operating concepts. This paper discusses potential applications areas for robotics and remote handling technologies within the subsurface repository. It also summarizes the findings of a preliminary technology survey which reviewed available robotic and remote handling technologies developed within the nuclear, mining, rail and industrial robotics and automation industries, and at national laboratories, universities, and related research institutions and government agencies

An instrumentation and control philosophy for high-level nuclear waste processing facilities

International Nuclear Information System (INIS)

Weigle, D.H.

1990-01-01

The purpose of this paper is to present an instrumentation and control philosophy which may be applied to high-level nuclear waste processing facilities. This philosophy describes the recommended criteria for automatic/manual control, remote/local control, remote/local display, diagnostic instrumentation, interlocks, alarm levels, and redundancy. Due to the hazardous nature of the process constituents of a high-level nuclear waste processing facility, it is imperative that safety and control features required for accident-free operation and maintenance be incorporated. A well-instrumented and controlled process, while initially more expensive in capital and design costs, is generally safer and less expensive to operate. When the long term cost savings of a well designed process is coupled with the high savings enjoyed by accident avoidance, the benefits far outweigh the initial capital and design costs

Plant-Level Modeling and Simulation of Used Nuclear Fuel Dissolution

Energy Technology Data Exchange (ETDEWEB)

de Almeida, Valmor F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2012-09-07

Plant-level modeling and simulation of a used nuclear fuel prototype dissolver is presented. Emphasis is given in developing a modeling and simulation approach to be explored by other processes involved in the recycle of used fuel. The commonality concepts presented in a previous communication were used to create a model and realize its software module. An initial model was established based on a theory of chemical thermomechanical network transport outlined previously. A software module prototype was developed with the required external behavior and internal mathematical structure. Results obtained demonstrate the generality of the design approach and establish an extensible mathematical model with its corresponding software module for a wide range of dissolvers. Scale up numerical tests were made varying the type of used fuel (breeder and light-water reactors) and the capacity of dissolution (0.5 t/d to 1.7 t/d). These tests were motivated by user requirements in the area of nuclear materials safeguards. A computer module written in high-level programing languages (MATLAB and Octave) was developed, tested, and provided as open-source code (MATLAB) for integration into the Separations and Safeguards Performance Model application in development at Sandia National Laboratories. The modeling approach presented here is intended to serve as a template for a rational modeling of all plant-level modules. This will facilitate the practical application of the commonality features underlying the unifying network transport theory proposed recently. In addition, by example, this model describes, explicitly, the needed data from sub-scale models, and logical extensions for future model development. For example, from thermodynamics, an off-line simulation of molecular dynamics could quantify partial molar volumes for the species in the liquid phase; this simulation is currently at reach for high-performance computing. From fluid mechanics, a hold-up capacity function is needed

Experimental and phenomenological comparison between Piezonuclear reactions and Condensed Matter Nuclear Science phenomenology

OpenAIRE

Cardone, F.; Mignani, R.; Petrucci, A.

2011-01-01

The purpose of this paper is to place side by side the experimental results of Piezonu- clear reactions, which have been recently unveiled, and those collected during the last twenty years of experiments on low energy nuclear reactions (LENR). We will briefy re- port the results of our campaign of piezonuclear reactions experiments where ultrasounds and cavitation were applied to solutions of stable elements. These outcomes will be shown to be compatible with the results and evidences obtaine...

Tests of experimental fuel elements by the method of nuclear-thermal pulse loadings in 'HYDRA' reactor

International Nuclear Information System (INIS)

Nastoyashchaya, O.V.; Lebedev, Yu. M.; Chechurov, A.M.; Khvostionov, Ye

1997-01-01

The results of tests of experimental fuel elements with uranium dioxide fuel composition embedded in Al and Zr matrix with the enrichment from 90% to 36% in respect to U-235 performed at the pulse 'HYDRA' reactor are presented in this paper. Testing is performed in the frame-work of extensive research program studying the behavior of fuel elements (FE) of research and mini nuclear power systems in case of practically immediate energy release in the fuel taking place during the RIA-type accidents. Duration of the neutron pulse when testing in 'HYDRA' reactor is from 7 to 20 ms. The methods of diagnostics of the state of FE prior to and after testing in the reactor are developed and verified. Mathematical model describing temperature fields inside the FE in the process of testing. and accounting for non-uniformity of fuel composition has been developed in order to summarize experimental results. Experimental data on the limiting values of the energy density leading to deformation and degradation of FE depending on the type of fuel composition have been obtained and the mechanisms for the development of these processes have been determined. The nature of physical-chemical processes taking place in the fuel composition and fuel cladding depending on material composition under different levels of energy deposition is demonstrated. The data on hydrogen generation and radioactive product release out of fuel after failure of FE are presented. (author)

Training at the masters degree level in physics and technology of nuclear reactors in the uk

International Nuclear Information System (INIS)

Weaver, D.R.

2000-01-01

This paper discusses the current situation of university-based training for the nuclear power industry in the UK, drawing on information gathered as part of the survey for a review currently being undertaken by the Committee for Technical and Economic Studies on Nuclear Energy Development and Fuel Cycle (NDC) of the Nuclear Energy Agency (NEA) of the OECD. A particular focus will be the Physics and Technology of Nuclear Reactors MSc course at the University of Birmingham. In the past there were other similar MSc courses in the UK, but through the evolution of time the Birmingham course is now unique in its role of providing masters level training so specifically aimed at the commercial nuclear programme. Mention will, however, be made of other training at the postgraduate level elsewhere in the UK. A description is given of the need to consider a new form of relationship between industry and university in order to provide optimise the provision of masters level training. (author)

The JAERI-KEK joint project on high intensity proton accelerator and overview of nuclear transmutation experimental facilities

International Nuclear Information System (INIS)

Ikeda, Yujiro

2001-01-01

A status of the JAERI/KEK joint project on High Intensity Proton Accelerator is overviewed. It is highlighted that Experimental facilities for development of the accelerator driven system (ADS) for nuclear transmutation technology is proposed under the project. (author)

Experimental investigation and modelling of tritium washout by precipitation in the area of the nuclear power plant of Paks, Hungary

Energy Technology Data Exchange (ETDEWEB)

Koello, Z., E-mail: kolloz42@gmail.co [Hertelendi Laboratory of Environmental Studies, Institute of Nuclear Research of the Hungarian Academy of Sciences, Bem ter 18/c, Debrecen 4026 (Hungary); Palcsu, L.; Major, Z.; Papp, L.; Molnar, M. [Hertelendi Laboratory of Environmental Studies, Institute of Nuclear Research of the Hungarian Academy of Sciences, Bem ter 18/c, Debrecen 4026 (Hungary); Ranga, T.; Dombovari, P.; Manga, L. [Department of Radiation Protection, Nuclear Power Plant of Paks, Paks (Hungary)

2011-01-15

Tritium occurs in nature in trace amounts, but its concentration is changing due to natural and artificial sources. Studies focusing on natural tritium have to take into account the effect of artificial sources. Also, the impact of tritium is an important issue in environmental protection, e.g. in connection with the emissions from nuclear power plants. The present work focuses on the rain washout of tritium emitted from the Paks nuclear power plant in Hungary. Rainwater collectors were placed around the plant and after a period of precipitation, rainwater was collected and analysed for tritium content. Samples were analysed using low-level liquid scintillation counting, with some also subject to the more accurate {sup 3}He ingrowth method. The results clearly show the trace of the tritium plume emitted from the plant; however, values are only about one order of magnitude higher than environmental background levels. A washout model was devised to estimate the distribution of tritium around the plant. The model gives slightly higher concentrations than those measured in the field, but in general the agreement is satisfactory. The modelled values demonstrate that the effect of the plant on rainwater tritium levels is negligible over a distance of some kilometres. - Research highlights: {yields}The rainwater around a nuclear power plant was collected with a special rainwater collector {yields}The rainwater after a rain event was analysed for tritium with LSC and with the helium ingrowth method. {yields}The trace of the tritium plume is clearly detectable in the rainwater. {yields}The agreement between a reversible washout model and experimental data is satisfactory. {yields}According to the model the tritium plume is hardly detectable over some kilometers from the plant

[Experimental nuclear physics]. Annual report 1989

Energy Technology Data Exchange (ETDEWEB)

NONE

1989-04-01

This is the April 1989 annual report of the Nuclear Physics Labortaory of the University of Washington. It contains chapters on astrophysics, giant resonances, heavy ion induced reactions, fundamental symmetries, polarization in nuclear reactions, medium energy reactions, accelerator mass spectrometry (AMS), research by outside users, Van de Graaff and ion sources, computer systems, instrumentation, and the Laboratory`s booster linac work. An appendix lists Laboratory personnel, Ph.D. degrees granted in the 1988-1989 academic year, and publications. Refs., 23 figs., 3 tabs.

Low energy level density and surface instabilities in heavy transition nuclei

International Nuclear Information System (INIS)

Wieclawik, W. de; Foucher, R.; Dionisio, J.S.; Vieu, C.; Hoglund, A.; Watzig, W.

1975-01-01

A statistical analysis of Au, Pt, Hg nuclear levels was performed with Ericson's method. The odd mass gold experimental number of levels distributions are compared to the theoretical distributions corresponding to vibrational (Alaga and Kisslinger-Sorensen) and rotational (Stephens, Meyer-ter-Vehn) models. The Alaga model gives the most complete description of 193 Au, 195 Au levels and fits the lowest part of Gilbert-Cameron high energy distributions (deduced from the statistical model and neutron capture data). The Ericson's method shows other interesting features of Pt and Hg isotopes (i.e. level density dependence on nuclear shape and pairing correlations, evidence for phase transitions). Consequently, this method is a useful tool for guiding experimental as well as theoretical investigations of transition nuclei [fr

Program for upgrading nuclear materials protection, control, and accounting at all facilities within the All-Russian Institute of Experimental Physics (VNIIEF)

International Nuclear Information System (INIS)

Yuferev, V.; Zhikharev, S.; Yakimov, Y.

1998-01-01

As part of the Department of Energy-Russian program for strengthening nuclear material protection, control, and accounting (MPC and A), plans have now been formulated to install an integrated MPC and A system at all facilities containing large quantities of weapons-usable nuclear material within the All-Russian Institute of Experimental Physics (VNIIEF, Arzamas-16) complex. In addition to storage facilities, the complex houses a number of critical facilities used to conduct nuclear physics research and facilities for developing procedures for disassembly of nuclear weapons

Development, calibration and experimental results obtained with an innovative calorimeter (CALMOS) for nuclear heating measurements

International Nuclear Information System (INIS)

Carcreff, H.; Cloute-Cazalaa, V.; Salmon, L.

2011-01-01

Nuclear heating inside an MTR reactor has to be known in order to be able to control samples temperature during irradiation experiments. An R and D program has been carried out at CEA to design a new type of in-core calorimetric system. This new development, started in 2002, has for main objective to manufacture a calorimeter suitable to monitoring nuclear heating inside the 70 MWth OSIRIS material testing reactor operated by CEA's Nuclear Energy Div. at the Saclay research center. An innovative calorimetric probe, associated to a specific handling system, has been designed to provide access to measurements both along the fissile height and on the upper part of the core, where nuclear heating still remains high. Two mock-ups of the probe were manufactured and tested in 2005 and 2009 in ex-core area of OSIRIS reactor for process validation, while a displacement system has been especially studied to move the probe along a given axial measurement range. This paper deals with the development, tests on preliminary mock-ups and the finalization of the probe. Main modeling and experimental results are presented. Moreover, alternative methods to calibration for nuclear heating rate measurements which are now possible with this new calorimeter are presented and discussed. (authors)

Development, calibration, and experimental results obtained with an innovative calorimeter (CALMOS) for nuclear heating measurements

International Nuclear Information System (INIS)

Carcreff, Hubert; Cloute-Cazalaa, Veronique; Salmon, Laurent

2012-01-01

Nuclear heating inside an MTR reactor has to be known in order to be able to control samples temperature during irradiation experiments. An R and D program has been carried out at CEA to design a new type of in-core calorimetric system. This new development, started in 2002, has for main objective to manufacture a calorimeter suitable to monitoring nuclear heating inside the 70 MWth OSIRIS material testing reactor operated by CEA's Nuclear Energy Division at the Saclay research center. An innovative calorimetric probe, associated to a specific handling system, has been designed to provide access to measurements both along the fissile height and on the upper part of the core, where nuclear heating still remains high. Two mock-ups of the probe were manufactured and tested in 2005 and 2009 in ex-core area of OSIRIS reactor for process validation, while a displacement system has been especially studied to move the probe along a given axial measurement range. This paper deals with the development, tests on preliminary mock-ups and the finalization of the probe. Main modeling and experimental results are presented. Moreover, alternative methods to calibration for nuclear heating rate measurements which are now possible with this new calorimeter are presented and discussed. (authors)

Nuclear Level Densities for Modeling Nuclear Reactions: An Efficient Approach Using Statistical Spectroscopy: Annual Scientific Report July 2004

International Nuclear Information System (INIS)

Calvin W. Johnson

2004-01-01

The general goal of the project is to develop and implement computer codes and input files to compute nuclear densities of state. Such densities are important input into calculations of statistical neutron capture, and are difficult to access experimentally. In particular, we will focus on calculating densities for nuclides in the mass range A ?????? 50 - 100. We use statistical spectroscopy, a moments method based upon a microscopic framework, the interacting shell model. In this report we present our progress for the past year

Experimental Nuclear Physics. Progress report, July 1981-July 1982

International Nuclear Information System (INIS)

1982-01-01

The research activities of the experimental nuclear structure group at Vanderbilt for the period July 1981 to July 1982 are reported. This includes continuing cooperative research in the areas of, (a) in-beam γ-ray spectroscopy with scientists at Oak Ridge and the University of Koeln; (b) studies of nuclei far from stability at UNISOR; (c) pre-equilibrium (massive transfer) emission processes in fusion reactions at ORNL; (d) nucleon transfer reaction studies with scientists at ORNL, Los Alamos and Brookhaven; (e) delta-electron spectroscopy at the Max Planck Institute in Heidelberg; (f) theoretical studies with scientists at Lawrence Berkeley Lab., Brookhaven National Lab., University of Frankfurt, and Vanderbilt; and (g) Coulomb excitation studies at GSI, Darmstadt, Germany. In general, abstracts of papers published or submitted for publication in this period make up this report along with brief reports of work in process and complete copies of a few reviews in press

Experimental aspect of solid-state nuclear magnetic resonance studies of biomaterials such as bones.

Science.gov (United States)

Singh, Chandan; Rai, Ratan Kumar; Sinha, Neeraj

2013-01-01

Solid-state nuclear magnetic resonance (SSNMR) spectroscopy is increasingly becoming a popular technique to probe micro-structural details of biomaterial such as bone with pico-meter resolution. Due to high-resolution structural details probed by SSNMR methods, handling of bone samples and experimental protocol are very crucial aspects of study. We present here first report of the effect of various experimental protocols and handling methods of bone samples on measured SSNMR parameters. Various popular SSNMR experiments were performed on intact cortical bone sample collected from fresh animal, immediately after removal from animal systems, and results were compared with bone samples preserved in different conditions. We find that the best experimental conditions for SSNMR parameters of bones correspond to preservation at -20 °C and in 70% ethanol solution. Various other SSNMR parameters were compared corresponding to different experimental conditions. Our study has helped in finding best experimental protocol for SSNMR studies of bone. This study will be of further help in the application of SSNMR studies on large bone disease related animal model systems for statistically significant results. © 2013 Elsevier Inc. All rights reserved.

Dynamic nuclear polarization at high Landau levels in a quantum point contact

Science.gov (United States)

Fauzi, M. H.; Noorhidayati, A.; Sahdan, M. F.; Sato, K.; Nagase, K.; Hirayama, Y.

2018-05-01

We demonstrate a way to polarize and detect nuclear spin in a gate-defined quantum point contact operating at high Landau levels. Resistively detected nuclear magnetic resonance (RDNMR) can be achieved up to the fifth Landau level and at a magnetic field lower than 1 T. We are able to retain the RDNMR signals in a condition where the spin degeneracy of the first one-dimensional (1D) subband is still preserved. Furthermore, the effects of orbital motion on the first 1D subband can be made smaller than those due to electrostatic confinement. This developed RDNMR technique is a promising means to study electronic states in a quantum point contact near zero magnetic field.

The Hagedorn spectrum, nuclear level densities and first order phase transitions

International Nuclear Information System (INIS)

Moretto, Luciano G.; Larsen, A. C.; Guttormsen, M.; Siem, S.

2015-01-01

An exponential mass spectrum, like the Hagedorn spectrum, with slope 1/T H was interpreted as fixing an upper limiting temperature T H that the system can achieve. However, thermodynamically, such spectrum indicates a 1 st order phase transition at a fixed temperature T H . A much lower energy example is the log linear level nuclear density below the neutron binding energy that prevails throughout the nuclear chart. We show that, for non-magic nuclei, such linearity implies a 1 st order phase transition from the pairing superfluid to an ideal gas of quasi particles

Lead iron phosphate glass as a containment medium for disposal of high-level nuclear waste

Science.gov (United States)

Boatner, Lynn A.; Sales, Brian C.

1989-01-01

Lead-iron phosphate glasses containing a high level of Fe.sub.2 O.sub.3 for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste, a highly corrosion resistant, homogeneous, easily processed glass can be formed. For corroding solutions at 90.degree. C., with solution pH values in the range between 5 and 9, the corrosion rate of the lead-iron phosphate nuclear waste glass is at least 10.sup.2 to 10.sup.3 times lower than the corrosion rate of a comparable borosilicate nuclear waste glass. The presence of Fe.sub.2 O.sub.3 in forming the lead-iron phosphate glass is critical. Lead-iron phosphate nuclear waste glass can be prepared at temperatures as low as 800.degree. C., since they exhibit very low melt viscosities in the 800.degree. to 1050.degree. C. temperature range. These waste-loaded glasses do not readily devitrify at temperatures as high as 550.degree. C. and are not adversely affected by large doses of gamma radiation in H.sub.2 O at 135.degree. C. The lead-iron phosphate waste glasses can be prepared with minimal modification of the technology developed for processing borosilicate glass nuclear wasteforms.

Ceramic process and plant design for high-level nuclear waste immobilization

International Nuclear Information System (INIS)

Grantham, L.F.; McKisson, R.L.; De Wames, R.E.; Guon, J.; Flintoff, J.F.; McKenzie, D.E.

1983-01-01

In the last 3 years, significant advances in ceramic technology for high-level nuclear waste solidification have been made. Product quality in terms of leach-resistance, compositional uniformity, structural integrity, and thermal stability promises to be superior to borosilicate glass. This paper addresses the process effectiveness and preliminary designs for glass and ceramic immobilization plants. The reference two-step ceramic process utilizes fluid-bed calcination (FBC) and hot isostatic press (HIP) consolidation. Full-scale demonstration of these well-developed processing steps has been established at DOE and/or commercial facilities for processing radioactive materials. Based on Savannah River-type waste, our model predicts that the capital and operating cost for the solidification of high-level nuclear waste is about the same for the ceramic and glass options. However, when repository costs are included, the ceramic option potentially offers significantly better economics due to its high waste loading and volume reduction. Volume reduction impacts several figures of merit in addition to cost such as system logistics, storage, transportation, and risk. The study concludes that the ceramic product/process has many potential advantages, and rapid deployment of the technology could be realized due to full-scale demonstrations of FBC and HIP technology in radioactive environments. Based on our finding and those of others, the ceramic innovation not only offers a viable backup to the glass reference process but promises to be a viable future option for new high-level nuclear waste management opportunities

Regulatory oversight report 2016 concerning nuclear safety in Swiss nuclear installations

International Nuclear Information System (INIS)

2017-06-01

packages as well as one cask with the fuel assemblies from the shut down research reactor DIORIT of PSI and six casks with waste from the decommissioning of the experimental nuclear power plant at Lucens. During 2016 only one campaign to incinerate and melt radioactive waste was carried out. ENSI recorded no reportable events at Zwilag during the reporting year. The nuclear facilities at PSI consist of the hot laboratory, the three former research reactors SAPHIR, DIORIT and PROTEUS now in varying phases of decommissioning, the former experimental incineration plant and the facilities for the disposal of radioactive materials including the Federal Government's interim storage facility. During 2016, no events were reported at the PSI, at EPFL or at UniB. In 2016, the amount of radioactive material released into the environment via waste water and exhaust air from the nuclear power plants, Zwilag and the nuclear facilities at PSI, Basel and Lausanne was significantly less than the limits specified in the operating licenses. Analyses showed that the maximum dose for persons in the immediate vicinity of a plant was less than 1% of the annual exposure to natural radiation. The waste produced during reprocessing at the reprocessing facilities of La Hague (France) and Sellafield (United Kingdom) must be returned to Switzerland. In the reporting year, compacted, metallic, intermediate level waste and intermediate level vitrified residue packets were transported to Zwilag. All nuclear waste from Swiss fuel assemblies sent abroad for reprocessing is now stored at Zwilag. During 2016, all transports of radioactive substances to and from Swiss nuclear installations took place without any incidents. The site selection procedure for the storage of radioactive waste has been running since 2008. ENSI bears overall responsibility for the safety assessment of the geological site areas. The National Cooperative for the Disposal of Radioactive Waste (Nagra) submitted its suggestion for

Initial performance assessment of the disposal of spent nuclear fuel and high-level waste stored at Idaho National Engineering Laboratory

International Nuclear Information System (INIS)

Rechard, R.P.

1993-12-01

This performance assessment characterized plausible treatment options conceived by the Idaho National Engineering Laboratory (INEL) for its spent fuel and high-level radioactive waste and then modeled the performance of the resulting waste forms in two hypothetical, deep, geologic repositories: one in bedded salt and the other in granite. The results of the performance assessment are intended to help guide INEL in its study of how to prepare wastes and spent fuel for eventual permanent disposal. This assessment was part of the Waste Management Technology Development Program designed to help the US Department of Energy develop and demonstrate the capability to dispose of its nuclear waste, as mandated by the Nuclear Waste Policy Act of 1982. The waste forms comprised about 700 metric tons of initial heavy metal (or equivalent units) stored at the INEL: graphite spent fuel, experimental low enriched and highly enriched spent fuel, and high-level waste generated during reprocessing of some spent fuel. Five different waste treatment options were studied; in the analysis, the options and resulting waste forms were analyzed separately and in combination as five waste disposal groups. When the waste forms were studied in combination, the repository was assumed to also contain vitrified high-level waste from three DOE sites for a common basis of comparison and to simulate the impact of the INEL waste forms on a moderate-sized repository, The performance of the waste form was assessed within the context of a whole disposal system, using the U.S. Environmental Protection Agency's Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes, 40 CFR 191, promulgated in 1985. Though the waste form behavior depended upon the repository type, all current and proposed waste forms provided acceptable behavior in the salt and granite repositories

Experimental study on accelerator driven subcritical reactor. JAERI's nuclear research promotion program, H12-031 (Contract research)

International Nuclear Information System (INIS)

Shiroya, Seiji; Misawa, Tsuyoshi; Unesaki, Hironobu

2004-03-01

In view of the future plan of Research Reactor Institute, Kyoto University (KURRI), the present study consisted of 1) the transmission experiments of high energy neutrons through materials, 2) experimental simulation of ADSR using the Kyoto University Critical Assembly (KUCA), and 3) conceptual neutronics design study on Kyoto University Reactor (KUR) type ADSR using the MCNPX code. The purpose of the present study was not only to obtain the knowledge usable for the realization of ADSR as a new neutron source for research but also to select technical issues in the field of reactor physics for the development of ADSR in general. Through the present study, valuable knowledge on the basic nuclear characteristics of ADSR was obtained both theoretically and experimentally. This kind of knowledge is indispensable to promote the study on ADSR further. If one dare say the main part of knowledge in short words, the basic nuclear characteristics of ADSR is overwhelmed by the characteristics of the subcritical reactor as expected. For the realization of ADSR in the future, it is considered to be necessary to accumulate results of research steadily. For this purpose, it is inevitable 1) to compile the more precise nuclear data for the wide energy range, 2) to establish experimental techniques for reactor physics study on ADSR including subcriticality measurement and absolute neutron flux measurement from the low energy region to the high energy region, and 3) to develop neutronics calculation tools which facilitate to take into account the neutron generation process by the spallation reaction and the delayed neutron behavior. (author)

The management-retrieval code of nuclear level density sub-library (CENPL-NLD)

International Nuclear Information System (INIS)

Ge Zhigang; Su Zongdi; Huang Zhongfu; Dong Liaoyuan

1995-01-01

The management-retrieval code of the Nuclear Level Density (NLD) is presented. It contains two retrieval ways: single nucleus (SN) and neutron reaction (NR). The latter contains four kinds of retrieval types. This code not only can retrieve level density parameter and the data related to the level density, but also can calculate the relevant data by using different level density parameters and do comparison of the calculated results with related data in order to help user to select level density parameters

Stochastic estimation of nuclear level density in the nuclear shell model: An application to parity-dependent level density in 58Ni

Directory of Open Access Journals (Sweden)

Noritaka Shimizu

2016-02-01

Full Text Available We introduce a novel method to obtain level densities in large-scale shell-model calculations. Our method is a stochastic estimation of eigenvalue count based on a shifted Krylov-subspace method, which enables us to obtain level densities of huge Hamiltonian matrices. This framework leads to a successful description of both low-lying spectroscopy and the experimentally observed equilibration of Jπ=2+ and 2− states in 58Ni in a unified manner.

Second Mexican School of Nuclear Physics: Notes; Segunda Escuela Mexicana de Fisica Nuclear: Notas

Energy Technology Data Exchange (ETDEWEB)

Aguilera, E F [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Chavez L, E R [Instituto de Fisica, UNAM, 04510 Mexico D.F. (Mexico); Hess, P O [Instituto de Ciencias Nucleares, UNAM, 04510 Mexico D.F. (Mexico)

2001-07-01

The II Mexican School of Nuclear Physics which is directed to those last semesters students of the Physics career or post-graduate was organized by the Nuclear Physics Division of the Mexican Physics Society, carrying out at April 16-27, 2001 in the installations of the Institute of Physics and the Institute of Nuclear Sciences, both in the UNAM, and the National Institute of Nuclear Research (ININ). A first school of a similar level in Nuclear Physics, was carried out in Mexico at 1977 as Latin american School of Physics. This book treats about the following themes: Interactions of radiation with matter, Evaluation of uncertainty in experimental data, Particle accelerators, Notions of radiological protection and dosimetry, Cosmic rays, Basis radiation (environmental), Measurement of excitation functions with thick targets and inverse kinematics, Gamma ray technique for to measure the nuclear fusion, Neutron detection with Bonner spectrometer, Energy losses of alpha particles in nickel. It was held the practice Radiation detectors. (Author)

An experimental study of assessment of weld quality on fatigue reliability analysis of a nuclear pressure vessel

International Nuclear Information System (INIS)

Dai Shuhe

1993-01-01

The steam generator in PWR primary coolant system China of Qinshan Nuclear Power Plant is a crucial unit belonging to the category of nuclear pressure vessel. The purpose of this research work is to make an examination of the weld quality of the steam generator under fatigue loading and to assess its reliability by using the experimental results of fatigue test of material of nuclear pressure vessel S-271 (Chinese Standard) and of qualified tests of welded seams of a simulated prototype of bottom closure head of the steam generator. A guarantee of weld quality is proposed as a subsequent verification for China National Nuclear Safety Supervision Bureau. The results of reliability analysis reported in this work can be taken as a supplementary material of Probabilistic Safety Assessment (PSA) of Qinshan Nuclear Power Plant. According to the requirement of Provision II-1500 cyclic testing, ASME Boiler and Pressure Vessel Code, Section III, Rules for Construction of Nuclear Power Plant Components, a simulated prototype of the bottom closure head of the steam generator was made for qualified tests. To find the quantified results of reliability assessment by using the testing data, two proposals are presented

Experimental study of the natural circulation phenomena

International Nuclear Information System (INIS)

Sabundjian, Gaiane; Andrade, Delvonei Alves de; Umbehaun, Pedro E.; Torres, Walmir M.; Castro, Alfredo Jose Alvim de; Belchior Junior, Antonio; Rocha, Ricardo Takeshi Vieira da; Damy, Osvaldo Luiz de Almeida; Torres, Eduardo

2006-01-01

The objective of this paper is to study the natural circulation in experimental loops and extend the results to nuclear facilities. New generation of compact nuclear power plants use the natural circulation as cooling and residual heat removal systems in case of accidents or shutdown. Lately the interest in this phenomenon, by scientific community, has increased. The experimental loop, described in this paper, was assembled at Escola Politecnica - USP at the Chemical Engineering Department. It is the goal to generate information to help with the understanding of the one and two phase natural circulation phenomena. Some experiments were performed with different levels of heat power and different flow of the cooling water at the secondary circuit. The data generated from these experiments are going to be used to validate some computational thermal hydraulic codes. Experimental results for one and two phase regimes are presented as well as the proposed model to simulate the flow regimes with the RELAP5 code. (author)

Estimation of radioactive contamination of soils from the "Balapan" and the "Experimental field" technical areas of the Semipalatinsk nuclear test site.

Science.gov (United States)

Evseeva, T; Belykh, E; Geras'kin, S; Majstrenko, T

2012-07-01

In spite of the long history of the research, radioactive contamination of the Semipalatinsk nuclear test site (SNTS) in the Republic of Kazakhstan has not been adequately characterized. Our cartographic investigation has demonstrated highly variable radioactive contamination of the SNTS. The Cs-137, Sr-90, Eu-152, Eu-154, Co-60, and Am-241 activity concentrations in soil samples from the "Balapan" site were 42.6-17646, 96-18250, 1.05-11222, 0.6-4865, 0.23-4893, and 1.2-1037 Bq kg(-1), correspondingly. Cs-137 and Sr-90 activity concentrations in soil samples from the "Experimental field" site were varied from 87 up to 400 and from 94 up to 1000 Bq kg(-1), respectively. Activity concentrations of Co-60, Eu-152, and Eu-154 were lower than the minimum detectable activity of the method used. Concentrations of naturally occurring radionuclides (K-40, Ra-226, U-238, and Th-232) in the majority of soil samples from the "Balapan" and the "Experimental field" sites did not exceed typical for surrounding of the SNTS areas levels. Estimation of risks associated with radioactive contamination based on the IAEA clearance levels for a number of key radionuclides in solid materials shows that soils sampled from the "Balapan" and the "Experimental field" sites might be considered as radioactive wastes. Decrease in specific activity of soil from the sites studied up to safety levels due to Co-60, Cs-137, Sr-90, Eu-152, Eu-154 radioactive decay and Am-241 accumulation-decay will occur not earlier than 100 years. In contrast, soils from the "Experimental field" and the "Balapan" sites (except 0.5-2.5 km distance from the "Chagan" explosion point) cannot be regarded as the radioactive wastes according safety norms valid in Russia and Kazakhstan. Copyright © 2012 Elsevier Ltd. All rights reserved.

Development of national level preparedness for response to nuclear and radiological emergencies

International Nuclear Information System (INIS)

Pradeepkumar, K.S.

2014-01-01

In India, DAE being the nodal agency for technical support for response to any radiation emergency nuclear disaster and various nuclear and radiological emergency scenarios and their impacts are identified. To reduce their consequences development of methodologies for detection and quick impact assessment, trained First Responders and Quick Response Teams (QRTs), twenty two DAE Emergency Response Centers, mobile and aerial radiation monitoring systems, aerial and ground based validation trials etc. are carried out. Study related to radiological threats and simulated RDD experiments conducted using stable isotopes indicates that radiation levels for distances more than 50 m will not be very high as hotspots may be restricted to nearby area. The biggest challenge from an RDD explosion will be handling of the radioactive contamination and 'fear factor' compared to radiation exposure to public or First Responders. Level and pattern of radioactive contamination on ground following releases during nuclear accidents and minimum strength of orphan radioactive sources to be detected are taken into account for optimizing systems and monitoring methodology required for emergency preparedness

Nuclear Accidents Intervention Levels for Protection of the Public

International Nuclear Information System (INIS)

1989-01-01

The impact of the 1986 Chernobyl accident called attention to the need to improve international harmonization of the principles and criteria for the protection of the public in the event of a nuclear accident. This report provides observations and guidance related to the harmonization of radiological protection criteria, and is intended to be of use to national authorities and international organizations examining the issue of emergency response planning and intervention levels

Experimental analysis of a nuclear reactor prestressed concrete pressure vessels model

International Nuclear Information System (INIS)

Vallin, C.

1980-01-01

A comprehensible analysis was made of the performance of each set of sensors used to measure the strain and displacement of a 1/20 scale Prestressed Concrete Pressure Vessel (PCPV) model tested at the Instituto de Pesquisas Energeticas e Nucleares (IPEN). Among the three Kinds of sensors used (strain gage, displacement transducers and load cells) the displacement transducers showed the best behavior. The displacemente transducers data was statistically analysed and a linear behavior of the model was observed during the first pressurizations tests. By means of a linear statistical correlation between experimental and expected theoretical data it was found that the model looses the linearity at a pressure between 110-125 atm. (Author) [pt

Architectural-level power estimation and experimentation

Science.gov (United States)

Ye, Wu

With the emergence of a plethora of embedded and portable applications and ever increasing integration levels, power dissipation of integrated circuits has moved to the forefront as a design constraint. Recent years have also seen a significant trend towards designs starting at the architectural (or RT) level. Those demand accurate yet fast RT level power estimation methodologies and tools. This thesis addresses issues and experiments associate with architectural level power estimation. An execution driven, cycle-accurate RT level power simulator, SimplePower, was developed using transition-sensitive energy models. It is based on the architecture of a five-stage pipelined RISC datapath for both 0.35mum and 0.8mum technology and can execute the integer subset of the instruction set of SimpleScalar . SimplePower measures the energy consumed in the datapath, memory and on-chip buses. During the development of SimplePower , a partitioning power modeling technique was proposed to model the energy consumed in complex functional units. The accuracy of this technique was validated with HSPICE simulation results for a register file and a shifter. A novel, selectively gated pipeline register optimization technique was proposed to reduce the datapath energy consumption. It uses the decoded control signals to selectively gate the data fields of the pipeline registers. Simulation results show that this technique can reduce the datapath energy consumption by 18--36% for a set of benchmarks. A low-level back-end compiler optimization, register relabeling, was applied to reduce the on-chip instruction cache data bus switch activities. Its impact was evaluated by SimplePower. Results show that it can reduce the energy consumed in the instruction data buses by 3.55--16.90%. A quantitative evaluation was conducted for the impact of six state-of-art high-level compilation techniques on both datapath and memory energy consumption. The experimental results provide a valuable insight for

Field studies to determine acceptable levels of contamination at former UK nuclear testing sites, Maralinga and Emu in Australia

International Nuclear Information System (INIS)

Davy, D.R.

1988-01-01

The Maralinga and Emu regions of South Australia were used between 1953 and 1961 for the UK nuclear weapon development program. Two types of trials were conducted - the major trials involved the detonation of fission weapons and the minor trials dealt with weapon design and operational safety. In 1986, as a result of the findings of the Royal Commission on Nuclear Testing in Australia, the UK and Australian governments agreed to set up a Technical Assessment Group (TAG) with one American, two Australian and two British members to review the Maralinga-Emu situation. TAG was to advise on a series of clean-up options and their associated costs and examine land-use options ranging from unrestricted use by the traditional Aboriginal land owners to options involving various degrees of administrative and physical control. In its interim report, presented in May 1986, TAG observed that the existing data base was inadequate and suggested a series of field and laboratory studies that would partly correct this situation. Six of these studies were concerned with redefining the existing levels of contamination and establishing acceptable levels of contamination for a range of land-use options. This paper discusses the rationale, organisational support, scope and experimental protocol adopted for each of the six studies

Optimization of preventive maintenance cycle based on experimental feedback in nuclear power plants

International Nuclear Information System (INIS)

Shi Jie

2010-01-01

The preventive replacement method based on the experimental feedback was introduced. In this method, the initial preventive replacement cycle was acquired by expert votes. The preventive replacement cycle combined with the operation experience of the equipment was gained by means of Bayesian theorem. The Optimized preventive replacement cycle can be acquired by comparing the two probabilities that no fault occurs within the cycle. This method was tested on the switches which were used in Daya Bay Nuclear Power Plant and the results indicated its validity. (authors)

Level-one modules library for DSNP: Dynamic Simulator for Nuclear Power-plants

International Nuclear Information System (INIS)

Saphier, D.

1978-09-01

The Dynamic Simulator for Nuclear Power-plants (DSNP) is a system of programs and data sets by which a nuclear power plant or part thereof can be simulated at different levels of sophistication. The acronym DSNP is used interchangeably for the DSNP language, for the DSNP precompiler, for the DSNP libraries, and for the DSNP document generator. The DSNP language is a set of simple block oriented statements, which together with the appropriate data, comprise a simulation of a nuclear power plant. The majority of the DSNP statements will result in the inclusion of a simulated physical module into the program. FORTRAN statements can be inserted with no restrictions among DSNP statements

Feasibility study of the AOSTA experimental campaign

Directory of Open Access Journals (Sweden)

Carta M.

2016-01-01

Full Text Available The reduction of the nuclear waste is one of the most important nuclear issues. The high radiotoxicity of the spent fuel is due to plutonium and some minor actinides (MAs such as neptunium, americium and curium, above all. One way to reduce their hazard is to destroy by fission MAs in appropriate nuclear reactors. To allow the MAs destruction an important effort have been done on the nuclear data due to the poor knowledge in this field. In the framework of one of the NEA Expert Group on Integral Experiments for Minor Actinide Management an analysis of the feasibility of MAs irradiation campaign in the TAPIRO fast research reactor is carried out. This paper provides preliminary results obtained by calculations modelling the irradiation, in different TAPIRO irradiation channels, of some CEA samples coming from the French experimental campaign OSMOSE, loaded with different contents of MAs, in order to access, through particular peak spectrometry, to their capture cross section. On the basis of neutron transport calculation results, obtained by both deterministic and Monte Carlo methods, an estimate of the irradiated samples counting levels from the AOSTA (Activation of OSMOSE Samples in TAPIRO experimental campaign is provided.

Higher serum levels of rheumatoid factor and anti-nuclear antibodies in helicobacter pylori-infected peptic ulcer patients.

Science.gov (United States)

Jafarzadeh, Abdollah; Nemati, Maryam; Rezayati, Mohammad Taghi; Nabizadeh, Mansooreh; Ebrahimi, Medhi

2013-07-01

H. pylori infection has been associated with some autoimmune disorders. The aim of this study was to evaluate the serum concentrations of rheumatoid factor and anti-nuclear antibodies in H. pylori-infected peptic ulcer patients, H. pylori-infected asymptomatic carriers and a healthy control group. A Total of 100 H. pylori-infected peptic ulcer patients, 65 asymptomatic carriers and 30 healthy H. pylori-negative subjects (as a control group) were enrolled into study. Serum samples of participants tested for the levels of rheumatoid factor and anti-nuclear antibodies by use of ELISA. The mean serum levels of rheumatoid factor and anti-nuclear antibodies in peptic ulcer group was significantly higher in comparison to the control group (ppeptic ulcer patients and asymptomatic carriers groups regarding the mean serum levels of rheumatoid factor and anti-nuclear antibodies. The mean serum levels of rheumatoid factor in men with peptic ulcer was significantly higher compared to the group of healthy men (ppeptic ulcer patients or asymptomatic carriers groups, the mean serum levels of rheumatoid factor was higher than that in healthy women, but the differences were not statistically significant. Also, no significant differences were observed between men and women with peptic ulcer, asymptomatic carriers control groups based on the serum levels of anti-nuclear antibodies. The results showed higher serum levels of rheumatoid factor and anti-nuclear antibodies in H. pylori-infected patients with peptic ulcer disease which represent the H. pylori-related immune disturbance in these patients. Additional follow-up studies are necessary to clarify the clinical significance of these autoantibodies in patients with H. pylori infection.

Float level switch for a nuclear power plant containment vessel

International Nuclear Information System (INIS)

Powell, J.G.

1993-01-01

This invention is a float level switch used to sense rise or drop in water level in a containment vessel of a nuclear power plant during a loss of coolant accident. The essential components of the device are a guide tube, a reed switch inside the guide tube, a float containing a magnetic portion that activates a reed switch, and metal-sheathed, ceramic-insulated conductors connecting the reed switch to a monitoring system outside the containment vessel. Special materials and special sealing techniques prevent failure of components and allow the float level switch to be connected to a monitoring system outside the containment vessel. 1 figures

Float level switch for a nuclear power plant containment vessel

Science.gov (United States)

Powell, James G.

1993-01-01

This invention is a float level switch used to sense rise or drop in water level in a containment vessel of a nuclear power plant during a loss of coolant accident. The essential components of the device are a guide tube, a reed switch inside the guide tube, a float containing a magnetic portion that activates a reed switch, and metal-sheathed, ceramic-insulated conductors connecting the reed switch to a monitoring system outside the containment vessel. Special materials and special sealing techniques prevent failure of components and allow the float level switch to be connected to a monitoring system outside the containment vessel.

The Hagedorn spectrum, nuclear level densities and first order phase transitions

Energy Technology Data Exchange (ETDEWEB)

Moretto, Luciano G., E-mail: lgmoretto@lbl.gov [Department of Chemistry, University of California, Berkeley, Lawrence Berkeley National Laboratory 1 Cyclotron Road, Berkeley, CA 94720 (United States); Larsen, A. C.; Guttormsen, M.; Siem, S. [Department of Physics, University of Oslo, N-0316 Oslo (Norway)

2015-10-15

An exponential mass spectrum, like the Hagedorn spectrum, with slope 1/T{sub H} was interpreted as fixing an upper limiting temperature T{sub H} that the system can achieve. However, thermodynamically, such spectrum indicates a 1{sup st} order phase transition at a fixed temperature T{sub H}. A much lower energy example is the log linear level nuclear density below the neutron binding energy that prevails throughout the nuclear chart. We show that, for non-magic nuclei, such linearity implies a 1{sup st} order phase transition from the pairing superfluid to an ideal gas of quasi particles.

Attempted development and cross-validation of predictive models of individual-level and organizational-level turnover of nuclear power operators

International Nuclear Information System (INIS)

Vasa-Sideris, S.J.

1989-01-01

Nuclear power accounts for 209% of the electric power generated in the U.S. by 107 nuclear plants which employ over 8,700 operators. Operator turnover is significant to utilities from the economic point of view since it costs almost three hundred thousand dollars to train and qualify one operator, and because turnover affects plant operability and therefore plant safety. The study purpose was to develop and cross-validate individual-level and organizational-level models of turnover of nuclear power plant operators. Data were obtained by questionnaires and from published data for 1983 and 1984 on a number of individual, organizational, and environmental predictors. Plants had been in operation for two or more years. Questionnaires were returned by 29 out of 50 plants on over 1600 operators. The objectives were to examine the reliability of the turnover criterion, to determine the classification accuracy of the multivariate predictive models and of categories of predictors (individual, organizational, and environmental) and to determine if a homology existed between the individual-level and organizational-level models. The method was to examine the shrinkage that occurred between foldback design (in which the predictive models were reapplied to the data used to develop them) and cross-validation. Results did not support the hypothesis objectives. Turnover data were accurate but not stable between the two years. No significant differences were detected between the low and high turnover groups at the organization or individual level in cross-validation. Lack of stability in the criterion, restriction of range, and small sample size at the organizational level were serious limitations of this study. The results did support the methods. Considerable shrinkage occurred between foldback and cross-validation of the models

Mechanical properties of buffer materials for repositories of high-level nuclear waste, 2

International Nuclear Information System (INIS)

Komine, Hideo; Ogata, Nobuhide

1993-01-01

Compacted bentonites have attracted increasing attention as back filling (buffer) materials for repositories of high-level nuclear waste. However, since little has been known concerning the swelling characteristics of compacted bentonites, it is necessary to clarify the fundamental swelling characteristics and the quantitative evaluation on this characteristics is required. For this purpose, a theoretical model concerning the swelling characteristics (swelling deformation and swelling pressure) of compacted bentonites were developed. The following conclusions were drawn from this theoretical study; (1) The evaluation formula of the swelling characteristics of compacted bentonites based on the diffuse double layer theory has been proposed by combining the theoretical model and the theoretical equation to estimate the swelling characteristics of a crystal. (2) The applicability of the evaluation formula proposed in this study has been confirmed by the comparison of the experimental results with calculated results. The sensitivity of this evaluation formula has also been investigated to find that the swelling characteristics is strongly dependent on the ion concentration of pore water and on the montmorillonite content of bentonite. (author)

CFD analysis and experimental investigation associated with the design of the Los Alamos nuclear materials storage facility

International Nuclear Information System (INIS)

Bernardin, J.D.; Hopkins, S.; Gregory, W.S.; Martin, R.A.

1997-01-01

The Nuclear Materials Storage Facility (NMSF) at the Los Alamos National Laboratory is being renovated for long-term storage of canisters designed to hold heat-generating nuclear materials, such as powders, ingots, and other components. The continual heat generation within the canisters necessitates a reliable cooling scheme of sufficient magnitude which maintains the stored material temperatures within acceptable limits. The primary goal of this study was to develop both an experimental facility and a computational fluid dynamics (CFD) model of a subsection of the NMSF which could be used to observe general performance trends of a proposed passive cooling scheme and serve as a design tool for canister holding fixtures. Comparisons of numerical temperature and velocity predictions with empirical data indicate that the CFD model provides an accurate representation of the NMSF experimental facility. Minor modifications in the model geometry and boundary conditions are needed to enhance its accuracy, however, the various fluid and thermal models correctly capture the basic physics

On the study of level density parameters for some deformed light nuclei

International Nuclear Information System (INIS)

Sonmezoglu, S.

2005-01-01

The nuclear level density, which is the number of energy levels/MeV at an excitation energy Ex , is a characteristic property of every nucleus. Total level densities are among the key quantities in statistical calculations in many fields, such as nuclear physics, astrophysics, spallation s neutrons measurements, and studies of intermediate-energy heavy-ion collisions. The nuclear level density is an important physical quantity both from the fundamental point of view as well as in understanding the particle and gamma ray emission in various reactions. In light and heavy deformed nucleus, the gamma-ray energies drop with decreasing spin in a very regular fashion. The nuclear level density parameters have been usually used in investigation of the nuclear level density. This parameter itself changes with excitation energy depending on both shell effect in the single particle model and different excitation modes in the collective models. In this study, the energy level density parameters of some deformed light nucleus (40 C a, 47 T i, 59 N i, 79 S e, 80 B r) are determined by using energy spectrum of the interest nucleus for different band. In calculation of energy-level density parameters dependent upon excitation energy of nuclei studied, a model was considered which relies on the fact that energy levels of deformed light nuclei, just like those of deformed heavy nuclei, are equidistant and which relies on collective motions of their nucleons. The present calculation results have been compared with the corresponding experimental and theoretical results. The obtained results are in good agreement with the experimental results

Results of the power-up test of the nuclear-powered ship MUTSU and test programs of her experimental voyages

International Nuclear Information System (INIS)

Ochiai, Masa-aki; Ishida, Toshihisa; Itagaki, Masafumi; Sakamoto, Yukio; Kyouya, Masahiko

1991-01-01

The power-up test of N.S. MUTSU was performed successfully almost on schedule in spite of minor troubles resolved in a short time, and the results of various areas were satisfactory. The official sea trial was well carried out. Then, the ship was officially designated the first nuclear ship in Japan. Experimental voyages are to be performed to yield profitable data for further research on nuclear ships in the future. (author)

Molecular-nuclear transitions

International Nuclear Information System (INIS)

Belyaev, V.B.; Miller, M.B.

2007-01-01

Full text: The spectra in some light nuclei have one interesting property. For example, in the closed vicinity of some resonance states of such nuclei as 5 He, 8 Be, 18 F, 18 Ne the thresholds exist for two- or three-body decay of those nuclei. Let us consider the lightest of the above nuclei, 5 He. The energy threshold for 5 He > d+t decay is ∼50 keV lower than the energy of 3/2 + state of 5 He nucleus. However, due to a rather large width of this state, ∼70 keV, the nuclear capture of deuterons by tritons in dtm-molecule is highly enhanced in comparison with the process of dd capture in the ddm molecule. The physical reason for the enhancement of the probability of the capture into the resonant state can be associated with a long tail of wave function of the resonant state and, accordingly, with the large value of the overlap integral determining in general the probability of the transition between two systems. Thus, one can expect the enhancement of the molecular-nuclear transitions, and this was indeed observed experimentally for the case of dtm molecule. Now, let us consider some other molecular-nuclear combinations: 18 Ne - H 2 O, 18 F - 17 OH, and 8 Be - 6 LiD molecule. With the high accuracy the energies of the above molecular systems coincide with the energies of the resonant states in the appropriate nuclei. Due to the uncertainty in the experimental nuclear data it is not known at present whether the energies of these thresholds are lower or higher of the corresponding energies of the nuclear resonances. Let us assume that the molecular energy is few keV over the energy of the nuclear resonance. Then, we will deal with a very interesting phenomenon: the molecular-nuclear complex constitutes a two level system, which in some sense is analogous to the two-level atomic system, as in a laser. The crucial difference between this one and the two-level atomic systems consists in a fact that in the molecular-nuclear case no special procedure of pumping up

The scope and nature of the problem of high level nuclear waste disposal

International Nuclear Information System (INIS)

Jennekens, J.

1981-09-01

The disposal of high level nuclear waste poses a challenge to the Canadian technical and scientific communities, but a much greater challenge to government and industry leaders who must convince the public that the so-called 'problem' can be resolved by a pragmatic approach utilizing existing skills and knowledge. This paper outlines the objectives of radioactive waste management, the quantities of high level waste expected to be produced by the Canadian nuclear power program, the regulatory process which will apply and the government initiatives which have been and will be taken to ensure that the health, safety, security, and environmental interests of the public will be protected. (author)

Extension of the energy range of experimental activation cross-sections data of deuteron induced nuclear reactions on indium up to 50MeV.

Science.gov (United States)

Tárkányi, F; Ditrói, F; Takács, S; Hermanne, A; Ignatyuk, A V

2015-11-01

The energy range of our earlier measured activation cross-sections data of longer-lived products of deuteron induced nuclear reactions on indium were extended from 40MeV up to 50MeV. The traditional stacked foil irradiation technique and non-destructive gamma spectrometry were used. No experimental data were found in literature for this higher energy range. Experimental cross-sections for the formation of the radionuclides (113,110)Sn, (116m,115m,114m,113m,111,110g,109)In and (115)Cd are reported in the 37-50MeV energy range, for production of (110)Sn and (110g,109)In these are the first measurements ever. The experimental data were compared with the results of cross section calculations of the ALICE and EMPIRE nuclear model codes and of the TALYS 1.6 nuclear model code as listed in the on-line library TENDL-2014. Copyright © 2015 Elsevier Ltd. All rights reserved.

Atmospheric Dispersion Simulation for Level 3 PSA at Ulchin Nuclear Site using a PUFF model

Energy Technology Data Exchange (ETDEWEB)

Lee, Seung Jun; Han, Seok-Jung; Jeong, Hyojoon; Jang, Seung-Cheol [KAERI, Daejeon (Korea, Republic of)

2015-05-15

Air dispersion prediction is a key in the level 3 PSA to predict radiation releases into the environment for preparing an effective strategy for an evacuation as a basis of the emergency preparedness. To predict the atmospheric dispersion accurately, the specific conditions of the radiation release location should be considered. There are various level 3 PSA tools and MACSS2 is one of the widely used level 3 PSA tools in many countries including Korea. Due to the characteristics of environmental conditions in Korea, it should be demonstrated that environmental conditions of Korea nuclear sites can be appropriately illustrated by the tool. In Korea, because all nuclear power plants are located on coasts, sea and land breezes might be a significant factor. The objectives of this work is to simulate the atmospheric dispersion for Ulchin nuclear site in Korea using a PUFF model and to generate the data which can be used for the comparison with that of PLUME model. A nuclear site has own atmospheric dispersion characteristics. Especially in Korea, nuclear sites are located at coasts and it is expected that see and land breeze effects are relatively high. In this work, the atmospheric dispersion at Ulchin nuclear site was simulated to evaluate the effect of see and land breezes in four seasons. In the simulation results, it was observed that the wind direction change with time has a large effect on atmospheric dispersion. If the result of a PLUME model is more conservative than most severe case of a PUFF model, then the PLUME model could be used for Korea nuclear sites in terms of safety assessment.

Advanced I and C system of security level for nuclear power station

International Nuclear Information System (INIS)

Liu Yanyang

2001-01-01

Advanced I and C system of security level using for PWR developed by Framatome and Schneider collective, SPINLINE3, are introduced. The technology is used to outside reactor nuclear measurement system in Qinshan II period. It's succeed benefits by Framatome and Schneider's more years development experience in nuclear power station digitallization security level I and C system field, which improve security and reliability of PWR, and, easy operation and maintains. SPINLINE3 based on digitallization and modularization technical proposal, and covered entireness reactor protect system and correlative control system. The paper also introduce CLARISSE (computer aided design aid) and SCADE (embedded software aid) for developing SPINLINE3. SPINLINE3 fills correlative IS and rule, based on software and hardware unit which certificate and launch into operation. After brief review of Framatome and Schneider's experience, the paper are introducing design guideline, application technology and how to fill demand of security level I and C system

Status of commercial nuclear high-level waste disposal. Special report

International Nuclear Information System (INIS)

Dau, G.J.; Williams, R.F.

1976-09-01

The results of this review, presented in the form of a functional description of high level waste management system, shows that technology is available to dispose of nuclear waste safely by several different processes. The most attractive alternative in terms of available technology and shortness of time to demonstrate it at commercial scale is a system that converts the waste to a solid by immobilizing the radioactive elements in a glass matrix. Brief comments are also given on international efforts in high level waste management and advanced disposal concepts

Analytical theory for the nuclear level shift of hadronic atoms

International Nuclear Information System (INIS)

Kudryavtsev, A.E.; Lisin, V.I.; Popov, V.S.

1982-01-01

The spectrum problem in the Coulomb potential distorted at small distances is considered. Nuclear shifts of 3-levels in p anti p and Σ - p atoms are calculated. The probabilities of radiative transitions from p-states to the shifted s-states in hadronic atom are also given. It is shown that the reconstruction of atomic levels switches to oscillation regime when absorption increases. The limits of applicability of the perturbation theory in terms of the scattering length for different values of absorption is discussed. An exactly solvable model, Coulomb plus Yamaguchi potential, is considered

Scale-up considerations relevant to experimental studies of nuclear waste-package behavior

International Nuclear Information System (INIS)

Coles, D.G.; Peters, R.D.

1986-04-01

Results from a study that investigated whether testing large-scale nuclear waste-package assemblages was technically warranted are reported. It was recognized that the majority of the investigations for predicting waste-package performance to date have relied primarily on laboratory-scale experimentation. However, methods for the successful extrapolation of the results from such experiments, both geometrically and over time, to actual repository conditions have not been well defined. Because a well-developed scaling technology exists in the chemical-engineering discipline, it was presupposed that much of this technology could be applicable to the prediction of waste-package performance. A review of existing literature documented numerous examples where a consideration of scaling technology was important. It was concluded that much of the existing scale-up technology is applicable to the prediction of waste-package performance for both size and time extrapolations and that conducting scale-up studies may be technically merited. However, the applicability for investigating the complex chemical interactions needs further development. It was recognized that the complexity of the system, and the long time periods involved, renders a completely theoretical approach to performance prediction almost hopeless. However, a theoretical and experimental study was defined for investigating heat and fluid flow. It was concluded that conducting scale-up modeling and experimentation for waste-package performance predictions is possible using existing technology. A sequential series of scaling studies, both theoretical and experimental, will be required to formulate size and time extrapolations of waste-package performance

Geology of high-level nuclear waste disposal

International Nuclear Information System (INIS)

Roxburgh, I.S.

1988-01-01

The concept of geological disposal is set out by describing the major rock types in terms of their ability to isolate high-level nuclear waste. The advantages and problems posed by particular rock formations are explored and the design and construction of geological repositories is considered, along with the methods used to estimate their safety. It gives special consideration to the use of sea-covered rock and sediment as well as the on-land situation. Throughout the book the various principles and problems inherent in geological disposal are explained and illustrated by reference to a multitude of European and North American case studies, backed up by a large number of tables, figures and an extensive bibliography

Role and position of Nuclear Power Plants Research Institute in nuclear power industry

International Nuclear Information System (INIS)

Metke, E.

1984-01-01

The Nuclear Power Plants Research Institute carries out applied and experimental research of the operating states of nuclear power plants, of new methods of surveillance and diagnosis of technical equipment, it prepares training of personnel, carries out tests, engineering and technical consultancy and the research of automated control systems. The main research programme of the Institute is the rationalization of raising the safety and operating reliability of WWER nuclear power plants. The Institute is also concerned with quality assurance of selected equipment of nuclear power plants and assembly works, with radioactive waste disposal and the decommissioning of nuclear power plants as well as with the preparation and implementation of the nuclear power plant start-up. The Research Institute is developing various types of equipment, such as equipment for the decontamination of the primary part of the steam generator, a continuous analyzer of chloride levels in water, a gas monitoring instrument, etc. The prospects are listed of the Research Institute and its cooperation with other CMEA member countries. (M.D.)

Experimentation of nuclear weapons, releases and storages of radioactive wastes in the Kara sea and in New Zemble

International Nuclear Information System (INIS)

Charmasson, S.

1996-01-01

132 nuclear weapons were tested from 1955 to 1990 in New Zemble. From 1959 to 1993, low level liquid radioactive wastes, low and medium level solid radioactive wastes, reactor core and fuel of submarine and nuclear propelled ships were released in the Kara and the Barentz seas. For these two seas, a recapitulation of the different radioactive sources and the found level of radioactivity of the marine environment are presented. (A.B.). 22 refs. 4 figs., 6 tabs

Application of PSA to Assess the Safety Level of Nuclear Power Plants

International Nuclear Information System (INIS)

Berg, H. P.; Goertz, R.

2000-01-01

This paper reviews the application of PSA in German nuclear power plant regulation. From a fundamental point of view, it has to be mentioned that as stipulated in the corresponding requirements, regulatory decision making in Germany is primarily based on deterministic analyses and evaluations. Therefore, PSA is not used as a stand alone but as a supplementary basis. In this context PSA has developed a valuable tool with continuously growing importance. Level 1+ PSAs are now elaborated for all German nuclear power plants in operation, most of them are already reviewed by the competent supervisory authority and its experts. Current research activities on the federal level primarily concentrate on the further development of the methodology in the areas human factor, common cause failures, accident management measures and reduction of uncertainties in methods and data. (author)

Status of the United States' high-level nuclear waste disposal program

International Nuclear Information System (INIS)

Rusche, B.

1985-01-01

The Nuclear Waste Policy Act of 1982 is a remarkable piece of legislation in that there is general agreement on its key provisions. Nevertheless, this is a program intended to span more than a century, with some choices by Congress, states, Indian tribes and the nuclear power industry yet to be made. The crafters of the Act clearly recognized this. And further, the crafters recognized ''. . .that. . .state, Indian tribe and public participation in the planning and development of repositories is essential in order to promote public confidence in the safety of disposal of such waste and spent fuel . . . High-level radioactive waste and spent nuclear fuel have become major subjects of public concern, and appropriate precautions must be taken to ensure that such waste and spent fuel do not adversely affect the public health and safety and the environment for this or future generations

Nuclear test experimental science

International Nuclear Information System (INIS)

Struble, G.L.; Middleton, C.; Bucciarelli, G.; Carter, J.; Cherniak, J.; Donohue, M.L.; Kirvel, R.D.; MacGregor, P.; Reid, S.

1989-01-01

This report discusses research being conducted at Lawrence Livermore Laboratory under the following topics: prompt diagnostics; experimental modeling, design, and analysis; detector development; streak-camera data systems; weapons supporting research

Nuclear test experimental science

Energy Technology Data Exchange (ETDEWEB)

Struble, G.L.; Middleton, C.; Bucciarelli, G.; Carter, J.; Cherniak, J.; Donohue, M.L.; Kirvel, R.D.; MacGregor, P.; Reid, S. (eds.)

1989-01-01

This report discusses research being conducted at Lawrence Livermore Laboratory under the following topics: prompt diagnostics; experimental modeling, design, and analysis; detector development; streak-camera data systems; weapons supporting research.

Mineral-modeled ceramics for long-term storage of high-level nuclear wastes

International Nuclear Information System (INIS)

Vance, E.R.

1980-01-01

Over the past ten years, Penn State's Materials Research Laboratory has done extensive work on mineral-modeled ceramics for high-level nuclear waste storage. These ceramics are composed of several mineral analogues that form a monolithic polycrystalline aggregate. Mineral-modeling can be made in a similar fashion to nuclear waste glasses, and their naturally occurring analogues are known to last millions, and even billions, of years in hot, wet conditions. It is believed that such ceramics could reduce dispersal of radionuclides by leaching to a minimum

Experimental benchmarking of quantum control in zero-field nuclear magnetic resonance.

Science.gov (United States)

Jiang, Min; Wu, Teng; Blanchard, John W; Feng, Guanru; Peng, Xinhua; Budker, Dmitry

2018-06-01

Demonstration of coherent control and characterization of the control fidelity is important for the development of quantum architectures such as nuclear magnetic resonance (NMR). We introduce an experimental approach to realize universal quantum control, and benchmarking thereof, in zero-field NMR, an analog of conventional high-field NMR that features less-constrained spin dynamics. We design a composite pulse technique for both arbitrary one-spin rotations and a two-spin controlled-not (CNOT) gate in a heteronuclear two-spin system at zero field, which experimentally demonstrates universal quantum control in such a system. Moreover, using quantum information-inspired randomized benchmarking and partial quantum process tomography, we evaluate the quality of the control, achieving single-spin control for 13 C with an average fidelity of 0.9960(2) and two-spin control via a CNOT gate with a fidelity of 0.9877(2). Our method can also be extended to more general multispin heteronuclear systems at zero field. The realization of universal quantum control in zero-field NMR is important for quantum state/coherence preparation, pulse sequence design, and is an essential step toward applications to materials science, chemical analysis, and fundamental physics.

Experimental and computational investigation of flow of pebbles in a pebble bed nuclear reactor

Science.gov (United States)

Khane, Vaibhav B.

The Pebble Bed Reactor (PBR) is a 4th generation nuclear reactor which is conceptually similar to moving bed reactors used in the chemical and petrochemical industries. In a PBR core, nuclear fuel in the form of pebbles moves slowly under the influence of gravity. Due to the dynamic nature of the core, a thorough understanding about slow and dense granular flow of pebbles is required from both a reactor safety and performance evaluation point of view. In this dissertation, a new integrated experimental and computational study of granular flow in a PBR has been performed. Continuous pebble re-circulation experimental set-up, mimicking flow of pebbles in a PBR, is designed and developed. Experimental investigation of the flow of pebbles in a mimicked test reactor was carried out for the first time using non-invasive radioactive particle tracking (RPT) and residence time distribution (RTD) techniques to measure the pebble trajectory, velocity, overall/zonal residence times, flow patterns etc. The tracer trajectory length and overall/zonal residence time is found to increase with change in pebble's initial seeding position from the center towards the wall of the test reactor. Overall and zonal average velocities of pebbles are found to decrease from the center towards the wall. Discrete element method (DEM) based simulations of test reactor geometry were also carried out using commercial code EDEM(TM) and simulation results were validated using the obtained benchmark experimental data. In addition, EDEM(TM) based parametric sensitivity study of interaction properties was carried out which suggests that static friction characteristics play an important role from a packed/pebble beds structural characterization point of view. To make the RPT technique viable for practical applications and to enhance its accuracy, a novel and dynamic technique for RPT calibration was designed and developed. Preliminary feasibility results suggest that it can be implemented as a non

Methods of experimental settlement of contradicting data in evaluated nuclear data libraries

Directory of Open Access Journals (Sweden)

V. A. Libman

2016-12-01

Full Text Available The latest versions of the evaluated nuclear data libraries (ENDLs have contradictions concerning data about neutron cross sections. To resolve this contradiction we propose the method of experimental verification. This method is based on using of the filtered neutron beams and following measurement of appropriate samples. The basic idea of the method is to modify the suited filtered neutron beam so that the differences between the neutron cross sections in accordance with different ENDLs become measurable. Demonstration of the method is given by the example of cerium, which according to the latest versions of four ENDLs has significantly different total neutron cross section.

Recent Advances in Low-Level Nuclear Measurements at the CEA

International Nuclear Information System (INIS)

Mahe, C.; Lamadie, F.; Le Goaller, C.

2009-01-01

For several years the CEA has been performing nuclear measurements at different stages of decommissioning projects. The characterization tools initially developed for high-level radioactive waste analysis must be adapted to a new area of application: low-level measurements. Recent technical improvements in gamma imaging, gamma spectrometry detectors, and data analysis make it possible to provide relevant radiological data for waste management, as well as to develop robust and optimized decommissioning scenarios from the initial dose rate mapping to the final declared activity. These techniques have been implemented at various nuclear sites for both trial measurement campaigns and expert investigations to localize residual contamination, to identify the radioelements and to provide an accurate estimate of the declarable activity. Different types of measurements and devices have been used: gamma cameras, coded aperture techniques, alpha imaging prototypes, gamma spectrometry detectors (CdZnTe, HPGe, NaI, and LaBr 3 ), dose rate cartography, and calculation codes (Mercure, MCNP, etc.), all of which provide complementary data for radioactive waste categorization. This paper describes the latest developments and methods deployed on decommissioning projects focusing on low-level in situ applications. Waste drum characterization and in situ glove box measurements are discussed and the technologies and performance of gamma imaging systems, gamma spectrometry detectors, calculation codes and software are described. The paper concludes with a review of future developments and tests necessary for these applications. (authors)

Spin assignments of nuclear levels above the neutron binding energy in $^{88}$Sr

CERN Multimedia

Neutron resonances reveal nuclear levels in the highly excited region of the nucleus around the neutron binding energy. Nuclear level density models are therefore usually calibrated to the number of observed levels in neutron-induced reactions. The gamma-ray cascade from the decay of the highly excited compound nucleus state to the ground state show dierences dependent on the initial spin. This results in a dierence in the multiplicity distribution which can be exploited. We propose to use the 4${\\pi}$ total absorption calorimeter (TAC) at the n TOF facility to determine the spins of resonances formed by neutrons incident on a metallic $^{87}$Sr sample by measuring the gamma multiplicity distributions for the resolved resonances. In addition we would like to use the available enriched $^{87}$Sr target for cross section measurements with the C$\\scriptscriptstyle{6}$D$\\scriptscriptstyle{6}$ detector setup.

The role of nuclear reaction theory and data in nuclear energy and safety applications

International Nuclear Information System (INIS)

Schmidt, J.J.

1993-01-01

The nuclear data requirements for nuclear fission reactor design and safety computations are so large that they cannot be satisfied by experimental measurements alone. Nuclear reaction theories and models have recently been developed and refined to the extent, that, with suitable parametrisation and fitting to accurately known experimental data, they can be used for filling gaps in the available experimental nuclear data base as well as for bulk computations of nuclear reaction, e.g. activation cross sections. The concurrent rapid development of ever more powerful mainframe and personal computers has stimulated the development of comprehensive nuclear model computer codes. A representative selection of such codes will be presented in the lectures and computer exercises of this Workshop. In order to fulfill nuclear data requirements of the nineties and, at the same time, develop improved tools for nuclear physics teaching at developing country universities it will be required and a major future task of the IAEA nuclear data programme to develop computer files of ''best'' sets of nuclear parameters for standardised input to nuclear model computations of nuclear data. Nuclear scientists from developing countries can make substantial contributions to this project. (author). 25 refs

Dose estimation for nuclear power plant 4 accident in Taiwan at Fukushima nuclear meltdown emission level

International Nuclear Information System (INIS)

Tang, Mei-Ling; Tsuang, Ben-Jei; Kuo, Pei-Hsuan

2016-01-01

An advanced Gaussian trajectory dispersion model is used to evaluate the evacuation zone due to a nuclear meltdown at the Nuclear Power Plant 4 (NPP4) in Taiwan, with the same emission level as that occurred at Fukushima nuclear meltdown (FNM) in 2011. Our study demonstrates that a FNM emission level would pollute 9% of the island's land area with annual effective dose ≥50 mSv using the meteorological data on 11 March 2011 in Taiwan. This high dose area is also called permanent evacuation zone (denoted as PEZ). The PEZ as well as the emergency-planning zone (EPZ) are found to be sensitive to meteorological conditions on the event. In a sunny day under the dominated NE wind conditions, the EPZ can be as far as 100 km with the first 7-day dose ≥20 mSv. Three hundred sixty-five daily events using the meteorological data from 11 March 2011 to 9 March 2012 are evaluated. It is found that the mean land area of Taiwan in becoming the PEZ is 11%. Especially, the probabilities of the northern counties/cities (Keelung, New Taipei, Taipei, Taoyuan, Hsinchu City, Hsinchu County and Ilan County) to be PEZs are high, ranging from 15% in Ilan County to 51% in Keelung City. Note that the total population of the above cities/counties is as high as 10 million people. Moreover, the western valleys of the Central Mountain Range are also found to be probable being PEZs, where all of the reservoirs in western Taiwan are located. For example, the probability can be as high as 3% in the far southern-most tip of Taiwan Island in Pingtung County. This shows that the entire populations in western Taiwan can be at risk due to the shortage of clean water sources under an event at FNM emission level, especially during the NE monsoon period. - Highlights: • An advanced Gaussian-type trajectory model to evaluate the evacuation zone at Nuclear Power Plant 4 in Taiwan. • Mean land area of Taiwan in becoming the permanent evacuation zone is 11%. • The probabilities of the northern

Four themes that underlie the high-level nuclear waste management program

International Nuclear Information System (INIS)

Sprecher, W.M.

1989-01-01

In 1982, after years of deliberation and in response to mounting pressures from environmental, industrial, and other groups, the US Congress enacted the Nuclear Waste Policy Act (NWPA) of 1982, which was signed into law by the President in January 1983. That legislation signified a major milestone in the nation's management of high-level nuclear waste, since it represented a consensus among the nation's lawmakers to tackle a problem that had evaded solution for decades. Implementation of the NWPA has proven to be exceedingly difficult, as attested by the discord generated by the US Department of Energy's (DOE's) geologic repository and monitored retrievable storage (MRS) facility siting activities. The vision that motivated the crafters of the 1982 act became blurred as opposition to the law increased. After many hearings that underscored the public's concern with the waste management program, the Congress enacted the Nuclear Waste Policy Amendments Act of 1987 (Amendments Act), which steamlined and focused the program, while establishing three independent bodies: the MRS Review Commission, the Nuclear Waste Technical Review Board, and the Office of the Nuclear Waste Negotiator. Yet, even as the program evolves, several themes characterizing the nation's effort to solve the waste management problem continue to prevail. The first of these themes has to do with social consciousness, and the others that follow deal with technical leadership, public involvement and risk perceptions, and program conservatism

Experimental approach to explosive nucleosynthesis

International Nuclear Information System (INIS)

Kubono, S.

1991-07-01

Recent development of experimental studies on explosive nucleosynthesis, especially the rapid proton process and the primordial nucleosynthesis were discussed with a stress on unstable nuclei. New development in the experimental methods for the nuclear astrophysics is also discussed which use unstable nuclear beams. (author)

Experimental vibration level analysis of a Francis turbine

International Nuclear Information System (INIS)

Bucur, D M; Dunca, G; Calinoiu, C

2012-01-01

In this study the vibration level of a Francis turbine is investigated by experimental work in site. Measurements are carried out for different power output values, in order to highlight the influence of the operation regimes on the turbine behavior. The study focuses on the turbine shaft to identify the mechanical vibration sources and on the draft tube in order to identify the hydraulic vibration sources. Analyzing the vibration results, recommendations regarding the operation of the turbine, at partial load close to minimum values, in the middle of the operating domain or close to maximum values of electric power, can be made in order to keep relatively low levels of vibration. Finally, conclusions are drawn in order to present the real sources of the vibrations.

Experimental and analytical studies on soil-structure interaction behavior of nuclear reactor building

International Nuclear Information System (INIS)

Tsushima, Y.

1978-01-01

The purpose of this study is to estimate damping effects due to soil-structure interaction by the dissipation of vibrational energy to the ground through the foundation in a building with a short fundamental period such as a nuclear reactor building. The author performed experimental and analytical studies on the vibrational characteristics of model steel structures ranging from one to four stories high erected on the rigid base and located on soil, which are simulated from the vibrational characteristics of a prototype reactor building: the former study is to obtain damping effects due to inner friction of steel frames and the latter to obtain radiation damping effects due to soil-structure interaction. The author also touches upon the results of experiments performed on a BWR-type reactor building in 1974, which showed damping ratios higher than 20% of those in fundamental modes. Then the author attempts to estimate the damping effects of the reactor building by his own method proposed in the report. Through these studies the author finally concludes that the experimental damping effects are remarkable in the lower modes by the energy dissipation and the analytical results show a fairly good fit to the experimental ones

On experimental determination of characteristics of nuclear fusion reactions from mu-molecular resonance states

International Nuclear Information System (INIS)

Bystritskij, V.M.; Pen'kov, F.M.

1997-01-01

Charge-nonsymmetrical deuterium-helium muon complexes (dμHe) are studied. A method is proposed for experimentally determining the rates of nuclear fusion reactions in dμHe molecules in the J=1 and J=0 states (J is the orbital moment of the system) and the partial rates for radiative decay of these complexes in these states. Experiments are supposed to be carried out at meson factories with gaseous and cryogenic targets filled with a mixture of deuterium and helium

Facilities for post-irradiation examination of experimental fuel elements at Chalk River Nuclear Laboratories

International Nuclear Information System (INIS)

Mizzan, E.; Chenier, R.J.

1979-10-01

Expansion of post-irradiation facilities at the Chalk River Nuclear Laboratories and steady improvement in hot-cell techniques and equipment are providing more support to Canada's reactor fuel development program. The hot-cell facility primarily used for examination of experimental fuels averages a quarterly throughput of 40 elements and 110 metallographic specimens. New developments in ultrasonic testing, metallographic sample preparation, active storage, active waste filtration, and fissile accountability are coming into use to increase the efficiency and safety of hot-cell operations. (author)

Realistic microscopic level densities for spherical nuclei

International Nuclear Information System (INIS)

Cerf, N.

1994-01-01

Nuclear level densities play an important role in nuclear reactions such as the formation of the compound nucleus. We develop a microscopic calculation of the level density based on a combinatorial evaluation from a realistic single-particle level scheme. This calculation makes use of a fast Monte Carlo algorithm allowing us to consider large shell model spaces which could not be treated previously in combinatorial approaches. Since our model relies on a microscopic basis, it can be applied to exotic nuclei with more confidence than the commonly used semiphenomenological formuals. An exhaustive comparison of our predicted neutron s-wave resonance spacings with experimental data for a wide range of nuclei is presented

Nuclear Data Sheets for A = 196

International Nuclear Information System (INIS)

Huang Xiaolong

2007-01-01

The 1998 version of nuclear data sheets for A = 196 has been revised and updated on the basis of the experimental results from various decay and reaction studies before January 2006. The experimental data for all known nuclei of A = 196 (Os,Ir,Pt,Au,Hg, Tl,Pb,Bi,Po,At,Rn) have been reevaluated. The experimental methods, references,Jπ arguments,and necessary comments are given in the text. Summary band structure drawings and level schemes from both radioactive decay and reaction studies are presented. Also of special interest are the new identification of superdeformed bands in 196 Pb and 196 Bi

A method for assay of special nuclear material in high level liquid waste streams

International Nuclear Information System (INIS)

Venkata Subramani, C.R.; Swaminathan, K.; Asuvathraman, R.; Kutty, K.V.G.

2003-01-01

The assay of special nuclear material in the high level liquid waste streams assumes importance as this is the first stage in the extraction cycle and considerable losses of plutonium could occur here. This stream contains all the fission products as also the minor actinides and hence normal nuclear techniques cannot be used without prior separation of the special nuclear material. This paper presents the preliminary results carried out using wavelength dispersive x-ray fluorescence as part of the developmental efforts to assay SNM in these streams by instrumental techniques. (author)

Mathematical analysis of compressive/tensile molecular and nuclear structures

Science.gov (United States)

Wang, Dayu

Mathematical analysis in chemistry is a fascinating and critical tool to explain experimental observations. In this dissertation, mathematical methods to present chemical bonding and other structures for many-particle systems are discussed at different levels (molecular, atomic, and nuclear). First, the tetrahedral geometry of single, double, or triple carbon-carbon bonds gives an unsatisfying demonstration of bond lengths, compared to experimental trends. To correct this, Platonic solids and Archimedean solids were evaluated as atoms in covalent carbon or nitrogen bond systems in order to find the best solids for geometric fitting. Pentagonal solids, e.g. the dodecahedron and icosidodecahedron, give the best fit with experimental bond lengths; an ideal pyramidal solid which models covalent bonds was also generated. Second, the macroscopic compression/tension architectural approach was applied to forces at the molecular level, considering atomic interactions as compressive (repulsive) and tensile (attractive) forces. Two particle interactions were considered, followed by a model of the dihydrogen molecule (H2; two protons and two electrons). Dihydrogen was evaluated as two different types of compression/tension structures: a coaxial spring model and a ring model. Using similar methods, covalent diatomic molecules (made up of C, N, O, or F) were evaluated. Finally, the compression/tension model was extended to the nuclear level, based on the observation that nuclei with certain numbers of protons/neutrons (magic numbers) have extra stability compared to other nucleon ratios. A hollow spherical model was developed that combines elements of the classic nuclear shell model and liquid drop model. Nuclear structure and the trend of the "island of stability" for the current and extended periodic table were studied.

Nuclear reactions video (knowledge base on low energy nuclear physics)

International Nuclear Information System (INIS)

Zagrebaev, V.; Kozhin, A.

1999-01-01

The NRV (nuclear reactions video) is an open and permanently extended global system of management and graphical representation of nuclear data and video-graphic computer simulation of low energy nuclear dynamics. It consists of a complete and renewed nuclear database and well known theoretical models of low energy nuclear reactions altogether forming the 'low energy nuclear knowledge base'. The NRV solves two main problems: 1) fast and visualized obtaining and processing experimental data on nuclear structure and nuclear reactions; 2) possibility for any inexperienced user to analyze experimental data within reliable commonly used models of nuclear dynamics. The system is based on the realization of the following principal things: the net and code compatibility with the main existing nuclear databases; maximal simplicity in handling: extended menu, friendly graphical interface, hypertext description of the models, and so on; maximal visualization of input data, dynamics of studied processes and final results by means of real three-dimensional images, plots, tables and formulas and a three-dimensional animation. All the codes are composed as the real Windows applications and work under Windows 95/NT

Experimental and analytical studies for a BWR nuclear reactor building evaluation of soil-structure interaction behavior

International Nuclear Information System (INIS)

Mizuno, N.; Tsushima, Y.

1975-01-01

The purpose of this paper is to evaluate the spatial characteristics of dynamic properties, especially soil-structure interaction behavior, or the BWR nuclear reactor building by experimental and analytical studies. An analytical method (SMIRT-1 Paper K 2/4) for estimating the damping effects is reported. The complex damping is used, because the so-called structural damping may be more suitable for estimating the damping effects of an elastic structure. H. Tajimi's theory is used for estimating the dynamical soil-foundation stiffness with the dissipation of vibrational energy on the elastic half-space soil. An approximate explanation is presented in regard to the more developmental mathematical method for estimating the damping effects than the above-mentioned previous method, which is 'Modes Superposition Method for Multi-Degrees of Freedom System' with the constant complex stiffness showing the structural damping effects and the dynamical soil-foundation stiffness approximated by the linear or quadratic functions of the eigenvalues. Next, an approximate explanation is presented in regard to the experimental results of the No.1 reactor building (BWR) of Hamaoka Nuclear Power Station, The Chubu Electric Power Co., Ltd. The regression analyses of the experimental resonance curves by one degree system show that the critical damping ratio is larger than the 0.10 used in the design for the fundamental natural period. It is attempted to simulate the experimental results by the above-mentioned method. The simulated model is a fourty-eight degrees of freedom spring mass system because of the eight masses for the eight floors including the base foundation and the six degrees of freedom for a mass

Dose estimation for nuclear power plant 4 accident in Taiwan at Fukushima nuclear meltdown emission level.

Science.gov (United States)

Tang, Mei-Ling; Tsuang, Ben-Jei; Kuo, Pei-Hsuan

2016-05-01

An advanced Gaussian trajectory dispersion model is used to evaluate the evacuation zone due to a nuclear meltdown at the Nuclear Power Plant 4 (NPP4) in Taiwan, with the same emission level as that occurred at Fukushima nuclear meltdown (FNM) in 2011. Our study demonstrates that a FNM emission level would pollute 9% of the island's land area with annual effective dose ≥50 mSv using the meteorological data on 11 March 2011 in Taiwan. This high dose area is also called permanent evacuation zone (denoted as PEZ). The PEZ as well as the emergency-planning zone (EPZ) are found to be sensitive to meteorological conditions on the event. In a sunny day under the dominated NE wind conditions, the EPZ can be as far as 100 km with the first 7-day dose ≥20 mSv. Three hundred sixty-five daily events using the meteorological data from 11 March 2011 to 9 March 2012 are evaluated. It is found that the mean land area of Taiwan in becoming the PEZ is 11%. Especially, the probabilities of the northern counties/cities (Keelung, New Taipei, Taipei, Taoyuan, Hsinchu City, Hsinchu County and Ilan County) to be PEZs are high, ranging from 15% in Ilan County to 51% in Keelung City. Note that the total population of the above cities/counties is as high as 10 million people. Moreover, the western valleys of the Central Mountain Range are also found to be probable being PEZs, where all of the reservoirs in western Taiwan are located. For example, the probability can be as high as 3% in the far southern-most tip of Taiwan Island in Pingtung County. This shows that the entire populations in western Taiwan can be at risk due to the shortage of clean water sources under an event at FNM emission level, especially during the NE monsoon period. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Determination of leveled costs of electric generation for gas plants, coal and nuclear; Determinacion de costos nivelados de generacion electrica para plantas de gas, carbon y nucleares

Energy Technology Data Exchange (ETDEWEB)

Alonso V, G.; Palacios H, J.C.; Ramirez S, J.R.; Gomez, A. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: galonso@nuclear.inin.mx

2005-07-01

The present work analyzes the leveled costs of electric generation for different types of nuclear reactors known as Generation III, these costs are compared with the leveled costs of electric generation of plants with the help of natural gas and coal. In the study several discount rates were used to determine their impact in the initial investment. The obtained results are comparable with similar studies and they show that it has more than enough the base of the leveled cost the nuclear option it is quite competitive in Mexico. Also in this study it is also thinks about the economic viability of a new nuclear power station in Mexico. (Author)

Neutron dosimetry in EDF experimental surveillance programme for VVER-440 nuclear power plants

International Nuclear Information System (INIS)

Brumovsky, M.; Erben, O.; Novosad, P.; Zerola, L.; Hogel, J.; Trollat, C.

2001-01-01

Fourteen chains containing experimental surveillance material specimens of the VVER 440/213 nuclear power reactor pressure vessels were irradiated in the surveillance channels of the Nuclear Power Plant Dukovany in the Czech Republic. The irradiation periods were one, two or three cycles. The chains contained different number and types of containers, the omitted ones were replaced by chain elements. All of the containers were instrumented with wire neutron fluence detectors, some of the containers in the chain had spectrometric sets of neutron fluence monitors. For the absolute fluence values evaluation it was taken into account time history of the reactor power and local changes of the neutron flux along the reactor core height, correction factors due to the orientation of monitors with respect to the reactor core centre. Unfolding programs SAND-II or BASA-CF were used. The relative axial fluence distribution was obtained from the O-wire measurements. Neutron fluence values above 0.5 MeV energy and above 1.0 MeV energy in the container axis on the axial positions of the sample centres and fluence values in the geometric centre of the samples was calculated making use the exponential attenuation model of the incident neutron beam. Received fast neutron fluence values can be used as reference values to all VVER-440 type 213 nuclear power plant reactors. (author)

Nuclear Level Mixing: From a Curiosity to Applications in Nuclear Physics, Solid State Physics and Gamma Optics

International Nuclear Information System (INIS)

Neyens, Gerda

2001-01-01

The history of 'Nuclear Level Mixing' is closely related to the research that Prof. Coussement performed during the last 25 years. In particular, the impact of this quantum mechanical concept on different research fields will be discussed. Without going in detail, we aim to give the reader an idea of how one single concept may lead to different discoveries

Chemical digestion of low level nuclear solid waste material

International Nuclear Information System (INIS)

Cooley, C.R.; Lerch, R.E.

1976-01-01

A chemical digestion for treatment of low level combustible nuclear solid waste material is provided and comprises reacting the solid waste material with concentrated sulfuric acid at a temperature within the range of 230 0 --300 0 C and simultaneously and/or thereafter contacting the reacting mixture with concentrated nitric acid or nitrogen dioxide. In a special embodiment spent ion exchange resins are converted by this chemical digestion to noncombustible gases and a low volume noncombustible residue. 6 claims, no drawings

International conference: Features of nuclear excitation states and mechanisms of nuclear reactions. 51. Meeting on nuclear spectroscopy and nuclear structure. The book of abstracts

International Nuclear Information System (INIS)

2001-01-01

Results of the LI Meeting on Nuclear Spectroscopy and Nuclear Structure are presented. Properties of excited states of atomic nuclei and mechanisms of nuclear reactions are considered. Studies on the theory of nucleus and fundamental interactions pertinent to experimental study of nuclei properties and mechanisms of nuclear reactions, technique and methods of experiment, application of nuclear-physical method, are provided [ru

Measurement of excited states in 71Ge via (p, nγ) reaction and density of discrete levels in 71Ge

International Nuclear Information System (INIS)

Razavi, R.; Kakavand, T.; Behkami, A.N.

2008-01-01

In all statistical theories the nuclear level density is the most characteristic quantity and plays an essential role in the study of nuclear structure. In this work, additional experimental information about existing level structure of 71 Ge have been provided through the (p, nγ) reaction and then determined nuclear level density parameters of the Bethe formula and constant temperature model for 71 Ge

Experimental nuclear physics: Progress report, September 1986-July 1987

International Nuclear Information System (INIS)

Hamilton, J.H.

1987-08-01

The research activities of the experimental nuclear structure group at Vanderbilt University carried out under Contract AS05-76ER05034 with the Department of Energy for the period September 1986 to July 1987 are reported here. Research continues in the areas of (1) in-beam γ-ray spectroscopy including cooperations with scientists at Oak Ridge, Univ. of Rochester, Univ. of Koeln, Louisiana State Univ., Univ. of Florida, Idaho Falls, and Univ. of Notre Dame; (2) studies of nuclei far from stability at UNISOR and at the recoil mass spectrometer at the University of Rochester; (3) nucleon transfer reaction and fusion-fission studies with scientists at ORNL, Argonne National Laboratory, Univ. of Michigan, and University of Kansas; (4) theoretical studies with scientists at Univ. Frankfurt, Univ. Tuebingen, Univ. Lund, Brookhaven, Lawrence Berkeley, and ORNL; (5) other studies. In general, abstracts of papers published or submitted for publication in this period make up this report along with brief reports of work in process and complete copies of a few conference papers

Should the U.S. proceed to consider licensing deep geological disposal of high-level nuclear waste

International Nuclear Information System (INIS)

Curtiss, J.R.

1993-01-01

The United States, as well as other countries facing the question of how to handle high-level nuclear waste, has decided that the most appropriate means of disposal is in a deep geologic repository. In recent years, the Radioactive Waste Management Committee of the Nuclear Energy Agency has developed several position papers on the technical achievability of deep geologic disposal, thus demonstrating the serious consideration of deep geologic disposal in the international community. The Committee has not, as yet, formally endorsed disposal in a deep geologic repository as the preferred method of handling high-level nuclear waste. The United States, on the other hand, has studied the various methods of disposing of high-level nuclear waste, and has determined that deep geologic disposal is the method that should be developed. The purpose of this paper is to present a review of the United States' decision on selecting deep geologic disposal as the preferred method of addressing the high-level waste problem. It presents a short history of the steps taken by the U.S. in determining what method to use, discusses the NRC's waste Confidence Decision, and provides information on other issues in the U.S. program such as reconsideration of the final disposal standard and the growing inventory of spent fuel in storage

Gas separation techniques in nuclear facilities

International Nuclear Information System (INIS)

Hioki, Hideaki; Morisue, Tetsuo; Ohno, Masayoshi

1983-01-01

The literatures concerning the gas separation techniques which are applied to the waste gases generated from nuclear power plants and nuclear fuel reprocessing plants, uranium enrichment and the instrumentation of nuclear facilities are reviewed. The gas permeability and gas separation performance of membranes are discussed in terms of rare gas separation. The investigation into the change of the gas permeability and mechanical properties of membranes with exposure to radiation is reported. The theoretical investigation of the separating cells used for the separation of rare gas and the development of various separating cells are described, and the theoretical and experimental investigations concerning rare gas separation using cascades are described. The application of membrane method to nuclear facilities is explained showing the examples of uranium enrichment, the treatment of waste gases from nuclear reactor buildings and nuclear fuel reprocessing plants, the monitoring of low level β-emitters in stacks, the detection of failed fuels and the detection of water leak in fast breeder reactors. (Yoshitake, I.)

Experimental methods of investigation of kinetics and dynamics of nuclear reactors

International Nuclear Information System (INIS)

Costa Oliveira, Jaime M.

1969-03-01

The author presents experimental methods used to study kinetic and dynamic properties of nuclear reactors. Kinetic methods aim at determining characteristic parameters of the behaviour in time of neutrons. Dynamic methods aim at establishing the relationships between the reactor behaviour and its internal and external causes (notably the measurement of transfer functions). The author proposes a classification with respect to the excitation type: periodic excitation (reactivity sinusoidal modulation, source sinusoidal modulation, periodic pulse excitation), non periodic excitation (reactivity monitoring, reactivity linear variation, reactivity variation according to any given law, removal of starting source), random excitation (random reactivity or source excitation), natural fluctuations (alpha-Rossi method, methods of reduced variance, probabilistic methods, correlation methods, spectral analysis method). He also addresses space and energy effects. Applications are reported for low power and power reactors

Nuclear physics research report 1988

International Nuclear Information System (INIS)

1988-01-01

The paper presents the 1988 Nuclear Physics Research Report for the University of Surrey, United Kingdom. The report includes both experimental nuclear structure physics and theoretical nuclear physics research work. The experimental work has been carried out predominantly with the Nuclear Structure Facility at the SERC Daresbury Laboratory, and has concerned nuclear shapes, shape coexistence, shape oscillations, single-particle structures and neutron-proton interaction. The theoretical work has involved nuclear reactions with a variety of projectiles below 1 GeV per nucleon incident energy, and aspects of hadronic interactions at intermediate energies. (U.K.)

Fluctuation properties of nuclear energy levels and widths: comparison of theory with experiment

International Nuclear Information System (INIS)

Bohigas, O.; Haq, R.U.; Pandey, A.

1982-09-01

We analyze the fluctuation properties of nuclear energy levels and widths with new spectrally averaged measures. A remarkably close agreement between the predictions of random-matrix theories and experiment is found

Experimental investigation between attentional-resource effectiveness and perception and diagnosis in nuclear power plants

International Nuclear Information System (INIS)

Ha, Jun Su; Seong, Poong Hyun

2014-01-01

Highlights: • Effectiveness in information searching is measured by two eye-tracking measures. • The relationship between the effectiveness and perception and diagnosis is addressed. • An experimental study is conducted to investigate the relationship. • The experimental results show close correlation. • The eye-tracking measures as inferential measures for perception and diagnosis. - Abstract: Eye-tracking-based measures of attentional-resource effectiveness in information searching such as FIR (fixation to importance ratio) and SAE (selective attention effectiveness) have been developed based on cost-benefit principles. The relationship between the eye-tracking-based measures and perception and diagnosis of operators during operating tasks in main control rooms (MCRs) of nuclear power plants (NPPs) is investigated with experimental studies. The FIR and the SAE, which represent how effectively an operator attends to important information sources, are used as measures of the effectiveness in information searching. Perception failure rate (PFR) and diagnosis score (DS) are used as measures of perception and diagnosis, respectively. Experimental results show that the FIR and the SAE correlate closely with the PFR and the DS, respectively. It is concluded that the FIR and the SAE can be used as inferential measures of perception and diagnosis for human factors in NPP MCRs

Experimental investigation between attentional-resource effectiveness and perception and diagnosis in nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Ha, Jun Su, E-mail: junsu.ha@kustar.ac.ae [Nuclear Engineering Department, Khalifa University of Science, Technology and Research, P.O. Box 127788, Abu Dhabi (United Arab Emirates); Seong, Poong Hyun, E-mail: phseong@kaist.ac.kr [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

2014-10-15

Highlights: • Effectiveness in information searching is measured by two eye-tracking measures. • The relationship between the effectiveness and perception and diagnosis is addressed. • An experimental study is conducted to investigate the relationship. • The experimental results show close correlation. • The eye-tracking measures as inferential measures for perception and diagnosis. - Abstract: Eye-tracking-based measures of attentional-resource effectiveness in information searching such as FIR (fixation to importance ratio) and SAE (selective attention effectiveness) have been developed based on cost-benefit principles. The relationship between the eye-tracking-based measures and perception and diagnosis of operators during operating tasks in main control rooms (MCRs) of nuclear power plants (NPPs) is investigated with experimental studies. The FIR and the SAE, which represent how effectively an operator attends to important information sources, are used as measures of the effectiveness in information searching. Perception failure rate (PFR) and diagnosis score (DS) are used as measures of perception and diagnosis, respectively. Experimental results show that the FIR and the SAE correlate closely with the PFR and the DS, respectively. It is concluded that the FIR and the SAE can be used as inferential measures of perception and diagnosis for human factors in NPP MCRs.

Experimental and Theoretical Dynamic Study of the Aagesta Nuclear Power Station

Energy Technology Data Exchange (ETDEWEB)

Bliselius, P A; Vollmer, H; Aakerhielm, F

1969-12-15

The report presents a final review and summary of all dynamic investigations of the Aagesta nuclear power station. Special attention is paid to the final and unpublished experiments performed in 1965-66. These experiments are discussed and compared to the theoretical predictions. Transfer functions and step responses were measured by perturbations in reactivity and steam load. Three methods were used for transfer function measurements: step functions, trapeze waves and multifrequency functions based on the pseudo-random binary sequence (PRBS). From the frequency analysis we found that the different perturbation methods led to quite consistent results. For the Agesta application the PRBS method is demonstrated to be an accurate and practical method for obtaining experimental transfer functions. The step technique did not give satisfactory results for frequencies above approximately 0.01 Hz. From the static check of the model we may conclude that the experiments agree fairly well mutually and with theory. The measured reactivity coefficients tend to be smaller than the predicted ones. The predicted transients compare well with the measured ones. However, there is a tendency to more peaked power transients from the model. This is believed to be due to the assumption that the moderator could be regarded as one channel. The dynamic experiments carried out at the Agesta nuclear power station demonstrate both the inherent stability and the safety of this plant.

Parity dependence of the nuclear level density at high excitation

International Nuclear Information System (INIS)

Rao, B.V.; Agrawal, H.M.

1995-01-01

The basic underlying assumption ρ(l+1, J)=ρ(l, J) in the level density function ρ(U, J, π) has been checked on the basis of high quality data available on individual resonance parameters (E 0 , Γ n , J π ) for s- and p-wave neutrons in contrast to the earlier analysis where information about p-wave resonance parameters was meagre. The missing level estimator based on the partial integration over a Porter-Thomas distribution of neutron reduced widths and the Dyson-Mehta Δ 3 statistic for the level spacing have been used to ascertain that the s- and p-wave resonance level spacings D(0) and D(1) are not in error because of spurious and missing levels. The present work does not validate the tacit assumption ρ(l+1, J)=ρ(l, J) and confirms that the level density depends upon parity at high excitation. The possible implications of the parity dependence of the level density on the results of statistical model calculations of nuclear reaction cross sections as well as on pre-compound emission have been emphasized. (orig.)

RADIATION EFFECTS IN NUCLEAR WASTE MATERIALS

International Nuclear Information System (INIS)

Weber, William J.

2000-01-01

The objective of this research was to develop fundamental understanding and predictive models of radiation effects in glasses and ceramics at the atomic, microscopic, and macroscopic levels, as well as an understanding of the effects of these radiation-induced solid-state changes on dissolution kinetics (i.e., radionuclide release). The research performed during the duration of this project has addressed many of the scientific issues identified in the reports of two DOE panels [1,2], particularly those related to radiation effects on the structure of glasses and ceramics. The research approach taken by this project integrated experimental studies and computer simulations to develop comprehensive fundamental understanding and capabilities for predictive modeling of radiation effects and dissolution kinetics in both glasses and ceramics designed for the stabilization and immobilization of high-level tank waste (HLW), plutonium residues and scraps, surplus weapons plutonium, other actinides, and other highly radioactive waste streams. Such fundamental understanding is necessary in the development of predictive models because all experimental irradiation studies on nuclear waste materials are ''accelerated tests'' that add a great deal of uncertainty to predicted behavior because the damage rates are orders of magnitude higher than the actual damage rates expected in nuclear waste materials. Degradation and dissolution processes will change with damage rate and temperature. Only a fundamental understanding of the kinetics of all the physical and chemical processes induced or affected by radiation will lead to truly predictive models of long-term behavior and performance for nuclear waste materials. Predictive models of performance of nuclear waste materials must be scientifically based and address both radiation effects on structure (i.e., solid-state effects) and the effects of these solid-state structural changes on dissolution kinetics. The ultimate goal of this

Determination of the excess of reactivity in a nuclear configuration and its influence on the power level

International Nuclear Information System (INIS)

Zuniga, Agustin; Tapia, Jose

2014-01-01

This work presents experimental results which show that the critical position of a given nuclear configuration changes with the reactor power (expressed by the current measurement). Thus, if the current is 0.6 x 10 -11 A (1 W), then the critical position is, BC1 = 0.0 % while 0.6 x 10 -9 A (100 W), BC1= 46.5 %. The difference is apparent because under a current of 10 -10 A, the reactivity is not significant. Therefore, it is recommended that for reactors like the RP-10 with a lot of neutrons at the 'background' level, the excess reactivity must be measured in current as 0.6 x 10 -9 A (100 W) not less. Finally, the excess of reactivity for the N o 42 configuration was determined, which was 3032 pcm with uncertainty less than 1 %. (authors).

A new experimental setup established for low-energy nuclear astrophysics studies

International Nuclear Information System (INIS)

Chen, S.Z.; Xu, S.W.; He, J.J.; Hu, J.; Rolfs, C.E.; Zhang, N.T.; Ma, S.B.; Zhang, L.Y.; Hou, S.Q.; Yu, X.Q.; Ma, X.W.

2014-01-01

An experimental setup for low-energy nuclear astrophysics studies has been recently established at the Institute of Modern Physics (IMP), Lanzhou, China. The driver machine is a 320 kV high voltage platform, which can provide intense currents of proton, alpha and many heavy ion beams. The energy of a proton beam was calibrated against the nominal platform high voltage by using a well-known resonant reaction of 11 B(p,γ) 12 C and a non-resonant reaction 12 C(p,γ) 13 N. The accuracy was achieved to be better than ±0.5 keV. The detection system consists of a Clover-type high-purity germanium detector, a silicon detector and a plastic scintillator. The performance of the detectors was tested by several experiments. The astrophysical S-factors of the 7 Li(p,γ) 8 Be and 7 Li(p,α) 3 He reactions were measured with this new setup, and our data agree with the values found in the literature. In addition, the upgrade of our driver machine and experimental setup has been discussed. As a future goal, a fascinating National Deep Underground Laboratory in China, the deepest underground laboratory all over the world, is prospected

Experimental realization of Shor's quantum factoring algorithm using nuclear magnetic resonance.

Science.gov (United States)

Vandersypen, L M; Steffen, M; Breyta, G; Yannoni, C S; Sherwood, M H; Chuang, I L

The number of steps any classical computer requires in order to find the prime factors of an l-digit integer N increases exponentially with l, at least using algorithms known at present. Factoring large integers is therefore conjectured to be intractable classically, an observation underlying the security of widely used cryptographic codes. Quantum computers, however, could factor integers in only polynomial time, using Shor's quantum factoring algorithm. Although important for the study of quantum computers, experimental demonstration of this algorithm has proved elusive. Here we report an implementation of the simplest instance of Shor's algorithm: factorization of N = 15 (whose prime factors are 3 and 5). We use seven spin-1/2 nuclei in a molecule as quantum bits, which can be manipulated with room temperature liquid-state nuclear magnetic resonance techniques. This method of using nuclei to store quantum information is in principle scalable to systems containing many quantum bits, but such scalability is not implied by the present work. The significance of our work lies in the demonstration of experimental and theoretical techniques for precise control and modelling of complex quantum computers. In particular, we present a simple, parameter-free but predictive model of decoherence effects in our system.

Experimental investigation of quadrupole virtual photon spectrum

International Nuclear Information System (INIS)

Gouffon, P.

1986-01-01

To test experimentally the quadrupole virtual photon spectrum calculation, the (e,α) excitation function of an isolated 2 + level at 20.14 MeV in 24 Mg was measured. The most recent calculations in DWBA, including nuclear size effects, are compared to this experimental curve. The differential cross section d 2 σ/dΩdE was measured 48 0 , 90 0 , 132 0 in the laboratory system, for total electron energies of 20.0, 20.8, 21.5, 24.0, 26.0, 28.0, 30.0, 32.0, 36.0, and 40.0 MeV. The reduced matrix element B(E2) of the 20,14 MeV level is extracted as a secondary product of this work. (author) [pt

Dose evaluation and establishment of reference levels in activity for nuclear medicine

International Nuclear Information System (INIS)

Ribeiro, Julio Cesar de Souza

2017-01-01

The International Commission on Radiation Protection (ICRP) has emphasized the importance of accurately determining the mean dose levels, or administered activity, received by the patients for each medical procedure that uses ionizing radiation. However, the number of bibliographic references addressing the need to know and optimize these levels is insufficient, or rather limited, which may lead to non-standardizes techniques, a lack of exposures control, and also the increase of associated radiological risks of these procedures. In this context, a software in Visual Basic® of Microsoft© language was developed whose function is to elaborate a method of obtaining the Reference Levels in Activity (RLA) for nuclear medicine patients by determining the third quartile of the examinations carried out. The program also allows obtaining absorbed dose values in critical organs based on patient specificities as age, sex and Body Mass Index (BMI) in order to evaluate the risk involved in each procedure. The main nuclear medicine diagnostic procedures were evaluated through the database of two public hospitals and a private clinic, obtaining the NRAs of each facility, where the software was validated by comparison with the traditionally accepted calculation methods. Due to the results obtained in each installation, in addition to NRA determination, gaps in treatment capacities and unjustified dose variations for the same procedure were identified, indicating the need for optimization. Thus, the developed program is able to provide the estimated values of effective and absorbed doses involved in each procedure, for each patient, providing reference values for nuclear medicine field, not available in the national scenario so far. (author)

Inelastic electron tunneling spectroscopy of a single nuclear spin.

Science.gov (United States)

Delgado, F; Fernández-Rossier, J

2011-08-12

Detection of a single nuclear spin constitutes an outstanding problem in different fields of physics such as quantum computing or magnetic imaging. Here we show that the energy levels of a single nuclear spin can be measured by means of inelastic electron tunneling spectroscopy (IETS). We consider two different systems, a magnetic adatom probed with scanning tunneling microscopy and a single Bi dopant in a silicon nanotransistor. We find that the hyperfine coupling opens new transport channels which can be resolved at experimentally accessible temperatures. Our simulations evince that IETS yields information about the occupations of the nuclear spin states, paving the way towards transport-detected single nuclear spin resonance.

Workshop on the role of natural analogs in geologic disposal of high-level nuclear waste

International Nuclear Information System (INIS)

Murphy, W.M.; Kovach, L.A.

1995-01-01

A workshop on the Role of Natural Analogs in Geologic Disposal of High-Level Nuclear Waste (HLW) was held in San Antonio, Texas, on July 22-25, 1991. It was sponsored by the US Nuclear Regulatory Commission (NRC) and the Center for Nuclear Waste Regulatory Analyses (CNWRA). Invitations to the workshop were extended to a large number of individuals with a variety of technical and professional interests related to geologic disposal of nuclear waste and natural analog studies. The objective of the workshop was to examine the role of natural analog studies in performance assessment, site characterization, and prioritization of research related to geologic disposal of HLW

Nuclear-level densities in the {sup 49}V and {sup 57}Co nuclei on the basis of evaporated-neutron spectra in (p, n) and (d, n) reactions

Energy Technology Data Exchange (ETDEWEB)

Zhuravlev, B. V., E-mail: zhurav@ippe.ru; Titarenko, N. N. [Leipunsky Institute for Physics and Power Engineering (Russian Federation)

2016-03-15

The spectra of neutrons from the reactions {sup 49}Ti(p, n){sup 49}V and {sup 57}Fe (p, n){sup 57}Co were measured in the range of proton energies between 8 and 11 MeV along with their counterparts from the reactions {sup 48}Ti(d, n){sup 49}V and {sup 56}Fe (d, n){sup 57}Co at the deuteron energies of 2.7 and 3.8 MeV. These measurements were conducted with the aid of a time-of-flight fast-neutron spectrometer on the basis of the EGP-15 pulsed tandem accelerator of the Institute for Physics and Power Engineering (IPPE, Obninsk). An analysis of measured data was performed within the statistical equilibrium and preequilibrium models of nuclear reactions. The respective calculations based on the Hauser–Feshbach formalism of statistical theory were carried out with nuclear-level densities given by the generalized superfluid model of the nucleus, the backshifted Fermi-gas model, and the Gilbert–Cameron composite formula. The nuclear-level densities of {sup 49}V and {sup 57}Co and their energy dependences were determined. The results were discussed together with available experimental data and data recommended by model systematics.

Nuclear physics

International Nuclear Information System (INIS)

Kamal, Anwar

2014-01-01

Explains the concepts in detail and in depth. Provides step-by-step derivations. Contains numerous tables and diagrams. Supports learning and teaching with numerous worked examples, questions and problems with answers. Sketches also the historical development of the subject. This textbook explains the experimental basics, effects and theory of nuclear physics. It supports learning and teaching with numerous worked examples, questions and problems with answers. Numerous tables and diagrams help to better understand the explanations. A better feeling to the subject of the book is given with sketches about the historical development of nuclear physics. The main topics of this book include the phenomena associated with passage of charged particles and radiation through matter which are related to nuclear resonance fluorescence and the Moessbauer effect., Gamov's theory of alpha decay, Fermi theory of beta decay, electron capture and gamma decay. The discussion of general properties of nuclei covers nuclear sizes and nuclear force, nuclear spin, magnetic dipole moment and electric quadrupole moment. Nuclear instability against various modes of decay and Yukawa theory are explained. Nuclear models such as Fermi Gas Model, Shell Model, Liquid Drop Model, Collective Model and Optical Model are outlined to explain various experimental facts related to nuclear structure. Heavy ion reactions, including nuclear fusion, are explained. Nuclear fission and fusion power production is treated elaborately.

Chem I Supplement. Chemistry Related to Isolation of High-Level Nuclear Waste.

Science.gov (United States)

Hoffman, Darleane C.; Choppin, Gregory R.

1986-01-01

Discusses some of the problems associated with the safe disposal of high-level nuclear wastes. Describes several waste disposal plans developed by various nations. Outlines the multiple-barrier concept of isolation in deep geological questions associated with the implementation of such a method. (TW)

Fair rules for siting a high-level nuclear waste repository

International Nuclear Information System (INIS)

Easterling, D.

1992-01-01

Geologic repositories are designed to resolve the ever-growing problem of high-level nuclear waste, but these facilities invite intense local opposition due to the perceived severity of the risks and the possibility of stigma effects. This analysis examines whether the perceived fairness of the siting process affects local residents' support for hosting a repository. In particular, a survey of 1,001 Nevada residents is used to test the hypothesis that an individual's willingness to accept a local repository will increase if he or she is convinced that this is the safest disposal option available. A logistic analysis indicates that beliefs regarding relative suitability have an independent effect on the acceptability of a local repository (i.e., Yucca Mountain). The article then considers the question of how to implement an optimizing strategy for siting facilities, comparing an idealized strategy against the original Nuclear Waste Policy Act (NWPA) of 1982 and the Amendments Act of 1987. Although choosing the safest site seems as if it could enhance public acceptance of the repository program, there is currently little prospect of identifying the best option to the high-level waste problem and, as a results, little chance of gaining the public support that is necessary to promote a successful siting outcome. 81 refs., 1 fig., 5 tabs

Spent Fuel Transportation Package Performance Study - Experimental Design Challenges

International Nuclear Information System (INIS)

Snyder, A. M.; Murphy, A. J.; Sprung, J. L.; Ammerman, D. J.; Lopez, C.

2003-01-01

Numerous studies of spent nuclear fuel transportation accident risks have been performed since the late seventies that considered shipping container design and performance. Based in part on these studies, NRC has concluded that the level of protection provided by spent nuclear fuel transportation package designs under accident conditions is adequate. [1] Furthermore, actual spent nuclear fuel transport experience showcase a safety record that is exceptional and unparalleled when compared to other hazardous materials transportation shipments. There has never been a known or suspected release of the radioactive contents from an NRC-certified spent nuclear fuel cask as a result of a transportation accident. In 1999 the United States Nuclear Regulatory Commission (NRC) initiated a study, the Package Performance Study, to demonstrate the performance of spent fuel and spent fuel packages during severe transportation accidents. NRC is not studying or testing its current regulations, a s the rigorous regulatory accident conditions specified in 10 CFR Part 71 are adequate to ensure safe packaging and use. As part of this study, NRC currently plans on using detailed modeling followed by experimental testing to increase public confidence in the safety of spent nuclear fuel shipments. One of the aspects of this confirmatory research study is the commitment to solicit and consider public comment during the scoping phase and experimental design planning phase of this research

Thoughts of the nuclear safety culture and 'star-level' management

International Nuclear Information System (INIS)

Wang Sen

2004-01-01

From the point of view that enterprise management has come into the stage of cultural management, this article divides the contents of nuclear safety culture into target management, safety management, quality management, site management, cost management, authority management, teamwork, information communication and continuous improvement. Each aspect win be classified by five 'star- level's according to the appearance, and the present situation of the company should be assessed with those star-level indices so as to find out the disadvantages. Improvement will follow with the promotion of company management level. (author)

Calculational tools for the evaluation of nuclear cross-section and spectra data

International Nuclear Information System (INIS)

Gardner, M.A.

1985-01-01

A technique based on discrete energy levels rather than energy level densities is presented for nuclear reaction calculations. The validity of the technique is demonstrated via theoretical and experimental agreement for cross sections, isomer-ratios and gamma-ray strength functions. 50 refs., 7 figs

Nuclear models relevant to evaluation

International Nuclear Information System (INIS)

Arthur, E.D.; Chadwick, M.B.; Hale, G.M.; Young, P.G.

1991-01-01

The widespread use of nuclear models continues in the creation of data evaluations. The reasons include extension of data evaluations to higher energies, creation of data libraries for isotopic components of natural materials, and production of evaluations for radiative target species. In these cases, experimental data are often sparse or nonexistent. As this trend continues, the nuclear models employed in evaluation work move towards more microscopically-based theoretical methods, prompted in part by the availability of increasingly powerful computational resources. Advances in nuclear models applicable to evaluation will be reviewed. These include advances in optical model theory, microscopic and phenomenological state and level density theory, unified models that consistently describe both equilibrium and nonequilibrium reaction mechanism, and improved methodologies for calculation of prompt radiation from fission. 84 refs., 8 figs

[Experimental and theoretical nuclear physics]: 1988 Annual report

International Nuclear Information System (INIS)

1988-05-01

This paper describes the highlights of the past year of the Nuclear Physics Laboratory at the University of Washington. Particular topics discussed are: astrophysics, giant resonance, heavy ion induced reactions, fundamental symmetries, nuclear reactions, medium energy reactions, accelerator mass spectrometry, Van de Graaf and ion sources, the booster linac project, instrumentation and computer systems

Parameters affecting level measurement interpretation of nuclear fuel solutions

International Nuclear Information System (INIS)

Hunt, B.A.; Landat, D.A.

1999-01-01

This paper describes a level measurement technique commonly used in the measurement of radioactive liquids and equipment utilised by the inspectors for safeguards purposes. Some of the influencing parameters affecting the measurement results by this technique are characterised. An essential requisite for successful process operations in chemical facilities involving liquids generally require some physical measurements to be made in-line for both process and quality control in order to achieve the necessary final product specifications . In nuclear fuel reprocessing facilities, the same objectives apply coupled however with an additional requirement of achieving nuclear material accountancy and control. In view of the strategic importance of some of the process vessels in nuclear facilities, accountancy has to be supported by volume and density measurements of low uncertainty. Inspectors therefore require instruments which are at the very least as good as or better than operator's equipment. The classical measurement technique and most widely applied for process liquids in nuclear installations is the bubbler probe or dip-tube technique. Here a regulated flow of air passes through tubes inserted to various depths into the vessel and pressure readings are measured which are a function of the presence of liquid height and density of solution in the tank. These readings, taken together with a pre-determined calibration curve are sufficient for the volume and amount of liquor in a tank to be quantified. All measurement equipment and instrumentation are long distances from the tank environment. The key physical parameter to measure at this location is therefore pressure. Equipment designed developed, commissioned and tested in the tank measurement facilities at Ispra and in nuclear installations in Europe, Japan and the USA, house digital pressure transducer modules with manufacture's declared features of better than 0.01% accuracy and long term stability of 0.01% full

Nuclear data services of the Nuclear Data Centers Network available at the National Nuclear Data Center

International Nuclear Information System (INIS)

McLane, V.

1997-01-01

The Nuclear Data Centers Network provides low and medium energy nuclear reaction data to users around the world. Online retrievals are available through the U.S. National Nuclear Data Center, the Nuclear Energy Agency Data Bank, and the IAEA Nuclear Data Section from these extensive bibliographic, experimental data, and evaluated data files. In addition to nuclear reaction data, the various databases also provide nuclear structure and decay data, and other information of interest to users. The WorldWideWeb sites at the National Nuclear Data Center and the NEA Data Bank provide access to some of the Centers' files. (orig.)

Environmental remediation of high-level nuclear waste in geological repository. Modified computer code creates ultimate benchmark in natural systems

International Nuclear Information System (INIS)

Peter, Geoffrey J.

2011-01-01

Isolation of high-level nuclear waste in permanent geological repositories has been a major concern for over 30 years due to the migration of dissolved radio nuclides reaching the water table (10,000-year compliance period) as water moves through the repository and the surrounding area. Repositories based on mathematical models allow for long-term geological phenomena and involve many approximations; however, experimental verification of long-term processes is impossible. Countries must determine if geological disposal is adequate for permanent storage. Many countries have extensively studied different aspects of safely confining the highly radioactive waste in an underground repository based on the unique geological composition at their selected repository location. This paper discusses two computer codes developed by various countries to study the coupled thermal, mechanical, and chemical process in these environments, and the migration of radionuclide. Further, this paper presents the results of a case study of the Magma-hydrothermal (MH) computer code, modified by the author, applied to nuclear waste repository analysis. The MH code verified by simulating natural systems thus, creating the ultimate benchmark. This approach based on processes similar to those expected near waste repositories currently occurring in natural systems. (author)

The Joint Institute for Nuclear Research in Experimental Physics of Elementary Particles

Science.gov (United States)

Bednyakov, V. A.; Russakovich, N. A.

2018-05-01

The year 2016 marks the 60th anniversary of the Joint Institute for Nuclear Research (JINR) in Dubna, an international intergovernmental organization for basic research in the fields of elementary particles, atomic nuclei, and condensed matter. Highly productive advances over this long road clearly show that the international basis and diversity of research guarantees successful development (and maintenance) of fundamental science. This is especially important for experimental research. In this review, the most significant achievements are briefly described with an attempt to look into the future (seven to ten years ahead) and show the role of JINR in solution of highly important problems in elementary particle physics, which is a fundamental field of modern natural sciences. This glimpse of the future is full of justified optimism.

Initial performance assessment of the disposal of spent nuclear fuel and high-level waste stored at Idaho National Engineering Laboratory. Volume 2: Appendices

Energy Technology Data Exchange (ETDEWEB)

Rechard, R.P. [ed.

1993-12-01

This performance assessment characterized plausible treatment options conceived by the Idaho National Engineering Laboratory (INEL) for its spent fuel and high-level radioactive waste and then modeled the performance of the resulting waste forms in two hypothetical, deep, geologic repositories: one in bedded salt and the other in granite. The results of the performance assessment are intended to help guide INEL in its study of how to prepare wastes and spent fuel for eventual permanent disposal. This assessment was part of the Waste Management Technology Development Program designed to help the US Department of Energy develop and demonstrate the capability to dispose of its nuclear waste, as mandated by the Nuclear Waste Policy Act of 1982. The waste forms comprised about 700 metric tons of initial heavy metal (or equivalent units) stored at the INEL: graphite spent fuel, experimental low enriched and highly enriched spent fuel, and high-level waste generated during reprocessing of some spent fuel. Five different waste treatment options were studied; in the analysis, the options and resulting waste forms were analyzed separately and in combination as five waste disposal groups. When the waste forms were studied in combination, the repository was assumed to also contain vitrified high-level waste from three DOE sites for a common basis of comparison and to simulate the impact of the INEL waste forms on a moderate-sized repository, The performance of the waste form was assessed within the context of a whole disposal system, using the U.S. Environmental Protection Agency`s Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes, 40 CFR 191, promulgated in 1985. Though the waste form behavior depended upon the repository type, all current and proposed waste forms provided acceptable behavior in the salt and granite repositories.

Risk perception on management of nuclear high-level and transuranic waste storage

Energy Technology Data Exchange (ETDEWEB)

Dees, Lawrence A. [Colorado Christian Univ., Lakewood, CO (United States)

1994-08-15

The Department of Energy`s program for disposing of nuclear High-Level Waste (HLW) and transuranic (TRU) waste has been impeded by overwhelming political opposition fueled by public perceptions of actual risk. Analysis of these perceptions shows them to be deeply rooted in images of fear and dread that have been present since the discovery of radioactivity. The development and use of nuclear weapons linked these images to reality and the mishandling of radioactive waste from the nations military weapons facilities has contributed toward creating a state of distrust that cannot be erased quickly or easily. In addition, the analysis indicates that even the highly educated technical community is not well informed on the latest technology involved with nuclear HLW and TRU waste disposal. It is not surprising then, that the general public feels uncomfortable with DOE`s management plans for with nuclear HLW and TRU waste disposal. Postponing the permanent geologic repository and use of Monitored Retrievable Storage (MRS) would provide the time necessary for difficult social and political issues to be resolved. It would also allow time for the public to become better educated if DOE chooses to become proactive.

Risk perception on management of nuclear high-level and transuranic waste storage

International Nuclear Information System (INIS)

Dees, L.A.

1994-01-01

The Department of Energy's program for disposing of nuclear High-Level Waste (HLW) and transuranic (TRU) waste has been impeded by overwhelming political opposition fueled by public perceptions of actual risk. Analysis of these perceptions shows them to be deeply rooted in images of fear and dread that have been present since the discovery of radioactivity. The development and use of nuclear weapons linked these images to reality and the mishandling of radioactive waste from the nations military weapons facilities has contributed toward creating a state of distrust that cannot be erased quickly or easily. In addition, the analysis indicates that even the highly educated technical community is not well informed on the latest technology involved with nuclear HLW and TRU waste disposal. It is not surprising then, that the general public feels uncomfortable with DOE's management plans for with nuclear HLW and TRU waste disposal. Postponing the permanent geologic repository and use of Monitored Retrievable Storage (MRS) would provide the time necessary for difficult social and political issues to be resolved. It would also allow time for the public to become better educated if DOE chooses to become proactive

Global nuclear-structure calculations

International Nuclear Information System (INIS)

Moeller, P.; Nix, J.R.

1990-01-01

The revival of interest in nuclear ground-state octupole deformations that occurred in the 1980's was stimulated by observations in 1980 of particularly large deviations between calculated and experimental masses in the Ra region, in a global calculation of nuclear ground-state masses. By minimizing the total potential energy with respect to octupole shape degrees of freedom in addition to ε 2 and ε 4 used originally, a vastly improved agreement between calculated and experimental masses was obtained. To study the global behavior and interrelationships between other nuclear properties, we calculate nuclear ground-state masses, spins, pairing gaps and Β-decay and half-lives and compare the results to experimental qualities. The calculations are based on the macroscopic-microscopic approach, with the microscopic contributions calculated in a folded-Yukawa single-particle potential

Discussion on monitoring items of radionuclides in influents from nuclear power plants

International Nuclear Information System (INIS)

Zhang Yanxia; Li Jin; Liu Jiacheng; Han Shanbiao; Yu Zhengwei

2014-01-01

For the radionuclide monitoring items of effluents from nuclear power plant, this paper makes some comparisons and analysis from three aspects of the international atomic energy general requirements, the routine radionuclide measurement items of China's nuclear power plant and effluents low level radionuclide experimental research results. Finally, it summarizes the necessary items and recommended items of the radionuclide monitoring of effluents from nuclear power plant, which can provide references for the radioactivity monitoring activities of nuclear power plant effluent and the supervisions of regulatory departments. (authors)

Second Mexican School of Nuclear Physics: Notes

International Nuclear Information System (INIS)

Aguilera, E.F.; Chavez L, E.R.; Hess, P.O.

2001-01-01

The II Mexican School of Nuclear Physics which is directed to those last semesters students of the Physics career or post-graduate was organized by the Nuclear Physics Division of the Mexican Physics Society, carrying out at April 16-27, 2001 in the installations of the Institute of Physics and the Institute of Nuclear Sciences, both in the UNAM, and the National Institute of Nuclear Research (ININ). A first school of a similar level in Nuclear Physics, was carried out in Mexico at 1977 as Latin american School of Physics. This book treats about the following themes: Interactions of radiation with matter, Evaluation of uncertainty in experimental data, Particle accelerators, Notions of radiological protection and dosimetry, Cosmic rays, Basis radiation (environmental), Measurement of excitation functions with thick targets and inverse kinematics, Gamma ray technique for to measure the nuclear fusion, Neutron detection with Bonner spectrometer, Energy losses of alpha particles in nickel. It was held the practice Radiation detectors. (Author)

Structural changes in irreversibly densified fused silica: implications for the chemical resistance of high level nuclear waste glasses

International Nuclear Information System (INIS)

Susman, S.; Volin, K.J.; Liebermann, R.C.; Gwanmesia, G.D.; Yanbin Wang

1990-01-01

Energetic photons and energetic particles create changes in the structure of nuclear waste glasses. These can be observed as changes in the average bulk physical properties. For example, exposure of fused silica to high doses of neutron bombardment leads to a maximum average compaction of 3%. However, this does not reveal the true extent of the densification that takes place at a microscopic level. Recent advances in high pressure technology have yielded large samples of fused silica which have been permanently densified under pressure and whose bulk density has been increased by 20%. These specimens have an overall structure that replicates the microstructure of a radiation damaged glass. Measurements have been made for the first time of the structural changes in this pressure densified vitreous silica using neutron diffraction and infrared absorption spectrometry. Extensive alterations in intermediate range order have been observed with consequent anticipated changes in chemical reactivity. The resistance of high level waste glasses to leaching by groundwater must be considered in light of these experimental findings. (author)

French diagnostic reference levels in diagnostic radiology, computed tomography and nuclear medicine: 2004-2008 Review

International Nuclear Information System (INIS)

Roch, P.; Aubert, B.

2013-01-01

After 5 y of collecting data on diagnostic reference levels (DRLs), the Nuclear Safety and Radiation Protection French Inst. (IRSN) presents the analyses of this data. The analyses of the collected data for radiology, computed tomography (CT) and nuclear medicine allow IRSN to estimate the level of regulatory application by health professionals and the representativeness of current DRL in terms of relevant examinations, dosimetric quantities, numerical values and patient morphologies. Since 2004, the involvement of professionals has highly increased, especially in nuclear medicine, followed by CT and then by radiology. Analyses show some discordance between regulatory examinations and clinical practice. Some of the dosimetric quantities used for the DRL setting are insufficient or not relevant enough, and some numerical values should also be reviewed. On the basis of these findings, IRSN formulates recommendations to update regulatory DRL with current and relevant examination lists, dosimetric quantities and numerical values. (authors)

The utility of system-level RAM analysis and standards for the US nuclear waste management system

International Nuclear Information System (INIS)

Rod, S.R.; Adickes, M.D.; Paul, B.K.

1992-03-01

The Department of Energy (DOE) Office of Civilian Radioactive Waste Management (OCRWM) is responsible for developing a system to manage spent nuclear fuel and high-level radioactive waste in accordance with the Nuclear Waste Policy Act of 1982 and its subsequent amendments. Pacific Northwest Laboratory (PNL) is assisting OCRWM in its investigation of whether system-level reliability, availability, and maintainability (RAM) requirements are appropriate for the waste management system and, if they are, what appropriate form should be for such requirements. Results and recommendations are presented

Experimental and numerical characterization of wind-induced pressure coefficients on nuclear buildings and chimney exhausts

Energy Technology Data Exchange (ETDEWEB)

Ricciardi, Laurent, E-mail: laurent.ricciardi@irsn.fr; Gélain, Thomas; Soares, Sandrine

2015-10-15

Highlights: • Experiments on scale models of nuclear buildings and chimney exhausts were performed. • Pressure coefficient fields on buildings are shown for various wind directions. • Evolution of pressure coefficient vs U/W ratio is given for various chimney exhausts. • RANS simulations using SST k–ω turbulence model were performed on most studied cases. • A good agreement is overall observed, with Root Mean Square Deviation lower than 0.15. - Abstract: Wind creates pressure effects on different surfaces of buildings according to their exposure to the wind, in particular at external communications. In nuclear facilities, these effects can change contamination transfers inside the building and can even lead to contamination release into the environment, especially in damaged (ventilation stopped) or accidental situations. The diversity of geometries of facilities requires the use of a validated code for predicting pressure coefficients, which characterize the wind effect on the building walls and the interaction between the wind and chimney exhaust. The first aim of a research program launched by the French Institut de Radioprotection et de Sûreté Nucléaire (IRSN), was therefore to acquire experimental data of the mean pressure coefficients for different geometries of buildings and chimneys through wind tunnel tests and then to validate a CFD code (ANSYS CFX) from these experimental results. The simulations were performed using a steady RANS approach and a two-equation SST k–ω turbulence model. After a mesh sensitivity study for one configuration of building and chimney, a comparison was carried out between the numerical and experimental values for other studied configurations. This comparison was generally satisfactory, averaged over all measurement points, with values of Root Mean Square Deviations lower than 0.15 for most cases.

Experimental facilities and simulation means

International Nuclear Information System (INIS)

Thomas, J.B.

2009-01-01

This paper and its associated series of slides review the experimental facilities and the simulation means used for the development of nuclear reactors in France. These experimental facilities include installations used for the measurement and qualification of nuclear data (mainly cross-sections) like EOLE reactor and Minerve zero power reactor, installations like material testing reactors, installations dedicated to reactor safety experiments like Cabri reactor, and other installations like accelerators (Jannus accelerator, GANIL for instance) that are complementary to neutron irradiations in experimental reactors. The simulation means rely on a series of advanced computer codes: Tripoli-Apollo for neutron transport, Numodis for irradiation impact on materials, Neptune and Cathare for 2-phase fluid dynamics, Europlexus for mechanical structures, and Pleiades (with Alcyone) for nuclear fuels. (A.C.)

Experimental study of vascular embolization with homemade second-level Copper coil

International Nuclear Information System (INIS)

Jiang Hua; Wang Jiaping; Li Yingchun; Tong Yuyun; Yang Qing; Yan Dong; Ding Lili; Yuan Shuguang

2013-01-01

Objective: To evaluate the embolic effect of homemade copper coil in rabbits. Methods: Seventeen New Zealand Big Ear Rabbit was included in this study. After conventional anesthesia, one common carotid artery or subclavian artery was embolized with second-level copper coated platinum microcoils (experimental group) through a 3F catheter, and the other common carotid artery or subclavian artery was embolized with second-level platinum micro-coils (control group) as control. Angiography was processed to observe the extent of vascular occlusion 10 min, 30 min, 3 d, 1 w, 2 w, 4 w, 6 w, and 12 w after embolization respectively. The rabbits were sacrificed to observe thrombosis and pathological change of the embolic artery 3 days, 1 w, 2 w, 4 w, 6 w and 12 w after the embolization. Vascular occlusion and thrombosis were compared between experimental group and the control group by using the exact probability method and rank sum test for statistical analysis. Results: Embolization experiment was successfully implemented in 15 of 17 rabbits. Twenty-one second-level copper coated platinum micro-coils were used in the experimental group, while 19 second-level platinum micro-coils were used in the control group. Ten min and 30 min after embolization, angiography showed that vascular embolization effect was not significantly different between the two groups. The vascular embolization effect of the experiment group was superior to control group 3 d, 1, 2, 4, 6 and 12 w after embolization (P < 0.05). Pathological examination showed that there were a lot of blood clots around the copper coil and in the proximal and distal arterial lumen. Only a small amount of blood clots was found around the platinum coil in the control group. For every time point of observation, thrombosis was more severe in the experiment group than that in the control group (P < 0.05). Conclusion: Second-level copper coated coil can be released with 4F catheter to embolize the vessel, showing good physical

Detailed description of a state system for accounting for and control of nuclear material at the state level

International Nuclear Information System (INIS)

Jones, R.J.

1985-02-01

The purpose of this document is to provide a detailed description of the technical elements of a system for the accounting for and control of nuclear material at the State Authority level which can be used by a state in the establishment of a national system for nuclear material accounting and control. It is expected that a state system designed along the lines described also will assist the IAEA in carrying out its safeguards responsibilities. The scope of this document is limited to descriptions of the technical elements of a state level system concerned with Laws and Regulations, the Information System, and the Establishment of Requirements for Nuclear Material Accounting and Control. The discussion shows the relationship of these technical elements at the state level to the principal elements of an SSAC at the facility levels

Quark deconfinement in nuclei: A review of experimental tests based on nuclear magnetic moment measurements

International Nuclear Information System (INIS)

Stone, N.J.; Rikovska, J.

1988-01-01

The introduction very briefly outlines the basic idea and experimental evidence to suggest that quarks may behave differently in nuclei and in individual nucleons, with possible consequences for the calculation of nuclear magnetic dipole moments. After description of a calculation of moments made using the extreme model of total quark deconfinement (the MIT bag model) attention is focussed on experimental tests and the state of current evidence for more partial quark deconfinement. The arguments of Yamazaki which give an experimental basis for distinguishing quark deconfinement effects from, specifically, effects caused by pion exchange currents, are given in more detail. The reasons underlying choice of nuclei in which meaningful tests may be possible are given. Early claims by Karl et al. to have demonstrated the existence of quark deconfinement in mass 3 nuclei are discussed. The current status of evidence for deconfinement based on orbital g-factor measurements in heavier nuclei is also summarised. Finally some examples are given of possible experiments using recently developed on-line facilities which may provide further tests of these ideas. (orig.)

The effect of preferred music genre selection versus preferred song selection on experimentally induced anxiety levels.

Science.gov (United States)

Walworth, Darcy DeLoach

2003-01-01

The purpose of this study was to investigate the differences of experimentally induced anxiety levels reached by subjects listening to no music (n = 30), subjects listening to music selected by the experimenter from the subject's preferred genre or artist listed as relaxing (n = 30), and subjects listening to a specific song they listed as relaxing (n = 30). Subjects consisted of 90 individuals, male and female, randomly assigned to one of the three groups mentioned above. Subjects in either music group filled out a questionnaire prior to participating in the study indicating their preference of music used for relaxation purposes. Subjects in Experimental Group 1 marked their preferred genres and/or artists, and Experimental Group 2 marked specific songs used for relaxation purposes. While the experimenter hypothesized subjects in Experimental Group 2 would show less anxiety than both the control group and Experimental Group 1, there were no significant differences found between the 2 music groups in anxiety levels reached. However, there was a statistically significant difference between the no music control group and both music groups in the anxiety level reached by subjects. Subjects listening to music, both songs chosen by the experimenter and subject selected songs, showed significantly less anxiety than subjects not listening to music.

Nuclear structure of 54Cr

International Nuclear Information System (INIS)

Saini, S.; Gunye, M.R.

1980-01-01

The large amount of the experimental data accumulated in recent years on the levels of fp-shell nuclei, especially on the properties of the high spin states studied through heavy-ion reactions, needs to be explained systematically on theoretical basis. The exact shell model calculations are not feasible for most of these nuclei. The restricted shell-model calculations, however, do not give a proper account of the experimental data. The nuclear structure of 54 Cr has been investigated in the framework of Hartree-Fock Projection formation employing effective interaction in the configuration space of the full fp-shell. The band-mixed wave functions obtained from the lowest four intrinsic states have been used to compute energy levels and electromagnetic properties. The present calculations give a fairly good account of the available data. (author)

Handbook of nuclear engineering: vol 1: nuclear engineering fundamentals; vol 2: reactor design; vol 3: reactor analysis; vol 4: reactors of waste disposal and safeguards

CERN Document Server

2013-01-01

The Handbook of Nuclear Engineering is an authoritative compilation of information regarding methods and data used in all phases of nuclear engineering. Addressing nuclear engineers and scientists at all academic levels, this five volume set provides the latest findings in nuclear data and experimental techniques, reactor physics, kinetics, dynamics and control. Readers will also find a detailed description of data assimilation, model validation and calibration, sensitivity and uncertainty analysis, fuel management and cycles, nuclear reactor types and radiation shielding. A discussion of radioactive waste disposal, safeguards and non-proliferation, and fuel processing with partitioning and transmutation is also included. As nuclear technology becomes an important resource of non-polluting sustainable energy in the future, The Handbook of Nuclear Engineering is an excellent reference for practicing engineers, researchers and professionals.

Proceedings of the 9. Workshop on Nuclear Physics - Communications of basic nuclear physics

International Nuclear Information System (INIS)

1986-01-01

The abstracts of researches on basic nuclear physics of 9. Workshop on Nuclear Physics in Brazil are presented. Mathematical models and experimental methods for nuclear phenomenon description, such as nuclear excitation and disintegration of several nuclei were discussed. (M.C.K.) [pt

Intracellular calcium levels can regulate Importin-dependent nuclear import

International Nuclear Information System (INIS)

Kaur, Gurpreet; Ly-Huynh, Jennifer D.; Jans, David A.

2014-01-01

Highlights: • High intracellular calcium inhibits Impα/β1- or Impβ1-dependent nuclear protein import. • The effect of Ca 2+ on nuclear import does not relate to changes in the nuclear pore. • High intracellular calcium can result in mislocalisation of Impβ1, Ran and RCC1. - Abstract: We previously showed that increased intracellular calcium can modulate Importin (Imp)β1-dependent nuclear import of SRY-related chromatin remodeling proteins. Here we extend this work to show for the first time that high intracellular calcium inhibits Impα/β1- or Impβ1-dependent nuclear protein import generally. The basis of this relates to the mislocalisation of the transport factors Impβ1 and Ran, which show significantly higher nuclear localization in contrast to various other factors, and RCC1, which shows altered subnuclear localisation. The results here establish for the first time that intracellular calcium modulates conventional nuclear import through direct effects on the nuclear transport machinery

Intracellular calcium levels can regulate Importin-dependent nuclear import

Energy Technology Data Exchange (ETDEWEB)

Kaur, Gurpreet; Ly-Huynh, Jennifer D.; Jans, David A., E-mail: David.Jans@monash.edu

2014-07-18

Highlights: • High intracellular calcium inhibits Impα/β1- or Impβ1-dependent nuclear protein import. • The effect of Ca{sup 2+} on nuclear import does not relate to changes in the nuclear pore. • High intracellular calcium can result in mislocalisation of Impβ1, Ran and RCC1. - Abstract: We previously showed that increased intracellular calcium can modulate Importin (Imp)β1-dependent nuclear import of SRY-related chromatin remodeling proteins. Here we extend this work to show for the first time that high intracellular calcium inhibits Impα/β1- or Impβ1-dependent nuclear protein import generally. The basis of this relates to the mislocalisation of the transport factors Impβ1 and Ran, which show significantly higher nuclear localization in contrast to various other factors, and RCC1, which shows altered subnuclear localisation. The results here establish for the first time that intracellular calcium modulates conventional nuclear import through direct effects on the nuclear transport machinery.

Numerical investigation of high level nuclear waste disposal in deep anisotropic geologic repositories

KAUST Repository

Salama, Amgad; El Amin, Mohamed F.; Sun, Shuyu

2015-01-01

One of the techniques that have been proposed to dispose high level nuclear waste (HLW) has been to bury them in deep geologic formations, which offer relatively enough space to accommodate the large volume of HLW accumulated over the years since

Global trends in nuclear education at the tertiary level

International Nuclear Information System (INIS)

Kemeny, L.G.

2001-01-01

The public perception of nuclear science and engineering and the nuclear industry is today, primarily shaped by radical greens, nuclear-opponents, the media and socio-political opportunists. Only countries with a well diversified tertiary education system embracing all aspects of nuclear science and engineering can counter efficiently the pseudo-science and socio-political manipulation which has severely restricted nuclear energy development over the past three decades. National laboratories alone find this task extremely difficult, if not impossible

Experimental study of the burned of nuclear fuel by the gamma spectroscopy method

International Nuclear Information System (INIS)

Amador V, P.

2009-01-01

Accurate information on nuclear fuel burnup is of vital importance in reactor operation, fuel management and fuel-characteristics studies. Conventionally fuel management of the TRIGA III Reactor from the National Institute of Nuclear Research (ININ) is done through the thermal balance method (management) of the power generated during reactor operation, since it is known that with 1.24 grams of 235 U is possible to generate a power or 1 MW per day during the reactor operation. On the other hand, it is possible to calculate the operation time in days during a power of 1 MW with the help of the data registered in logs. With the information just mentioned one can calculate the quantity of 235 U consumed in the fuel during a complete period of irradiation. In order to compare and prove that the burnup values, calculated through the thermal balance method, are correct, the ININ implemented, for the first time, the gamma-ray spectroscopy method as an experimental technique to calculate the burnup of several fuel elements. Gamma-ray spectroscopy is a nondestructive method, so that the integrity of the fuel element is not affected which is of great importance. Since there is a direct relation between the activity of 137 Cs contained in the fuel elements and a series of constants which are unique for the radioisotope and for the high resolution system, the problem just simplifies in measuring the 137 Cs activities. Furthermore the 137 Cs concentration equation was developed theoretically and I wrote a computer program (AMAVAL) in Fortran. The task of this program is to calculate the concentrations and the activity through the use of the equation just mentioned and the history of each fuel element. The purpose of this is to compare and validate the experimental activities with the theoretical ones for each fuel element. (Author)

Volume reduction technology development for solid wastes from the nuclear fuel cycle

International Nuclear Information System (INIS)

Oh, Won Zin; Lee, Kune Woo; Song, Kee Chan; Choi, Wang Kyu; Kim, Young Min

1998-07-01

A great deal of solid wastes, which have various physical, chemical, and radiological characteristics, are generated from the nuclear fuel cycle facility as well as radioactive gaseous and liquid wastes. The treatment of the large quantity of solid wastes from the nuclear fuel cycle have great technical, economical and social effects on the domestic policy decision on the nuclear fuel cycle, such as operation and maintenance of the facility, waste disposal, etc. Cement immobilization, super compaction, and electrochemical dissolution were selected as the volume reduction technologies for solid wastes, which will generated from the domestic nuclear fuel cycle facility in the future. And the assessment of annual arisings and the preliminary conceptual design of volume reduction processes were followed. Electrochemical decontamination of α-radionuclides from the spent fuel hulls were experimentally investigated, and showed the successful results. However, β/γ radioactivity did not reduce to the level below which hulls can be classified as the low-level radioactive waste and sent to the disposal site for the shallow land burial. The effects of the various process variables in the electrochemical decontamination were experimentally analysed on the process. (author). 32 refs., 32 tabs., 52 figs

Pre-equilibrium emission and nuclear level densities in neutron induced reactions on Fe, Cr and Ni isotopes

International Nuclear Information System (INIS)

Ivascu, M.; Avrigeanu, M.; Ivascu, I.; Avrigeanu, V.

1989-01-01

The experimentally well known (n,p), (n,α) and (n,2n) reaction excitation functions, from threshold to 20 MeV incident energy, and neutron, proton and alpha-particle emission spectra at 14.8 MeV from Fe, Cr and Ni isotopes are calculated in the frame of a generalized Geometry-Dependent-Hybrid pre-equilibrium emission model, including angular momentum and parity conservation and alpha-particle emission, and the Hauser-Feshbach statistical model. Use of a consistent statistical model parameter set enables the validation of the pre-equilibrium emission model. Moreover, an enhanced pre-equilibrium emission from higher spin composite system states, associated with higher incident orbital momenta, has been evidenced. Higher orbital momenta involved also in the emergent channels of this process are suggested by calculations of the residual nuclei level populations. Finally, the unitary account of the (n, p) and (n, 2n) reaction excitation functions for Fe, Cr and Ni isotopes has allowed the proper establishment of the limits of the transition excitation range between the two different nuclear level density models used at medium and higher excitation energies, respectively. (author). 83 refs, 15 figs

Nuclear orientation experiments concerning odd-A gold isotopes

International Nuclear Information System (INIS)

Ligthart, H.J.

1982-01-01

This thesis describes nuclear spectroscopy aspects of nuclear orientation in the odd-A gold isotopes 191 Au, 193 Au, 195 Au and 197 Au. These isotopes lie in a transitional region between the spherical nuclei in the lead region and the strongly deformed rare earth isotopes. Following a general introduction to nuclear orientation, the experimental arrangement is described. A new technique is presented that applies in-beam recoil implantation inside the refrigerator itself and this was applied to the case of 191 Au. The three other gold isotopes were oriented using a conventional dilution refrigerator. The nuclear orientation experiments concerning 11/2 - isomers of the isotopes are described. The long-lived isomeric states were oriented using the large hyperfine field of gold in iron. Higher lying levels were studied by nuclear orientation of the Hg parent states. (Auth./C.F.)

Comparisons of experimental beta-ray spectra important to decay heat predictions with ENSDF [Evaluated Nuclear Structure Data File] evaluations

International Nuclear Information System (INIS)

Dickens, J.K.

1990-03-01

Graphical comparisons of recently obtained experimental beta-ray spectra with predicted beta-ray spectra based on the Evaluated Nuclear Structure Data File are exhibited for 77 fission products having masses 79--99 and 130--146 and lifetimes between 0.17 and 23650 sec. The comparisons range from very poor to excellent. For beta decay of 47 nuclides, estimates are made of ground-state transition intensities. For 14 cases the value in ENSDF gives results in very good agreement with the experimental data. 12 refs., 77 figs., 1 tab

Shocks from high-energy nuclear-interacting particles in the mountain Chakaltajya

Energy Technology Data Exchange (ETDEWEB)

Kamata, K [Tokyo Univ. (Japan)

1975-06-01

Experimental investigations of extensive air showers at the height of 5200 m above the sea level have been performed. The behaviour of high energy nuclear active particles in the cores of the showers has been studied using the nuclear knock-on method. The cross section of the proton inelastic interaction with the air is shown to increase with energy in the energy range of 3-9 TeV.

The mechanisms of the hadron-nucleus collision processes and of the hadron-nucleus collision induced nuclear reactions - in the light of experimental data

International Nuclear Information System (INIS)

Strugalski, Z.; Strugalska-Gola, E.

1997-01-01

The mechanisms of the hadron-nucleus collision processes and of the hadron-nucleus collision induced nuclear reactions are described - as experimentally based. The target nuclei are damaged definitely and locally in the collisions and the configurations of the nucleons in them became instable. The configuration must transit into stable stages of the nuclear transition reaction products. The difference between the initial internal energy of the unstable residual nucleus and the total final energy of the stable products of the nuclear transition reaction may be released in some cases

Numerical and experimental analysis of the impact of a nuclear spent fuel cask

Energy Technology Data Exchange (ETDEWEB)

Aquaro, D. [Department of Mechanical, Nuclear and Production Engineering (DIMNP), Pisa University, Via Diotisalvi, Pisa (Italy); Zaccari, N., E-mail: nicola.zaccari@enel.i [Department of Mechanical, Nuclear and Production Engineering (DIMNP), Pisa University, Via Diotisalvi, Pisa (Italy); Di Prinzio, M.; Forasassi, G. [Department of Mechanical, Nuclear and Production Engineering (DIMNP), Pisa University, Via Diotisalvi, Pisa (Italy)

2010-04-15

This paper deals with the numerical and experimental analyses of a shell type shock absorber for a nuclear spent fuel cask. Nine-meter free drop tests performed on reduced scale models are described. The results are compared with numerical simulations performed with FEM computer codes, considering reduced scale models as well as the prototype. The paper shows the results of a similitude analysis, with which the data obtained by means of the reduced scale models can be extrapolated to the prototype. Small discrepancies were obtained using large-scale models (1:2 and 1:6), while small-scale models (1:12) did not give reliable results. A 1:9 scale model provided useful information with a less than 20% error.

Radiological safety for the public during nuclear emergencies: application of intervention levels and derived intervention levels

International Nuclear Information System (INIS)

Thomas, G.; Kumar, K.S.

2006-01-01

Control of radiation exposures to the public following a major nuclear accident can be achieved through intervention by implementing countermeasures such as sheltering, iodine prophylaxis, evacuation, control of foodstuff, etc. Intervention levels (I.L.) are formulated such that exposure to individuals from all exposure pathways is well below the thresholds for deterministic effects, and risk of stochastic health effects to individuals and overall incidence of stochastic effects in the exposed population are minimized. It is also necessary to translate such I.L. into quantities, called derived intervention levels (D.I.L.) that can be measured. The I.L. followed in various countries for the recommended countermeasures cater to the exposure range of 1-50 mSv for sheltering, 10-500 mSv for evacuation, 30- 1000 mSv for iodine prophylaxis and 1-10 mSv for food control. The models used for these are based on conservative estimations assuming maximum dose delivered to the critical group for the pathway assumed. While the concept of upper dose level above which countermeasures is always justified to avoid deterministic effects, the lower range of dose levels have to be optimised based on various parameters as discussed in this paper. While arriving at the I.L., the question to be addressed is: How much (dose) risk should be averted by the intervention planned? Implementation of any countermeasure will result in some inconvenience/ limitation of resource/ disruption and consequently, a positive net benefit will justify the intervention. Sheltering may result in substantially less disruption than evacuation, but if the type of sheltering is not offering enough radiation shielding or ventilation protection, this may not result in significant reduction of exposure. It is to be ensured that deterministic effects are totally avoided and it is possible to define a safe threshold exposure and above which balancing risks and benefits is not applicable. While the dose limit for the

Non-destructive analysis of spent nuclear fuel

International Nuclear Information System (INIS)

Popovic, D.

1961-12-01

Nondestructive analysis of fuel elements dealt with determining the isotope contents which provide information about the burnup level, quantities of fission products and neutron-multiplication properties of the irradiated fuel. Methods for determination of the isotope ratio of the spent fuel are both numerical and experimental. This report deals with the experimental method. This means development of the experimental methods for direct measurement of the isotope content. A number of procedures are described: measurements of α, β and γ activities of the isotopes; measurement of secondary effects of nuclear reactions with thermal neutrons and fast neutrons; measurement of cross sections; detection of prompt and delayed neutrons

Extension of the energy range of the experimental activation cross-sections data of longer-lived products of proton induced nuclear reactions on dysprosium up to 65MeV.

Science.gov (United States)

Tárkányi, F; Ditrói, F; Takács, S; Hermanne, A; Ignatyuk, A V

2015-04-01

Activation cross-sections data of longer-lived products of proton induced nuclear reactions on dysprosium were extended up to 65MeV by using stacked foil irradiation and gamma spectrometry experimental methods. Experimental cross-sections data for the formation of the radionuclides (159)Dy, (157)Dy, (155)Dy, (161)Tb, (160)Tb, (156)Tb, (155)Tb, (154m2)Tb, (154m1)Tb, (154g)Tb, (153)Tb, (152)Tb and (151)Tb are reported in the 36-65MeV energy range, and compared with an old dataset from 1964. The experimental data were also compared with the results of cross section calculations of the ALICE and EMPIRE nuclear model codes and of the TALYS nuclear reaction model code as listed in the latest on-line libraries TENDL 2013. Copyright © 2015. Published by Elsevier Ltd.

The OEEC European Nuclear Energy Agency

International Nuclear Information System (INIS)

1961-01-01

The European Nuclear Energy Agency (ENEA) was set up in December 1957 as part of the OEEC to develop nuclear collaboration in Western Europe. The promotion of joint undertakings is one of the most important functions of ENEA, and why one of the first committees of the Agency to be set up was its Top Level Group on Co-operation in the Reactor Field. International collaboration in joint undertakings enables resources in effort, equipment and money to be pooled for the maximum benefit of the countries participating, and is the only way whereby a sufficiently wide range of research possibilities can be covered in a reasonable time. Examples fro such projects are: 1) Halden project - a joint three-year project to exploit the boiling heavy water reactor built by the Norwegian Institute for Atom energy at Halden; 2) Dragon Project - to investigate the possibilities of high-temperature gas-cooled reactors centered on the construction and operation, by an international team, of an experimental 20 MWt high-temperature gas-cooled reactor (Dragon) at the UK Atomic Energy Establishment at Winfrith; 3) Eurochemic - with a principle objective to construct an experimental plant for the treatment of used uranium fuel from reactors in the participating countries; 4) Nuclear Shops. In addition to promoting joint undertakings, a function of ENEA is to encourage scientific and technical collaboration between national research organizations. Co-operation has been facilitated in the areas od nuclear data, food irradiation, environment radioactivity, training, information and nuclear legislation

The OEEC European Nuclear Energy Agency

Energy Technology Data Exchange (ETDEWEB)

NONE

1961-07-15

The European Nuclear Energy Agency (ENEA) was set up in December 1957 as part of the OEEC to develop nuclear collaboration in Western Europe. The promotion of joint undertakings is one of the most important functions of ENEA, and why one of the first committees of the Agency to be set up was its Top Level Group on Co-operation in the Reactor Field. International collaboration in joint undertakings enables resources in effort, equipment and money to be pooled for the maximum benefit of the countries participating, and is the only way whereby a sufficiently wide range of research possibilities can be covered in a reasonable time. Examples fro such projects are: 1) Halden project - a joint three-year project to exploit the boiling heavy water reactor built by the Norwegian Institute for Atom energy at Halden; 2) Dragon Project - to investigate the possibilities of high-temperature gas-cooled reactors centered on the construction and operation, by an international team, of an experimental 20 MWt high-temperature gas-cooled reactor (Dragon) at the UK Atomic Energy Establishment at Winfrith; 3) Eurochemic - with a principle objective to construct an experimental plant for the treatment of used uranium fuel from reactors in the participating countries; 4) Nuclear Shops. In addition to promoting joint undertakings, a function of ENEA is to encourage scientific and technical collaboration between national research organizations. Co-operation has been facilitated in the areas od nuclear data, food irradiation, environment radioactivity, training, information and nuclear legislation.

Methodology for determining acceptable residual radioactive contamination levels at decommissioned nuclear facilities/sites

International Nuclear Information System (INIS)

Watson, E.C.; Kennedy, W.E. Jr.; Hoenes, G.R.; Waite, D.A.

1979-01-01

The ultimate disposition of decommissioned nuclear facilities and their surrrounding sites depends upon the degree and type of residual contamination. Examination of existing guidelines and regulations has led to the conclusion that there is a need for a general method to derive residual radioactive contamination levels that are acceptable for public use of any decommissioned nuclear facility or site. This paper describes a methodology for determining acceptable residual radioactive contamination levels based on the concept of limiting the annual dose to members of the public. It is not the purpose of this paper to recommend or even propose dose limits for the exposure of the public to residual radioactive contamination left at decommissioned nuclear facilities or sites. Unrestricted release of facilities and/or land is based on the premise that the potential annual dose to any member of the public using this property from all possible exposure pathways will not exceed appropriate limits as may be defined by Federal regulatory agencies. For decommissioned land areas, consideration should be given to people living directly on previously contaminated areas, growing crops, grazing food animals and using well water. Mixtures of radionuclides in the residual contamination representative of fuel reprocessing plants, light water reactors and their respective sites are presented. These mixtures are then used to demonstrate the methodology. Example acceptable residual radioactive contamination levels, based on an assumed maximum annual dose of one millirem, are calculated for several selected times following shutdown of a facility. It is concluded that the methodology presented in this paper results in defensible acceptable residual contamination levels that are directly relatable to risk assessment with the proviso that an acceptable limit to the maximum annual dose will be established. (author)

Statistical methods in nuclear theory

International Nuclear Information System (INIS)

Shubin, Yu.N.

1974-01-01

The paper outlines statistical methods which are widely used for describing properties of excited states of nuclei and nuclear reactions. It discusses physical assumptions lying at the basis of known distributions between levels (Wigner, Poisson distributions) and of widths of highly excited states (Porter-Thomas distribution, as well as assumptions used in the statistical theory of nuclear reactions and in the fluctuation analysis. The author considers the random matrix method, which consists in replacing the matrix elements of a residual interaction by random variables with a simple statistical distribution. Experimental data are compared with results of calculations using the statistical model. The superfluid nucleus model is considered with regard to superconducting-type pair correlations

Evaluations of average level spacings

International Nuclear Information System (INIS)

Liou, H.I.

1980-01-01

The average level spacing for highly excited nuclei is a key parameter in cross section formulas based on statistical nuclear models, and also plays an important role in determining many physics quantities. Various methods to evaluate average level spacings are reviewed. Because of the finite experimental resolution, to detect a complete sequence of levels without mixing other parities is extremely difficult, if not totally impossible. Most methods derive the average level spacings by applying a fit, with different degrees of generality, to the truncated Porter-Thomas distribution for reduced neutron widths. A method that tests both distributions of level widths and positions is discussed extensivey with an example of 168 Er data. 19 figures, 2 tables

Experimental verification of the imposing principle for maximum permissible levels of multicolor laser radiation

Directory of Open Access Journals (Sweden)

Ivashin V.A.

2013-12-01

Full Text Available Aims. The study presents the results of experimental research to verify the principle overlay for maximum permissible levels (MPL of multicolor laser radiation single exposure on eyes. This principle of the independence of the effects of radiation with each wavelength (the imposing principle, was founded and generalized to a wide range of exposure conditions. Experimental verification of this approach in relation to the impact of laser radiation on tissue fundus of an eye, as shows the analysis of the literature was not carried out. Material and methods. Was used in the experimental laser generating radiation with wavelengths: Л1 =0,532 microns, A2=0,556to 0,562 microns and A3=0,619to 0,621 urn. Experiments were carried out on eyes of rabbits with evenly pigmented eye bottom. Results. At comparison of results of processing of the experimental data with the calculated data it is shown that these levels are close by their parameters. Conclusions. For the first time in the Russian Federation had been performed experimental studies on the validity of multi-colored laser radiation on the organ of vision. In view of the objective coincidence of the experimental data with the calculated data, we can conclude that the mathematical formulas work.

The Fourier transform as a signature for chaos in nuclear energy levels

International Nuclear Information System (INIS)

Bybee, C.R.; Mitchell, G.E.; Shriner, J.F. Jr.

1996-01-01

The Fourier transform of the autocorrelation function is an alternative test to characterize level statistics. For GOE statistics there is a suppression of the Fourier transform near the origin; this correlation hole is absent for Poisson statistics. Numerical modeling has been used to quantify the method and determine the dependence of the correlation-hole area on number, density, sampling interval, and fraction of missing or spurious levels. For large N the normalized correlation-hole area is a nearly universal constant and insensitive to missing and spurious levels. However, for the smaller sample sizes typical of nuclear data, application of the FT method yields ambiguous results. (orig.)

The Fourier transform as a signature for chaos in nuclear energy levels

Energy Technology Data Exchange (ETDEWEB)

Bybee, C.R. [North Carolina State Univ., Raleigh, NC (United States)]|[Triangle Universities Nuclear Lab., Durham, NC (United States); Mitchell, G.E. [North Carolina State Univ., Raleigh, NC (United States)]|[Triangle Universities Nuclear Lab., Durham, NC (United States); Shriner, J.F. Jr. [Tennessee Technological Univ., Cookeville (United States)

1996-08-01

The Fourier transform of the autocorrelation function is an alternative test to characterize level statistics. For GOE statistics there is a suppression of the Fourier transform near the origin; this correlation hole is absent for Poisson statistics. Numerical modeling has been used to quantify the method and determine the dependence of the correlation-hole area on number, density, sampling interval, and fraction of missing or spurious levels. For large N the normalized correlation-hole area is a nearly universal constant and insensitive to missing and spurious levels. However, for the smaller sample sizes typical of nuclear data, application of the FT method yields ambiguous results. (orig.)

Low-level radioactive waste management in EDF nuclear power plants (FRANCE)

International Nuclear Information System (INIS)

Boussard, C.

1991-01-01

This paper shows some recent examples of Low-level radioactive waste management in EDF nuclear power plants: - Radioactive liquid wastes proceeding from steam generators leaching (NOGENT SUR SEINE-1 REACTOR) - Thermal insulation proceeding from heat exchanger and blower (CHINON-2 REACTOR) - Old iron from reactor dismantling (CHINON-3 REACTOR, MARCOULE G1 REACTOR, MARCOULE G2-G3 REACTORS) - fresh air filter and fire detector - CHINON-2 REACTOR breaker chambers

Determining of the nuclear composition of primary cosmic rays from the experimental distributions of multiple muons in atmospheric showers

International Nuclear Information System (INIS)

Beshtoev, Kh.M.

1993-01-01

Various approaches are discussed for determining the nuclear composition of the primary cosmic radiation from the distributions of multiple muons. Results are presented of calculations of the distributions of multiple muons for A 1 , A 4 , A 14 , A 26 , A 56 nuclei for an infinite plane and for the underground scintillation telescope of the Institute for Nuclear Research of the Academy of Sciences of Russia.The most suitable technique for determination of the primary nuclear composition of cosmic rays from the distribution of multiple muons is shown to be the approximate solution of a set of N equations, in which the respective coefficients of the contributions of various nuclei A i (i=1-N) to the primary composition serve as variables, while the remaining parts of these equations are the distributions of multiple muons obtained experimentally. 7 refs.; 2 tabs

Regulatory overview report 2014 concerning nuclear safety in Swiss nuclear installations

International Nuclear Information System (INIS)

2015-06-01

transport/storage casks with spent fuel assemblies and vitrified residue packages as well as six casks with decommissioned waste from the experimental nuclear power plant at Lucens. During the year, ZWILAG conducted one campaign to incinerate and melt radioactive waste; no reportable event was recorded. The nuclear facilities at PSI consist in the hot laboratory, the nuclear facilities being decommissioned (the three former research reactors SAPHIR, DIORIT and PROTEUS together with the experimental incineration plant that was taken out of service in 2002) and the facilities for the disposal of radioactive materials. During 2014, there were no reportable events at PSI. There was one reportable event at the research reactor of the UniB and one reportable event at the research reactor of the EPFL. ENSI concluded that the nuclear facilities at PSI and the research reactors at Lausanne and Basel had complied with their approved operating conditions. The amount of radioactive material released into the environment via waste water and exhaust air from all nuclear power facilities was significantly less than the limits specified in the operating licenses. The maximum dose for persons in the immediate vicinity of a plant was less than 1 % of the annual exposure to natural radiation. Spent fuel assemblies from Swiss nuclear power plants from previous years are being reprocessed at the reprocessing facilities at La Hague (France) and Sellafield (United Kingdom). The waste produced during reprocessing must be returned to Switzerland. During 2014, consignments containing high-level and medium-level waste were transported from La Hague to ZWILAG. The three-stage procedure for site selection for deep geological repositories is currently in Stage 2. During 2014, ENSI concluded its review of the geological state of knowledge for which the National Cooperative for the Disposal of Radioactive Waste (Nagra) had been requested to undertake 41 additional investigations. Nagra will now conduct

Statistical nuclear properties and synthesis of 138La

Directory of Open Access Journals (Sweden)

Kheswa B. V.

2015-01-01

Full Text Available The synthesis of the neutron deficient 138La nucleus has been a puzzle for a long time. It has not been clear whether it is produced through photodisintegration processes or neutrino induced reactions due to unavailability of experimental data for nuclear level densities and γ strength functions of 138,139La nuclei. In the present work these nuclear properties have been measured and are used to investigate the synthesis of 138La. The results support the neutrino interactions as a dominant production process for 138La.

Experimental investigation of channel avulsion frequency on river deltas under rising sea levels

Science.gov (United States)

Silvestre, J.; Chadwick, A. J.; Steele, S.; Lamb, M. P.

2017-12-01

River deltas are low-relief landscapes that are socioeconomically important; they are home to over half a billion people worldwide. Many deltas are built by cycles of lobe growth punctuated by abrupt channel shifts, or avulsions, which often reoccur at a similar location and with a regular frequency. Previous experimental work has investigated the effect of hydrodynamic backwater in controlling channel avulsion location and timing on deltas under constant sea level conditions, but it is unclear how sea-level rise impacts avulsion dynamics. We present results from a flume experiment designed to isolate the role of relative sea-level rise on the evolution of a backwater-influenced delta. The experiment was conducted in the river-ocean facility at Caltech, where a 7m long, 14cm wide alluvial river drains into a 6m by 3m "ocean" basin. The experimental delta grew under subcritical flow, a persistent backwater zone, and a range of sea level rise rates. Without sea level rise, lobe progradation produced in-channel aggradation and periodic avulsions every 3.6 ± 0.9 hours, which corresponded to when channels aggraded to approximately one-half of their flow depth. With a modest rate of sea-level rise (0.25 mm/hr), we observed enhanced aggradation in the backwater zone, causing channels to aggrade more quickly and avulse more frequently (every 2.1 ± 0.6 hours). In future work, we expect further increases in the rate of relative sea-level rise to cause avulsion frequency to decrease as the delta drowns and the backwater zone retreats upstream. Experimental results can serve as tests of numerical models that are needed for hazard mitigation and coastal sustainability efforts on drowning deltas.