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Sample records for nuclear independent particle

  1. 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.)

  2. Structure of single-particle nuclear densities from Hartree-Fock theory and model independent analysis

    International Nuclear Information System (INIS)

    Starodubskij, V.E.; Shaginyan, V.R.

    1979-01-01

    Friar-Negele method is applied to determine the static densities of neutrons and nuclear matter from the fast proton-nuclei elastic scattering data. This model-independent analysis (MIA) has been carried out for 28 Si, sup(32,34)S, sup(40,42,44,48)Ca, 48 Ti, sup(58,60)Ni, 90 Zr, 208 Pb nuclei. The binding energies, rms radii, densities and scattering cross sections of 1 GeV-proton are calculated in the framework of the Hartree-Fock theory (HF) with Skyrme's interaction. The HF and MIA densities and cross sections have been compared to draw a conclusion on the quality of the HF densities. Calculation of the cross sections has included the spin-orbit interaction with parameters taken from the polarization data

  3. Particle-nuclear intersections

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    With the traditional distinctions between particle and nuclear physics becoming increasing blurred, the Fifth Conference on the Intersections of Particle and Nuclear Physics, held from May 31 to June 6 in St. Petersburg, Florida, brought together particle and nuclear physicists to discuss common research efforts and to define and plan a united approach

  4. Nuclear energy and independence

    International Nuclear Information System (INIS)

    Rotblat, J.

    1978-01-01

    The pro-nuclear lobby in the United Kingdom won its battle. The Report on the Windscale Inquiry strongly endorsed the application by British Nuclear Fuels (a company owned by the government) to set up a plant to reprocess spent oxide fuels from thermal reactors; a motion in Parliament to postpone a decision was heavily defeated. The Windscale Inquiry was an attempt to settle in a civilized manner what has been tried in other countries by demonstrations and violence. In this exercise, a High Court Judge was given the task of assessing an enormous mass of highly complex technical and medical material, as well as economic, social, and political arguments. The outcome is bitterly disappointing to the objectors, all of whose arguments were rejected. Although the question of whether Britain should embark on a fast breeder reactor program was specifically excluded from the Inquiry, it clearly had a bearing on it. A decision not to proceed with the reprocessing plant would have made a fast breeder program impossible; indeed, the Report argues that such a decision would involve throwing away large indigenous energy resources, a manifest advocacy of the fast breeder. Other arguments for the decision to go ahead with the reprocessing plant included the need to keep the nuclear industry alive, and the profit which Britain will make in processing fuels from other countries, particularly Japan. The author comments further on present UK policy, taking a dissenting view, and then comments on the paper, Nuclear Energy and the Freedom of the West, by A.D. Sakharov

  5. Comment on atomic independent-particle models

    International Nuclear Information System (INIS)

    Doda, D.D.; Gravey, R.H.; Green, A.E.S.

    1975-01-01

    The Hartree-Fock-Slater (HFS) independent-particle model in the form developed by Hermann and Skillman (HS) and the Green, Sellin, and Zachor (GSZ) analytic independent-particle model are being used for many types of applications of atomic theory to avoid cumbersome, albeit more rigorous, many-body calculations. The single-electron eigenvalues obtained with these models are examined and it is found that the GSZ model is capable of yielding energy eigenvalues for valence electrons which are substantially closer to experimental values than are the results of HS-HFS calculations. With the aid of an analytic representation of the equivalent HS-HFS screening function, the difficulty with this model is identified as a weakness of the potential in the neighborhood of the valence shell. Accurate representations of valence states are important in most atomic applications of the independent-particle model

  6. Particle and nuclear physics

    International Nuclear Information System (INIS)

    Ning, H.; Chong-shi, W.

    1986-01-01

    This book contains the proceedings of the September symposium. There are two parts to this book divided according to particle physics and nuclear physics. Some of the titles of the papers are as follows: Bifurcation and Dynamical Symmetry Breaking, Negative Binomial Distribution for the Multiplicity Distributions in e/sup +/e/sup -/ Annihilation, Variational Study of Lattice QCD, Rescaling for Kaon Structure Function, SDG Boson Model and its Application, The Pair-Aligned Intrinsic Wave Function in Single-j Configuration, and The Short Range Effective Interaction and the Spectra of Calcium Isotopes in (f-p) Space

  7. Independent particle Schroedinger Fluid: moments of inertia

    International Nuclear Information System (INIS)

    Kan, K.K.; Griffin, J.J.

    1977-10-01

    This philosophy of the Single Particle Schroedinger Fluid, especially as regards the velocity fields which find such a natural role therein, is applied to the study of the moments of inertia of independent Fermion system. It is shown that three simplified systems exhibit the rigid-body rotational velocity field in the limit of large A, and that the leading deviations, both on the average and fluctuating, from this large A limit can be described analytically, and verified numerically. For a single particle in a Hill-Wheeler box the moments are studied numerically, and their large fluctuations identified with the specific energy level degeneracies of its parallelepiped shape. The full assemblage of these new and old results is addressed to the question of the necessary and sufficient condition that the moment have the rigid value. Counterexamples are utilized to reject some conditions, and the conjecture is argued that Unconstrained Shape Equilibrium might be the necessary and sufficient condition. The spheroidal square well problem is identified as a promising test case

  8. Nuclear and particle physics 1993

    International Nuclear Information System (INIS)

    MacGregor, I.J.D.; Doyle, A.T.

    1993-01-01

    This item documents the International Conference on Nuclear and Particle Physics held at the University of Glasgow, UK, from 30th March to 1st April 1993. It was organised by the Department of Physics and Astronomy at Glasgow University on behalf of the Nuclear and Particle Physics Division of the Institute of Physics. The scientific programme covered many areas of current interest in nuclear and particle physics. Particle physics topics included up to the minute reports on the physics currently coming from CERN'S Low Energy Antiproton Ring (LEAR), Hadron-Elektron-Ring Analage (HERA) and Large Electron-Positron Storage Rings (LEP), and reviews of quantum chromodynamics (QCD) lattice gauge theory. Looking to the future the programme covered the search for the Higgs boson and a review of physics experiments planned for the new generation of accelerators at Large Hadron Collider (LHC) and Superconducting Supercollider (SSC). The conference coincided with the final closure of the world class Nuclear Structure Facility at Daresbury and marked the transition of United Kingdom (UK) nuclear physics research into a new era of international collaboration. Several talks described new international collaborative research programmes in nuclear physics initiated by UK scientists. The conference also heard of new areas of nuclear physics which will in future be opened up by high energy continuous beam electron accelerators and by radioactive ion beam accelerators. (author)

  9. Model-independent particle accelerator tuning

    Directory of Open Access Journals (Sweden)

    Alexander Scheinker

    2013-10-01

    Full Text Available We present a new model-independent dynamic feedback technique, rotation rate tuning, for automatically and simultaneously tuning coupled components of uncertain, complex systems. The main advantages of the method are: (1 it has the ability to handle unknown, time-varying systems, (2 it gives known bounds on parameter update rates, (3 we give an analytic proof of its convergence and its stability, and (4 it has a simple digital implementation through a control system such as the experimental physics and industrial control system (EPICS. Because this technique is model independent it may be useful as a real-time, in-hardware, feedback-based optimization scheme for uncertain and time-varying systems. In particular, it is robust enough to handle uncertainty due to coupling, thermal cycling, misalignments, and manufacturing imperfections. As a result, it may be used as a fine-tuning supplement for existing accelerator tuning/control schemes. We present multiparticle simulation results demonstrating the scheme’s ability to simultaneously adaptively adjust the set points of 22 quadrupole magnets and two rf buncher cavities in the Los Alamos Neutron Science Center (LANSCE Linear Accelerator’s transport region, while the beam properties and rf phase shift are continuously varying. The tuning is based only on beam current readings, without knowledge of particle dynamics. We also present an outline of how to implement this general scheme in software for optimization, and in hardware for feedback-based control/tuning, for a wide range of systems.

  10. Particle physics using nuclear targets

    International Nuclear Information System (INIS)

    Ferbel, T.

    1978-01-01

    The use of nuclear targets in particle physics is discussed and some recent results obtained in studies of hadronic interactions on nuclei summarized. In particular experimental findings on inclusive production and on coherent dissociation of mesons and baryons at high energies are presented. 41 references

  11. 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...

  12. Nuclear physics with polarized particles

    CERN Document Server

    Paetz gen Schieck, Hans

    2012-01-01

    The measurement of spin-polarization observables in reactions of nuclei and particles is of great utility and advantage when the effects of single-spin sub-states are to be investigated. Indeed, the unpolarized differential cross-section encompasses the averaging over the spin states of the particles, and thus loses details of the interaction process. This introductory text combines, in a single volume, course-based lecture notes on spin physics and on polarized-ion sources with the aim of providing a concise yet self-contained starting point for newcomers to the field, as well as for lecturers in search of suitable material for their courses and seminars. A significant part of the book is devoted to introducing the formal theory-a description of polarization and of nuclear reactions with polarized particles. The remainder of the text describes the physical basis of methods and devices necessary to perform experiments with polarized particles and to measure polarization and polarization effects in nuclear rea...

  13. Independent assessment for new nuclear reactor safety

    Directory of Open Access Journals (Sweden)

    D'Auria Francesco

    2017-01-01

    Full Text Available A rigorous framework for safety assessment is established in all countries where nuclear technology is used for the production of electricity. On the one side, industry, i.e. reactor designers, vendors and utilities perform safety analysis and demonstrate consistency between results of safety analyses and requirements. On the other side, regulatory authorities perform independent assessment of safety and confirm the acceptability of safety of individual reactor units. The process of comparing results from analyses by reactor utilities and regulators is very complex. The process is also highly dependent upon mandatory approaches pursued for the analysis and from very many details which required the knowledge of sensitive proprietary data (e.g. spacer designs. Furthermore, all data available for the design, construction and operation of reactors produced by the nuclear industry are available to regulators. Two areas for improving the process of safety assessment for individual Nuclear Power Plant Units are identified: New details introduced by industry are not always and systematically requested by regulators for the independent assessment; New analytical techniques and capabilities are not necessarily used in the analyses by regulators (and by the industry. The established concept of independent assessment constitutes the way for improving the process of safety assessment. This is possible, or is largely facilitated, by the recent availability of the so-called Best Estimate Plus Uncertainty approach.

  14. Independent assessment for new nuclear reactor safety

    International Nuclear Information System (INIS)

    D'Auria, F.; Glaeser, H.; Debrecin, N.

    2017-01-01

    A rigorous framework for safety assessment is established in all countries where nuclear technology is used for the production of electricity. On one side, industry, i.e. reactor designers, vendors and utilities perform safety analysis and demonstrate consistency between results of safety analyses and requirements. On the other side, regulatory authorities perform independent assessment of safety and confirm the acceptability of safety of individual reactor units. The process of comparing results from analyses by reactor utilities and regulators is very complex. The process is also highly dependent upon mandatory approaches pursued for the analysis and from very many details which required the knowledge of sensitive proprietary data (e.g. spacer designs). Furthermore, all data available for the design, construction and operation of reactors produced by the nuclear industry are available to regulators. Two areas for improving the process of safety assessment for individual Nuclear Power Plant Units are identified: New details introduced by industry are not always and systematically requested by regulators for the independent assessment; New analytical techniques and capabilities are not necessarily used in the analyses by regulators (and by the industry). The established concept of independent assessment constitutes the way for improving the process of safety assessment. This is possible, or is largely facilitated, by the recent availability of the so-called Best Estimate Plus Uncertainty (BEPU) approach. (authors)

  15. 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.)

  16. Nuclear physics with strange particles

    International Nuclear Information System (INIS)

    Dover, C.B.

    1988-01-01

    Recent progress in the understanding of strange particle interactions with nuclear systems is reviewed. We discuss the relative merits of various reactions such as (K - , π/sup +-/), (π + , K + ), or (γ, K + ) for hypernuclear production. The structure of /sub Λ/ 13 C is analyzed in some detail, in order to illustrate the role of the ΛN residual interaction and approximate dynamical symmetries in hypernuclear structure. Recent results on the single particle states of a Λ in heavy systems, as revealed by (π + , K + ) reaction studies, are used to extract information on the density dependence and effective mass which characterize the Λ-nucleus mean field. Finally, we develop the idea the K + -nucleus scattering at low energies is sensitive to the subtle ''swelling'' effects for nucleons bound in nuclei. 64 refs., 13 figs

  17. Nuclear thermodynamics below particle threshold

    International Nuclear Information System (INIS)

    Schiller, A.; Agvaanluvsan, U.; Algin, E.; Bagheri, A.; Chankova, R.; Guttormsen, M.; Hjorth-Jensen, M.; Rekstad, J.; Siem, S.; Sunde, A. C.; Voinov, A.

    2005-01-01

    From a starting point of experimentally measured nuclear level densities, we discuss thermodynamical properties of nuclei below the particle emission threshold. Since nuclei are essentially mesoscopic systems, a straightforward generalization of macroscopic ensemble theory often yields unphysical results. A careful critique of traditional thermodynamical concepts reveals problems commonly encountered in mesoscopic systems. One of which is the fact that microcanonical and canonical ensemble theory yield different results, another concerns the introduction of temperature for small, closed systems. Finally, the concept of phase transitions is investigated for mesoscopic systems

  18. The nuclear single particle model

    International Nuclear Information System (INIS)

    Mang, H.

    1985-01-01

    Twenty years ago in December 1963 one half of the Nobel prize in Physics was awarded to Maria Goeppert-Mayer and Johannes Daniel Jensen for their work on the nuclear shell model. They suggested independently that a strong spin-orbit force with the opposite sign of the one known from atomic physics should be added to the shell-model potential. This proved to be the crucial new idea, because then all the bits of and pieces of evidence that had accumulated over the years fell into place. The author begins with the basic assumption: In a nucleus nucleons move almost independently of each other in an average or shell-model potential. He then provides experimental evidence plausibility arguments and mathematical deductions

  19. A comparative study of independent particle model based ...

    Indian Academy of Sciences (India)

    We find that among these three independent particle model based methods, the ss-VSCF method provides most accurate results in the thermal averages followed by t-SCF and the v-VSCF is the least accurate. However, the ss-VSCF is found to be computationally very expensive for the large molecules. The t-SCF gives ...

  20. Nuclear Safety Authority independence, progresses to be considered

    International Nuclear Information System (INIS)

    Delzangles, Hubert

    2013-01-01

    The Nuclear Safety Authority is an independent administrative body. Nevertheless, functional and organic independence from operators and government can have different degrees. Having a look on the actual context, where government holds a large part of the main nuclear French operators, independence has to be maximal in order to avoid any conflict of interest that could attempt to nuclear safety. In a global point of view, it is possible to think about the risks or the benefits of the institutionalized cooperation between national regulators on the necessary independence of the Nuclear Safety Authority

  1. Nuclear data needs in nuclear astrophysics: Charged-particle reactions

    International Nuclear Information System (INIS)

    Smith, Michael S.

    2001-01-01

    Progress in understanding a diverse range of astrophysical phenomena - such as the Big Bang, the Sun, the evolution of stars, and stellar explosions - can be significantly aided by improved compilation, evaluation, and dissemination of charged-particle nuclear reaction data. A summary of the charged-particle reaction data needs in these and other astrophysical scenarios is presented, along with recommended future nuclear data projects. (author)

  2. Comparative studies of atomic independent-particle potentials

    International Nuclear Information System (INIS)

    Talman, J.D.; Ganas, P.S.; Green, A.E.S.

    1979-01-01

    A number of atomic properties are compared in various independent-particle models for atoms. The models studied are the Hartree-Fock method, a variationally optimized potential model, a parametrized analytic form of the same model, parametrized analytic models constructed to fit atomic energy levels, the so-called Hartree-Fock-Slater model, and the Xα model. The physical properties compared are single-particle energy levels, total energies, and dipole polarizabilities. The extent to which the virial theorem is satisfied in the different models is also considered. The atoms Be, Ne, Ar, Kr, and Xe and ions O v and Al iv hav been compared. The results show that the experimental properties can be well represented by several of the independent-particle models. Since it has been shown that the optimized potential models yield wavefunctions that are almost the same as Hartree-Fock wavefunctions, they provide a natural solution to the problem of extending the Hartree-Fock method to excited states

  3. Three-particle forces and nuclear models

    International Nuclear Information System (INIS)

    Krutov, V.A.

    1980-01-01

    Different nuclear models accounting and unaccounting for three-particle internucleon forces (TIF) are reviewed. At present only two nuclear models use manifestly TIP: the Vautherin-Brink-Skyrme (VBS) model and the model proposed by the author of the review and called the semiphenomenological (SP) nuclear model. There is a short discussion of major drawbacks of models unaccounting for TIF: multiparticle shell model, ''superfluid model'', Harty-Fock calculations with two-particle forces, Bruckner-Hartry-Fock calculations, the relativistic self-consistent nuclear model. The VBS and SP models are discussed in detail. It is concluded, that the employment of TIF even in a very simplified form (extremely short-range) puts away a lot of problems characteristic to models limited by two-particle forces (collapse at iteratious in Hartry-Fock, simultaneous fitting of the binding energy of a nucleus and the binding energy of a nucleon, etc.) and makes it possible to obtain in a rather simple way such nuclear characteristics as nuclear binding energy, nuclear mean square root radii, nucleon density of a nucleus

  4. Foundations of nuclear and particle physics

    CERN Document Server

    Donnelly, T William; Holstein, Barry R; Milner, Richard G; Surrow, Bernd

    2017-01-01

    This textbook brings together nuclear and particle physics, presenting a balanced overview of both fields as well as the interplay between the two. The theoretical as well as the experimental foundations are covered, providing students with a deep understanding of the subject. In-chapter exercises ranging from basic experimental to sophisticated theoretical questions provide an important tool for students to solidify their knowledge. Suitable for upper undergraduate courses in nuclear and particle physics as well as more advanced courses, the book includes road maps guiding instructors on tailoring the content to their course. Online resources including color figures, tables, and a solutions manual complete the teaching package. This textbook will be essential for students preparing for further study or a career in the field who require a solid grasp of both nuclear and particle physics.

  5. Nuclear and Particle Physics, Astrophysics and Cosmology : T-2 : LANL

    Science.gov (United States)

    linked in Search T-2, Nuclear and Particle Physics, Astrophysics and Cosmology T-2 Home T Division Focus Areas Nuclear Information Service Nuclear Physics Particle Physics Astrophysics Cosmology CONTACTS Group fundamental and applied theoretical research in applied and fundamental nuclear physics, particle physics

  6. Intersections between particle and nuclear physics

    International Nuclear Information System (INIS)

    Bunce, G.M.

    1988-01-01

    This report contains papers from an AIP conference on the intersections between particle and nuclear physics. Some of the general topics covered are: Accelerator physics; Antiproton physics; Electron and muon physics; Hadron scattering; Hadron spectroscopy; Meson and lepton decays; Neutrino physics; Nonaccelerator and astrophysics; Relativistic heavy-ion physics; and Spin physics. There are 166 papers that will be processed separately

  7. PSI nuclear and particle physics newsletter 1990

    International Nuclear Information System (INIS)

    Frosch, R.; Furrer, F.

    1991-01-01

    This newsletter contains reports on nuclear and particle physics supported by the F1 division of PSI. Groups were invited to present new preliminary or final results obtained in 1990. As ususal, the contributions were not referred. They should be quoted after consultation with the authors only. (author) figs., tabs., refs

  8. A Vision of Nuclear and Particle Physics

    Energy Technology Data Exchange (ETDEWEB)

    Montgomery, Hugh E. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2016-08-01

    This paper will consist of a selected, personal view of some of the issues associated with the intersections of nuclear and particle physics. As well as touching on the recent developments we will attempt to look at how those aspects of the subject might evolve over the next few years.

  9. Data acquisition in nuclear and particle physics

    International Nuclear Information System (INIS)

    Renk, B.

    1993-01-01

    An introduction to the methodics of the measurement data acquisition in nuclear and particle physics for students of physics as well as experimental physicists and engineers in research and industry. The contents are: Obtaining of measurement data, digitizing and triggers, memories and microprocessors, bus systems, communication and networks, and examples for data acquisition systems

  10. Nuclear fuel particle and method of production

    International Nuclear Information System (INIS)

    Wagner-Loffler, M.

    1975-01-01

    The core consisting of fuel oxide (UO 2 or Th or Pu oxide) of a fuel particle coated with carbon-contained material is enriched with a small addition (max 6 wt.%) of a Ba or Sr compound (atomic ratio for nuclear fuel oxide Ba being 5 - 10 : 1) which is to prevent fission products breaking the protective carbon and/or silicon carbide coating; the Ba or Sr molybdate generated is to reduce the pressure of the carbon dioxide produced. Methods to manufacture such nuclear fuel particles are proposed where 1) an agglomerisation and shaping of the spheres in a fast cycling bowle and 2) a formation of drops from a colloidal solution which are made to congeal in a liquid paraffin column, take place followed by the pyrolytic coating of the particles. (UWI/LH) [de

  11. Bibliography of integral charged particle nuclear data

    International Nuclear Information System (INIS)

    Holden, N.E.; Burrows, T.W.

    1982-03-01

    This publication is the second supplement to the archival edition of the National Nuclear Data Center's charged-particle bibliography. This supplement contains citations to all references scanned since March 15, 1981, and all corrections and additions to previous citations, and indexes all data received in the international exchanged format (EXFOR). The primary goal of the bibliography has been to satisfy the need expressed by the Nuclear Reaction Data Center Network for a concise and comprehensive bibliography of integral charged-particle cross section data and to provide an index of data exchanged among the members. In 1980, coverage was expanded to include differential data relevant to charged-particle-induced neutron-source reactions

  12. Independent verification in operations at nuclear power plants

    International Nuclear Information System (INIS)

    Donderi, D.C.; Smiley, A.; Ostry, D.J.; Moray, N.P.

    1995-09-01

    A critical review of approaches to independent verification in operations used in nuclear power plant quality assurance programs in other countries, was conducted for this study. This report identifies the uses of independent verification and provides an assessment of the effectiveness of the various approaches. The findings indicate that at Canadian nuclear power plants as much, if not more, independent verification is performed than at power plants in the other countries included in the study. Additional requirements in this area are not proposed for Canadian stations. (author)

  13. Nuclear track radiography of 'hot' aerosol particles

    International Nuclear Information System (INIS)

    Boulyga, S.F.; Kievitskaja, A.I.; Kievets, M.K.; Lomonosova, E.M.; Zhuk, I.V.; Yaroshevich, O.I.; Perelygin, V.P.; Petrova, R.; Brandt, R.; Vater, P.

    1999-01-01

    Nuclear track radiography was applied to identify aerosol 'hot' particles which contain elements of nuclear fuel and fallout after Chernobyl NPP accident. For the determination of the content of transuranium elements in radioactive aerosols the measurement of the α-activity of 'hot' particles by SSNTD was used in this work, as well as radiography of fission fragments formed as a result of the reactions (n,f) and (γ,f) in the irradiation of aerosol filters by thermal neutrons and high energy gamma quanta. The technique allowed the sizes and alpha-activity of 'hot' particles to be determined without extracting them from the filter, as well as the determination of the uranium content and its enrichment by 235 U, 239 Pu and 241 Pu isotopes. Sensitivity of determination of alpha activity by fission method is 5x10 -6 Bq per particle. The software for the system of image analysis was created. It ensured the identification of track clusters on an optical image of the SSNTD surface obtained through a video camera and the determination of size and activity of 'hot' particles

  14. Future directions in nuclear and particle physics

    International Nuclear Information System (INIS)

    Vogt, E.

    1988-09-01

    With the advent of the standard model of quarks, leptons and unified forces one has achieved an understanding of the wealth of data in particle physics and provided a new basis for the understanding of nuclei and hadrons. In particle physics one now seeks to improve the standard model and to go beyond it. In nuclear physics one enquires about the role of quarks and gluons in the dynamics of strongly interacting systems. To answer these new questions an impressive network of large accelerator facilities, including CEBAF, is under construction or in the proposal stage. A global view of this network and its physics is given. (Author) (3 figs.)

  15. PSI nuclear and particle physics newsletter 1989

    International Nuclear Information System (INIS)

    Frosch, R.; Furrer, F.

    1990-01-01

    The present newsletter contains reports on nuclear and particle physics supported by the F1 division of PSI. Groups were invited to present new preliminary or final results obtained in 1989. As usual there has been no refereeing. The contributions must not be quoted without previous consultation with the authors. Spokespersons are indicated by superscripts 'S' following their names in the headings of the contributions. (author) 85 figs., 10 tabs., 307 refs

  16. PSI nuclear and particle physics newsletter 1988

    International Nuclear Information System (INIS)

    Frosch, R.; Furrer, F.

    1989-01-01

    The present Newsletter contains reports on nuclear and particle physics supported by the F1 division of PSI. Groups were invited to present new preliminary or final results obtained in 1989. As usual there has been no refereeing. The contributions must not be quoted without previous consultation with the authors. Spokespersons are indicated by superscripts 'S' following their names in the headings of the contributions. (author) 65 figs., 9 tabs., 189 refs

  17. Selected exercises in particle and nuclear physics

    CERN Document Server

    Bianchini, Lorenzo

    2018-01-01

    This book presents more than 300 exercises, with guided solutions, on topics that span both the experimental and the theoretical aspects of particle physics. The exercises are organized by subject, covering kinematics, interactions of particles with matter, particle detectors, hadrons and resonances, electroweak interactions and flavor physics, statistics and data analysis, and accelerators and beam dynamics. Some 200 of the exercises, including 50 in multiple-choice format, derive from exams set by the Italian National Institute for Nuclear Research (INFN) over the past decade to select its scientific staff of experimental researchers. The remainder comprise problems taken from the undergraduate classes at ETH Zurich or inspired by classic textbooks. Whenever appropriate, in-depth information is provided on the source of the problem, and readers will also benefit from the inclusion of bibliographic details and short dissertations on particular topics. This book is an ideal complement to textbooks on experime...

  18. Supralinearity and particle discrimination in nuclear emulsion

    International Nuclear Information System (INIS)

    Katz, R.; Larsson, L.; Pinkerton, F.E.; Benton, E.V.

    1977-01-01

    Nuclear emulsions may be desensitized in manufacture and/or may be so processed as to discriminate against small latent image sites; to yield supralinear sensitometric response after x-irradiation; and to discriminate against lightly ionizing radiations in favor of heavily ionizing particles. In a circumstance where one electron passing through an emulsion grain is unlikely to generate a latent image sufficiently large to yield a visible grain after development, some larger number of electrons is required, resulting in 'many-hit' statistics, supralinearity, and particle discrimination: for lightly ionizing particles are not likely to generate more than one delta-ray (secondary electron) in their passage through or near a grain. Since these properties are analogous to the response of many biological cells to ionizing radiations, such emulsion-developer combinations have the potential to mimic the response of biological systems to particulate radiations of different charge and speed. (author)

  19. Particle bed reactor nuclear rocket concept

    International Nuclear Information System (INIS)

    Ludewig, H.

    1991-01-01

    The particle bed reactor nuclear rocket concept consists of fuel particles (in this case (U,Zr)C with an outer coat of zirconium carbide). These particles are packed in an annular bed surrounded by two frits (porous tubes) forming a fuel element; the outer one being a cold frit, the inner one being a hot frit. The fuel element are cooled by hydrogen passing in through the moderator. These elements are assembled in a reactor assembly in a hexagonal pattern. The reactor can be either reflected or not, depending on the design, and either 19 or 37 elements, are used. Propellant enters in the top, passes through the moderator fuel element and out through the nozzle. Beryllium used for the moderator in this particular design to withstand the high radiation exposure implied by the long run times

  20. Nuclear track radiography of 'hot' aerosol particles

    CERN Document Server

    Boulyga, S F; Kievets, M K; Lomonosova, E M; Zhuk, I V; Yaroshevich, O I; Perelygin, V P; Petrova, R I; Brandt, R; Vater, P

    1999-01-01

    Nuclear track radiography was applied to identify aerosol 'hot' particles which contain elements of nuclear fuel and fallout after Chernobyl NPP accident. For the determination of the content of transuranium elements in radioactive aerosols the measurement of the alpha-activity of 'hot' particles by SSNTD was used in this work, as well as radiography of fission fragments formed as a result of the reactions (n,f) and (gamma,f) in the irradiation of aerosol filters by thermal neutrons and high energy gamma quanta. The technique allowed the sizes and alpha-activity of 'hot' particles to be determined without extracting them from the filter, as well as the determination of the uranium content and its enrichment by sup 2 sup 3 sup 5 U, sup 2 sup 3 sup 9 Pu and sup 2 sup 4 sup 1 Pu isotopes. Sensitivity of determination of alpha activity by fission method is 5x10 sup - sup 6 Bq per particle. The software for the system of image analysis was created. It ensured the identification of track clusters on an optical imag...

  1. Techniques used for charged particle nuclear data evaluation at CNDC

    International Nuclear Information System (INIS)

    Zhuang Youxiang; Sun Zuxun

    1993-01-01

    The methods and techniques used for Charged Particle Nuclear Data (CPND) evaluation at Chinese Nuclear Data Center (CNDC) are summarized, including compilation and evaluation of experimental data, nuclear reaction theory and model calculation, systematics research and comprehensive recommendation etc

  2. Semiconductor detectors in nuclear and particle physics

    International Nuclear Information System (INIS)

    Rehak, P.; Gatti, E.

    1992-01-01

    Semiconductor detectors for elementary particle physics and nuclear physics in the energy range above 1 GeV are briefly reviewed. In these two fields semiconductor detectors are used mainly for the precise position sensing. In a typical experiment, the position of a fast charged particle crossing a relatively thin semiconductor detector is measured. The position resolution achievable by semiconductor detectors is compared with the resolution achievable by gas filled position sensing detectors. Semiconductor detectors are divided into two groups: Classical semiconductor diode detectors and semiconductor memory detectors. Principles of the signal formation and the signal read-out for both groups of detectors are described. New developments of silicon detectors of both groups are reported

  3. Semiconductor detectors in nuclear and particle physics

    International Nuclear Information System (INIS)

    Rehak, P.; Gatti, E.

    1995-01-01

    Semiconductor detectors for elementary particle physics and nuclear physics in the energy range above 1 GeV are briefly reviewed. In these two fields semiconductor detectors are used mainly for the precise position sensing. In a typical experiment, the position of a fast charged particle crossing a relatively thin semiconductor detector is measured. The position resolution achievable by semiconductor detectors is compared with the resolution achievable by gas filled position sensing detectors. Semiconductor detectors are divided into two groups; (i) classical semiconductor diode detectors and (ii) semiconductor memory detectors. Principles of the signal formation and the signal read-out for both groups of detectors are described. New developments of silicon detectors of both groups are reported. copyright 1995 American Institute of Physics

  4. Is it also possible to describe a system of correlated nucleons in its ground state by an independent particle state

    International Nuclear Information System (INIS)

    Desplanques, B.

    1989-12-01

    The concept of nucleon in nuclei has often been referred to in recent literature. What it is used for is rarely precised however. In this paper, it is shown (or reminded) that the nucleon in nuclei is a model dependent object. As an illustration, it is shown that nuclear matter in its ground state may be described to a good approximation, if not exactly, by an independent particle state and that the on-shell G-matrix used in calculating its binding energy gets its effective character from that of those particles. The expression of these particles in terms of free nucleon operators is given

  5. Nuclear, particle and many body physics

    CERN Document Server

    Morse, Philip M; Feshbach, Herman

    2013-01-01

    Nuclear, Particle and Many Body Physics, Volume II, is the second of two volumes dedicated to the memory of physicist Amos de-Shalit. The contributions in this volume are a testament to the respect he earned as a physicist and of the warm and rich affection he commanded as a personal friend. The book contains 41 chapters and begins with a study on the renormalization of rational Lagrangians. Separate chapters cover the scattering of high energy protons by light nuclei; approximation of the dynamics of proton-neutron systems; the scattering amplitude for the Gaussian potential; Coulomb excitati

  6. Hot spots in nuclear and particle physics

    International Nuclear Information System (INIS)

    Stelte, N.

    1981-01-01

    The aim of the present thesis was the study of the phenomenon of the pre-equilibrium process in nuclear and particle physics in the framework of the HS picture. From the comparison of the HS model with inclusive experiments of nuclear physics it could be concluded, that HS's can have an important portion of the pre-equilibrium spectrum. In reactions of hadrons and lighter nuclei with heavy target nuclei the dependence of the HS-induced spectrum from the target mass, the detector angle, the kinetic energy, and as far as data were available, from the kind of the emitted particle as function of the drift parameter, the maximal temperature, and the velocity could be indicated. For forward angles a qualitative to quantitative agreement with the studied data could by shown. For backward angles a quantitative agreement resulted which suggests the conclusion that this angular range is determined by the HS effect even about three orders of magnitude of the incident energy. (orig./HSI) [de

  7. Techniques for nuclear and particle physics experiments. 2. rev. ed.

    International Nuclear Information System (INIS)

    Leo, W.R.

    1992-01-01

    This book is an outgrowth of an advanced laboratory course in experimental nuclear and particle physics the author gave to physics majors at the University of Geneva during the years 1978- 1983. The course was offered to third and fourth year students, the latter of which had, at this point in their studies, chosen to specialize in experimental nuclear or particle physics. This implied that they would go on to do a 'diplome' thesis with one of the high- or intermediate-energy research groups in the physics department. The format of the course was such that the students were required to concentrate on only one experiment during the trimester, rather than perform a series of experiments as is more typical of a traditional course of this type. Their tasks thus included planning the experiment, learning the relevant techniques, setting up and troubleshooting the measuring apparatus, calibration, data-taking and analysis, as well as responsibility for maintaining their equipment, i.e., tasks resembling those in a real experiment. This more intensive involvement provided the students with a better understanding of the experimental problems encountered in a professional experiment and helped instill a certain independence and confidence which would prepare them for entry into a research group in the department. Teaching assistants were presented to help the students during the trimester and a series of weekly lectures was also given on various topics in experimental nuclear and particle physics. This included general information on detectors, nuclear electronics, statistics, the interaction of radiation in matter, etc., and a good deal of practical information for actually doing experiments. (orig.) With 254 figs

  8. Independent peer review of nuclear safety computer codes

    International Nuclear Information System (INIS)

    Boyack, B.E.; Jenks, R.P.

    1993-01-01

    A structured, independent computer code peer-review process has been developed to assist the US Nuclear Regulatory Commission (NRC) and the US Department of Energy in their nuclear safety missions. This paper describes a structured process of independent code peer review, benefits associated with a code-independent peer review, as well as the authors' recent peer-review experience. The NRC adheres to the principle that safety of plant design, construction, and operation are the responsibility of the licensee. Nevertheless, NRC staff must have the ability to independently assess plant designs and safety analyses submitted by license applicants. According to Ref. 1, open-quotes this requires that a sound understanding be obtained of the important physical phenomena that may occur during transients in operating power plants.close quotes The NRC concluded that computer codes are the principal products to open-quotes understand and predict plant response to deviations from normal operating conditionsclose quotes and has developed several codes for that purpose. However, codes cannot be used blindly; they must be assessed and found adequate for the purposes they are intended. A key part of the qualification process can be accomplished through code peer reviews; this approach has been adopted by the NRC

  9. A new stage of nuclear electronics-particle electronics

    International Nuclear Information System (INIS)

    Xi Deming

    1987-01-01

    The rapid development of high energy physics experiments has pushed the nuclear electronics to a new stage, i.e. the particle electronics. In this paper the background, main features and recent trends of the particle electronics are expounded

  10. Particles identification using nuclear emulsion in OPERA

    International Nuclear Information System (INIS)

    Manai, K.

    2007-10-01

    The Opera experiment will try to confirm the ν μ → ν τ oscillations by the appearance of the ν τ in a pure ν μ beam. Indeed, a neutrino beam almost pure is produced at CERN (CNGS Beam) and sent to the Opera detector. The detector is composed of two muons spectrometers and a target formed by walls of bricks. Each brick is an alternation of lead plates and emulsions. This modular structure allows to reconstruct the kink topology of the τ lepton decay with a high spatial resolution. The great challenge of the Opera experiment is to detect the ν τ interactions with the less uncertainty. To reduce this uncertainty it is essential to identify with the greatest efficiency any background event not including a tau particle. My work permits to reduce background. My principal contribution concerns the selection development, the reconstruction and the muons identification at low energy. This work is based on the setting of variables related to the deposit energy and the multiple scattering. Previously, only deposit energy was used in the analyses of pion/muon separation. This study allows doubling the muon identification efficiency at low energy. This leads to increase the background events rejection in Opera and to decrease the contamination by 30%. I also studied the nuclear emulsions capacity to identify charged particles through the analysis of a test beam carried out by the Nagoya group. This test contains protons and pions with different energies. My work proves that the European scan system gives comparable results with those obtained by the Japanese scan system. (author)

  11. Nuclear Track Detectors. Searches for Exotic Particles

    CERN Document Server

    Giacomelli, Giorgio

    2008-01-01

    We used Nuclear Track Detectors (NTD) CR39 and Makrofol for many purposes: i) Exposures at the SPS and at lower energy accelerator heavy ion beams for calibration purposes and for fragmentation studies. ii) Searches for GUT and Intermediate Mass Magnetic Monopoles (IMM), nuclearites, Q-balls and strangelets in the cosmic radiation. The MACRO experiment in the Gran Sasso underground lab, with ~1000 m^2 of CR39 detectors (plus scintillators and streamer tubes), established an upper limit for superheavy GUT poles at the level of 1.4x10^-16 cm^-2 s^-1 sr^-1 for 4x10^-5 particles. iii) Environmental studies, radiation monitoring, neutron dosimetry.

  12. Qualification and actuation of the independent technical supervision organisms in nuclear power plants and others facilities

    International Nuclear Information System (INIS)

    1999-09-01

    This norm presents the following objectives: establishment of the Brazilian National Nuclear Energy Commission requirements for qualifying an institution as independent technical supervision organization, in a specific area of activity related to nuclear power plants and others nuclear or radioactive facilities as appropriated; regulation of the independent technical supervision and others complementary activities to be executed by an independent technical supervision organism

  13. Large area nuclear particle detectors using ET materials

    International Nuclear Information System (INIS)

    1987-08-01

    The purpose of this SBIR Phase 1 feasibility effort was to demonstrate the usefulness of Quantex electron-trapping (ET) materials for spatial detection of nuclear particles over large areas. This demonstration entailed evaluating the prompt visible scintillation as nuclear particles impinged on films of ET materials, and subsequently detecting the nuclear particle impingement information pattern stored in the ET material, by means of the visible-wavelength luminescence produced by near-infrared interrogation. Readily useful levels of scintillation and luminescence outputs are demonstrated

  14. Improvement in the independence of relaxation method-based particle tracking velocimetry

    International Nuclear Information System (INIS)

    Jia, P; Wang, Y; Zhang, Y

    2013-01-01

    New techniques are developed to improve the independence of relaxation method-based particle tracking velocimetry (RM-PTV). Firstly, Delaunay tessellation (DT) is employed to form clusters of neighboring particles with similar motion in the same frame; and then a bidirectional calculation concept is adopted to improve the way of particle pairing. These new techniques are tested with both self-defined particle images and the particle image velocimetry standard synthetic particle images. The results indicate that the DT method performs well and efficiently in determining the particle clusters, and the particle pairing process is well optimized by the bidirectional calculation concept. With these methods, three computation parameters are eliminated, which makes RM-PTV more autonomous in applications. (paper)

  15. High-energy nuclear optics of polarized particles

    CERN Document Server

    Baryshevsky, Vladimir G

    2012-01-01

    The various phenomena caused by refraction and diffraction of polarized elementary particles in matter have opened up a new research area in the particle physics: nuclear optics of polarized particles. Effects similar to the well-known optical phenomena such as birefringence and Faraday effects, exist also in particle physics, though the particle wavelength is much less than the distance between atoms of matter. Current knowledge of the quasi-optical effects, which exist for all particles in any wavelength range (and energies from low to extremely high), will enable us to investigate different properties of interacting particles (nuclei) in a new aspect. This pioneering book will provide detailed accounts of quasi-optical phenomena in the particle polarization, and will interest physicists and professionals in experimental particle physics.

  16. Trojan horse particle invariance: The impact on nuclear astrophysics

    International Nuclear Information System (INIS)

    Pizzone, R. G.; La Cognata, M.; Spitaleri, C.; Bertulani, C. A.; Mukhamedzhanov, A. M.; Blokhintsev, L. D.; Lamia, L.; Spartá, R.; Tumino, A.

    2014-01-01

    In the current picture of nuclear astrophysics indirect methods and, in particular, the Trojan Horse Method cover a crucial role for the measurement of charged particle induced reactions cross sections of astrophysical interest, in the energy range required by the astrophysical scenarios. To better understand its cornerstones and its applications to physical cases many tests were performed to verify all its properties and the possible future perspectives. The key to the method is the quasi-free break-up and some of its properties will be investigated in the present work. In particular, the Trojan Horse nucleus invariance will be studied and previous studies will be extended to the cases of the binary d(d, p)t and 6 Li(d,α) 4 He reactions, which were tested using different quasi-free break-up's, namely 6 Li and 3 He. The astrophysical S(E)-factor were then extracted with the Trojan Horse formalism applied to the two different break-up schemes and compared with direct data as well as with previous indirect investigations. The very good agreement confirms the independence of binary indirect cross section on the chosen spectator particle also for these reactions

  17. Trojan horse particle invariance: The impact on nuclear astrophysics

    Energy Technology Data Exchange (ETDEWEB)

    Pizzone, R. G.; La Cognata, M. [Laboratori Nazionali del Sud - INFN, Catania (Italy); Spitaleri, C. [Universitá di Catania and Laboratori Nazionali del Sud - INFN (Italy); Bertulani, C. A. [Texas A and M University, Commerce (United States); Mukhamedzhanov, A. M. [Texas A and M University, College Station, Texas (United States); Blokhintsev, L. D. [Moscow State University, Moscow (Russian Federation); Lamia, L.; Spartá, R. [Universitá di Catania and Laboratori Nazionali del Sud - INFN, Catania (Italy); Tumino, A. [Universitá Kore, Enna (Italy)

    2014-05-02

    In the current picture of nuclear astrophysics indirect methods and, in particular, the Trojan Horse Method cover a crucial role for the measurement of charged particle induced reactions cross sections of astrophysical interest, in the energy range required by the astrophysical scenarios. To better understand its cornerstones and its applications to physical cases many tests were performed to verify all its properties and the possible future perspectives. The key to the method is the quasi-free break-up and some of its properties will be investigated in the present work. In particular, the Trojan Horse nucleus invariance will be studied and previous studies will be extended to the cases of the binary d(d, p)t and {sup 6}Li(d,α){sup 4}He reactions, which were tested using different quasi-free break-up's, namely {sup 6}Li and {sup 3}He. The astrophysical S(E)-factor were then extracted with the Trojan Horse formalism applied to the two different break-up schemes and compared with direct data as well as with previous indirect investigations. The very good agreement confirms the independence of binary indirect cross section on the chosen spectator particle also for these reactions.

  18. Nuclei and particles. An introduction to nuclear and subnuclear physics

    International Nuclear Information System (INIS)

    Serge, E.

    1977-01-01

    A broad introduction is given to nuclear and subnuclear physics. Major divisions of the book include radiation and tools for studying the nucleus, elements of the structure, properties, and reactions of nuclei, and a semiphenomenological approach to elementary particles

  19. Transport of large particles released in a nuclear accident

    International Nuclear Information System (INIS)

    Poellaenen, R.; Toivonen, H.; Lahtinen, J.; Ilander, T.

    1995-10-01

    Highly radioactive particulate material may be released in a nuclear accident or sometimes during normal operation of a nuclear power plant. However, consequence analyses related to radioactive releases are often performed neglecting the particle nature of the release. The properties of the particles have an important role in the radiological hazard. A particle deposited on the skin may cause a large and highly non-uniform skin beta dose. Skin dose limits may be exceeded although the overall activity concentration in air is below the level of countermeasures. For sheltering purposes it is crucial to find out the transport range, i.e. the travel distance of the particles. A method for estimating the transport range of large particles (aerodynamic diameter d a > 20 μm) in simplified meteorological conditions is presented. A user-friendly computer code, known as TROP, is developed for fast range calculations in a nuclear emergency. (orig.) (23 refs., 13 figs.)

  20. Transport of large particles released in a nuclear accident

    Energy Technology Data Exchange (ETDEWEB)

    Poellaenen, R; Toivonen, H; Lahtinen, J; Ilander, T

    1995-10-01

    Highly radioactive particulate material may be released in a nuclear accident or sometimes during normal operation of a nuclear power plant. However, consequence analyses related to radioactive releases are often performed neglecting the particle nature of the release. The properties of the particles have an important role in the radiological hazard. A particle deposited on the skin may cause a large and highly non-uniform skin beta dose. Skin dose limits may be exceeded although the overall activity concentration in air is below the level of countermeasures. For sheltering purposes it is crucial to find out the transport range, i.e. the travel distance of the particles. A method for estimating the transport range of large particles (aerodynamic diameter d{sub a} > 20 {mu}m) in simplified meteorological conditions is presented. A user-friendly computer code, known as TROP, is developed for fast range calculations in a nuclear emergency. (orig.) (23 refs., 13 figs.).

  1. Charged particle-induced nuclear fission reactions

    Indian Academy of Sciences (India)

    The nuclear fission phenomenon continues to be an enigma, even after nearly 75 years of its discovery. Considerable progress has been made towards understanding the fission process. Both light projectiles and heavy ions have been employed to investigate nuclear fission. An extensive database of the properties of ...

  2. Ultrasonic-resonator-combined apparatus for purifying nuclear aerosol particles

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Suxia; Zhang, Quanhu; Li, Sufen; Chen, Chen; Su, Xianghua [Xi' an Hi-Tech Institute, Xi' an (China)

    2017-12-15

    The radiation hazards of radionuclides in the air arising from the storage room of nuclear devices to the operators cannot be ignored. A new ultrasonic-resonator-combined method for purifying nuclear aerosol particles is introduced. To remove particles with diameters smaller than 0.3 μm, an ultrasonic chamber is induced to agglomerate these submicron particles. An apparatus which is used to purify the nuclear aerosol particles is described in the article. The apparatus consists of four main parts: two filtering systems, an ultrasonic chamber and a high-pressure electrostatic precipitator system. Finally, experimental results demonstrated the effectiveness of the implementation of the ultrasonic resonators. The feasibility of the method is proven by its application to the data analysis of the experiments.

  3. Independent assessment of forseeable problems in the nuclear fuel cycle

    International Nuclear Information System (INIS)

    1975-01-01

    Information is presented concerning the U. S. nuclear fuel cycle business including investment requirements; nuclear power growth projection; reliability of uranium supply; enrichment facilities; plutonium recycle; safeguards; and insurance

  4. Bibliography of integral charged particle nuclear data. Archival edition

    International Nuclear Information System (INIS)

    Burrows, T.W.; Dempsey, P.

    1980-03-01

    This is the fourth annual edition of the National Nuclear Data Center charged-particle bibliography. This edition is cumulative and supersedes the previous editions. The bibliography's primary aims are to satisfy the need for a concise and comprehensive index of integral charged-particle cross section data and to provide an index of charged-particle data compiled in the international exchange format. References in this Part are by target for the various incident charged particles (in order of increasing A). The present publication is an archival volume; future publications will be cumulative supplements to this edition

  5. Chapter 2. Peculiarities of radioactive particle formation and isotope fractionation resulted from underground nuclear explosions

    International Nuclear Information System (INIS)

    1996-01-01

    Radioactive particles, forming terrain fallouts from underground nuclear explosion differ sufficiently from radioactive particles, produced by atmospheric nuclear explosions. Patterns of underground nuclear explosion development, release of radioactivity to the atmosphere, formation of a cloud and base surge, peculiarities of formed radioactive particles, data on isotope fractionation in radioactive particles are presented. Scheme of particle activation, resulted from underground explosions is given

  6. Cellular stress stimulates nuclear localization signal (NLS) independent nuclear transport of MRJ

    Science.gov (United States)

    Andrews, Joel F.; Sykora, Landon J.; Barik-Letostak, Tiasha; Menezes, Mitchell E.; Mitra, Aparna; Barik, Sailen; Shevde, Lalita A.; Samant, Rajeev S.

    2012-01-01

    HSP40 family member MRJ (DNAJB6) has been in the spot light for its relevance to Huntington’s, Parkinson’s diseases, limb-girdle muscular dystrophy, placental development, neural stem cells, cell cycle and malignancies such as breast cancer and melanoma. This gene has two spliced variants coding for 2 distinct proteins with significant homology. However, MRJ(L) (large variant) is predominantly localized to the nucleus whereas MRJ(S) (small variant) is predominantly cytoplasmic. Interestingly MRJ(S) translocates to the nucleus in response to heat shock. The classical heat shock proteins respond to crises (stress) by increasing the number of molecules, usually by transcriptional up-regulation. Our studies imply that a quick increase in the molar concentration of MRJ in the nuclear compartment is a novel method by which MRJ responds to stress. We found that MRJ(S) shows NLS (nuclear localization signal) independent nuclear localization in response to heat shock and hypoxia. The specificity of this response is realized due to lack of such response by MRJ(S) when challenged by other stressors, such as some cytokines or UV light. Deletion analysis has allowed us to narrow down on a 20 amino acid stretch at the C-terminal region of MRJ(S) as a potential stress sensing region. Functional studies indicated that constitutive nuclear localization of MRJ(S) promoted attributes of malignancy such as proliferation and invasiveness overall indicating distinct phenotypic characteristics of nuclear MRJ(S). PMID:22504047

  7. Cellular stress stimulates nuclear localization signal (NLS) independent nuclear transport of MRJ

    International Nuclear Information System (INIS)

    Andrews, Joel F.; Sykora, Landon J.; Barik Letostak, Tiasha; Menezes, Mitchell E.; Mitra, Aparna; Barik, Sailen; Shevde, Lalita A.; Samant, Rajeev S.

    2012-01-01

    HSP40 family member MRJ (DNAJB6) has been in the spot light for its relevance to Huntington's, Parkinson's diseases, limb-girdle muscular dystrophy, placental development, neural stem cells, cell cycle and malignancies such as breast cancer and melanoma. This gene has two spliced variants coding for 2 distinct proteins with significant homology. However, MRJ(L) (large variant) is predominantly localized to the nucleus whereas MRJ(S) (small variant) is predominantly cytoplasmic. Interestingly MRJ(S) translocates to the nucleus in response to heat shock. The classical heat shock proteins respond to crises (stress) by increasing the number of molecules, usually by transcriptional up-regulation. Our studies imply that a quick increase in the molar concentration of MRJ in the nuclear compartment is a novel method by which MRJ responds to stress. We found that MRJ(S) shows NLS (nuclear localization signal) independent nuclear localization in response to heat shock and hypoxia. The specificity of this response is realized due to lack of such response by MRJ(S) when challenged by other stressors, such as some cytokines or UV light. Deletion analysis has allowed us to narrow down on a 20 amino acid stretch at the C-terminal region of MRJ(S) as a potential stress sensing region. Functional studies indicated that constitutive nuclear localization of MRJ(S) promoted attributes of malignancy such as proliferation and invasiveness overall indicating distinct phenotypic characteristics of nuclear MRJ(S).

  8. Cellular stress stimulates nuclear localization signal (NLS) independent nuclear transport of MRJ

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, Joel F.; Sykora, Landon J.; Barik Letostak, Tiasha; Menezes, Mitchell E.; Mitra, Aparna [Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL (United States); Barik, Sailen [Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Science, Cleveland State University, Cleveland, OH (United States); Shevde, Lalita A. [Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL (United States); Samant, Rajeev S., E-mail: rsamant@usouthal.edu [Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL (United States)

    2012-06-10

    HSP40 family member MRJ (DNAJB6) has been in the spot light for its relevance to Huntington's, Parkinson's diseases, limb-girdle muscular dystrophy, placental development, neural stem cells, cell cycle and malignancies such as breast cancer and melanoma. This gene has two spliced variants coding for 2 distinct proteins with significant homology. However, MRJ(L) (large variant) is predominantly localized to the nucleus whereas MRJ(S) (small variant) is predominantly cytoplasmic. Interestingly MRJ(S) translocates to the nucleus in response to heat shock. The classical heat shock proteins respond to crises (stress) by increasing the number of molecules, usually by transcriptional up-regulation. Our studies imply that a quick increase in the molar concentration of MRJ in the nuclear compartment is a novel method by which MRJ responds to stress. We found that MRJ(S) shows NLS (nuclear localization signal) independent nuclear localization in response to heat shock and hypoxia. The specificity of this response is realized due to lack of such response by MRJ(S) when challenged by other stressors, such as some cytokines or UV light. Deletion analysis has allowed us to narrow down on a 20 amino acid stretch at the C-terminal region of MRJ(S) as a potential stress sensing region. Functional studies indicated that constitutive nuclear localization of MRJ(S) promoted attributes of malignancy such as proliferation and invasiveness overall indicating distinct phenotypic characteristics of nuclear MRJ(S).

  9. Cellular stress stimulates nuclear localization signal (NLS) independent nuclear transport of MRJ

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, Joel F.; Sykora, Landon J.; Barik Letostak, Tiasha; Menezes, Mitchell E.; Mitra, Aparna [Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL (United States); Barik, Sailen [Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Science, Cleveland State University, Cleveland, OH (United States); Shevde, Lalita A. [Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL (United States); Samant, Rajeev S., E-mail: rsamant@usouthal.edu [Department of Oncologic Sciences, Mitchell Cancer Institute, University of South Alabama, Mobile, AL (United States)

    2012-06-10

    HSP40 family member MRJ (DNAJB6) has been in the spot light for its relevance to Huntington's, Parkinson's diseases, limb-girdle muscular dystrophy, placental development, neural stem cells, cell cycle and malignancies such as breast cancer and melanoma. This gene has two spliced variants coding for 2 distinct proteins with significant homology. However, MRJ(L) (large variant) is predominantly localized to the nucleus whereas MRJ(S) (small variant) is predominantly cytoplasmic. Interestingly MRJ(S) translocates to the nucleus in response to heat shock. The classical heat shock proteins respond to crises (stress) by increasing the number of molecules, usually by transcriptional up-regulation. Our studies imply that a quick increase in the molar concentration of MRJ in the nuclear compartment is a novel method by which MRJ responds to stress. We found that MRJ(S) shows NLS (nuclear localization signal) independent nuclear localization in response to heat shock and hypoxia. The specificity of this response is realized due to lack of such response by MRJ(S) when challenged by other stressors, such as some cytokines or UV light. Deletion analysis has allowed us to narrow down on a 20 amino acid stretch at the C-terminal region of MRJ(S) as a potential stress sensing region. Functional studies indicated that constitutive nuclear localization of MRJ(S) promoted attributes of malignancy such as proliferation and invasiveness overall indicating distinct phenotypic characteristics of nuclear MRJ(S).

  10. Intersections between particle and nuclear physics

    International Nuclear Information System (INIS)

    Van Oers, W.T.H.

    1992-01-01

    This report contains papers on High Energy Physics and Nuclear Physics research. Some of areas covered are: antiproton physics; detectors and instrumentation; accelerator facilities; hadron physics; mesons and lepton decays; physics with electrons and muons; physics with relativistic heavy ions; physics with spin; neutrinos and nonaccelerator physics. The individual paper have been indexed separately elsewhere

  11. Timescale of particle emission using nuclear interferometry

    International Nuclear Information System (INIS)

    Ardouin, D.; Goujdami, D.; Guilbault, F.; Lebrun, C.; Erazmus, B.; Dabrowski, H.; Durand, D.; Lautridou, P.; Boisgard, R.; Quebert, J.; Carjan, N.

    1989-01-01

    A review of meson and baryon correlations at various energies is presented. An attempt, to focus on possible lifetime effects contained in existing data,is made. Data at 94 and 44 MeV/u, where experimental conditions are chosen, trying to study the lifetime of light particle emission using two particle correlations, are discussed. The temperature of a thermalized system is obtained, using the relative population of cluster excited states. It is shown that either quantum statistical fluctuations or Coulomb interactions play an important role in the trends of the correlation-functions at very low relative momenta. In the case of 1 60 and Ar induced reactions on heavy targets, a lifetime of the order of 10 -21 seconds is estimated. Temperature measurements for Ar + Ag system show that part of the excitation energy is not converted into thermal energy

  12. Bibliography of integral charged particle nuclear data

    Energy Technology Data Exchange (ETDEWEB)

    Burrows, T.W.; Burt, J.S.

    1977-03-01

    This bibliography is divided into three main sections covering experimental, theoretical, and review references. The review section also includes compilation and evaluation references. Each section contains two subsections. The main subsection contains all references satisfying the criteria noted above and the second subsection is devoted to isotope production. The main subsections are ordered by increasing Z and A of the incident particle, then by increasing Z and A of the target nucleus. Within this order, the entries are ordered by residual nucleus and quantity (e.g., sigma(E)). Finally, the entries are ordered by outgoing particles or processes. All entries which have the same target, reaction, and quantity are grouped under a common heading with the most recent reference first. As noted above the second subsection is devoted to isotope production and is limited in the information it carries. Only those references which contain data on a definite residual nucleus or group of nuclei (e.g., fission fragments) are included in these subsections. Entries within these second subsections are ordered by increasing Z and A of the isotope produced and then by quantity. All references containing data on the same isotope production and quantity are grouped together. All lines within a group are ordered by increasing Z and A of the target and then of the incident particle. The final ordering is by increasing minimum energy.

  13. Meta-material for nuclear particle detection

    Science.gov (United States)

    Merlo, V.; Salvato, M.; Lucci, M.; Ottaviani, I.; Cirillo, M.; Scherillo, A.; Schooneveld, E. M.; Vannozzi, A.; Celentano, G.; Pietropaolo, A.

    2017-02-01

    Superconducting strips coated with boron were engineered with a view to subnuclear particle detection. Combining the characteristics of boron as a generator of α-particles (as a consequence of neutron absorption) and the ability of superconducting strips to act as resistive switches, it is shown that fabricated Nb-boron and NbN-boron strips represent a promising basis for implementing neutron detection devices. In particular, the superconducting transition of boron-coated NbN strips generates voltage outputs of the order of a few volts thanks to the relatively higher normal state resitivity of NbN with respect to Nb. This result, combined with the relatively high transition temperature of NbN (of the order of 16 K for the bulk material), is an appealing prospect for future developments. The coated strips are meta-devices since their constituting material does not exist in nature and it is engineered to accomplish a specific task, i.e. generate an output voltage signal upon α-particle irradiation.

  14. Plot of charged nuclear particles in polymers

    International Nuclear Information System (INIS)

    Gallardo H, J.I.L.

    1975-01-01

    Experiments were made in order to obtain particle tracks and fission fragments in polymers. To increase the damage the polymer is attacked chemically with a solution of KOH, NaOH or other chemical agent, whose concentration depends of the polymer to be treated, maintaining a constant temperature during the process. To count the tracks which perforate the film, a spark counter with controlled nitrogen atmosphere was constructed. In the experiments which were made in order to detect particles, films of cellulose nitrate known as xylonite, daicel and red paper were used. For the detection of fission products, cellulose triacetate and cellulose polycarbonate films, known as kodacel and kimfol were used. The particle tracks on the treated films were optically counted with a microscope. They had a diameter between 12 and 30 microns, and when the thickness of the film permitted it the tracks consisted in perforations from one to another side of the film. The obtained results have permitted to have the necessary reproducibility for the realization of quantitative analysis of irradiations which can be applied to neutron dosimetry. (author)

  15. Bibliography of integral charged particle nuclear data

    International Nuclear Information System (INIS)

    Burrows, T.W.; Burt, J.S.

    1977-03-01

    This bibliography is divided into three main sections covering experimental, theoretical, and review references. The review section also includes compilation and evaluation references. Each section contains two subsections. The main subsection contains all references satisfying the criteria noted above and the second subsection is devoted to isotope production. The main subsections are ordered by increasing Z and A of the incident particle, then by increasing Z and A of the target nucleus. Within this order, the entries are ordered by residual nucleus and quantity (e.g., sigma(E)). Finally, the entries are ordered by outgoing particles or processes. All entries which have the same target, reaction, and quantity are grouped under a common heading with the most recent reference first. As noted above the second subsection is devoted to isotope production and is limited in the information it carries. Only those references which contain data on a definite residual nucleus or group of nuclei (e.g., fission fragments) are included in these subsections. Entries within these second subsections are ordered by increasing Z and A of the isotope produced and then by quantity. All references containing data on the same isotope production and quantity are grouped together. All lines within a group are ordered by increasing Z and A of the target and then of the incident particle. The final ordering is by increasing minimum energy

  16. Particle-gamma and particle-particle correlations in nuclear reactions using Monte Carlo Hauser-Feshback model

    Energy Technology Data Exchange (ETDEWEB)

    Kawano, Toshihiko [Los Alamos National Laboratory; Talou, Patrick [Los Alamos National Laboratory; Watanabe, Takehito [Los Alamos National Laboratory; Chadwick, Mark [Los Alamos National Laboratory

    2010-01-01

    Monte Carlo simulations for particle and {gamma}-ray emissions from an excited nucleus based on the Hauser-Feshbach statistical theory are performed to obtain correlated information between emitted particles and {gamma}-rays. We calculate neutron induced reactions on {sup 51}V to demonstrate unique advantages of the Monte Carlo method. which are the correlated {gamma}-rays in the neutron radiative capture reaction, the neutron and {gamma}-ray correlation, and the particle-particle correlations at higher energies. It is shown that properties in nuclear reactions that are difficult to study with a deterministic method can be obtained with the Monte Carlo simulations.

  17. Quarks and gluons in nuclear and particle physics

    International Nuclear Information System (INIS)

    Van Hove, L.

    1988-01-01

    This paper provides a broad overview of strong interactions, or nuclear forces, as ones understanding has expanded over the past 25 years. The major particles and models are briefly touched upon. The author expands upon the field theories which have evolved to explain the experimental work, and the present model of quarks and gluons which form the components of hadrons. The standard model has been very successful in explaining much of the newly acquired experimental data. But the property of confinement, where the partons, (quarks and gluons), are not observed seperately has precluded observation of these particles. He touches on the manifestation of these particles in high energy physics, where they model the observed particles and resonances, and are responsible for the production of hadronic jets. However in nuclear physics, one does not need to postulate the existance of these particles to explain the properties of nuclei, until one deals with interaction energies in the range of GeV. The author then touches on the area of ultra-relativistic nuclear physics, where the partons must play a role in the effects which are observed. In particular he discusses deep inelastic lepton scattering on nuclei, the Drell-Yan process in nuclei, and ultra-relativistic nuclear collisions. Finally he gives a brief discussion of the quark-gluon plasma, which is postulated to form during very high energy collisions, manifesting itself as a brief deconfinement of the partons into an equilibrium plasma

  18. Time-independent lattice Boltzmann method calculation of hydrodynamic interactions between two particles

    Science.gov (United States)

    Ding, E. J.

    2015-06-01

    The time-independent lattice Boltzmann algorithm (TILBA) is developed to calculate the hydrodynamic interactions between two particles in a Stokes flow. The TILBA is distinguished from the traditional lattice Boltzmann method in that a background matrix (BGM) is generated prior to the calculation. The BGM, once prepared, can be reused for calculations for different scenarios, and the computational cost for each such calculation will be significantly reduced. The advantage of the TILBA is that it is easy to code and can be applied to any particle shape without complicated implementation, and the computational cost is independent of the shape of the particle. The TILBA is validated and shown to be accurate by comparing calculation results obtained from the TILBA to analytical or numerical solutions for certain problems.

  19. Independent verification in operations at nuclear power plants: Summaries of site visits

    International Nuclear Information System (INIS)

    Donderi, D.C.; Smiley, A.; Ostry, D.J.; Moray, N.P.

    1995-09-01

    A critical review of approaches to independent verification in operations used in nuclear power plant quality assurance programs in other countries was conducted and are detailed in volume 1. This paper is a compilation of the visits to nuclear power plant sites to study independent verification in operations at sites in Canada, USA, Japan, United Kingdom, France and Germany. 3 tabs., 22 figs

  20. A source-independent empirical correction procedure for the fast mobility and engine exhaust particle sizers

    Science.gov (United States)

    Zimmerman, Naomi; Jeong, Cheol-Heon; Wang, Jonathan M.; Ramos, Manuel; Wallace, James S.; Evans, Greg J.

    2015-01-01

    The TSI Fast Mobility Particle Sizer (FMPS) and Engine Exhaust Particle Sizer (EEPS) provide size distributions for 6-560 nm particles with a time resolution suitable for characterizing transient particle sources; however, the accuracy of these instruments can be source dependent, due to influences of particle morphology. The aim of this study was to develop a source-independent correction protocol for the FMPS and EEPS. The correction protocol consists of: (1) broadening the >80 nm size range of the distribution to account for under-sizing by the FMPS and EEPS; (2) applying an existing correction protocol in the 8-93 nm size range; and (3) dividing each size bin by the ratio of total concentration measured by the FMPS or EEPS and a water-based Condensation Particle Counter (CPC) as a surrogate scaling factor to account for particle morphology. Efficacy of the correction protocol was assessed for three sources: urban ambient air, diluted gasoline direct injection engine exhaust, and diluted diesel engine exhaust. Linear regression against a reference instrument, the Scanning Mobility Particle Sizer (SMPS), before and after applying the correction protocol demonstrated that the correction ensured agreement within 20%.

  1. On the independent particle approximation of Gauge theories: a simple example

    International Nuclear Information System (INIS)

    Palladino, B.E.

    1992-08-01

    In this work, the independent particle model formulation is studied as a mean-field approximation of gauge theories using the path integral approach in the framework of quantum electrodynamics in 1+1 dimensions. It is shown how a mean-field approximation scheme can be applied to fit an effective potential to an independent particle model, building a straightforward relation between the model and the associated gauge field theory. An example is made considering the problem of massive Dirac fermions on a line, the so called massive Schwinger model. An interesting result is found, indicating a behaviour of screening of the charges in the relativistic limit of strong coupling. A forthcoming application of the method developed to confining potentials in independent quark models for QCD is in view and is briefly discussed. (author)

  2. Pulse pile-up in nuclear particle detection systems with rapidly varying counting rates

    International Nuclear Information System (INIS)

    Datlowe, D.W.

    1977-01-01

    Pulse pile-up in nuclear particle detection systems is the distortion of the measured pulse height distribution which occurs when there is a significant probability that more than one particle will arrive within the detector resolving time. This paper treats the problem in cases where the probability of pile-up varies on a time scale comparable to the rise time of the detector system electronics. These variations introduce structure into the pulse height distributions which cannot occur for a time-independent pile-up probability. Three classes of problems which exemplify these effects are as follows: 1) Pile-up rejection circuits. 2) Cascaded nuclear decays, in which the lifetime for emission of a second X-ray is comparable to the detector rise time. 3) Bursts of particles where the intensity is modulated on a time scale comparable to the detector rise time. These problems are solved computationally by an extension of a numerical technique previously developed. (Auth.)

  3. Nuclear energy levels and elementary particles

    International Nuclear Information System (INIS)

    de Wet, J.A.

    1982-01-01

    Considering only exchange forces, the binding energies and excited states of nuclei up to 24 Mg are predicted to within charge independence, and there is no reason why the model should not be extended to cover all of the elements. A comparison of theory with experiment shows that the energy of one exchange is 2.56 MeV. Moreover, there is an attractive well of depth 30 MeV, corresponding to the helium nucleus. before exchange forces become operative. A possible explanation of the origin of mesons is also presented

  4. Azimuthal asymmetry of slow particles in high energy nuclear interaction

    International Nuclear Information System (INIS)

    Sarkar, Subir; Goswami, T.D.

    2002-01-01

    An asymmetry in the angular distribution of slow particles in the azimuthal plane has been observed during high energy nuclear disintegration of photo emulsion nuclei exposed to 1.8 GeV/c k - and 20 GeV/c protons. The mechanism of disintegration is not in accordance with the cascade-evaporation model, which is based on isotropic emission of slow particles. Deviation from isotropy indicates that some of the slow particles might be emitted well before the thermal equilibrium is reached in the disintegrating system. (author)

  5. Particle discrimination by an automatic scanner for nuclear emulsion plates

    International Nuclear Information System (INIS)

    Heinecke, W.; Fischer, B.E.

    1976-01-01

    An automatic scanner for nuclear emulsion plates has been improved by adding particle discrimination. By determination of the mean luminosity of tracks in darkfield illumination in addition to the track length a clear discrimination has been obtained, at least for lighter particles. The scanning speed of the original automatic scanner has not been reduced. The scanner works up to 200 times faster than a human scanner. Besides the particle discrimination the determination of the mean track luminosity led to a lower perturbation sensitivity with respect to a high background of accidentally developed silvergrains, scratches in emulsion etc. The reproducibility of the results obtained by the automatic scanner is better than 5%. (Auth.)

  6. Bibliography of integral charged particle nuclear data. Archival edition

    International Nuclear Information System (INIS)

    Burrows, T.W.; Dempsey, P.

    1980-03-01

    This is the fourth annual edition of the National Nuclear Data Center charged-particle bibliography. This edition is cumulative and supersedes the previous editions. The bibliography's primary aims are to satisfy the need for a concise and comprehensive index of integral charged-particle cross section data and to provide an index of charged-particle data compiled in the international exchange format, EXFOR. This part of the publication deals with isotope production; references are ordered by mass of the nuclide produced. The present publication is an archival volume; future publications will be cumulative supplements to this edition

  7. Analytic theory of the energy and time independent particle transport in the plane geometry

    International Nuclear Information System (INIS)

    Simovic, R.D.

    2001-01-01

    An analytic investigation of the energy and time independent particle transport in the plane geometry described by a common anisotropic scattering function is carried out. Regarding the particles with specific diffusion histories in the infinite or the semi-infinite medium, new exact solutions of the corresponding transport equations are analytically derived by means of the Fourier inversion technique. Two particular groups of particles scattered after each successive collision into the directions μ 0, were considered. Its Fourier transformed transport equations have solutions without logarithmic singular points, in the upper part or the lower part of the complex k-plane. The Fourier inversion of solutions are carried out analytically and the obtained formulae represents valid generalization of the expressions for the flux of once scattered particles. (author)

  8. Compressed beam directed particle nuclear energy generator

    International Nuclear Information System (INIS)

    Salisbury, W.W.

    1985-01-01

    This invention relates to the generation of energy from the fusion of atomic nuclei which are caused to travel towards each other along collision courses, orbiting in common paths having common axes and equal radii. High velocity fusible ion beams are directed along head-on circumferential collision paths in an annular zone wherein beam compression by electrostatic focusing greatly enhances head-on fusion-producing collisions. In one embodiment, a steady radial electric field is imposed on the beams to compress the beams and reduce the radius of the spiral paths for enhancing the particle density. Beam compression is achieved through electrostatic focusing to establish and maintain two opposing beams in a reaction zone

  9. Nuclear charge and magnetization densities of single particle states

    International Nuclear Information System (INIS)

    Frois, B.

    1985-01-01

    High energy electron scattering data have recently determined the spatial distributions of nucleons in the center of nuclei with amazing accuracy. For the first time we have access to the structure of the nuclear interior throughout the periodic table. The spatial resolution achieved by high momentum transfer measurements is now sufficient to define clearly the present limits of nuclear theory. The experimental situation is briefly reviewed and the results interpreted in the framework of self-consistent field theory. The shapes of single particle distributions in the nuclear interior are found to be in surprisingly good agreement with the predictions of mean field theory. The effects of correlations are discussed. (orig.)

  10. Nuclear particle track-etched anti-bogus mark

    International Nuclear Information System (INIS)

    He Xiangming; Yan Yushun; Zhang Quanrong

    2003-01-01

    Nuclear particle track-etched anti-bogus mark is a new type of forgery-proof product after engraving gravure printing, thermocolour, fluorescence, laser hologram and metal concealed anti-bogus mark. The mark is manufactured by intricate high technology and the state strictly controlled sensitive nuclear facilities to ensure the mark not to be copied. The pattern of the mark is specially characterized by permeability of liquid to be discriminated from forgery. The genuine mark can be distinguished from sham one by transparent liquid (e.g. water), colorful pen and chemical reagent. The mark has passed the official examination of health safety. It is no danger of nuclear irradiation. (author)

  11. Nuclear charge and magnetization densities of single particle states

    International Nuclear Information System (INIS)

    Frois, B.

    1985-05-01

    High energy electron scattering data have recently determined the spatial distributions of nucleons in the center of nuclei with amazing accuracy. For the first time we have access to the structure of the nuclear interior throughout the periodic table. The spatial resolution achieved by high momentum transfer measurements is now sufficient to define clearly the present limits of nuclear theory. The experimental situation is briefly reviewed and the results interpreted in the framework of self-consistent field theory. The shapes of single particle distributions in the nuclear interior are found to be in surprisingly good agreement with the predictions of mean field theory. The effects of correlations are discussed

  12. Inelastic diffraction nuclear processes with redistribution of particles

    International Nuclear Information System (INIS)

    Sitenko, A.G.; Goryachij, V.V.; Peresypkin, V.V.

    1979-01-01

    The inelastic nuclear processes at high energies with redistribution of particles are described within the framework of the diffraction approach. The capture processes (p,d) and (p,p'n) generated by the high energy nucleon collision with nuclei are considered. The angular distribution of 4 He(p,d) 3 He reaction is calculated and compared with experimental data

  13. Deep inelastic scaling in nuclear and particle physics

    International Nuclear Information System (INIS)

    West, G.B.

    1988-01-01

    These lectures are intended to be a pedagogical introduction to some of the ideas and concepts concerning scaling phenomena which arise in nuclear and particle physics. Topics discussed are: classical scaling and dimensional analysis; non-relativistic treatment; dynamics and scaling; y-scaling; and relativistic treatment (QCD). 22 refs., 16 figs

  14. Morbillivirus nucleoprotein possesses a novel nuclear localization signal and a CRM1-independent nuclear export signal

    International Nuclear Information System (INIS)

    Sato, Hiroki; Masuda, Munemitsu; Miura, Ryuichi; Yoneda, Misako; Kai, Chieko

    2006-01-01

    Morbilliviruses, which belong to the Mononegavirales, replicate its RNA genome in the cytoplasm of the host cell. However, they also form characteristic intranuclear inclusion bodies, consisting of nucleoprotein (N), in infected cells. To analyze the mechanisms of nucleocytoplasmic transport of N protein, we characterized the nuclear localization (NLS) and nuclear export (NES) signals of canine distemper virus (CDV) N protein by deletion mutation and alanine substitution of the protein. The NLS has a novel leucine/isoleucine-rich motif (TGILISIL) at positions 70-77, whereas the NES is composed of a leucine-rich motif (LLRSLTLF) at positions 4-11. The NLS and NES of the N proteins of other morbilliviruses, that is, measles virus (MV) and rinderpest virus (RPV), were also analyzed. The NLS of CDV-N protein is conserved at the same position in MV-N protein, whereas the NES of MV-N protein is located in the C-terminal region. The NES of RPV-N protein is also located at the same position as CDV-N protein, whereas the NLS motif is present not only at the same locus as CDV-N protein but also at other sites. Interestingly, the nuclear export of all these N proteins appears to proceed via a CRM1-independent pathway

  15. Detection of special nuclear materials with the associate particle technique

    International Nuclear Information System (INIS)

    Carasco, Cédric; Deyglun, Clément; Pérot, Bertrand; Eléon, Cyrille; Normand, Stéphane; Sannié, Guillaume; Boudergui, Karim; Corre, Gwenolé; Konzdrasovs, Vladimir; Pras, Philippe

    2013-01-01

    In the frame of the French trans-governmental R and D program against chemical, biological, radiological, nuclear and explosives (CBRN-E) threats, CEA is studying the detection of Special Nuclear Materials (SNM) by neutron interrogation with fast neutrons produced by an associated particle sealed tube neutron generator. The deuterium-tritium fusion reaction produces an alpha particle and a 14 MeV neutron almost back to back, allowing tagging neutron emission both in time and direction with an alpha particle position-sensitive sensor embedded in the generator. Fission prompt neutrons and gamma rays induced by tagged neutrons which are tagged by an alpha particle are detected in coincidence with plastic scintillators. This paper presents numerical simulations performed with the MCNP-PoliMi Monte Carlo computer code and with post processing software developed with the ROOT data analysis package. False coincidences due to neutron and photon scattering between adjacent detectors (cross talk) are filtered out to increase the selectivity between nuclear and benign materials. Accidental coincidences, which are not correlated to an alpha particle, are also taken into account in the numerical model, as well as counting statistics, and the time-energy resolution of the data acquisition system. Such realistic calculations show that relevant quantities of SNM (few kg) can be distinguished from cargo and shielding materials in 10 min acquisitions. First laboratory tests of the system under development in CEA laboratories are also presented.

  16. The French nuclear safety authority, an independent administrative body

    International Nuclear Information System (INIS)

    Lacoste, A.C.

    2007-01-01

    The Nuclear Safety Authority (ASN) is officially responsible for controlling safety and radioactivity in France so as to protect wage-earners, patients, the public and the environment from nuclear-related risks. It draws on the work done by the Institute of Radioprotection and Nuclear Safety (IRSN), and provides information to the public on these questions. The Authority's goal is to ensure an effective, legitimate, impartial and creditable control recognized by the public and serving as an international reference mark. ASN is led by a board of 5 commissaries, has a staff of 420 employees most of them civil servants, has an annual budget of 50 million euros and relies on 11 regional departments

  17. Theories of Variable Mass Particles and Low Energy Nuclear Phenomena

    Science.gov (United States)

    Davidson, Mark

    2014-02-01

    Variable particle masses have sometimes been invoked to explain observed anomalies in low energy nuclear reactions (LENR). Such behavior has never been observed directly, and is not considered possible in theoretical nuclear physics. Nevertheless, there are covariant off-mass-shell theories of relativistic particle dynamics, based on works by Fock, Stueckelberg, Feynman, Greenberger, Horwitz, and others. We review some of these and we also consider virtual particles that arise in conventional Feynman diagrams in relativistic field theories. Effective Lagrangian models incorporating variable mass particle theories might be useful in describing anomalous nuclear reactions by combining mass shifts together with resonant tunneling and other effects. A detailed model for resonant fusion in a deuterium molecule with off-shell deuterons and electrons is presented as an example. Experimental means of observing such off-shell behavior directly, if it exists, is proposed and described. Brief explanations for elemental transmutation and formation of micro-craters are also given, and an alternative mechanism for the mass shift in the Widom-Larsen theory is presented. If variable mass theories were to find experimental support from LENR, then they would undoubtedly have important implications for the foundations of quantum mechanics, and practical applications may arise.

  18. Fine particles from Independence Day fireworks events: chemical characterization and source apportionment

    Science.gov (United States)

    Zhang, J.; Lance, S.; Freedman, J. M.; Yele, S.; Crandall, B.; Wei, X.; Schwab, J. J.

    2017-12-01

    To study the impact of fireworks (FW) events on air quality, aerosol particles from FW displays were measured using a High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) and collocated instruments during the Independence Day holiday 2017 in Albany, NY. Three FW events were identified through potassium ion (K+) signals in the mass spectra. The largest FW event signal measured at two different locations was the Independence Day celebration in Albany, with maximum aerosol concentrations of about 55 ug/m3 at the downtown site and 35 ug/m3 at the uptown site. The aerosol concentration peaked at the uptown site about 2 hours later than at the downtown site. FW events resulted in significant increases in both organic and inorganic (K+, sulfate, chloride) compounds. Among the organics, Positive Matrix Factorization (PMF) identified one special FW organic aerosol factor (FW-OA), which was highly oxidized. The intense emission of FW particles from the Independence Day celebration contributed 76% of total PM1 at the uptown site. The aerosol and wind LiDAR measurements showed two distinct pollution sources, one from the Independence Day FW event in Albany, and another aerosol source transported from other areas, potentially associated with other town's FW events.

  19. Nuclear track radiography of 'hot' aerosol particles

    Energy Technology Data Exchange (ETDEWEB)

    Boulyga, S.F.; Kievitskaja, A.I.; Kievets, M.K.; Lomonosova, E.M.; Zhuk, I.V.; Yaroshevich, O.I.; Perelygin, V.P.; Petrova, R.; Brandt, R.; Vater, P

    1999-06-01

    Nuclear track radiography was applied to identify aerosol 'hot' particles which contain elements of nuclear fuel and fallout after Chernobyl NPP accident. For the determination of the content of transuranium elements in radioactive aerosols the measurement of the {alpha}-activity of 'hot' particles by SSNTD was used in this work, as well as radiography of fission fragments formed as a result of the reactions (n,f) and ({gamma},f) in the irradiation of aerosol filters by thermal neutrons and high energy gamma quanta. The technique allowed the sizes and alpha-activity of 'hot' particles to be determined without extracting them from the filter, as well as the determination of the uranium content and its enrichment by {sup 235}U, {sup 239}Pu and {sup 241}Pu isotopes. Sensitivity of determination of alpha activity by fission method is 5x10{sup -6} Bq per particle. The software for the system of image analysis was created. It ensured the identification of track clusters on an optical image of the SSNTD surface obtained through a video camera and the determination of size and activity of 'hot' particles00.

  20. α particles and the ''pasta'' phase in nuclear matter

    International Nuclear Information System (INIS)

    Avancini, S. S.; Barros, C. C. Jr.; Menezes, D. P.; Providencia, C.

    2010-01-01

    The effects of the α particles in nuclear matter at low densities are investigated within three different parametrizations of relativistic models at finite temperature. Both homogeneous and inhomogeneous matter (pasta phase) are described for neutral nuclear matter with fixed proton fractions and stellar matter subject to β equilibrium and trapped neutrinos. In homogeneous matter, α particles are present only at densities below 0.02 fm -3 and their presence decreases with increase of the temperature and, for a fixed temperature, the α particle fraction decreases for smaller proton fractions. A repulsive interaction is important to mimic the dissolution of the clusters in homogeneous matter. The effect of the α particles on the pasta structure is very small except close to the critical temperatures and/or proton fractions, when it may still predict a pasta phase while no pasta phase would occur in the absence of light clusters. It is shown that for densities above 0.01 fm 3 the α-particle fraction in the pasta phase is much larger than that in homogeneous matter.

  1. Activation cross-section data for -particle-induced nuclear reactions ...

    Indian Academy of Sciences (India)

    B M ALI

    2018-02-20

    particle-induced nuclear reactions on natural vanadium up to 20 MeV. It should be mentioned that this study represents a part of (a supplement) systematical study of charged particles-induced nuclear reactions. Earlier studies were.

  2. Few body problems in nuclear and particle physics

    International Nuclear Information System (INIS)

    Slobodrian, R.J.; Cujec, B.; Ramavataram, K.

    1975-01-01

    Nucleon-nucleon interactions at all energies, meson-nucleon and meson-deuteron interactions, nuclear bremsstrahlung, on-shell and off-shell interactions, final-state interactions, bound and scattering states, few-body forces, polarization phenomena, short range correlations, quasi-free scattering, composite hadron models, subnucleon structure, multiparticle and coherent production processes, break-up reactions, electrodisintegration, relativistic effects and future resources in nuclear and particle physics are discussed in relation to the state of few-body physics in 1974. (B.F.G.)

  3. Particle physics contribution to the elimination of nuclear waste

    CERN Document Server

    Revol, Jean Pierre Charles

    2000-01-01

    Progress in particle accelerator technology makes it possible to use a proton accelerator to eliminate nuclear waste efficiently. The Energy Amplifier (EA) proposed by C. Rubbia and his group is a subcritical system driven by a proton accelerator. It is particularly attractive for destroying, through fission, transuranic elements produced by present nuclear reactors. The EA could also transform efficiently and at minimal cost long-lived fission fragments using the concept of Adiabatic Resonance Crossing (ARC) recently tested at CERN with the TARC experiment. The ARC concept can be extended to several other application domains (radioactive isotopes production for medicine and industry, neutron research applications, etc.).

  4. Nuclear Reactions in Micro/Nano-Scale Metal Particles

    International Nuclear Information System (INIS)

    Kim, Y. E.

    2013-01-01

    Low-energy nuclear reactions in micro/nano-scale metal particles are described based on the theory of Bose-Einstein condensation nuclear fusion (BECNF). The BECNF theory is based on a single basic assumption capable of explaining the observed LENR phenomena; deuterons in metals undergo Bose-Einstein condensation. The BECNF theory is also a quantitative predictive physical theory. Experimental tests of the basic assumption and theoretical predictions are proposed. Potential application to energy generation by ignition at low temperatures is described. Generalized theory of BECNF is used to carry out theoretical analyses of recently reported experimental results for hydrogen-nickel system. (author)

  5. Nuclear Reactions in Micro/Nano-Scale Metal Particles

    Science.gov (United States)

    Kim, Y. E.

    2013-03-01

    Low-energy nuclear reactions in micro/nano-scale metal particles are described based on the theory of Bose-Einstein condensation nuclear fusion (BECNF). The BECNF theory is based on a single basic assumption capable of explaining the observed LENR phenomena; deuterons in metals undergo Bose-Einstein condensation. The BECNF theory is also a quantitative predictive physical theory. Experimental tests of the basic assumption and theoretical predictions are proposed. Potential application to energy generation by ignition at low temperatures is described. Generalized theory of BECNF is used to carry out theoretical analyses of recently reported experimental results for hydrogen-nickel system.

  6. The way to achieve independence in China's nuclear power development

    International Nuclear Information System (INIS)

    Lian Peisheng

    1986-04-01

    Very much in need of developing nuclear power, China has found the main problem to be shortage of funds, particularly that of foreign currency. The only way to overcome this difficulty is to increase national share to the utmost extent. Since engineering and management of such complex and capital-intensive projects as NPPs has very important bearing on promoting national participation, much emphasis is placed on acquirement of software technology. Technology transfer is therefore sought in light of this need as well as of China's specific conditions. (author)

  7. Domestic nuclear fuels supply: possibility of an independent technology

    International Nuclear Information System (INIS)

    Cirimello, R.O.

    1982-01-01

    After considering the different energy sources, their consumption and their respective periods of exploitation, technological considerations in the nuclear fuel field are made. The main subject is the Domestic Supply Project of Embalse Fuel (CANDU type). The different aspects which had to be developed during the realization of this project still under progress, and which are fundamental for the command of the technology, are described: 1) Qualification of the produced fuel elements: fuel elements' characteristics; the reactors' operating parameters, and the prototype fuel elements' characteristics; 2) Development of materials and/or suppliers: the obtainment of UO 2 and its physical properties are considered, as well as those of Zircaloy-4, the development of suppliers and the respective developments for the obtainment of materials such as beryllium, helium and colloidal graphite; 3) Processes development; the following processes are studied and defined: UO 2 pellets fabrication with UO 2 granulated powder; beryllium coating under vaccum; and induction brazing of bearing pads and spacers, end cap and end plate resistance welding and stamping of Zircaloy components, graphite-coating of cladding's internal face; 4) Development of special production equipments; automatic equipment for end cap-to-cladding resistance welding among others. The need for a specific program of quality assurance for nuclear fuels supply is emphasized and the basic criteria are established. The IAEA's quality asssurance requirements are also analyzed. (M.E.L.) [es

  8. Improved moulding material for addition to nuclear fuel particles to produce nuclear fuel elements

    International Nuclear Information System (INIS)

    Miertschin, G.N.; Leary, D.F.

    1976-01-01

    A suggestion is made to improve the moulding materials used to produce carbon-contained nuclear fuel particles by a coke-reducing added substance. The nuclear fuel particles are meant for the formation of fuel elements for gas-cooled high-temperature nuclear reactors. The moulding materials are above all for the formation of coated particles which are burnt in situ in nuclear fuel element chambers out of 'green' nuclear fuel bodies. The added substance improves the shape stability of the particles forming and prevents a stiding or bridge formation between the particles or with the surrounding walls. The following are named as added substances: 1) Polystyrene and styrene-butadiene-Co polymers (mol. wt. between 5oo and 1,000,000), 2) aromatic compounds (mol. wt. 75 to 300), 3) saturated hydrocarbon polymers (mol. wt. 5,000 to 1,000,000). Additional release agents further improve the properties in the same direction (e.g. alcohols, fatty acids, amines). (orig.) [de

  9. Nuclear and particle physics, astrophysics and cosmology (NPAC) capability review

    Energy Technology Data Exchange (ETDEWEB)

    Redondo, Antonio [Los Alamos National Laboratory

    2010-01-01

    The present document represents a summary self-assessment of the status of the Nuclear and Particle Physics, Astrophysics and Cosmology (NPAC) capability across Los Alamos National Laboratory (LANL). For the purpose of this review, we have divided the capability into four theme areas: Nuclear Physics, Particle Physics, Astrophysics and Cosmology, and Applied Physics. For each theme area we have given a general but brief description of the activities under the area, a list of the Laboratory divisions involved in the work, connections to the goals and mission of the Laboratory, a brief description of progress over the last three years, our opinion of the overall status of the theme area, and challenges and issues.

  10. The weak interaction in nuclear, particle and astrophysics

    International Nuclear Information System (INIS)

    Grotz, K.; Klapdor, H.V.

    1989-01-01

    This book is an introduction to the concepts of weak interactions and their importance and consequences for nuclear physics, particle physics, neutrino physics, astrophysics and cosmology. After a general introduction to elementary particles and interactions the Fermi theory of weak interactions is described together with its connection with nuclear structure and beta decay including the double beta decay. Then, after a general description of gauge theories the Weinberg-Salam theory of the electroweak interactions is introduced. Thereafter the weak interactions are considered in the framework of grand unification. Then the physics of neutrinos is discussed. Thereafter connections of weak interactions with astrophysics are considered with special regards to the gravitational collapse and the synthesis of heavy elements in the r-process. Finally, the connections of grand unified theories and cosmology are considered. (HSI) With 141 figs., 39 tabs

  11. Multiparticle production in particle and nuclear collisions, 2

    International Nuclear Information System (INIS)

    Kanki, Takeshi; Kinoshita, Kisei; Sumiyoshi, Hiroyuki; Takagi, Fujio.

    1990-01-01

    Multiparticle dynamics is related to many branches of particle and nuclear physics. This book provides a comprehensive review which covers the whole domain of multiparticle dynamics. The review consists of five chapters. Chapter D, which is the first chapter of this volume, is titled 'Mechanism of Fragmentation' and contains six sections dealing with 'parton densities inside hadrons', 'hadron fragmentation and quark picture', 'recombination type models', 'quark fragmentation models in soft interaction', 'diquark and its fragmentation' and 'fragmentation in string models'. Chapter E 'Diffractive Production of Hadrons' discusses 'diffractive inelastic processes of composite particles', 'diffractive processes and triple-pomeron coupling', 'properties of diffractive inelastic final states', and 'nature of pomeron'. Chapter F 'Unified Descriptions' focuses on 'general chain picture', 'dual parton model', 'Monte Carlo simulations' and 'unification of hard and soft interactions'. Chapter G, titled 'Multiparticle Production in Hadron-Nucleus Collisions and Other Nuclear Processes' and contains 11 sections. Chapter H presents conclusions. (N.K.)

  12. Nuclear reactions induced by high-energy alpha particles

    Science.gov (United States)

    Shen, B. S. P.

    1974-01-01

    Experimental and theoretical studies of nuclear reactions induced by high energy protons and heavier ions are included. Fundamental data needed in the shielding, dosimetry, and radiobiology of high energy particles produced by accelerators were generated, along with data on cosmic ray interaction with matter. The mechanism of high energy nucleon-nucleus reactions is also examined, especially for light target nuclei of mass number comparable to that of biological tissue.

  13. Automatic particle-size analysis of HTGR nuclear fuel microspheres

    International Nuclear Information System (INIS)

    Mack, J.E.

    1977-01-01

    An automatic particle-size analyzer (PSA) has been developed at ORNL for measuring and counting samples of nuclear fuel microspheres in the diameter range of 300 to 1000 μm at rates in excess of 2000 particles per minute, requiring no sample preparation. A light blockage technique is used in conjunction with a particle singularizer. Each particle in the sample is sized, and the information is accumulated by a multi-channel pulse height analyzer. The data are then transferred automatically to a computer for calculation of mean diameter, standard deviation, kurtosis, and skewness of the distribution. Entering the sample weight and pre-coating data permits calculation of particle density and the mean coating thickness and density. Following this nondestructive analysis, the sample is collected and returned to the process line or used for further analysis. The device has potential as an on-line quality control device in processes dealing with spherical or near-spherical particles where rapid analysis is required for process control

  14. Bibliography of integral charged-particle nuclear data

    International Nuclear Information System (INIS)

    Burrows, T.W.; Wyant, G.

    1981-03-01

    This publication is the first supplement to the archival edition of the National Nuclear Data Center's charged-particle bibliography. This supplement contains citations to all references scanned since March 15, 1980, and all corrections and additions to previous citations, and indexes all data received in the international exchanged format (EXFOR). The primary goal of the bibliography has been to satisfy the need expressed by the Nuclear Reaction Data Center Network for a concise and comprehensive bibliography of integral charged-particle cross section data and to provide an index of data exchanged among the members. As a result of a recommendation by the recent Workshop on Intense High Energy Neutron Source and Their Characteristics, we have also undertaken to expand the coverage of charged-particle-induced neutron-source reactions to include differential data. This supplement is divided into two sections, References and Isotope Production. The References section contains all references satisfying the criteria noted. The Isotope Production section contains an abbreviated reference line for all entries which contain information on a definite residual nucleus, on particle production, or on mass, charge, or isotopic distributions. Entries in the References section are sequentially numbered. These sequence numbers serve as a link between the two sections

  15. Hardened over-coating fuel particle and manufacture of nuclear fuel using its fuel particle

    International Nuclear Information System (INIS)

    Yoshimuda, Hideharu.

    1990-01-01

    Coated-fuel particles comprise a coating layer formed by coating ceramics such as silicon carbide or zirconium carbide and carbons, etc. to a fuel core made of nuclear fuel materials. The fuel core generally includes oxide particles such as uranium, thorium and plutonium, having 400 to 600 μm of average grain size. The average grain size of the coated-fuel particle is usually from 800 to 900 μm. The thickness of the coating layer is usually from 150 to 250 μm. Matrix material comprising a powdery graphite and a thermosetting resin such as phenol resin, etc. is overcoated to the surface of the coated-fuel particle and hardened under heating to form a hardened overcoating layer to the coated-fuel particle. If such coated-fuel particles are used, cracks, etc. are less caused to the coating layer of the coated-fuel particles upon production, thereby enabling to prevent the damages to the coating layer. (T.M.)

  16. Heavy particle scattering by atomic and nuclear systems

    International Nuclear Information System (INIS)

    Lazauskas, R.

    2003-10-01

    In this thesis quantum mechanical non-relativistic few-body problem is discussed. Basing on fundamentals ideas from Faddeev and Yakubovski three and four body equations are formulated and solved for fermionic atomic and nuclear systems. Former equations are modified to include long range interactions. Original results for nuclear and molecular physics were obtained: -) positively charged particle scattering on hydrogen atoms was considered; predictions for π + → H, μ + → H and p + → H scattering lengths were given. Existence of an unknown, very weakly bound H + 2 bound state was predicted. -) Motivated by the possible observation of bound four neutron structure at GANIL we have studied compatibility of such an existence within the current nuclear interaction models. -) 4 nucleon scattering at low energies was investigated. Results for n → 3 H, p → 3 H and p → 3 He systems were compared with the experimental data. Validity of realistic nucleon-nucleon interaction models is questioned. (author)

  17. Independence in regulatory decision making - INSAG-17. A report by the International Nuclear Safety Advisory Group

    International Nuclear Information System (INIS)

    2003-01-01

    This report is intended to promote a common understanding among legislators and other political decision makers, nuclear safety regulators and licensees of the concept of independence in regulatory decision making and how to achieve it. Other interest groups, such as non-governmental organizations and members of the public interested in the regulation of nuclear safety, may also find the report useful. The principles concerning the independence of regulatory organizations are developed and discussed in publications in the IAEA's Safety Standards Series. Although the principles relating to protecting the independence of the regulatory body provide the necessary basis for independence in regulatory decision making, there are additional factors and features that require attention to ensure independence in the decision making by the regulatory body. This INSAG report highlights and discusses a number of such factors and features

  18. Charged particle spectroscopy with solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Hunyadi, I.; Somogyi, G.

    1984-01-01

    Some of earlier and recent methods for differentiation of charged particles according to their energy, based on the use of polymeric etch-track detectors (CN, CA, PC and CR-39) are outlined. The principle of three track methods suitable for nuclear spectroscopy is discussed. These are based on the analysis of the diameter, surface size and shape of etch-track 'cones' produced by charged particles in polymers, after using shorter or longer chemical etching processes. Examples are presented from the results of the last decade in ATOMKI, Debrecen, Hungary, concerning the application of nuclear track spectroscopy to different low-energy nuclear reaction studies, angular distribution and excitation function measurements. These involve the study of (d,α) reaction on sup(14)N, sup(19)F and sup(27)Al nuclei, (sup(3)He,α) reactions on sup(15)N, (p,α) reaction on sup(27)Al and the process sup(12)C(sup(12)C, sup(8)Be)sup(16)O. (author)

  19. Particle swarm as optimization tool in complex nuclear engineering problems

    International Nuclear Information System (INIS)

    Medeiros, Jose Antonio Carlos Canedo

    2005-06-01

    Due to its low computational cost, gradient-based search techniques associated to linear programming techniques are being used as optimization tools. These techniques, however, when applied to multimodal search spaces, can lead to local optima. When finding solutions for complex multimodal domains, random search techniques are being used with great efficacy. In this work we exploit the swarm optimization algorithm search power capacity as an optimization tool for the solution of complex high dimension and multimodal search spaces of nuclear problems. Due to its easy and natural representation of high dimension domains, the particle swarm optimization was applied with success for the solution of complex nuclear problems showing its efficacy in the search of solutions in high dimension and complex multimodal spaces. In one of these applications it enabled a natural and trivial solution in a way not obtained with other methods confirming the validity of its application. (author)

  20. UNITED STATES: Particle and nuclear astrophysicists look to the future

    International Nuclear Information System (INIS)

    Ayres, David; Kolb, Edward W.

    1994-01-01

    While many high-energy physicists are planning giant colliding beams machines as the vessels to sail beyond the familiar waters of the Standard Model, others are testing alternate conveyances to explore the most fundamental issues of particle physics. Studies of proton decay, neutrino masses and oscillations, dark matter, high-energy astronomy, microwave background fluctuations, large-scale structure, and the physics of the early Universe could move the field far from the Standard Model shore. Just as zoologists and geologists once explored new lands together, high-energy physicists have been joined by nuclear physicists and astrophysicists who are interested in the experiments because of the relevance to their own disciplines

  1. UNITED STATES: Particle and nuclear astrophysicists look to the future

    Energy Technology Data Exchange (ETDEWEB)

    Ayres, David [Argonne (United States); Kolb, Edward W. [FERMILAB (United States); University of Chicago (United States)

    1994-12-15

    While many high-energy physicists are planning giant colliding beams machines as the vessels to sail beyond the familiar waters of the Standard Model, others are testing alternate conveyances to explore the most fundamental issues of particle physics. Studies of proton decay, neutrino masses and oscillations, dark matter, high-energy astronomy, microwave background fluctuations, large-scale structure, and the physics of the early Universe could move the field far from the Standard Model shore. Just as zoologists and geologists once explored new lands together, high-energy physicists have been joined by nuclear physicists and astrophysicists who are interested in the experiments because of the relevance to their own disciplines.

  2. Real stabilization method for nuclear single-particle resonances

    International Nuclear Information System (INIS)

    Zhang Li; Zhou Shangui; Meng Jie; Zhao Enguang

    2008-01-01

    We develop the real stabilization method within the framework of the relativistic mean-field (RMF) model. With the self-consistent nuclear potentials from the RMF model, the real stabilization method is used to study single-particle resonant states in spherical nuclei. As examples, the energies, widths, and wave functions of low-lying neutron resonant states in 120 Sn are obtained. These results are compared with those from the scattering phase-shift method and the analytic continuation in the coupling constant approach and satisfactory agreements are found

  3. Heavy particle decay studies using different versions of nuclear potentials

    Science.gov (United States)

    Santhosh, K. P.; Sukumaran, Indu

    2017-10-01

    The heavy particle decay from 212-240Pa , 219-245Np , 228-246Pu , 230-249Am , and 232-252Cm leading to doubly magic 208Pb and its neighboring nuclei have been studied using fourteen versions of nuclear potentials. The study has shown that the barrier penetrability as well as the decay half-lives are found to vary with the nuclear potential used. The investigated decay events of the emission of the clusters 22Ne , 24Ne , 26Mg , 28Mg , 32Si and 33Si are not experimentally detected yet but may be detectable in the future. As most of the half-lives predicted are found to lie within the experimental upper limit, T 1/2 parents with varying slopes and intercepts. Also, it is to be noted that the linearity of the GN plots is unaltered using different nuclear potentials. The universal curve studied ( log10 T 1/2 vs. -ln P for various clusters emitted from various parents shows a linear behavior with the same slope and intercept irrespective of the nuclear potential used.

  4. Regulatory challenges for independent organization and licensing procedures for Egypt first nuclear power program

    International Nuclear Information System (INIS)

    Elsheikh, B.M.

    2012-01-01

    In March 2010 the Government of Egypt issued an Ordinance creating an independent regulatory body the Egypt Nuclear and Radiological Regulatory Authority (NRRA) reporting directly to the Prime Minister and responsible for matters dealing with protection of the radiation worker, public and environment from the harmful effects of ionizing radiation. A little more than 2 years have elapsed since this date. Some of the challenges faced by NRRA to its regulatory independence are given below. This paper will discuss the major challenges relating to Egyptian nuclear power program and specially the regulatory effectiveness and licensing procedures compared to international comparison.

  5. The excitation of an independent-particle gas by a time dependent potential well

    Directory of Open Access Journals (Sweden)

    J. P. Błocki

    2010-09-01

    Full Text Available The order-to-chaos transition in the dynamics of independent classical particles gas was studied by means of the numerical simulations. The excitation of the gas for containers whose surfaces are rippled according to Legendre polynomials P2 , P3, P4 , P5 , P6 was followed for ten periods of oscillations. Spheroidal deformations were also considered. Poincare sections and Lyapunov exponents have been calculated showing different degrees of chaoticity depending on the shape and amplitude of oscillations. For 2 P polynomial the reaction of a gas to the periodic container deformation is mostly elastic as 2 P deformation especially for not very big deformations is almost like an integrable spheroid. For other polynomials the situation is more or less chaotic with a chaoticity increasing with the increasing order of the polynomial.

  6. The uses of isospin in early nuclear and particle physics

    Science.gov (United States)

    Borrelli, Arianna

    2017-11-01

    This paper reconstructs the early history of isospin up to and including its employment in 1951sbnd 52 to conceptualize high-energy pion-proton scattering. Studying the history of isospin serves as an entry point for investigating the interplay of theoretical and experimental practices in early nuclear and particle physics, showing the complexity of processes of knowledge construction which have often been presented as straightforward both in physicists' recollections and in the historiography of science. The story of isospin has often been told in terms of the discovery of the first ;intrinsic property; of elementary particles, but I will argue that the isospin formalism emerged and was further developed because it proved to be a useful tool to match theory and experiment within the steadily broadening field of high-energy (nuclear) physics. Isospin was variously appropriated and adapted in the course of two decades, before eventually the physical-mathematical implications of its uses started being spelled out. The case study also highlights some interesting features of high-energy physics around 1950: the contribution to post-war research of theoretical methods developed before and during the war, the role of young theoretical post-docs in mediating between theorists and experimenters, and the importance of traditional formalisms such as those of spin and angular momentum as a template both for formalizing and conceptualizing experimental results.

  7. UCLA Particle and Nuclear Physics Research Group, 1993 progress report

    International Nuclear Information System (INIS)

    Nefkens, B.M.K.; Clajus, M.; Price, J.W.; Tippens, W.B.; White, D.B.

    1993-09-01

    The research programs of the UCLA Particle and Nuclear Physics Research Group, the research objectives, results of experiments, the continuing activities and new initiatives are presented. The primary goal of the research is to test the symmetries and invariances of particle/nuclear physics with special emphasis on investigating charge symmetry, isospin invariance, charge conjugation, and CP. Another important part of our work is baryon spectroscopy, which is the determination of the properties (mass, width, decay modes, etc.) of particles and resonances. We also measure some basic properties of light nuclei, for example the hadronic radii of 3 H and 3 He. Special attention is given to the eta meson, its production using photons, electrons, π ± , and protons, and its rare and not-so-rare decays. In Section 1, the physics motivation of our research is outlined. Section 2 provides a summary of the research projects. The status of each program is given in Section 3. We discuss the various experimental techniques used, the results obtained, and we outline the plans for the continuing and the new research. Details are presented of new research that is made possible by the use of the Crystal Ball Detector, a highly segmented NaI calorimeter and spectrometer with nearly 4π acceptance (it was built and used at SLAC and is to be moved to BNL). The appendix contains an update of the bibliography, conference participation, and group memos; it also indicates our share in the organization of conferences, and gives a listing of the colloquia and seminars presented by us

  8. National Institute of Nuclear and Particle Physics - IN2P3. 2001-2003 activity report

    International Nuclear Information System (INIS)

    Spiro, Michel; Armand, Dominique

    2005-12-01

    The CNRS National Institute of Nuclear and Particle Physics (IN2P3) acts as national leader and coordinator in the fields of nuclear, particle and astro-particle physics, technological advances and their related applications, especially in the health and energy sectors. This research aims to explore particle and nuclear physics, fundamental interactions, and the links between the infinitely small and the infinitely large. Scientific fields include: Particle physics and hadronic physics, Nuclear physics, Astro-particles and cosmology, Neutrinos, Instrumentation, Computing and data, Research and development of accelerators, Back-end of the nuclear fuel cycle and nuclear energy, Medical applications. This document is IN2P3's activity report for the 2001-2003 period. It presents the strategic priorities of the Institute, the highlights and projects of the period

  9. Rationale of beings: Recent developments in particle, nuclear and general physics

    International Nuclear Information System (INIS)

    Ishikawa, K.; Kawazoc, Y.; Matsuzaki, H.; Takahashi, K.

    1986-01-01

    This book presents papers on particle physics and nuclear physics. The chapters are on gravity, particles and fields, quantum theories, field theories, nuclei and atoms and general physics. Recent developments in various fields of physics in general are discussed

  10. Charged-particle transfer reactions and nuclear astrophysics problems

    International Nuclear Information System (INIS)

    Artemov, S.V.; Yarmukhamedov, R.; Yuldashev, B.S.; Burtebaev, N.; Duysebaev, A.; Kadyrzhanov, K.K.

    2002-01-01

    In the report a review of the recent results of calculation of the astrophysical S-factors S(E) for the D(α, γ) 6 Li, 3 He(α, γ) 7 Be, 7 Be(p, γ) 8 Be, 12,13 C(p, γ) 13, 14 N and 12 C(p,γ) 16 O* reactions at extremely low energies E, including value E=0 , performed within the framework of a new method taking into account the additional information about the nuclear vertex constant (Nc) (or the respective asymptotic normalization coefficient) are presented. The required values of Nc can be obtained from an analysis of measured differential cross-sections of proton and α-particle transfer reactions (for example A( 3 He,d)B, 6 Li(d, 6 Li)d, 6 Li(α, 6 Li)α, 12 C( 6 Li, d) 16 O* etc.). A comparative analysis between the results obtained by different authors is also done. Taking into account an important role of the NVC's values for the nuclear astrophysical A(p, γ)B and A(α, γ)B reactions, a possibility of obtaining the reliable NVC values for the virtual decay B→A+p and B→A+α from the analysis of differential cross sections both sub- and above-barrier A( 3 He, d) and A( 6,7 Li, 2,3 H)B reactions is discussed in detail. In this line the use the isochronous cyclotron U-150 M, the 'DC-60' heavy ion machine and electrostatic charge-exchanging accelerator UKP-2-1 of Institute of Nuclear Physics of National Nuclear Center of the Republic of Kazakhstan for carrying out the needed experiments is considered and the possibility of the obtained data application for the astrophysical interest is also discussed

  11. Fundamental design bases for independent core cooling in Swedish nuclear power reactors

    International Nuclear Information System (INIS)

    Jelinek, Tomas

    2015-01-01

    New regulations on design and construction of nuclear power plants came into force in 2005. The need of an independent core cooling system and if the regulations should include such a requirement was discussed. The Swedish Radiation Safety authority (SSM) decided to not include such a requirement because of open questions about the water balance and started to investigate the consequences of an independent core cooling system. The investigation is now finished and SSM is also looking at the lessons learned from the accident in Fukushima 2011. One of the most important measures in the Swedish national action plan is the implementation of an independent core cooling function for all Swedish power plants. SSM has investigated the basic design criteria for such a function where some important questions are the level of defence in depth and the acceptance criteria. There is also a question about independence between the levels of defence in depth that SSM have included in the criteria. Another issue that has to be taken into account is the complexity of the system and the need of automation where independence and simplicity are very strong criteria. In the beginning of 2014 a memorandum was finalized regarding fundamental design bases for independent core cooling in Swedish nuclear power reactors. A decision based on this memorandum with an implementation plan will be made in the first half of 2014. Sweden is also investigating the possibility to have armed personnel on site, which is not allowed currently. The result from the investigation will have impact on the possibility to use mobile equipment and the level of protection of permanent equipment. In this paper, SSM will present the memorandum for design bases for independent core cooling in Swedish nuclear power reactors that was finalized in March 20147 that also describe SSM's position regarding independence and automation of the independent core cooling function. This memorandum describes the Swedish

  12. Annual review of nuclear and particle science. Vol. 52

    International Nuclear Information System (INIS)

    Quigg, C.

    2002-01-01

    The 2002 volume of the ''Annual Review of Nuclear and Particle Science'' ranges from the applied to the speculative, from the accomplished to the inchoate, bearing witness to the vitality and diversity of subatomic physics. Milla Baldo Ceolin's prefatory chapter , ''The Discreet Charm of the Nuclear Emulsion Era,'' takes us back to the rebirth of particle physics in Europe after World War II through international emulsion collaborations that revealed wonders unimagined. Gaisser and Honda detail progress toward understanding the flux of atmospheric neutrinos, which is crucial for interpreting evidence for neutrino oscillations and searching for extraterrestrial neutrino sources. Elliott and Vogel's status report on double beta decay explores the sensitivity frontier and the prospects for testing the notion that the neutrino is its own antiparticle. Kado and Tully take stock of searches for electroweak theory's Higgs boson at CERN's Large Electron-Positron collider. Lee and Redwine draw lessons from three decades' exploration of pion-nucleus interactions at meson factories. Bedaque and van Kolck review recent progress in effective field theories that permit systematic treatment of few-nucleon systems. El-Khadra and Luke describe the ways in which Quantum Chromodynamics makes possible a precise determination of the b-quark mass. Harrison, Peggs, and Roser report on Brookhaven National Laboratory's Relativistic Heavy-Ion Collider, which explores new realms of collisions among heavy nuclei. Gomez-Cadenas and Harris introduce the scientific motivations and technical challenges of neutrino factories based on muon storage rings. The study of biological function through positron-emission tomography is a burgeoning application of antimatter. PET's history, practice, and promise are presented by Phelps. Michael Faraday's words, ''Nothing is too wonderful to be true,'' and ''Experiment is the best test,'' are especially apt for the delicious possibility that spacetime extends

  13. Future directions in particle and nuclear physics at multi-GeV hadron beam facilities

    Energy Technology Data Exchange (ETDEWEB)

    Geesaman, D.F. [Argonne National Lab., IL (United States)] [ed.

    1993-11-01

    This report contains papers on the following topics in particle and nuclear physics: hadron dynamics; lepton physics; spin physics; hadron and nuclear spectroscopy; hadronic weak interactions; and Eta physics. These papers have been indexed separately elsewhere.

  14. Future directions in particle and nuclear physics at multi-GeV hadron beam facilities

    International Nuclear Information System (INIS)

    Geesaman, D.F.

    1993-01-01

    This report contains papers on the following topics in particle and nuclear physics: hadron dynamics; lepton physics; spin physics; hadron and nuclear spectroscopy; hadronic weak interactions; and Eta physics. These papers have been indexed separately elsewhere

  15. Blind intercomparison of nuclear models for predicting charged particle emission

    International Nuclear Information System (INIS)

    Shibata, K.; Cierjacks, S.

    1994-01-01

    Neutron activation data are important for dosimetry, radiation-damage and production of long-lived activities. For fusion energy applications, it is required to develop 'low-activation materials' from the viewpoints of safety, maintenance and waste disposal. Existing evaluated activation cross-section libraries are to a large extent based on nuclear-model calculations. The former Nuclear Energy Agency Nuclear Data Committee, NEANDC, (presently replaced by the NEA Nuclear Science Committee) organized the working group on activation cross sections. The first meeting of the group was held in 1989, and it was then agreed that a blind intercomparison of nuclear-model calculations should be undertaken in order to test the predictive power of the theoretical calculations. As a first stage the working group selected the reactions 60g Co(n,p) 60 Fe and 60m Co(n,p) 60 Fe, for which no experimental data were available, in the energy range from 1 to 20 MeV. The preliminary results compiled at the NEA Data Bank were sent to each participant and a meeting was held during the International Conference on Nuclear Data for Science and Technology in Julich 1991 to discuss the results. Following the outcome of the discussion in Julich, it was decided to extend this intercomparison. In the second-stage calculation, the same optical-model parameters were employed for neutrons, protons and α-particles, i.e., V = 50 MeV, W = 10 MeV, r = 1.25 fm and a = 0.6 fm with the Woods-Saxon volume-type form factors. No spin-orbit interaction was considered. Concerning the level density, the Fermi gas model with a = A/8 MeV -1 was assumed without pairing corrections. Moreover, gamma-ray competition was neglected to simplify the calculation. This report describes the final results of the blind comparison. Section 2 deals with a survey of the received contributions. The final results are graphically presented in section 3. 67 figs., 1 tab., 12 refs

  16. 4-D single particle tracking of synthetic and proteinaceous microspheres reveals preferential movement of nuclear particles along chromatin - poor tracks.

    Science.gov (United States)

    Bacher, Christian P; Reichenzeller, Michaela; Athale, Chaitanya; Herrmann, Harald; Eils, Roland

    2004-11-23

    The dynamics of nuclear organization, nuclear bodies and RNPs in particular has been the focus of many studies. To understand their function, knowledge of their spatial nuclear position and temporal translocation is essential. Typically, such studies generate a wealth of data that require novel methods in image analysis and computational tools to quantitatively track particle movement on the background of moving cells and shape changing nuclei. We developed a novel 4-D image processing platform (TIKAL) for the work with laser scanning and wide field microscopes. TIKAL provides a registration software for correcting global movements and local deformations of cells as well as 2-D and 3-D tracking software. With this new tool, we studied the dynamics of two different types of nuclear particles, namely nuclear bodies made from GFP-NLS-vimentin and microinjected 0.1 mum - wide polystyrene beads, by live cell time-lapse microscopy combined with single particle tracking and mobility analysis. We now provide a tool for the automatic 3-D analysis of particle movement in parallel with the acquisition of chromatin density data. Kinetic analysis revealed 4 modes of movement: confined obstructed, normal diffusion and directed motion. Particle tracking on the background of stained chromatin revealed that particle movement is directly related to local reorganization of chromatin. Further a direct comparison of particle movement in the nucleoplasm and the cytoplasm exhibited an entirely different kinetic behaviour of vimentin particles in both compartments. The kinetics of nuclear particles were slightly affected by depletion of ATP and significantly disturbed by disruption of actin and microtubule networks. Moreover, the hydration state of the nucleus had a strong impact on the mobility of nuclear bodies since both normal diffusion and directed motion were entirely abolished when cells were challenged with 0.6 M sorbitol. This effect correlated with the compaction of chromatin

  17. Study of Particle Production and Nuclear Fragmentation in Relativistic Heavy-Ion Collisions in Nuclear Emulsions

    CERN Multimedia

    2002-01-01

    % EMU11 \\\\ \\\\ We propose to use nuclear emulsions for the study of nuclear collisions of $^{207}$Pb, $^{197}$Au, and any other heavy-ion beams when they are available. We have, in the past, used $^{32}$S at 200A~GeV and $^{16}$O at 200A and 60A~GeV from CERN (Experiment EMU08) and at present the analysis is going on with $^{28}$Si beam from BNL at 14.5A~GeV. It will be important to compare the previous and the present investigations with the new $^{207}$Pb beam at 60-160A~GeV. We want to measure in nuclear emulsion, on an event by event basis, shower particle multiplicity, pseudorapidity density and density fluctuations of charged particles, charge multiplicity and angular distributions of projectile fragments, production and interaction cross-sections of heavily ionizing particles emitted from the target fragmentation. Special emphasis will be placed on the analysis of events produced in the central collisions which are selected on the basis of low energy fragments emitted from the target excitation. It woul...

  18. Proceedings of the Fourth Conference on Nuclear and Particle Physics (NUPPAC-2003)

    Energy Technology Data Exchange (ETDEWEB)

    Comsan, M N.H.; Hanna, K M [Nuclear Research Center, Atomic Energy Authority, Cairo (Egypt)

    2004-08-15

    The publication's has been set up as a book of the conference of nuclear and particle physics, it consists of the following chapters (1) high energy physics; (2) nuclear scattering and reaction; (3) nuclear models and spectroscopy; (3) neutron and reactor physics; (4) applied nuclear physics; (5) Detectors and Instrumentations; (6) computer codes and stimulation; (7) radiation measurement and dosimetry; (8) selected topics.

  19. Proceedings of the Third Nuclear and Particle Physics Conference (NUPPAC-2001)

    Energy Technology Data Exchange (ETDEWEB)

    Comsan, M N.H.; Hanna, K M [Egyptian Nuclear Physics Association, Cairo (Egypt)

    2002-09-15

    The publication's has been set up as a book of the conference of nuclear and particle physics, it consists of the following chapters (1) high energy physics; (2) nuclear scattering and reaction; (3) nuclear models and spectroscopy; (3) neutron and reactor physics; (4) applied nuclear physics; (5) computer codes; (6) selected topics; (7) radiation sciences.

  20. Proceeding of the seventh Nuclear and Particle Physics Conference (NUPPAC-2009)

    International Nuclear Information System (INIS)

    Comsan, M.N.H.

    2009-11-01

    The publication has been set up as proceedings of the Nuclear and Particle physics conference. the conference consists Nuclear Scattering and Reactions; High Energy Physics; Nuclear Structure and Spectroscopy; Neutron and Reactor Physics; Relativistic and Quantum Physics; Modeling, Codes and Simulation; Nuclear Analytical Techniques; Accelerator and Reactor Utilization; Detectors and Instrumentation; Radiation and Radioactivity. This conference consists of 662 p., figs., tabs., refs.

  1. Proceedings of the Fourth Conference on Nuclear and Particle Physics (NUPPAC-2003)

    International Nuclear Information System (INIS)

    Comsan, M.N.H.; Hanna, K.M.

    2004-08-01

    The publication's has been set up as a book of the conference of nuclear and particle physics, it consists of the following chapters (1) high energy physics; (2) nuclear scattering and reaction; (3) nuclear models and spectroscopy; (3) neutron and reactor physics; (4) applied nuclear physics; (5) Detectors and Instrumentations; (6) computer codes and stimulation; (7) radiation measurement and dosimetry; (8) selected topics

  2. Proceeding of the Sixth Nuclear and Particle Physics Conference (NUPPAC-2007)

    International Nuclear Information System (INIS)

    2008-11-01

    The publication has been set up as proceedings of the Nuclear and Particle Physics conference, the conference contains of the following subjects: High Energy Physics; Nuclear Scattering and Reactions; Nuclear Structure and Spectroscopy; Nuclear and Reactor Physics; Relativistic and Quantum Physics; Plasma and magneto hydro Dynamics; Computation and Simulation and Radiation Measurement and Dosimetry. This conference consists of 642 pages., figs., tabs., refs

  3. Proceedings of the Second Conference on Nuclear and Particle Physics (NUPPAC-99)

    Energy Technology Data Exchange (ETDEWEB)

    Comsan, M N.H.; Hanna, K M [Nuclear Research Center, Atomic Energy Authority, Cairo (Egypt)

    2000-11-15

    The publication's has been set up as a book of the conference of nuclear and particle physics, it consists of the following chapters (1) high energy physics; (2) nuclear scattering and reaction; (3) nuclear models and spectroscopy; (3) neutron and reactor physics; (4) plasma and fusion physics; (5) applied nuclear physics; (6) related topics.

  4. Proceedings of the Second Conference on Nuclear and Particle Physics (NUPPAC-99)

    International Nuclear Information System (INIS)

    Comsan, M.N.H.; Hanna, K.M.

    2000-11-01

    The publication's has been set up as a book of the conference of nuclear and particle physics, it consists of the following chapters (1) high energy physics; (2) nuclear scattering and reaction; (3) nuclear models and spectroscopy; (3) neutron and reactor physics; (4) plasma and fusion physics; (5) applied nuclear physics; (6) related topics

  5. Proceedings of the Third Nuclear and Particle Physics Conference (NUPPAC-2001)

    International Nuclear Information System (INIS)

    Comsan, M.N.H.; Hanna, K.M.

    2002-09-01

    The publication's has been set up as a book of the conference of nuclear and particle physics, it consists of the following chapters (1) high energy physics; (2) nuclear scattering and reaction; (3) nuclear models and spectroscopy; (3) neutron and reactor physics; (4) applied nuclear physics; (5) computer codes; (6) selected topics; (7) radiation sciences

  6. Investigation of Rare Particle Production in High Energy Nuclear Collisions

    International Nuclear Information System (INIS)

    Crawford, Henry J.; Engelage, Jon M.

    1999-01-01

    Our program is an investigation of the hadronization process through measurement of rare particle production in high energy nuclear interactions. Such collisions of heavy nuclei provide an environment similar in energy density to the conditions in the Big Bang. We are currently involved in two major experiments to study this environment, E896 at the AGS and STAR at RHIC. We have completed our physics running of E896, a search for the H dibaryon and measurement of hyperon production in AuAu collisions, and are in the process of analyzing the data. We have produced the electronics and software for the STAR trigger and will begin to use these tools to search for anti-nuclei and strange hadrons when RHIC turns on later this year

  7. 76 FR 40403 - R.E. Ginna Nuclear Power Plant, LLC, R.E. Ginna Nuclear Power Plant, R.E. Ginna Independent Spent...

    Science.gov (United States)

    2011-07-08

    ... NUCLEAR REGULATORY COMMISSION [Docket No. 50-244; Docket No. 72-67] R.E. Ginna Nuclear Power Plant, LLC, R.E. Ginna Nuclear Power Plant, R.E. Ginna Independent Spent Fuel Storage Installation; Notice of... Facility Operating License No. DPR-18, for the R.E. Ginna Nuclear Power Plant (Ginna), currently held by R...

  8. A simulator-independent optimization tool based on genetic algorithm applied to nuclear reactor design

    International Nuclear Information System (INIS)

    Abreu Pereira, Claudio Marcio Nascimento do; Schirru, Roberto; Martinez, Aquilino Senra

    1999-01-01

    Here is presented an engineering optimization tool based on a genetic algorithm, implemented according to the method proposed in recent work that has demonstrated the feasibility of the use of this technique in nuclear reactor core designs. The tool is simulator-independent in the sense that it can be customized to use most of the simulators which have the input parameters read from formatted text files and the outputs also written from a text file. As the nuclear reactor simulators generally use such kind of interface, the proposed tool plays an important role in nuclear reactor designs. Research reactors may often use non-conventional design approaches, causing different situations that may lead the nuclear engineer to face new optimization problems. In this case, a good optimization technique, together with its customizing facility and a friendly man-machine interface could be very interesting. Here, the tool is described and some advantages are outlined. (author)

  9. ESCRT-independent budding of HIV-1 gag virus-like particles from Saccharomyces cerevisiae spheroplasts.

    Directory of Open Access Journals (Sweden)

    Andrew P Norgan

    Full Text Available Heterologous expression of HIV-1 Gag in a variety of host cells results in its packaging into virus-like particles (VLPs that are subsequently released into the extracellular milieu. This phenomenon represents a useful tool for probing cellular factors required for viral budding and has contributed to the discovery of roles for ubiquitin ligases and the endosomal sorting complexes required for transport (ESCRTs in viral budding. These factors are highly conserved throughout eukaryotes and have been studied extensively in the yeast Saccharomyces cerevisiae, a model eukaryote previously utilized as a host for the production of VLPs. We used heterologous expression of HIV Gag in yeast spheroplasts to examine the role of ESCRTs and associated factors (Rsp5, a HECT ubiquitin ligase of the Nedd4 family; Bro1, a homolog of Alix; and Vps4, the AAA-ATPase required for ESCRT function in all contexts/organisms investigated in the generation of VLPs. Our data reveal: 1 characterized Gag-ESCRT interaction motifs (late domains are not required for VLP budding, 2 loss of function alleles of the essential HECT ubiquitin ligase Rsp5 do not display defects in VLP formation, and 3 ESCRT function is not required for VLP formation from spheroplasts. These results suggest that the egress of HIV Gag from yeast cells is distinct from the most commonly described mode of exit from mammalian cells, instead mimicking ESCRT-independent VLP formation observed in a subset of mammalian cells. As such, budding of Gag from yeast cells appears to represent ESCRT-independent budding relevant to viral replication in at least some situations. Thus the myriad of genetic and biochemical tools available in the yeast system may be of utility in the study of this aspect of viral budding.

  10. Temperature dependence of single-particle properties in nuclear matter

    International Nuclear Information System (INIS)

    Zuo, W.; Lu, G.C.; Li, Z.H.; Lombardo, U.; Schulze, H.-J.

    2006-01-01

    The single-nucleon potential in hot nuclear matter is investigated in the framework of the Brueckner theory by adopting the realistic Argonne V 18 or Nijmegen 93 two-body nucleon-nucleon interaction supplemented by a microscopic three-body force. The rearrangement contribution to the single-particle potential induced by the ground state correlations is calculated in terms of the hole-line expansion of the mass operator and provides a significant repulsive contribution in the low-momentum region around and below the Fermi surface. Increasing temperature leads to a reduction of the effect, while increasing density makes it become stronger. The three-body force suppresses somewhat the ground state correlations due to its strong short-range repulsion, increasing with density. Inclusion of the three-body force contribution results in a quite different temperature dependence of the single-particle potential at high enough densities as compared to that adopting the pure two-body force. The effects of three-body force and ground state correlations on the nucleon effective mass are also discussed

  11. Fluctuations of the single-particle density in nuclear dynamics

    International Nuclear Information System (INIS)

    Burgio, G.F.; Chomaz, P.; Randrup, J.

    1991-01-01

    In recent years semiclassical methods have been developed to study heavy-ion collisions in the framework of the Boltzmann-Uehling-Uhlenbeck theory, in which the collisionless mean field evolution has been augmented by a Pauli-blocked Nordheim collision term. Since these models describe the average dynamic trajectory, they cannot be applied to describe fluctuations of one-body observables, correlations in the emission of light particles and catastrophic processes like multifragmentation. The authors have developed a new method in order to include the stochastic part of the collision integral into BUU-type simulations of the nuclear dynamics. They apply this method to a two-dimensional gas of fermions on a torus, for which the time evolution of the mean trajectory and the associated correlation function are calculated; the variance of the phase-space occupancy follows closely the predictions of the corresponding Fokker-Planck equation and relaxes towards the appropriate quantum-statistical limit. The breaking of the translational and spherical symmetry in the model permits the study of unstable situations in phase-space. The introduction of the nonlinear one-body field allows them to explore dynamical instabilities and bifurcations. Therefore the model can be appropriate for studying nuclear multifragmentation

  12. Particle physics contribution to the elimination of nuclear waste

    International Nuclear Information System (INIS)

    Revol, Jean-Pierre

    2001-01-01

    My introduction on fundamental research and innovation will explain how CERN, a laboratory which is a priori entirely dedicated to fundamental research, came to contribute to a major challenge of society: the energy problem. I will describe the motivation behind the original experimental effort carried out at CERN (FEAT and TARC experiments) and discuss some of the main elements of the energy problem. Progress in particle accelerator technology makes it possible nowadays to use a proton accelerator to produce energy and eliminate nuclear waste efficiently. The Energy Amplifier proposed by Carlo Rubbia and his group is a subcritical fast neutron system driven by a proton accelerator. It is particularly attractive as it could destroy, through fission, transuranic elements produced by present nuclear reactors. The Energy Amplifier could also efficiently transform long lived fission fragments at minimal cost using the concept of Adiabatic Resonance Crossing (ARC) recently tested at CERN with the TARC experiment. The ARC concept can be extended to several other domains of application (production of radioactive isotopes for medicine and industry, neutron research applications, etc.)

  13. Data-driven model-independent searches for long-lived particles at the LHC

    Science.gov (United States)

    Coccaro, Andrea; Curtin, David; Lubatti, H. J.; Russell, Heather; Shelton, Jessie

    2016-12-01

    Neutral long-lived particles (LLPs) are highly motivated by many beyond the Standard Model scenarios, such as theories of supersymmetry, baryogenesis, and neutral naturalness, and present both tremendous discovery opportunities and experimental challenges for the LHC. A major bottleneck for current LLP searches is the prediction of Standard Model backgrounds, which are often impossible to simulate accurately. In this paper, we propose a general strategy for obtaining differential, data-driven background estimates in LLP searches, thereby notably extending the range of LLP masses and lifetimes that can be discovered at the LHC. We focus on LLPs decaying in the ATLAS muon system, where triggers providing both signal and control samples are available at LHC run 2. While many existing searches require two displaced decays, a detailed knowledge of backgrounds will allow for very inclusive searches that require just one detected LLP decay. As we demonstrate for the h →X X signal model of LLP pair production in exotic Higgs decays, this results in dramatic sensitivity improvements for proper lifetimes ≳10 m . In theories of neutral naturalness, this extends reach to glueball masses far below the b ¯b threshold. Our strategy readily generalizes to other signal models and other detector subsystems. This framework therefore lends itself to the development of a systematic, model-independent LLP search program, in analogy to the highly successful simplified-model framework of prompt searches.

  14. SPOUTED BED DESIGN CONSIDERATIONS FOR COATED NUCLEAR FUEL PARTICLES

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, Douglas W.

    2017-07-01

    High Temperature Gas Cooled Reactors (HTGRs) are fueled with tristructural isotropic (TRISO) coated nuclear fuel particles embedded in a carbon-graphite fuel body. TRISO coatings consist of four layers of pyrolytic carbon and silicon carbide that are deposited on uranium ceramic fuel kernels (350µm – 500µm diameters) in a concatenated series of batch depositions. Each layer has dedicated functions such that the finished fuel particle has its own integral containment to minimize and control the release of fission products into the fuel body and reactor core. The TRISO coatings are the primary containment structure in the HTGR reactor and must have very high uniformity and integrity. To ensure high quality TRISO coatings, the four layers are deposited by chemical vapor deposition (CVD) using high purity precursors and are applied in a concatenated succession of batch operations before the finished product is unloaded from the coating furnace. These depositions take place at temperatures ranging from 1230°C to 1550°C and use three different gas compositions, while the fuel particle diameters double, their density drops from 11.1 g/cm3 to 3.0 g/cm3, and the bed volume increases more than 8-fold. All this is accomplished without the aid of sight ports or internal instrumentation that could cause chemical contamination within the layers or mechanical damage to thin layers in the early stages of each layer deposition. The converging section of the furnace retort was specifically designed to prevent bed stagnation that would lead to unacceptably high defect fractions and facilitate bed circulation to avoid large variability in coating layer dimensions and properties. The gas injection nozzle was designed to protect precursor gases from becoming overheated prior to injection, to induce bed spouting and preclude bed stagnation in the bottom of the retort. Furthermore, the retort and injection nozzle designs minimize buildup of pyrocarbon and silicon carbide on the

  15. Fractionation of HeLa cell nuclear extracts reveals minor small nuclear ribonucleoprotein particles

    International Nuclear Information System (INIS)

    Kroemer, A.

    1987-01-01

    Upon chromatographic fractionation of HeLa cell nuclear extracts, small RNAs of 145 and 66/65 nucleotides, respectively, were detected that are distinct from the abundant small RNAs present in the extract. These RNAs are precipitated by antibodies directed against the trimethylguanosine cap structure, characteristic for small nuclear RNAs (snRNAs) of the U type. The RNAs of 145 and 66/65 nucleotides appear to be associated with at least one of the proteins common to the major small nuclear ribonucleoprotein particles U1 to U6, since they are specifically bound by anti-Sm antibodies. These criteria characterize the RNAs that are 145 and 66/65 nucleotides in length as U-type snRNAs. Upon gel filtration, the RNAs are found within particles of molecular weights ≅ 150,000 and 115,000 respectively. The RNA of 145 nucleotides represents a different minor snRNA, designated U11, whereas the RNA of 66/65 nucleotides may correspond to either mammalian U7 or U10 RNA

  16. Proposal of guidelines for structuring an independent regulation body for the Brazilian nuclear sector

    International Nuclear Information System (INIS)

    Nicoll Junior, Ricardo

    2016-01-01

    Regulatory bodies are responsible for regulation in various sectors of society. In Brazil, they work in various areas for the development of the country and have as main objective the social, economic and national development. The progress of new technologies in the nuclear field and their commercialization underscores the need for regulation according to international safety standards. The present research searches through an extensive review of the literature identify the international guidelines for regulatory bodies and make a comparative analysis between Brazil and five countries that have independent regulatory bodies in the nuclear sector. The purpose of the work is to contribute to the Brazilian public sectors, with an evaluation of the country's regulation in the perception of specialists and propose guidelines for the structuring of an independent regulatory body, respecting international agreements and the legislation in force in the country. (author)

  17. Nuclear emulsion experiments on particle production at high energies

    International Nuclear Information System (INIS)

    Otterlund, I.

    1976-08-01

    Various experimental results, including multiplicities of shower-particles and heavy prong particles, correlations between them and single particle distributions, from proton-emulsion nucleus reactions in the energy range 200-400 GeV are presented. (Auth.)

  18. Effect of Particle Size Distribution on Slurry Rheology: Nuclear Waste Simulant Slurries

    International Nuclear Information System (INIS)

    Chun, Jaehun; Oh, Takkeun; Luna, Maria L.; Schweiger, Michael J.

    2011-01-01

    Controlling the rheological properties of slurries has been of great interest in various industries such as cosmetics, ceramic processing, and nuclear waste treatment. Many physicochemical parameters, such as particle size, pH, ionic strength, and mass/volume fraction of particles, can influence the rheological properties of slurry. Among such parameters, the particle size distribution of slurry would be especially important for nuclear waste treatment because most nuclear waste slurries show a broad particle size distribution. We studied the rheological properties of several different low activity waste nuclear simulant slurries having different particle size distributions under high salt and high pH conditions. Using rheological and particle size analysis, it was found that the percentage of colloid-sized particles in slurry appears to be a key factor for rheological characteristics and the efficiency of rheological modifiers. This behavior was shown to be coupled with an existing electrostatic interaction between particles under a low salt concentration. Our study suggests that one may need to implement the particle size distribution as a critical factor to understand and control rheological properties in nuclear waste treatment plants, such as the U.S. Department of Energy's Hanford and Savannah River sites, because the particle size distributions significantly vary over different types of nuclear waste slurries.

  19. 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)

  20. Welding and nondestructive examination issues at Seabrook Nuclear Station: An independent review team report

    International Nuclear Information System (INIS)

    Spessard, R.L.; Coley, J.; Crowley, W.; Walton, G.

    1990-07-01

    In response to congressional concerns about the adequacy of the welding and nondestructive examination (NDE) programs at the Seabrook Nuclear Station, NRC senior management established an independent review team (IRT) to conduct an assessment. The IRT focused on the quality of the finished hardware and associated records, as well as on the adequacy of the overall quality assurance program as applied to the fabrication and NDE programs for pipe welds. This report documents the findings of that investigation

  1. Nuclear material accounting and control: Co-ordinating assistance to newly independent States

    International Nuclear Information System (INIS)

    Thorstensen, S.

    1995-01-01

    This article outlines work under way among the IAEA, its Member States, and the Newly Independent States (NIS) relating to the establishment and development in the NIS of State Systems of Accounting and Control (SSACs) of nuclear material. It describes IAEA activities in the NIS, including fact-finding missions at technical visits, the successful attempts to find donor States providing voluntary funding and expertise, and the co-ordination of technical support between the IAEA and the donor States. 3 tabs

  2. Particle identification by nuclear emulsions in the OPERA experiment

    International Nuclear Information System (INIS)

    Manai, Kais

    2007-01-01

    The OPERA experiment will try to confirm the ν μ →ν τ oscillations by the appearance of the ν τ in a pure ν μ beam. Indeed, a neutrino beam almost pure is produced at CERN (CNGS Beam) and sent to the OPERA detector. The detector is composed of two muons spectrometers and a target formed by walls of bricks. Each brick is an alternation of lead plates and emulsions. This modular structure allows to reconstruct the kink topology of the τ lepton decay with a high spatial resolution. The great challenge of the OPERA experiment is to detect the ν τ interactions with the less uncertainty. To reduce this uncertainty it is essential to identify with the greatest efficiency any background event not including a tau particle. My work permits to reduce background. My principal contribution concerns the selection development, the reconstruction and the muons identification at low energy. This work is based on the setting of variables related to the deposit energy and the multiple scattering. Previously, only deposit energy was used in the analyses of pion/muon separation. This study allows doubling the muon identification efficiency at low energy. This leads to increase the background events rejection in OPERA and to decrease the contamination by 30 pour cent. I also studied the nuclear emulsions capacity to identify charged particles through the analysis of a test beam carried out by the Nagoya group. This test contains protons and pions with different energies. My work proves that the European scan system gives comparable results with those obtained by the Japanese scan system. (Author)

  3. 78 FR 40200 - Duke Energy Carolinas, LLC, Oconee Nuclear Station Units 1, 2, and 3; Independent Spent Fuel...

    Science.gov (United States)

    2013-07-03

    ... NUCLEAR REGULATORY COMMISSION [Docket Nos. 72-1004, 72-40, 50-269, 50-270, and 50-287; NRC-2013-0135] Duke Energy Carolinas, LLC, Oconee Nuclear Station Units 1, 2, and 3; Independent Spent Fuel Storage Installation; Environmental Assessment and Finding of No Significant Impact AGENCY: Nuclear...

  4. 78 FR 45575 - Duke Energy Carolinas, LLC; Oconee Nuclear Station Units 1, 2, and 3; Independent Spent Fuel...

    Science.gov (United States)

    2013-07-29

    ... NUCLEAR REGULATORY COMMISSION [Docket Nos.: 72-1004, 72-40, 50-269, 50-270, 50-287; and NRC-2013- 0135] Duke Energy Carolinas, LLC; Oconee Nuclear Station Units 1, 2, and 3; Independent Spent Fuel Storage Installation AGENCY: Nuclear Regulatory Commission. ACTION: Exemption; issuance. SUMMARY: The NRC...

  5. Softness of Nuclear Matter and the Production of Strange Particles in Neutron Stars

    Institute of Scientific and Technical Information of China (English)

    陈伟; 文德华; 刘良钢

    2003-01-01

    In the various models, we study the influences of the softness of nuclear matter, the vacuum fluctuation ofnucleons and σ mesons on the production of strange particles in neutron stars. Wefind that the stiffer the nuclear matter is, the more easily the strange particles is produced in neutron stars. The vacuum fluctuation of nucleons has large effect on strange particle production while that of σ meson has little effect on it.

  6. Digital signal processing algorithms for nuclear particle spectroscopy

    International Nuclear Information System (INIS)

    Zejnalova, O.; Zejnalov, Sh.; Hambsch, F.J.; Oberstedt, S.

    2007-01-01

    Digital signal processing algorithms for nuclear particle spectroscopy are described along with a digital pile-up elimination method applicable to equidistantly sampled detector signals pre-processed by a charge-sensitive preamplifier. The signal processing algorithms are provided as recursive one- or multi-step procedures which can be easily programmed using modern computer programming languages. The influence of the number of bits of the sampling analogue-to-digital converter on the final signal-to-noise ratio of the spectrometer is considered. Algorithms for a digital shaping-filter amplifier, for a digital pile-up elimination scheme and for ballistic deficit correction were investigated using a high purity germanium detector. The pile-up elimination method was originally developed for fission fragment spectroscopy using a Frisch-grid back-to-back double ionization chamber and was mainly intended for pile-up elimination in case of high alpha-radioactivity of the fissile target. The developed pile-up elimination method affects only the electronic noise generated by the preamplifier. Therefore the influence of the pile-up elimination scheme on the final resolution of the spectrometer is investigated in terms of the distance between pile-up pulses. The efficiency of the developed algorithms is compared with other signal processing schemes published in literature

  7. Parallel particle swarm optimization algorithm in nuclear problems

    International Nuclear Information System (INIS)

    Waintraub, Marcel; Pereira, Claudio M.N.A.; Schirru, Roberto

    2009-01-01

    Particle Swarm Optimization (PSO) is a population-based metaheuristic (PBM), in which solution candidates evolve through simulation of a simplified social adaptation model. Putting together robustness, efficiency and simplicity, PSO has gained great popularity. Many successful applications of PSO are reported, in which PSO demonstrated to have advantages over other well-established PBM. However, computational costs are still a great constraint for PSO, as well as for all other PBMs, especially in optimization problems with time consuming objective functions. To overcome such difficulty, parallel computation has been used. The default advantage of parallel PSO (PPSO) is the reduction of computational time. Master-slave approaches, exploring this characteristic are the most investigated. However, much more should be expected. It is known that PSO may be improved by more elaborated neighborhood topologies. Hence, in this work, we develop several different PPSO algorithms exploring the advantages of enhanced neighborhood topologies implemented by communication strategies in multiprocessor architectures. The proposed PPSOs have been applied to two complex and time consuming nuclear engineering problems: reactor core design and fuel reload optimization. After exhaustive experiments, it has been concluded that: PPSO still improves solutions after many thousands of iterations, making prohibitive the efficient use of serial (non-parallel) PSO in such kind of realworld problems; and PPSO with more elaborated communication strategies demonstrated to be more efficient and robust than the master-slave model. Advantages and peculiarities of each model are carefully discussed in this work. (author)

  8. Nuclear fragmentation and the number of particle tracks in tissue

    International Nuclear Information System (INIS)

    Ponomarev, A. L.; Cucinotta, F. A.

    2006-01-01

    For high energy nuclei, the number of particle tracks per cell is modified by local nuclear reactions that occur, with large fluctuations expected for heavy ion tracks. Cells near the interaction site of a reaction will experience a much higher number of tracks than estimated by the average fluence. Two types of reaction products are possible and occur in coincidence; projectile fragments, which generally have smaller charge and similar velocity to that of the projectile, and target fragments, which are produced from the fragmentation of the nuclei of water atoms or other cellular constituents with low velocity. In order to understand the role of fragmentation in biological damage a new model of human tissue irradiated by heavy ions was developed. A box of the tissue is modelled with periodic boundary conditions imposed, which extrapolates the technique to macroscopic volumes of tissue. The cross sections for projectile and target fragmentation products are taken from the quantum multiple scattering fragmentation code previously developed at NASA Johnson Space Center. Statistics of fragmentation pathways occurring in a cell monolayer, as well as in a small volume of 10 x 10 x 10 cells are given. A discussion on approaches to extend the model to describe spatial distributions of inactivated or other cell damage types, as well as highly organised tissues of multiple cell types, is presented. (authors)

  9. IAEA Assistance in Helping Member States Develop Effectively Independent and Robust Regulators for Nuclear Installation Safety

    Energy Technology Data Exchange (ETDEWEB)

    Nicic, A., E-mail: A.Nicic@iaea.org [International Atomic Energy Agency (IAEA), Department of Nuclear Safety and Security, Wagramer Strasse 5, P.O. Box 100, 1400 Vienna (Austria)

    2014-10-15

    Full text: The International Conference on Topical Issues in Nuclear Installation Safety will be focused on the exchange of information on the latest thinking and advances in the implementation of the concept of Defence-in-Depth (DID) in nuclear installations, and the associated challenges. The focus will be on operating nuclear installations, including nuclear power plants, research reactors and fuel cycle facilities, and on how lessons learned from operating experience and recent events (e.g. the Fukushima Daiichi accident) are used to enhance safety. The implementation of DID covers a number of elements that are directly related to the different states and phases of a nuclear facility. This presentation will discuss the importance of the regulatory body in its oversight role as a cross-cutting element of DID in helping to assure the safety of nuclear installations. Taking note of the numerous challenges in developing an effectively independent and robust regulatory body, the presentation will describe how the IAEA assists Member States in their development of the appropriate regulatory infrastructure and necessary capacity to carry out their regulatory responsibilities – consistent with the IAEA Safety Standards. The presentation will describe the importance of the self-assessment process which serves as a starting point for helping Member States gain an understanding of what support they need and when the support should be provided as they develop into a competent regulatory authority. The presentation will discuss recent improvements in the self-assessment process and related IAEA services in this regard. Once regulatory bodies are established, it is essential that they seek continuous improvement. In this regard, the presentation will describe the IAEA’s assistance provided through the Integrated Regulatory Review Service (IRRS) and recent activities to improve the IRRS, consistent with the IAEA’s Action Plan on Nuclear Safety. (author)

  10. Multiparticle Production in Particle and Nuclear Collisions. I

    Science.gov (United States)

    Kanki, T.; Kinoshita, K.; Sumiyoshi, H.; Takagi, F.

    The dominant phenomenon in high-energy particle and nuclear collisions is multiple production of hadrons. This had attracted may physicists in 1950's, the period of the first remarkable development of particle physics. Multiparticle production was already observed in cosmic-ray experiments and expected to be explained as a natural consequence of the strong Yukawa interaction. Statistical and hydrodynamical models were then proposed by Fermi, Landau and others. These theories are still surviving even today as a prototype of modern ``fire-ball'' models. After twenty years, a golden age came in this field of physics. It was closely related to the rapid development of accelerator facilities, especially, the invention of colliding-beam machines which yield high enough center-of-mass energies for studying reactions with high multiplicity. Abundant data on final states of multiparticle production have been accumulated mainly by measuring inclusive cross sections and multiplicity distributions. In super high-energy bar{p}p collisions at CERN S pmacr pS Collider, we confirmed the increasing total cross section and found violations of many scaling laws which seemed to be valid at lower energies. This suggests a fundamental complexity of the multiparticle phenomena and offers new materials for further development of theoretical investigations. In the same period, studies of constituent (quark-gluon) structure of hadrons had also been develped. Nowadays, pysicists believe that the quantum chromodynamics (QCD) is the fundamental law of the hadronic world. Multiparticle dynamics should also be described by QCD. We have known that the hard-jet phenomena are well explained by the perturbative QCD. On the other hand, the soft processes are considered to be non-perturbative phenomena which have not yet been solved, and related to the mechanism of the color confinement and formation of strings or color-flux tubes. Multiparticle production would offer useful information on this

  11. Multiparticle Production in Particle and Nuclear Collisions. II

    Science.gov (United States)

    Kanki, T.; Kinoshita, K.; Sumiyoshi, H.; Takagi, F.

    The dominant phenomenon in high-energy particle and nuclear collisions is multiple production of hadrons. This had attracted may physicists in 1950's, the period of the first remarkable development of particle physics. Multiparticle production was already observed in cosmic-ray experiments and expected to be explained as a natural consequence of the strong Yukawa interaction. Statistical and hydrodynamical models were then proposed by Fermi, Landau and others. These theories are still surviving even today as a prototype of modern ``fire-ball'' models. After twenty years, a golden age came in this field of physics. It was closely related to the rapid development of accelerator facilities, especially, the invention of colliding-beam machines which yield high enough center-of-mass energies for studying reactions with high multiplicity. Abundant data on final states of multiparticle production have been accumulated mainly by measuring inclusive cross sections and multiplicity distributions. In super high-energy bar{p}p collisions at CERN S pmacr pS Collider, we confirmed the increasing total cross section and found violations of many scaling laws which seemed to be valid at lower energies. This suggests a fundamental complexity of the multiparticle phenomena and offers new materials for further development of theoretical investigations. In the same period, studies of constituent (quark-gluon) structure of hadrons had also been develped. Nowadays, pysicists believe that the quantum chromodynamics (QCD) is the fundamental law of the hadronic world. Multiparticle dynamics should also be described by QCD. We have known that the hard-jet phenomena are well explained by the perturbative QCD. On the other hand, the soft processes are considered to be non-perturbative phenomena which have not yet been solved, and related to the mechanism of the color confinement and formation of strings or color-flux tubes. Multiparticle production would offer useful information on this

  12. Development of vendor independent safety analysis capability for nuclear power plants in Taiwan

    International Nuclear Information System (INIS)

    Tang, J.-R.

    2001-01-01

    The Institute of Nuclear Energy Research (INER) and the Taiwan Power Company (TPC) have long-term cooperation to develop vendor independent safety analysis capability to provide support to nuclear power plants in Taiwan in many aspects. This paper presents some applications of this analysis capability, introduces the analysis methodology, and discusses the significance of vendor independent analysis capability now and future. The applications include a safety analysis of core shroud crack for Chinshan BWR/4 Unit 2, a parallel reload safety analysis of the first 18-month extended fuel cycle for Kuosheng BWR/6 Unit 2 Cycle 13, an analysis to support Technical Specification change for Maanshan three-loop PWR, and a design analysis to support the review of Preliminary Safety Analysis Report of Lungmen ABWR. In addition, some recent applications such as an analysis to support the review of BWR fuel bid for Chinshan and Kuosheng demonstrates the needs of further development of the analysis capability to support nuclear power plants in the 21 st century. (authors)

  13. The official report of the Fukushima Nuclear Accident Independent Investigation Commission

    International Nuclear Information System (INIS)

    2012-07-01

    In October 2011, the Act regarding Fukushima Nuclear Accident Independent Investigation Commission was enacted to investigate the Fukushima accident with the authority to request documents and request the legislative branch to use its investigative powers to obtain any necessary documents or evidence required. In December 2011, chairman and nine other members were appointed. After a six-month investigation, Commission had concluded. 'In order to prevent future disasters, fundamental reforms must take place covering both the structure of electric power industry and the structure of related government and regulatory agencies as well as operation processes, for both normal and emergency situations'. Main parts of report consisted of overview, conclusions and recommendations, and six findings; (1) was the accident preventable?, (2) Escalation of the accident, (3) Emergency response to the accident, (4) Spread of the damage, (5) Organizational issues in accident prevention and response and (6) the legal system. Based on the above findings, Commission made seven recommendations regarding (1) Monitoring of the nuclear regulatory body by the National Diet, (2) Reform the crisis management system, (3) Government responsibility for public health and welfare, (4) Monitoring the operators, (5) Criteria for the new regulatory body, (6) Reforming laws related to nuclear energy and (7) Develop a system of independent investigation commissions. National Diet's thorough debate and deliberate on these recommendation was highly encouraged for the future. (T. Tanaka)

  14. The Independence of the Nuclear Regulator: Notes from the Canadian Experience

    International Nuclear Information System (INIS)

    MacKenzie, B.

    2010-01-01

    The firing of Linda Keen as president and chief executive Officer of the Canadian Nuclear Safety Commission provoked considerable debate within Canada and internationally about the independence of the canadian nuclear regulator. ms. Keen was dismissed from her position from her position at the height of the crisis over a world-wide shortage of medical isotopes caused by the shutdown of the research reactor in Chalk river, Ontario. Under the terms of its licence, the reactor was required to have cooling pumps connected to an emergency power supply as a backup in case of a power outage caused by an event such an earthquake. In november 2007, after it was discovered that the pumps were not connected, the reactor was shut down. As panic over the shortage of medical isotopes grew, the government took three extraordinary measures: first, it issued a directive; second, it introduced emergency legislation in Parliament; and finally, it fired Linda Keen as President of the Commission. This paper examines those three measures and whether they constituted an unwarranted interference with the independence of the Canadian nuclear regulator. (N.C.)

  15. Primary studies on particle recovery of swipe samples for nuclear safeguards

    International Nuclear Information System (INIS)

    Fan Wang; Yan Chen; Yong-gang Zhao; Yan Zhang; Tong-xing Wang; Jing-huai Li; Zhi-yuan Chang; Hai-ping Cui

    2013-01-01

    Environmental sampling plays a significant role in nuclear safeguards. Isotopic ratio in uranium-bearing particles from swipe samples provides important information for detecting undeclared activities. Particle recovery which is the primary step of particle analysis, would affect the following analysis. The particle recovery efficiency of ultrasoneration recovery and vacuum suction-impact recovery were measured by alpha spectrometer with standard particles produced via aerosol spray pyrolysis method. The conditions of ultrasoneration were optimized and both recovery methods were evaluated. Finally, a procedure of particle recovery for unknown swipe samples was set up. (author)

  16. Measurement of fission track of uranium particle by solid state nuclear track detector

    International Nuclear Information System (INIS)

    Son, S. C.; Pyo, H. W.; Ji, K. Y.; Kim, W. H.

    2002-01-01

    In this study, we discussed results of the measurement of fission tracks for the uranium containing particles by solid state nuclear track detector. Uranium containing silica and uranium oxide particles were prepared by uranium sorption onto silica powder in weak acidic medium and laser ablation on uranium pellet, respectively. Fission tracks for the uranium containing silica and uranium oxide particles were detected on Lexan plastic detector. It was found that the fission track size and shapes depend on the particle size uranium content in particles. Correlation of uranium particle diameter with fission track radius was also discussed

  17. Independent Commission for Radiological Protection and Nuclear Safety CIPRSN: Balance, obligations and future prospects

    International Nuclear Information System (INIS)

    Gieb, M.; Meruje, M. M; Sena Lino, A.

    2010-01-01

    This article summarizes the historical context of the regulatory situation in Portugal that led to the creation of the technical team of the Independent Commission for Radiological Protection and Nuclear Safety (CIPRSN), recalls its early works, and highlights the current work of some members of the team on the self-assessment of the national regulatory system of radiological protection and nuclear safety. The result of this self-assessment allows a detailed analysis of current problems and makes it possible to outline the future work plan of the technical team. It is hoped that this work may contribute to an improvement of the system, especially in view of new international and European legal instruments which are currently under implementation. (author)

  18. Independent tube verification and dynamic tracking in et inspection of nuclear steam generator

    International Nuclear Information System (INIS)

    Xiongzi, Li; Zhongxue, Gan; Lance, Fitzgibbons

    2001-01-01

    The full text follows. In the examination of pressure boundary tubes in steam generators of commercial pressurized water nuclear power plants (PWR's), it is critical to know exactly which particular tube is being accessed. There are no definitive landmarks or markings on the individual tubes. Today this is done manually, it is tedious, and interrupts the normal inspection work, and is difficult due to the presence of water on the tube surface, plug ends instead of tube openings in the field of view, and varying lighting quality. In order to eliminate the human error and increase the efficiency of operation, there is a need to identify tube position during the inspection process, independent of robot encoder position and motion. A process based on a Cognex MVS-8200 system and its application function package has been developed to independently identify tube locations. ABB Combustion Engineering Nuclear Power's Outage Services group, USPPL in collaboration with ABB Power Plant Laboratories' Advanced Computers and Controls department has developed a new vision-based Independent Tube Verification system (GENESIS-ITVS-TM ). The system employ's a model-based tube-shape detection algorithm and dynamic tracking methodology to detect the true tool position and its offsets from identified tube location. GENESIS-ITVS-TM is an automatic Independent Tube Verification System (ITVS). Independent tube verification is a tube validation technique using computer vision, and not using any robot position parameters. This process independently counts the tubes in the horizontal and vertical axes of the plane of the steam generator tube sheet as the work tool is moved. Thus it knows the true position in the steam generator, given a known starting point. This is analogous to the operator's method of counting tubes for verification, but it is automated. GENESIS-ITVS-TM works independent of the robot position, velocity, or acceleration. The tube position information is solely obtained from

  19. [Studies of nuclear structure using neutrons and charged particles

    International Nuclear Information System (INIS)

    1989-01-01

    This report contains brief discussions on nuclear research done at Triangle Universities Nuclear Laboratory. The major categories covered are: Fundamental symmetries in the nucleus; Dynamics in very light nuclei; D states in light nuclei; Nucleon-nucleus interactions; Nuclear structure and reactions; and Instrumentation and development

  20. Retrieval of spheroid particle size distribution from spectral extinction data in the independent mode using PCA approach

    International Nuclear Information System (INIS)

    Tang, Hong; Lin, Jian-Zhong

    2013-01-01

    An improved anomalous diffraction approximation (ADA) method is presented for calculating the extinction efficiency of spheroids firstly. In this approach, the extinction efficiency of spheroid particles can be calculated with good accuracy and high efficiency in a wider size range by combining the Latimer method and the ADA theory, and this method can present a more general expression for calculating the extinction efficiency of spheroid particles with various complex refractive indices and aspect ratios. Meanwhile, the visible spectral extinction with varied spheroid particle size distributions and complex refractive indices is surveyed. Furthermore, a selection principle about the spectral extinction data is developed based on PCA (principle component analysis) of first derivative spectral extinction. By calculating the contribution rate of first derivative spectral extinction, the spectral extinction with more significant features can be selected as the input data, and those with less features is removed from the inversion data. In addition, we propose an improved Tikhonov iteration method to retrieve the spheroid particle size distributions in the independent mode. Simulation experiments indicate that the spheroid particle size distributions obtained with the proposed method coincide fairly well with the given distributions, and this inversion method provides a simple, reliable and efficient method to retrieve the spheroid particle size distributions from the spectral extinction data. -- Highlights: ► Improved ADA is presented for calculating the extinction efficiency of spheroids. ► Selection principle about spectral extinction data is developed based on PCA. ► Improved Tikhonov iteration method is proposed to retrieve the spheroid PSD.

  1. Mean multiplicity of secondary particles in hadron-nuclear interactions

    International Nuclear Information System (INIS)

    Alaverdyan, G.B.; Pak, A.S.

    1980-01-01

    The mean multiplicity of secondary particles in hA interactions is examined in the framework of the multiplex scattering theory. The dependence of the secondary particle multiplicity coefficient Rsub(6)=anti nsub(hA)/anti nsub(hN) (where anti nsub(hA) and anti nsub(hN) are mean multiplicities of secondary relativistic particles in hA and hN interactions, respectively) on the energy and type of incident particles and atomic number of a target nucleus is analysed. It is shown that predictions of the leading particle cascade model are in satisfactory agreement with the experimental data if the uncertainties of the inelasticity in hN interactions are taken into account. The value Rsub(A) weakly depends both on the incident particle energy and the form of parametrization anti nsub(hN)(E). Allowance of energy losses fluctuation of leading particle results in the Rsub(A) value decrease. From the model of leading particles it does not follow that Rsub(a) strictly depends on the type of incident particles at the fixed value of mean number of collisions. But quantitative values of Rsub(A) for different types of particles and at one value of anti ν, (i.e. at properly chosen value) coincide. The value of Rsub(A) is profoundly dependent on the values of inelasticity factor in hN interactions

  2. Quasifree (p , 2 p ) Reactions on Oxygen Isotopes: Observation of Isospin Independence of the Reduced Single-Particle Strength

    Science.gov (United States)

    Atar, L.; Paschalis, S.; Barbieri, C.; Bertulani, C. A.; Díaz Fernández, P.; Holl, M.; Najafi, M. A.; Panin, V.; Alvarez-Pol, H.; Aumann, T.; Avdeichikov, V.; Beceiro-Novo, S.; Bemmerer, D.; Benlliure, J.; Boillos, J. M.; Boretzky, K.; Borge, M. J. G.; Caamaño, M.; Caesar, C.; Casarejos, E.; Catford, W.; Cederkall, J.; Chartier, M.; Chulkov, L.; Cortina-Gil, D.; Cravo, E.; Crespo, R.; Dillmann, I.; Elekes, Z.; Enders, J.; Ershova, O.; Estrade, A.; Farinon, F.; Fraile, L. M.; Freer, M.; Galaviz Redondo, D.; Geissel, H.; Gernhäuser, R.; Golubev, P.; Göbel, K.; Hagdahl, J.; Heftrich, T.; Heil, M.; Heine, M.; Heinz, A.; Henriques, A.; Hufnagel, A.; Ignatov, A.; Johansson, H. T.; Jonson, B.; Kahlbow, J.; Kalantar-Nayestanaki, N.; Kanungo, R.; Kelic-Heil, A.; Knyazev, A.; Kröll, T.; Kurz, N.; Labiche, M.; Langer, C.; Le Bleis, T.; Lemmon, R.; Lindberg, S.; Machado, J.; Marganiec-Gałązka, J.; Movsesyan, A.; Nacher, E.; Nikolskii, E. Y.; Nilsson, T.; Nociforo, C.; Perea, A.; Petri, M.; Pietri, S.; Plag, R.; Reifarth, R.; Ribeiro, G.; Rigollet, C.; Rossi, D. M.; Röder, M.; Savran, D.; Scheit, H.; Simon, H.; Sorlin, O.; Syndikus, I.; Taylor, J. T.; Tengblad, O.; Thies, R.; Togano, Y.; Vandebrouck, M.; Velho, P.; Volkov, V.; Wagner, A.; Wamers, F.; Weick, H.; Wheldon, C.; Wilson, G. L.; Winfield, J. S.; Woods, P.; Yakorev, D.; Zhukov, M.; Zilges, A.; Zuber, K.; R3B Collaboration

    2018-01-01

    Quasifree one-proton knockout reactions have been employed in inverse kinematics for a systematic study of the structure of stable and exotic oxygen isotopes at the R3B /LAND setup with incident beam energies in the range of 300 - 450 MeV /u . The oxygen isotopic chain offers a large variation of separation energies that allows for a quantitative understanding of single-particle strength with changing isospin asymmetry. Quasifree knockout reactions provide a complementary approach to intermediate-energy one-nucleon removal reactions. Inclusive cross sections for quasifree knockout reactions of the type O A (p ,2 p )N-1A have been determined and compared to calculations based on the eikonal reaction theory. The reduction factors for the single-particle strength with respect to the independent-particle model were obtained and compared to state-of-the-art ab initio predictions. The results do not show any significant dependence on proton-neutron asymmetry.

  3. Cross sections of nuclear reactions induced by protons, deuterons, and alpha particles. Pt.6. Phosphorus

    International Nuclear Information System (INIS)

    Tobailem, Jacques.

    1981-11-01

    Cross sections are reviewed for nuclear reactions induced by protons, deuterons, and alpha particles on phosphorus targets. When necessary, published experimental data are corrected, and, when possible, excitation functions are proposed [fr

  4. Continuous spectrum of electromagnetic radiation in the collision of nuclear particles

    International Nuclear Information System (INIS)

    Amusia, M.Y.; Solovyov, A.V.

    1988-01-01

    The bremsstrahlung arising at the scattering of various particles on a nucleus has been considered with the demonstration of an important participation of the nuclear polarization in the collision process

  5. Characterization of nuclear physics targets using Rutherford backscattering and particle induced X-ray emission

    International Nuclear Information System (INIS)

    Rubehn, T.; Wozniak, G.J.; Phair, L.; Moretto, L.G.; Yu, K.M.

    1997-01-01

    Rutherford backscattering and particle induced X-ray emission have been utilized to precisely characterize targets used in nuclear fission experiments. The method allows for a fast and non-destructive determination of target thickness, homogeneity and element composition. (orig.)

  6. Nuclear fuel particles in the environment - characteristics, atmospheric transport and skin doses

    International Nuclear Information System (INIS)

    Poellaenen, R.

    2002-05-01

    In the present thesis, nuclear fuel particles are studied from the perspective of their characteristics, atmospheric transport and possible skin doses. These particles, often referred to as 'hot' particles, can be released into the environment, as has happened in past years, through human activities, incidents and accidents, such as the Chernobyl nuclear power plant accident in 1986. Nuclear fuel particles with a diameter of tens of micrometers, referred to here as large particles, may be hundreds of kilobecquerels in activity and even an individual particle may present a quantifiable health hazard. The detection of individual nuclear fuel particles in the environment, their isolation for subsequent analysis and their characterisation are complicated and require well-designed sampling and tailored analytical methods. In the present study, the need to develop particle analysis methods is highlighted. It is shown that complementary analytical techniques are necessary for proper characterisation of the particles. Methods routinely used for homogeneous samples may produce erroneous results if they are carelessly applied to radioactive particles. Large nuclear fuel particles are transported differently in the atmosphere compared with small particles or gaseous species. Thus, the trajectories of gaseous species are not necessarily appropriate for calculating the areas that may receive large particle fallout. A simplified model and a more advanced model based on the data on real weather conditions were applied in the case of the Chernobyl accident to calculate the transport of the particles of different sizes. The models were appropriate in characterising general transport properties but were not able to properly predict the transport of the particles with an aerodynamic diameter of tens of micrometers, detected at distances of hundreds of kilometres from the source, using only the current knowledge of the source term. Either the effective release height has been higher

  7. Nuclear fuel particles in the environment - characteristics, atmospheric transport and skin doses

    Energy Technology Data Exchange (ETDEWEB)

    Poellaenen, R

    2002-05-01

    In the present thesis, nuclear fuel particles are studied from the perspective of their characteristics, atmospheric transport and possible skin doses. These particles, often referred to as 'hot' particles, can be released into the environment, as has happened in past years, through human activities, incidents and accidents, such as the Chernobyl nuclear power plant accident in 1986. Nuclear fuel particles with a diameter of tens of micrometers, referred to here as large particles, may be hundreds of kilobecquerels in activity and even an individual particle may present a quantifiable health hazard. The detection of individual nuclear fuel particles in the environment, their isolation for subsequent analysis and their characterisation are complicated and require well-designed sampling and tailored analytical methods. In the present study, the need to develop particle analysis methods is highlighted. It is shown that complementary analytical techniques are necessary for proper characterisation of the particles. Methods routinely used for homogeneous samples may produce erroneous results if they are carelessly applied to radioactive particles. Large nuclear fuel particles are transported differently in the atmosphere compared with small particles or gaseous species. Thus, the trajectories of gaseous species are not necessarily appropriate for calculating the areas that may receive large particle fallout. A simplified model and a more advanced model based on the data on real weather conditions were applied in the case of the Chernobyl accident to calculate the transport of the particles of different sizes. The models were appropriate in characterising general transport properties but were not able to properly predict the transport of the particles with an aerodynamic diameter of tens of micrometers, detected at distances of hundreds of kilometres from the source, using only the current knowledge of the source term. Either the effective release height has

  8. Development of a utility system for charged particle nuclear reaction data by using intelligentPad

    International Nuclear Information System (INIS)

    Aoyama, Shigeyoshi; Ohbayashi, Yoshihide; Masui, Hiroshi; Kato, Kiyoshi; Chiba, Masaki

    2000-01-01

    We have developed a utility system, WinNRDF2, for a nuclear charged particle reaction data of NRDF (Nuclear Reaction Data File) on the IntelligentPad architecture. By using the system, we can search the experimental data of a charged particle reaction of NRDF. Furthermore, we also see the experimental data by using graphic pads which was made through the CONTIP project. (author)

  9. Independent Safety Assessment of the TOPAZ-II space nuclear reactor power system (Revised)

    International Nuclear Information System (INIS)

    1993-09-01

    The Independent Safety Assessment described in this study report was performed to assess the safety of the design and launch plans anticipated by the U.S. Department of Defense (DOD) in 1993 for a Russian-built, U.S.-modified, TOPAZ-II space nuclear reactor power system. Its conclusions, and the bases for them, were intended to provide guidance for the U.S. Department of Energy (DOE) management in the event that the DOD requested authorization under section 91b. of the Atomic Energy Act of 1954, as amended, for possession and use (including ground testing and launch) of a nuclear-fueled, modified TOPAZ-II. The scientists and engineers who were engaged to perform this assessment are nationally-known nuclear safety experts in various disciplines. They met with participants in the TOPAZ-II program during the spring and summer of 1993 and produced a report based on their analysis of the proposed TOPAZ-II mission. Their conclusions were confined to the potential impact on public safety and did not include budgetary, reliability, or risk-benefit analyses

  10. Reports and operational engineering: An independent safety assessment of Department of Energy nuclear reactor facilities

    International Nuclear Information System (INIS)

    Rochman, A.; Washburn, B.W.

    1981-02-01

    The Nuclear Facilities Personnel Qualification and Training (NFPQT) Committee, established via an October 24, 1979 memorandum from the Department of Energy (DOE) Under Secretary, was instructed to review the ''Kemeny Commission'' recommendations and to identify possible implications for DOE's nuclear facilities. As a result of this review, the Committee recommended that DOE carry out assessments in seven categories. The assessments would address specific topics identified for each category as delineated in the NFPQT ''Guidelines for Assessing the Safe Operation of DOE-Owned Reactors,'' dated May 7, 1980. The Committee recognized that similar assessments had been ongoing in the DOE program and safety overview organizations since the Three Mile Island nuclear accident and it was the Committee's intent to use the results of those ongoing assessments as an input to their evaluations. This information would be supplemented by additional studies consisting of the subject-related documents used at each reactor facility studied, and an on-site review of these reactor facilities by professional personnel within the Department of Energy, its operating contractors and independent consultants. 1 tab

  11. On inclusion of the Pauli principle in the quasi particle-phonon nuclear model

    International Nuclear Information System (INIS)

    Soloviev, V.G.

    1979-01-01

    The Pauli principle in odd-even, even-odd and even-even nuclei in the quasi particle-phonon nuclear model is considered. It is shown that the Pauli principle can excactly be taken into account. The exact and approximate secular equations are obtained for the wave function containing the one-quasi particle and quasi particle plus phonon components. The effect of the Pauli principle is discussed, when the wave function contains the one- and two-phonon components. In both the cases the poles are shifted in the secular equations and the quasi particle-phonon interaction terms are added. The number of quasi particles in the ground states is estimated. It is stated that in the majority of deformed nuclei the correlations in the ground states are small. It is shown that within the quasi particle-phonon nuclear model the calculations can be performed with the exact commutation relations

  12. Single-particle basis and translational invariance in microscopic nuclear calculations

    International Nuclear Information System (INIS)

    Ehfros, V.D.

    1977-01-01

    The approach to the few-body problem is considered which allows to use the simple single-particle basis without violation of the translation invariance. A method is proposed to solve the nuclear reaction problems in the single-particle basis. The method satisfies the Pauli principle and the translation invariance. Calculation of the matrix elements of operators is treated

  13. Use of instrumental nuclear activation methods in the study of particles from major air pollution sources

    International Nuclear Information System (INIS)

    Gordon, G.E.; Zoller, W.H.; Gladney, E.S.; Greenberg, R.R.

    1974-01-01

    Nuclear methods have been used effectively in the study of particles emitted by a coal-fired power plant and a municipal incinerator. In the coal-fired plant there is appreciable fractionation of only five of the observed elements. By contrast, particles from the incinerator are highly enriched in several trace elements

  14. Particle production from nuclear targets and the structure of hadrons

    International Nuclear Information System (INIS)

    Bialas, A.

    Production processes from nuclear targets allow studying interactions of elementary hadronic constituents in nuclear matter. The information thus obtained on the structure of hadrons and on the properties of hadronic constituents is presented. Both soft (low momentum transfer) and hard (high momentum transfer) processes are discussed. (author)

  15. Retinoids induce integrin-independent lymphocyte adhesion through RAR-α nuclear receptor activity

    Energy Technology Data Exchange (ETDEWEB)

    Whelan, Jarrett T.; Wang, Lei; Chen, Jianming; Metts, Meagan E.; Nasser, Taj A.; McGoldrick, Liam J. [Department of Biochemistry and Molecular Biology, The Brody School of Medicine at East Carolina University, Greenville, NC 27834 (United States); Bridges, Lance C., E-mail: bridgesl@ecu.edu [Department of Biochemistry and Molecular Biology, The Brody School of Medicine at East Carolina University, Greenville, NC 27834 (United States); East Carolina Diabetes and Obesity Institute, The Brody School of Medicine at East Carolina University, Greenville, NC 27834 (United States)

    2014-11-28

    Highlights: • Transcription and translation are required for retinoid-induced lymphocyte adhesion. • RAR activation is sufficient to induced lymphocyte cell adhesion. • Vitamin D derivatives inhibit RAR-prompted lymphocyte adhesion. • Adhesion occurs through a novel binding site within ADAM disintegrin domains. • RARα is a key nuclear receptor for retinoid-dependent lymphocyte cell adhesion. - Abstract: Oxidative metabolites of vitamin A, in particular all-trans-retinoic acid (atRA), have emerged as key factors in immunity by specifying the localization of immune cells to the gut. Although it is appreciated that isomers of retinoic acid activate the retinoic acid receptor (RAR) and retinoid X receptor (RXR) family of nuclear receptors to elicit cellular changes, the molecular details of retinoic acid action remain poorly defined in immune processes. Here we employ a battery of agonists and antagonists to delineate the specific nuclear receptors utilized by retinoids to evoke lymphocyte cell adhesion to ADAM (adisintegrin and metalloprotease) protein family members. We report that RAR agonism is sufficient to promote immune cell adhesion in both immortal and primary immune cells. Interestingly, adhesion occurs independent of integrin function, and mutant studies demonstrate that atRA-induced adhesion to ADAM members required a distinct binding interface(s) as compared to integrin recognition. Anti-inflammatory corticosteroids as well as 1,25-(OH){sub 2}D{sub 3}, a vitamin D metabolite that prompts immune cell trafficking to the skin, potently inhibited the observed adhesion. Finally, our data establish that induced adhesion was specifically attributable to the RAR-α receptor isotype. The current study provides novel molecular resolution as to which nuclear receptors transduce retinoid exposure into immune cell adhesion.

  16. Retinoids induce integrin-independent lymphocyte adhesion through RAR-α nuclear receptor activity

    International Nuclear Information System (INIS)

    Whelan, Jarrett T.; Wang, Lei; Chen, Jianming; Metts, Meagan E.; Nasser, Taj A.; McGoldrick, Liam J.; Bridges, Lance C.

    2014-01-01

    Highlights: • Transcription and translation are required for retinoid-induced lymphocyte adhesion. • RAR activation is sufficient to induced lymphocyte cell adhesion. • Vitamin D derivatives inhibit RAR-prompted lymphocyte adhesion. • Adhesion occurs through a novel binding site within ADAM disintegrin domains. • RARα is a key nuclear receptor for retinoid-dependent lymphocyte cell adhesion. - Abstract: Oxidative metabolites of vitamin A, in particular all-trans-retinoic acid (atRA), have emerged as key factors in immunity by specifying the localization of immune cells to the gut. Although it is appreciated that isomers of retinoic acid activate the retinoic acid receptor (RAR) and retinoid X receptor (RXR) family of nuclear receptors to elicit cellular changes, the molecular details of retinoic acid action remain poorly defined in immune processes. Here we employ a battery of agonists and antagonists to delineate the specific nuclear receptors utilized by retinoids to evoke lymphocyte cell adhesion to ADAM (adisintegrin and metalloprotease) protein family members. We report that RAR agonism is sufficient to promote immune cell adhesion in both immortal and primary immune cells. Interestingly, adhesion occurs independent of integrin function, and mutant studies demonstrate that atRA-induced adhesion to ADAM members required a distinct binding interface(s) as compared to integrin recognition. Anti-inflammatory corticosteroids as well as 1,25-(OH) 2 D 3 , a vitamin D metabolite that prompts immune cell trafficking to the skin, potently inhibited the observed adhesion. Finally, our data establish that induced adhesion was specifically attributable to the RAR-α receptor isotype. The current study provides novel molecular resolution as to which nuclear receptors transduce retinoid exposure into immune cell adhesion

  17. Nuclear export and import of human hepatitis B virus capsid protein and particles.

    Directory of Open Access Journals (Sweden)

    Hung-Cheng Li

    Full Text Available It remains unclear what determines the subcellular localization of hepatitis B virus (HBV core protein (HBc and particles. To address this fundamental issue, we have identified four distinct HBc localization signals in the arginine rich domain (ARD of HBc, using immunofluorescence confocal microscopy and fractionation/Western blot analysis. ARD consists of four tight clustering arginine-rich subdomains. ARD-I and ARD-III are associated with two co-dependent nuclear localization signals (NLS, while ARD-II and ARD-IV behave like two independent nuclear export signals (NES. This conclusion is based on five independent lines of experimental evidence: i Using an HBV replication system in hepatoma cells, we demonstrated in a double-blind manner that only the HBc of mutant ARD-II+IV, among a total of 15 ARD mutants, can predominantly localize to the nucleus. ii These results were confirmed using a chimera reporter system by placing mutant or wild type HBc trafficking signals in the heterologous context of SV40 large T antigen (LT. iii By a heterokaryon or homokaryon analysis, the fusion protein of SV40 LT-HBc ARD appeared to transport from nuclei of transfected donor cells to nuclei of recipient cells, suggesting the existence of an NES in HBc ARD. This putative NES is leptomycin B resistant. iv We demonstrated by co-immunoprecipitation that HBc ARD can physically interact with a cellular factor TAP/NXF1 (Tip-associated protein/nuclear export factor-1, which is known to be important for nuclear export of mRNA and proteins. Treatment with a TAP-specific siRNA strikingly shifted cytoplasmic HBc to nucleus, and led to a near 7-fold reduction of viral replication, and a near 10-fold reduction in HBsAg secretion. v HBc of mutant ARD-II+IV was accumulated predominantly in the nucleus in a mouse model by hydrodynamic delivery. In addition to the revised map of NLS, our results suggest that HBc could shuttle rapidly between nucleus and cytoplasm via a novel

  18. Particle emission in the hydrodynamical description of relativistic nuclear collisions

    International Nuclear Information System (INIS)

    Grassi, F.; Hama, Y.; Kodama, T.

    1994-09-01

    Continuous particle emission during the whole expansion of thermalized matter is studied and a new formula for the observed transverse mass spectrum is derived. In some limit, the usual emission at freeze out scenario (Cooper-Frye formula) may be recovered. In a simplified description of expansion, it is shown that continuous particle emission can lead to a sizable curvature in the pion transverse mass spectrum and parallel slopes for the various particles. These results are compared to experimental data. (author). 26 refs, 3 figs

  19. Proceedings of the Fifth Nuclear and Particle Physics Conference (NUPPAC-2005)

    International Nuclear Information System (INIS)

    Comsan, M.N.H.; Hanna, K.M.

    2006-08-01

    The publication's has been set up as a book of the conference of nuclear and particle physics, it consists of the following chapters (1) Plenary, Invited, Keynote Talks; (2) high energy physics; (3) nuclear scattering and reaction; (4) Relativistic and Quantum Physics; (5) neutron and reactor physics; (6) Nuclear Structure and Spectroscopy; (7) Detectors and Instrumentation; (8) computer codes and Simulation; (9) Radiation Measurements and Dosimetry; (10) Plasma and Fusion Physics

  20. Repulsive four-body interactions of α particles and quasistable nuclear α -particle condensates in heavy self-conjugate nuclei

    Science.gov (United States)

    Bai, Dong; Ren, Zhongzhou

    2018-05-01

    We study the effects of repulsive four-body interactions of α particles on nuclear α -particle condensates in heavy self-conjugate nuclei using a semianalytic approach, and find that the repulsive four-body interactions could decrease the critical number of α particles, beyond which quasistable α -particle condensate states can no longer exist, even if these four-body interactions make only tiny contributions to the total energy of the Hoyle-like state of 16O. Explicitly, we study eight benchmark parameter sets, and find that the critical number Ncr decreases by |Δ Ncr|˜1 -4 from Ncr˜11 with vanishing four-body interactions. We also discuss the effects of four-body interactions on energies and radii of α -particle condensates. Our study can be useful for future experiments to study α -particle condensates in heavy self-conjugate nuclei. Also, the experimental determination of Ncr will eventually help establish a better understanding on the α -particle interactions, especially the four-body interactions.

  1. Particle production in hot and dense nuclear matter

    International Nuclear Information System (INIS)

    Eklund, A.

    1992-08-01

    The charged particle production in heavy ion reactions at 200 A GeV has been studied for projectiles of 16 O and 32 S on targets of Al, Cu, Ag and Au. Up to 700 charged particles are measured in the pseudorapidity region -1.7 32 S+Au. The measured particle density is used to estimate the energy density attained in central collisions and gives a values of ≅2 GeV/fm 3 . This is close to the energy density predicted for the phase transition from hadronic matter to a quark-gluon plasma. To measure the large number of charged particle produced, finely granulated detector systems are employed. Streamer tube detectors with pad readout and large area, multi-step avalanche chambers with optical readout have been developed for the measurements. The widths of the pseudorapidity distributions of charged particles increase with decreasing centrality of the collision as well as with increasing mass of the target nucleus. This behaviour is assumed to be due to the target fragmentation. The Monte-Carlo model for nucleus-nucleus collisions, VENUS 3.11, which includes rescattering, is in reasonable agreement with the data. The yield of charged particles for central collisions of the heavy targets with 33 S is found to be proportional to the target mass, A, at target rapidity. At midrapidity it is approximately proportional to A 0.3 . At midrapidity the charged particle measurements are supplemented by measurements of the transverse energy. The dimensionless, normalized variances of the multiplicity and transverse energy distributions are, to a large extent, governed by the collision geometry. The change in the normalized variance when studying the charged particle distribution in a narrow angular region is explained as being of statistical nature. (au)

  2. A Medical Application of Nuclear Physics: Particle Radiotherapy with Protons

    Science.gov (United States)

    Farr, Jonathan B.

    2006-10-01

    Since the discovery of radiation, applications have been made to medicine. The advent of higher energy particle accelerators in the second half of the twentieth century enabled modern tele-therapy using relatively high energy x-rays and particles. Today mega-voltage (MV) x-rays are the most common modality of delivering high doses of potentially life saving radiation to a wide variety of disease, mostly malignant cancers. However, the maximum radiation dose that can be delivered is always limited by the effects to critical surrounding biologic structures. In many cases, due to their physical properties, ``heavy'' particle radiotherapy with protons and light ions may provide an advantage in this respect over MV x-rays allowing either a higher dose of radiation to be delivered to the volume or, for the same dose, reducing the concomitant damage to critical structures. This motivation, together with recent advances in particle therapy systems that are making the technology more readily available, is serving to grow the field of particle therapy. In particular, treatment with fast protons is becoming more widespread with over 20 facilities operating worldwide and more under construction. This presentation will provide an introduction to heavy particle therapy and additional details specifically on proton therapy.

  3. Studies of nuclear structure using neutrons and charged particles

    International Nuclear Information System (INIS)

    Roberson, N.R.

    1992-01-01

    This report discusses the following topics: fundamental symmetries in the nucleus; internucleon interactions; internucleon dynamics in very light nuclei; the many-nucleon problem; developments in electronuclear physics; and nuclear instruments and methods

  4. Charged particle-induced nuclear fission reactions – Progress and ...

    Indian Academy of Sciences (India)

    attracting the attention of the investigators right from the beginning of nuclear fis- ... the change from mass asymmetric division to symmetric division as A and N/Z values .... (a) Schematic of the fissioning nucleus showing the decision making.

  5. Modern hadron spectroscopy: a bridge between nuclear and particle physics.

    Science.gov (United States)

    Szczepaniak, A. P.

    2018-05-01

    In this talk I discuss aspects of hadron physics, which soon are expected to shed new light on the fundamental QCD phenomena. In the analysis of hadron reactions and their propertieds I emphasize similarities to the nuclear many body problem.

  6. Fukushima nuclear accident independent investigation commission by the National Diet of Japan

    International Nuclear Information System (INIS)

    Kurokawa, Kiyoshi

    2013-01-01

    After the Fukushima nuclear accident, Independent Investigation Commission (IIC) was firstly established in constitutional government by the National Diet of Japan. This article described recognition of its necessity, its setup process, its framework with start from almost zero and about 6 months period and time, its basic way to proceed investigation and several obstacles and hardships, significance of openness to the public, web's communication and simultaneous interpretation (transparency) and basic philosophy of the report. Further significance of Diet's IIC in the democratic system and evaluation of the report were added. As a problem of separation of three powers in Japan, specific recommendations to the legislation of IIC and their future evaluation, nation's governance system problem and social responsibility of scientists and others were also discussed. If Japan were not to be changed after the disaster, Japanese future might be unreliable. (T. Tanaka)

  7. Integral charged particle nuclear data bibliography: Literature scanned from April 11, 1987 through November 10, 1988

    International Nuclear Information System (INIS)

    Holden, N.E.; Ramavataram, S.

    1988-12-01

    This publication is the annual supplement to the first edition published in 1984. The primary goal of this publication has been to satisfy the need expressed by the Nuclear Reaction Data Center Network for a concise and comprehensive bibliography of integral charged-particle cross section data. The reader is referred to a partial list of other bibliographies relevant to charged-particle-induced reaction data and to ''A Source List of Nuclear Data Bibliographies, Compilations, and Evaluations'' for a more comprehensive list. Since this publication is not cumulative, earlier versions are also shown in this paper. This publication makes use of a modification to the database of the Nuclear Structure References (NSR) file. This modification allows the retrieval of integral charged particle nuclear data entries from the NSR file. In recent years, the presentation of various sections was changed, as a result of users' suggestions. The authors continue to welcome users' comments. 190 refs., 3 tabs

  8. Characterization of airborne plutonium-bearing particles from a nuclear fuel reprocessing plant

    International Nuclear Information System (INIS)

    Sanders, S.M. Jr.

    1977-11-01

    The elemental compositions, sizes, structures, and 239 Pu contents were determined for 299 plutonium-bearing particles isolated from airborne particles collected at various locations in the exhaust from a nuclear fuel reprocessing facility. These data were compared with data from natural aerosol particles. Most of the collected particles were composed of aggregates of crustal materials. Seven percent of the particles were organic and 3% were metallic, viz., iron, chromium, and nickel. High enrichment factors for titanium, manganese, chromium, nickel, zinc, and copper were evidence of the anthropic nature of some of the particles. The amount of plutonium in most particles was very small (less than one femtocurie of 239 Pu). Plutonium concentrations were determined by the fission track counting method. Only one particle contained sufficient plutonium for detection by electron microprobe analysis. This was a 1-μm-diameter particle containing 73% PuO 2 by weight (estimated to be 170 fCi of 239 Pu) in combination with Fe 2 O 3 and mica. The plutonium-bearing particles were generally larger than natural aerosols. The geometric mean diameter of those collected from the mechanical line exhaust point where plutonium is converted to the metal was larger than that of particles collected from the wet cabinet exhaust (13.7 μm vs. 4.6 μm). Particles from the mechanical line also contained more plutonium per particle than those from the wet cabinets

  9. Power politics: National energy strategies of the nuclear newly independent states of Armenia, Lithuania and Ukraine

    Science.gov (United States)

    Sabonis-Chafee, Theresa Marie

    The successor states of Armenia, Lithuania and Ukraine arrived at independence facing extraordinary challenges in their energy sectors. Each state was a net importer, heavily dependent on cheap energy supplies, mostly from Russia. Each state also inherited a nuclear power complex over which it had not previously exercised full control. In the time period 1991--1996, each state attempted to impose coherence on the energy sector, selecting a new course for the pieces it had inherited from a much larger, highly integrated energy structure. Each state attempted to craft national energy policies in the midst of severe supply shocks and price shocks. Each state developed institutions to govern its nuclear power sector. The states' challenges were made even greater by the fact that they had few political or economic structures necessary for energy management, and sought to create those structures at the same time. This dissertation is a systematic, non-quantitative examination of how each state's energy policies developed during the 1991--1996 time period. The theoretical premise of the analysis (drawn from Statist realism) is that systemic variables---regional climate and energy vulnerability---provide the best explanations for the resulting energy policy decisions. The dependent variable is defined as creation and reform of energy institutions. The independent variables include domestic climate, regional climate, energy vulnerability and transnational assistance. All three states adopted rhetoric and legislation declaring energy a strategic sector. The evidence suggests that two of the states, Armenia and Lithuania, which faced tense regional climates and high levels of energy vulnerability, succeeded in actually treating energy strategically, approaching energy as a matter of national security or "high politics." The third state, Ukraine, failed to do so. The evidence presented suggests that the systemic variables (regional climate and energy vulnerability) provided a

  10. Model independent particle mass measurements in missing energy events at hadron colliders

    Science.gov (United States)

    Park, Myeonghun

    2011-12-01

    This dissertation describes several new kinematic methods to measure the masses of new particles in events with missing transverse energy at hadron colliders. Each method relies on the measurement of some feature (a peak or an endpoint) in the distribution of a suitable kinematic variable. The first method makes use of the "Gator" variable s min , whose peak provides a global and fully inclusive measure of the production scale of the new particles. In the early stage of the LHC, this variable can be used both as an estimator and a discriminator for new physics over the standard model backgrounds. The next method studies the invariant mass distributions of the visible decay products from a cascade decay chain and the shapes and endpoints of those distributions. Given a sufficient number of endpoint measurements, one could in principle attempt to invert and solve for the mass spectrum. However, the non-linear character of the relevant coupled quadratic equations often leads to multiple solutions. In addition, there is a combinatorial ambiguity related to the ordering of the decay products from the cascade decay chain. We propose a new set of invariant mass variables which are less sensitive to these problems. We demonstrate how the new particle mass spectrum can be extracted from the measurement of their kinematic endpoints. The remaining methods described in the dissertation are based on "transverse" invariant mass variables like the "Cambridge" transverse mass MT2, the "Sheffield" contrasverse mass MCT and their corresponding one-dimensional projections MT2⊥, M T2||, MCT⊥ , and MCT|| with respect to the upstream transverse momentum U⃗T . The main advantage of all those methods is that they can be applied to very short (single-stage) decay topologies, as well as to a subsystem of the observed event. The methods can also be generalized to the case of non-identical missing particles, as demonstrated in Chapter 7. A complete set of analytical results for the

  11. Multiparticle correlations and identical particle effects in the independent cluster emission model

    International Nuclear Information System (INIS)

    Ranft, J.

    1977-01-01

    In the nucleon approach to phenomenological applications, the model is compared to many different kinds of experimental data. The comparison indicates, that the model is qualitatively consistent with all available data. Analysis indicates, that identical particle effects due to the Bose statistics are present in data on joint rapidity-asimuthal correlations near Δy=ΔPHI=0. A new approach to this problem is the uncorrelated jet model with the Bose statistics. This model confirms the previous results. Furthermore, taking isospin conservation into account, the Bose correlations are predicted in π + π - channels, which should be most easily detectable in the decay of heavy resonances J/PSI

  12. Nuclear track detectors for charged particles and neutrons

    International Nuclear Information System (INIS)

    Tommasino, L.

    2006-01-01

    It was with great emotion that I accepted to be a guest speaker to this memorial section dedicated to my old-time friend, Prof. Radomir Ilic. In addition to being one of the most outstanding scientists in the field of nuclear tracks, Prof. Radomir Ilic has been always highly acclaimed by the scientific community for his enthusiasm, his warm friendship, and his great vitality. Through his successful editorial activities, Prof. Ilic has proved to be very able to address the field of nuclear tracks to very wide audiences with special regards to young students. It was here in Portoroz, that Prof. Radomir Ilic was our host as the organiser of the 21st International Conference on Nuclear Tracks in Solids. All the participants have great memories of this very successful international conference. For all these reasons, the 2006 edition of the International Conference on Nuclear Energy for new Europe, with its wide audience and its venue at Portoroz, can be considered as one of the most appropriate forum for the memorial lecture of Prof. Radomir Ilic. The present paper will be dealing with the solid state nuclear track detectors-SSNTDs and their successful applications for the measurements of cosmic-ray-neutrons and terrestrial radioactivity, namely radon. (author)

  13. A history of nuclear transmutations by natural alpha particles

    International Nuclear Information System (INIS)

    Leone, Matteo

    2005-01-01

    A systematic account of the use of alpha particles up to the 1930s for promoting the disintegration of atoms is here provided. As will be shown, a number of different radium family alpha sources were used in the experiments that led to the discoveries of the proton (Rutherford E 1919 Phil. Mag. 37 581-7) and neutron (Chadwick J 1932 Nature 129 312). The reasons leading to the employment of a particular alpha particle source, as well as the relationship between these sources and the available methods of recording, will be closely addressed

  14. An attempt to observe directly beauty particles in nuclear emulsions

    International Nuclear Information System (INIS)

    Albanese, J.P.; Arnold, R.; Matteuzzi, C.; Musset, P.; Piuz, F.; Poulard, G.; Price, M.J.; Ramello, L.; Sletten, H.; Allasia, D.; Bisi, V.; Gamba, D.; Marzari-Chiesa, A.; Riccati, L.; Romero, A.; Armenise, N.; Calicchio, M.; Erriquez, O.; Lavopa, P.; Maggi, G.; Muciaccia, M.T.; Natali, S.; Nuzzo, S.; Romano, F.; Ruggieri, F.; Baroni, G.; Di Ciaccio, L.; Di Liberto, S.; Manfredini, A.; Meddi, F.; Petrera, S.; Romano, G.; Rosa, G.; Santonico, R.; Sebastiani, F.; Barth, M.; Bertrand, D.; Bertrand-Coremans, G.; Roosen, R.; Sacton, J.; Schorochoff, G.; Wickens, J.; Breslin, A.C.; Montwill, A.; O'Connor, A.; Davis, D.G.; Davis, D.H.; Downes, J.K.; Duff, B.G.; Esten, M.J.; Gjerpe, I.; Heymann, F.F.; Imrie, D.C.; Lush, G.J.; Tovee, D.N.; Hazama, M.; Isokane, Y.; Tsuneoka, Y.; Maeda, Y.; Tasaka, S.

    1983-01-01

    An attempt at the direct observation of the cascade decay of beauty particles, produced by π - of 350 GeV/c leading to 3 muons or 4 muons in the final state, has been made in an emulsion/counter hybrid experiment at CERN. Under the assumption that the lifetime of beauty particles is of the order of 10 - 13 s the non-observation of any candidates provides an upper limit for beauty production of approx.=90 nb at the 90% confidence level. (orig.)

  15. Nuclear Waste Removal Using Particle Beams Incineration with Fast Neutrons

    CERN Document Server

    Revol, Jean Pierre Charles

    1997-01-01

    The management of nuclear waste is one of the major obstacles to the acceptability of nuclear power as a main source of energy for the future. TARC, a new experiment at CERN, is testing the practicality of Carlo Rubbia's idea to make use of Adiabatic Resonance Crossing to transmute long-lived fission fragments into short-lived or stable nuclides. Spallation neutrons produced in a large Lead assembly have a high probability to be captured at the energies of cross-section resonances in elements such as 99Tc, 129I, etc. An accelerator-driven sub-critical device using Thorium (Energy Amplifier) would be very effective in eliminating TRansUranic elements which constitute the most dangerous part of nuclear waste while producing from it large amounts of energy. In addition, such a system could transform, at a high rate and little energetic cost, long-lived fission fragments into short-lived elements.

  16. Calculating tracer currents through narrow ion channels: Beyond the independent particle model.

    Science.gov (United States)

    Coalson, Rob D; Jasnow, David

    2018-06-01

    Discrete state models of single-file ion permeation through a narrow ion channel pore are employed to analyze the ratio of forward to backward tracer current. Conditions under which the well-known Ussing formula for this ratio hold are explored in systems where ions do not move independently through the channel. Building detailed balance into the rate constants for the model in such a way that under equilibrium conditions (equal rate of forward vs. backward permeation events) the Nernst Equation is satisfied, it is found that in a model where only one ion can occupy the channel at a time, the Ussing formula is always obeyed for any number of binding sites, reservoir concentrations of the ions and electric potential difference across the membrane which the ion channel spans, independent of the internal details of the permeation pathway. However, numerical analysis demonstrates that when multiple ions can occupy the channel at once, the nonequilibrium forward/backward tracer flux ratio deviates from the prediction of the Ussing model. Assuming an appropriate effective potential experienced by ions in the channel, we provide explicit formulae for the rate constants in these models. © 2018 IOP Publishing Ltd.

  17. Independent modelling in SSM's licensing review of a spent nuclear fuel repository

    International Nuclear Information System (INIS)

    Xu, Shulan; Dverstorp, Bjoern; Norden, Maria

    2014-01-01

    In 2011 the Swedish Nuclear Fuel and Waste Management Co. (SKB) submitted a license application for construction of a geological repository for spent nuclear fuel at Forsmark. SKB's disposal method, the KBS-3 method, involves disposing of the spent nuclear fuel in cast iron canisters with an outer layer of 5 cm copper. The canisters will be placed in vertical deposition holes at approximately 500 m depths in crystalline bedrock. Each canister is surrounded by a buffer of swelling bentonite clay. The repository is designed to accommodate 6 000 canisters, corresponding to 12 000 tonnes of spent nuclear fuel. The license application is supported by a post-closure safety assessment, SR-Site. Along with other parts of the application, SR-Site is currently being reviewed by the Swedish Radiation Safety Authority (SSM). The main method for review of SKB's licensing documentation is document review carried out by SSM, supported by SSM's external experts. However, SSM's document review is also supported by regulatory modelling, technical reviews of SKB's quality assurance programme and consideration of external review comments partly from two broad national consultations and an international peer review organised by the OECD's Nuclear Energy Agency (NEA, 2012). SSM's review is divided into three main phases: the initial review phase, the main review phase and the reporting phase. The overall goal of the initial review phase is to achieve a broad coverage of SR-Site and its supporting references and in particular to identify the need for complementary information and clarifications to be provided by SKB, as well as to identify critical review issues that require a more comprehensive treatment in the main review phase. SSM completed the initial review phase at the end of 2012. During the initial review phase SSM has identified a number of issues requiring either clarifications, complementary information from SKB or further in-depth review by SSM. Important issues include the

  18. Radioactive particles after different nuclear events in the USSR (overview and modern data)

    Energy Technology Data Exchange (ETDEWEB)

    Gordeev, S.K.; Stukin, E.D.; Kvasnikova, E.V. [Institute of Global Climate and Ecology, Moscow (Russian Federation)

    2004-07-01

    Institute of Global Climate and Ecology participated in all stages of investigations concerning spreading of the radioactive particles formed after nuclear explosions. Since 1963 the radioactive particles from the surface nuclear explosions on the Semipalatinsk Test Site were investigated. Since 1964 the study of the environmental contamination from the underground nuclear explosions (including the cratering nuclear explosions) was carried out. Simultaneously the secondary radioactive aerosols released into the atmosphere from ventilated underground explosions were investigated. Since 1986 the forming and spreading of the radioactive aerosols from Chernobyl accident was studied. An overview of retrospective data will be presented. For example, the fragmentation radionuclides {sup 90}Sr, {sup 137}Cs and {sup 155}Eu, radionuclides induced by neutrons {sup 60}Co, {sup 152}Eu, {sup 154}Eu and transuranium radionuclides {sup 238}Pu, {sup 239+240}Pu and {sup 241}Am were estimated in 15 particles of August, 29, 1949 explosion using the semiconductor spectrometry and radiochemical analysis. Data collection include the samples taken on local traces of ground and underground excavation nuclear explosions, this information will be added by the modern data from soil samples near '1004' explosion (lake Chagan), October 2003. The results of comparison of radionuclide fractionation in the radioactive particles in slag from cratering nuclear explosions and in melt samples will be presented. Main results obtained under the IAEA Research Contract no. 11468. (author)

  19. An empirical approach to the theory of particle and nuclear ...

    Indian Academy of Sciences (India)

    Nuclear Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, ... brief review of some interesting consequences is presented here. ... generalization of the Gutzwiller trace formula for field theories may lead to a systematic semiclassi- ... There are two important gaps in the line, first being between Т.

  20. Symposium on nuclear particle accelerators in medicine: abstracts

    International Nuclear Information System (INIS)

    1986-01-01

    This symposium deals with the cyclotron production of radiopharmaceuticals and the application of radionuclides and -pharmaceuticals produced this way. The use of positron emitters in nuclear medicine medical physics and radiobiology are discussed as well as radiotherapy and all the aspects of neutron radiation and dosimetry of neutron therapy

  1. On the momentum distribution of particles participating in nuclear ...

    Indian Academy of Sciences (India)

    Nuclear stopping is studied as a function of incident energy and charge of the ... Low and intermediate energy heavy-ion reactions; breakup and momentum ... it to be highly sensitive towards the N–N cross-section and weakly towards different ...

  2. Skin Dose Assessment by Hot Particles in Domestic Nuclear Power Plant

    International Nuclear Information System (INIS)

    Choi, Bo Yeol; Cho, Woon Kap; Lee, Jai Ki

    2009-01-01

    Since a contamination event by hot particles happened due to damaged nuclear fuel at a nuclear power plant (NPP) in the 1980's, skin exposure resulted from hot particles has gotten considerable attention from all the radiation workers in the nuclear industry. In particular, contamination incident caused by hot particles which happened at a NPP in Susquehanna proved that there existed hot particles with the radioactivity of 0.7 GBq, 0.78 GBq, and even 2.78 GBq at maximum. One of these particles was found on a worker's shoe and gave out a dose of 170 mSv. Although there has been no contamination event reported in domestic NPPs which are caused by hot particles, it is hard to conclude that there is no possibility of such contamination for radiation workers. The contaminated samples employed in this study were taken from local NPPs and supposes a case of a worker's skin contaminated by hot particles to evaluate the dose provided to the worker's skin

  3. Independent body for surveillance over nuclear safety in the Slovak Republic established

    International Nuclear Information System (INIS)

    Zlatnansky, J.

    1994-01-01

    The position, role, tasks and organizational structure of the Nuclear Safety Authority of the Slovak Republic are outlined. The Authority is responsible for state surveillance over nuclear safety of nuclear facilities including surveillance over radioactive waste management, over spent fuel management and other stages of the fuel cycle, as well as over nuclear materials including their accountancy and recording. The body is also responsible for assessing projects within the nuclear energy use programme and the quality of selected nuclear technological facilities and instrumentation, as well as for Slovak commitments and obligations under international agreements concerned with nuclear safety of nuclear facilities and with radioactive wastes. (J.B.). 1 fig

  4. Method to produce carbon-cladded nuclear fuel particles

    International Nuclear Information System (INIS)

    Sturge, D.W.; Meaden, G.W.

    1978-01-01

    In the method charges of micro-spherules of fuel element are designed to have two carbon layers, whereby a one aims to achieve a uniform granulation (standard measurement). Two drums are used for this purpose connected behind one another. The micro-spherules coated with the first layer (phenolformaldehyde resin coated graphite particles) leave the first drum and enter the second one. Following the coating with a second layer, the micro-spherules are introduced into a grain size separator. The spherules that are too small are directly recycled into the second drum and those ones that are too large are recycled into the first drum after removing the graphite layers. The method may also be applied to metal cladded particles to manufacture cermet fuels. (RW) [de

  5. Overview of insoluble radioactive cesium particles emitted from the Fukushima Dai-ichi Nuclear Power Station

    Science.gov (United States)

    Satou, Yukihiko

    2017-04-01

    In the early stage of the Fukushima Dai-ichi Nuclear Power Station (F1NPS) accident, number of spot type contamination has been observed in computed autoradiography (Kashimura 2013, Shibata 2013, Satou 2014). It's means presence of radioactive particles, however, insoluble cesium particle was overlooked because cesium, which is dominant radioactive element in the accident, becomes ionized in the environment. Adachi et al. (2013) showed presence of cesium (Cs)-bearing particles within air dust sample collected at Tsukuba, 170 km south from the Fukushima site, in midnight of 14 to morning of 15 March 2011. These particles were micrometer order small particles and Cs was could be detectable as element using an energy dispersive X-ray spectroscopy (EDX). However, other radioactive elements such as Co-60, Ru-103 and uranium, which were dominant element of radioactive particles delivered from Chernobyl accident, could not detected. Abe et al. (2014) employed a synchrotron radiation (SR)-micro(μ)-X-ray analysis to the Cs-bearing particles, and they were concluded that (1) contained elements derived from nuclear fission processes and from nuclear reactor and fuel materials; (2) were amorphous; (3) were highly oxidized; and (4) consisted of glassy spherules formed from a molten mixture of nuclear fuel and reactor material. In addition, Satou et al. (2016) and Yamaguchi et al. (2016) disclosed that silicate is main component of Cs-bearing particles. Satou et al. (2015) discovered two types of radioactive particles from soil samples collected in the vicinity of the F1NPS. These particles were remained in the natural environment more than four years, silicate is main component in common of each group particles. Group A particles were very similar to Cs-bearing particles reported by Adachi et al. except particle shape. On the other hand, group B is big particles found in north area from the F1NPS, and the strongest particles contained 20 kBq of Cs-137 within a particle

  6. Measurement of particle size distribution and mass concentration of nuclear fuel aerosols

    International Nuclear Information System (INIS)

    Pickering, S.

    1982-01-01

    The particle size distribution and particle mass concentration of a nuclear fuel aerosol is measured by admitting the aerosol into a vertically-extending container, positioning an alpha particle detector within the container so that its window is horizontal and directed vertically, stopping the admission of aerosol into the container, detecting the alpha-activity of the particles of the aerosol sedimenting onto the detector window (for example in a series of equal time intervals until a constant level is reached), and converting the alpha-activity measurements into particle size distribution and/or particle mass concentration measurements. The detector is attached to a pivotted arm and by raising a counterweight can be lowered from the container for cleaning. (author)

  7. Chlorine gas processing of oxide nuclear fuel particles containing thorium

    International Nuclear Information System (INIS)

    Knotik, K.; Bildstein, H.; Falta, G.; Wagner, H.

    Experimental studies on the chloride extraction and separation of U and Th from coated Th--U oxide particles are reported. After a description of the chlorination equipment and the experimental procedures, the results are discussed. The yield of U is determined as a function of the reaction temperature. The results of a thermogravimetric analysis of the chlorination of uranium carbide and thorium carbides are reported and used to establish the reaction mechanism for the chlorination

  8. Quasifree (p, 2p) Reactions on Oxygen Isotopes: Observation of Isospin Independence of the Reduced Single-Particle Strength.

    Science.gov (United States)

    Atar, L; Paschalis, S; Barbieri, C; Bertulani, C A; Díaz Fernández, P; Holl, M; Najafi, M A; Panin, V; Alvarez-Pol, H; Aumann, T; Avdeichikov, V; Beceiro-Novo, S; Bemmerer, D; Benlliure, J; Boillos, J M; Boretzky, K; Borge, M J G; Caamaño, M; Caesar, C; Casarejos, E; Catford, W; Cederkall, J; Chartier, M; Chulkov, L; Cortina-Gil, D; Cravo, E; Crespo, R; Dillmann, I; Elekes, Z; Enders, J; Ershova, O; Estrade, A; Farinon, F; Fraile, L M; Freer, M; Galaviz Redondo, D; Geissel, H; Gernhäuser, R; Golubev, P; Göbel, K; Hagdahl, J; Heftrich, T; Heil, M; Heine, M; Heinz, A; Henriques, A; Hufnagel, A; Ignatov, A; Johansson, H T; Jonson, B; Kahlbow, J; Kalantar-Nayestanaki, N; Kanungo, R; Kelic-Heil, A; Knyazev, A; Kröll, T; Kurz, N; Labiche, M; Langer, C; Le Bleis, T; Lemmon, R; Lindberg, S; Machado, J; Marganiec-Gałązka, J; Movsesyan, A; Nacher, E; Nikolskii, E Y; Nilsson, T; Nociforo, C; Perea, A; Petri, M; Pietri, S; Plag, R; Reifarth, R; Ribeiro, G; Rigollet, C; Rossi, D M; Röder, M; Savran, D; Scheit, H; Simon, H; Sorlin, O; Syndikus, I; Taylor, J T; Tengblad, O; Thies, R; Togano, Y; Vandebrouck, M; Velho, P; Volkov, V; Wagner, A; Wamers, F; Weick, H; Wheldon, C; Wilson, G L; Winfield, J S; Woods, P; Yakorev, D; Zhukov, M; Zilges, A; Zuber, K

    2018-02-02

    Quasifree one-proton knockout reactions have been employed in inverse kinematics for a systematic study of the structure of stable and exotic oxygen isotopes at the R^{3}B/LAND setup with incident beam energies in the range of 300-450  MeV/u. The oxygen isotopic chain offers a large variation of separation energies that allows for a quantitative understanding of single-particle strength with changing isospin asymmetry. Quasifree knockout reactions provide a complementary approach to intermediate-energy one-nucleon removal reactions. Inclusive cross sections for quasifree knockout reactions of the type ^{A}O(p,2p)^{A-1}N have been determined and compared to calculations based on the eikonal reaction theory. The reduction factors for the single-particle strength with respect to the independent-particle model were obtained and compared to state-of-the-art ab initio predictions. The results do not show any significant dependence on proton-neutron asymmetry.

  9. Nuclear fuel element containing particles of an alloyed Zr, Ti, and Ni getter material

    International Nuclear Information System (INIS)

    Grossman, L.N.; Levin, H.A.

    1975-01-01

    A nuclear fuel element for use in the core of a nuclear reactor is disclosed. The nuclear fuel element has disposed therein an alloy having the essential components of nickel, titanium and zirconium, and the alloy reacts with water, water vapor and reactive gases at reactor ambient temperatures. The alloy is disposed in the plenum of the fuel element in the form of particles in a hollow gas permeable container having a multiplicity of openings of size smaller than the size of the particles. The openings permit gases and liquids entering the plenum to contact the particles of alloy. The container is preferably held in the spring in the plenum of the fuel element. (Official Gazette)

  10. Analysis in nuclear power accident emergency based on random network and particle swarm optimization

    International Nuclear Information System (INIS)

    Gong Dichen; Fang Fang; Ding Weicheng; Chen Zhi

    2014-01-01

    The GERT random network model of nuclear power accident emergency was built in this paper, and the intelligent computation was combined with the random network based on the analysis of Fukushima nuclear accident in Japan. The emergency process was divided into the series link and parallel link, and the parallel link was the part of series link. The overall allocation of resources was firstly optimized, and then the parallel link was analyzed. The effect of the resources for emergency used in different links was analyzed, and it was put forward that the corresponding particle velocity vector was limited under the condition of limited emergency resources. The resource-constrained particle swarm optimization was obtained by using velocity projection matrix to correct the motion of particles. The optimized allocation of resources in emergency process was obtained and the time consumption of nuclear power accident emergency was reduced. (authors)

  11. The importance of independent research and evaluation in assessing nuclear fuel cycle and waste management facility safety

    International Nuclear Information System (INIS)

    Downing, Walter D.; Patrick, Wesley C.; Sagar, Budhi

    2009-01-01

    In 1987, the United States Nuclear Regulatory Commission (NRC) established at Southwest Research Institute (SwRI) a federally funded research and development center. Known as the Center for Nuclear Waste Regulatory Analyses (CNWRA), its overall mission is to provide NRC with an independent assessment capability on technical and regulatory issues related to a potential geologic repository for spent nuclear fuel and high-level radioactive waste, as well as interim storage and other nuclear fuel-cycle facilities. For more than 20 years, the CNWRA has supported NRC through an extensive pre-licensing period of establishing the framework of regulations and guidance documents, developing computer codes and other review tools, and conducting independent laboratory, field, and numerical analyses. In June 2008, the United States Department of Energy (DOE) submitted a license application and final environmental impact statement to NRC seeking authorization to construct the nation's first geologic repository at Yucca Mountain, Nevada. The CNWRA will assist NRC in conducting a detailed technical review to critically evaluate the DOE license application to assess whether the potential repository has been designed and can be constructed and operated to safely dispose spent nuclear fuel and high-level radioactive waste. NRC access to independent, unbiased, technical advice from the CNWRA is an important aspect of the evaluation process. This paper discusses why an independent perspective is important when dealing with nuclear fuel cycle and waste management issues. It addresses practical considerations such as avoiding conflicts of interest while at the same time maintaining a world-class research program in technical areas related to the nuclear fuel cycle. It also describes an innovative approach for providing CNWRA scientists and engineers a creative outlet for professional development through an internally funded research program that is focused on future nuclear waste

  12. Electromagnetic polarisabilities of the proton in an independent particle potential model

    International Nuclear Information System (INIS)

    Barik, N.; Panda, A.R.

    1996-01-01

    We consider the electric and magnetic polarisabilities of the proton including the valence quark as well as pion dressing effects in an independent quark model with an effective scalar-vector harmonic potential which renders the solvability of relativistic Dirac equations for confined quarks, and has in fact acted as an alternative to the cloudy bag model (CBM). This model which has been applied successfully to a variety of hadronic problems is also observed here to yield the electromagnetic polarisabilities of the proton satisfactorily without any free parameters. The electric and magnetic polarisabilities, including valence quark core and pion cloud effects, obtained here as anti α P =14.074.10 -4 fm 3 and anti β P =3.155.10 -4 fm 3 , are well within the uncertainties of their experimental measurements of (10.9±2.2±1.4).10 -4 fm 3 and (3.3±2.2±1.4).10 -4 fm 3 , respectively and are also in agreement with other model estimations. (orig.)

  13. Electromagnetic polarisabilities of the proton in an independent particle potential model

    Energy Technology Data Exchange (ETDEWEB)

    Barik, N [Utkal Univ., Bhubaneswer (India). P.G. Dept. of Phys.; Dash, B K [Utkal Univ., Bhubaneswer (India). P.G. Dept. of Phys.; Das, P [Department of Physics, Kendrapara College, Kendrapara-754211 (India); Panda, A R [Department of Physics, Kendrapara College, Kendrapara-754211 (India)

    1996-08-19

    We consider the electric and magnetic polarisabilities of the proton including the valence quark as well as pion dressing effects in an independent quark model with an effective scalar-vector harmonic potential which renders the solvability of relativistic Dirac equations for confined quarks, and has in fact acted as an alternative to the cloudy bag model (CBM). This model which has been applied successfully to a variety of hadronic problems is also observed here to yield the electromagnetic polarisabilities of the proton satisfactorily without any free parameters. The electric and magnetic polarisabilities, including valence quark core and pion cloud effects, obtained here as anti {alpha}{sub P}=14.074.10{sup -4} fm{sup 3} and anti {beta}{sub P}=3.155.10{sup -4} fm{sup 3}, are well within the uncertainties of their experimental measurements of (10.9{+-}2.2{+-}1.4).10{sup -4} fm{sup 3} and (3.3{+-}2.2{+-}1.4).10{sup -4} fm{sup 3}, respectively and are also in agreement with other model estimations. (orig.).

  14. Intermittency in the particle production and in the nuclear multifragmentation

    International Nuclear Information System (INIS)

    Bozek, P.; Ploszajczak, M.

    1991-01-01

    Intermittency is a manifestation of scale invariance and randomness in physical systems. Intermittency in relativistic heavy-ion collisions and, in particular, the projectile dependence, multiplicity dependence and source-size dependence are discussed in the frame of the model of spatio-temporal intermittency. Moreover, recent theoretical results in intermittency studies of the nuclear multifragmentation are presented. (author) 35 refs., 4 figs., 1 tab

  15. Charged particle radioisotope production at Instituto de Engenharia Nuclear - IEN

    International Nuclear Information System (INIS)

    Lemos Junior, O.F.

    1992-05-01

    A variable energy isochronous cyclotron (CV-28) was installed in 1974 at the Instituto de Engenharia Nuclear in Rio de Janeiro, with the purpose, among others, of irradiating suitable targets to produce radioisotopes for medical diagnostic studies. This papers is an overview of the work done in the last two decades and reports the present status on the production of iodine-123 and gallium-67. (author)

  16. Nuclear planetology: understanding planetary mantle and crust formation in the light of nuclear and particle physics

    Science.gov (United States)

    Roller, Goetz

    2017-04-01

    conceptual model constraining the evolution of a rocky planet like Earth or Mercury from a stellar precursor of the oldest population to a Fe-C BLD, shifting through different spectral classes in a HR diagram after massive decompression and tremendous energy losses. In the light of WD/BLD cosmochronology [1], solar system bodies like Earth, Mercury and Moon are regarded as captured interlopers from the Galactic bulge, Earth and Moon possibly representing remnants of an old binary system. Such a preliminary scenario is supported by similar ages obtained from WD's for the Galactic halo [1] and, independently, by means of 187Re-232Th-238U nuclear geochronometry [3, 4], together with recent observations extremely metal-poor stars from the cosmic dawn in the bulge of the Milky Way [8]. This might be further elucidated in the near future by Th/U cosmochronometry based upon a nuclear production ratio Th/U = 0.96 [9] and additionally by means of a newly developed nucleogeochronometric age dating method for stellar spectroscopy [9-11]. The model shall stimulate geochemical data interpretation from a different perspective, to constrain the evolution and differentiation of planetary or lunar crusts and mantles in general. [1] Fontaine et al. (2001), Public. Astron. Soc. of the Pacific 113, 409-435. [2] Roller (2015), Abstract T34B-0407, AGU Spring Meeting 2015. [3] Roller (2016), Goldschmidt Conf. Abstr. 26, 2642. [4] Roller (2015), Goldschmidt Conf. Abstr. 25, 2672. [5] Roller (2015), Geophys. Res. Abstr. 18, EGU2016-33. [6] Arevalo et al. (2010), Chem. Geol. 271, 70-85. [7] Roller (2015), Geophys. Res. Abstr. 17, EGU2015-2399. [8] Howes et al. (2015), Nature 527, 484-487. [9] Roller (2016), JPS Conf. Proc., Nuclei in the Cosmos (NIC XIV), Niigata, Japan, subm. (NICXIV-001); NICXIV Abstr. #1570244284. [10] Roller (2016), JPS Conf. Proc., Nuclei in the Cosmos (NIC XIV), Niigata, Japan, subm. (NICXIV-002); NICXIV Abstr. #1570244285. [11] Roller (2016), JPS Conf. Proc., Nuclei in the

  17. Development of utility system of charged particle Nuclear Reaction Data on Unified Interface

    International Nuclear Information System (INIS)

    Aoyama, Shigeyoshi; Ohbayashi, Yosihide; Kato, Kiyoshi; Masui, Hiroshi; Ohnishi, Akira; Chiba, Masaki

    1999-01-01

    We have developed a utility system, WinNRDF, for a nuclear charged particle reaction data of NRDF (Nuclear Reaction Data File) on a unified interface of Windows95, 98/NT. By using the system, we can easily search the experimental data of a charged particle reaction in NRDF and also see the graphic data on GUI (Graphical User Interface). Furthermore, we develop a mechanism of making a new index of keywords in order to include the time developing character of the NRDF database. (author)

  18. Introduction to the study of particle accelerators. Atomic, nuclear and high energy physics for engineers

    International Nuclear Information System (INIS)

    Warnecke, R.R.

    1975-01-01

    This book is destined for engineers taking part in the design building and running of nuclear physics and high-energy physics particle accelerators. It starts with some notions on the theory of relativity, analytical and statistical mechanics and quantum mechanics. An outline of the properties of atomic nuclei, the collision theory and the elements of gaseous plasma physics is followed by a discussion on elementary particles: characteristic parameters, properties, interactions, classification [fr

  19. Scattering in particle-hole space: simple approximations to nuclear RPA calculations in the continuum

    International Nuclear Information System (INIS)

    Toledo Piza, A.F.R. de.

    1987-01-01

    The Random Phase Approximation (RPA) treatment of nuclear small amplitude vibrations including particle-hole continua is handled in terms of previously developed techniques to treat single-particle resonances in a reaction theoretical framework. A hierarchy of interpretable approximations is derived and a simple working approximation is proposed which involves a numerical effort no larger than that involved in standard, discrete RPA calculations. (Author) [pt

  20. Multigroup constants for charged particle elastic nuclear (plus interference) scattering of light isotopes

    International Nuclear Information System (INIS)

    Cullen, D.E.; Perkins, S.T.

    1977-01-01

    Multi-group averaged reaction rates and transfer matrices were calculated for charged particle induced elastic nuclear (plus interference) scattering. Results are presented using a ten group structure for all twenty-five permutations of projectile and target for the following charged particles: p, d, t, 3 He and alpha. Transfer matrices are presented in a simplified form for both incident projectile and the knock-ons; these matrices explicitly conserve energy

  1. Effects of nuclear structure in the spin-dependent scattering of weakly interacting massive particles

    Science.gov (United States)

    Nikolaev, M. A.; Klapdor-Kleingrothaus, H. V.

    1993-06-01

    We present calculations of the nuclear from factors for spin-dependent elastic scattering of dark matter WIMPs from123Te and131Xe isotopes, proposed to be used for dark matter detection. A method based on the theory of finite Fermi systems was used to describe the reduction of the single-particle spin-dependent matrix elements in the nuclear medium. Nucleon single-particle states were calculated in a realistic shell model potential; pairing effects were treated within the BCS model. The coupling of the lowest single-particle levels in123Te to collective 2+ excitations of the core was taken into account phenomenologically. The calculated nuclear form factors are considerably less then the single-particle ones for low momentum transfer. At high momentum transfer some dynamical amplification takes place due to the pion exchange term in the effective nuclear interaction. But as the momentum transfer increases, the difference disappears, the momentum transfer increases and the quenching effect disappears. The shape of the nuclear form factor for the131Xe isotope differs from the one obtained using an oscillator basis.

  2. Effects of nuclear structure in the spin-dependent scattering of weakly interacting massive particles

    International Nuclear Information System (INIS)

    Nikolaev, M.A.; Klapdor-Kleingrothaus, H.V.

    1993-01-01

    We present calculations of the nuclear from factors for spin-dependent elastic scattering of dark matter WIMPs from 123 Te and 131 Xe isotopes, proposed to be used for dark matter detection. A method based on the theory of finite Fermi systems was used to describe the reduction of the single-particle spin-dependent matrix elements in the nuclear medium. Nucelon single-particle states were calculated in a realistic shell model potential; pairing effects were treated within the BCS model. The coupling of the lowest single-particle levels in 123 Te to collective 2 + excitations of the core was taken into account phenomenologically. The calculated nuclear form factors are considerably less then the single-particle ones for low momentum transfer. At high momentum transfer some dynamical amplification takes place due to the pion exchange term in the effective nuclear interaction. But as the momentum transfer increases, the difference disappears, the momentum transfer increases and quenching effect disappears. The shape of the nuclear form factor for the 131 Xe isotope differs from the one obtained using an oscillator basis. (orig.)

  3. Exploratory study of nuclear reaction data utility framework of Japan charged particle reaction data group (JCPRG)

    International Nuclear Information System (INIS)

    Masui, Hiroshi; Ohnishi, Akira; Kato, Kiyoshi; Ohbayasi, Yosihide; Aoyama, Shigeyoshi; Chiba, Masaki

    2002-01-01

    Compilation, evaluation and dissemination are essential pieces of work for the nuclear data activities. We, Japan charged particle data group, have researched the utility framework for the nuclear reaction data on the basis of recent progress of computer and network technologies. These technologies will be not only for the data dissemination but for the compilation and evaluation assistance among the many corresponding researchers of all over the world. In this paper, current progress of our research and development is shown. (author)

  4. 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.

  5. Nuclear structure near the particle drip-lines and explosive nucleosynthesis processes

    International Nuclear Information System (INIS)

    Kratz, K.L.; Pfeiffer, B.; Moeller, P.; Thielemann, F.K.; Wiescher, M.

    1999-01-01

    In this paper, we discuss the nuclear physics input for a selected set of explosive nucleosynthesis scenarios leading to rapid proton-- and neutron--capture processes. Observables (like e.g. luminosity curves or elemental abundance distributions) witness the interplay between nuclear structure aspects near the particle drip-lines and the appropriate astrophysical environments, and can give guidance to and constraints on stellar conditions and the associated nucleosynthesis. (authors)

  6. Some recent developments in nuclear charged particle detectors

    International Nuclear Information System (INIS)

    Stelzer, H.

    1980-08-01

    The latest developments of large-area, position sensitive gas-filled ionization chambers are described. Multi-wire-proportional chambers as position-sensing and parallel-plate-avalanche counters as time-sensing detectors at low pressure (5 torr) have proven to be useful and reliable instruments in heavy ion physics. Gas (proportional) scintillation counters, used mainly for x-ray spectroscopy, have recently been applied as particle detectors. Finally, a brief description of a large plastic scintillator spectrometer, the Plastic Ball, is given and some of the first test and calibration data are shown

  7. Atomic and nuclear physics with stored particles in ion traps

    CERN Document Server

    Kluge, H J; Herfurth, F; Quint, W

    2002-01-01

    Trapping and cooling techniques play an increasingly important role in many areas of science. This review concentrates on recent applications of ion traps installed at accelerator facilities to atomic and nuclear physics such as mass spectrometry of radioactive isotopes, weak interaction studies, symmetry tests, determination of fundamental constants, laser spectroscopy, and spectroscopy of highly-charged ions. In addition, ion traps are proven to be extremely efficient devices for (radioactive) ion beam manipulation as, for example, retardation, accumulation, cooling, beam cleaning, charge-breeding, and bunching.

  8. Scaling of charged particle multiplicity distributions in relativistic nuclear collisions

    International Nuclear Information System (INIS)

    Ahamd, N.; Hushnud; Azmi, M.D.; Zafar, M.; Irfan, M.; Khan, M.M.; Tufail, A.

    2011-01-01

    Validity of KNO scaling in hadron-hadron and hadron-nucleus collisions has been tested by several workers. Multiplicity distributions for p-emulsion interactions are found to be consistent with the KNO scaling hypothesis for pp collisions. The applicability of the scaling law was extended to FNAL energies by earlier workers. Slattery has shown that KNO scaling hypothesis is in fine agreement with the data for pp interactions over a wide range of incident energies. An attempt, is, therefore, made to examine the scaling hypothesis using multiplicity distributions of particles produced in 3.7A GeV/c 16 O-, 4.5A GeV/c and 14.5A GeV/c 28 Si - nucleus interactions

  9. From pair correlations to the quasi-particle-phonon nuclear model

    International Nuclear Information System (INIS)

    Solov'ev, V.G.

    1986-01-01

    Modern state of the nucleus theory is discussed. The main attention is paid to pair correlation theory of superconducting type and quasiparticle - phonon nucleus model. Pair correlation account allowed one to describe in detail a series of nucleus properties which did not fall within the framework of earlier known models as, for example, double-quasi-particle states in even-even deformed nuclei. To describe the wave function low-quasi-particle components at low, mean and high excitation energies, the nucleus quasi-particle-phonon model is formulated. The strength function method is used in the model and fragmentation of mono-quasi-particle, mono-phonon states and quasi-particle phonon state by many nuclear levels is calculated

  10. Functional integrals for nuclear many-particle systems

    International Nuclear Information System (INIS)

    Lobanov, Yu.Yu.

    1996-04-01

    The new method for computation of the physical characteristics of quantum systems with many degrees of freedom is described. This method is based on the representation of the matrix element of the evolution operator in Euclidean metrics in a form of the functional integral with a certain measure in the corresponding space and on the use of approximation formulas which we constructed for this kind of integrals. The method does not require preliminary discretization of space and time and allows to use the deterministic algorithms. This approach proved to have important advantages over the other known methods, including the higher efficiency of computations. Examples of application of the method to the numerical study of some potential nuclear models as well as comparison of results with the experimental data and with the values obtained by the other authors are presented. (author). 25 refs, 1 fig., 2 tabs

  11. Some aspects of the description of relativistic particles in external fields. [Time dependent and time independent potentials

    Energy Technology Data Exchange (ETDEWEB)

    Labonte, G

    1973-01-01

    We study the time description of the motion of relativistic particles in both the dependent and time independent potentials. The differential equations of motion considered are the standard linear spin zero and one half equations. They are always meaningful in the sense that, at all times, unique well defined operator valued distributions in the three space variables are determined. We discuss the problem of determining which set of creation and annihilation operators is relevant in a given problem. We examine the implementation of certain simple requirements which seem to be necessary in order for the mathematical formalism to be able to describe a physical system. We show that whenever the equation of motion is homogeneous, the study of all physical requirements reduces to studying Bogoliubov transformations between creation and annihilation operators. We study such transformations where we obtain some new important results concerning their general properties. We examine in detail a quantized field in presence of an external source, electrons and positrons acted upon by a plane electromagnetic wave, Dirac fields acted upon by potentials of the form A(x) delta (t) and A(x) THETA (t-t/sub 0/). We study Dirac fields in presence of potentials which have time dependences which can be represented by sequences of step functions. We then discuss the limiting case where the time dependence is continuous. We prove that the requirements that there exists a unitary evolution operator or that physical particles can be described are exactly equivalent. (auth)

  12. Characterization study of cesium concentrated particles in the soils near the Fukushima Daiichi nuclear power plant

    Science.gov (United States)

    Satou, Yukihiko; Sueki, Keisuke; Sasa, Kimikazu; Adachi, Kouji; Igarashi, Yasuhito

    2015-04-01

    Radionuclides from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident contaminated a vast area. Two types of contamination, spread and spot types, were observed in soils with autoradiography using an imaging plate. Other samples such as dust filters, vegetation, X-ray films, and so on, also indicate the spot type contamination in the early stage of the FDNPP accident. The source of spot type contamination is well known as hot particles at the Chernobyl Nuclear Power Plant (ChNPP) accident in 1986. Hot particles were divided into two groups, fuel hot particles and fission product particles, and they were emitted directly from reactor core with phreatic explosion and fire. In contrast, the official reports of the FDNPP accident did not conforme core explosion. In addition, the emitted total amount of Uranium was very few (Yamamoto et al., 2014). Thus, the spot type contaminations were not identified as the same of hot particles yet. Therefore, the present study aimed to pick up and identify the spot contaminations in soils. Surface soil samples were collected at 20 km northwest from the FDNPP in June 2013. Soils were spread in plastic bags for autoradiography with imaging plate analysis. Then, the soil particles were collected on a sticky carbon tape and analyzed by SEM-EDS to detect radioactive particles. Finally, particles were confirmed to contain photo peaks in the γ-spectrum by a germanium semiconductor detector. Four radioactive particles were isolated from the soil samples in the present study. Detected γ-ray emission radionuclides were only Cs-134 and Cs-137. The X-ray spectra on the SEM-EDS of all particles showed a Cs peak as well as O, Fe, Zn, and Rb peaks, and these elements were distributed uniformly within the particles. In addition, uniform distribution of Si was also shown. Moreover, U was detected from one of the particles, but U concentration was very low and existed locally in the particle. These characters are very similar to previous

  13. Calibrations of CR39 and Makrofol nuclear track detectors and search for exotic particles

    CERN Document Server

    Ambrosio, M; Auriemma, G; Bakari, D; Baldini, A; Barbarino, G C; Barish, B C; Battistoni, G; Becherini, Y; Bellotti, R; Bemporad, C; Bernardini, P; Bilokon, H; Bloise, C; Bower, C; Brigida, M; Bussino, S; Cafagna, F; Calicchio, M; Campana, D; Carboni, M; Caruso, R; Cecchini, S; Cei, F; Chiarella, V; Chiarusi, T; Choudhary, B C; Coutu, S; Cozzi, M; De Cataldo, G; De Marzo, C; De Mitri, I; De Vincenzi, M; Dekhissi, H; Derkaoui, J; Di Credico, A; Erriquez, O; Favuzzi, C; Forti, C; Fusco, P; Giacomelli, G; Giannini, G; Giglietto, N; Giorgini, M; Grassi, M; Grillo, A; Guarino, F; Gustavino, C; Habig, A; Hanson, K; Heinz, R; Iarocci, E; Katsavounidis, E; Katsavounidis, I; Kearns, E; Kim, H; Kumar, A; Kyriazopoulou, S; Lamanna, E; Lane, C; Levin, D S; Lipari, P; Longley, N P; Longo, M J; Loparco, F; Maaroufi, F; Mancarella, G; Mandrioli, G; Manzoor, S; Margiotta, A; Marini, A; Martello, D; Marzari-Chiesa, A; Matteuzzi, D; Mazziotta, M N; Michael, D G; Monacelli, P; Montaruli, T; Monteno, M; Mufson, S; Musser, J; Nicolò, D; Nolty, R; Orth, C; Osteria, G; Palamara, O; Patera, V; Patrizii, L; Pazzi, R; Peck, C W; Perrone, L; Petrera, S; Pistilli, P; Popa, V; Rainó, A; Reynoldson, J; Ronga, F; Rrhioua, A; Satriano, C; Scapparone, E; Scholberg, K; Sciubba, A; Serra, P; Sioli, M; Sirri, G; Sitta, M; Spinelli, P; Spinetti, M; Spurio, M; Steinberg, R; Stone, J L; Sulak, L R; Surdo, A; Tarle, G; Togo, V; Vakili, M; Walter, C W; Webb, R; 10.1016/S0920-5632(03)02249-7

    2003-01-01

    We present the final results of the search for exotic massive particles in the cosmic radiation performed with the MACRO underground experiment. Magnetic monopoles and nuclearites flux upper limits obtained with the CR39 nuclear track subdetector, the scintillation and streamer tube subdetectors are given. Searches at high altitude with the SLIM experiment are in progress.

  14. NRABASE 2.0. Charged-particle nuclear reaction data for ion beam analysis

    International Nuclear Information System (INIS)

    Gurbich, A.F.

    1997-01-01

    For 30 targets between H-1 and Ag-109, differential cross sections for reactions induced by protons, deuterons, He-3 and alpha particles are given in tabular and graphical form. The data were compiled from original experimental references. The database was developed under a research contract with the IAEA Physics Section and is available on diskette from the IAEA Nuclear Data Section. (author)

  15. Reactions of charged and neutral recoil particles following nuclear transformations. Final report

    International Nuclear Information System (INIS)

    Ache, H.J.

    1980-12-01

    A summary is given of the various activities conducted as part of the research on the chemical reactions of energetic particles generated in nuclear reactions. Emphasis was on hot atom chemistry in gases and liquids. A bibliography of 110 publications published as part of the program is included

  16. Single Particle Potential of a Σ Hyperon in Nuclear Matter. II Rearrangement Effects

    International Nuclear Information System (INIS)

    Dabrowski, J.

    2000-01-01

    The rearrangement contribution to the real part of the single particle potential of a Σ hyperon in nuclear matter, U Σ , is investigated. The isospin and spin dependent parts of U Σ are considered. Results obtained for four models of the Nijmegen baryon-baryon interaction are presented and discussed. (author)

  17. The maximum entropy determination of nuclear densities of calcium isotopes from elastic scattering of alpha particles

    International Nuclear Information System (INIS)

    Engel, Y.M.; Friedman, E.; Levine, R.D.

    1982-01-01

    Radial moments of the real part of the optical potential for elastic scattering of 104 MeV α particles are used as constraints, in determining the nuclear density of maximal entropy. The potential is related to the density by the folding model. (orig.)

  18. A nuclear field treatment of the 3-particle system outside closed-shell nuclei

    International Nuclear Information System (INIS)

    Liotta, R.J.; Silvestre-Brac, B.

    1978-01-01

    The nuclear field treatment of the 3-particle system is carried out to all orders of perturbation theory but without including hole-excitations. It is shown that the theory properly corrects both the Pauli principle violations and the overcompleteness of the basis

  19. Time scales for spinodal decomposition in nuclear matter with pseudo-particle model

    Energy Technology Data Exchange (ETDEWEB)

    Idier, D.; Benhassine, B.; Farine, M.; Remaud, B.; Sebille, F.

    1993-12-31

    Dynamical instabilities arising from fluctuations in the spinodal zone for nuclear matter are studied using a large variety of zero range interactions in the frame of a pseudo-particle model. Scale times for spinodal decomposition are extracted and a possible link with decomposition in real heavy-ion collisions is discussed. (author) 12 refs.; 6 figs.; 1 tab.

  20. Time scales for spinodal decomposition in nuclear matter with pseudo-particle model

    International Nuclear Information System (INIS)

    Idier, D.; Benhassine, B.; Farine, M.; Remaud, B.; Sebille, F.

    1993-01-01

    Dynamical instabilities arising from fluctuations in the spinodal zone for nuclear matter are studied using a large variety of zero range interactions in the frame of a pseudo-particle model. Scale times for spinodal decomposition are extracted and a possible link with decomposition in real heavy-ion collisions is discussed. (author) 12 refs.; 6 figs.; 1 tab

  1. Two- and three-particle interference correlations of identical bosons and fermions with close momenta in the model of independent point-like sources

    International Nuclear Information System (INIS)

    Lyuboshits, V.L.

    1991-01-01

    Interference correlations introduced between identical particles with close momenta by the effect of Bose or Fermi statistics are discussed. Relations describing two- and three-particle correlations of identical bosons and fermions with arbitrary spin and arbitrary spin polarization are obtained on the basis of the model of independent single-particle point-like sources. The general structure of the dependence of narrow two- and three-particle correlations on the difference of the four-momenta in the presence of several groups of single-particle sources with different space-time distributions is analyzed. The idea of many-particle point sources of identical bosons is introduced. The suppression of two- and three-particle interference correlations between identical π mesons under conditions when one or several many-particle sources are added to a system of randomly distributed independent single-particle sources is studied. It is shown that if the multiplicities of the particles emitted by the sources are distributed according to the Poisson law, the present results agree with the relations obtained by means of the formalism of coherent states. This agreement also holds in the limit of very large multiplicities with any distribution laws

  2. Gordon Conference on Nuclear Research

    International Nuclear Information System (INIS)

    Austin, S.M.

    1983-09-01

    Session topics were: quarks and nuclear physics; anomalons and anti-protons; the independent particle structure of nuclei; relativistic descriptions of nuclear structure and scattering; nuclear structure at high excitation; advances in nuclear astrophysics; properties of nuclear material; the earliest moments of the universe; and pions and spin excitations in nuclei

  3. Nuclear microprobe analysis and source apportionment of individual atmospheric aerosol particles

    International Nuclear Information System (INIS)

    Artaxo, P.; Rabello, M.L.C.; Watt, F.; Grime, G.; Swietlicki, E.

    1993-01-01

    In atmospheric aerosol reserach, one key issue is to determine the sources of the airborne particles. Bulk PIXE analysis coupled with receptor modeling provides a useful, but limited view of the aerosol sources influencing one particular site or sample. The scanning nuclear microprobe (SNM) technique is a microanalytical technique that gives unique information on individual aerosol particles. In the SNM analyses a 1.0 μm size 2.4 MeV proton beam from the Oxford SNM was used. The trace elements with Z>11 were measured by the particle induced X-ray emission (PIXE) method with detection limits in the 1-10 ppm range. Carbon, nitrogen and oxygen are measured simultaneously using Rutherford backscattering spectrometry (RBS). Atmospheric aerosol particles were collected at the Brazilian Antarctic Station and at biomass burning sites in the Amazon basin tropical rain forest in Brazil. In the Antarctic samples, the sea-salt aerosol particles were clearly predominating, with NaCl and CaSO 4 as major compounds with several trace elements as Al, Si, P, K, Mn, Fe, Ni, Cu, Zn, Br, Sr, and Pb. Factor analysis of the elemental data showed the presence of four components: 1) Soil dust particles; 2) NaCl particles; 3) CaSO 4 with Sr; and 4) Br and Mg. Strontium, observed at 20-100 ppm levels, was always present in the CaSO 4 particles. The hierarchical cluster procedure gave results similar to the ones obtained through factor analysis. For the tropical rain forest biomass burning aerosol emissions, biogenic particles with a high organic content dominate the particle population, while K, P, Ca, Mg, Zn, and Si are the dominant elements. Zinc at 10-200 ppm is present in biogenic particles rich in P and K. The quantitative aspects and excellent detection limits make SNM analysis of individual aerosol particles a very powerful analytical tool. (orig.)

  4. Estimation of the sizes of hot nuclear systems from particle-particle large angle kinematical correlations

    International Nuclear Information System (INIS)

    La Ville, J.L.; Bizard, G.; Durand, D.; Jin, G.M.; Rosato, E.

    1990-06-01

    Light fragment emission, when triggered by large transverse momentum protons shows specific kinematical correlations due to recoil effects of the excited emitting source. Such effects have been observed in azimuthal angular distributions of He-particles produced in collisions induced by 94 MeV/u 16 0 ions on Al, Ni and Au targets. A model calculation assuming a two-stage mechanism (formation and sequential decay of a hot source) gives a good description of these whole data. From this succesfull confrontation, it is possible to estimate the size of the emitting system

  5. An independent safety assessment of Department of Energy nuclear reactor facilities: Safety overview and management function

    International Nuclear Information System (INIS)

    Booth, M.; Brodsky, R.S.; Frankhouser, W.L.

    1981-02-01

    The Under Secretary of Energy established the Nuclear Facilities Personnel Qualification and Training (NFPQT) Committee in October, 1979, in the aftermath of the Three Mile Island (TMI) nuclear accident, to assess the adequacy of training of personnel at DOE nuclear facilities. Subsequently, in February, 1980, the charge to this Committee was modified to assess all implications of the Kemeny Commission report on TMI with regard to DOE nuclear reactors, excluding those in the Division of Naval Reactors. The modified charge was also limited, for the time being, to reactor facilities instead of all nuclear facilities. This report describes the portion of the revised assessment activities that was assigned to the Assessment Support Team

  6. Identification of nuclear power plant transients using the Particle Swarm Optimization algorithm

    International Nuclear Information System (INIS)

    Canedo Medeiros, Jose Antonio Carlos; Schirru, Roberto

    2008-01-01

    In order to help nuclear power plant operator reduce his cognitive load and increase his available time to maintain the plant operating in a safe condition, transient identification systems have been devised to help operators identify possible plant transients and take fast and right corrective actions in due time. In the design of classification systems for identification of nuclear power plants transients, several artificial intelligence techniques, involving expert systems, neuro-fuzzy and genetic algorithms have been used. In this work we explore the ability of the Particle Swarm Optimization algorithm (PSO) as a tool for optimizing a distance-based discrimination transient classification method, giving also an innovative solution for searching the best set of prototypes for identification of transients. The Particle Swarm Optimization algorithm was successfully applied to the optimization of a nuclear power plant transient identification problem. Comparing the PSO to similar methods found in literature it has shown better results

  7. Identification of nuclear power plant transients using the Particle Swarm Optimization algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Canedo Medeiros, Jose Antonio Carlos [Universidade Federal do Rio de Janeiro, PEN/COPPE, UFRJ, Ilha do Fundao s/n, CEP 21945-970 Rio de Janeiro (Brazil)], E-mail: canedo@lmp.ufrj.br; Schirru, Roberto [Universidade Federal do Rio de Janeiro, PEN/COPPE, UFRJ, Ilha do Fundao s/n, CEP 21945-970 Rio de Janeiro (Brazil)], E-mail: schirru@lmp.ufrj.br

    2008-04-15

    In order to help nuclear power plant operator reduce his cognitive load and increase his available time to maintain the plant operating in a safe condition, transient identification systems have been devised to help operators identify possible plant transients and take fast and right corrective actions in due time. In the design of classification systems for identification of nuclear power plants transients, several artificial intelligence techniques, involving expert systems, neuro-fuzzy and genetic algorithms have been used. In this work we explore the ability of the Particle Swarm Optimization algorithm (PSO) as a tool for optimizing a distance-based discrimination transient classification method, giving also an innovative solution for searching the best set of prototypes for identification of transients. The Particle Swarm Optimization algorithm was successfully applied to the optimization of a nuclear power plant transient identification problem. Comparing the PSO to similar methods found in literature it has shown better results.

  8. Investigation of the production of slow particles in 60 A GeV 16O induced nuclear emulsion reaction

    International Nuclear Information System (INIS)

    Zhang Donghai

    2001-01-01

    The multiplicity distributions and correlations of grey track producing particles (N g ), black track producing particles (N b ) and heavy track producing particles (N h ) have been studied in 60 A GeV 16 O induced nuclear emulsion reaction. The multiplicity distributions of grey particles, black particles and heavy track producing particles can be reproduced by FRITIOF (version 1.7) taking cascade mechanism in to account and DTUNUC2.0 with an incident energy of 200 A GeV. The mean multiplicity of black particles (N b ) increases with the number of grey particle N g up to 10 and then exhibits a saturation for peripheral, central and mini-bias events; the average values of grey particles g > (heavy track producing particles h > increase with increasing values of black particle N b (grey particle N g )

  9. Removal of toxic uranium from synthetic nuclear power reactor effluents using uranyl ion imprinted polymer particles.

    Science.gov (United States)

    Preetha, Chandrika Ravindran; Gladis, Joseph Mary; Rao, Talasila Prasada; Venkateswaran, Gopala

    2006-05-01

    Major quantities of uranium find use as nuclear fuel in nuclear power reactors. In view of the extreme toxicity of uranium and consequent stringent limits fixed by WHO and various national governments, it is essential to remove uranium from nuclear power reactor effluents before discharge into environment. Ion imprinted polymer (IIP) materials have traditionally been used for the recovery of uranium from dilute aqueous solutions prior to detection or from seawater. We now describe the use of IIP materials for selective removal of uranium from a typical synthetic nuclear power reactor effluent. The IIP materials were prepared for uranyl ion (imprint ion) by forming binary salicylaldoxime (SALO) or 4-vinylpyridine (VP) or ternary SALO-VP complexes in 2-methoxyethanol (porogen) and copolymerizing in the presence of styrene (monomer), divinylbenzene (cross-linking monomer), and 2,2'-azobisisobutyronitrile (initiator). The resulting materials were then ground and sieved to obtain unleached polymer particles. Leached IIP particles were obtained by leaching the imprint ions with 6.0 M HCl. Control polymer particles were also prepared analogously without the imprint ion. The IIP particles obtained with ternary complex alone gave quantitative removal of uranyl ion in the pH range 3.5-5.0 with as low as 0.08 g. The retention capacity of uranyl IIP particles was found to be 98.50 mg/g of polymer. The present study successfully demonstrates the feasibility of removing uranyl ions selectively in the range 5 microg - 300 mg present in 500 mL of synthetic nuclear power reactor effluent containing a host of other inorganic species.

  10. 1997 report of the scientific evaluation committee of DAPNIA (Department of astrophysics, particle physics, nuclear physics and instrumentation)

    International Nuclear Information System (INIS)

    Anon.

    1998-01-01

    The DAPNIA is a department of CEA, its main characteristic is to manage scientific teams working on astrophysics, nuclear physics, elementary particles and instrumentation. Every 2 years DAPNIA's activities are submitted to an evaluation made by a scientific committee whose members are experts independent from CEA. This committee reviews the work done, gives an opinion about the options chosen for the projects to come and writes out a report. In 1997 the committee had a very positive opinion of the work done by DAPNIA teams. The contributions to various and important national or international programs have been successful, we can quote: Ulysse mission, soho, iso, integral for spatial programs, aleph, delphi, H1 at Hera, atlas, cms, na48, nomad, babar, antares for particle physics and spiral, smc, compass for nuclear physics. The committee advises DAPNIA to favour more contacts between the theoreticians and the experimentalists who work on quantum chromodynamics and hadron physics. The committee shows its concern about improving the balance between the means dedicated to instrumentation designing and those dedicated to the analysis and interpretation of the experimental data collected. (A.C.)

  11. Radiation doping methods of semiconductor materials: the nuclear doping by charged particles

    International Nuclear Information System (INIS)

    Kozlovskii, V.V.; Zakharenkov, L.F.

    1996-01-01

    A review is given of the state of the art in one of the current topics in radiation doping of semiconductors, which is process of nuclear transmutation doping (NTD) by charged particles. In contrast to the neutron and photonuclear transmutation doping, which have been dealt with in monograths and reviews, NTD caused by the action of charged particles is a subject growing very rapidly in the last 10-15 years, but still lacking systematic accounts. The review consists of three sections. The first section deals with the characteristics of nuclear reactions in semiconductors caused by the action of charged particles: the main stress is on the modeling of NTD processes in semiconductors under the action of charged particles. In the second section the state of the art of experimental investigations of NTD under the influence of charged particles is considered. An analysis is made of the communications reporting experimental data on the total numbers of dopants which are introduced, concentration of the electrically active fraction of the impurity, profiles of the dopant distributions, and conditions for efficient annealing of radiation defects. The third section deals with the suitability of NTD by charged particles for the fabrication of semiconductor devices. (author)

  12. 4-D single particle tracking of synthetic and proteinaceous microspheres reveals preferential movement of nuclear particles along chromatin – poor tracks

    Directory of Open Access Journals (Sweden)

    Athale Chaitanya

    2004-11-01

    Full Text Available Abstract Background The dynamics of nuclear organization, nuclear bodies and RNPs in particular has been the focus of many studies. To understand their function, knowledge of their spatial nuclear position and temporal translocation is essential. Typically, such studies generate a wealth of data that require novel methods in image analysis and computational tools to quantitatively track particle movement on the background of moving cells and shape changing nuclei. Results We developed a novel 4-D image processing platform (TIKAL for the work with laser scanning and wide field microscopes. TIKAL provides a registration software for correcting global movements and local deformations of cells as well as 2-D and 3-D tracking software. With this new tool, we studied the dynamics of two different types of nuclear particles, namely nuclear bodies made from GFP-NLS-vimentin and microinjected 0.1 μm – wide polystyrene beads, by live cell time-lapse microscopy combined with single particle tracking and mobility analysis. We now provide a tool for the automatic 3-D analysis of particle movement in parallel with the acquisition of chromatin density data. Conclusions Kinetic analysis revealed 4 modes of movement: confined obstructed, normal diffusion and directed motion. Particle tracking on the background of stained chromatin revealed that particle movement is directly related to local reorganization of chromatin. Further a direct comparison of particle movement in the nucleoplasm and the cytoplasm exhibited an entirely different kinetic behaviour of vimentin particles in both compartments. The kinetics of nuclear particles were slightly affected by depletion of ATP and significantly disturbed by disruption of actin and microtubule networks. Moreover, the hydration state of the nucleus had a strong impact on the mobility of nuclear bodies since both normal diffusion and directed motion were entirely abolished when cells were challenged with 0.6 M

  13. 4-D single particle tracking of synthetic and proteinaceous microspheres reveals preferential movement of nuclear particles along chromatin – poor tracks

    Science.gov (United States)

    Bacher, Christian P; Reichenzeller, Michaela; Athale, Chaitanya; Herrmann, Harald; Eils, Roland

    2004-01-01

    Background The dynamics of nuclear organization, nuclear bodies and RNPs in particular has been the focus of many studies. To understand their function, knowledge of their spatial nuclear position and temporal translocation is essential. Typically, such studies generate a wealth of data that require novel methods in image analysis and computational tools to quantitatively track particle movement on the background of moving cells and shape changing nuclei. Results We developed a novel 4-D image processing platform (TIKAL) for the work with laser scanning and wide field microscopes. TIKAL provides a registration software for correcting global movements and local deformations of cells as well as 2-D and 3-D tracking software. With this new tool, we studied the dynamics of two different types of nuclear particles, namely nuclear bodies made from GFP-NLS-vimentin and microinjected 0.1 μm – wide polystyrene beads, by live cell time-lapse microscopy combined with single particle tracking and mobility analysis. We now provide a tool for the automatic 3-D analysis of particle movement in parallel with the acquisition of chromatin density data. Conclusions Kinetic analysis revealed 4 modes of movement: confined obstructed, normal diffusion and directed motion. Particle tracking on the background of stained chromatin revealed that particle movement is directly related to local reorganization of chromatin. Further a direct comparison of particle movement in the nucleoplasm and the cytoplasm exhibited an entirely different kinetic behaviour of vimentin particles in both compartments. The kinetics of nuclear particles were slightly affected by depletion of ATP and significantly disturbed by disruption of actin and microtubule networks. Moreover, the hydration state of the nucleus had a strong impact on the mobility of nuclear bodies since both normal diffusion and directed motion were entirely abolished when cells were challenged with 0.6 M sorbitol. This effect correlated

  14. Australia and the nuclear choice - the report of the independent committee of inquiry into the nuclear weapons and other consequences of Australian uranium mining

    International Nuclear Information System (INIS)

    Anon.

    1984-06-01

    Results are presented of an independent inquiry which was run simultaneously with the Australian Science and Technology Council's inquiry into Australia's role in the nuclear fuel cycle. The inquiry's chairperson was Dr. Keith Suter. The report explores the link between nuclear power and nuclear weapons proliferation. It examines Australia's role as a supplier of uranium and considers such areas as problems of the fuel cycle including environmental, occupational and waste disposal hazards and the political economy of nuclear energy as well as the problem of nuclear weapons proliferation. Twenty one recommendations are made in the areas of proliferation; safeguards; alternatives to nuclear power; reorganization of the I.A.E.A. to form a separate regulatory agency; contracts to supply uranium; prohibition of enrichment facilities, storage of foreign waste and nuclear power stations within Australia; nuclear weapons and waste free zones; and radioactive waste disposal. The logic of the report and the recommendations would suggest immediate cessation of uranium supply, however the Committee recognised the legal necessity to meet existing contracts. Sixty submissions were received

  15. Aerosol particle transport modeling for preclosure safety studies of nuclear waste repositories

    International Nuclear Information System (INIS)

    Gelbard, F.

    1989-01-01

    An important concern for preclosure safety analysis of a nuclear waste repository is the potential release to the environment of respirable aerosol particles. Such particles, less than 10 μm in aerodynamic diameter, may have significant adverse health effects if inhaled. To assess the potential health effects of these particles, it is not sufficient to determine the mass fraction of respirable aerosol. The chemical composition of the particles is also of importance since different radionuclides may pose vastly different health hazards. Thus, models are needed to determine under normal and accident conditions the particle size and the chemical composition distributions of aerosol particles as a function of time and of position in the repository. In this work a multicomponent sectional aerosol model is used to determine the aerosol particle size and composition distributions in the repository. A range of aerosol mass releases with varying mean particle sizes and chemical compositions is used to demonstrate the sensitivities and uncertainties of the model. Decontamination factors for some locations in the repository are presented. 8 refs., 1 tab

  16. Public's right to information: An independent safety assessment of Department of Energy nuclear reactor facilities

    International Nuclear Information System (INIS)

    Stokely, E.

    1981-02-01

    The events at TMI prompted the Under Secretary of the Department of Energy (DOE) to establish the Nuclear Facilities Personnel Qualification and Training (NFPQT) Committee. This Committee was assigned the task of assessing the adequacy of nuclear facility personnel qualification and training at DOE-owned reactors in light of the Three Mile Island accident. The Committee was also asked to review recommendations and identify possible implications for DOE's nuclear facilities

  17. 1-3 Nuclear In-medium Effects of Strange Particles in Proton-nucleus Collisions

    Institute of Scientific and Technical Information of China (English)

    Feng; Zhaoqing[1

    2014-01-01

    Extraction of the in-medium properties of strange particles from heavy-ion collisions is very complicated, since he nuclear density varies in the evolution of nucleus-nucleus collisions. To avoid the uncertainties of the baryon ensities during the stage of strange particle production, one can investigate proton-nucleus collisions where the uclear density is definite around the saturation density. Dynamics of strange particles produced in the protoninduced uclear the reactions near the threshold energies has been investigated within the Lanzhou quantum olecular dynamics (LQMD) transport model. The in-medium modifications on particle production in densenuclear matter are considered through the corrections to the elementary cross sections via the effective mass and he mean-field potentials[1].

  18. Reconstruction of the size of nuclear fuel particle aerosol by the investigation of a radionuclide behaviour in body of the Chernobyl accident witnesses

    International Nuclear Information System (INIS)

    Kutkov, V.A.

    1996-01-01

    As a result of the Chernobyl NPP (ChNPP) accident aerosol particles of dispersed nuclear fuel were released to the atmosphere. Inhalation of those aerosol became the source of internal exposure for witnesses of the Chernobyl accident. To assess correctly internal doses from a mixture of radionuclides present in air in the form of aerosol particles one mast assign each radionuclide to a certain inhalation class by its chemical speciation in aerosol and define the airborne characteristics (the activity median aerodynamic diameter, AMAD and the standard geometric deviation, fig) of that particular aerosol. Moreover, information on any particular radionuclide is useless for other components since, in such a mixture, the radionuclides are generally independent and may belong to different particles. On the contrary, all nuclear fuel particle (NFP) radionuclides belong to the same particle, being matrix-bound. The collective behaviour of the matrix-bound radionuclides in the environment and in the human barrier organs makes it possible to spread to the aerosol of NFP any estimates of AMAD and β g obtained for any particular NFP radionuclide. This is principal feature of NFP aerosol as distinguished from a mere mixture of aerosol particles carry different radionuclides. (author)

  19. Alpha-particle dosimetry using solid state nuclear track detectors. Application to 222Rn and its daughters

    International Nuclear Information System (INIS)

    Barillon, R.; Chambaudet, A.

    2000-01-01

    A methodology for the determination of the detection efficiency of a solid state nuclear track detector for radon and its short-lived daughters was presented. First, particular attention is paid to the α-particles having energies and angles of incidence that lead to observable tracks after an adapted chemical etching. The results are then incorporated in a mathematical model to determine the theoretical radon detection efficiency of a polymeric detector placed in a cylindrical cell. When applied to LR115 and CR39 detectors, the model reveals the influence of the position of the radon daughters inside the cell. Radon daughters tend to link up with natural atmospheric aerosols and then settle on the cell's inside wall. This model allows to determine, among other things, the cell size for which the detector response is independent of the fraction daughters plated out. (author)

  20. Verification of nuclear data for DT neutron induced charged-particle emission reaction of light nuclei

    International Nuclear Information System (INIS)

    Kondo, K.; Murata, I.; Ochiai, K.; Kubota, N.; Miyamaru, H.; Takagi, S.; Shido, S.; Konno, C.; Nishitani, T.

    2007-01-01

    Double-differential cross-section (DDX) for emitted charged particles is necessary to estimate material damage, gas production and nuclear heating in a fusion reactor. Detailed measurements of the cross-sections for beryllium, carbon and fluorine, which are among the composition materials of expected fusion blankets and first walls, were carried out with a charged-particle spectrometer using a pencil-beam DT neutron source. As verification of the cross-sections evaluated in three nuclear libraries (JENDL-3.3, ENDF/B-VI and JEFF-3.1), our measured data were compared with the data evaluated in the libraries. From the comparison, the following problems were pointed out: Beryllium: Remarkable differences in energy and angular distribution for α-particles were observed between the measured data and the libraries. The estimated total cross-section for α-particle production well agreed with the libraries. Carbon: There was a discrepancy of about 20% between JENDL-3.3 and ENDF/B-VI (JEFF-3.1) for α-particle production cross-section, and no DDX for α-particles is given in the libraries. Our obtained total cross-section for α-particle production was rather consistent with ENDF/B-VI (JEFF-3.1), and the value evaluated in JENDL-3.3 seemed too large. Fluorine: The remarkable differences for DDX of protons and α-particles were observed between the obtained result and JENDL-3.3, although detailed DDX was stored only in JENDL. The obtained total cross-sections mostly supported the evaluation of ENDF/B-VI (JEFF-3.1)

  1. A novel chromosome region maintenance 1-independent nuclear export signal of the large form of hepatitis delta antigen that is required for the viral assembly.

    Science.gov (United States)

    Lee, C H; Chang, S C; Wu, C H; Chang, M F

    2001-03-16

    Hepatitis delta virus (HDV) is a satellite virus of hepatitis B virus, as it requires hepatitis B virus for virion production and transmission. We have previously demonstrated that sequences within the C-terminal 19-amino acid domain flanking the isoprenylation motif of the large hepatitis delta antigen (HDAg-L) are important for virion assembly. In this study, site-directed mutagenesis and immunofluorescence staining demonstrated that in the absence of hepatitis B virus surface antigen (HBsAg), the wild-type HDAg-L was localized in the nuclei of transfected COS7 cells. Nevertheless, in the presence of HBsAg, the HDAg-L became both nuclei- and cytoplasm-distributed in about half of the cells. An HDAg-L mutant with a substitution of Pro-205 to alanine could neither form HDV-like particles nor shift the subcellular localization in the presence of HBsAg. In addition, nuclear trafficking of HDAg-L in heterokaryons indicated that HDAg-L is a nucleocytoplasmic shuttling protein. A proline-rich HDAg peptide spanning amino acid residues 198 to 210, designated NES(HDAg-L), can function as a nuclear export signal (NES) in Xenopus oocytes. Pro-205 is critical for the NES function. Furthermore, assembly of HDV is insensitive to leptomycin B, indicating that the NES(HDAg-L) directs nuclear export of HDAg-L to the cytoplasm via a chromosome region maintenance 1-independent pathway.

  2. Proceedings of the nuclear and particle physics on the light cone workshop

    International Nuclear Information System (INIS)

    Johnson, M.B.; Kisslinger, L.

    1988-01-01

    This book deals with phenomena in nuclear and particle physics that occur at high energy and at high momentum transfer. At high energy, particles move near the light cone, and the topics covered deal with the physics from this perspective. The light-cone description is familiar in particle physics, but until recently it has not been used in nuclear physics. In view of the fact that nuclear physicists are increasingly looking to questions that can be answered only by experiments in the range of energy where the light-cone description seems to be of advantage, and that the ideas involved are new to many people in the nuclear physics community, efforts were made to ensure that each main speaker would give an introduction to the subject as well as present recent developments. The book should, therefore, be valuable to those who want to learn about light-cone approaches, in particular experimentalists and students, as well as to specialists. The volume is divided into eight chapters. The first chapter is an overview of the meeting and an introduction to the subject of light-cone physics. The remaining chapters encompass various applications and current topics in nuclear and particle physics where use of light-cone methods leads to understanding of high-energy phenomena and their connection to the quark and mesonic substructure of the nucleus. These include the main talks containing the introductory material, as well as shorter papers on the more specialized topics of current interest in both experimental and theoretical aspects of the subject. 38 papers have been cataloged separately

  3. Charge independence and charge symmetry

    Energy Technology Data Exchange (ETDEWEB)

    Miller, G A [Washington Univ., Seattle, WA (United States). Dept. of Physics; van Oers, W T.H. [Manitoba Univ., Winnipeg, MB (Canada). Dept. of Physics; [TRIUMF, Vancouver, BC (Canada)

    1994-09-01

    Charge independence and charge symmetry are approximate symmetries of nature, violated by the perturbing effects of the mass difference between up and down quarks and by electromagnetic interactions. The observations of the symmetry breaking effects in nuclear and particle physics and the implications of those effects are reviewed. (author). 145 refs., 3 tabs., 11 figs.

  4. Charge independence and charge symmetry

    International Nuclear Information System (INIS)

    Miller, G.A.

    1994-09-01

    Charge independence and charge symmetry are approximate symmetries of nature, violated by the perturbing effects of the mass difference between up and down quarks and by electromagnetic interactions. The observations of the symmetry breaking effects in nuclear and particle physics and the implications of those effects are reviewed. (author). 145 refs., 3 tabs., 11 figs

  5. Particle accelerator

    International Nuclear Information System (INIS)

    Ress, R.I.

    1976-01-01

    Charged particles are entrained in a predetermined direction, independent of their polarity, in a circular orbit by a magnetic field rotating at high speed about an axis in a closed cylindrical or toroidal vessel. The field may be generated by a cylindrical laser structure, whose beam is polygonally reflected from the walls of an excited cavity centered on the axis, or by high-frequency energization of a set of electromagnets perpendicular to the axis. In the latter case, a separate magnetostatic axial field limits the orbital radius of the particles. These rotating and stationary magnetic fields may be generated centrally or by individual magnets peripherally spaced along its circular orbit. Chemical or nuclear reactions can be induced by collisions between the orbiting particles and an injected reactant, or by diverting high-speed particles from one doughnut into the path of counterrotating particles in an adjoining doughnut

  6. Design of particle bed reactors for the space nuclear thermal propulsion program

    International Nuclear Information System (INIS)

    Ludewig, H.; Powell, J.R.; Todosow, M.; Maise, G.; Barletta, R.; Schweitzer, D.G.

    1996-01-01

    This paper describes the design for the Particle Bed Reactor (PBR) that was considered for the Space Nuclear Thermal Propulsion (SNTP) Program. The methods of analysis and their validation are outlined first. Monte Carlo methods were used for the physics analysis, several new algorithms were developed for the fluid dynamics, heat transfer and transient analysis; and commercial codes were used for the stress analysis. We carried out a critical experiment, prototypic of the PBR to validate the reactor physics; blowdown experiments with beds of prototypic dimensions were undertaken to validate the power-extraction capabilities from particle beds. In addition, materials and mechanical design concepts for the fuel elements were experimentally validated. (author)

  7. Dark-field scanning confocal microscope for vertical particle tracks in nuclear emulsion

    International Nuclear Information System (INIS)

    Astakhov, A.Ya.; Batusov, Yu.A.; Soroko, L.M.; Tereshchenko, S.V.; Tereshchenko, V.V.

    1999-01-01

    The principle of the DArk-FIeld Scanning CONfocal (DAFISCON) microscope for selective observation of the vertical particle tracks in nuclear emulsion is described. The construction of the DAFISCON microscope, built on the basis of the 2D measurement microscope, is described. The results of the experimental testing of the DAFISCON microscope, accomplished at high density of the vertical particle tracks, are presented. The 2D plot and the 1D plot of the CCD dark-field image are given. The spatial resolution of our microscope can be increased by using the objective with higher aperture

  8. Development of charged particle nuclear reaction data retrieval system on IntelligentPad

    International Nuclear Information System (INIS)

    Ohbayashi, Yosihide; Masui, Hiroshi; Aoyama, Shigeyoshi; Kato, Kiyoshi; Chiba, Masaki

    1999-01-01

    An newly designed database retrieval system of charged particle nuclear reaction database system is developed with IntelligentPad architecture. We designed the network-based (server-client) data retrieval system, and a client system constructs on Windows95, 98/NT with IntelligentPad. We set the future aim of our database system toward the 'effective' use of nuclear reaction data: I. 'Re-produce, Re-edit, Re-use', II. 'Circulation, Evolution', III. 'Knowledge discovery'. Thus, further developments are under way. (author)

  9. Nuclear matter with a pseudo-particle model: static bulk and surface properties

    International Nuclear Information System (INIS)

    Idier, D.; Benhassine, B.; Farine, M.; Remaud, B.; Sebille, F.

    1993-01-01

    Direct calculations of cold and hot nuclear matter (bulk and surface properties) are carried out within the frame of a pseudo-particle model using a gaussian decomposition of the distribution function. Comparisons with Hartree-Fock calculations, for a large class of effective interactions, show that such a model is reliable to reproduce accurately the equation of state of nuclear matter for large ranges of densities and temperatures. The number of gaussians per nucleon and the gaussian widths are critical parameters in that semi-classical model. (orig.)

  10. Nuclear matter with pseudo-particle model: static bulk and surface properties

    Energy Technology Data Exchange (ETDEWEB)

    Idier, D.; Benhassine, B.; Farine, M.; Remaud, B.; Sebille, F.

    1993-12-31

    Direct calculations of cold and hot nuclear matter (bulk and surface properties) are carried out within the frame of a pseudo-particle model using a Gaussian decomposition of the distribution function. Comparisons with Hartree-Fock calculations, for a large class of effective interactions, show that such a model is reliable to reproduce accurately the equation of state of nuclear matter for large ranges of densities and temperatures. The number of Gaussian per nucleon and the Gaussian widths are critical parameters in that semi-classical model. (author) 13 refs.; 9 figs.; 2 tabs.

  11. Nuclear matter with pseudo-particle model: static bulk and surface properties

    International Nuclear Information System (INIS)

    Idier, D.; Benhassine, B.; Farine, M.; Remaud, B.; Sebille, F.

    1993-01-01

    Direct calculations of cold and hot nuclear matter (bulk and surface properties) are carried out within the frame of a pseudo-particle model using a Gaussian decomposition of the distribution function. Comparisons with Hartree-Fock calculations, for a large class of effective interactions, show that such a model is reliable to reproduce accurately the equation of state of nuclear matter for large ranges of densities and temperatures. The number of Gaussian per nucleon and the Gaussian widths are critical parameters in that semi-classical model. (author) 13 refs.; 9 figs.; 2 tabs

  12. Nuclear matter with a pseudo-particle model: static bulk and surface properties

    Energy Technology Data Exchange (ETDEWEB)

    Idier, D. (Lab. de Physique Nucleaire CNRS/IN2P3, Univ. de Nantes (France)); Benhassine, B. (Lab. de Physique Nucleaire CNRS/IN2P3, Univ. de Nantes (France)); Farine, M. (Lab. de Physique Nucleaire CNRS/IN2P3, Univ. de Nantes (France)); Remaud, B. (Lab. de Physique Nucleaire CNRS/IN2P3, Univ. de Nantes (France)); Sebille, F. (Lab. de Physique Nucleaire CNRS/IN2P3, Univ. de Nantes (France))

    1993-11-15

    Direct calculations of cold and hot nuclear matter (bulk and surface properties) are carried out within the frame of a pseudo-particle model using a gaussian decomposition of the distribution function. Comparisons with Hartree-Fock calculations, for a large class of effective interactions, show that such a model is reliable to reproduce accurately the equation of state of nuclear matter for large ranges of densities and temperatures. The number of gaussians per nucleon and the gaussian widths are critical parameters in that semi-classical model. (orig.)

  13. light charged particles induced nuclear reaction on some medium weight nuclei for particles applications

    International Nuclear Information System (INIS)

    Mohsena, B.M.A.M.

    2011-01-01

    The radioisotopes of indium, cadmium and tin have many practical and medical applications. Their standard routes for production are proton or deuteron induced reactions on natural or enriched cadmium or tin. The production via 3 He induced reactions on natural or enriched cadmium was rarely discussed. In this study 3 He induced reactions on natural cadmium were measured utilizing the stacked-foil technique. The primary incident beam energy was 27 MeV extracted from the MGC- 20E cyclotron, Debrecen, Hungary.the exciatation functions for the reactions n atCd( 3 He,x) 115g,111m Cd, 117m,g,116m,115m,114m,113m,111g,110m,g,109g,108g,107g In and 117m,113,111,110 Sn were evaluated. The data were compared with the available literature data.Different theoretical nuclear reaction models were also used to predict the cross sections for those reactions. The used models were ALICE-IPPE, TALYS-1.2 and EMPIRE-03. The experimental data were compared also to the theoretical model calculations. The theoretical models did not describe most of the experimental results.The isomeric cross section ratios for the isomeric pairs 117m,g In and 110m,g In were calculated. The isomeric cross section ratio depends on the spins of the states of the interested isomeric pair. The calculated isomeric ratios helped to identify the mechanisms of the reactions involved.The integral yields for some medically relevant isotopes were calculated using the excitation function curves

  14. An independent safety assessment of Department of Energy nuclear reactor facilities: Procedures, operations and maintenance

    International Nuclear Information System (INIS)

    Toto, G.; Lindgren, A.J.

    1981-02-01

    The 1979 accident at the Three Mile Island commercial nuclear power plant has led to a number of studies of nuclear reactors, in both the public and private sectors. One of these is that of the Department of Energy's (DOE) Nuclear Facilities Personnel Qualification and Training (NFPQT) Committee, which has outlined tasks for assessment of 13 reactors owned by DOE and operated by contractors. This report covers one of the tasks, the assessment of procedures, operations, and maintenance at the DOE reactor facilities, based on a review of actual documents used at the reactor sites

  15. Nuclear Gamma-Ray Spectroscopy at the Limit of Particle Stability

    International Nuclear Information System (INIS)

    Dr. Norbert Pietralla

    2006-01-01

    The research project ''Nuclear Gamma-Ray Spectroscopy at the Limit of Particle Stability'' with sponsor ID ''DE-FG02-04ER41334'' started late-summer 2004 and aims at the investigation of highly excited low-spin states of selected key-nuclei in the vicinity of the particle separation threshold by means of high-resolution gamma-ray spectroscopy in electromagnetic excitation reactions. This work addresses nuclear structures with excitation energies close to the binding energy or highly excited off-yrast states in accordance with the NSAC milestones. In 2005 the program was extended towards additional use of virtual photons and theoretical description of the low-lying collective excitations in the well deformed nuclei

  16. Particle induced X-ray emission and complementary nuclear methods for trace element determination; Plenary lecture

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, S A.E. [Lund Univ. (Sweden). Dept. of Nuclear Physics

    1992-03-01

    In this review the state-of-the-art of particle induced X-ray emission (PIXE) methods for the determination of trace elements is described. The developmental work has mostly been carried out in nuclear physics laboratories, where accelerators are available, but now the increased interest has led to the establishment of other dedicated PIXE facilities. The reason for this interest is the versatility, high sensitivity and multi-element capability of PIXE analysis. A further very important advantage is that PIXE can be combined with the microbeam technique, which makes elemental mapping with a spatial resolution of about 1 {mu}m possible. As a technique, PIXE can also be combined with other nuclear reactions such as elastic scattering and particle-induced gamma emission, so that light elements can be determined. The usefulness of PIXE is illustrated by a number of typical applications in biology, medicine, geology, air pollution research, archaeology and the arts. (author).

  17. Emergency planning and response: An independent safety assessment of Department of Energy nuclear reactor facilities

    International Nuclear Information System (INIS)

    Knuth, D.; Boyd, R.

    1981-02-01

    The Department of Energy (DOE) has formed a Nuclear Facilities Personnel Qualification and Training (NFPQT) Committee to assess the implications of the recommendations contained in the President's Commission Report on the Three Mile Island (TMI) Accident (the Kemeny Commission report) that are applicable to DOE's nuclear reactor operations. Thirteen DOE nuclear reactors have been reviewed. The assessments of the 13 facilities are based on information provided by the individual operator organizations and/or cognizant DOE Field Offices. Additional clarifying information was supplied in some, but not all, instances. This report indicates how these 13 reactor facilities measure up in light of the Kemeny and other TMI-related studies and recommendations, particularly those that have resulted in upgraded Nuclear Regulatory Commission (NRC) requirements in the area of emergency planning and response

  18. Full nuclear field theory treatment of two-particle-one-hole-excitations

    International Nuclear Information System (INIS)

    Silvestre-Brac, B.; Liotta, R.J.

    1981-01-01

    The nuclear field theory series is summed up to all orders of perturbation theory including only Tamm-Dancoff vertices for the case of two-particle-one-hole-excitations. It is found that the theory gives the same results as those provided by the shell-model method, but only if all possible basis states are included in the formalism. Applicability of the theory is discussed in a simple model

  19. Nuclear thermal propulsion engine based on particle bed reactor using light water steam as a propellant

    Science.gov (United States)

    Powell, James R.; Ludewig, Hans; Maise, George

    1993-01-01

    In this paper the possibility of configuring a water cooled Nuclear Thermal Propulsion (NTP) rocket, based on a Particle Bed Reactor (PBR) is investigated. This rocket will be used to operate on water obtained from near earth objects. The conclusions reached in this paper indicate that it is possible to configure a PBR based NTP rocket to operate on water and meet the mission requirements envisioned for it. No insurmountable technology issues have been identified.

  20. Japan Charged-Particle Nuclear Reaction Data Group (JCPRG). Progress report. P10

    International Nuclear Information System (INIS)

    Executive Committee of JCPRG

    2001-01-01

    In 2000 the following activities were carried out: compilation of the CNDP (Charged Particle Nuclear Reaction Data); translation of NRDF data into EXFOR data; making of the retrieval systems using Internet and Intelligent Pad for the CPND in both NRDF and EXFOR; distributing the CPND and promoting utilization in Japan; making a new system to transform from NRDF to EXFOR. Preliminary version of a new editing system for compiling and inputting the NRDF data was completed

  1. Nuclear thermal propulsion engine based on particle bed reactor using light water steam as a propellant

    International Nuclear Information System (INIS)

    Powell, J.R.; Ludewig, H.; Maise, G.

    1993-01-01

    In this paper the possibility of configuring a water cooled Nuclear Thermal Propulsion (NTP) rocket, based on a Particle Bed Reactor (PBR) is investigated. This rocket will be used to operate on water obtained from near earth objects. The conclusions reached in this paper indicate that it is possible to configure a PBR based NTP rocket to operate on water and meet the mission requirements envisioned for it. No insurmountable technology issues have been identified

  2. The nuclear localization of low risk HPV11 E7 protein mediated by its zinc binding domain is independent of nuclear import receptors

    International Nuclear Information System (INIS)

    Piccioli, Zachary; McKee, Courtney H.; Leszczynski, Anna; Onder, Zeynep; Hannah, Erin C.; Mamoor, Shahan; Crosby, Lauren; Moroianu, Junona

    2010-01-01

    We investigated the nuclear import of low risk HPV11 E7 protein using 1) transfection assays in HeLa cells with EGFP fusion plasmids containing 11E7 and its domains and 2) nuclear import assays in digitonin-permeabilized HeLa cells with GST fusion proteins containing 11E7 and its domains. The EGFP-11E7 and EGFP-11cE7 39-98 localized mostly to the nucleus. The GST-11E7 and GST-11cE7 39-98 were imported into the nuclei in the presence of either Ran-GDP or RanG19V-GTP mutant and in the absence of nuclear import receptors. This suggests that 11E7 enters the nucleus via a Ran-dependent pathway, independent of nuclear import receptors, mediated by a nuclear localization signal located in its C-terminal domain (cNLS). This cNLS contains the zinc binding domain consisting of two copies of Cys-X-X-Cys motif. Mutagenesis of Cys residues in these motifs changed the localization of the EGFP-11cE7/-11E7 mutants to cytoplasmic, suggesting that the zinc binding domain is essential for nuclear localization of 11E7.

  3. Development and analysis of startup strategies for particle bed nuclear rocket engine

    Science.gov (United States)

    Suzuki, David E.

    1993-06-01

    The particle bed reactor (PBR) nuclear thermal propulsion rocket engine concept is the focus of the Air Force's Space Nuclear Thermal Propulsion program. While much progress has been made in developing the concept, several technical issues remain. Perhaps foremost among these concerns is the issue of flow stability through the porous, heated bed of fuel particles. There are two complementary technical issues associated with this concern: the identification of the flow stability boundary and the design of the engine controller to maintain stable operation. This thesis examines a portion of the latter issue which has yet to be addressed in detail. Specifically, it develops and analyzes general engine system startup strategies which maintain stable flow through the PBR fuel elements while reaching the design conditions as quickly as possible. The PBR engine studies are conducted using a computer model of a representative particle bed reactor and engine system. The computer program utilized is an augmented version of SAFSIM, an existing nuclear thermal propulsion modeling code; the augmentation, dubbed SAFSIM+, was developed by the author and provides a more complete engine system modeling tool.

  4. Method for calculating the characteristics of nuclear reactions with composite particle

    International Nuclear Information System (INIS)

    Zelenskaya, N.S.

    1978-01-01

    The purpose of the lectures is to attempt to give a brief review of the present status of the theory of nuclear reactions involving composite particles (heavy ions, 6 Li, 7 Li, and 9 Be ions, α-particles). In order to analyze such reactions, one should employ and ''exact'' method of distorted waves with a finite radius of interaction. Since the zero radius approximation is valid only at low momentum transfer, its rejection immediately includes all possible transferred momenta and consequently, the reaction mechanisms different from the usual cluster stripping we shall discuss a sufficiently general formalism of the distorted waves method, which does not use additional assumptions about the smaliness of the region of interaction between particles and about the possible reaction mechanisms. We shall also discuss all physical simplifications introduced in specific particular codes and the ranges of their applicability will be established. (author)

  5. The particle analysis based on FT-TIMS technique for swipe sample under the frame of nuclear safeguard

    International Nuclear Information System (INIS)

    Yang Tianli; Liu Xuemei; Liu Zhao; Tang Lei; Long Kaiming

    2008-06-01

    Under the frame of nuclear safeguard, the particles analysis for swipe sample is an advance mean to detect the undeclared uranium enriched facilities and undeclared uranium enriched activity. The technique of particle analysis based on fission track-thermal ionization mass spectrometry (FT-TIMS) for swipe sample have been built. The reliability and the experimental background for selecting particles consisting of uranium from swipe sample by FT method have been verified. In addition, the utilization coefficient of particles on the surface of swipe sample have also been tested. These works have provided the technique support for application in the area of nuclear verification. (authors)

  6. Effect of a generalized particle momentum distribution on plasma nuclear fusion rates

    International Nuclear Information System (INIS)

    Kim, Yeong E.; Zubarev, Alexander L.

    2006-01-01

    We investigate the effect of a generalized particle momentum distribution derived by Galitskii and Yakimets (GY) on nuclear reaction rates in plasma. We derive an approximate semi-analytical formula for nuclear fusion reaction rate between nuclei in a plasma (quantum plasma nuclear fusion; or QPNF). The QPNF formula is applied to calculate deuteron-deuteron fusion rate in a plasma, and the results are compared with the results calculated with the conventional Maxwell-Boltzmann velocity distribution. As an application, we investigate the deuteron-deuteron fusion rate for mobile deuterons in a deuterated metal/alloy. The calculated deuteron-deuteron fusion rates at low energies are enormously enhanced due to the modified tail of the GY's generalized momentum distribution. Our preliminary estimates indicate also that the deuteron-lithium (D+Li) fusion rate and the proton-lithium (p+Li) fusion rate in a metal/alloy at ambient temperatures are also substantially enhanced. (author)

  7. Double beta decays and related subjects for particle and nuclear physics

    International Nuclear Information System (INIS)

    Ejiri, Hiroyasu

    1991-01-01

    Present status and some perspectives in 1990's are briefly given on double beta decays and related subjects. Subjects discussed are as follows I) Double beta decays without neutrinos, which require lepton number non-conservations and finite neutrino mass. II) Double beta decays followed by two neutrinos. III) Double weak processes with strangeness change ΔS = 2, leading to the H particle with 6 quarks of ss uu dd. IV) Charge non-conservation and electron decays. These are very rare nuclear processes studied by Ultra RAre-process NUclear Spectroscopy (URANUS). It is shown that URANUS is an important detector frontier of non-accelerator nuclear physics in 1990's. (orig.)

  8. Nuclear steam supply system KLT-40 enhanced safety as independent power supply source. Employment prospects

    International Nuclear Information System (INIS)

    Polunichev, V.I.; Sayanov, D.G.; Ardabievsky, A.A.

    1993-01-01

    High quality of KLT-40 nuclear steam supply system (NSSS) providing enhanced safety is attained owing to the development and operation experience of equipments and systems in Soviet nuclear icebreakers. First of all they are the operating nuclear-powered icebreakers open-quotes Arktikaclose quotes, open-quotes Sibirclose quotes, open-quotes Rossiyaclose quotes, open-quotes Sovetsky Soyuzclose quotes, the limited draught icebreakers of joint Soviet-Finnish manufacturing open-quotes Taimyrclose quotes open-quotes Vaigachclose quotes. 30-years trouble-free operation of icebreaker open-quotes Leninclose quotes, the ancestor of nuclear powered fleet, is unprecedented. Operation life of individual equipment items amounts to 107000 hours, that testifies to high reliability and life characteristics of NSSS. Trouble-free operation of the nuclear-powered icebreakers' reactor plants (RPs) exceeded 130 reactor years, that proves high quality of design decisions being underlain in the basis of the KLT-40 NSSS for the lighter-cargo carrier open-quotes Sevmorputclose quotes, which was put into operation into 1988. Besides it testifies to the expediency of KLT-40 NSSS employment as a power source in different power installations. The KLT-40 is a reactor plant with a pwr type reactor. The design is described in detail with diagrams

  9. An estimation of percentage of pion, kaon and other particles produced in nuclear emulsion - a simulated approach

    International Nuclear Information System (INIS)

    Bhattacharyya, Swarnapratim; Haiduc, Maria; Neagu, Alina Tania; Firu, Elena

    2014-01-01

    Multiparticle production in both high-energy nuclear and particle collisions is still a mystery, as far as the understanding of the dynamics of the production of secondary particles, especially of the soft varieties, is concerned. Of the various types of particles produced, mesons, especially the π-mesons, constitute, in practical terms, the near totality of the produced particles. Along with pions, in high-energy interactions kaons, hyperons and other mesons are also produced. In online experiments such as RHIC or LHC all the mesons can be detected. However, in emulsion experiments, there is no identification of the produced particles making a study of particle ratio fluctuations or net charge fluctuations impossible. In emulsion experiments, therefore, it is not possible to distinguish between pions and other mesons. There is one way to look at the compositions of the particles produced in high-energy nucleus-nucleus interactions in nuclear emulsion track detector

  10. Radioactive Pollution Estimate for Fukushima Nuclear Power Plant by a Particle Model

    Science.gov (United States)

    Saito, Keisuke; Ogawa, Susumu

    2016-06-01

    On Mar 12, 2011, very wide radioactive pollution occurred by a hydrogen explosion in Fukushima Nuclear Power Plant. A large amount of radioisotopes started with four times of explosions. With traditional atmospheric diffusion models could not reconstruct radioactive pollution in Fukushima. Then, with a particle model, this accident was reconstructed from meteorological archive and Radar- AMeDAS. Calculations with the particle model were carried out for Mar 12, 15, 18 and 20 when east southeast winds blew for five hours continuously. Meteorological archive is expressed by wind speeds and directions in five-km grid every hour with eight classes of height till 3000 m. Radar- AMeDAS is precipitation data in one-km grid every thirty minutes. Particles are ten scales of 0.01 to 0.1 mm in diameter with specific weight of 2.65 and vertical speeds given by Stokes equation. But, on Mar 15, it rained from 16:30 and then the particles fell down at a moment as wet deposit in calculation. On the other hand, the altitudes on the ground were given by DEM with 1 km-grid. The spatial dose by emitted radioisotopes was referred to the observation data at monitoring posts of Tokyo Electric Power Company. The falling points of radioisotopes were expressed on the map using the particle model. As a result, the same distributions were obtained as the surface spatial dose of radioisotopes in aero-monitoring by Ministry of Education, Culture, Sports, Science and Technology. Especially, on Mar 15, the simulated pollution fitted to the observation, which extended to the northwest of Fukushima Daiichi Nuclear Power Plant and caused mainly sever pollution. By the particle model, the falling positions on the ground were estimated each particle size. Particles with more than 0.05 mm of size were affected by the topography and blocked by the mountains with the altitudes of more than 700 m. The particle model does not include the atmospheric stability, the source height, and deposit speeds. The

  11. What future for Euratom as the UK prepares for its 'nuclear independence'?

    International Nuclear Information System (INIS)

    Shepherd, John

    2017-01-01

    UK government ministers have been keeping European leaders guessing over what their negotiating position will be when formal talks start about the 'divorce' from the European Union. However, for the nuclear energy community, there was one very certain statement in recent weeks about what Brexit will also mean: withdrawal from the Euratom Treaty.

  12. What future for Euratom as the UK prepares for its 'nuclear independence'?

    Energy Technology Data Exchange (ETDEWEB)

    Shepherd, John [nuclear 24, Redditch (United Kingdom)

    2017-03-15

    UK government ministers have been keeping European leaders guessing over what their negotiating position will be when formal talks start about the 'divorce' from the European Union. However, for the nuclear energy community, there was one very certain statement in recent weeks about what Brexit will also mean: withdrawal from the Euratom Treaty.

  13. The independent nuclear state. The United States, Britain and the military atom

    International Nuclear Information System (INIS)

    Simpson, J.

    1983-01-01

    A chronological account and overview are presented of the 40-year history of British military research, development and production work in atomic energy. The United Kingdom's efforts in this field have always had close links with equivalent activities in the United States, and have often been conducted on a mutually co-operative basis. This book contains descriptions of the technical evolution of British nuclear weapon designs and production models, estimates of annual output figures for fissile material and weapon types, and indications of the nature of the weapon-testing programme. Decision-points are charted. The impact of the agreements with the United States, both upon weapon development and production programmes and upon stockpiling, is analysed, as well as their effects upon the nuclear submarine programme. The impact of later events upon Anglo-American relations is identified, together with the recent British attempts to move to a closer political association with Europe. The study concludes by evaluating the essential nature of four decades of United Kingdom military nuclear development, and identifying the practical limits imposed by past policies upon any attempt by a British government to implement a policy of unilateral nuclear disarmament. (author)

  14. Non-Born-Oppenheimer electronic and nuclear densities for a Hooke-Calogero three-particle model: non-uniqueness of density-derived molecular structure.

    Science.gov (United States)

    Ludeña, E V; Echevarría, L; Lopez, X; Ugalde, J M

    2012-02-28

    We consider the calculation of non-Born-Oppenheimer, nBO, one-particle densities for both electrons and nuclei. We show that the nBO one-particle densities evaluated in terms of translationally invariant coordinates are independent of the wavefunction describing the motion of center of mass of the whole system. We show that they depend, however, on an arbitrary reference point from which the positions of the vectors labeling the particles are determined. We examine the effect that this arbitrary choice has on the topology of the one-particle density by selecting the Hooke-Calogero model of a three-body system for which expressions for the one-particle densities can be readily obtained in analytic form. We extend this analysis to the one-particle densities obtained from full Coulomb interaction wavefunctions for three-body systems. We conclude, in view of the fact that there is a close link between the choice of the reference point and the topology of one-particle densities that the molecular structure inferred from the topology of these densities is not unique. We analyze the behavior of one-particle densities for the Hooke-Calogero Born-Oppenheimer, BO, wavefunction and show that topological transitions are also present in this case for a particular mass value of the light particles even though in the BO regime the nuclear masses are infinite. In this vein, we argue that the change in topology caused by variation of the mass ratio between light and heavy particles does not constitute a true indication in the nBO regime of the emergence of molecular structure.

  15. Climate effects of a hypothetical regional nuclear war: Sensitivity to emission duration and particle composition

    Science.gov (United States)

    Pausata, Francesco S. R.; Lindvall, Jenny; Ekman, Annica M. L.; Svensson, Gunilla

    2016-11-01

    Here, we use a coupled atmospheric-ocean-aerosol model to investigate the plume development and climate effects of the smoke generated by fires following a regional nuclear war between emerging third-world nuclear powers. We simulate a standard scenario where 5 Tg of black carbon (BC) is emitted over 1 day in the upper troposphere-lower stratosphere. However, it is likely that the emissions from the fires ignited by bomb detonations include a substantial amount of particulate organic matter (POM) and that they last more than 1 day. We therefore test the sensitivity of the aerosol plume and climate system to the BC/POM ratio (1:3, 1:9) and to the emission length (1 day, 1 week, 1 month). We find that in general, an emission length of 1 month substantially reduces the cooling compared to the 1-day case, whereas taking into account POM emissions notably increases the cooling and the reduction of precipitation associated with the nuclear war during the first year following the detonation. Accounting for POM emissions increases the particle size in the short-emission-length scenarios (1 day/1 week), reducing the residence time of the injected particle. While the initial cooling is more intense when including POM emission, the long-lasting effects, while still large, may be less extreme compared to the BC-only case. Our study highlights that the emission altitude reached by the plume is sensitive to both the particle type emitted by the fires and the emission duration. Consequently, the climate effects of a nuclear war are strongly dependent on these parameters.

  16. Hybrid particle swarm optimization algorithm and its application in nuclear engineering

    International Nuclear Information System (INIS)

    Liu, C.Y.; Yan, C.Q.; Wang, J.J.

    2014-01-01

    Highlights: • We propose a hybrid particle swarm optimization algorithm (HPSO). • Modified Nelder–Mead simplex search method is applied in HPSO. • The algorithm has a high search precision and rapidly calculation speed. • HPSO can be used in the nuclear engineering optimization design problems. - Abstract: A hybrid particle swarm optimization algorithm with a feasibility-based rule for solving constrained optimization problems has been developed in this research. Firstly, the global optimal solution zone can be obtained through particle swarm optimization process, and then the refined search of the global optimal solution will be achieved through the modified Nelder–Mead simplex algorithm. Simulations based on two well-studied benchmark problems demonstrate the proposed algorithm will be an efficient alternative to solving constrained optimization problems. The vertical electrical heating pressurizer is one of the key components in reactor coolant system. The mathematical model of pressurizer has been established in steady state. The optimization design of pressurizer weight has been carried out through HPSO algorithm. The results show the pressurizer weight can be reduced by 16.92%. The thermal efficiencies of conventional PWR nuclear power plants are about 31–35% so far, which are much lower than fossil fueled plants based in a steam cycle as PWR. The thermal equilibrium mathematic model for nuclear power plant secondary loop has been established. An optimization case study has been conducted to improve the efficiency of the nuclear power plant with the proposed algorithm. The results show the thermal efficiency is improved by 0.5%

  17. Device for fracturing silicon-carbide coatings on nuclear-fuel particles

    Science.gov (United States)

    Turner, L.J.; Willey, M.G.; Tiegs, S.M.; Van Cleve, J.E. Jr.

    This invention is a device for fracturing particles. It is designed especially for use in hot cells designed for the handling of radioactive materials. In a typical application, the device is used to fracture a hard silicon-carbide coating present on carbon-matrix microspheres containing nuclear-fuel materials, such as uranium or thorium compounds. To promote remote control and facilitate maintenance, the particle breaker is pneumatically operated and contains no moving parts. It includes means for serially entraining the entrained particles on an anvil housed in a leak-tight chamber. The flow rate of the gas is at a value effecting fracture of the particles; preferably, it is at a value fracturing them into product particulates of fluidizable size. The chamber is provided with an outlet passage whose cross-sectional area decreases in the direction away from the chamber. The outlet is connected tangentially to a vertically oriented vortex-flow separator for recovering the product particulates entrained in the gas outflow from the chamber. The invention can be used on a batch or continuous basis to fracture the silicon-carbide coatings on virtually all of the particles fed thereto.

  18. Method for fracturing silicon-carbide coatings on nuclear-fuel particles

    Science.gov (United States)

    Turner, Lloyd J.; Willey, Melvin G.; Tiegs, Sue M.; Van Cleve, Jr., John E.

    1982-01-01

    This invention is a device for fracturing particles. It is designed especially for use in "hot cells" designed for the handling of radioactive materials. In a typical application, the device is used to fracture a hard silicon-carbide coating present on carbon-matrix microspheres containing nuclear-fuel material, such as uranium or thorium compounds. To promote remote control and facilitate maintenance, the particle breaker is pneumatically operated and contains no moving parts. It includes means for serially entraining the entrained particles on an anvil housed in a leak-tight chamber. The flow rate of the gas is at a value effecting fracture of the particles; preferably, it is at a value fracturing them into product particulates of fluidizable size. The chamber is provided with an outlet passage whose cross-sectional area decreases in the direction away from the chamber. The outlet is connected tangentially to a vertically oriented vortex-flow separator for recovering the product particulates entrained in the gas outflow from the chamber. The invention can be used on a batch or continuous basis to fracture the silicon-carbide coatings on virtually all of the particles fed thereto.

  19. Registration of alpha particles in Makrofol-E nuclear track detectors

    Energy Technology Data Exchange (ETDEWEB)

    Rammah, Y.S. [Physics Department, Faculty of Science, Menoufia University, Shebin El-Koom (Egypt); Abdalla, Ayman M., E-mail: aymanabdalla62@hotmail.com [Physics Department, Faculty of Sciences and Arts, Najran University, P. O. Box. 11001, Najran (Saudi Arabia); Promising Centre for Sensors and Electronic Devices, Faculty of Arts and Sciences, Najran University (Saudi Arabia); Ashraf, O., E-mail: osama.ashraf@edu.asu.edu.eg [Physics Department, Faculty of Education, Ain Shams University, Cairo 11575 (Egypt); Ashry, A.H. [Physics Department, Faculty of Education, Ain Shams University, Cairo 11575 (Egypt)

    2016-06-15

    Highlights: • Makrofol-E detectors have been irradiated with alpha particles and fission fragments. • Fast detection of alpha particles in Makrofol-E detectors. • Bulk etching rate was calculated from fission track diameters. - Abstract: Fast detection of alpha particles in the range from 1 to 5 MeV in Makrofol-E polycarbonate nuclear track detectors (PCTDs) using a new chemical etchant was investigated. {sup 252}Cf and {sup 241}Am-thin open sources were used for irradiating Makrofol-E detectors with fission fragments and alpha particles in air at normal pressure and temperature (NPT). A chain of experimental work has been carried out using new etchants to register alpha particle in short time in Makrofol-E polycarbonate detectors. The etching efficiency were exhibited a clear dependence on the amount of methanol in the etching solution and etching time. The optimized chemical condition obtained at this stage of development for 200 μm Makrofol-E detectors are (8 ml of 10 N NaOH + 2 ml CH{sub 3}OH) etching solutions at 60 °C for 3 h. In this study; it is possible to observe energy detection windows for Makrofol-E detectors according to applied etching duration. Makrofol-E introduced the characteristic Bragg peak, which indicates the advantages of this detector as alpha spectrometer. Consequently, the suggested new etchant can be developed for heavy ions detection and monitoring radon levels and its daughters.

  20. New developments in image-based characterization of coated particle nuclear fuel

    Science.gov (United States)

    Price, Jeffery R.; Aykac, Deniz; Hunn, John D.; Kercher, Andrew K.; Morris, Robert N.

    2006-02-01

    We describe in this paper new developments in the characterization of coated particle nuclear fuel using optical microscopy and digital imaging. As in our previous work, we acquire optical imagery of the fuel pellets in two distinct manners that we refer to as shadow imaging and cross-sectional imaging. In shadow imaging, particles are collected in a single layer on an optically transparent dish and imaged using collimated back-lighting to measure outer surface characteristics only. In cross-sectional imaging, particles are mounted in acrylic epoxy and polished to near-center to reveal the inner coating layers for measurement. For shadow imaging, we describe a curvaturebased metric that is computed from the particle boundary points in the FFT domain using a low-frequency parametric representation. We also describe how missing boundary points are approximated using band-limited interpolation so that the FFT can be applied. For cross-section imaging, we describe a new Bayesian-motivated segmentation scheme as well as a new technique to correct layer measurements for the fact that we cannot observe the true mid-plane of the approximately spherical particles.

  1. Production and characterization of monodisperse uranium particles for nuclear safeguards applications

    International Nuclear Information System (INIS)

    Knott, Alexander

    2016-01-01

    Environmental sampling is a very effective measure to detect undeclared nuclear activities. Generally, samples are taken as swipe samples on cotton. These swipes contain minute quantities of particulates which have an inherent signature of their production and release scenario. These inspection samples are assessed for their morphology, elemental composition and their isotopic vectors. Mass spectrometry plays a crucial role in determining the isotopic ratios of uranium. Method validation and instrument calibration with well-characterized quality control (QC)-materials, reference materials (RMs) and certified reference materials (CRMs) ensures reliable data output. Currently, the availability of suitable well defined microparticles containing uranium and plutonium reference materials is very limited. Primarily, metals, oxides and various uranium and plutonium containing solutions are commercially available. Therefore, the IAEA's Safeguards Analytical Services (SGAS) cooperates with the Institute of Nuclear Waste Management and Reactor Safety (IEK-6) at the Forschungszentrum Juelich GmbH in a joint task entitled ''Production of Particle Reference Materials''. The work presented in this thesis has been partially funded by the IAEA, Forschungszentrum Juelich GmbH and the Federal Ministry of Economic Affairs and Energy (BMWi) through the ''Joint Program on the Technical Development and Further Improvement of IAEA Safeguards between the Government of the Federal Republic of Germany and the IAEA''. The first step towards monodisperse microparticles was the development of pure uranium oxide particles made from certified reference materials. The focus of the dissertation is (1) the implementation of a working setup to produce monodisperse uranium oxide particles and (2) the characterization of these particles towards the application as QC-material. Monodisperse uranium oxide particles were produced by spray pyrolysis. It was demonstrated that the particle size can be

  2. Independent assembly technology for DCS safety equipment in nuclear power plant

    International Nuclear Information System (INIS)

    Hao Aixia

    2014-01-01

    A independent assembly technology of identification and verification was proposed, which included special process, wiring process and verification process. The safety reliability and practicability of the proposed technology were verified according to the application in FirmSys assembly implemented by China Techenergy Co., Ltd. (author)

  3. Factorisation scale independence, the connection between alternative explanations of the EMC effect and QCD predictions for nuclear properties

    International Nuclear Information System (INIS)

    Close, F.E.; Roberts, R.G.; Ross, G.G.

    1987-05-01

    Different models are examined for deep inelastic scattering in nuclei in the context of the operator product expansion where the operator matrix elements involve a factorisation scale characterising the separation of short or long distance physics. By exploiting the independence of physical quantities upon this scale seemingly different models for the nucleus can be connected, such as dynamical rescaling and the standard convolution models of nuclear physics, allowing nuclear properties to be simply expressed in terms of the anomalous dimensions of QCD. A discussion is carried out of how non-convolution contributions may also be described by dynamical rescaling and it is shown how to extend dynamical rescaling to describe spin dependent quantities. (author)

  4. ATTILA (All Type Target Independent Lund Algorithm) for nuclear collisions at ≅ 200 AGeV

    International Nuclear Information System (INIS)

    Gyulassy, M.; Lawrence Berkeley Lab., CA

    1987-08-01

    The Lund string model, Fritiof, is applied in the form of a Monte-Carlo event generator, ATTILA, to nuclear collisions in the 200 AGeV range. We study how uncertainties at the pp level amplify at the AB level and compare preliminary CERN data on multiplicity, transverse energy, and veto energy distributions to this linear extrapolation scheme from pp to AB dynamics. (orig.)

  5. A fuzzy controller design for nuclear research reactors using the particle swarm optimization algorithm

    International Nuclear Information System (INIS)

    Coban, Ramazan

    2011-01-01

    Research highlights: → A closed-loop fuzzy logic controller based on the particle swarm optimization algorithm was proposed for controlling the power level of nuclear research reactors. → The proposed control system was tested for various initial and desired power levels, and it could control the reactor successfully for most situations. → The proposed controller is robust against the disturbances. - Abstract: In this paper, a closed-loop fuzzy logic controller based on the particle swarm optimization algorithm is proposed for controlling the power level of nuclear research reactors. The principle of the fuzzy logic controller is based on the rules constructed from numerical experiments made by means of a computer code for the core dynamics calculation and from human operator's experience and knowledge. In addition to these intuitive and experimental design efforts, consequent parts of the fuzzy rules are optimally (or near optimally) determined using the particle swarm optimization algorithm. The contribution of the proposed algorithm to a reactor control system is investigated in details. The performance of the controller is also tested with numerical simulations in numerous operating conditions from various initial power levels to desired power levels, as well as under disturbance. It is shown that the proposed control system performs satisfactorily under almost all operating conditions, even in the case of very small initial power levels.

  6. Nuclear expression of lysyl oxidase enzyme is an independent prognostic factor in rectal cancer patients

    DEFF Research Database (Denmark)

    Liu, Na; Cox, Thomas R; Cui, Weiyingqi

    2017-01-01

    Emerging evidence has implicated a pivotal role for lysyl oxidase (LOX) in cancer progression and metastasis. Whilst the majority of work has focused on the extracellular matrix cross-linking role of LOX, the exact function of intracellular LOX localisation remains unclear. In this study, we anal...... the nucleus of colon cancer cell lines by confocal microscopy and Western blot. Our results show a powerful link between nuclear LOX expression in tumours and patient survival, and offer a promising prognostic biomarker for rectal cancer patients....... analysed the LOX expression patterns in the nuclei of rectal cancer patient samples and determined the clinical significance of this expression. Nuclear LOX expression was significantly increased in patient lymph node metastases compared to their primary tumours. High nuclear LOX expression in tumours......Emerging evidence has implicated a pivotal role for lysyl oxidase (LOX) in cancer progression and metastasis. Whilst the majority of work has focused on the extracellular matrix cross-linking role of LOX, the exact function of intracellular LOX localisation remains unclear. In this study, we...

  7. Particle swarm optimization with random keys applied to the nuclear reactor reload problem

    Energy Technology Data Exchange (ETDEWEB)

    Meneses, Anderson Alvarenga de Moura [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Programa de Engenharia Nuclear; Fundacao Educacional de Macae (FUNEMAC), RJ (Brazil). Faculdade Professor Miguel Angelo da Silva Santos; Machado, Marcelo Dornellas; Medeiros, Jose Antonio Carlos Canedo; Schirru, Roberto [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Programa de Engenharia Nuclear]. E-mails: ameneses@con.ufrj.br; marcelo@lmp.ufrj.br; canedo@lmp.ufrj.br; schirru@lmp.ufrj.br

    2007-07-01

    In 1995, Kennedy and Eberhart presented the Particle Swarm Optimization (PSO), an Artificial Intelligence metaheuristic technique to optimize non-linear continuous functions. The concept of Swarm Intelligence is based on the socials aspects of intelligence, it means, the ability of individuals to learn with their own experience in a group as well as to take advantage of the performance of other individuals. Some PSO models for discrete search spaces have been developed for combinatorial optimization, although none of them presented satisfactory results to optimize a combinatorial problem as the nuclear reactor fuel reloading problem (NRFRP). In this sense, we developed the Particle Swarm Optimization with Random Keys (PSORK) in previous research to solve Combinatorial Problems. Experiences demonstrated that PSORK performed comparable to or better than other techniques. Thus, PSORK metaheuristic is being applied in optimization studies of the NRFRP for Angra 1 Nuclear Power Plant. Results will be compared with Genetic Algorithms and the manual method provided by a specialist. In this experience, the problem is being modeled for an eight-core symmetry and three-dimensional geometry, aiming at the minimization of the Nuclear Enthalpy Power Peaking Factor as well as the maximization of the cycle length. (author)

  8. Particle swarm optimization with random keys applied to the nuclear reactor reload problem

    International Nuclear Information System (INIS)

    Meneses, Anderson Alvarenga de Moura; Fundacao Educacional de Macae; Machado, Marcelo Dornellas; Medeiros, Jose Antonio Carlos Canedo; Schirru, Roberto

    2007-01-01

    In 1995, Kennedy and Eberhart presented the Particle Swarm Optimization (PSO), an Artificial Intelligence metaheuristic technique to optimize non-linear continuous functions. The concept of Swarm Intelligence is based on the socials aspects of intelligence, it means, the ability of individuals to learn with their own experience in a group as well as to take advantage of the performance of other individuals. Some PSO models for discrete search spaces have been developed for combinatorial optimization, although none of them presented satisfactory results to optimize a combinatorial problem as the nuclear reactor fuel reloading problem (NRFRP). In this sense, we developed the Particle Swarm Optimization with Random Keys (PSORK) in previous research to solve Combinatorial Problems. Experiences demonstrated that PSORK performed comparable to or better than other techniques. Thus, PSORK metaheuristic is being applied in optimization studies of the NRFRP for Angra 1 Nuclear Power Plant. Results will be compared with Genetic Algorithms and the manual method provided by a specialist. In this experience, the problem is being modeled for an eight-core symmetry and three-dimensional geometry, aiming at the minimization of the Nuclear Enthalpy Power Peaking Factor as well as the maximization of the cycle length. (author)

  9. The origin, composition and distribution of 'hot particles' derived from the nuclear industry and dispersed in the environment

    International Nuclear Information System (INIS)

    Hamilton, E.I.; Clifton, R.J.

    1987-10-01

    Today, recent sediments of the Esk estuary, Cumbria, contain few hot particles derived from BNF compared with those deposited during peak releases of 1972-74. Overall the hot particles account for about 10% of the total alpha particle activity of the sediments. At some horizons, in buried sediments, concentrations of hot particles probably represent rapid transport on the sea surface under conditions of minimum erosion. Similar particles, usually less well defined, occur in accreting sediments but are corroded. Representative types of the most radioactive particles have been isolated and contain Pu, Am and Cm but only trace amounts of naturally occuring alpha emitters. Microprobe analysis of these particles often shows the presence of fairly pure uranium as the major element. On the basis of radioactivity and elemental composition many of these particles appear to be irradiated nuclear fuel debris. (author)

  10. Thresholds and Q values of nuclear reactions induced by neutrons, protons, deuterons, tritons, 3He ions, alpha particles, and photons

    International Nuclear Information System (INIS)

    Howerton, R.J.

    1981-01-01

    The 1977 Wapstra and Bos nuclear mass data tables were used to derive tables for thresholds and Q values of nuclear reactions induced by neutrons, protons, deuterons, tritons, 3 He ions, alpha particles, and photons. The tables are displayed on microfiche included with the report

  11. Investigation of cumulative Λ0-particle properties nuclear scaling and search for baryonrich quark-gluon plasma

    International Nuclear Information System (INIS)

    Degtyarenko, P.V.; Efremenko, Yu.V.; Fedorov, V.B.

    1991-01-01

    Energy and A-dependencies of cumulative Λ 0 particle spectra for the particles emitted at angle 90 deg have been studied by means of electronic method; its polarization has been determined. Obtained data are analyzed both in terms of nuclear scaling phenomena and of possible existence of baryonrich quark-gluon plasma and are compared with other known data on cumulative particle formation. 31 refs.; 8 figs

  12. Position sensitive photon detectors for nuclear physics, particle physics and healthcare applications

    International Nuclear Information System (INIS)

    Seitz, B

    2012-01-01

    Modern experiments in hadronic physics require detector systems capable of identifying and reconstructing all final-state particles and their momentum vectors. Imaging Cherenkov counters (RICH and DIRC) are frequently employed in nuclear and particle physics experiments. These detectors require high-rate, single-photon capable light detection system with sufficient granularity and position resolution. Several candidate systems are available, ranging from multi-anode photomultiplier tubes to micro-channel plate systems to silicon photomultipliers. Each of these detection solutions has particular advantages and disadvantages. Detailed studies of rate dependence, cross-talk, time-resolution and position resolution for a range of available photon detection solutions are presented. These properties make these photon detection systems ideal for radionuclide imaging applications. Cherenkov radiation can also be used for medical imaging applications. Two different applications using the Cherenkov effect for radionuclide imaging will be reviewed.

  13. 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.

  14. Influence of the particle discriminator for producing the microporous nuclear track etched membrane

    International Nuclear Information System (INIS)

    Thongphud, Apaporn; Ratanatongchai, Wichian; Supaphol, Pitt; Visal-athaphand, Pinpan

    2005-10-01

    The particle discriminator was used to focus the fission fragments from nuclear fission reaction between thermal neutron from the Thai Research Reactor and U-235 in uranium screen to strike almost normally to the polycarbonate (PC) film. The latent tracks in the thin 15 mm PC film were revealed after etching in 6N NaOH solution at 70 o C for 60 min. It was found that the tracks were porous. The porosity was more discrete and the pore shape was more circular as well. The track diameter was measured 3.73 +- 0.32 mm. It was also found that using particle discriminators with increasing thickness during exposure gives fewer pores in the PC film, after chemical etching under the same condition as above

  15. Analysis of startup strategies for a particle bed reactor nuclear rocket engine

    Science.gov (United States)

    Suzuki, D. E.

    1993-06-01

    This paper develops and analyzes engine system startup strategies for a particle bed reactor (PBR) nuclear rocket engine. The strategies are designed to maintain stable flow through the PBR fuel element while reaching the design conditions as quickly as possible. The analyses are conducted using a computer model of a representative particle bed reactor and engine system. Elements of the startup strategy considered include: the coordinated control of reactor power and coolant flow; turbine inlet temperature and flow control; and use of an external starter system. The simulation results indicate that the use of an external starter system enables the engine to reach design conditions very quickly while maintaining the flow well away from the unstable regime. If a bootstrap start is used instead, the transient does not progress as fast and approaches closer to the unstable flow regime, but allows for greater engine reusability. These results can provide important information for engine designers and mission planners.

  16. Light particle emission as a probe of reaction mechanism and nuclear excitation

    International Nuclear Information System (INIS)

    Guerreau, D.

    1989-01-01

    The central part of these lectures will be dealing with the problem of energy dissipation. A good understanding of the mechanisms for the dissipation requires to study both peripheral and central collisions or, in other words, to look at the impact paramenter dependence. This should also provide valuable information on the time scale. In order to probe the reaction mechanism and nuclear excitation, one of the most powerful tool is unquestionably the observation of light particle emission, including neutrons and charged particles. Several examples will be discussed related to peripheral collisions (the fate of transfer reactions, the excitation energy generation, the production of projectile-like fragments) as well as inner collisions for which extensive studies have demonstrated the strength of intermediate energy heavy ions for the production of very hot nuclei and detailed study of their decay properties

  17. Effective mass of a #betta#-particle in nuclear matter and OBE #betta#-n interactions

    International Nuclear Information System (INIS)

    Bando, Hiroharu; Nagata, Sinobu.

    1982-01-01

    The effective mass of a lambda particle (M sub( lambda )*) in nuclear matter is investigated within the framework of the lowest-order Brueckner theory by employing the Nijmegen OBE lambda -N interaction model D and F. The non-locality mass (M tilde sub( lamda )) and the energy mass (anti M sub( lambda )) are evaluated and discussed in the light of the characteristics of the two models. In comparison with the model D, the model F yields smaller anti M sub( lambda ) and larger anti M sub( lamb da ) reflecting the stronger Majorana exchange force and the stronger lambda N- sigma N coupling tensor force. Final results of M sub( lambda )*/M sub( lambda ) are 0.85 for D and 0.79 for F. In view of the effective lambda mass inferred from observed properties of the single particle potential for lambda , the model D interaction seems to be more adequate. (author)

  18. Modifications of the optical properties for DAM-ADC nuclear track detector exposed to alpha particles

    Science.gov (United States)

    Rammah, Y. S.; Awad, E. M.

    2018-05-01

    Modifications of the optical properties of diallyl maleate-allyl diglycol carbonate (DAM-ADC) nuclear detector induced by alpha particles are described. DAM-ADC samples were irradiated perpendicularly by thin 241Am disk source that emits alpha particles with 5.48 MeV. The optical absorption has been measured using the ultraviolet-visible (UV-1100) spectroscopy. It was found that DAM-ADC polymer shows substantial modifications in its optical characteristics upon irradiated with alpha particles with different energies. The optical energy band gap (Egap) for the detector was calculated for the direct and the indirect allowed transitions in K-space using two approaches (Tauc's model and absorption spectrum fitting (ASF) method). Urbach's energy (Ea), number of carbon atoms per conjugated length (N), number of carbon atoms per cluster (M), and refractive index (n) for the present samples were determined. Results reveal that the values of energy gap in direct transition are greater than those of indirect, before and after irradiation. (Egap), (Ea), (N), (M), and (n) of the present samples are changed significantly with irradiation time and value of alpha energy. Results reflect the possibility of using DAM-ADC polymer track detectors to estimate alpha particle energies using the variation of the absorbance.

  19. Photoluminescence detection of alpha particle using DAM-ADC nuclear detector

    Energy Technology Data Exchange (ETDEWEB)

    Abdalla, Ayman M., E-mail: aymanabdalla62@hotmail.com [Department of Physics, College of Science and Arts, Najran University, P.O. Box 1988, Najran 11001 (Saudi Arabia); Promising Centre for Sensors and Electronic Devices (PCSED), Najran University, P.O. Box: 1988, Najran 11001 (Saudi Arabia); Harraz, Farid A., E-mail: fharraz68@yahoo.com [Promising Centre for Sensors and Electronic Devices (PCSED), Najran University, P.O. Box: 1988, Najran 11001 (Saudi Arabia); Nanostructured Materials and Nanotechnology Division, Central Metallurgical Research and Development Institute (CMRDI), P.O. Box: 87 Helwan, Cairo 11421 (Egypt); Ali, Atif M. [Department of Physics, Faculty of Science, King Khalid University, Abha (Saudi Arabia); Al-Sayari, S.A. [Promising Centre for Sensors and Electronic Devices (PCSED), Najran University, P.O. Box: 1988, Najran 11001 (Saudi Arabia); College of Science and Arts-Sharoura, Najran University (Saudi Arabia); Al-Hajry, A. [Department of Physics, College of Science and Arts, Najran University, P.O. Box 1988, Najran 11001 (Saudi Arabia); Promising Centre for Sensors and Electronic Devices (PCSED), Najran University, P.O. Box: 1988, Najran 11001 (Saudi Arabia)

    2016-09-11

    The photoluminescence (PL) and UV–vis spectral analysis of DAM-ADC (diallyl maleate: DAM, polyallyl diglycol carbonate: ADC) nuclear detector are demonstrated for the first time. The DAM-ADC surfaces were exposed to thin {sup 241}Am disk source that emits alpha particles with activity 333 kBq. It is found that the track density of the irradiated samples remarkably influences the PL characteristics of the DAM-ADC detector. The spectral peak heights and the integrated intensities under the peaks exhibit linear correlations with correlation coefficient R{sup 2}=0.9636 and 0.9806, respectively for different alpha particle fluences ranging from 8.16–40.82×10{sup 7} particles/cm{sup 2}. Additionally, a correlation coefficient R{sup 2}=0.9734 was achieved for the UV–vis spectral analysis. The linear fitting functions, along with the corresponding fitting parameters were evaluated in each case. Both the PL and the UV–vis data of the irradiated DAM-ADC samples showed considerable spectral differences, and hence they would be used to offer sensitive approaches for alpha particle detection.

  20. Nuclear and Particle Physics Simulations: The Consortium of Upper-Level Physics Software

    Science.gov (United States)

    Bigelow, Roberta; Moloney, Michael J.; Philpott, John; Rothberg, Joseph

    1995-06-01

    The Consortium for Upper Level Physics Software (CUPS) has developed a comprehensive series of Nine Book/Software packages that Wiley will publish in FY `95 and `96. CUPS is an international group of 27 physicists, all with extensive backgrounds in the research, teaching, and development of instructional software. The project is being supported by the National Science Foundation (PHY-9014548), and it has received other support from the IBM Corp., Apple Computer Corp., and George Mason University. The Simulations being developed are: Astrophysics, Classical Mechanics, Electricity & Magnetism, Modern Physics, Nuclear and Particle Physics, Quantum Mechanics, Solid State, Thermal and Statistical, and Wave and Optics.

  1. Perspectives on Entangled Nuclear Particle Pairs Generation and Manipulation in Quantum Communication and Cryptography Systems

    Directory of Open Access Journals (Sweden)

    Octavian Dănilă

    2012-01-01

    Full Text Available Entanglement between two quantum elements is a phenomenon which presents a broad application spectrum, being used largely in quantum cryptography schemes and in physical characterisation of the universe. Commonly known entangled states have been obtained with photons and electrons, but other quantum elements such as quarks, leptons, and neutrinos have shown their informational potential. In this paper, we present the perspective of exploiting the phenomenon of entanglement that appears in nuclear particle interactions as a resource for quantum key distribution protocols.

  2. Nuclear and particle physics with inverse compton γ-ray beam

    International Nuclear Information System (INIS)

    Fujiwara, Mamoru

    2004-01-01

    A new facility for GeV γ-ray beams in the energy range of 1.5 - 2.4 GeV is now used to develop hadron physics, and lead to an important finding of ''Penta-quark'' hadron, Θ + particle at 1540 MeV. The experimental results to observe φ and K + mesons guide us to a new look of quark dynamics with strangeness quarks. A beam line for MeV γ-rays is discussed in view of the observation of the parity violation due to the weak-strong coupling in nuclear medium. (author)

  3. The neutron a tool and an object in nuclear and particle physics

    CERN Document Server

    Börner, Hans G

    2012-01-01

    The reactor-based laboratory at the Institut Laue-Langevin is recognized as the world's most productive and reliable source of slow neutrons for the study of low energy particle and nuclear physics. The book highlightsthe impact of about 600 very diverse publications about work performedin these fields during the pastmore than 30 years of reactor operation at this institute.On one hand neutronsare used as a tool to generate nuclei in excited states for studying their structure and decay, in particular fission. Uniquely sensitive experiments can tell us a great deal about the symmetry character

  4. Nuclear propulsion systems for orbit transfer based on the particle bed reactor

    International Nuclear Information System (INIS)

    Powell, J.R.; Ludewig, H.; Horn, F.L.

    1987-01-01

    The technology of nuclear direct propulsion orbit transfer systems based on the Particle Bed Reactor (PBR) is described. A 200 megawatt illustrative design is presented for LEO to GEO and other high ΔV missions. The PBR-NOTV can be used in a one-way mode with the shuttle or an expendable launch vehicle, e.g., the Titan 34D7, or as a two-way reusable space tug. In the one-way mode, payload capacity is almost three times greater than that of chemical OTV's. PBR technology status is described and development needs outlined

  5. Nuclear size comparison of even titanium isotopes using 140-MeV α-particle scattering

    International Nuclear Information System (INIS)

    Roberson, P.L.; Goldberg, D.A.; Wall, N.S.; Woo, L.W.; Chen, H.L.

    1979-01-01

    Systematic variations in nuclear-matter distributions have been determined by analyzing the measured elastic scattering of 140-MeV alpha particles from /sup 46,48,50/Ti. The ''unique'' optical potentials obtained (J/sub R//4A approx. = 300 MeV fm 3 , J/sub I//4A approx. = 100 MeV fm 3 ) indicate that isotopic differences occur primarily in the strength of the imaginary potential. The rms matter radii increase with A, in contrast to those of the charge distributions. The matter-radius results are in agreement with Hartree-Fock calculations

  6. Mechanical behaviors of the dispersion nuclear fuel plates induced by fuel particle swelling and thermal effect II: Effects of variations of the fuel particle diameters

    International Nuclear Information System (INIS)

    Ding Shurong; Wang Qiming; Huo Yongzhong

    2010-01-01

    In order to predict the irradiation mechanical behaviors of plate-type dispersion nuclear fuel elements, the total burnup is divided into two stages: the initial stage and the increasing stage. At the initial stage, the thermal effects induced by the high temperature differences between the operation temperatures and the room temperature are mainly considered; and at the increasing stage, the intense mechanical interactions between the fuel particles and the matrix due to the irradiation swelling of fuel particles are focused on. The large-deformation thermo-elasto-plasticity finite element analysis is performed to evaluate the effects of particle diameters on the in-pile mechanical behaviors of fuel elements. The research results indicate that: (1) the maximum Mises stresses and equivalent plastic strains at the matrix increase with the fuel particle diameters; the effects of particle diameters on the maximum first principal stresses vary with burnup, and the considered case with the largest particle diameter holds the maximum values all along; (2) at the cladding near the interface between the fuel meat and the cladding, the Mises stresses and the first principal stresses undergo major changes with increasing burnup, and different variations exist for different particle diameter cases; (3) the maximum Mises stresses at the fuel particles rise with the particle diameters.

  7. An energy and direction independent fast neutron dosemeter based on electrochemically etched CR-39 nuclear track detectors

    International Nuclear Information System (INIS)

    James, K.; Matiullah; Durrani, S.A.

    1987-01-01

    A computer-based model is presented, which simulates the dose equivalent response of electrochemically etched CR-39 to fast neutrons of various energies and angles of incidence. Most previous calculations of the response of CR-39 have neglected the production of recoiling oxygen and carbon nuclei as well as α particles in the CR-39. We calculate that these 'heavy recoils' and α particles are the major source of electrochemically etchable tracks in bare CR-39 at neutron energies above approx. 2 MeV under typical etching conditions. Our calculations have been extended to predict the response of CR-39 used in conjunction with various combinations of polymeric front radiators and we have determined the radiator stack configuration with produces the most energy independent response. Again, the heavy recoils and α particles cannot be neglected and, for energies above approx. 2 MeV, these produce typically about 20% of the total response of our optimum stack. This type of fast neutron dosemeter is, however, strongly direction dependent. We have integrated the response over all appropriate angles to predict the dose equivalent response for two representative neutron fields, and we suggest a method for minimising the angular dependence. (author)

  8. The Role of Nuclear Fragmentation in Particle Therapy and Space Radiation Protection.

    Science.gov (United States)

    Zeitlin, Cary; La Tessa, Chiara

    2016-01-01

    The transport of the so-called HZE particles (those having high charge, Z, and energy, E) through matter is crucially important both in space radiation protection and in the clinical setting where heavy ions are used for cancer treatment. HZE particles are usually considered those having Z > 1, though sometimes Z > 2 is meant. Transport physics is governed by two types of interactions, electromagnetic (ionization energy loss) and nuclear. Models of transport, such as those used in treatment planning and space mission planning must account for both effects in detail. The theory of electromagnetic interactions is well developed, but nucleus-nucleus collisions are so complex that no fundamental physical theory currently describes them. Instead, interaction models are generally anchored to experimental data, which in some areas are far from complete. The lack of fundamental physics knowledge introduces uncertainties in the calculations of exposures and their associated risks. These uncertainties are greatly compounded by the much larger uncertainties in biological response to HZE particles. In this article, we discuss the role of nucleus-nucleus interactions in heavy charged particle therapy and in deep space, where astronauts will receive a chronic low dose from galactic cosmic rays (GCRs) and potentially higher short-term doses from sporadic, unpredictable solar energetic particles (SEPs). GCRs include HZE particles; SEPs typically do not and we, therefore, exclude them from consideration in this article. Nucleus-nucleus collisions can result in the breakup of heavy ions into lighter ions. In space, this is generally beneficial because dose and dose equivalent are, on the whole, reduced in the process. The GCRs can be considered a radiation field with a significant high-LET component; when they pass through matter, the high-LET component is attenuated, at the cost of a slight increase in the low-LET component. Not only are the standard measures of risk

  9. A novel tumor suppressor function of glycine N-methyltransferase is independent of its catalytic activity but requires nuclear localization.

    Directory of Open Access Journals (Sweden)

    Suchandra DebRoy

    Full Text Available Glycine N-methyltransferase (GNMT, an abundant cytosolic enzyme, catalyzes the transfer of a methyl group from S-adenosylmethionine (SAM to glycine generating S-adenosylhomocysteine and sarcosine (N-methylglycine. This reaction is regulated by 5-methyltetrahydrofolate, which inhibits the enzyme catalysis. In the present study, we observed that GNMT is strongly down regulated in human cancers and is undetectable in cancer cell lines while the transient expression of the protein in cancer cells induces apoptosis and results in the activation of ERK1/2 as an early pro-survival response. The antiproliferative effect of GNMT can be partially reversed by treatment with the pan-caspase inhibitor zVAD-fmk but not by supplementation with high folate or SAM. GNMT exerts the suppressor effect primarily in cells originated from malignant tumors: transformed cell line of non-cancer origin, HEK293, was insensitive to GNMT. Of note, high levels of GNMT, detected in regenerating liver and in NIH3T3 mouse fibroblasts, do not produce cytotoxic effects. Importantly, GNMT, a predominantly cytoplasmic protein, was translocated into nuclei upon transfection of cancer cells. The presence of GNMT in the nuclei was also observed in normal human tissues by immunohistochemical staining. We further demonstrated that the induction of apoptosis is associated with the GNMT nuclear localization but is independent of its catalytic activity or folate binding. GNMT targeted to nuclei, through the fusion with nuclear localization signal, still exerts strong antiproliferative effects while its restriction to cytoplasm, through the fusion with nuclear export signal, prevents these effects (in each case the protein was excluded from cytosol or nuclei, respectively. Overall, our study indicates that GNMT has a secondary function, as a regulator of cellular proliferation, which is independent of its catalytic role.

  10. Decommissioning of nuclear installations in the Russian Federation and newly independent states of the former USSR

    International Nuclear Information System (INIS)

    Kremnev, V.A.; Gavrilov, S.D.

    1993-01-01

    The results of NPP decommissioning in 1989 - 1992 have been summed up. Particular emphasis is laid on pre-decommissioning stage, the stage of all finally shutdown NPP units in CIS. Special attention is given to feasibility of WWER units, recycling of NPP metals and working out specifications for residual activity concentration content in NPP materials, thus making their unrestricted use possible, to the approaches to designing of bioshielding for the next generation NPP and to the choice of their structural materials. Fundamental and applied research conducted in the CIS over the last four years is reviewed and it is stressed that fundamental research can change the approach to the solution of the problem for different nuclear plants types. The recommendations based on the results of the investigations are given and the general directions for research and practical work including those conducted jointly with international community are outlined. (author). 27 refs, 1 fig., 3 tabs

  11. Research and systematization of 'hot' particles in the Semipalatinsk nuclear test site soils - methodology and first results

    International Nuclear Information System (INIS)

    Gorlachev, I.D.; Knyazev, B.B.; Kvochkina, T.N.; Lukashenko, S.N.

    2005-01-01

    Full text: Sources of soil activity in Semipalatinsk Nuclear Test Site (SNTS) could be both 'hot' particles dimensions from tens microns to units millimeters and sub-microns particles determining a matrix activity of soil samples. The fractionating of radionuclides and formation of 'hot' particles radionuclide composition arose from temperature changes and complicated nuclear-physical and thermodynamics processes occurring in a fire ball and cloud of nuclear explosion. Knowledge of 'hot' particles physical-chemical properties is needed for evaluation of radioactive products migration in the environment and danger level of the people external and internal exposure. Moreover, minute information about the structure and compound of 'radioactive' particles can be useful for specification of processes occurring in a fiery sphere when conducting explosions of different phylum and also for specification of radioactive fallout forming mechanism. The main polluted spots of SNTS could be divided into the four the species depending on nuclear explosion phylum. Species of radionuclide and their distribution for the different nuclear explosions are able to differ considerably. Therefore, several most typical areas for the each phylum test were selected and twenty soil samples were collected to reveal their radionuclide pollution peculiarities. Collected soil samples were separated into the five granulometric fractions: 1 mm - 2 mm, 0.5 mm - 1 mm. 0.28 mm-0.5 mm, 0.112 mm - 0.28 mm and 1 mm), 210 'hot' particles of second fraction (1>f>0.5 mm) and 154 'hot' particles of third fraction (0.5>f>0.28 mm) have been selection from the twelve SNTS soil samples by the compelled fission and visual identification methods. Main sources of soil samples and 'hot' particles activities are 239+240 Pu, 241 Am, 137 Cs and 152 Eu isotopes.In addition to the described works the special sampling of large 'hot' particles (dimension more than 2 mm) was carried out in areas of the ground and air tests

  12. Model-independent tracking of criticality signals in nuclear multifragmentation date

    International Nuclear Information System (INIS)

    Frankland, J.D.; Chbihi, A.

    2003-01-01

    We study multifragment production in central heavy-ion collisions using model-independent universal fluctuations theory and a wide range of INDRA data for central collisions of symmetric systems of total mass A: 75 - 400 at bombarding energies from 25 to 100 MeV/nucleon. We find evidence for two different regimes at low and high incident energies, respectively, defined by the fluctuation scaling properties of the largest fragment in each event, Z(max), which plays the role of an order parameter. Data for a wide range of system masses and incident energies collapse on to an approximately universal scaling function in each regime. The form of the scaling functions is established, and their dependence on total system mass and bombarding energy is mapped out. (authors)

  13. Model independent search for new particles in two-dimensional mass space using events with missing energy, two jets and two leptons with the CMS detector

    CERN Document Server

    AUTHOR|(CDS)2080070; Hebbeker, Thomas

    2017-07-07

    The discovery of a new particle consistent with the standard model Higgs boson at the Large Hadron Collider in 2012 completed the standard model of particle physics (SM). Despite its remarkable success many questions remain unexplained. Numerous theoretical models, predicting the existence of new heavy particles, provide answers to these unresolved questions and are tested at high energy experiments such as the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC). In this thesis a model independent search method for new particles in two-dimensional mass space in events with missing transverse energy is presented using 19.7 $\\mbox{fb}^{-1}$ of proton-proton collision data recorded by the CMS detector at a centre of mass energy $\\sqrt{s}$ = 8 TeV at the LHC. The analysis searches for signatures of pair-produced new heavy particles $\\mbox{T}^\\prime$ which decay further into unknown heavy particles $\\mbox{W}^\\prime$ and SM quarks $q$ ($\\mbox{T}^\\prime\\overline{\\mbox{T}^\\prime} \\rightarrow {...

  14. Nye County Nuclear Waste Repository Project Office independent scientific investigations program annual report, May 1997 - April 1998

    International Nuclear Information System (INIS)

    1998-07-01

    This annual summary report, prepared by the Nye County Nuclear Waste Repository Project Office (NWRPO), summarizes the activities that were performed during the period from May 1, 1997 to April 30, 1998. These activities were conducted in support of the Independent Scientific Investigation Program (ISIP) of Nye County at the Yucca Mountain Site (YMS). The Nye County NWRPO is responsible for protecting the health and safety of the Nye County residents. NWRPO's on-site representative is responsible for designing and implementing the Independent Scientific Investigation Program (ISIP). Major objectives of the ISIP include: Investigating key issues related to conceptual design and performance of the repository that can have major impact on human health, safety, and the environment; identifying areas not being addressed adequately by the Department of Energy (DOE). Nye County has identified several key scientific issues of concern that may affect repository design and performance which were not being adequately addressed by DOE. Nye County has been conducting its own independent study to evaluate the significance of these issues. This report summarizes the results of monitoring from two boreholes and the Exploratory Studies Facility (ESF) tunnel that have been instrumented by Nye County since March and April of 1995. The preliminary data and interpretations presented in this report do not constitute and should not be considered as the official position of Nye County. The ISIP presently includes borehole and tunnel instrumentation, monitoring, data analysis, and numerical modeling activities to address the concerns of Nye County

  15. Nye County nuclear waste repository project office independent scientific investigations program. Summary annual report, May 1996--April 1997

    International Nuclear Information System (INIS)

    1997-05-01

    This annual summary report, prepared by Multimedia Environmental Technology, Inc. (MET) on behalf of Nye County Nuclear Waste Project Office, summarizes the activities that were performed during the period from May 1, 1996 to April 30, 1997. These activities were conducted in support of the Independent Scientific Investigation Program (ISIP) of Nye County at the Yucca Mountain Site (YMS). The Nye County NWRPO is responsible for protecting the health and safety of the Nye County residents. NWRPO's on-site representative is responsible for designing and implementing the Independent Scientific Investigation Program (ISIP). Major objectives of the ISIP include: (1) Investigating key issues related to conceptual design and performance of the repository that can have major impact on human health, safety, and the environment. (2) Identifying areas not being addressed adequately by DOE Nye County has identified several key scientific issues of concern that may affect repository design and performance which were not being adequately addressed by DOE. Nye County has been conducting its own independent study to evaluate the significance of these issues

  16. Nye County Nuclear Waste Repository Project Office independent scientific investigations program annual report, May 1997--April 1998

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    This annual summary report, prepared by the Nye County Nuclear Waste Repository Project Office (NWRPO), summarizes the activities that were performed during the period from May 1, 1997 to April 30, 1998. These activities were conducted in support of the Independent Scientific Investigation Program (ISIP) of Nye County at the Yucca Mountain Site (YMS). The Nye County NWRPO is responsible for protecting the health and safety of the Nye County residents. NWRPO`s on-site representative is responsible for designing and implementing the Independent Scientific Investigation Program (ISIP). Major objectives of the ISIP include: Investigating key issues related to conceptual design and performance of the repository that can have major impact on human health, safety, and the environment; identifying areas not being addressed adequately by the Department of Energy (DOE). Nye County has identified several key scientific issues of concern that may affect repository design and performance which were not being adequately addressed by DOE. Nye County has been conducting its own independent study to evaluate the significance of these issues. This report summarizes the results of monitoring from two boreholes and the Exploratory Studies Facility (ESF) tunnel that have been instrumented by Nye County since March and April of 1995. The preliminary data and interpretations presented in this report do not constitute and should not be considered as the official position of Nye County. The ISIP presently includes borehole and tunnel instrumentation, monitoring, data analysis, and numerical modeling activities to address the concerns of Nye County.

  17. Nuclear densities of 1fsub(7/2) nuclei from elastic alpha-particle scattering

    International Nuclear Information System (INIS)

    Friedman, E.; Gils, H.J.; Rebel, H.

    1983-12-01

    The elastic scattering of 104 MeV α particles by sup(40,42,43,44,48)Ca, 50 Ti, 51 V, 52 Cr has been analyzed by phenomenological and semimicroscopic optical potentials in order to get information on isotopic and isotonic differences of the α particle optical potentials and of nuclear matter densities. The phenomenological optical potentials based on a Fourier-Bessel description of the real part reveal different behaviour in size and shape for the isotonic chain as compared to the isotopic chain. Odd-even effects are also indicated to be different for isotones and isotopes. The semi-microscopic analyses use a single-folding model with a density-dependent effective αN-interaction including a realistic local density approximation. The calculated potentials are fully consistent with the phenomenological ones. Isopotic and isotonic differences of the nuclear matter densities obtained from the folding model in general show a similar behavior as the optical potential differences. The results on matter densities are compared to other investigations. (orig.) [de

  18. Porous chromatographic materials as substrates for preparing synthetic nuclear explosion debris particles

    International Nuclear Information System (INIS)

    Harvey, S.D.; Carman, A.J.; Martin Liezers; Antolick, K.C.; Garcia, B.J.; Eiden, G.C.; Sweet, L.E.

    2013-01-01

    Several porous chromatographic materials were investigated as synthetic substrates for preparing surrogate nuclear explosion debris particles. Eighteen metals, including some of forensic interest, were loaded onto materials by immersing them in metal solutions (556 mg/L of each metal) to fill the pores, applying gentle heat (110 deg C) to drive off water, and then treating them at high temperatures (up to 800 deg C) in air to form less soluble metal species. High-boiling-point metals were uniformly loaded on spherical controlled-pore glass to emulate early fallout, whereas low-boiling-point metals were loaded on core-shell silica to represent coated particles formed later in the nuclear fallout-formation process. Analytical studies characterized material balance and the formation of recalcitrant species. Metal loading was 1.5-3 times higher than expected from the pore volume alone, a result attributed to surface coating. Most metals were passively loaded; that is, solutions filled the pores without active metal discrimination. However, niobium and tin concentrations were lower in solutions after pore filling, and were found in elevated concentrations in the final products, indicating selective loading. High-temperature treatments caused reduced solubility of several metals, and the loss of some volatile species (rhenium and tellurium). Sample preparation reproducibility was high (the inter- and intra-batch relative standard deviations were 7.8 and 0.84 %, respectively) indicating suitability for use as a working standard for analytical methods development. We anticipate future standardized radionuclide-loaded materials will find use in radioanalytical methods development and/or serve as a starting material for the synthesis of more complex nuclear explosion debris forms (e.g., Trinitite). (author)

  19. Localisation and identification of radioactive particles in solid samples by means of a nuclear track technique

    International Nuclear Information System (INIS)

    Boehnke, Antje; Treutler, Hanns-Christian; Freyer, Klaus; Schubert, Michael; Holger Weiss

    2005-01-01

    This study is aimed to develop a generally applicable methodology of investigation that can be used for the localisation of single alpha-active particles in solid samples, such as industrial dust or natural soils, sediments and rocks by autoradiography using solid-state nuclear track detectors. The developed technique allows the detection of local enrichments of alpha-emitters in any solid material. The results of such an investigation are of interest from technical, biological and environmental points of view. The idea behind the methodology is to locate the position of alpha-active spots in a sample by attaching the track detector to the sample in a defined manner, thoroughly described in the paper. The located alpha-active particles are subsequently analysed by an electron microscope and an electron microprobe. An example of the application of this methodology is also given. An ultra-fine -grained ore-processing residue, which causes serious environmental pollution in the respective mining district and thus limits possible land use and affects quality of life in the area, was examined using the described technique. The investigation revealed considerable amounts of alpha-active particles in this material

  20. The single-particle potential of nuclear matter in the LOCV framework

    Energy Technology Data Exchange (ETDEWEB)

    Modarres, M., E-mail: mmodares@ut.ac.ir [Physics Department, University of Tehran, North-Kargar Ave., 1439955961 Tehran (Iran, Islamic Republic of); Rajabi, A. [Physics Department, Shahid Rajaei Teacher Training University, Lavizan, 16788 Tehran (Iran, Islamic Republic of)

    2011-10-01

    The density and momentum dependence of single-particle potential (SPP) and effective mass of symmetric nuclear matter are studied in the framework of lowest order constrained variational (LOCV) method. The Reid68, the Reid68-{Delta} and the Av{sub 18} interactions are considered as the input nucleon-nucleon potentials. It is shown that the SPP of nuclear matter, at fixed density, is an increasing function of nucleon momentum, and it has different behavior for the Reid type potentials with respect to Av{sub 18} interaction. We find good agreements between our LOCV SPP and those coming from others many-body techniques such as the (Dirac-)Brueckner-Hartree-Foch ((D)BHF), the fermion hypernetted chain (FHNC), mean field (MF), etc. On the other hand SPP dramatically depends on the density at low and high nucleon momentums. While the effective mass of nuclear matter increases as we increase the nucleon momentum, it decreases at the Fermi surface. Again, good agreements are observed between our calculated effective mass and those coming from the methods mentioned above.

  1. (μ-,e-) conversion: a symbiosis of particle and nuclear physics

    International Nuclear Information System (INIS)

    Kosmas, T.S.; Vergados, J.D.

    1996-01-01

    (μ - ,e - ) conversion is the experimentally most interesting lepton flavor violating process. From a theoretical point of view it is an interesting interplay of particle and nuclear physics. The effective transition operator, depending on the gauge model, is in general described in terms of a combination of four terms (isoscalar and isovector, Fermi-like as well as axial vector-like). The experimentally most interesting ground state to ground state transition is adequately described in terms of the usual proton and neutron form factors. These were computed in both the shell model and RPA. Since it is of interest to know the portion of the strength exhausted by the coherent (ground state to ground state) transition, the total transition rate to all final states must also be computed. This was done (i) in RPA by explicitly summing over all final states (ii) in the context of the closure approximation (using shell model and RPA for constructing the initial state), and (iii) in the context of nuclear matter mapped into nuclei via a local density approximation.We found that, apart from small local oscillations, the conversion rate keeps increasing from light to heavy nuclear elements. We also find that the coherent mode is dominant (it exhausts more than 90% of the sum rule). Various gauge models are discussed. In general the predicted branching ratio is much smaller compared to the present experimental limit. (orig.)

  2. Metallic nickel nano- and fine particles induce JB6 cell apoptosis through a caspase-8/AIF mediated cytochrome c-independent pathway

    Directory of Open Access Journals (Sweden)

    Castranova Vincent

    2009-04-01

    induced by metallic nickel particles in JB6 cells is through a caspase-8/AIF mediated cytochrome c-independent pathway. Lamin A and beta-actin are involved in the process of apoptosis. Activation of Akt and Bcl-2 may play an important role in preventing cytochrome c release from mitochondria to the cytoplasm and may also be important in the carcinogenicity of metallic nickel particles. In addition, the results may be useful as an important reference when comparing the toxicities of different nickel compounds.

  3. Experimental studies of particle acceleration with ultra-intense lasers - Applications to nuclear physics experiments involving laser-produced plasmas

    International Nuclear Information System (INIS)

    Plaisir, C.

    2010-11-01

    For the last ten years, the Ultra High Intensity Lasers offer the opportunity to produce accelerated particle beams which contain more than 10 12 electrons, protons accelerated into a few ps. We have simulated and developed some diagnostics based on nuclear activation to characterize both the angular and the energy distributions of the particle beams produced with intense lasers. The characterization methods which are presented are illustrated by means of results obtained in different experiments. We would use the particle beams produced to excite nuclear state in a plasma environment. It can modify intrinsic characteristics of the nuclei such as the half-life of some isomeric states. To prepare this kind of experiments, we have measured the nuclear reaction cross section (gamma,n) to produce the isomeric state of the 84 Rb, which has an excitation energy of 463 keV, with the electron accelerator ELSA of CEA/DIF in Bruyeres-le-Chatel (France). (author)

  4. Production and characterization of monodisperse uranium particles for nuclear safeguards applications

    Energy Technology Data Exchange (ETDEWEB)

    Knott, Alexander

    2016-07-01

    Environmental sampling is a very effective measure to detect undeclared nuclear activities. Generally, samples are taken as swipe samples on cotton. These swipes contain minute quantities of particulates which have an inherent signature of their production and release scenario. These inspection samples are assessed for their morphology, elemental composition and their isotopic vectors. Mass spectrometry plays a crucial role in determining the isotopic ratios of uranium. Method validation and instrument calibration with well-characterized quality control (QC)-materials, reference materials (RMs) and certified reference materials (CRMs) ensures reliable data output. Currently, the availability of suitable well defined microparticles containing uranium and plutonium reference materials is very limited. Primarily, metals, oxides and various uranium and plutonium containing solutions are commercially available. Therefore, the IAEA's Safeguards Analytical Services (SGAS) cooperates with the Institute of Nuclear Waste Management and Reactor Safety (IEK-6) at the Forschungszentrum Juelich GmbH in a joint task entitled ''Production of Particle Reference Materials''. The work presented in this thesis has been partially funded by the IAEA, Forschungszentrum Juelich GmbH and the Federal Ministry of Economic Affairs and Energy (BMWi) through the ''Joint Program on the Technical Development and Further Improvement of IAEA Safeguards between the Government of the Federal Republic of Germany and the IAEA''. The first step towards monodisperse microparticles was the development of pure uranium oxide particles made from certified reference materials. The focus of the dissertation is (1) the implementation of a working setup to produce monodisperse uranium oxide particles and (2) the characterization of these particles towards the application as QC-material. Monodisperse uranium oxide particles were produced by spray pyrolysis. It was

  5. Ciglitazone induces caspase-independent apoptosis via p38-dependent AIF nuclear translocation in renal epithelial cells

    International Nuclear Information System (INIS)

    Kwon, Chae Hwa; Yoon, Chang Soo; Kim, Yong Keun

    2008-01-01

    Peroxisome proliferator-activated receptor γ (PPARγ) agonists have been reported to induce apoptosis in a variety of cell types including renal proximal epithelial cells. However, the underlying mechanism of cell death induced by PPARγ agonists has not been clearly defined in renal proximal tubular cells. This study was therefore undertaken to determine the mechanism by which ciglitazone, a synthetic PPARγ agonist, induces apoptosis in opossum kidney (OK) cells, an established renal epithelial cell line. Ciglitazone treatment induced apoptotic cell death in a dose- and time-dependent manner. Ciglitazone caused a transient activation of ERK and sustained activation of p38 MAP kinase. Ciglitazone-mediated cell death was attenuated by the p38 inhibitor SB203580 and transfection of dominant-negative form of p38, but not by the MEK inhibitor U0126, indicating that p38 MAP kinase activation is involved in the ciglitazone-induced cell death. Although ciglitazone-induced caspase-3 activation, the ciglitazone-mediated cell death was not affected by the caspase-3 inhibitor DEVD-CHO. Ciglitazone-induced mitochondrial membrane depolarization and apoptosis-inducing factor (AIF) nuclear translocation and these effects were prevented by the p38 inhibitor. These results suggest that ciglitazone induces caspase-independent apoptosis through p38 MAP kinase-dependent AIF nuclear translocation in OK renal epithelial cells

  6. Fukushima: the Japanese report in French - 'Official report of the independent inquiry Commission on the nuclear accident in Fukushima'

    International Nuclear Information System (INIS)

    Huet, Sylvestre; Ash, Robert; Gilles, D.; Fargette, Guy; Fetet, Pierre; Girard, Odile; Payrault-Gaber, Marie-France; Royer, Jean-Marc; Thirion, Catherine

    2012-11-01

    In its first part, this report describes the (Japanese) Inquiry Commission's mandate, its expectations, what it did, what it did not do, and then describes the accident, gives a chronology of events after the earthquake and the tsunami occurred, and states and comments the following conclusions: a catastrophe with a human origin, earthquake-induced damages, an assessment of operational problems, problems met during emergency intervention, evacuation problems, unresolved public health and welfare problems, need to reform the regulators as well as the operator, laws and rules. Seven recommendations are proposed; they address the control of the nuclear regulation body, the reform of the crisis management system, the government responsibility for public health and welfare, the control of operators, criteria for a new regulator, a reform of laws related to nuclear energy, and the implementation of a system of independent inquiry commissions. Then the report comments and discusses in detail the results of the inquiry which first tried to assess whether the accident was avoidable, and studied various elements: the accident, the emergency response, the damage extent, the organisational problems in the prevention of the accident, the legal system. Results of inquiries on evacuated people and on personnel are given in appendix, as well as the content of all the Commission meetings

  7. Independent control of metal cluster and ceramic particle characteristics during one-step synthesis of Pt/TiO2

    DEFF Research Database (Denmark)

    Schulz, H.; Madler, L.; Strobel, R.

    2005-01-01

    Rapid quenching during flame spray synthesis of Pt/TiO2 (0-10 Wt% Pt) is demonstrated as a versatile method for independent control of support (TiO2) and noble metal (Pt)cluster characteristics. Titania grain size, morphology, crystal phase structure, and crystal size were analyzed by nitrogen ad...

  8. Summary report of consultants' meeting on nuclear data of charged-particle interactions for medical therapy applications

    International Nuclear Information System (INIS)

    Capote Noy, R.; Vatnitskiy, S.

    2007-01-01

    A summary is given of a Consultants' Meeting assembled to assess the viability of a new IAEA Co-ordinated Research Project (CRP) on Charged-Particle Interaction Data for Radiotherapy. The need for a programme to compile and evaluate charged-particle nuclear data for therapeutic applications was strongly agreed. Both the technical discussions and the expected outcomes of such a project are described, along with detailed recommendations for implementation. The meeting was jointly organized by NAPC/Nuclear Data Section and NAHU/Dosimetry and Medical Radiation Physics Section. (author)

  9. Pure spin-3/2 propagator for use in particle and nuclear physics

    Science.gov (United States)

    Kristiano, J.; Clymton, S.; Mart, T.

    2017-11-01

    We propose the use of a pure spin-3/2 propagator in the (3 /2 ,0 )⊕(0 ,3 /2 ) representation in particle and nuclear physics. To formulate the propagator in a covariant form we use the antisymmetric tensor spinor representation and we consider the Δ resonance contribution to the elastic π N scattering as an example. We find that the use of a conventional gauge-invariant interaction Lagrangian leads to a problem: the obtained scattering amplitude does not exhibit the resonance behavior. To overcome this problem we modify the interaction by adding a momentum dependence. As in the case of the Rarita-Schwinger formalism, we find that a perfect resonance description could be obtained in the pure spin-3/2 formulation only if hadronic form factors were considered in the interactions.

  10. Characteristics of particle production in high energy nuclear collisions a model-based analysis

    CERN Document Server

    Guptaroy, P; Bhattacharya, S; Bhattacharya, D P

    2002-01-01

    The present work pertains to the production of some very important negatively charged secondaries in lead-lead and gold-gold collisions at AGS, SPS and RHIC energies. We would like to examine here the role of the particular version of sequential chain model (SCM), which was applied widely in the past in analysing data on various high-energy hadronic collisions, in explaining now the latest findings on the features of particle production in the relativistic nucleus-nucleus collisions. The agreement between the model of our choice and the measured data is found to be modestly satisfactory in cases of the most prominent and abundantly produced varieties of the secondaries in the above-stated two nuclear collisions. (25 refs).

  11. Theory of nuclear reactions with participation of slow charged particles in solids

    International Nuclear Information System (INIS)

    Barts, B.I.; Barts, D.B.; Grinenko, A.A.

    1992-01-01

    In the last two years, there has been a sharp increase of interest in various aspects of the interaction of nuclear particles in solids. This is due, above all, to the sensational reports of the possibility that deuteron fusion reactions take place at normal temperatures. At the present time, it is clear that, among the various factors, an important role for the understanding of this remarkable phenomenon is played by crystal fields that significantly change the tail of the Coulomb barrier and, thus, its penetrability. Here, in connection with the problem of the cold fusion of deuterons, an analysis is made of the influence of screening of the deuteron charges by electrons of the crystal on the penetrability of the Coulomb barrier. A study is made of the reaction-enhancement method in the case when the deuterons move in the general crystal potential well near one of the minima of the crystal potential

  12. γ-Particle coincidence technique for the study of nuclear reactions

    Science.gov (United States)

    Zagatto, V. A. B.; Oliveira, J. R. B.; Allegro, P. R. P.; Chamon, L. C.; Cybulska, E. W.; Medina, N. H.; Ribas, R. V.; Seale, W. A.; Silva, C. P.; Gasques, L. R.; Zahn, G. S.; Genezini, F. A.; Shorto, J. M. B.; Lubian, J.; Linares, R.; Toufen, D. L.; Silveira, M. A. G.; Rossi, E. S.; Nobre, G. P.

    2014-06-01

    The Saci-Perere γ ray spectrometer (located at the Pelletron AcceleratorLaboratory - IFUSP) was employed to implement the γ-particle coincidence technique for the study of nuclear reaction mechanisms. For this, the 18O+110Pd reaction has been studied in the beam energy range of 45-54 MeV. Several corrections to the data due to various effects (energy and angle integrations, beam spot size, γ detector finite size and the vacuum de-alignment) are small and well controlled. The aim of this work was to establish a proper method to analyze the data and identify the reaction mechanisms involved. To achieve this goal the inelastic scattering to the first excited state of 110Pd has been extracted and compared to coupled channel calculations using the São Paulo Potential (PSP), being reasonably well described by it.

  13. γ-Particle coincidence technique for the study of nuclear reactions

    Energy Technology Data Exchange (ETDEWEB)

    Zagatto, V.A.B., E-mail: vinicius.zagatto@gmail.com [Instituto de Física da Universidade de São Paulo (Brazil); Oliveira, J.R.B.; Allegro, P.R.P.; Chamon, L.C.; Cybulska, E.W.; Medina, N.H.; Ribas, R.V.; Seale, W.A.; Silva, C.P.; Gasques, L.R. [Instituto de Física da Universidade de São Paulo (Brazil); Zahn, G.S.; Genezini, F.A.; Shorto, J.M.B. [Instituto de Pesquisas Energéticas e Nucleares (Brazil); Lubian, J.; Linares, R. [Instituto de Física da Universidade Federal Fluminense (Brazil); Toufen, D.L. [Instituto Federal de Educação, Ciência e Tecnologia (Brazil); Silveira, M.A.G. [Centro Universitário da FEI (Brazil); Rossi, E.S. [Centro Universitário FIEO – UNIFIEO (Brazil); Nobre, G.P. [Lawrence Livermore National Laboratory (United States)

    2014-06-01

    The Saci-Perere γ ray spectrometer (located at the Pelletron AcceleratorLaboratory – IFUSP) was employed to implement the γ-particle coincidence technique for the study of nuclear reaction mechanisms. For this, the {sup 18}O+{sup 110}Pd reaction has been studied in the beam energy range of 45–54 MeV. Several corrections to the data due to various effects (energy and angle integrations, beam spot size, γ detector finite size and the vacuum de-alignment) are small and well controlled. The aim of this work was to establish a proper method to analyze the data and identify the reaction mechanisms involved. To achieve this goal the inelastic scattering to the first excited state of {sup 110}Pd has been extracted and compared to coupled channel calculations using the São Paulo Potential (PSP), being reasonably well described by it.

  14. The particle swarm optimization algorithm applied to nuclear systems surveillance test planning

    International Nuclear Information System (INIS)

    Siqueira, Newton Norat

    2006-12-01

    This work shows a new approach to solve availability maximization problems in electromechanical systems, under periodic preventive scheduled tests. This approach uses a new Optimization tool called PSO developed by Kennedy and Eberhart (2001), Particle Swarm Optimization, integrated with probabilistic safety analysis model. Two maintenance optimization problems are solved by the proposed technique, the first one is a hypothetical electromechanical configuration and the second one is a real case from a nuclear power plant (Emergency Diesel Generators). For both problem PSO is compared to a genetic algorithm (GA). In the experiments made, PSO was able to obtain results comparable or even slightly better than those obtained b GA. Therefore, the PSO algorithm is simpler and its convergence is faster, indicating that PSO is a good alternative for solving such kind of problems. (author)

  15. A unique nuclear thermal rocket engine using a particle bed reactor

    Science.gov (United States)

    Culver, Donald W.; Dahl, Wayne B.; McIlwain, Melvin C.

    1992-01-01

    Aerojet Propulsion Division (APD) studied 75-klb thrust Nuclear Thermal Rocket Engines (NTRE) with particle bed reactors (PBR) for application to NASA's manned Mars mission and prepared a conceptual design description of a unique engine that best satisfied mission-defined propulsion requirements and customer criteria. This paper describes the selection of a sprint-type Mars transfer mission and its impact on propulsion system design and operation. It shows how our NTRE concept was developed from this information. The resulting, unusual engine design is short, lightweight, and capable of high specific impulse operation, all factors that decrease Earth to orbit launch costs. Many unusual features of the NTRE are discussed, including nozzle area ratio variation and nozzle closure for closed loop after cooling. Mission performance calculations reveal that other well known engine options do not support this mission.

  16. Diagnostics of Nuclear Reactor Accidents Based on Particle Swarm Optimization Trained Neural Networks

    International Nuclear Information System (INIS)

    Abdel-Aal, M.M.Z.

    2004-01-01

    Automation in large, complex systems such as chemical plants, electrical power generation, aerospace and nuclear plants has been steadily increasing in the recent past. automated diagnosis and control forms a necessary part of these systems,this contains thousands of alarms processing in every component, subsystem and system. so the accurate and speed of diagnosis of faults is an important factors in operation and maintaining their health and continued operation and in reducing of repair and recovery time. using of artificial intelligence facilitates the alarm classifications and faults diagnosis to control any abnormal events during the operation cycle of the plant. thesis work uses the artificial neural network as a powerful classification tool. the work basically is has two components, the first is to effectively train the neural network using particle swarm optimization, which non-derivative based technique. to achieve proper training of the neural network to fault classification problem and comparing this technique to already existing techniques

  17. Particle swarm optimization applied to data reconciliation in nuclear power plant

    International Nuclear Information System (INIS)

    Valdetaro, Eduardo Damianik; Schirru, Roberto

    2009-01-01

    Mass and energy balance are important issues that needs to keep into account in nuclear power plants. Data Reconciliation and Parameter Estimation (DRPE) and gross errors detection are techniques of increasing interest. Works using Genetic Algorithm (GA) have been successfully used in the Data Reconciliation (DR) nonlinear optimization problem, and it seems that evolutionary algorithms performs well without the complex calculations used by the conventional methods. The aim of this paper is to present the Particle Swarm Optimization Algorithm (PSO) as an alternative to the use of modified GA, which was applied to data reconciliation with simultaneous gross errors detection. In this paper, the DR formulation uses a redescending estimator as objective function and simulation results show that PSO applied to DRPE problem is faster than modified GA presented in literature, do not involve complex calculations and do not need complex parameters to adjust. The PSO algorithm is also able to handle the non-differentiable characteristics of the redescending estimator. (author)

  18. Cross section measurement of alpha particle induced nuclear reactions on natural cadmium up to 52 MeV

    OpenAIRE

    Ditrói, F.; Takács, S.; Haba, H.; Komori, Y.; Aikawa, M.

    2016-01-01

    Cross sections of alpha particle induced nuclear reactions have been measured on thin natural cadmium targets foils in the energy range from 11 to 51.2 MeV. This work was a part of our systematic study on excitation functions of light ion induced nuclear reactions on different target materials. Regarding the cross sections, the alpha induced reactions are not deeply enough investigated. Some of the produced isotopes are of medical interest, others have application in research and industry. Th...

  19. The role of colloids and suspended particles in radionuclide transport in the Canadian concept for nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Vilks, P.

    1994-02-01

    AECL Research is developing a concept for the permanent disposal of nuclear fuel waste in a deep engineered vault in plutonic rock of the Canadian Shield and is preparing an Environmental Impact Statement (EIS) to document its case for the acceptability of the disposal concept. This report, one in a series of supporting documents for the EIS, addresses the role of particles in radionuclide transport. It summarizes our studies of natural particles in groundwater and presents the arguments used to justify the omission of particle-facilitated transport in the geosphere model that is based on the Whiteshell Research Area (WRA) and used in the postclosure assessment study case. Because radiocolloids formed in the vault will not be able to migrate through the clay buffer, radiocolloid formation in the geosphere will be determined by the sorption of radionuclides onto particles in groundwater. These particles consist of typical fracture-lining minerals, such as clays, micas and quartz; precipitated particles, such as colloidal silica and Fe-Si oxyhydroxides; and organic particles. In groundwater from the WRA, the average concentrations of colloids and suspended particles are 0.34 and 1.4 mg/L respectively. Particle-facilitated transport is not included in the geosphere model because the concentrations of particles in groundwater from the WRA are too low to have a significant impact on radionuclide transport. (author). 92 refs., 11 tabs., 13 figs

  20. The Role of Nuclear Fragmentation in Particle Therapy and Space Radiation Protection

    Directory of Open Access Journals (Sweden)

    Cary eZeitlin

    2016-03-01

    Full Text Available The transport of so-called HZE particles (those having high charge, Z, and energy, E through matter is crucially important both in space radiation protection and in the clinical setting where heavy ions are used for cancer treatment. Transport physics is governed by two types of interactions, electromagnetic (ionization energy loss and nuclear. Models of transport such as those used in treatment planning and space mission planning must account for both effects in detail. The theory of electromagnetic interactions is well developed, but nucleus-nucleus collisions are so complex that no fundamental physical theory currently describes them. Instead, interaction models are generally anchored to experimental data, which in some areas are far from complete. The lack of fundamental physics knowledge introduces uncertainties in the calculations of exposures and their associated risks. These uncertainties are greatly compounded by the much larger uncertainties in biological response to HZE particles. In this article, we discuss the role of nucleus-nucleus interactions in heavy charged particle therapy and in deep space, where astronauts will receive a chronic low dose from Galactic Cosmic Rays (GCRs and potentially higher short-term doses from sporadic, unpredictable Solar Energetic Particles (SEPs. GCRs include HZE particles; SEPs typically do not and we therefore exclude them from consideration in this article. Nucleus-nucleus collisions can result in the breakup of heavy ions into lighter ions. In space, this is generally beneficial because dose and dose equivalent are, on the whole, reduced in the process. The GCRs can be considered a radiation field with a significant high-LET component; when they pass through matter, the high-LET component is attenuated, at the cost of a slight increase in the low-LET component. Not only are the standard measures of risk reduced by fragmentation, but it can be argued that fragmentation also reduces the

  1. Summary of particle bed reactor designs for the Space Nuclear Thermal Propulsion Program

    Science.gov (United States)

    Powell, J. R.; Ludewig, H.; Todosow, M.

    1993-09-01

    A summary report of the Particle Bed Reactor (PBR) designs considered for the space nuclear thermal propulsion program has been prepared. The first chapters outline the methods of analysis, and their validation. Monte Carlo methods are used for the physics analysis, several new algorithms are used for the fluid dynamics heat transfer and engine system analysis, and commercially available codes are used for the stress analysis. A critical experiment, prototypic of the PBR was used for the physics validation, and blowdown experiments using fuel beds of prototypic dimensions were used to validate the power extraction capabilities from particle beds. In all four different PBR rocket reactor designs were studied to varying degrees of detail. They varied in power from 400 MW to 2000 MW. These designs were all characterized by a negative prompt coefficient, due to Doppler feedback, and the feedback due to moderator heat up varied from slightly negative to slightly positive. In all practical cases, the coolant worth was positive, although core configurations with negative coolant worth could be designed. In all practical cases the thrust/weight ratio was greater than 20.

  2. Development of automatic nuclear emulsion plate analysis system and its application to elementary particle reactions, 2

    International Nuclear Information System (INIS)

    Ushida, Noriyuki; Otani, Masashi; Kumazaki, Noriyasu

    1984-01-01

    This system is composed of precise coordinate measuring apparatuses, a stage controller and various peripherals, employing NOVA 4/C as the host computer. The analyzed results are given as the output to a printer or an XY plotter. The data required for experiment, sent from Nagoya University and others, are received by the host computer through an acoustic coupler, and stored in floppy disks. This paper contains simple explanation on the monitor for the events which occur immediately after the on-line measurement ''MTF 1'', the XY plotter and the acoustic coupler, which hold important position in the system in spite of low cost, due to the development of useful program, as those were not described in the previous paper. The three-dimensional reconstruction of tracks and various errors, corrective processing and analytical processing after corrective processing as off-line processing are also described. In addition, the application of the system was made to the E-531 neutrino experiment in Fermi National Accelerator Laboratory, which attempted to measure the life of the charm particles generated in neutrino reaction with a composite equipment composed of nuclear plates and various counters. First, the outline of the equipment, next, the location of neutrino reaction and the surveillance of charm particle decay using MTF program as the analyzing method at the target, and thirdly, the emulsion-counter data fitting are explained, respectively. (Wakatsuki, Y.)

  3. Workshop on nuclear chromodynamics: Quarks and gluons in particles and nuclei

    International Nuclear Information System (INIS)

    Brodsky, S.; Moniz, E.

    1985-01-01

    The assertion that quantum chromodynamics (QCD) is the correct theory describing strong interaction phenomena has, largely by repetition, become rather non-controversial. It is likely even true. However, whether or not it is correct in detail, the experimentally supported realization that colored quarks and gluons are the elementary degrees of freedom, that asymptotic freedom makes short distance phenomena rather ''simple'' to understand, and that color is confined on the hadronic length scale of -- 1 fm has led to a profound change in the character of our attempts to understand the structure and interactions of both hadrons and nuclei. Many of the most important issued in particle physics and in nuclear physics are now seen to be intimately connected. An understanding of the validity and limits of effective theories based upon hadron degrees of freedom, so phenomenologically successful in describing a host of low energy phenomena, is coming into focus. The existence of new forms of matter grounded in the hidden color degree of freedom is predicted. These considerations form the subject of nuclear chromodynamics (NCD). The subject is far from mature and is developing rapidly

  4. Caspase-independent cell death mediated by apoptosis-inducing factor (AIF) nuclear translocation is involved in ionizing radiation induced HepG2 cell death

    International Nuclear Information System (INIS)

    Sun, Hengwen; Yang, Shana; Li, Jianhua; Zhang, Yajie; Gao, Dongsheng; Zhao, Shenting

    2016-01-01

    Hepatocellular carcinoma (HCC) is the fifth most common cancer in the world. The aim of radiotherapy is to eradicate cancer cells with ionizing radiation. Except for the caspase-dependent mechanism, several lines of evidence demonstrated that caspase-independent mechanism is directly involved in the cell death responding to irradiation. For this reason, defining the contribution of caspase-independent molecular mechanisms represents the main goal in radiotherapy. In this study, we focused on the role of apoptosis-inducing factor (AIF), the caspase-independent molecular, in ionizing radiation induced hepatocellular carcinoma cell line (HepG2) cell death. We found that ionizing radiation has no function on AIF expression in HepG2 cells, but could induce AIF release from the mitochondria and translocate into nuclei. Inhibition of AIF could reduce ionizing radiation induced HepG2 cell death. These studies strongly support a direct relationship between AIF nuclear translocation and radiation induced cell death. What's more, AIF nuclear translocation is caspase-independent manner, but not caspase-dependent manner, in this process. These new findings add a further attractive point of investigation to better define the complex interplay between caspase-independent cell death and radiation therapy. - Highlights: • AIF nuclear translocation is involved in ionizing radiation induced hepatocellular carcinoma cell line HepG2 cell death. • AIF mediated cell death induced by ionizing radiation is caspase-independent. • Caspase-independent pathway is involved in ionzing radiation induced HepG2 cell death.

  5. Associated-particle sealed-tube neutron probe: Detection of explosives, contraband, and nuclear materials

    International Nuclear Information System (INIS)

    Rhodes, E.; Dickerman, C.E.

    1996-01-01

    Continued research and development of the APSTNG shows the potential for practical field use of this technology for detection of explosives, contraband, and nuclear materials. The APSTNG (associated-particle sealed-tube generator) inspects the item to be examined using penetrating 14-MeV neutrons generated by the deuterium-tritium reaction inside a compact accelerator tube. An alpha detector built into the sealed tube detects the alpha-particle associated with each neutron emitted in a cone encompassing the volume to be inspected. Penetrating high-energy gamma-rays from the resulting neutron reactions identify specific nuclides inside the volume. Flight-times determined from the detection times of gamma-rays and alpha-particles separate the prompt and delayed gamma-ray spectra and allow a coarse 3-D image to be obtained of nuclides identified in the prompt spectrum. The generator and detectors can be on the same side of the inspected object, on opposite sides, or with intermediate orientations. Thus, spaces behind walls and other confined regions can be inspected. Signals from container walls can be discriminated against using the flight-time technique. No collimators or shielding are required, the neutron generator is relatively small, and commercial-grade electronics are employed. The use of 14-MeV neutrons yields a much higher cross-section for detecting nitrogen than that for systems based on thermal-neutron reactions alone, and the broad range of elements with significant 14-MeV neutron cross-sections extends explosives detection to other elements including low-nitrogen compounds, and allows detection of many other substances. Proof-of-concept experiments have been successfully performed for conventional explosives, chemical warfare agents, cocaine, and fissionable materials

  6. Nuclear and particle physics applications of the Bohm picture of quantum mechanics

    International Nuclear Information System (INIS)

    Miranda, A

    2009-01-01

    Aproximation methods for calculating individual particle/field motions in spacetime at the quantum level of accuracy (a key feature of the Bohm picture (BP) of quantum mechanics) are studied. This sharply illuminates not only the deep quantum structures underlying any observable quantum statistical laws of motion of particles and fields in spacetime, but also how the continuous merging of the so-called classical and quantal modes of description actually occurs, with no breaks anywhere. Modern textbook presentations of Quantum Theory are used throughout, but only to provide the necessary, already existing, tested formalisms and calculational techniques. New coherent insights, reinterpretations of old solutions and results, and new (in principle testable) quantitative and qualitative predictions can be obtained on the basis of the BP that complete the standard type of postdictions and predictions. Most of the dead wood still cluttering discussions on the meaning of Quantum Theory and the role of the BP is by-passed. We shall try to draw attention to the physics of this unfortunately hardly known novel formulation of Quantum Theory by giving additional illustrative examples inspired from the daily practices of contemporary Nuclear and Particle Physics, subjects that as yet have not been thoroughly reinterpreted within the BP. These fields of research offer excellent oppurtunities for explaining and illustrating the significance of time in quantum transitions, as well as the closely related features of quantum non-locality and quantum wholeness, as hard physical facts. We claim that in addition we can obtain a substantial gain in predictive powers of the underlying, all-encompassing, Quantum Theory.

  7. Development of phonon-mediated cryogenic particle detectors with electron and nuclear recoil discrimination

    Science.gov (United States)

    Nam, Sae Woo

    1999-10-01

    Observations have shown that galaxies, including our own, are surrounded by halos of ``dark matter''. One possibility is that this may be an undiscovered form of matter, weakly interacting massive particles (WIMPs). This thesis describes the development of silicon based cryogenic particle detectors designed to directly detect interactions with these WIMPs. These detectors are part of a new class of detectors which are able to reject background events by simultaneously measuring energy deposited into phonons versus electron hole pairs. By using the phonon sensors with the ionization sensors to compare the partitioning of energy between phonons and ionizations we can discriminate between electron recoil events (background radiation) and nuclear recoil events (dark matter events). These detectors with built-in background rejection are a major advance in background rejection over previous searches. Much of this thesis will describe work in scaling the detectors from / g prototype devices to a fully functional prototype 100g dark matter detector. In particular, many sensors were fabricated and tested to understand the behavior of our phonon sensors, Quasipartice trapping assisted Electrothermal feedback Transition edge sensors (QETs). The QET sensors utilize aluminum quasiparticle traps attached to tungsten superconducting transition edge sensors patterned on a silicon substrate. The tungsten lines are voltage biased and self-regulate in the transition region. Phonons from particle interactions within the silicon propogate to the surface where they are absorbed by the aluminum generating quasiparticles in the aluminum. The quasiparticles diffuse into the tungsten and couple energy into the tungsten electron system. Consequently, the tungsten increases in resistance and causes a current pulse which is measured with a high bandwidth SQUID system. With this advanced sensor technology, we were able to demonstrate detectors with xy position sensitivity with electron and

  8. Porous Chromatographic Materials as Substrates for Preparing Synthetic Nuclear Explosion Debris Particles

    International Nuclear Information System (INIS)

    Harvey, Scott D.; Liezers, Martin; Antolick, Kathryn C.; Garcia, Ben J.; Sweet, Lucas E.; Carman, April J.; Eiden, Gregory C.

    2013-01-01

    In this study, we investigated several porous chromatographic materials as synthetic substrates for preparing surrogate nuclear explosion debris particles. The resulting synthetic debris materials are of interest for use in developing analytical methods. Eighteen metals, including some of forensic interest, were loaded onto materials by immersing them in metal solutions (556 mg/L of each metal) to fill the pores, applying gentle heat (110°C) to drive off water, and then treating them at high temperatures (up to 800°C) in air to form less soluble metal species. High-boiling-point metals were uniformly loaded on spherical controlled-pore glass to emulate early fallout, whereas low-boiling-point metals were loaded on core-shell silica to represent coated particles formed later in the nuclear fallout-formation process. Analytical studies were applied to characterize solubility, material balance, and formation of recalcitrant species. Dissolution experiments indicated loading was 1.5 to 3 times higher than expected from the pore volume alone, a result attributed to surface coating. Analysis of load solutions before and after filling the material pores revealed that most metals were passively loaded; that is, solutions filled the pores without active metal discrimination. However, niobium and tin concentrations were lower in solutions after pore filling, and were found in elevated concentrations in the final products, indicating some metals were selectively loaded. High-temperature treatments caused reduced solubility of several metal species, and loss of some metals (rhenium and tellurium) because volatile species were formed. Sample preparation reproducibility was high (the inter-batch relative standard deviation was 7.8%, and the intra-batch relative standard deviation was 0.84%) indicating that this material is suitable for use as a working standard for analytical methods development. We anticipate future standardized radionuclide-loaded materials will find use in

  9. Behaviour of model particles of local precipitations of surface nuclear explosion in food chain and digestive tract of farm animals

    International Nuclear Information System (INIS)

    Koz'min, G.V.; Epimakhov, V.G.; Sanzharova, N.I.

    2016-01-01

    The behaviour regularities of radioactive particles - simulators of nuclear surface explosion local fall outs in food chain and gastrointestinal tract (GIT) of farm animals are analyzed. The results show that there is a large difference in transport regularities of radioactive silicate particles and radioactive solutions in GIT. At intake of young fission products high concentrations of radionuclides in GIT content deal with sorption and concentrating of radionuclides on food particles and observe in third stomach, blind gut, terminals of middle and bung guts. Transport regularities of fused radioactive particles depend on digestive apparatus mobility, content consistency and morphological peculiarities of mucosa, which work towards transport slowing and storage of such particles in the part of sheep GIT with minimal dry substance content - abomasum [ru

  10. A multi-particle model applicable to social issues--time-evolution of Japanese public opinion on nuclear energy

    International Nuclear Information System (INIS)

    Ohnishi, Teruaki

    2002-01-01

    The characteristics of an interacting multi-particle system in natural sciences can form a useful model for the evolution of public attitudes and opinions, provided that each particle corresponds to one individual. A simulation model which uses a multi-particle system to represent society was developed. By using this model, the time evolution of the public attitudes to nuclear energy were investigated. The nuclear attitude of an individual was assumed to be influenced by three factors: a uniform information environment, mutual interactions between members of the public, and spontaneous recovery of the original attitude with time. Also the time-evolution of the socio-psychological position of members of the public was assumed to be given by a Langevin-type equation. Various attributes of individuals obtained by public opinion surveys together with data on the secular variation of availability of nuclear information were used as the input. By numerically solving the simultaneous differential equations for the system of a 1000 particles, the time behavior of Japanese public opinion regarding the promotion of nuclear generation was investigated. It was found from this calculation that the public aversion to nuclear energy is catastrophically aggravated with every large-scale nuclear accident, that the opinions of individual members of the public as to the value of nuclear energy were gradually attracted to a few views with time, and that the unification of such views occurred with the Chernobyl accident as a promoter. It also became clear that the public attitude at a particular time is governed by the information environment over several years immediately prior to that time

  11. The excitation of an independent-particle gas - classical or quantal - by a time-dependent potential well

    International Nuclear Information System (INIS)

    Blocki, J.; Skalski, J.; Swiatecki, W.J.

    1995-01-01

    A systematic numerical investigation of the excitation of a classical or quantal gas of non-interacting particles in a time-dependent potential well is described. The excitation energy was followed in time for one oscillation around the sphere for six types of deformation: spheroidal shapes and Legendre polynomial ripples P 2 , P 3 , P 4 , P 5 , P 6 , with relative rms amplitudes of 0.2. Ten different speeds of deformation and eleven different values of the diffuseness of the potential well were studied, making altogether 660 quantal and 660 classical time-dependent calculations. In the upper range of deformation speeds the quantal results for the non-integrable shapes P 3 -P 6 agree approximately with the wall formula for dissipation, the deviations being largely accounted for by the wave-mechanical suppression factor of Koonin et al. For low deformation speeds the dissipation becomes dominated by one or two avoided level crossings. (orig.)

  12. Experiences Gained from Independent Assessment in Licensing of Advanced I and C Systems in Nuclear Power Plants

    International Nuclear Information System (INIS)

    Lindner, Arndt B.; Wach, Dieter H.

    2003-01-01

    Operational benefits and enlarged functionality of modern technology, but also the physical and the technological aging of conventional instrumentation and control (I and C) systems, are motivations for modernization of I and C systems in nuclear power plants (NPPs). In case of safety-relevant I and C systems, the licensing authorities require the demonstration of sufficient safety of the systems.In several countries ongoing research and development projects are directed to provide a scientific basis and engineering solutions for cost-effective assessment of software-based I and C systems important to safety in NPPs. International initiatives have been started to develop a harmonized safety assessment methodology. The Institute for Safety Technology (ISTec) has been engaged in national and international programs as well as in establishing a two-phase qualification approach, which comprises a generic plant-independent qualification of hardware and software components and a plant-specific system qualification phase.In both generic qualification and plant-specific system qualification, ISTec has been involved as an independent third-party assessor for the relevant state authority. This paper reports experiences from the ISTec involvement in the assessment projects, e.g., in the assessment of the I and C important to safety in the new German High-Flux Research Reactor (FRM-2) in Munich and in the assessments of I and C modernization in NPPs of foreign countries (Bohunice, Slovak Republic; Paks, Hungary; and others). Conclusions are drawn from the experiences with respect to the practicability of the two-phase qualification concept and from the major findings in the plant-specific I and C assessments

  13. Strategic field No.5 'the origin of matter and the universe'. Toward interdisciplinary researches in particle, nuclear and astrophysics

    International Nuclear Information System (INIS)

    Aoki, Shinya

    2011-01-01

    Four main research subjects in the strategic field No. 5 'The origin of matter and the universe', planned to be investigated on 'Kei' super computer, are explained in detail, by focusing on interdisciplinary aspect of researches among particle, nuclear and astrophysics. (author)

  14. Abstract ID: 240 A probabilistic-based nuclear reaction model for Monte Carlo ion transport in particle therapy.

    Science.gov (United States)

    Maria Jose, Gonzalez Torres; Jürgen, Henniger

    2018-01-01

    In order to expand the Monte Carlo transport program AMOS to particle therapy applications, the ion module is being developed in the radiation physics group (ASP) at the TU Dresden. This module simulates the three main interactions of ions in matter for the therapy energy range: elastic scattering, inelastic collisions and nuclear reactions. The simulation of the elastic scattering is based on the Binary Collision Approximation and the inelastic collisions on the Bethe-Bloch theory. The nuclear reactions, which are the focus of the module, are implemented according to a probabilistic-based model developed in the group. The developed model uses probability density functions to sample the occurrence of a nuclear reaction given the initial energy of the projectile particle as well as the energy at which this reaction will take place. The particle is transported until the reaction energy is reached and then the nuclear reaction is simulated. This approach allows a fast evaluation of the nuclear reactions. The theory and application of the proposed model will be addressed in this presentation. The results of the simulation of a proton beam colliding with tissue will also be presented. Copyright © 2017.

  15. Improvements in the preparation of nuclear fuel elements with addition of a molding mixture to fuel particles

    International Nuclear Information System (INIS)

    Miertschin, G.N.; Leary, D.F.

    1975-01-01

    An improved molting mixture to be added to nuclear fuel particles for the preparation of nuclear fuel elements is presented. It consists of carbon and pitch particles and contains an additive reducing the final coke yield of the fuel mass formed. This additive is chosen from: polystyrene and copolymers of styrene and butadiene of molecular weight between 500 and 1000000; aromatic compounds of molecular weight between 75 and 300; saturated hydrocarbon polymers of molecular weight between 500 and 1000000. The additive may be camphor, naphthalene, anthracene, phenanthrene, dimethyl terephthalate or their mixtures and is present at a concentration of 5 to 50% by weight. The carbon particles used consist of powdered graphite. These fuel elements are intended for gas-cooled high-temperature reactors [fr

  16. Calculation of the probability of overlapping one family of nuclear levels with resonances of an independent family

    International Nuclear Information System (INIS)

    Difilippo, F.C.

    1982-01-01

    Calculations of the resonance integrals of particular isotopes in a mixture of isotopes show that the overlapping of the resonances of one isotope by resonances of other isotopes affects the final values of effective cross sections. The same effect might adversely influence those nondestructive techniques which assay fissile materials on the basis of resonance effects. Of relevance for these applications is the knowledge of the probability of overlapping resonances of a family of nuclear levels (class 1) with resonances of an independent family (class 2). For the sequence of class 1 resonances we calculate the probability distribution, p(delta), to find a class 2, first-neighbor resonance at distance (in energy) delta from a class 1 resonance; integration of p(delta) over the average finite width of the resonances would give the aforementioned probability of overlapping. Because a class 1 resonance can have a class 1 or a class 2 resonance as a first neighbor, the resultant p(delta) is not given by the distribution of spacings of the composite family

  17. Problems and experience of detecting particles on the beaches in the vicinity of the Dounreay nuclear site

    International Nuclear Information System (INIS)

    Adsley, Ian; Davies, Mike; McCulloch, George; Gerrard, Alan

    2007-01-01

    Available in abstract form only. Full text of publication follows: There are several instances where radioactive material has been released from nuclear sites and is now found in particulate form in the environment. Contamination in this form was identified on the beaches close to the Dounreay Nuclear site in the 1990's and since that time NUKEM Limited has provided a measurement service to the UKAEA to find and recover these particles. There are specific difficulties associated with detecting particles - as distinct from distributed activity - and this paper discusses some of the theoretical and practical problems that are encountered in monitoring for such particles. The viability and performance of several types and configurations of radiation detectors will be described, along with methods by which particles might be detected, given their response to buried particles. Practical solutions to these measurement problems are described. Three generations of vehicle mounted sensing systems are discussed - each including improvements to specific measurement problems. The reliability and failure mechanisms of the monitoring systems used will be discussed, together with remedial actions employed. Alongside the radiation technology has been the use of GPS and GIS technologies to provide area mapping at high spatial resolution. The other practical aspects of performing surveys are also discussed, including understanding health-and-safety requirements; constraints imposed by weather, tides and tidal speed; the logistics of making vehicles. The results of all the particle finds to date will be presented and compared to the anticipated detection limits, derived from computer modeling and experimental studies. (authors)

  18. Analysis of the size of sandstone particles from the Cathedrals of Salamanca. Independence between granulometry and deterioration

    Directory of Open Access Journals (Sweden)

    Martín Patino, M. T.

    1994-03-01

    Full Text Available 11 sandstone samples from the cathedrals of Salamanca were analysed granulometrically. The study was to establish whether there is a direct connection between the particle size of such stone and the surface deterioration of some of the ashlars in the facades. This was carried out with the help of diffraction spectrometry by laser beams. The results show that there is no connection between the nature of the stone texture and their degree of surface deterioration.

    Se analizan granulométricamente 11 muestras de arenisca de las Catedrales de Salamanca. El objetivo del estudio es establecer si existe relación directa entre el tamaño de las partículas de tales piedras y el deterioro superficial de alguno de los sillares de las fachadas. Esto se lleva a cabo con la ayuda de la espectrometría de difracción por rayos láser. Los resultados muestran que no hay conexión entre la finura textural de las piedras estudiadas y el grado de deterioro superficial que éstas presentan.

  19. Particle size dependence of the Young's modulus of filled polymers: 2. Annealing and solid-state nuclear magnetic resonance experiments

    NARCIS (Netherlands)

    Vollenberg, P.H.T.; Haan, de J.W.; Ven, van de L.J.M.; Heikens, D.

    1989-01-01

    Experimental results are reported from which it appears that in the case of polymer filled with silane-treated glass beads the Young's modulus is, in accordance with present theory, independent of the particle size of the filler. However, if pure glass beads are used as filler, the Young's modulus

  20. Internet end-to-end performance monitoring for the High Energy Nuclear and Particle Physics community

    Energy Technology Data Exchange (ETDEWEB)

    Matthews, W.

    2000-02-22

    Modern High Energy Nuclear and Particle Physics (HENP) experiments at Laboratories around the world present a significant challenge to wide area networks. Petabytes (1015) or exabytes (1018) of data will be generated during the lifetime of the experiment. Much of this data will be distributed via the Internet to the experiment's collaborators at Universities and Institutes throughout the world for analysis. In order to assess the feasibility of the computing goals of these and future experiments, the HENP networking community is actively monitoring performance across a large part of the Internet used by its collaborators. Since 1995, the pingER project has been collecting data on ping packet loss and round trip times. In January 2000, there are 28 monitoring sites in 15 countries gathering data on over 2,000 end-to-end pairs. HENP labs such as SLAC, Fermi Lab and CERN are using Advanced Network's Surveyor project and monitoring performance from one-way delay of UDP packets. More recently several HENP sites have become involved with NLANR's active measurement program (AMP). In addition SLAC and CERN are part of the RIPE test-traffic project and SLAC is home for a NIMI machine. The large End-to-end performance monitoring infrastructure allows the HENP networking community to chart long term trends and closely examine short term glitches across a wide range of networks and connections. The different methodologies provide opportunities to compare results based on different protocols and statistical samples. Understanding agreement and discrepancies between results provides particular insight into the nature of the network. This paper will highlight the practical side of monitoring by reviewing the special needs of High Energy Nuclear and Particle Physics experiments and provide an overview of the experience of measuring performance across a large number of interconnected networks throughout the world with various methodologies. In particular, results

  1. Characteristics and fabrication of cermet spent nuclear fuel casks: ceramic particles embedded in steel

    Energy Technology Data Exchange (ETDEWEB)

    Forsberg, C.W.; Swaney, P.M.; Tiegs, T.N. [Oak Ridge National Lab., Oak Ridge, TN (United States)

    2004-07-01

    Cermets are being investigated as an advanced material of construction for casks that can be used for storage, transport, or disposal of spent nuclear fuel (SNF). Cermets, which consist of ceramic particles embedded in steel, are a method to incorporate brittle ceramics with highly desirable properties into a strong ductile metal matrix with a high thermal conductivity, thus combining the best properties of both materials. Traditional applications of cermets include tank armor, vault armor, drill bits, and nuclear test-reactor fuel. Cermets with different ceramics (DUO{sub 2}, Al{sub 2}O{sub 3}, Gd{sub 2}O{sub 3}, etc.) are being investigated for the manufacture of SNF casks. Cermet casks offer four potential benefits: greater capacity (more SNF assemblies) for the same gross weight cask, greater capacity (more SNF assemblies) for the same external dimensions, improved resistance to assault, and superior repository performance. These benefits are achieved by varying the composition, volume fraction, and particulate size of the ceramic particles in the cermet with position in the cask body. Addition of depleted uranium dioxide (DUO{sub 2}) to the cermet increases shielding density, improves shielding effectiveness, and increases cask capacity for a given cask weight or size. Addition of low-density aluminium oxide (Al{sub 2}O{sub 3}) to the outer top and bottom sections of the cermet cask, where the radiation levels are lower, can lower cask weight without compromising shielding. The use of Al2O3 and other oxides, in appropriate locations, can increase resistance to assault. Repository performance may be improved by compositional control of the cask body to (1) create a local geochemical environment that slows the long-term degradation of the SNF and (2) enables the use of DUO{sub 2} for longterm criticality control. While the benefits of using cermets follow directly from their known properties, the primary challenge is to develop low-cost methods to fabricate

  2. Internet end-to-end performance monitoring for the High Energy Nuclear and Particle Physics community

    International Nuclear Information System (INIS)

    Matthews, W.

    2000-01-01

    Modern High Energy Nuclear and Particle Physics (HENP) experiments at Laboratories around the world present a significant challenge to wide area networks. Petabytes (1015) or exabytes (1018) of data will be generated during the lifetime of the experiment. Much of this data will be distributed via the Internet to the experiment's collaborators at Universities and Institutes throughout the world for analysis. In order to assess the feasibility of the computing goals of these and future experiments, the HENP networking community is actively monitoring performance across a large part of the Internet used by its collaborators. Since 1995, the pingER project has been collecting data on ping packet loss and round trip times. In January 2000, there are 28 monitoring sites in 15 countries gathering data on over 2,000 end-to-end pairs. HENP labs such as SLAC, Fermi Lab and CERN are using Advanced Network's Surveyor project and monitoring performance from one-way delay of UDP packets. More recently several HENP sites have become involved with NLANR's active measurement program (AMP). In addition SLAC and CERN are part of the RIPE test-traffic project and SLAC is home for a NIMI machine. The large End-to-end performance monitoring infrastructure allows the HENP networking community to chart long term trends and closely examine short term glitches across a wide range of networks and connections. The different methodologies provide opportunities to compare results based on different protocols and statistical samples. Understanding agreement and discrepancies between results provides particular insight into the nature of the network. This paper will highlight the practical side of monitoring by reviewing the special needs of High Energy Nuclear and Particle Physics experiments and provide an overview of the experience of measuring performance across a large number of interconnected networks throughout the world with various methodologies. In particular, results from each project

  3. Characteristics and fabrication of cermet spent nuclear fuel casks: ceramic particles embedded in steel

    International Nuclear Information System (INIS)

    Forsberg, C.W.; Swaney, P.M.; Tiegs, T.N.

    2004-01-01

    Cermets are being investigated as an advanced material of construction for casks that can be used for storage, transport, or disposal of spent nuclear fuel (SNF). Cermets, which consist of ceramic particles embedded in steel, are a method to incorporate brittle ceramics with highly desirable properties into a strong ductile metal matrix with a high thermal conductivity, thus combining the best properties of both materials. Traditional applications of cermets include tank armor, vault armor, drill bits, and nuclear test-reactor fuel. Cermets with different ceramics (DUO 2 , Al 2 O 3 , Gd 2 O 3 , etc.) are being investigated for the manufacture of SNF casks. Cermet casks offer four potential benefits: greater capacity (more SNF assemblies) for the same gross weight cask, greater capacity (more SNF assemblies) for the same external dimensions, improved resistance to assault, and superior repository performance. These benefits are achieved by varying the composition, volume fraction, and particulate size of the ceramic particles in the cermet with position in the cask body. Addition of depleted uranium dioxide (DUO 2 ) to the cermet increases shielding density, improves shielding effectiveness, and increases cask capacity for a given cask weight or size. Addition of low-density aluminium oxide (Al 2 O 3 ) to the outer top and bottom sections of the cermet cask, where the radiation levels are lower, can lower cask weight without compromising shielding. The use of Al2O3 and other oxides, in appropriate locations, can increase resistance to assault. Repository performance may be improved by compositional control of the cask body to (1) create a local geochemical environment that slows the long-term degradation of the SNF and (2) enables the use of DUO 2 for longterm criticality control. While the benefits of using cermets follow directly from their known properties, the primary challenge is to develop low-cost methods to fabricate casks with variable cermet compositions

  4. Particles identification using nuclear emulsion in OPERA; Identification des particules par les emulsions nucleaires dans OPERA

    Energy Technology Data Exchange (ETDEWEB)

    Manai, K

    2007-10-15

    The Opera experiment will try to confirm the {nu}{sub {mu}} {yields} {nu}{sub {tau}} oscillations by the appearance of the {nu}{sub {tau}} in a pure {nu}{sub {mu}} beam. Indeed, a neutrino beam almost pure is produced at CERN (CNGS Beam) and sent to the Opera detector. The detector is composed of two muons spectrometers and a target formed by walls of bricks. Each brick is an alternation of lead plates and emulsions. This modular structure allows to reconstruct the kink topology of the {tau} lepton decay with a high spatial resolution. The great challenge of the Opera experiment is to detect the {nu}{sub {tau}} interactions with the less uncertainty. To reduce this uncertainty it is essential to identify with the greatest efficiency any background event not including a tau particle. My work permits to reduce background. My principal contribution concerns the selection development, the reconstruction and the muons identification at low energy. This work is based on the setting of variables related to the deposit energy and the multiple scattering. Previously, only deposit energy was used in the analyses of pion/muon separation. This study allows doubling the muon identification efficiency at low energy. This leads to increase the background events rejection in Opera and to decrease the contamination by 30%. I also studied the nuclear emulsions capacity to identify charged particles through the analysis of a test beam carried out by the Nagoya group. This test contains protons and pions with different energies. My work proves that the European scan system gives comparable results with those obtained by the Japanese scan system. (author)

  5. Effect of free-particle collisions in high energy proton and pion-induced nuclear reactions

    International Nuclear Information System (INIS)

    Jacob, N.P. Jr.

    1975-07-01

    The effect of free-particle collisions in simple ''knockout'' reactions of the form (a,aN) and in more complex nuclear reactions of the form (a,X) was investigated by using protons and pions. Cross sections for the 48 Ti(p,2p) 47 Sc and the 74 Ge(p,2p) 73 Ga reactions were measured from 0.3 to 4.6 GeV incident energy. The results indicate a rise in (p,2p) cross section for each reaction of about (25 +- 3) percent between the energies 0.3 and 1.0 GeV, and are correlated to a large increase in the total free-particle pp scattering cross sections over the same energy region. Results are compared to previous (p,2p) excitation functions in the GeV energy region and to (p,2p) cross section calculations based on a Monte Carlo intranuclear cascade-evaporation model. Cross section measurements for (π/sup +-/, πN) and other more complex pion-induced spallation reactions were measured for the light target nuclei 14 N, 16 O, and 19 F from 45 to 550 MeV incident pion energy. These measurements indicate a broad peak in the excitation functions for both (π,πN) and (π,X) reactions near 180 MeV incident energy. This corresponds to the large resonances observed in the free-particle π + p and π - p cross sections at the same energy. Striking differences in (π,πN) cross section magnitudes are observed among the light nuclei targets. The experimental cross section ratio sigma(π - ,π - n)/sigma(π + ,πN) at 180 MeV is 1.7 +- 0.2 for all three targets. The experimental results are compared to previous pion and analogous proton-induced reactions, to Monte Carlo intranuclear cascade-evaporation calculations, and to a semi-classical nucleon charge exchange model. (108 references) (auth)

  6. Dual Neutral Particle Beam Interrogation of Intermodal Shipping Containers for Special Nuclear Material

    Science.gov (United States)

    Keith, Rodney Lyman

    Intermodal shipping containers entering the United States provide an avenue to smuggle unsecured or stolen special nuclear material (SNM). The only direct method fielded to indicate the presence of SNM is by passive photon/neutron radiation detection. Active interrogation using neutral particle beams to induce fission in SNM is a method under consideration. One by-product of fission is the creation of fragments that undergo radioactive decay over a time period on the order of tens of seconds after the initial event. The "delayed" gamma-rays emitted from these fragments over this period are considered a hallmark for the presence of SNM. A fundamental model is developed using homogenized cargos with a SNM target embedded at the center and computationally interrogated using simultaneous neutron and photon beams. Findings from analysis of the delayed gamma emissions from these experiments are intended to mitigate the effects of poor quality information about the composition and disposition of suspect cargo before examination in an active interrogation portal.

  7. Inclusive characteristics of the nuclear target fragmentation products induced by relativistic particles

    International Nuclear Information System (INIS)

    Bogatin, V.I.; Ganza, E.A.; Lozhkin, O.V.; Murin, Yu.A.; Oplavin, V.S.; Perfilov, N.A.; Yakovlev, Yu.P.

    1981-01-01

    An experimental investigation of inclusive characteristics of nuclei-target fragmentation is conducted for further development and test of physical value of the earlier suggested nuclear fragmentation model based on the connection of the fragmentation with fluctuations of the quasiparticle density in the two-component quantum liquid, an experimental investigation of the inclusive characteristics of the nuclei-target fragmentation is carried out. The processes of sup(3, 4, 6, 8)He and sup(6, 7, 8, 9, 11)Li fragment formation during the interaction of relativistic protons (Esub(p)=6.7 GeV) and deutrons (Esub(d)=3.1 GeV) with 112 Sn and 124 Sn isotopes are studied by the method of semiconductive ΔE-E detectors. Differential energy spectra of fragments and isotopic ratio of cross sections of their formation as well as data on the dependence of isotopic ratios of fragmentation cross sections on the energy of incident particles and on the fragment energy are obtained. Presented is a phenomenological model of fragmentation within the frames of which the obtained experimental data are analyzed [ru

  8. Confined dense particle-gas flow, application to nuclear fuel relocation

    International Nuclear Information System (INIS)

    Martin, A.

    2010-02-01

    In this work, we investigate particle-gas two-phase flows in the jamming regime where the flow stops in finite time. In this regime, which occurs quite often in nature and industrial applications, the flow is stochastic and needs therefore to be characterized by the jamming probability as well as the flow rate and its fluctuations that depend on the confining geometry, granular microstructure and gas properties. We developed a numerical approach based on the coupling of the Non Smooth Contact Dynamics for the solid phase and a mesoscopic method for the gas phase. We find that the flow rate as a function of the opening is well fit by a power law in agreement with reported experimental data. The presence of a gas affects only the mean flow rate, the flow statistics being sensibly the same as in the absence of the gas. We apply our quantitative statistical results in order to estimate the relocation rate of fragmented nuclear fuel inside its cladding tube as a result of a local balloon caused by an accident (loss-of-coolant accident). (author)

  9. Analysis format and evaluation methods for effluent particle sampling systems in nuclear facilities

    International Nuclear Information System (INIS)

    Schwendiman, L.C.; Glissmeyer, J.A.

    1976-06-01

    Airborne effluent sampling systems for nuclear facilities are frequently designed, installed, and operated without a systematic approach which discloses and takes into account all the circumstances and conditions which would affect the validity and adequacy of the sample. Without a comprehensive check list or something similar, the designer of the system may not be given the important information needed to provide a good design. In like manner, an already operating system may be better appraised. Furthermore, the discipline of a more formal approach may compel the one who will use the system to make sure he knows what he wants and can thus give the designer the needed information. An important consideration is the criteria to be applied to the samples to be taken. This analysis format consists of a listing of questions and statements calling forth the necessary information required to analyze a sampling system. With this information developed, one can proceed with an evaluation, the methodology of which is also discussed in the paper. Errors in probe placement, failure to sample at the proper rate, delivery line losses, and others are evaluated using mathematical models and empirically derived relationships. Experimental methods are also described for demonstrating that quality sampling will be achieved. The experiments include using a temporary, simple, but optimal sample collection system to evaluate the more complex systems. The use of tracer particles injected in the stream is also discussed. The samples obtained with the existing system are compared with those obtained by the temporary, optimal system

  10. Automaton for spectra measurement of charged particles detected in nuclear photoemulsions

    International Nuclear Information System (INIS)

    Bauehr, R.; Krzhemenek, Ya.; Piskorzh, Sh.; Svoboda, Z.; Shkaba, V.

    1978-01-01

    The electronic equipment is described for measuring the spectra of charged particles detected in nuclear photoemulsions. With regard to function, the electronic equipment may be classified as follows: unit for analog processing of signals, logic for track recognition and device for controlling and recording measurement results. The analog processing unit incorporates eight identical channels, each of which consists of a flexible light pipe, a photomultiplier, an amplifier, an amplitude analyzer, and a marker. Eight memory shift registers forming a data field are used for determining the presence of a track in an emulsion area being analyzed. The following track recognition criteria are used: (a) trace image in a logical form forms a continuous path in the register field; (b) the length of the continuous image should constitute at least five channels; and (c) tracks longer than five channels are recorded only once. The scanning plates of 700 mm long takes three hours. Accuracy of determination of the longitudinal coordinate is 25 μm

  11. Energy of nuclear-active particles in the 1-50 TeV energy range

    International Nuclear Information System (INIS)

    Kotlyarevskij, D.M.; Garsevanishvili, L.P.; Morozov, I.V.

    1979-01-01

    The ''TsKhRA-TsKARO'' installation designed for the investigation of cosmic beams interaction with nuclei in the energy range of 1-50 TeV is described. The installation comprises a magnetic spark spectrometer, photography system, ionization calorimeter and scintillating trigger device. The ionization calorimeter contains 12 rows of ionization chambers interlayed with 4 lead and 8 iron absorbers. The rows of ionization chambers of the calorimeter upper half are placed in the mutually-perpendicular direction to restore the direction and spatial situation of the electron-nuclear cascade. All in all the ionization calorimeter contains 100 channels of preintensifiers from which the information is transmitted to the terminal intensifiers and then to the storage cells. The aperture ratio of the whole installation (taking account of the upper chambers) is 0.5 m 2 /steradian, and the aperture ratio of the calorimeter together with the lower chambers is approximately 2 m 2 /steradian. Presented are integral spectra of the hadrons at the height of mountains and at the height of 2500 m above sea level obtained with the help of the installation described. Comparison of the number of charged and neutral particles recorded with the ''TsKhRA-TsKARO'' installation agrees well with the known ratio of charged and neutral cosmic hadrons on the heights of mountains n/c = 0.52+-0.05

  12. A semi-classical model for the description of angular distribution of light particles emitted in nuclear reactions

    International Nuclear Information System (INIS)

    Zhang Jingshang

    1990-04-01

    A semi-classical model of multi-step direct and compound nuclear reactions has been proposed to describe the angular distributions of light particles emitted in reaction processes induced by nucleons with energies of several tens of MeV. The exact closed solution for the time-dependent master equation of the exciton model is applied. Based on the Fermi gas model, the scattering kernel for two-nucleon collisions includes the influence of the Fermi motion and the Pauli exclusion principle, which give a significant improvement in the description of the rise of the backward distributions. The angle-energy correlation for the first few steps of the collision process (multi-step direct process) yields further improvements in the description of the angular distribution. The pick-up mechanism is employed to describe the composite particle emission. This reasonable physical picture reproduces the experimental data of the energy spectra of composite particles satisfactorily. The angular distribution of the emitted composite particles is determined by an angular factor in terms of the momentum conservation of the nucleons forming the composite cluster. The generalized master equation is employed for the multi-step compound process. Thus a classical approach has been established to calculate the double differential cross sections for all kinds of particles emitted in multi-step nuclear reaction processes. (author). 19 refs, 6 figs, 1 tab

  13. Application of nuclear techniques to the measurement of rock density and transport of solid particles suspended in rivers

    International Nuclear Information System (INIS)

    Seddiki, A.

    1984-10-01

    In order to better understand hydron phenomens in semi-arid regions characterized by torrential rains, we measured solid particles suspended to dums and in rivers. We also determined the density profile of a drilling and density of saline solutions. We designed an automatic nuclear gauge used for measuring the concentration of particles suspended to rivers. The installation, calibration and operations of a LABEN gauge were done in BENI SLIMANE on the 27th and 28th of February, 1984. The first results we obtained were received on the 24th of April, 1984

  14. Caspase-independent cell death mediated by apoptosis-inducing factor (AIF) nuclear translocation is involved in ionizing radiation induced HepG2 cell death

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Hengwen [Department of Radiation, Cancer Center of Guangdong General Hospital (Guangdong Academy of Medical Science), Guangzhou, 510080, Guangdong (China); Yang, Shana; Li, Jianhua [Department of Physiology, Guangzhou Medical University, Guangzhou, 510182, Guangdong (China); Zhang, Yajie [Department of Pathology, Guangzhou Medical University, Guangzhou, 510182, Guangdong (China); Gao, Dongsheng [Department of Oncology, Guangdong Medical College Affiliated Pengpai Memorial Hospital, Hai Feng, 516400, Gungdong (China); Zhao, Shenting, E-mail: zhaoshenting@126.com [Department of Physiology, Guangzhou Medical University, Guangzhou, 510182, Guangdong (China)

    2016-03-25

    Hepatocellular carcinoma (HCC) is the fifth most common cancer in the world. The aim of radiotherapy is to eradicate cancer cells with ionizing radiation. Except for the caspase-dependent mechanism, several lines of evidence demonstrated that caspase-independent mechanism is directly involved in the cell death responding to irradiation. For this reason, defining the contribution of caspase-independent molecular mechanisms represents the main goal in radiotherapy. In this study, we focused on the role of apoptosis-inducing factor (AIF), the caspase-independent molecular, in ionizing radiation induced hepatocellular carcinoma cell line (HepG2) cell death. We found that ionizing radiation has no function on AIF expression in HepG2 cells, but could induce AIF release from the mitochondria and translocate into nuclei. Inhibition of AIF could reduce ionizing radiation induced HepG2 cell death. These studies strongly support a direct relationship between AIF nuclear translocation and radiation induced cell death. What's more, AIF nuclear translocation is caspase-independent manner, but not caspase-dependent manner, in this process. These new findings add a further attractive point of investigation to better define the complex interplay between caspase-independent cell death and radiation therapy. - Highlights: • AIF nuclear translocation is involved in ionizing radiation induced hepatocellular carcinoma cell line HepG2 cell death. • AIF mediated cell death induced by ionizing radiation is caspase-independent. • Caspase-independent pathway is involved in ionzing radiation induced HepG2 cell death.

  15. UCTM2: An updated User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Bourrion, O., E-mail: olivier.bourrion@lpsc.in2p3.fr; Boyer, B.; Derome, L.; Pignol, G.

    2016-06-11

    We developed a highly integrated and versatile electronic module to equip small nuclear physics experiments and lab teaching classes: the User friendly Configurable Trigger, scaler and delay Module for nuclear and particle physics (UCTM). It is configurable through a Graphical User Interface (GUI) and provides a large number of possible trigger conditions without any Hardware Description Language (HDL) required knowledge. This new version significantly enhances the previous capabilities by providing two additional features: signal digitization and time measurements. The design, performances and a typical application are presented.

  16. Application of the beta particles backscattering technique for determining the thickness of the cladding in nuclear fuels plate

    International Nuclear Information System (INIS)

    Koshimizu, S.; Ferreira, P.I.; Lima, L.F.C.P. de; Vieira, J.M.; Perez, H.E.B.

    1984-01-01

    A prototype of an instalation to measure thickness of cladding and core of nuclear fuels plate using the beta particles backscattering technique is constructed. The method and calibration system is described. The thickness measurements of the cladding and core were done in a natural uranium fuel plate developed at IPEN. The reliability of the method is confirmed by the metalographic measures analysis. (E.G.) [pt

  17. The 15th AINSE nuclear and particle conference at the 6th APPC and 11th AIP congress

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    The 1994 AINSE conference was held in Brisbane, at Griffith University in conjunction with the 6th APPC and the 11th Australian Institute of Physics Congress. It focused on physics of elementary particles and fields, nuclear reactions and scattering, neutrinos and dark matter. The proceedings booklet contains the conference programme and talks summaries. Seventy one papers out of the 73 contributions were indexed separately for inclusion in the INIS database.

  18. Preface: II Russian-Spanish Congress on Particle and Nuclear Physics at All Scales, Astroparticle Physics and Cosmology

    OpenAIRE

    Andrianov, Alexander A.; Espriu, D. (Domènec); Andrianov, Vladimir A.; Kolevatov, S.

    2014-01-01

    This publication contains the proceedings of the II Russian-Spanish Congress on Particle and Nuclear Physics at All Scales, Astroparticle Physics and Cosmology, a collection of refereed papers presented in plenary and parallel sessions at a meeting that gathered leading Russian and Spanish Scientists in the above fields in Saint-Petersburg from October 1st through October 4th 2013 (http://hep.phys.spbu.ru/conf/esp-rus2013/).

  19. The 15th AINSE nuclear and particle conference at the 6th APPC and 11th AIP congress

    International Nuclear Information System (INIS)

    1994-01-01

    The 1994 AINSE conference was held in Brisbane, at Griffith University in conjunction with the 6th APPC and the 11th Australian Institute of Physics Congress. It focused on physics of elementary particles and fields, nuclear reactions and scattering, neutrinos and dark matter. The proceedings booklet contains the conference programme and talks summaries. Seventy one papers out of the 73 contributions were indexed separately for inclusion in the INIS database

  20. U1 small nuclear RNA variants differentially form ribonucleoprotein particles in vitro.

    Science.gov (United States)

    Somarelli, Jason A; Mesa, Annia; Rodriguez, Carol E; Sharma, Shalini; Herrera, Rene J

    2014-04-25

    The U1 small nuclear (sn)RNA participates in splicing of pre-mRNAs by recognizing and binding to 5' splice sites at exon/intron boundaries. U1 snRNAs associate with 5' splice sites in the form of ribonucleoprotein particles (snRNPs) that are comprised of the U1 snRNA and 10 core components, including U1A, U1-70K, U1C and the 'Smith antigen', or Sm, heptamer. The U1 snRNA is highly conserved across a wide range of taxa; however, a number of reports have identified the presence of expressed U1-like snRNAs in multiple species, including humans. While numerous U1-like molecules have been shown to be expressed, it is unclear whether these variant snRNAs have the capacity to form snRNPs and participate in splicing. The purpose of the present study was to further characterize biochemically the ability of previously identified human U1-like variants to form snRNPs and bind to U1 snRNP proteins. A bioinformatics analysis provided support for the existence of multiple expressed variants. In vitro gel shift assays, competition assays, and immunoprecipitations (IPs) revealed that the variants formed high molecular weight assemblies to varying degrees and associated with core U1 snRNP proteins to a lesser extent than the canonical U1 snRNA. Together, these data suggest that the human U1 snRNA variants analyzed here are unable to efficiently bind U1 snRNP proteins. The current work provides additional biochemical insights into the ability of the variants to assemble into snRNPs. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Relationship between particle size and radiocesium in fluvial suspended sediment related to the Fukushima Daiichi Nuclear Power Plant accident

    International Nuclear Information System (INIS)

    Kazuya Tanaka

    2014-01-01

    We collected fluvial suspended sediments in Fukushima after the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident and analyzed the 137 Cs concentration in bulk and size-fractioned samples to investigate the particle-size-dependent distribution of radiocesium. The 137 Cs concentration in bulk suspended sediments decreased from August to December 2011, possibly reflecting a decrease of radiocesium concentration in its source materials. Smaller particles had higher radiocesium concentrations, reflecting larger specific surface areas. Silt- and sand-size fractions occupied more than 95 % of the total 137 Cs in the suspended sediments. The contribution of clay-size fractions, which had the highest 137 Cs concentration, was quite small because of their low frequency. A line of the data showed that the particle size distribution of radiocesium was essential to evaluate the migration and distribution of radiocesium in river systems where radiocesium is mainly present as particulate form after the FDNPP accident. (author)

  2. New possibility for high-resolution spectroscopy of nuclear particles entering CR-39 at selected dip angles

    Energy Technology Data Exchange (ETDEWEB)

    Somogyi, G.; Hunyadi, I.; Hafez, A.F. (Magyar Tudomanyos Akademia, Debrecen. Atommag Kutato Intezete); Espinosa, G. (Universidad Nacional Autonoma de Mexico, Mexico City. Inst. de Fisica)

    1984-01-01

    In nuclear reaction studies a differentiation of the reaction products according to their type and energy is generally required. At right angle of incidence a particle identification method based on the relation between the track diameter and particle energy can be well applied to plastic track detectors of low registration sensitivity. We have tried to extend this 'track-diameter method' to the high-sensitivity CR-39 sheets by selecting special incident angles for particle detection. The utility of such a measuring procedure, called 'track-size method', is presented for alpha and proton spectroscopy. A theory is developed to calculate at arbitrary angles the main parameters affecting the energy resolving power of the 'track-size method', namely the critical layer thickness (which has to be removed from the detector surface for track-induction) and the depth and minor axis of etch-pits.

  3. Proceedings of the eighth Nuclear and Particle Physics Conference (NUPPAC-2011)

    International Nuclear Information System (INIS)

    2011-11-01

    The proceeding contains of 287 pages, the available maertial of 50 contributions: and covering of conference topics: Plenary, Invited, Keynote Talks. Nuclear Structure and Spectroscopy. Nuclear Scattering and Reactions. Neutron and Reactor Physics. Relativistic and Quantum Physics. Detectors and Instrumentation. Nuclear Analytical Techniques. Radiation Measurement and Dosimetry.

  4. Device for the separation of spherically shaped fuel or breeding material particles for nuclear reactors

    International Nuclear Information System (INIS)

    Gyarmati, E.; Muenzer, R.

    1974-01-01

    Spherical fuel or blanket material particles are graded by diameter. The particles, which are present in a loose pebble bed, are singulized by means of a drum and by pneumatic suction. Next they pass through a drop section past an optical barrier which generates pulses corresponding to the number of particles. The particles then run through an eccentric wheel. This generates an electric voltage across a potentiometer which corresponds to the size of the particles. The slider of the potentiometer is connected with the axle of the eccentric wheel whose distance to the wall of the drop canal varies between the largest and the smallest possible diameters of the particles over half a revolution. Another barrier downstream of the eccentric wheel causes the particles to be graded in different containers in accordance with their diameters determined in this way. (DG) [de

  5. A conceptual study of the use of a particle bed reactor nuclear propulsion module for the orbital maneuvering vehicle

    International Nuclear Information System (INIS)

    Malloy, J.; Potekhen, D.

    1989-01-01

    This paper examines the use of a particle bed reactor nuclear engine for direct thrust in a spacecraft based on the NASA/TRW orbital maneuvering vehicle (OMV). It presents the conceptual design of a 500 lb thrust engine that matches critical design features of the existing OMV bi-propellant propulsion system. This application contrasts with the usual tendency to consider a nuclear heat source either for high thrust direct propulsion or as a power source for electric propulsion. A nuclear propulsion module adapted to the OMV could potentially accomplish several Department of Defense missions, such as multiple round trips from a space-based support platform at 280 NM to service a constellation of satellites orbiting at 1800 NM

  6. Energy demands, goal of energy independence drives renewed interest in nuclear power in the U.S. and elsewhere

    International Nuclear Information System (INIS)

    Tritch, S.

    2002-01-01

    Worldwide energy consumption is going to rise in step with population growth and economic development. Forecasts indicate a growth of the electricity sector alone from the present annual requirement of 12 500 TWh to approx. 28 000 TWh in 2042. This challenge requires governments all over the world to find appropriate solutions which include economic and ecological aspects as well as those of energy policy, among others. In the United States, the goal of a balanced energy mix is to be reached by including all sources of energy, inclusive of a larger share of nuclear power. Nuclear power offers considerable advantages in a number of important factors. Nuclear power plants generate electricity in a cost-effective way, thus ensuring low prices in the energy mix. The use of nuclear power contributes to the conservation of other, natural energy resources, which makes it the only source of energy available which still offers a considerable further potential for use. Moreover, climate protection requires the use of nuclear power. In the United States alone, nuclear power today reduces emissions of carbon dioxide on a level comparable to 100 million road vehicles. This makes nuclear power an important part of energy supply worldwide and will allow it to play a major role in the future energy mix. The nuclear industry is prepared to meet this challenge. (orig.)

  7. An independent safety assessment of Department of Energy nuclear reactor facilities: Training of operating personnel and personnel selection

    International Nuclear Information System (INIS)

    Drain, J.F.

    1981-02-01

    This study has been prepared for the Department of Energy's Nuclear Facilities Personnel Qualification and Training (NFPQT) Committee. Its purpose is to provide the Committee with background information on, and assessment of, the selection, training, and qualification of nuclear reactor operating personnel at DOE-owned facilities

  8. Distribution of artificial radionuclides in particle-size fractions of soil on fallout plumes of nuclear explosions.

    Science.gov (United States)

    Kabdyrakova, A M; Lukashenko, S N; Mendubaev, A T; Kunduzbayeva, A Ye; Panitskiy, A V; Larionova, N V

    2018-06-01

    In this paper are analyzed the artificial radionuclide distributions ( 137 Cs, 90 Sr, 241 Am, 239+240 Pu) in particle-size fractions of soils from two radioactive fallout plumes at the Semipalatinsk Test Site. These plumes were generated by a low-yield surface nuclear test and a surface non-nuclear experiment with insignificant nuclear energy release, respectively, and their lengths are approximately 3 and 0,65 km. In contrast with the great majority of similar studies performed in areas affected mainly by global fallout where adsorbing radionuclides such as Pu are mainly associated with the finest soil fractions, in this study it was observed that along both analyzed plumes the highest activity concentrations are concentrated in the coarse soil fractions. At the plume generated by the surface nuclear test, the radionuclides are concentrated mainly in the 1000-500 μm soil fraction (enrichment factor values ranging from 1.2 to 3.8), while at the plume corresponding to the surface non-nuclear test is the 500-250 μm soil fraction the enriched one by technogenic radionuclides (enrichment factor values ranging from 1.1 to 5.1). In addition, the activity concentration distributions among the different soil size fractions are similar for all radionuclides in both plumes. All the obtained data are in agreement with the hypothesis indicating that enrichment observed in the coarse fractions is caused by the presence of radioactive particles resulted from the indicated nuclear tests. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Method for rapid particle size analysis by hydrosizing and nuclear sensing

    International Nuclear Information System (INIS)

    Daellenbach, C.B.; Mahan, W.M.

    1977-01-01

    A method and apparatus to practice the method for rapidly determining the size and mass distribution of a sample of randomly sized particles of a known total mass are described. A series of substantially identical hydrocyclones are connected by conduits to each other and to a temperature controlled water feed. By restricting the cross-sectional areas of these conduits to progressively smaller values, the slurry containing the sample particles is caused to increase its velocity as it moves from hydrocyclone to hydrocyclone. As described by the Stokesian theory which relates particle diameter and settling velocity, the largest sized particles are suspended in the closed apex of the first hydrocyclone with smaller sized particles, in given size ranges, being suspended in the next succeeding hydrocyclone's apexes. In this manner, the particles are separated into discrete fractional sizes with a residual slurry of the very smallest particles being discharged. Before the discrete fractions of particles are suspended in their hydrocyclone apexes, a combined photon source, like a gamma ray source, and detector are calibrated with the water temperature kept constant. When the suspension of particles takes place, an attenuation of the radiation from the source is observed at the detector. This attenuation can be related to the mass or weight of the discrete fractions of suspended particles. Electronic circuitry is used to indicate what this fractional mass or weight is as it relates to the total weight of the sample. 6 claims, 4 figs

  10. Radiological controls and worker and public health and safety: An independent safety assessment of Department of Energy nuclear reactor facilities

    International Nuclear Information System (INIS)

    Tew, J.L.; Miles, M.E.; Knuth, D.; Boyd, R.

    1981-02-01

    DOE has formed a Nuclear Facilities Personnel Qualification and Training (NFPQT) Committee to assess the implications of the Report of the President's Commission on the Accident at Three Mile Island that are applicable to DOE's nuclear reactor operations. Thirteen DOE nuclear reactors were reviewed by the Committee. This report was prepared to provide a measure of how the radiological control and environmental practices at the 13 individual DOE reactor facilities measure up to (1) the recommendations contained in the Report of the President's Commission on the Accident at Three Mile Island, (2) the requirements and guidelines contained, and (3) the requirements of the applicable Title and Part of the Code of Federal Regulations

  11. p53 nuclear accumulation and multiploidy are adverse prognostic factors in surgically resected stage II colorectal cancers independent of fluorouracil-based adjuvant therapy.

    Science.gov (United States)

    Buglioni, S; D'Agnano, I; Vasselli, S; Perrone Donnorso, R; D'Angelo, C; Brenna, A; Benevolo, M; Cosimelli, M; Zupi, G; Mottolese, M

    2001-09-01

    To identify the prognostically highest risk patients, DNA content and p53 nuclear or cytoplasmic accumulation, evaluated by monoclonal antibody DO7 and polyclonal antibody CM1, were determined in 94 surgically resected stage II (Dukes B2) colorectal cancers, treated or not with adjuvant 5-fluorouracil-based chemotherapy. Sixty-one (65%) of the tumors were aneuploid, 16 (17%) of which had a multiploid DNA content; 50 (53%) displayed DO7 nuclear p53 accumulation, and 44 (47%) showed cytoplasmic CM1 positivity. In multivariate analysis, only multiploidy and p53 nuclear positivity emerged as independent prognostic indicators of a poorer outcome. Positivity for p53 was associated with shorter survival in 5-fluorouracil-treated and untreated patients. Therefore, in patients with Dukes B2 colorectal cancer, a biologic profile based on the combined evaluation of DNA multiploidy and p53 status can provide valuable prognostic information, identifying patients to be enrolled in alternative, more aggressive therapeutic trials.

  12. Dissolution of aerosol particles collected from nuclear facility plutonium production process

    International Nuclear Information System (INIS)

    Ning Xu; Martinez, Alex; Schappert, Michael; Montoya, D.P.; Martinez, Patrick; Tandon, Lav

    2016-01-01

    A simple, robust analytical chemistry method has been developed to dissolve plutonium containing particles in a complex matrix. The aerosol particles collected on Marple cascade impactor substrates were shown to be dissolved completely with an acid mixture of 12 M HNO 3 and 0.1 M HF. A pressurized closed vessel acid digestion technique was utilized to heat the samples at 130 deg C for 16 h to facilitate the digestion. The dissolution efficiency for plutonium particles was 99 %. The resulting particle digestate solution was suitable for trace elemental analysis and isotope composition determination, as well as radiochemistry measurements. (author)

  13. Primary Results from the Measurement of Nature Ice Nuclear Particles during 2017 Spring in Beijing, China

    Science.gov (United States)

    Che, Y.; Dang, J.; Fang, W.; Qian, Y.

    2017-12-01

    The ice nuclear particles (INPs) play a critical role in weather modification in mixed-phase clouds (MPCs) because ice can influence the supercooled liquid water content through the Wegener-Bergeron-Findeisen process. The fundamental desire to understand ice nucleation is the same as when such research began in earnest more than 60 years ago while the first cloud seeding activity began and enhanced from the last decade by climate change researches. The primary INPs sources, both from natural and anthropogenic, may be change a lot for decades. The purpose of this paper is to get the new background information of INPs and comparing with historical data. The INPs concentrations were observed twice a day(9:00 am and 14:00 pm) in Beijing from Mar. 20 to Apr. 19, 2017 using the 5 Litters Bigg's mixing cloud chamber. The method, time and sites of the observation are basically the same with the experiment at year 1963, 1995 and 1996. Compared with the previous observations, the observed activation temperature -10° is added, besides the -15°, -20°, -25°, -30°. The results show that the INPs concentrations at the different activation temperatures have good consistency trend as diurnal variation. This is consistent with the observations in 1963, 1995 and 1996. The INPs concentrations in this observation are higher than the result in 1963, but obviously lower than 1995 and 1996. It shows that natural changes and human activities in the past 20 years did not significantly increase the INPs concentration. During the observation period, there were weak precipitations in four days (Mar. 20, Mar. 22, Mar. 23, Mar.24), the INPs concentrations tended to decrease in the intermittent precipitation from Mar. 20 to Mar. 25. This shows that the precipitations have effect on the removal of ice nuclei. The visibility sensor was also synchronized observed in the work. There was clearly an inverse correlation between INPs concentration and visibility with the diurnal variation. The

  14. Detection of special nuclear material from delayed neutron emission induced by a dual-particle monoenergetic source

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, M. [Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Nattress, J.; Jovanovic, I., E-mail: ijov@umich.edu [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2016-06-27

    Detection of unique signatures of special nuclear materials is critical for their interdiction in a variety of nuclear security and nonproliferation scenarios. We report on the observation of delayed neutrons from fission of uranium induced in dual-particle active interrogation based on the {sup 11}B(d,n γ){sup 12}C nuclear reaction. Majority of the fissions are attributed to fast fission induced by the incident quasi-monoenergetic neutrons. A Li-doped glass–polymer composite scintillation neutron detector, which displays excellent neutron/γ discrimination at low energies, was used in the measurements, along with a recoil-based liquid scintillation detector. Time-dependent buildup and decay of delayed neutron emission from {sup 238}U were measured between the interrogating beam pulses and after the interrogating beam was turned off, respectively. Characteristic buildup and decay time profiles were compared to the common parametrization into six delayed neutron groups, finding a good agreement between the measurement and nuclear data. This method is promising for detecting fissile and fissionable materials in cargo scanning applications and can be readily integrated with transmission radiography using low-energy nuclear reaction sources.

  15. High-temperature deformation and processing maps of Zr-4 metal matrix with dispersed coated surrogate nuclear fuel particles

    Science.gov (United States)

    Chen, Jing; Liu, Huiqun; Zhang, Ruiqian; Li, Gang; Yi, Danqing; Lin, Gaoyong; Guo, Zhen; Liu, Shaoqiang

    2018-06-01

    High-temperature compression deformation of a Zr-4 metal matrix with dispersed coated surrogate nuclear fuel particles was investigated at 750 °C-950 °C with a strain rate of 0.01-1.0 s-1 and height reduction of 20%. Scanning electron microscopy was utilized to investigate the influence of the deformation conditions on the microstructure of the composite and damage to the coated surrogate fuel particles. The results indicated that the flow stress of the composite increased with increasing strain rate and decreasing temperature. The true stress-strain curves showed obvious serrated oscillation characteristics. There were stable deformation ranges at the initial deformation stage with low true strain at strain rate 0.01 s-1 for all measured temperatures. Additionally, the coating on the surface of the surrogate nuclear fuel particles was damaged when the Zr-4 matrix was deformed at conditions of high strain rate and low temperature. The deformation stability was obtained from the processing maps and microstructural characterization. The high-temperature deformation activation energy was 354.22, 407.68, and 433.81 kJ/mol at true strains of 0.02, 0.08, and 0.15, respectively. The optimum deformation parameters for the composite were 900-950 °C and 0.01 s-1. These results are expected to provide guidance for subsequent determination of possible hot working processes for this composite.

  16. Effect of fuel particles' size variations on multiplication factor in pebble-bed nuclear reactor

    International Nuclear Information System (INIS)

    Snoj, L.; Ravnik, M.

    2005-01-01

    The pebble-bed reactor (Pbr) spherical fuel element consists of two radial zones: the inner zone, in which the fissile material in form of the so-called TRISO particles is uniformly dispersed in graphite matrix and the outer zone, a shell of pure graphite. A TRISO particle is composed of a fissile kernel (UO 2 ) and several layers of carbon composites. The effect of TRISO particles' size variations and distance between them on PBR multiplication factor is studied using MCNP code. Fuel element is modelled in approximation of a cubical unit cell with periodic boundary condition. The multiplication factor of the fuel element depends on the size of the TRISO particles due to resonance self-shielding effect and on the inter-particle distance due to inter-kernel shadowing. (author)

  17. The radiological significance of beta emitting hot particles released from the Chernobyl nuclear power plant

    International Nuclear Information System (INIS)

    Hofmann, W.; Crawford-Brown, D.J.; Martonen, T.B.

    1988-01-01

    In order to assess radiological hazards associated with inhalation of beta emitting hot particles detected in fall-out from the Chernobyl incident, radiation doses and lung cancer risk are calculated for a hot particle composed entirely of 103 Ru. Lung cancer risk estimates are based upon an initiation-promotion model of carcinogenesis. In the immediate vicinity of a hot particle, calculations indicate that doses may be extremely high, so that all cells are killed and no tumour will arise. At intermediate distances, however, the probability for lung cancer induction exhibits a distinct maximum. Risk enhancement factors, computed relative to a uniform radionuclide distribution of equal activity, are highest for intermediate activities and hot particles moving in the lung. While the risk from inhalation of 103 Ru hot particles might, indeed, exceed that from all other exposure pathways of the Chernobyl fall-out, it still lies within normal fluctuations of radon progeny induced lung cancer risk. (author)

  18. On the evaluation of semiclassical nuclear many-particle many-hole level densities

    International Nuclear Information System (INIS)

    Blin, A.H.; Hiller, B.; Schuck, P.; Yannouleas, C.

    1985-10-01

    An exact general scheme is described to calculate the m-particle n-hole fermion level densities for an arbitrary single particle Hamiltonian taking into account the Pauli exclusion principle. This technique is applied to obtain level densities of the three dimensional isotropic harmonic oscillator semiclassically in the Thomas-Fermi approach. In addition, we study the l-particle l-hole level density of the Woods-Saxon potential. For the harmonic oscillator we analyze the temperature dependence of the linear response function and the influence of pairing correlations on the l-particle l-hole level density. Finally, a Taylor expansion method of the m-particle n-hole level densities is discussed

  19. Workshop Summary: Fundamental Neutron Physics in the United States: An Opportunity in Nuclear, Particle, and Astrophysics for the Next Decade

    International Nuclear Information System (INIS)

    Greene, G.

    2001-01-01

    Low-energy neutrons from reactor and spallation neutron sources have been employed in a wide variety of investigations that shed light on important issues in nuclear, particle, and astrophysics; in the elucidation of quantum mechanics; in the determination of fundamental constants; and in the study of fundamental symmetry violation (Appendix A, Glossary). In many cases, these experiments provide important information that is not otherwise available from accelerator-based nuclear physics facilities or high energy accelerators. An energetic research community in the United States is engaged in ''fundamental'' neutron physics. With exciting recent results, the possibility of new and upgraded sources, and a number of new experimental ideas, there is an important opportunity for outstanding science in the next decade. ''Fundamental'' neutron physics experiments are usually intensity limited. Researchers require the highest flux neutron sources available, which are either high-flux reactors (continuous sources) or spallation neutron sources (pulsed sources). The primary mission of these major facilities is neutron scattering for materials science research. Notwithstanding this condensed matter focus, essentially all neutron scattering facilities have accepted the value of an on-site fundamental physics program and have typically allocated 5 to 10% of their capabilities (i.e., beam lines) toward nuclear and particle physics research activities

  20. The electric potential of particles in interstellar space released from a nuclear waste payload

    Science.gov (United States)

    Williams, A. C.

    1980-01-01

    Mechanisms for charging a grain in the interplanetary medium include: (1) capture of solar wind electrons; (2) capture of solar wind protons; (3) ejection of electrons through the photoelectric effect due to the solar radiation; (4) escape of beta particles from beta emitters in the grain; and (5) escape of alpha particles from alpha emitters in the grain. The potentials on both nonradioactive and radioactive grains are considered with relation to particle size and time, and the distance from the Sun. Numerical results are presented where the waste mix is assumed to be PW-4b.

  1. A cosmic-ray nuclear event with an anomalously strong concentration of energy and particles in the central region

    International Nuclear Information System (INIS)

    Amato, N.M.; Arata, N.; Maldonado, R.H.C.

    1986-01-01

    A cosmic-ray induced nuclear event detected in the emulsion chamber is described. The event consists of 217 shower cores with ΣEγ = 1,275 TeV. In log scale, energy and particles are emitted most densely at the small lateral distance corresponding to 0.5 mm; 77 % of the total energy and 61 % of the total multiplicity are inside the radius of 0.65 cm. The shower cores in the central region show exponential-type energy distribution and non-isotropic azimuthal distribution. This event indicates a possibility that phenomena of large transverse momentum could happen to produce a strong concentration of energy and particles in the very forward direction. (Authors) [pt

  2. Optimizing the dynamic response of the H.B. Robinson nuclear plant using multiobjective particle swarm optimization

    International Nuclear Information System (INIS)

    Elsays, Mostafa A.; Naguib Aly, M.; Badawi, Alya A.

    2009-01-01

    In this paper, the Particle Swarm Optimization (PSO) algorithm is modified to deal with Multiobjective Optimization Problems (MOPs). A mathematical model for predicting the dynamic response of the H. B. Robinson nuclear power plant, which represents an Initial Value Problem (IVP) of Ordinary Differential Equations (ODEs), is solved using Runge-Kutta formula. The resulted data values are represented as a system of nonlinear algebraic equations by interpolation schemes for data fitting. This system of fitted nonlinear algebraic equations represents a nonlinear multiobjective optimization problem. A Multiobjective Particle Swarm Optimizer (MOPSO) which is based on the Pareto optimality concept is developed and applied to maximize the above mentioned problem. Results show that MOPSO efficiently cope with the problem and finds multiple Pareto optimal solutions. (orig.)

  3. A cosmic-ray nuclear event with an anomalously strong concentration of energy and particles in the central region

    International Nuclear Information System (INIS)

    Amato, N.M.; Arata, N.; Maldonado, R.H.C.

    1987-01-01

    A cosmic-ray-induced nuclear event detected in an emulsion chamber is described. The event consist of 217 shower cores with ΣEγ=1.275 TeV. In a logarithmic scale, energy and particles are emitted most densely at the small lateral distance corresponding to 0.5 mm; 77% of the total energy and 61% of the total multiplicity are inside a radius of 0.65 cm. The shower cores in the central region show exponential-type energy distribution and nonisotropic azimuthal distribution

  4. Nuclear density distributions of 40,42,44,48Ca from elastic scattering of 104 MeV alpha particles

    International Nuclear Information System (INIS)

    Gils, H.J.; Friedman, E.; Majka, Z.

    1979-12-01

    The elastic scattering of 104 MeV α particles from 40 , 42 , 44 , 48 Ca has been analyzed by a single folding model with a density dependent effective interaction. Nuclear density distributions have been extracted using various descriptions including Fourier-Bessel series which distinctly reduces the model dependence of the results and enables realistic estimates of errors. Differences of the density shapes of the Ca-isotopes are well determined showing evidence for a neutron skin in 48 Ca. The resulting root mean square radii are compared to the results obtained from other methods. The sensitivity and limitations of various methods are discussed. (orig.) 891 KBE/orig. 892 BRE

  5. The Polyakov, Nambu and Jona-Lasinio model and its applications to describe the sub-nuclear particles

    International Nuclear Information System (INIS)

    Blanquier, E.

    2013-01-01

    To study the high energy nuclear physics and the associated phenomenon, as the quark-gluon plasma / hadronic matter phase transition, the Nambu and Jona-Lasinio model (NJL) appears as an interesting alternative to the Quantum Chromodynamics, not solvable at the considered energies. Indeed, the NJL model allows the description of quarks physics, at finite temperatures and densities. Furthermore, in order to try to correct a limitation of the NJL model, i.e. the absence of confinement, it was proposed a coupling of the quarks/antiquarks to a Polyakov loop, forming the PNJL model. The objective of this thesis is to see the possibilities offered by the NJL and PNJL models, to describe relevant sub-nuclear particles (quarks, mesons, diquarks and baryons), to study their interactions, and to proceed to a dynamical study involving these particles. After a recall of the useful tools, we modeled the u, d, s effective quarks and the mesons. Then, we described the baryons as quarks-diquarks bound states. A part of the work concerned the calculations of the cross-sections associated to the possible reactions implying these particles. Then, we incorporated these results in a computer code, in order to study the cooling of a quarks/antiquarks plasma and its hadronization. In this study, each particle evolves in a system in which the temperature and the densities are local parameters. We have two types of interactions: one due to the collisions, and the other is a remote interaction, notably between quarks. Finally, we studied the properties of our approach: qualities, limitations, and possible evolutions. (author)

  6. Nuclear and mitochondrial phylogeography of the European fire-bellied toads Bombina bombina and Bombina variegata supports their independent histories

    Czech Academy of Sciences Publication Activity Database

    Fijarczyk, A.; Nadachowska, K.; Hofman, S.; Litvinchuk, S.N.; Babik, W.; Stuglik, M.; Gollmann, G.; Choleva, Lukáš; Cogalniceanu, D.; Vukov, T.; Dzukic, G.; Szymura, J. M.

    2011-01-01

    Roč. 20, č. 16 (2011), s. 3381-3398 ISSN 0962-1083 Institutional research plan: CEZ:AV0Z50450515 Keywords : Bombina * isolation with migration * nuclear and mitochondrial markers Subject RIV: EH - Ecology, Behaviour Impact factor: 5.522, year: 2011

  7. Particle Swarm Optimization applied to combinatorial problem aiming the fuel recharge problem solution in a nuclear reactor; Particle swarm optimization aplicado ao problema combinatorio com vistas a solucao do problema de recarga em um reator nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Meneses, Anderson Alvarenga de Moura; Schirru, Roberto [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear]. E-mail: ameneses@con.ufrj.br; schirru@lmp.ufrj.br

    2005-07-01

    This work focuses on the usage the Artificial Intelligence technique Particle Swarm Optimization (PSO) to optimize the fuel recharge at a nuclear reactor. This is a combinatorial problem, in which the search of the best feasible solution is done by minimizing a specific objective function. However, in this first moment it is possible to compare the fuel recharge problem with the Traveling Salesman Problem (TSP), since both of them are combinatorial, with one advantage: the evaluation of the TSP objective function is much more simple. Thus, the proposed methods have been applied to two TSPs: Oliver 30 and Rykel 48. In 1995, KENNEDY and EBERHART presented the PSO technique to optimize non-linear continued functions. Recently some PSO models for discrete search spaces have been developed for combinatorial optimization. Although all of them having different formulation from the ones presented here. In this paper, we use the PSO theory associated with to the Random Keys (RK)model, used in some optimizations with Genetic Algorithms. The Particle Swarm Optimization with Random Keys (PSORK) results from this association, which combines PSO and RK. The adaptations and changings in the PSO aim to allow the usage of the PSO at the nuclear fuel recharge. This work shows the PSORK being applied to the proposed combinatorial problem and the obtained results. (author)

  8. Evolution of etched nuclear track profiles of alpha particles in CR-39 by atomic force microscopy

    International Nuclear Information System (INIS)

    Félix-Bautista, R.; Hernández-Hernández, C.; Zendejas-Leal, B.E.; Fragoso, R.; Golzarri, J.I.; Vázquez-López, C.; Espinosa, G.

    2013-01-01

    A series of atomic force microscopy (AFM) images of etched nuclear tracks has been obtained and used to calculate the nuclear track registration sensitivity parameter V(x) = Vt(x)/Vb. Due to the AFM limitations the samples were irradiated normally to the surface, and with energies attenuated in order to include the Bragg peak region in the AFM piezo-scanner z movement range. The simulation of the track profile evolution was then obtained. The different stages of etched nuclear track profiles were rendered. - Highlights: ► Using AFM we reach that Bragg peak region of etched tracks in CR-39. ► The etched track sensitivity V was calculated by data obtained by AFM. ► The evolucion of etched nuclear tracks was simulated by data achieved by AFM

  9. Accident-generated radioactive particle source term development for consequence assessment of nuclear fuel cycle facilities

    International Nuclear Information System (INIS)

    Sutter, S.L.; Ballinger, M.Y.; Halverson, M.A.; Mishima, J.

    1983-04-01

    Consequences of nuclear fuel cycle facility accidents can be evaluated using aerosol release factors developed at Pacific Northwest Laboratory. These experimentally determined factors are compiled and consequence assessment methods are discussed. Release factors can be used to estimate the fraction of material initially made airborne by postulated accident scenarios. These release fractions in turn can be used in models to estimate downwind contamination levels as required for safety assessments of nuclear fuel cycle facilities. 20 references, 4 tables

  10. High-speed particle tracking in nuclear emulsion by last-generation automatic microscopes

    International Nuclear Information System (INIS)

    Armenise, N.; De Serio, M.; Ieva, M.; Muciaccia, M.T.; Pastore, A.; Simone, S.; Damet, J.; Kreslo, I.; Savvinov, N.; Waelchli, T.; Consiglio, L.; Cozzi, M.; Di Ferdinando, D.; Esposito, L.S.; Giacomelli, G.; Giorgini, M.; Mandrioli, G.; Patrizii, L.; Sioli, M.; Sirri, G.; Arrabito, L.; Laktineh, I.; Royole-Degieux, P.; Buontempo, S.; D'Ambrosio, N.; De Lellis, G.; De Rosa, G.; Di Capua, F.; Coppola, D.; Formisano, F.; Marotta, A.; Migliozzi, P.; Pistillo, C.; Scotto Lavina, L.; Sorrentino, G.; Strolin, P.; Tioukov, V.; Juget, F.; Hauger, M.; Rosa, G.; Barbuto, E.; Bozza, C.; Grella, G.; Romano, G.; Sirignano, C.

    2005-01-01

    The technique of nuclear emulsions for high-energy physics experiments is being revived, thanks to the remarkable progress in measurement automation achieved in the past years. The present paper describes the features and performances of the European Scanning System, a last-generation automatic microscope working at a scanning speed of 20cm 2 /h. The system has been developed in the framework of the OPERA experiment, designed to unambigously detect ν μ ->ν τ oscillations in nuclear emulsions

  11. A study of the fluorescence of the rare gases excited by nuclear particles. Use of the principle for the detection of nuclear radiation by scintillation

    International Nuclear Information System (INIS)

    Koch, L.

    1959-12-01

    In the first part is studied the properties of atoms excited by the passage of α particles through the various rare gases at atmospheric pressure. A spectral analysis of the emitted light showed that certain impurities play an important part in producing the fluorescence, and it has led to the conclusion that the light emission contains at least two components - one very short - lived due to the direct deexcitation of the rare gas, the other relatively slower due to the energy transfers to the impurity. The measurement of the life-time of the excited states has confirmed this foregoing hypothesis, the rapid part of the impulse is extremely short: less than 2,25.10 -9 s in the case of xenon; the slower part has a life-time depending directly on the nitrogen concentration, nitrogen being the impurity giving the largest effect in all cases. The study of rare gases under the influence of an electric field has made it possible to show that the amount of light produced by an α particle can be multiplied (by 60, for example, in a field of 600 V:cm) so that the luminescent efficiency is greater than in the case of INaTI. In the second part the characteristics of the rare gases acting as scintillators is examined, the most important property being the absence of fluorescence saturation when the intensity of the excitation incident on the gas is very large. This, together with the very short time of scintillation has made it possible to study a certain number of nuclear physical applications (heavy particle energy-measurements, kinetic studies on nuclear reactors, neutron spectroscopy). (author) [fr

  12. Proposal of guidelines for structuring an independent regulation body for the Brazilian nuclear sector; Proposta de diretrizes para estruturacao de um orgao de regulacao independente para o setor nuclear brasileiro

    Energy Technology Data Exchange (ETDEWEB)

    Nicoll Junior, Ricardo

    2016-07-01

    Regulatory bodies are responsible for regulation in various sectors of society. In Brazil, they work in various areas for the development of the country and have as main objective the social, economic and national development. The progress of new technologies in the nuclear field and their commercialization underscores the need for regulation according to international safety standards. The present research searches through an extensive review of the literature identify the international guidelines for regulatory bodies and make a comparative analysis between Brazil and five countries that have independent regulatory bodies in the nuclear sector. The purpose of the work is to contribute to the Brazilian public sectors, with an evaluation of the country's regulation in the perception of specialists and propose guidelines for the structuring of an independent regulatory body, respecting international agreements and the legislation in force in the country. (author)

  13. Nuclear TK1 expression is an independent prognostic factor for survival in pre-malignant and malignant lesions of the cervix

    International Nuclear Information System (INIS)

    Chen, Gang; He, Cheng; Li, Ling; Lin, An; Zheng, Xiongwei; He, Ellen; Skog, Sven

    2013-01-01

    Thymidine kinase 1 (TK1) is a proliferation biomarker that has been found useful for prognostication in cancer patients. Here we investigate for the first time the use of TK1 expression as a prognostic factor for patients with premalignant and malignant lesions of the uterine cervix. TK1 expression was determined by immunohistochemistry in cervical lesions (cervical intraepithelial neoplasia (CIN), n = 216; invasive cervical carcinoma, n = 84). TK1 and Ki-67 expressions and pathological/FIGO stages and age were correlated with 5-year survival by Kaplan-Meier, log rank and COX hazard uni- and multivariate analyses. TK1 labeling index (LI) was significantly correlated with CIN grades and invasive cervical carcinoma stages, while TK1 labeling intensity was only correlated to CIN grades. TK1 LI was significantly higher compared with Ki-67 LI. TK1 LI correlated significantly to 5-year survival in patients with invasive cervical carcinoma, particularly nuclear TK1 LI. In a multivariate analysis, nuclear TK1 expression was independent prognostic factor in patients with in situ/invasive cervical carcinoma or in invasive cervical carcinoma alone. Interestingly, in invasive cervical carcinoma patients with advanced tumors, nuclear TK1 expression could identify patients with significantly better survival rates (80%), while Ki-67 could not. Nuclear TK1 expression in early grade CIN predicts risk for progression to malignancy. Nuclear TK1 expression is also a prognostic factor for treatment outcome, particularly in patients with advanced cervical carcinomas. Nuclear TK1 expression is more useful than Ki-67 and pathological/FIGO stages

  14. The nuclear import of the human T lymphotropic virus type I (HTLV-1) tax protein is carrier- and energy-independent.

    Science.gov (United States)

    Tsuji, Takahiro; Sheehy, Noreen; Gautier, Virginie W; Hayakawa, Hitoshi; Sawa, Hirofumi; Hall, William W

    2007-05-04

    HTLV-1 is the etiologic agent of the adult T cell leukemialymphoma (ATLL). The viral regulatory protein Tax plays a central role in leukemogenesis as a transcriptional transactivator of both viral and cellular gene expression, and this requires Tax activity in both the cytoplasm and the nucleus. In the present study, we have investigated the mechanisms involved in the nuclear localization of Tax. Employing a GFP fusion expression system and a range of Tax mutants, we could confirm that the N-terminal 60 amino acids, and specifically residues within the zinc finger motif in this region, are important for nuclear localization. Using an in vitro nuclear import assay, it could be demonstrated that the transportation of Tax to the nucleus required neither energy nor carrier proteins. Specific and direct binding between Tax and p62, a nucleoporin with which the importin beta family of proteins have been known to interact was also observed. The nuclear import activity of wild type Tax and its mutants and their binding affinity for p62 were also clearly correlated, suggesting that the entry of Tax into the nucleus involves a direct interaction with nucleoporins within the nuclear pore complex (NPC). The nuclear export of Tax was also shown to be carrier independent. It could be also demonstrated that Tax it self may have a carrier function and that the NF-kappaB subunit p65 could be imported into the nucleus by Tax. These studies suggest that Tax could alter the nucleocytoplasmic distribution of cellular proteins, and this could contribute to the deregulation of cellular processes observed in HTLV-1 infection.

  15. Angiogenin-induced protein kinase B/Akt activation is necessary for angiogenesis but is independent of nuclear translocation of angiogenin in HUVE cells

    International Nuclear Information System (INIS)

    Kim, Hye-Mi; Kang, Dong-Ku; Kim, Hak Yong; Kang, Sang Sun; Chang, Soo-Ik

    2007-01-01

    Angiogenin, a potent angiogenic factor, binds to endothelial cells and is endocytosed and rapidly translocated to and concentrated in the nucleolus where it binds to DNA. In this study, we report that angiogenin induces transient phosphorylation of protein kinase B/Akt in cultured human umbilical vein endothelial (HUVE) cells. LY294002 inhibits the angiogenin-induced protein kinase B/Akt activation and also angiogenin-induced cell migration in vitro as well as angiogenesis in chick embryo chorioallantoic membrane in vivo without affecting nuclear translocation of angiogenin in HUVE cells. These results suggest that cross-talk between angiogenin and protein kinase B/Akt signaling pathways is essential for angiogenin-induced angiogenesis in vitro and in vivo, and that angiogenin-induced PKB/Akt activation is independent of nuclear translocation of angiogenin in HUVE cells

  16. DNA-histone complexes as ligands amplify cell penetration and nuclear targeting of anti-DNA antibodies via energy-independent mechanisms.

    Science.gov (United States)

    Zannikou, Markella; Bellou, Sofia; Eliades, Petros; Hatzioannou, Aikaterini; Mantzaris, Michael D; Carayanniotis, George; Avrameas, Stratis; Lymberi, Peggy

    2016-01-01

    We have generated three monoclonal cell-penetrating antibodies (CPAbs) from a non-immunized lupus-prone (NZB × NZW)F1 mouse that exhibited high anti-DNA serum titres. These CPAbs are polyreactive because they bind to DNA and other cellular components, and localize mainly in the nucleus of HeLa cells, albeit with a distinct nuclear labelling profile. Herein, we have examined whether DNA-histone complexes (DHC) binding to CPAbs, before cell entry, could modify the cell penetration of CPAbs or their nuclear staining properties. By applying confocal microscopy and image analysis, we found that extracellular binding of purified CPAbs to DHC significantly enhanced their subsequent cell-entry, both in terms of percentages of positively labelled cells and fluorescence intensity (internalized CPAb amount), whereas there was a variable effect on their nuclear staining profile. Internalization of CPAbs, either alone or bound to DHC, remained unaltered after the addition of endocytosis-specific inhibitors at 37° or assay performance at 4°, suggesting the involvement of energy-independent mechanisms in the internalization process. These findings assign to CPAbs a more complex pathogenetic role in systemic lupus erythematosus where both CPAbs and nuclear components are abundant. © 2015 John Wiley & Sons Ltd.

  17. Independent Confirmatory Survey Report for the University of Arizona Nuclear Reactor Laboratory, Tucson, Arizona DCN:2051-SR-01-0

    International Nuclear Information System (INIS)

    Altic, Nick A.

    2011-01-01

    The University of Arizona (University) research reactor is a TRIGA swimming pool type reactor designed by General Atomics and constructed at the University in 1958. The reactor first went into operation in December of 1958 under U.S. Nuclear Regulatory Commission (NRC) license R-52 until final shut down on May 18, 2010. Initial site characterization activities were conducted in February 2009 during ongoing reactor operations to assess the radiological status of the Nuclear Reactor Laboratory (NRL) excluding the reactor tank, associated components, and operating systems. Additional post-shutdown characterization activities were performed to complete characterization activities as well as verify assumptions made in the Decommissioning Plan (DP) that were based on a separate activation analysis (ESI 2009 and WMG 2009). Final status survey (FSS) activities began shortly after the issuance of the FSS plan in May 2011. The contractor completed measurement and sampling activities during the week of August 29, 2011.

  18. Nuclear energy - Reference beta-particle radiation - Part 2: Calibration fundamentals related to basic quantities characterizing the radiation field

    International Nuclear Information System (INIS)

    2004-01-01

    ISO 6980 consists of the following parts, under the general title Nuclear energy - Reference beta-particle radiation: Part 1: Method of production; Part 2: Calibration fundamentals related to basic quantities characterizing the radiation field; Part 3: Calibration of area and personal dosimeters and determination of their response as a function of energy and angle of incidence. This part 2 of ISO 6980 specifies methods for the measurement of the directional absorbed-dose rate in a tissue-equivalent slab phantom in the ISO 6980 reference beta-particle radiation fields. The energy range of the beta-particle-emitting isotopes covered by these reference radiations is 0.066 to 3.54 MeV (maximum energy). Radiation energies outside this range are beyond the scope of this standard. While measurements in a reference geometry (depth of 0.07 mm at perpendicular incidence in a tissue-equivalent slab phantom) with a reference class extrapolation chamber are dealt with in detail, the use of other measurement systems and measurements in other geometries are also described, although in less detail. The ambient dose equivalent, H*(10) as used for area monitoring of strongly penetrating radiation, is not an appropriate quantity for any beta radiation, even for that penetrating a 10 mm thick layer of ICRU tissue (i.e. E max > 2 MeV). If adequate protection is provided at 0.07 mm, only rarely will one be concerned with other depths, for example 3 mm. This document is geared towards organizations wishing to establish reference-class dosimetry capabilities for beta particles, and serves as a guide to the performance of dosimetry with the reference class extrapolation chamber for beta-particle dosimetry in other fields. Guidance is also provided on the statement of measurement uncertainties

  19. Caesium-rich micro-particles: A window into the meltdown events at the Fukushima Daiichi Nuclear Power Plant

    Science.gov (United States)

    Furuki, Genki; Imoto, Junpei; Ochiai, Asumi; Yamasaki, Shinya; Nanba, Kenji; Ohnuki, Toshihiko; Grambow, Bernd; Ewing, Rodney C.; Utsunomiya, Satoshi

    2017-02-01

    The nuclear disaster at the Fukushima Daiichi Nuclear Power Plant (FDNPP) in March 2011 caused partial meltdowns of three reactors. During the meltdowns, a type of condensed particle, a caesium-rich micro-particle (CsMP), formed inside the reactors via unknown processes. Here we report the chemical and physical processes of CsMP formation inside the reactors during the meltdowns based on atomic-resolution electron microscopy of CsMPs discovered near the FDNPP. All of the CsMPs (with sizes of 2.0-3.4 μm) comprise SiO2 glass matrices and ~10-nm-sized Zn-Fe-oxide nanoparticles associated with a wide range of Cs concentrations (1.1-19 wt% Cs as Cs2O). Trace amounts of U are also associated with the Zn-Fe oxides. The nano-texture in the CsMPs records multiple reaction-process steps during meltdown in the severe FDNPP accident: Melted fuel (molten core)-concrete interactions (MCCIs), incorporating various airborne fission product nanoparticles, including CsOH and CsCl, proceeded via SiO2 condensation over aggregates of Zn-Fe oxide nanoparticles originating from the failure of the reactor pressure vessels. Still, CsMPs provide a mechanism by which volatile and low-volatility radionuclides such as U can reach the environment and should be considered in the migration model of Cs and radionuclides in the current environment surrounding the FDNPP.

  20. Particle Swarm Optimization applied to combinatorial problem aiming the fuel recharge problem solution in a nuclear reactor

    International Nuclear Information System (INIS)

    Meneses, Anderson Alvarenga de Moura; Schirru, Roberto

    2005-01-01

    This work focuses on the usage the Artificial Intelligence technique Particle Swarm Optimization (PSO) to optimize the fuel recharge at a nuclear reactor. This is a combinatorial problem, in which the search of the best feasible solution is done by minimizing a specific objective function. However, in this first moment it is possible to compare the fuel recharge problem with the Traveling Salesman Problem (TSP), since both of them are combinatorial, with one advantage: the evaluation of the TSP objective function is much more simple. Thus, the proposed methods have been applied to two TSPs: Oliver 30 and Rykel 48. In 1995, KENNEDY and EBERHART presented the PSO technique to optimize non-linear continued functions. Recently some PSO models for discrete search spaces have been developed for combinatorial optimization. Although all of them having different formulation from the ones presented here. In this paper, we use the PSO theory associated with to the Random Keys (RK)model, used in some optimizations with Genetic Algorithms. The Particle Swarm Optimization with Random Keys (PSORK) results from this association, which combines PSO and RK. The adaptations and changings in the PSO aim to allow the usage of the PSO at the nuclear fuel recharge. This work shows the PSORK being applied to the proposed combinatorial problem and the obtained results. (author)

  1. Final report of the IAEA advisory group meeting on accelerator-based nuclear analytical techniques for characterization and source identification of aerosol particles

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    The field of aerosol characterization and source identification covers a wide range of scientific and technical activities in many institutions, in both developed and developing countries. This field includes research and applications on urban air pollution, source apportionment of suspended particulate matter, radioactive aerosol particles, organic compounds carried on particulate matter, elemental characterization of particles, and other areas. The subject of this AGM focused on the use of accelerator-based nuclear analytical techniques for determination of elemental composition of particles (by either bulk or single particle analysis) and the use of accumulated knowledge for source identification.

  2. Final report of the IAEA advisory group meeting on accelerator-based nuclear analytical techniques for characterization and source identification of aerosol particles

    International Nuclear Information System (INIS)

    1995-01-01

    The field of aerosol characterization and source identification covers a wide range of scientific and technical activities in many institutions, in both developed and developing countries. This field includes research and applications on urban air pollution, source apportionment of suspended particulate matter, radioactive aerosol particles, organic compounds carried on particulate matter, elemental characterization of particles, and other areas. The subject of this AGM focused on the use of accelerator-based nuclear analytical techniques for determination of elemental composition of particles (by either bulk or single particle analysis) and the use of accumulated knowledge for source identification

  3. Identification of charged particles by etching the solid state nuclear track detectors in successive intervals

    International Nuclear Information System (INIS)

    Randhawa, G.S.; Virk, H.S.

    1997-01-01

    The suitability of the method of charged particle identification by etching the samples in successive intervals developed by Grabez et al. has been checked in CR-39 exposed to heavy ions 238 U, 208 Pb, 197 Au and 132 Xe in the interval 11.0 to 17.0 MeV/u. A similar study has been made on soda glass detectors irradiated by 238 U, 132 Xe, 56 Fe and 48 Ti ions having energy 4.0 to 6.0 MeV/u. It is concluded that this method of particle identification can be used successfully in CR-39 and soda glass detectors. (author)

  4. Quantum chaos in nuclear single-particle motion and damping of giant resonances

    International Nuclear Information System (INIS)

    Pal, Santanu; Mukhopadhyay, Tapan

    1995-01-01

    The spectral statistics of single particle motion in deformed cavities with axial symmetry are presented. The single particle motion in the cavities considered are non-integrable and the systematics of the fluctuation measures of the spectra reveal a transition from regular to chaotic regime in the corresponding classical systems. Quantitative estimate of the degree of chaos enables us to introduce a correction factor to the one-body wall formula for the damping widths of isoscalar giant resonances. The damping widths calculated with this correction factor give much better agreement with experimental values than earlier calculations of one-body damping widths. (author). 21 refs., 5 figs

  5. Improved single particle potential for transport model simulations of nuclear reactions induced by rare isotope beams

    International Nuclear Information System (INIS)

    Xu Chang; Li Baoan

    2010-01-01

    Taking into account more accurately the isospin dependence of nucleon-nucleon interactions in the in-medium many-body force term of the Gogny effective interaction, new expressions for the single-nucleon potential and the symmetry energy are derived. Effects of both the spin (isospin) and the density dependence of nuclear effective interactions on the symmetry potential and the symmetry energy are examined. It is shown that they both play a crucial role in determining the symmetry potential and the symmetry energy at suprasaturation densities. The improved single-nucleon potential will be useful for more accurate simulation of nuclear reactions induced by rare-isotope beams within transport models.

  6. Nuclear shape transitions and some properties of aligned-particle configurations at high spin

    International Nuclear Information System (INIS)

    Koo, T.L.; Chowdhury, P.; Emling, H.

    1982-01-01

    Two topics are addressed in this paper. First, we discuss the variation of shapes with spin and neutron number for nuclei in the N approx. = 88 transitional region. Second, we present comments on the feeding times of very high spin single-particle yrast states

  7. Effects of particle-number-projection on nuclear moment of intertia

    International Nuclear Information System (INIS)

    Rozmej, P.

    1976-01-01

    The formalism of the moment of inertia in cranking model and BCS theory has been extended for the partially particle-number-projected BCS wave functions. The ground state moments of inertia obtained by this method are a little greater than those calculated by BCS method. A smooth growth of the moments of inertia for diminishing pairing strength constant has been obtained. (author)

  8. Nuclear molecular halo: the ubiquitous occurrence of van der Waals molecular states near threshold in molecular, nuclear and particle physics

    International Nuclear Information System (INIS)

    Gai, Moshe

    1999-01-01

    The observation of large E1 strength near threshold in the electromagnetic dissociation of 11 Li poses a fundamental question: Is the large E1 strength due to the threshold or is it due to a low lying E1 state? Such molecular cluster states were observed in 18 O and in several nuclei near the drip line. We discuss the nature of the threshold effect as well as review the situation in Molecular (and Particle Physics) where such Molecular States are observed near the dissociation limit. We suggest that the situation in 11 Li is reminiscent of the argon-benzene molecule where the argon atom is loosely bound by a polarization (van der Waals) mechanism and thus leads to a very extended object lying near the dissociation limit. Such states are also suggested to dominate the structure of mesons [α 0 (980), f 0 (975)] and baryons [λ(1405)] with proposed Kaon molecular structure (Dalitz) near threshold. The inspection of such states throughout Physics allows us to gain insight into this phenomenon and suggest that a new collective Molecular Dipole Degree of Freedom plays a major role in the structure of hadrons (halo nuclei, mesons and baryons), and that quantitative tools such as the E1 Molecular Sum Rule are useful for elucidating the nature of the observed low lying E1 strength in halo nuclei. (author)

  9. Reactions of charged and neutral recoil particles following nuclear transformations. Progress report No. 10

    International Nuclear Information System (INIS)

    Ache, H.J.

    1976-09-01

    The status of the following programs is reported: study of the stereochemistry of halogen atom reactions produced via (n,γ) nuclear reactions with diastereomeric molecules in the condensed phase; decay-induced labelling of compounds of biochemical interest; and chemistry of positronium

  10. Observation of strong azimuthal asymmetry between slow and fast particles from high energy nuclear collisions

    International Nuclear Information System (INIS)

    Gustafsson, H.A.; Gutbrod, H.H.; Kolb, B.; Loehner, H.; Ludewigt, B.; Poskanzer, A.M.; Renner, T.; Riedesel, H.; Ritter, H.G.; Siemiarczuk, T.; Stepaniak, J.; Warwick, A.; Wieman, H.

    1984-10-01

    Evidence is presented for the strong azimuthal asymmetry between slow and fast fragments in nuclear collisions in the energy interval of 0.4 to 1 GeV per nucleon. The asymmetry gets stronger when incident energy and impact parameter decrease. The results on the A dependence of the azimuthal asymmetry are also presented. (orig.)

  11. Nuclear fusion-independent smooth muscle differentiation of human adipose-derived stem cells induced by a smooth muscle environment.

    Science.gov (United States)

    Zhang, Rong; Jack, Gregory S; Rao, Nagesh; Zuk, Patricia; Ignarro, Louis J; Wu, Benjamin; Rodríguez, Larissa V

    2012-03-01

    Human adipose-derived stem cells hASC have been isolated and were shown to have multilineage differentiation capacity. Although both plasticity and cell fusion have been suggested as mechanisms for cell differentiation in vivo, the effect of the local in vivo environment on the differentiation of adipose-derived stem cells has not been evaluated. We previously reported the in vitro capacity of smooth muscle differentiation of these cells. In this study, we evaluate the effect of an in vivo smooth muscle environment in the differentiation of hASC. We studied this by two experimental designs: (a) in vivo evaluation of smooth muscle differentiation of hASC injected into a smooth muscle environment and (b) in vitro evaluation of smooth muscle differentiation capacity of hASC exposed to bladder smooth muscle cells. Our results indicate a time-dependent differentiation of hASC into mature smooth muscle cells when these cells are injected into the smooth musculature of the urinary bladder. Similar findings were seen when the cells were cocultured in vitro with primary bladder smooth muscle cells. Chromosomal analysis demonstrated that microenvironment cues rather than nuclear fusion are responsible for this differentiation. We conclude that cell plasticity is present in hASCs, and their differentiation is accomplished in the absence of nuclear fusion. Copyright © 2011 AlphaMed Press.

  12. Independent Verification and Validation Of SAPHIRE 8 Software Requirements Project Number: N6423 U.S. Nuclear Regulatory Commission

    Energy Technology Data Exchange (ETDEWEB)

    Kent Norris

    2009-09-01

    The purpose of the Independent Verification and Validation (IV&V) role in the evaluation of the SAPHIRE requirements definition is to assess the activities that results in the specification, documentation, and review of the requirements that the software product must satisfy, including functionality, performance, design constraints, attributes and external interfaces. The IV&V team began this endeavor after the software engineering and software development of SAPHIRE had already been in production. IV&V reviewed the requirements specified in the NRC Form 189s to verify these requirements were included in SAPHIRE’s Software Verification and Validation Plan (SVVP).

  13. Repair pathways independent of the Fanconi anemia nuclear core complex play a predominant role in mitigating formaldehyde-induced DNA damage

    International Nuclear Information System (INIS)

    Noda, Taichi; Takahashi, Akihisa; Kondo, Natsuko; Mori, Eiichiro; Okamoto, Noritomo; Nakagawa, Yosuke; Ohnishi, Ken; Zdzienicka, Malgorzata Z.; Thompson, Larry H.; Helleday, Thomas; Asada, Hideo

    2011-01-01

    The role of the Fanconi anemia (FA) repair pathway for DNA damage induced by formaldehyde was examined in the work described here. The following cell types were used: mouse embryonic fibroblast cell lines FANCA -/- , FANCC -/- , FANCA -/- C -/- , FANCD2 -/- and their parental cells, the Chinese hamster cell lines FANCD1 mutant (mt), FANCGmt, their revertant cells, and the corresponding wild-type (wt) cells. Cell survival rates were determined with colony formation assays after formaldehyde treatment. DNA double strand breaks (DSBs) were detected with an immunocytochemical γH2AX-staining assay. Although the sensitivity of FANCA -/- , FANCC -/- and FANCA -/- C -/- cells to formaldehyde was comparable to that of proficient cells, FANCD1mt, FANCGmt and FANCD2 -/- cells were more sensitive to formaldehyde than the corresponding proficient cells. It was found that homologous recombination (HR) repair was induced by formaldehyde. In addition, γH2AX foci in FANCD1mt cells persisted for longer times than in FANCD1wt cells. These findings suggest that formaldehyde-induced DSBs are repaired by HR through the FA repair pathway which is independent of the FA nuclear core complex. -- Research highlights: → We examined to clarify the repair pathways of formaldehyde-induced DNA damage. Formaldehyde induces DNA double strand breaks (DSBs). → DSBs are repaired through the Fanconi anemia (FA) repair pathway. → This pathway is independent of the FA nuclear core complex. → We also found that homologous recombination repair was induced by formaldehyde.

  14. The particle swarm optimization algorithm applied to nuclear systems surveillance test planning; Otimizacao aplicada ao planejamento de politicas de testes em sistemas nucleares por enxame de particulas

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, Newton Norat

    2006-12-15

    This work shows a new approach to solve availability maximization problems in electromechanical systems, under periodic preventive scheduled tests. This approach uses a new Optimization tool called PSO developed by Kennedy and Eberhart (2001), Particle Swarm Optimization, integrated with probabilistic safety analysis model. Two maintenance optimization problems are solved by the proposed technique, the first one is a hypothetical electromechanical configuration and the second one is a real case from a nuclear power plant (Emergency Diesel Generators). For both problem PSO is compared to a genetic algorithm (GA). In the experiments made, PSO was able to obtain results comparable or even slightly better than those obtained b GA. Therefore, the PSO algorithm is simpler and its convergence is faster, indicating that PSO is a good alternative for solving such kind of problems. (author)

  15. Production of medically useful bromine isotopes via alpha-particle induced nuclear reactions

    Science.gov (United States)

    Breunig, Katharina; Scholten, Bernhard; Spahn, Ingo; Hermanne, Alex; Spellerberg, Stefan; Coenen, Heinz H.; Neumaier, Bernd

    2017-09-01

    The cross sections of α-particle induced reactions on arsenic leading to the formation of 76,77,78Br were measured from their respective thresholds up to 37 MeV. Thin sediments of elemental arsenic powder were irradiated together with Al degrader and Cu monitor foils using the established stacked-foil technique. For determination of the effective α-particle energies and of the effective beam current through the stacks the cross-section ratios of the monitor nuclides 67Ga/66Ga were used. This should help resolve discrepancies in existing literature data. Comparison of the data with the available excitation functions shows some slight energy shifts as well as some differences in curve shapes. The calculated thick target yields indicate, that 77Br can be produced in the energy range Eα = 25 → 17 MeV free of isotopic impurities in quantities sufficient for medical application.

  16. Production of medically useful bromine isotopes via alpha-particle induced nuclear reactions

    Directory of Open Access Journals (Sweden)

    Breunig Katharina

    2017-01-01

    Full Text Available The cross sections of α-particle induced reactions on arsenic leading to the formation of 76,77,78Br were measured from their respective thresholds up to 37 MeV. Thin sediments of elemental arsenic powder were irradiated together with Al degrader and Cu monitor foils using the established stacked-foil technique. For determination of the effective α-particle energies and of the effective beam current through the stacks the cross-section ratios of the monitor nuclides 67Ga/66Ga were used. This should help resolve discrepancies in existing literature data. Comparison of the data with the available excitation functions shows some slight energy shifts as well as some differences in curve shapes. The calculated thick target yields indicate, that 77Br can be produced in the energy range Eα = 25 → 17 MeV free of isotopic impurities in quantities sufficient for medical application.

  17. The use of nuclear muprobe techniques to study the chemistry of lacustrine sediments and particles

    Science.gov (United States)

    Grime, G. W.; Davison, W.

    1993-05-01

    The Oxford SPM has been used in two novel studies of lake chemistry: (a) The distribution of dissolved iron in sediment pore waters close to the sediment/water interface has been measured using the novel technique of diffusive equilibration in a thin film (DET). In this technique, which has a spatial resolution of O stoichiometry of single particles. The particles were filtered from a depth of 14 m in Esthwaite Water in the English Lake District and handled in anoxic conditions until evacuation in the SPM sample chamber. Two distinct compositions of iron oxide were determined in clusters of about 5 μm diameter. Analysis by PIXE revealed that FeS was uniformly distributed in the particulate material and that it also contained elevated levels of Cu and Zn. This study was the first to demonstrate directly that discrete clusters of iron oxides are present in black particulate material which is commonly considered to comprise iron sulphides.

  18. Overexpression of nuclear AR-V7 protein in primary prostate cancer is an independent negative prognostic marker in men with high-risk disease receiving adjuvant therapy.

    Science.gov (United States)

    Chen, Xin; Bernemann, Christof; Tolkach, Yuri; Heller, Martina; Nientiedt, Cathleen; Falkenstein, Michael; Herpel, Esther; Jenzer, Maximilian; Grüllich, Carsten; Jäger, Dirk; Sültmann, Holger; Duensing, Anette; Perner, Sven; Cronauer, Marcus V; Stephan, Carsten; Debus, Jürgen; Schrader, Andres Jan; Kristiansen, Glen; Hohenfellner, Markus; Duensing, Stefan

    2018-04-01

    Overexpression of the androgen receptor (AR) splice variant 7 (AR-V7) has recently been reported to be associated with resistance to antihormonal therapy. Herein, we address the question whether tumor cells with AR-V7 expression can be detected at the time of radical prostatectomy, that is, before long-term hormonal manipulation and castration resistance, and what the potential prognostic impact on the biochemical recurrence (BCR)-free survival may be. An anti-AR-V7 antibody was first validated in a training set of prostate cancer specimens by a comparison of AR-V7 protein to AR-V7 mRNA expression. We then analyzed nuclear AR-V7 protein expression in the primary tumors and lymph node metastases from 163 predominantly high-risk patients (cohort I) as well as the primary tumors from patients of a second, consecutive patient cohort (n = 238, cohort II) not selected for any clinicopathological features. Staining results were correlated to patient characteristics and BCR-free patient survival. High nuclear AR-V7 protein expression was detected in approximately 30%-40% of patients in cohort I and II at the time of radical prostatectomy. High baseline expression of nuclear AR-V7 protein was associated with an unfavorable BCR-free survival in the high-risk patient cohort I but not in the unselected consecutive cohort II. Remarkably, AR-V7 was an independent negative prognostic factor in high-risk prostate cancer patients of cohort I who were selected to receive adjuvant treatment. Prostate cancer cells with high nuclear AR-V7 protein expression can be detected in a substantial proportion of tumors at the time of radical prostatectomy. The presence of AR-V7-positive tumor cells is associated with an unfavorable prognosis for BCR-free survival in a high-risk patient cohort including a subgroup of patients selected to receive adjuvant therapy, in which AR-V7 was an independent negative prognosticator. Overexpression of nuclear AR-V7 protein hence identifies a subset of tumors

  19. Transfer of suspended particles from liquid effluents of nuclear generating stations through the environment

    International Nuclear Information System (INIS)

    Devereaux, F.J.

    1989-07-01

    Due to the complexity of the environmental transfer of suspended particles in aquatic systems, the available literature usually deals with specific pathways and mechanisms of the transfer process. This paper attempts to give a brief overview of the entire transfer process. Potential routes of transfer in both the marine and freshwater environments are examined, and tentative conclusions presented. This work was performed while the author was employed by Atomic Energy Control Board under the McMaster University cooperative program

  20. Investigation of radiation defects in InSb formed by charged high energy nuclear particles

    International Nuclear Information System (INIS)

    Vikhlij, G.A.; Karpenko, A.Ya.; Litovchenko, P.G.; Tarabrova, L.I.; Groza, A.A.

    1990-01-01

    A possibility of creation of high concentrations of radiation defects in the bulk of InSb samples by 47 MeV protons and 80 MeV alpha particles is considered. Dose dependences of electroconductivity, optical absorption spectra as well as temperature and field relations of galvanomagnetic properties of samples with defects are investigated. Annealing stages and electrical properties of defects annealed at these stages are determined. 17 refs.; 7 figs

  1. Large revealing similarity in multihadron production in nuclear and particle collisions

    International Nuclear Information System (INIS)

    Mishra, Aditya Nath; Sahoo, Raghunath; Sarkisyan, Edward K.G.; Sakharov, Alexander S.; )

    2016-01-01

    The dependencies of charged particle pseudorapidity density and transverse energy pseudorapidity density at midrapidity as well as of charged particle total multiplicity on the collision energy and on the number of nucleon participants, or centrality, measured in nucleus-nucleus collisions are studied in the energy range spanning a few GeV to a few TeV per nucleon. The model in which the multiparticle production is driven by the dissipating effective energy of participants is considered. The model extends the earlier proposed approach, combining the constituent quark picture together with Landau relativistic hydrodynamics shown to interrelate the measurements from different types of collisions. Within this model, the dependence of the charged particle pseudorapidity density and transverse energy pseudorapidity density at midrapidity on the number of participants in heavy-ion collisions are found to be well described in terms of the effective energy defined as a centrality-dependent fraction of the collision energy. For both variables the effective energy approach reveals a similarity in the energy dependence obtained for the most central collisions and centrality data in the entire available energy range

  2. Particle Swarm Optimization to the U-tube steam generator in the nuclear power plant

    International Nuclear Information System (INIS)

    Ibrahim, Wesam Zakaria

    2014-01-01

    Highlights: • We establish stability mathematical model of steam generator and reactor core. • We propose a new Particle Swarm Optimization algorithm. • The algorithm can overcome premature phenomenon and has a high search precision. • Optimal weight of steam generator is 15.1% less than the original. • Sensitivity analysis and optimal design provide reference for steam generator design. - Abstract: This paper, proposed an improved Particle Swarm Optimization approach for optimize a U-tube steam generator mathematical model. The UTSG is one of the most important component related to safety of most of the pressurized water reactor. The purpose of this article is to present an approach to optimization in which every target is considered as a separate objective to be optimized. Multi-objective optimization is a powerful tool for resolving conflicting objectives in engineering design and numerous other fields. One approach to solve multi-objective optimization problems is the non-dominated sorting Particle Swarm Optimization. PSO was applied in regarding the choice of the time intervals for the periodic testing of the model of the steam generator

  3. Particle Swarm Optimization to the U-tube steam generator in the nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, Wesam Zakaria, E-mail: mimi9_m@yahoo.com

    2014-12-15

    Highlights: • We establish stability mathematical model of steam generator and reactor core. • We propose a new Particle Swarm Optimization algorithm. • The algorithm can overcome premature phenomenon and has a high search precision. • Optimal weight of steam generator is 15.1% less than the original. • Sensitivity analysis and optimal design provide reference for steam generator design. - Abstract: This paper, proposed an improved Particle Swarm Optimization approach for optimize a U-tube steam generator mathematical model. The UTSG is one of the most important component related to safety of most of the pressurized water reactor. The purpose of this article is to present an approach to optimization in which every target is considered as a separate objective to be optimized. Multi-objective optimization is a powerful tool for resolving conflicting objectives in engineering design and numerous other fields. One approach to solve multi-objective optimization problems is the non-dominated sorting Particle Swarm Optimization. PSO was applied in regarding the choice of the time intervals for the periodic testing of the model of the steam generator.

  4. Application of optimization numerical methods in calculation of the two-particle nuclear reactions

    International Nuclear Information System (INIS)

    Titarenko, N.N.

    1987-01-01

    An optimization packet of PEAK-OPT applied programs intended for solution of problems of absolute minimization of functions of many variables in calculations of cross sections of binary nuclear reactions is described. The main algorithms of computerized numerical solution of systems of nonlinear equations for the least square method are presented. Principles for plotting and functioning the optimization software as well as results of its practical application are given

  5. Charged particles multiplicity in interactions of 3.7 A GeV 28Si with light and heavy target nuclei in nuclear emulsions

    International Nuclear Information System (INIS)

    Singh, B.K.; Tuli, S.K.

    1998-01-01

    Results from measurement of multiplicity of different charged particles emitted from the interactions of 3.7 A GeV 28 Si with different target groups in nuclear emulsion and correlations among them are presented. The nature of the dependence of multiplicities of charged particles on the impact parameter is examined. Analysis of data in terms of specific multiplicity for different target groups is performed and the results are discussed in the light of superposition model. (author)

  6. Fluorescent nuclear track images of Ag-activated phosphate glass irradiated with photons and heavy charged particles

    Energy Technology Data Exchange (ETDEWEB)

    Kurobori, Toshio, E-mail: kurobori@staff.kanazawa-u.ac.jp [Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192 (Japan); Yanagida, Yuka [Oarai Research Center, Chiyoda Technol Corporation, Oarai-machi, Ibaraki 311-1313 (Japan); Kodaira, Satoshi [National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Shirao, Taichi [Nikon Instech Co., Ltd., Tanakanishi, Sakyo-ku, Kyoto 606-8221 (Japan)

    2017-05-21

    In this paper we report about the demonstration of the nuclear track imaging capabilities of Ag-activated phosphate glass. A 375 nm laser and confocal laser scanning microscopy (CLSM) were respectively used for track excitation and detection. Specifically, the blue and orange radiophotoluminescent (RPL) tracks and dose distributions observed after irradiation with soft X-rays, gamma rays and heavy charged particles (HCPs) are examined. In addition, the origins of the reductions in RPL efficiency for high-dose X-ray irradiation and for irradiation with HCPs with high linear energy transfer (LET) values are investigated via a CLSM and a conventional fluorescent reader and discussed. - Highlights: • 3D track images are demonstrated using a confocal laser microscopy. • Fluorescent track detectors are based on RPL Ag-doped phosphate glass. • The dose distributions are examined for X-ray, gamma ray and HCP irradiations. • The origins of the reduction in RPL efficiency are investigated and discussed.

  7. Investigation of rare particle production in high energy nuclear collisions. Progress report, December 15, 1997--December 14, 1998

    International Nuclear Information System (INIS)

    Crawford, H.J.; Engelage, J.

    1998-01-01

    The program is an investigation of the hadronization process through experimental measurement of rare particle production in high energy nuclear interactions. These interactions provide an environment similar in energy density to the conditions in the Big Bang. The authors are currently involved in two major experiments to study this environment, E896 at the AGS and STAR at RHIC. They have completed the first physics running of E896, a search for the H dibaryon and measurement of hyperon production in AuAu collisions, and are in the process of analyzing the data. They have prototyped the STAR trigger and are in the process of fabricating its components and installing them in the STAR detector

  8. Fluorescent nuclear track images of Ag-activated phosphate glass irradiated with photons and heavy charged particles

    International Nuclear Information System (INIS)

    Kurobori, Toshio; Yanagida, Yuka; Kodaira, Satoshi; Shirao, Taichi

    2017-01-01

    In this paper we report about the demonstration of the nuclear track imaging capabilities of Ag-activated phosphate glass. A 375 nm laser and confocal laser scanning microscopy (CLSM) were respectively used for track excitation and detection. Specifically, the blue and orange radiophotoluminescent (RPL) tracks and dose distributions observed after irradiation with soft X-rays, gamma rays and heavy charged particles (HCPs) are examined. In addition, the origins of the reductions in RPL efficiency for high-dose X-ray irradiation and for irradiation with HCPs with high linear energy transfer (LET) values are investigated via a CLSM and a conventional fluorescent reader and discussed. - Highlights: • 3D track images are demonstrated using a confocal laser microscopy. • Fluorescent track detectors are based on RPL Ag-doped phosphate glass. • The dose distributions are examined for X-ray, gamma ray and HCP irradiations. • The origins of the reduction in RPL efficiency are investigated and discussed.

  9. Order, chaos and nuclear dynamics: An introduction

    International Nuclear Information System (INIS)

    Swiatecki, W.J.

    1990-08-01

    This is an introductory lecture illustrating by simple examples the anticipated effect on collective nuclear dynamics of a transition from order to chaos in the motions of nucleons inside an idealized nucleus. The destruction of order is paralleled by a transition from a rubber-like to a honey-like behaviour of the independent-particle nuclear model. 10 refs., 6 figs

  10. Competition between collective and single particle excitations in nuclear structure description

    International Nuclear Information System (INIS)

    Petrovici, A.N.

    1983-01-01

    The microscopic description of the quadrupole collective dynamics in even krypton isotopes is presented. A microscopic calculation of Bohr's collective Hamiltonian is used to describe the collective motion in 76 Kr. A single-particle basis calculated in a deformed Woods-Saxon potential leads to the potential energy surface obtained by the Strutinsky renormalization procedure, and to the inertial functions determined in the cranking model approximation. The collective Schroedinger equation is solved numerically to analyse the low-energy, even parity states in 76 Kr. A good agreement between experiment and theory is obtained without specifically adjusting any parameter in the model for this nucleus. Some results regarding statical and dynamical characteristics of sup(74,78,80)Kr isotopes are also presented. The asymmetric rotor model with admixture of two quasiparticles is used to describe the sup(66,68,70)Ge and the sup(64,66)Zn isotopes. The interplay of collective and single particle motions is further investigated by magnetic moment measurements using the method of integral angular correlations perturbed by recoil into gas. The results involve g-factor measurements for 166 Ho, 68 Ge, 64 Zn, 66 Zn and 68 Ga nuclei. Finally, a discussion of further possible improvements and more general developments of the problems under investigation is given. (author)

  11. Hydrogen peroxide-induced DNA damage is independent of nuclear calcium but dependent on redox-active ions.

    Science.gov (United States)

    Jornot, L; Petersen, H; Junod, A F

    1998-01-01

    In cells undergoing oxidative stress, DNA damage may result from attack by .OH radicals produced by the Fenton reaction, and/or by nucleases activated by nuclear calcium. In the present study, the participation of these two mechanisms was investigated in HeLa cells. Nuclear-targeted aequorin was used for selectively monitoring Ca2+ concentrations within the nuclei ([Ca2+]n), in conjunction with the cell-permeant calcium chelator bis-(o-aminophenoxy)ethane-N,N,N', N'-tetraacetic acid acetoxymethyl ester (BAPTA/AM), the lipid-soluble broad-spectrum metal chelator with low affinity for Ca2+ and Mg2+ N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN), and the high-affinity iron/copper chelator 1, 10-phenanthroline (PHE). In Ca2+-containing medium, H2O2 induced extensive DNA strand breaks and an increase in [Ca2+]n that was almost identical to that observed in the cytosol ([Ca2+]c). In cells bathed in Ca2+-free/EGTA medium, in which the increases in [Ca2+]n and [Ca2+]c due to H2O2 were significantly reduced, similar levels of DNA fragmentation also occurred. In cells preloaded with BAPTA/AM or TPEN, the small increase of [Ca2+]n normally elicited by H2O2 in Ca2+-free medium was completely buffered, and DNA damage was largely prevented. On the other hand, pretreatment with PHE did not affect the calcium response in the nuclei, but completely prevented DNA strand breakage induced by H2O2. Re-addition of 100 microM CuSO4 and 100 microM FeSO4 to TPEN- and PHE-treated cells prior to H2O2 challenge reversed the effect of TPEN and PHE, whereas 1 mM was necessary to negate the effect of BAPTA/AM. The levels of DNA strand breakage observed, however, did not correlate with the amounts of 8-hydroxy 2'-deoxyguanosine (8-OHdG): H2O2 did not produce 8-OHdG, whereas PHE alone slightly increased 8-OHdG levels. CuSO4 and FeSO4 enhanced the effects of PHE, particularly in the presence of H2O2. Exposure of cells to a mixture of CuSO4/FeSO4 also resulted in a significant increase in

  12. In-situ removal and characterisation of uranium-containing particles from sediments surrounding the Fukushima Daiichi Nuclear Power Plant

    Science.gov (United States)

    Martin, P. G.; Griffiths, I.; Jones, C. P.; Stitt, C. A.; Davies-Milner, M.; Mosselmans, J. F. W.; Yamashiki, Y.; Richards, D. A.; Scott, T. B.

    2016-03-01

    Traditional methods to locate and subsequently study radioactive fallout particles have focused heavily on autoradiography coupled with in-situ analytical techniques. Presented here is the application of a Variable Pressure Scanning Electron Microscope with both backscattered electron and energy dispersive spectroscopy detectors, along with a micromanipulator setup and electron-hardening adhesive to isolate and remove individual particles before synchrotron radiation analysis. This system allows for a greater range of new and existing analytical techniques, at increased detail and speed, to be applied to the material. Using this method, it was possible to erform detailed energy dispersive spectroscopy and synchrotron radiation characterisation of material likely ejected from the Fukushima Daiichi Nuclear Power Plant found within a sediment sample collected from the edge of the 30 km exclusion zone. Particulate material sub-micron in maximum dimension examined during this work via energy dispersive spectroscopy was observed to contain uranium at levels between 19.68 and 28.35 weight percent, with the application of synchrotron radiation spectroscopy confirming its presence as a major constituent. With great effort and cost being devoted to the remediation of significant areas of eastern Japan affected by the incident, it is crucial to gain the greatest possible understanding of the nature of this contamination in order to inform the most appropriate clean-up response.

  13. Some characteristics of the CR-39 solid state nuclear - Track Detector for register of protons and low energy alpha particles

    International Nuclear Information System (INIS)

    Fonseca, E.S. da.

    1983-01-01

    Experimental results related to registration properties of the CR-39 Solid State Nuclear Track Detector for charged particles are presented and discussed. The existence of an inverse proportion between the induction time and the temperature as well as normal concentration of solutions, is showed by the study of CR-39 chemical etching characteristics in NaOH and KOH solutions, comprising varied concentration and temperature. The bulk-etch rate and activation energy of the process were obtained. The critical energy and critical energy-loss rate of CR-39 track-detectors for registration of protons were experimentally determined. Samples were exposed to 24 Mev proton beams in the IEN/CNEN Cyclotron (CV-28), using scattering chamber with a tantalum thin target and aluminium absorbers in contact with the samples, in order to provide the required fluctuation in the scattered beam energy. From the mean track-diameter plotted against incident proton energy the critical energy was obtained. From the calculated energy-loss rate vs. energy curve, the critical energy loss rate were evaluated. The CR-39 response for low energy alpha particles (E = 7h) under the conditions of 6.25 N NaOH at 70 0 C. It is shown that successive chemical etchings do not produce the same track geometry as obtained by means of a continous revelation with the same total etching time. (Author) [pt

  14. Nuclear chemical method for preparation of free carbenium ions and radiochemical investigation of reactions of these particles

    International Nuclear Information System (INIS)

    Nefedov, V.D.; Sinotova, E.N.; Toropova, M.A.

    1980-01-01

    Tritium nuclear transformation (β-decay) in the composition of the molecules of hydrocarbons, appearance of primary molecular ions and formation of free carbenium ion are the main items of nuclear-chemical method of preparation of free carbenium ions. The method permits to prepare carbenium ions present in free state, i.e. without counterion and without solvate sheath of variou nitial localization of the charge. The rate of carbenium ion generation is strictly definite and does not depend upon outer conditions. The method suggested permits to prepare carbenium ions in all phases, study their reactions with individual substances in gaseous, liquid and solid states. The study of ion-molecular reactions is carried out using radiochemical method. The analysis of the products is made using the method of gaseous radiochromatography. Development of preparation techniques of carbenium ions and their analogues, study of the reactions of these particles with different classes of compounds, investigation of the effect of different factors upon procedure of ion-molecular reactions are the main directions of the investigations

  15. Study of the prompt gamma ray signal from fissions in special nuclear materials induced using an associated particle neutron generator

    International Nuclear Information System (INIS)

    Koltick, D. S.; Kane, S. Z.

    2009-01-01

    More than 42 million cargo containers entered the United States in 2005. To search for a few kilograms of special nuclear material (SNM) within this vast stream of cargo, an inspection system based on neutron-induced fission followed by the coincident detection of multiple prompt fission gamma rays is investigated using MCNP-Polimi code. The system utilizes two deuterium-tritium (DT) associated particle neutron generators, each capable of 10 9 neutrons/s at 14.1 MeV, with sub-nanosecond timing resolution ZnO:Ga alpha detectors internal to the generator. Because prompt fission signals are approximately 100 times stronger than the delayed signals, the neutron flux is greatly reduced compared to 10 11-12 neutrons/s required for systems based on delayed signals such as the 'nuclear car wash' [4]. In addition the system utilizes 30 cm deep liquid krypton (LKr) noble gas detectors having 94% detection efficiency for 1 MeV gamma rays, high solid angle coverage (∼ 50% of the total solid angle), and sub-nanosecond timing resolution (∼ 600 ps). An algorithm for distinguishing U-235 from U-238 is presented. (authors)

  16. Cross section measurement of alpha particle induced nuclear reactions on natural cadmium up to 52MeV.

    Science.gov (United States)

    Ditrói, F; Takács, S; Haba, H; Komori, Y; Aikawa, M

    2016-12-01

    Cross sections of alpha particle induced nuclear reactions have been measured on thin natural cadmium targets foils in the energy range from 11 to 51.2MeV. This work was a part of our systematic study on excitation functions of light ion induced nuclear reactions on different target materials. Regarding the cross sections, the alpha induced reactions are not deeply enough investigated. Some of the produced isotopes are of medical interest, others have application in research and industry. The radioisotope 117m Sn is a very important theranostic (therapeutic + diagnostic) radioisotope, so special care was taken to the results for that isotope. The well-established stacked foil technique followed by gamma-spectrometry with HPGe gamma spectrometers were used. The target and monitor foils in the stack were commercial high purity metal foils. From the irradiated targets 117m Sn, 113 Sn, 110 Sn, 117m,g In, 116m In, 115m In, 114m In, 113m In, 111 In, 110m,g In, 109m In, 108m,g In, 115g Cd and 111m Cd were identified and their excitation functions were derived. The results were compared with the data of the previous measurements from the literature and with the results of the theoretical nuclear reaction model code calculations TALYS 1.8 (TENDL-2015) and EMPIRE 3.2 (Malta). From the cross section curves thick target yields were calculated and compared with the available literature data. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Analysis of C. elegans NR2E nuclear receptors defines three conserved clades and ligand-independent functions

    Directory of Open Access Journals (Sweden)

    Weber Katherine P

    2012-06-01

    Full Text Available Abstract Background The nuclear receptors (NRs are an important class of transcription factors that are conserved across animal phyla. Canonical NRs consist of a DNA-binding domain (DBD and ligand-binding domain (LBD. While most animals have 20–40 NRs, nematodes of the genus Caenorhabditis have experienced a spectacular proliferation and divergence of NR genes. The LBDs of evolutionarily-conserved Caenorhabditis NRs have diverged sharply from their Drosophila and vertebrate orthologs, while the DBDs have been strongly conserved. The NR2E family of NRs play critical roles in development, especially in the nervous system. In this study, we explore the phylogenetics and function of the NR2E family of Caenorhabditis elegans, using an in vivo assay to test LBD function. Results Phylogenetic analysis reveals that the NR2E family of NRs consists of three broadly-conserved clades of orthologous NRs. In C. elegans, these clades are defined by nhr-67, fax-1 and nhr-239. The vertebrate orthologs of nhr-67 and fax-1 are Tlx and PNR, respectively. While the nhr-239 clade includes orthologs in insects (Hr83, an echinoderm, and a hemichordate, the gene appears to have been lost from vertebrate lineages. The C. elegans and C. briggsae nhr-239 genes have an apparently-truncated and highly-diverged LBD region. An additional C. elegans NR2E gene, nhr-111, appears to be a recently-evolved paralog of fax-1; it is present in C. elegans, but not C. briggsae or other animals with completely-sequenced genomes. Analysis of the relatively unstudied nhr-111 and nhr-239 genes demonstrates that they are both expressed—nhr-111 very broadly and nhr-239 in a small subset of neurons. Analysis of the FAX-1 LBD in an in vivo assay revealed that it is not required for at least some developmental functions. Conclusions Our analysis supports three conserved clades of NR2E receptors, only two of which are represented in vertebrates, indicating three ancestral NR2E genes in the

  18. The induction of rho'- mutants by UV or γ-rays is independent of the nuclear recombinational repair pethway in Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Heude, M

    1988-01-01

    In order to discover whether the nuclear recombinational repair pathway also acts on lesions induced in mitochondrial DNA (mtDNA), the possible role of the RAD50, -51, -55 and -56 genes on the induction of rho - mutants by radiations was studied. Such induction appeared to be independent of this pathway. Nevertheless, an efficient induction of respiration-deficient mutants was observed in γ-irradiated rad52 diploids. We demonstrate that these mutants do not result from a lack of mtDNA repair, but from chromosome losses induced by γ-rays. Such an impairment of the respiratory ability of diploids by chromosome lossed was effectively observed in the aneuploid progeny of unirradiated RAD + cdc6 diploids incubated at the restrictive temperature. (author). 60 refs.; 3 figs.; 6 tabs

  19. Nuclear polarization potential due to particle transfer in heavy-ion collisions

    International Nuclear Information System (INIS)

    Landowne, S.; Dasso, C.H.; Winther, A.; Pollarolo, G.

    1986-01-01

    The effective interaction which determines the elastic scattering of heavy composite systems consists of a ''bare'' real potential V, noramally identified with the folding model, a renormalization term or ''polarization potential'' ΔV and an imaginary ''absorptive potential'' iW. The latter contributions originate from the couplings to intrinsic degrees of freedom. While iW is a conspicuous feature of all optical model analyses, the related term ΔV has received relatively little attention until recently. The microscopic structure of ΔV + iW is examined using second-order semi-classical perturbation theory. Focus is on the long-range part of ΔV which is governed by single-particle transfer reactions between the colliding systems

  20. Nuclear polarization potential due to particle transfer in heavy-ion collisions

    International Nuclear Information System (INIS)

    Landowne, S.; Dasso, C.H.; Winther, A.; Pollarolo, G.

    1986-01-01

    The effective interaction which determines the elastic scattering of heavy composite systems consists of a bare real potential V, normally identified with the folding model, a renormalization term or polarization potential ΔV and an imaginary absorptive potential iW. The latter contributions originate from the couplings to intrinsic degrees of freedom. While iW is a conspicuous feature of all optical model analyses, the related term ΔV has received relatively little attention until recently. Here the authors examine the microscopic structure of ΔV + IW using second-order semi-classical perturbation theory. In particular, they focus on the long-range part of ΔV which is governed by single-particle transfer reactions between the colliding systems