WorldWideScience

Sample records for nuclear field effect

  1. Effective masses and the nuclear mean field

    International Nuclear Information System (INIS)

    Mahaux, C.; Sartor, R.

    1985-01-01

    The effective mass characterizes the energy dependence of the empirical average nuclear potential. This energy dependence has two different sources, namely the nonlocality in space of the microscopic mean field on the one hand, and its true energy dependence on the other hand. Correspondingly it is convenient to divide the effective mass into two components, the k-mass and the ω-mass. The latter is responsible for the existence of a peak in the energy dependence of the effective mass. This peak is located near the Fermi energy in nuclear matter and in nuclei, as well as in the electron gas, the hard sphere Fermi gas and liquid helium 3. A related phenomenon is the existence of a low energy anomaly in the energy dependence of the optical model potential between two heavy ions. (orig.)

  2. Nuclear parity violation in effective field theory

    International Nuclear Information System (INIS)

    Zhu Shilin; Maekawa, C.M.; Holstein, B.R.; Ramsey-Musolf, M.J.; Kolck, U. van

    2005-01-01

    We reformulate the analysis of nuclear parity violation (PV) within the framework of effective field theory (EFT). To O(Q), the PV nucleon-nucleon (NN) interaction depends on five a priori unknown constants that parameterize the leading-order, short-range four-nucleon operators. When pions are included as explicit degrees of freedom, the potential contains additional medium- and long-range components parameterized by PV πNN coupling. We derive the form of the corresponding one- and two-pion-exchange potentials. We apply these considerations to a set of existing and prospective PV few-body measurements that may be used to determine the five independent low-energy constants relevant to the pionless EFT and the additional constants associated with dynamical pions. We also discuss the relationship between the conventional meson-exchange framework and the EFT formulation, and argue that the latter provides a more general and systematic basis for analyzing nuclear PV

  3. Nuclear Forces from Effective Field Theory

    International Nuclear Information System (INIS)

    Krebs, H.

    2011-01-01

    Chiral effective field theory allows for a systematic and model-independent derivation of the forces between nucleons in harmony with the symmetries of the quantum chromodynamics. After a brief review on the current status in the development of the chiral nuclear forces I will focus on the role of the Δ-resonance contributions in the nuclear dynamics.We find improvement in the convergence of the chiral expansion of the nuclear forces if we explicitly take into account the Δ-resonance degrees of freedom. The overall results for two-nucleon forces with and without explicit Δ-resonance degrees of freedom are remarkably similar. We discussed the long- and shorter-range N 3 LO contributions to chiral three-nucleon forces. No additional free parameters appear at this order. There are five different topology classes which contribute to the forces. Three of them describe long-range contributions which constitute the first systematic corrections to the leading 2π exchange that appear at N 2 LO. Another two contributions are of a shorter range and include, additionally to an exchange of pions, also one short-range contact interaction and all corresponding 1/m corrections. The requirement of renormalizability leads to unique expressions for N 3 LO contributions to the three-nucleon force (except for 1/m-corrections). We presented the complete N 2 LO analysis of the nuclear forces with explicit Δ-isobar degrees of freedom. Although the overall results in the isospin-conserving case are very similar in the Δ-less and Δ-full theories, we found a much better convergence in all peripheral partial waves once Δ-resonance is explicitly taken into account. The leading CSB contributions to nuclear forces are proportional to nucleon- and Δ-mass splittings. There appear strong cancellations between the two contributions which at leading order yield weaker V III potentials. This effect is, however, entirely compensated at subleading order such that the results in the theories

  4. Nuclear matter from chiral effective field theory

    International Nuclear Information System (INIS)

    Drischler, Christian

    2017-01-01

    Nuclear matter is an ideal theoretical system that provides key insights into the physics of different length scales. While recent ab initio calculations of medium-mass to heavy nuclei have demonstrated that realistic saturation properties in infinite matter are crucial for reproducing experimental binding energies and charge radii, the nuclear-matter equation of state allows tight constraints on key quantities of neutron stars. In the present thesis we take advantage of both aspects. Chiral effective field theory (EFT) with pion and nucleon degrees of freedom has become the modern low-energy approach to nuclear forces based on the symmetries of quantum chromodynamics, the fundamental theory of strong interactions. The systematic chiral expansion enables improvable calculations associated with theoretical uncertainty estimates. In recent years, chiral many-body forces were derived up to high orders, allowing consistent calculations including all many-body contributions at next-to-next-to-next-to-leading order (N 3 LO). Many further advances have driven the construction of novel chiral potentials with different regularization schemes. Here, we develop advanced methods for microscopic calculations of the equation of state of homogeneous nuclear matter with arbitrary proton-to-neutron ratio at zero temperature. Specifically, we push the limits of many-body perturbation theory (MBPT) considerations to high orders in the chiral and in the many-body expansion. To address the challenging inclusion of three-body forces, we introduce a new partial-wave method for normal ordering that generalizes the treatment of these contributions. We show improved predictions for the neutron-matter equation of state with consistent N 3 LO nucleon-nucleon (NN) plus three-nucleon (3N) potentials using MBPT up to third order and self-consistent Green's function theory. The latter also provides nonperturbative benchmarks for the many-body convergence. In addition, we extend the normal

  5. Nuclear matter from chiral effective field theory

    Energy Technology Data Exchange (ETDEWEB)

    Drischler, Christian

    2017-11-15

    Nuclear matter is an ideal theoretical system that provides key insights into the physics of different length scales. While recent ab initio calculations of medium-mass to heavy nuclei have demonstrated that realistic saturation properties in infinite matter are crucial for reproducing experimental binding energies and charge radii, the nuclear-matter equation of state allows tight constraints on key quantities of neutron stars. In the present thesis we take advantage of both aspects. Chiral effective field theory (EFT) with pion and nucleon degrees of freedom has become the modern low-energy approach to nuclear forces based on the symmetries of quantum chromodynamics, the fundamental theory of strong interactions. The systematic chiral expansion enables improvable calculations associated with theoretical uncertainty estimates. In recent years, chiral many-body forces were derived up to high orders, allowing consistent calculations including all many-body contributions at next-to-next-to-next-to-leading order (N{sup 3}LO). Many further advances have driven the construction of novel chiral potentials with different regularization schemes. Here, we develop advanced methods for microscopic calculations of the equation of state of homogeneous nuclear matter with arbitrary proton-to-neutron ratio at zero temperature. Specifically, we push the limits of many-body perturbation theory (MBPT) considerations to high orders in the chiral and in the many-body expansion. To address the challenging inclusion of three-body forces, we introduce a new partial-wave method for normal ordering that generalizes the treatment of these contributions. We show improved predictions for the neutron-matter equation of state with consistent N{sup 3}LO nucleon-nucleon (NN) plus three-nucleon (3N) potentials using MBPT up to third order and self-consistent Green's function theory. The latter also provides nonperturbative benchmarks for the many-body convergence. In addition, we extend the

  6. Effective field theory approach to nuclear matter

    International Nuclear Information System (INIS)

    Saviankou, P.; Gruemmer, F.; Epelbaum, E.; Krewald, S.; Meissner, Ulf-G.

    2006-01-01

    Effective field theory provides a systematic approach to hardon physics and few-nucleon systems. It allows one to determine the effective two-, three-, and more-nucleon interactions which are consistent with each other. We present a project to derive bulk properties of nuclei from the effective nucleonic interactions

  7. Versatility of field theory motivated nuclear effective Lagrangian approach

    International Nuclear Information System (INIS)

    Arumugam, P.; Sharma, B.K.; Sahu, P.K.; Patra, S.K.; Sil, Tapas; Centelles, M.; Vinas, X.

    2004-01-01

    We analyze the results for infinite nuclear and neutron matter using the standard relativistic mean field model and its recent effective field theory motivated generalization. For the first time, we show quantitatively that the inclusion in the effective theory of vector meson self-interactions and scalar-vector cross-interactions explains naturally the recent experimental observations of the softness of the nuclear equation of state, without losing the advantages of the standard relativistic model for finite nuclei

  8. Towards a chiral effective field theory of nuclear matter

    International Nuclear Information System (INIS)

    Mallik, S.

    2008-01-01

    As a preliminary attempt to formulate an effective theory of nuclear matter, we undertake to calculate the effective pole parameters of nucleon in such a medium. We begin with the virial expansion of these parameters to leading order in nucleon number density in terms of the on-shell NN scattering amplitude. We then proceed to calculate the same parameters in the effective theory, getting a formula for the nucleon mass-shift to leading order, that was known already to give too large a value to be acceptable at normal nuclear density. At this point the virial expansion suggests a modification of this formula, which we carry out following Weinberg's method for the two-nucleon system in the effective theory. The results are encouraging enough to attempt a complete, next-to-leading order calculation of the off-shell nucleon spectral function in nuclear medium. (author)

  9. Nuclear Lattice Simulations with Chiral Effective Field Theory

    OpenAIRE

    Lee, Dean

    2008-01-01

    We present recent results on lattice simulations using chiral effective field theory. In particular we discuss lattice simulations for dilute neutron matter at next-to-leading order and three-body forces in light nuclei at next-to-next-to-leading order.

  10. Hyperons in nuclear matter from SU(3) chiral effective field theory

    Energy Technology Data Exchange (ETDEWEB)

    Petschauer, S.; Kaiser, N. [Technische Universitaet Muenchen, Physik Department, Garching (Germany); Haidenbauer, J. [Institut fuer Kernphysik, Forschungszentrum Juelich, Institute for Advanced Simulation, Juelich Center for Hadron Physics, Juelich (Germany); Meissner, Ulf G. [Institut fuer Kernphysik, Forschungszentrum Juelich, Institute for Advanced Simulation, Juelich Center for Hadron Physics, Juelich (Germany); Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Bonn (Germany); Weise, W. [Technische Universitaet Muenchen, Physik Department, Garching (Germany); Villa Tambosi, ECT, Villazzano (Trento) (Italy)

    2016-01-15

    Brueckner theory is used to investigate the properties of hyperons in nuclear matter. The hyperon-nucleon interaction is taken from chiral effective field theory at next-to-leading order with SU(3) symmetric low-energy constants. Furthermore, the underlying nucleon-nucleon interaction is also derived within chiral effective field theory. We present the single-particle potentials of Λ and Σ hyperons in symmetric and asymmetric nuclear matter computed with the continuous choice for intermediate spectra. The results are in good agreement with the empirical information. In particular, our calculation gives a repulsive Σ-nuclear potential and a weak Λ-nuclear spin-orbit force. (orig.)

  11. Nuclear electric dipole moments in chiral effective field theory

    Energy Technology Data Exchange (ETDEWEB)

    Bsaisou, J.; Vries, J. de [Institute for Advanced Simulation, Institut für Kernphysik, and Jülich Center for Hadron Physics,Forschungszentrum Jülich, D-52425 Jülich (Germany); Hanhart, C. [Institute for Advanced Simulation, Institut für Kernphysik, and Jülich Center for Hadron Physics,Forschungszentrum Jülich, D-52425 Jülich (Germany); JARA - Forces and Matter Experiments,Forschungszentrum Jülich, D-52425 Jülich (Germany); Liebig, S. [Institute for Advanced Simulation, Institut für Kernphysik, and Jülich Center for Hadron Physics,Forschungszentrum Jülich, D-52425 Jülich (Germany); Meißner, Ulf-G. [Institute for Advanced Simulation, Institut für Kernphysik, and Jülich Center for Hadron Physics,Forschungszentrum Jülich, D-52425 Jülich (Germany); JARA - Forces and Matter Experiments,Forschungszentrum Jülich, D-52425 Jülich (Germany); JARA - High Performance Computing,Forschungszentrum Jülich, D-52425 Jülich (Germany); Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics,Universität Bonn,D-53115 Bonn (Germany); Minossi, D. [Institute for Advanced Simulation, Institut für Kernphysik, and Jülich Center for Hadron Physics,Forschungszentrum Jülich, D-52425 Jülich (Germany); Nogga, A.; Wirzba, A. [Institute for Advanced Simulation, Institut für Kernphysik, and Jülich Center for Hadron Physics,Forschungszentrum Jülich, D-52425 Jülich (Germany); JARA - Forces and Matter Experiments,Forschungszentrum Jülich, D-52425 Jülich (Germany)

    2015-03-19

    We provide a consistent and complete calculation of the electric dipole moments of the deuteron, helion, and triton in the framework of chiral effective field theory. The CP-conserving and CP-violating interactions are treated on equal footing and we consider CP-violating one-, two-, and three-nucleon operators up to next-to-leading-order in the chiral power counting. In particular, we calculate for the first time EDM contributions induced by the CP-violating three-pion operator. We find that effects of CP-violating nucleon-nucleon contact interactions are larger than those found in previous studies based on phenomenological models for the CP-conserving nucleon-nucleon interactions. Our results which apply to any model of CP violation in the hadronic sector can be used to test various scenarios of CP violation. As examples, we study the implications of our results on the QCD θ-term and the minimal left-right symmetric model.

  12. Sigma exchange in the nuclear force and effective field theory

    International Nuclear Information System (INIS)

    Donoghue, John F.

    2006-01-01

    In the phenomenological description of the nuclear interaction an important role is traditionally played by the exchange of a scalar I=0 meson, the sigma, of mass 500-600 MeV, which however is not seen clearly in the particle spectrum and which has a very ambiguous status in QCD. I show that a remarkably simple and reasonably controlled combination of ingredients can reproduce the features of this part of the nuclear force. The use of chiral perturbation theory calculations for two pion exchange supplemented by the Omnes function for pion rescattering suffices to reproduce the magnitude and shape of the exchange of a supposed σ particle. I also attempt to relate this description to the contact interaction that enters more modern descriptions of the internucleon interaction

  13. Retardation and dispersive effects in the nuclear mean field

    International Nuclear Information System (INIS)

    Mahaux, C.; Davies, K.T.R.; Satchler, G.R.

    1993-01-01

    We consider several parametrizations of the energy dependence of the imaginary part of the mean field, for nucleons as well as heavy ions. These parametrizations specify the energy dependence of the corresponding real part, because the real and imaginary parts are connected by a dispersion relation. The latter can be viewed as equivalent to the causality property. Since Hilbert transforms appear in the dispersion relation and since Fourier transforms give the correspondence between energy dependence and temporal nonlocality, we derive several properties of these transforms which are of particular interest in the present context. The most useful one is that the Fourier transform of a function F(E) which is analytic in the upper half of the complex E-plane can be expressed in terms of the Fourier transform of the imaginary part of F(E) alone. We investigate several schematic models for the mean field. They fall into two main categories. These correspond to the two main definitions which have been proposed for the mean field, namely the self-energy and Feshbach's potential. Both of these definitions can be used for the nucleon-nucleus system, in which case they correspond to two different ways of handling the combined influence of ground state correlations and antisymmetrization. The resulting two mean fields have different energy dependences and, correspondingly, temporal nonlocalities. Feshbach's approach can also be applied to the nucleus-nucleus system. Our schematic models are semi-realistic, in the sense that they all take account of the 'Fermi surface anomaly' for the nucleon-nucleus system or of the 'threshold anomaly' for the nucleus-nucleus case. The temporal nonlocality is investigated for each model. A physical interpretation of this nonlocality is given in terms delay of the response of the medium, in which an incident wave is partially trapped in nonelastic channels and subsequently reemitted. (orig./HSI)

  14. Hyperons in nuclear matter from SU(3) chiral effective field theory

    Energy Technology Data Exchange (ETDEWEB)

    Petschauer, Stefan; Kaiser, Norbert [Technische Universitaet Muenchen (Germany); Haidenbauer, Johann [Forschungszentrum Juelich (Germany); Meissner, Ulf G. [Forschungszentrum Juelich (Germany); Universitaet Bonn (Germany); Weise, Wolfram [Technische Universitaet Muenchen (Germany); ECT, Trento (Italy)

    2016-07-01

    Brueckner theory is used to investigate the properties of hyperons in nuclear matter. The hyperon-nucleon interaction is taken from chiral effective field theory at next-to-leading order with SU(3) symmetric low-energy constants. Furthermore, the underlying nucleon-nucleon interaction is also derived within chiral effective field theory. We present the single-particle potentials of Λ and Σ hyperons in symmetric and asymmetric nuclear matter computed with the continuous choice for intermediate spectra. The results are in good agreement with the empirical information. In particular, our calculation gives a repulsive Σ-nuclear potential and a weak Λ-nuclear spin-orbit force. The splittings among the Σ{sup +}, Σ{sup 0} and Σ{sup -} potentials have a non-linear dependence on the isospin asymmetry which goes beyond the usual parametrization in terms of an isovector Lane potential.

  15. The ``Folk Theorem'' on effective field theory: How does it fare in nuclear physics?

    Science.gov (United States)

    Rho, Mannque

    2017-10-01

    This is a brief history of what I consider as very important, some of which truly seminal, contributions made by young Korean nuclear theorists, mostly graduate students working on PhD thesis in 1990s and early 2000s, to nuclear effective field theory, nowadays heralded as the first-principle approach to nuclear physics. The theoretical framework employed is an effective field theory anchored on a single scale-invariant hidden local symmetric Lagrangian constructed in the spirit of Weinberg's "Folk Theorem" on effective field theory. The problems addressed are the high-precision calculations on the thermal np capture, the solar pp fusion process, the solar hep process — John Bahcall's challenge to nuclear theorists — and the quenching of g A in giant Gamow-Teller resonances and the whopping enhancement of first-forbidden beta transitions relevant in astrophysical processes. Extending adventurously the strategy to a wild uncharted domain in which a systematic implementation of the "theorem" is far from obvious, the same effective Lagrangian is applied to the structure of compact stars. A surprising, unexpected, result on the properties of massive stars, totally different from what has been obtained up to day in the literature, is predicted, such as the precocious onset of conformal sound velocity together with a hint for the possible emergence in dense matter of hidden symmetries such as scale symmetry and hidden local symmetry.

  16. Baryonic forces and hyperons in nuclear matter from SU(3) chiral effective field theory

    Energy Technology Data Exchange (ETDEWEB)

    Petschauer, Stefan Karl

    2016-02-12

    In this work the baryon-baryon interaction is studied at next-to-leading order in SU(3) chiral effective field theory and applied to hyperon-nucleon scattering. The properties of hyperons in isospin-symmetric as well as asymmetric nuclear matter are calculated within the Bruecker-Hartree-Fock formalism. Moreover, the leading three-baryon interaction is derived and its low-energy constants are estimated from decuplet intermediate states. We conclude, that chiral effective field theory is a well-suited tool to describe the baryonic forces.

  17. Views of a devil's advocate -- Fundamental challenges to effective field theory treatments of nuclear physics

    International Nuclear Information System (INIS)

    Cohen, T.D.

    1998-04-01

    The physics goals of the effective field theory program for nuclear phenomena are outlined. It is pointed out that there are multiple schemes for implementing EFT and it is presently not clear if any of these schemes is viable. Most of the applications of effective field theory ideas have been on nucleon-nucleon scattering. It is argued that this is little more than curve fitting and that other quantities need to be calculated to test the ideas. It is shown that EFT methods work well for certain bound state properties of the deuteron electric form factor. However, it is also shown that this success depends sensitively on the fact that the majority of the probability of the deuteron's wave function is beyond the range of the potential. This circumstance is special to the deuteron suggesting that it will be very difficult to achieve the same kinds of success for tightly bound nuclei

  18. Nuclear magnetic resonance studies of quadrupolar nuclei and dipolar field effects

    International Nuclear Information System (INIS)

    Urban, Jeffry Todd

    2004-01-01

    Experimental and theoretical research conducted in two areas in the field of nuclear magnetic resonance (NMR) spectroscopy is presented: (1) studies of the coherent quantum-mechanical control of the angular momentum dynamics of quadrupolar (spin I > 1/2) nuclei and its application to the determination of molecular structure; and (2) applications of the long-range nuclear dipolar field to novel NMR detection methodologies.The dissertation is organized into six chapters. The first two chapters and associated appendices are intended to be pedagogical and include an introduction to the quantum mechanical theory of pulsed NMR spectroscopy and the time dependent theory of quantum mechanics. The third chapter describes investigations of the solid-state multiple-quantum magic angle spinning (MQMAS) NMR experiment applied to I 5/2 quadrupolar nuclei. This work reports the use of rotary resonance-matched radiofrequency irradiation for sensitivity enhancement of the I = 5/2 MQMAS experiment. These experiments exhibited certain selective line narrowing effects which were investigated theoretically.The fourth chapter extends the discussion of multiple quantum spectroscopy of quadrupolar nuclei to a mostly theoretical study of the feasibility of enhancing the resolution of nitrogen-14 NMR of large biomolecules in solution via double-quantum spectroscopy. The fifth chapter continues to extend the principles of multiple quantum NMR spectroscopy of quadrupolar nuclei to make analogies between experiments in NMR/nuclear quadrupolar resonance (NQR) and experiments in atomic/molecular optics (AMO). These analogies are made through the Hamiltonian and density operator formalism of angular momentum dynamics in the presence of electric and magnetic fields.The sixth chapter investigates the use of the macroscopic nuclear dipolar field to encode the NMR spectrum of an analyte nucleus indirectly in the magnetization of a sensor nucleus. This technique could potentially serve as an encoding

  19. Nuclear magnetic resonance studies of quadrupolar nuclei and dipolar field effects

    Energy Technology Data Exchange (ETDEWEB)

    Urban, Jeffry Todd [Univ. of California, Berkeley, CA (United States)

    2004-01-01

    Experimental and theoretical research conducted in two areas in the field of nuclear magnetic resonance (NMR) spectroscopy is presented: (1) studies of the coherent quantum-mechanical control of the angular momentum dynamics of quadrupolar (spin I > 1/2) nuclei and its application to the determination of molecular structure; and (2) applications of the long-range nuclear dipolar field to novel NMR detection methodologies.The dissertation is organized into six chapters. The first two chapters and associated appendices are intended to be pedagogical and include an introduction to the quantum mechanical theory of pulsed NMR spectroscopy and the time dependent theory of quantum mechanics. The third chapter describes investigations of the solid-state multiple-quantum magic angle spinning (MQMAS) NMR experiment applied to I = 5/2 quadrupolar nuclei. This work reports the use of rotary resonance-matched radiofrequency irradiation for sensitivity enhancement of the I = 5/2 MQMAS experiment. These experiments exhibited certain selective line narrowing effects which were investigated theoretically.The fourth chapter extends the discussion of multiple quantum spectroscopy of quadrupolar nuclei to a mostly theoretical study of the feasibility of enhancing the resolution of nitrogen-14 NMR of large biomolecules in solution via double-quantum spectroscopy. The fifth chapter continues to extend the principles of multiple quantum NMR spectroscopy of quadrupolar nuclei to make analogies between experiments in NMR/nuclear quadrupolar resonance (NQR) and experiments in atomic/molecular optics (AMO). These analogies are made through the Hamiltonian and density operator formalism of angular momentum dynamics in the presence of electric and magnetic fields.The sixth chapter investigates the use of the macroscopic nuclear dipolar field to encode the NMR spectrum of an analyte nucleus indirectly in the magnetization of a sensor nucleus. This technique could potentially serve as an

  20. Far from the intermediate nuclear field

    International Nuclear Information System (INIS)

    Dietrich, K.; Wagner, G.J.; Gregoire, C.; Campi, X.; Silvestre-Brac, B.; Platchkov, S.; Mayer, B.; Abgrall, Y.; Bohigas, O.; Grange, P.; Signarbieux, C.

    1988-01-01

    Pairing correlations in nuclear physics; the BCS state and quasi-particles; the layer model; collision effects on nuclear dynamics; the theory of cluster formation (application to nucleus fragmentation); short range correlations (few-particle systems); deuterium electron scattering; dibaryonic resonances; traditional and exotic hadron probes of nuclear structure; spectral fluctuations and chaotic motion; corrections to the intermediate nuclear field (nonrelativistic and other effects); and heavy nuclei splitting and nuclear superfluidity are introduced [fr

  1. Effective interactions and mean field theory: from nuclear matter to nuclei

    International Nuclear Information System (INIS)

    Cochet, B.

    2005-07-01

    The Skyrme force is a zero-range force that allows the construction of the mean field inside the nucleus in a simple way. Skyrme forces are reasonably predictive but some features of the infinite nuclear matter or the mass of heavy nuclei are not well computed. The aim of this work is to propose an expanded parametrization of the Skyrme force in order to improve its predictive power. The first part is dedicated to the construction of the expansion of the parametrization. We recall how the effective forces are linked to the nucleon-nucleon interaction then we show the limits of the standard Skyrme forces and we propose a relatively natural improvements based on the integration of spin and isospin instabilities. The second part deals with the validation of the model, first by describing infinite nuclear matter then by studying β-balanced nuclear matter which has enabled us to reproduce some features of neutron stars like mass and radius. The computation of properties of nuclei like binding energy, mass, radii depends strongly on the adjustment procedure. (A.C.)

  2. The nuclear equation of state in effective relativistic field theories and pion yields in heavy-ion collisions

    International Nuclear Information System (INIS)

    Schoenhofen, M.; Cubero, M.; Gering, M.; Sambataro, M.; Feldmeier, H.; Noerenberg, W.

    1989-06-01

    Within the framework of relativistic field theory for nucleons, deltas, scalar and vector mesons, a systematic study of the nuclear equation of state and its relation to pion yields in heavy-ion collisions is presented. Not the compressibility but the effective nucleon mass at normal nuclear density turns out to be the most sensitive parameter. Effects from vaccum fluctuations are well modelled within the mean-field no-sea approximation by self-interaction terms for the scalar meson field. Incomplete thermalization in the fireball may be the reason for the low pion yields observed in heavy-ion collisions. (orig.)

  3. Fields of nuclear power application

    International Nuclear Information System (INIS)

    Laue, H.J.

    1975-01-01

    The paper deals with nuclear power application in fields different from electricity generation, i.e. district heating, sea water desalination, coal gasification and nuclear splitting of water. (RW) [de

  4. Practical Calculational Scheme Implementing the Wilsonian RG Results for Nuclear Effective Field Theory Including Pions

    International Nuclear Information System (INIS)

    Kubo, H.; Harada, K.; Sakaeda, T.; Yamamoto, Y.

    2013-01-01

    On the basis of the Wilsonian renormalization group (WRG) analysis of nuclear effective field theory (NEFT) including pions, we propose a practical calculational scheme in which the short-distance part of one-pion exchange (S-OPE) is removed and represented as contact terms. The long-distance part of one-pion exchange (L-OPE) is treated as perturbation. The use of dimensional regularization (DR) for diagrams consisting only of contact interactions considerably simplifies the calculation of scattering amplitude and the renormalization group equations. NLO results for nucleon-nucleon elastic scattering in the S-waves are obtained and compared with experiments. A brief comment on NNLO calculations is given. (author)

  5. Equation of state of neutron-rich nuclear matter from chiral effective field theory

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, Norbert; Strohmeier, Susanne [Technische Universitaet Muenchen (Germany)

    2016-07-01

    Based on chiral effective field theory, the equation of state of neutron-rich nuclear matter is investigated systematically. The contributing diagrams include one- and two-pion exchange together with three-body terms arising from virtual Δ(1232)-isobar excitations. The proper expansion of the energy per particle, anti E(k{sub f},δ) = anti E{sub n}(k{sub f}) + δB{sub 1}(k{sub f}) + δ{sup 5/3}B{sub 5/3}(k{sub f}) + δ{sup 2}B{sub 2}(k{sub f}) +.., for the system with neutron density ρ{sub n} = k{sub f}{sup 3}(1-δ)/3π{sup 2} and proton density ρ{sub p} = k{sub f}{sup 3}δ/3π{sup 2} is performed analytically for the various interaction contributions. One observes essential structural differences to the commonly used quadratic approximation. The density dependent coefficient B{sub 1}(k{sub f}) turns out to be unrelated to the isospin-asymmetry of nuclear matter. The coefficient B{sub 5/3}(k{sub f}) of the non-analytical δ{sup 5/3}-term receives contributions from the proton kinetic energy and from the one- and two-pion exchange interactions. The physical consequences for neutron star matter are studied.

  6. Effects of CO2 injection and Kerogen Maturation on Low-Field Nuclear Magnetic Resonance Response

    Science.gov (United States)

    Prasad, M.; Livo, K.

    2017-12-01

    Low-field Nuclear Magnetic Resonance (NMR) is commonly used in petrophysical analysis of petroleum reservoir rocks. NMR experiments record the relaxation and polarization of in-situ hydrogen protons present in gaseous phases such as free-gas intervals and solution gas fluids, bulk fluid phases such as oil and aquifer intervals, and immovable fractions of kerogen and bitumen. Analysis of NMR relaxation spectra is performed to record how fluid composition, maturity, and viscosity change NMR experimental results. We present T1-T2 maps as thermal maturity of a water-saturated, sub-mature Woodford shale is increased at temperatures from 125 to 400 degrees Celsius. Experiments with applied fluid pressure in paraffinic mineral oil and DI water with varying fluid pH have been performed to mimic reservoir conditions in analysis of the relaxation of bulk fluid phases. We have recorded NMR spectra, T1-T2 maps, and fluid diffusion coefficients using a low-field (2 MHz) MagritekTM NMR. CO2 was injected at a pressure of 900 psi in an in house developed NMR pressure vessel made of torlon plastic. Observable 2D NMR shifts in immature kerogen formations as thermal maturity is increased show generation of lighter oils with increased maturity. CO2 injection leads to a decrease in bulk fluid relaxation time that is attributed to viscosity modification with gas presence. pH variation with increased CO2 presence were shown to not effect NMR spectra. From this, fluid properties have been shown to greatly affect NMR readings and must be taken into account for more accurate NMR reservoir characterization.

  7. Effect of nonlinearity of spin interaction with electromagnetic resonance field on characteristics of polarized nuclear target

    International Nuclear Information System (INIS)

    Vertij, A.A.; Gavrilov, S.P.; Shestopalov, V.P.

    1990-01-01

    Interaction of incident nuclear particle beam with J = 1/2 (neutrons) spin and (J = 1/2) protons with the target substance is considered. It is shown that neutron polarization at the target exit and neutron transparency (G) of the target depend significantly on incident wave amplitude level and physical parameter values which characterize the target, such as target temperature, resonator mirror reflection factor, number of spins interacting with the field, etc. Under interaction of neutrons with a target resonator which features a high mirror reflection factor and low losses for absorption which is not related to magnetic dipole absorption, a bistable response of neutron polarization and G manifests itself. 1 ref

  8. Turkey's status in nuclear field

    International Nuclear Information System (INIS)

    Aykol, F.; Oezkan, R.; Atila, B.; Hanguel, G.; Aksu, M.L.

    2002-01-01

    Full text: Turkey is a country with dynamic economic development and rapid population growth and nuclear energy is an integral part of these dynamics. Turkish Atomic Energy Authority (TAEA) is in charge of regulation and control of all activities related to nuclear field, including safety inspections and licensing. The TAEA is also responsible for the sensitive task of improving public awareness of nuclear technology which includes the use of nuclear power. Turkey's experience with nuclear power dates back to the 1960's, as the first nuclear research reactor started to operate in Istanbul in 1962. There were various plans for the introduction of nuclear power to the country. However the plans for the construction of the first nuclear power in the country were postponed for an indefinite period in 2000. In the wake of this decision TAEA initiated the activities to establish a nuclear policy in the country which includes creating the technical know-how and establishing new generation nuclear power plants in Turkey. The Authority is also responsible for the safe use of nuclear energy in medicine, agriculture, animal health, industry, food irradiation and in all kinds of research activities. The authority has carried or is currently continuing 12 National Technical Cooperation, 30 Research Contract, 21 Regional Europe ongoing IAEA projects and 31 State Planning Organization projects. There were 7571 radiological, 208 radiotherapy, 3792 industrial and 214 instruments licensed and registered by the Radiation Health and Safety Department of the Authority. We are in the opinion that developing a nuclear technology substructure in both Turkey and Turkish Countries will be of great benefit for the Euro-Asia region. We must emphasize that Turkey is the partner of all nonproliferation treaties and has no intention of using nuclear power for non peaceful purposes whatsoever

  9. Equations for effective nuclear fields taking account of 2p2h configurations

    International Nuclear Information System (INIS)

    Kamerdzhiev, S.P.

    1977-01-01

    Equations taking into account 1p1h and 2p2h configurations were obta+ned by means of effective fields in the nucleus. The consideration is restricted by the even-even Fermi system only with particle-hole interaction and by the first order with respect to an external field, which corresponds to the case of an even-even nucleus without pairing in a weak external field. The principal results of the investigation are as follows: a set of equations for effective fields V 2 and V 4 is obtained by the Green function method; the solutxon of the set makes it possible to consider 1p1h and 2p2h configurations consecutively and dispense with the Hartree-Fock self-consistence. The equations for V 2 and V 4 can be used to obtain quantum equations taking into account 2p2h configurations and their effect on 1p1h states. Allowance for integration regions far removed from the Fermi surface results in the appearance of the V 4 0 seed portion in the V 4 effective field. Taking into account 2p2h configurations at V 4 0 not equal to 0 changes the form of the seed multipole operator of a nucleus; a new term appears in the expression for transition probability. As a rule, the V 4 0 value was neglected in investigations dealing with the 2p2h configuration

  10. Tensor Fermi liquid parameters in nuclear matter from chiral effective field theory

    Science.gov (United States)

    Holt, J. W.; Kaiser, N.; Whitehead, T. R.

    2018-05-01

    We compute from chiral two- and three-body forces the complete quasiparticle interaction in symmetric nuclear matter up to twice nuclear matter saturation density. Second-order perturbative contributions that account for Pauli blocking and medium polarization are included, allowing for an exploration of the full set of central and noncentral operator structures permitted by symmetries and the long-wavelength limit. At the Hartree-Fock level, the next-to-next-to-leading order three-nucleon force contributes to all noncentral interactions, and their strengths grow approximately linearly with the nucleon density up to that of saturated nuclear matter. Three-body forces are shown to enhance the already strong proton-neutron effective tensor interaction, while the corresponding like-particle tensor force remains small. We also find a large isovector cross-vector interaction but small center-of-mass tensor interactions in the isoscalar and isovector channels. The convergence of the expansion of the noncentral quasiparticle interaction in Landau parameters and Legendre polynomials is studied in detail.

  11. Effective interaction for relativistic mean-field theories of nuclear structure

    International Nuclear Information System (INIS)

    Ai, H.B.; Celenza, L.S.; Harindranath, A.; Shakin, C.M.

    1987-01-01

    We construct an effective interaction, which when treated in a relativistic Hartree-Fock approximation, reproduces rather accurately the nucleon self-energy in nuclear matter and the Migdal parameters obtained via relativistic Brueckner-Hartree-Fock calculations. This effective interaction is constructed by adding Born terms, describing the exchange of pseudoparticles, to the Born terms of the Dirac-Hartree-Fock analysis. The pseudoparticles have relatively large masses and either real or imaginary coupling constants. (For example, exchange of a pseudo-sigma with an imaginary coupling constant has the effect of reducing the scalar attraction arising from sigma exchange while exchange of a pseudo-omega with an imaginary coupling constant has the effect of reducing the repulsion arising from omega exchange. The terms beyond the Born term in the case of pion exchange are well simulated by pseudo-sigma exchange with a real coupling constant.) The effective interaction constructed here may be used for calculations of the properties of finite nuclei in a relativistic Hartree-Fock approximation

  12. A review on the relativistic effective field theory with parameterized couplings for nuclear matter and neutron stars

    Energy Technology Data Exchange (ETDEWEB)

    Vasconcellos, C. A. Zen, E-mail: cesarzen@cesarzen.com [Instituto de Física, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves 9500, 91501-970, Porto Alegre (Brazil); International Center for Relativistic Astrophysics Network (ICRANet), Piazza della Repubblica 10, 65122 Pescara (Italy)

    2015-12-17

    Nuclear science has developed many excellent theoretical models for many-body systems in the domain of the baryon-meson strong interaction for the nucleus and nuclear matter at low, medium and high densities. However, a full microscopic understanding of nuclear systems in the extreme density domain of compact stars is still lacking. The aim of this contribution is to shed some light on open questions facing the nuclear many-body problem at the very high density domain. Here we focus our attention on the conceptual issue of naturalness and its role in shaping the baryon-meson phase space dynamics in the description of the equation of state (EoS) of nuclear matter and neutrons stars. In particular, in order to stimulate possible new directions of research, we discuss relevant aspects of a recently developed relativistic effective theory for nuclear matter within Quantum Hadrodynamics (QHD) with genuine many-body forces and derivative natural parametric couplings. Among other topics we discuss in this work the connection of this theory with other known effective QHD models of the literature and its potentiality in describing a new physics for dense matter. The model with parameterized couplings exhausts the whole fundamental baryon octet (n, p, Σ{sup −}, Σ{sup 0}, Σ{sup +}, Λ, Ξ{sup −}, Ξ{sup 0}) and simulates n-order corrections to the minimal Yukawa baryon couplings by considering nonlinear self-couplings of meson fields and meson-meson interaction terms coupled to the baryon fields involving scalar-isoscalar (σ, σ∗), vector-isoscalar (ω, Φ), vector-isovector (ϱ) and scalar-isovector (δ) virtual sectors. Following recent experimental results, we consider in our calculations the extreme case where the Σ{sup −} experiences such a strong repulsion that its influence in the nuclear structure of a neutron star is excluded at all. A few examples of calculations of properties of neutron stars are shown and prospects for the future are discussed.

  13. Views of a devil`s advocate -- Fundamental challenges to effective field theory treatments of nuclear physics

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, T.D.

    1998-04-01

    The physics goals of the effective field theory program for nuclear phenomena are outlined. It is pointed out that there are multiple schemes for implementing EFT and it is presently not clear if any of these schemes is viable. Most of the applications of effective field theory ideas have been on nucleon-nucleon scattering. It is argued that this is little more than curve fitting and that other quantities need to be calculated to test the ideas. It is shown that EFT methods work well for certain bound state properties of the deuteron electric form factor. However, it is also shown that this success depends sensitively on the fact that the majority of the probability of the deuteron`s wave function is beyond the range of the potential. This circumstance is special to the deuteron suggesting that it will be very difficult to achieve the same kinds of success for tightly bound nuclei.

  14. Radiation effects on materials in the near-field of nuclear waste repository. 1998 annual progress report

    International Nuclear Information System (INIS)

    Ewing, R.C.; Wang, L.M.

    1998-01-01

    'Site restoration activities at DOE facilities and the permanent disposal of nuclear waste generated at DOE facilities involve working with and within various types and levels of radiation fields. Once the nuclear waste is incorporated into a final form, radioactive decay will decrease the radiation field over geologic time scales, but the alpha-decay dose for these solids will still reach values as high as 10 18 alpha-decay events/gm in periods as short as 1,000 years. This dose is well within the range for which important chemical (e.g., increased leach rate) and physical (e.g., volume expansion) changes may occur in crystalline ceramics. Release and sorption of long-lived actinides (e.g., 237 Np) can provide a radiation exposure to backfill materials, and changes in important properties (e.g., cation exchange capacity) may occur. The objective of this research program is to evaluate the long term radiation effects in the materials in the near-field of a nuclear waste repository with accelerated experiments in the laboratory using energetic particles (electrons, ions and neutrons). Experiments on the microstructural evolution during irradiation of two important groups of materials, sheet silicates (e.g., clays) and zeolites (analcime), have been conducted; and studies of radiation-induced changes in chemical properties (e.g. cation exchange capacity) are underway. As of the mid-2nd year of the 3-year project, experiments on the microstructural evolution during irradiation of two important group of materials, sheet silicates (mica) and zeolites (analcime), have been conducted; and studies of radiation-induced changes in chemical properties (e.g., cation exchange capacity) are underway.'

  15. Nuclear axial current operators to fourth order in chiral effective field theory

    Energy Technology Data Exchange (ETDEWEB)

    Krebs, H., E-mail: hermann.krebs@rub.de [Institut für Theoretische Physik II, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Epelbaum, E., E-mail: evgeny.epelbaum@rub.de [Institut für Theoretische Physik II, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93016 (United States); Meißner, U.-G., E-mail: meissner@hiskp.uni-bonn.de [Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universität Bonn, D-53115 Bonn (Germany); Institut für Kernphysik, Institute for Advanced Simulation, and Jülich Center for Hadron Physics, Forschungszentrum Jülich, D-52425 Jülich (Germany); JARA - High Performance Computing, Forschungszentrum Jülich, D-52425 Jülich (Germany)

    2017-03-15

    We present the complete derivation of the nuclear axial charge and current operators as well as the pseudoscalar operators to fourth order in the chiral expansion relative to the dominant one-body contribution using the method of unitary transformation. We demonstrate that the unitary ambiguity in the resulting operators can be eliminated by the requirement of renormalizability and by matching of the pion-pole contributions to the nuclear forces. We give expressions for the renormalized single-, two- and three-nucleon contributions to the charge and current operators and pseudoscalar operators including the relevant relativistic corrections. We also verify explicitly the validity of the continuity equation.

  16. Testing the Standard Model and Fundamental Symmetries in Nuclear Physics with Lattice QCD and Effective Field Theory

    Energy Technology Data Exchange (ETDEWEB)

    Walker-Loud, Andre [College of William and Mary, Williamsburg, VA (United States)

    2016-10-14

    The research supported by this grant is aimed at probing the limits of the Standard Model through precision low-energy nuclear physics. The work of the PI (AWL) and additional personnel is to provide theory input needed for a number of potentially high-impact experiments, notably, hadronic parity violation, Dark Matter direct detection and searches for permanent electric dipole moments (EDMs) in nucleons and nuclei. In all these examples, a quantitative understanding of low-energy nuclear physics from the fundamental theory of strong interactions, Quantum Chromo-Dynamics (QCD), is necessary to interpret the experimental results. The main theoretical tools used and developed in this work are the numerical solution to QCD known as lattice QCD (LQCD) and Effective Field Theory (EFT). This grant is supporting a new research program for the PI, and as such, needed to be developed from the ground up. Therefore, the first fiscal year of this grant, 08/01/2014-07/31/2015, has been spent predominantly establishing this new research effort. Very good progress has been made, although, at this time, there are not many publications to show for the effort. After one year, the PI accepted a job at Lawrence Berkeley National Laboratory, so this final report covers just a single year of five years of the grant.

  17. Radiation effects on materials in the near-field of a nuclear waste repository. 1997 annual progress report

    International Nuclear Information System (INIS)

    Ewing, R.C.; Wang, L.M.

    1997-01-01

    'Sheet silicates (e.g. micas and clays) are important constituents of a wide variety of geological formations such as granite, basalt, and sandstone. Sheet silicates, particularly clays such as bentonite are common materials in near-field engineered barriers in high-level nuclear waste (HLW) repositories. This is because migration of radionuclides from an underground HLW repository to the geosphere may be significantly reduced by sorption of radionuclides (e.g., Pu, U and Np) onto sheet silicates (e.g., clays and micas) that line the fractures and pores of the rocks along groundwater flowpaths. In addition to surface sorption, it has been suggested that some sheet silicates may also be able to incorporate many radionuclides, such as Cs and Sr, in the inter-layer sites of the sheet structure. However, the ability of the sheet silicates to incorporate radionuclides and retard release and migration of radionuclides may be significantly affected by the near-field radiation due to the decay of fission products and actinides. for example, the unique properties of the sheet structures will be lost completely if the structure becomes amorphous due to irradiation effects. Thus, the study of irradiation effects on sheet-structures, such as structural damage and modification of chemical properties, are critical to the performance assessment of long-term repository behavior.'

  18. Strong-Field Modulated Diffraction Effects in the Correlated Electron-Nuclear Motion in Dissociating H2+

    International Nuclear Information System (INIS)

    He Feng; Becker, Andreas; Thumm, Uwe

    2008-01-01

    We show that the electronic dynamics in a molecule driven by a strong field is complex and potentially even counterintuitive. As a prototype example, we simulate the interaction of a dissociating H 2 + molecule with an intense infrared laser pulse. Depending on the laser intensity, the direction of the electron's motion between the two nuclei is found to follow or oppose the classical laser-electric force. We explain the sensitive dependence of the correlated electronic-nuclear motion in terms of the diffracting electronic momentum distribution of the dissociating two-center system. The distribution is dynamically modulated by the nuclear motion and periodically shifted in the oscillating infrared electric field

  19. Effects of nuclear vibration on the ionization process of H2+ in ultrashort intense laser field

    International Nuclear Information System (INIS)

    Phan, Ngoc-Loan; Nguyen, Ngoc-Ty; Truong, Tran-Chau

    2015-01-01

    By numerically solving the time-dependent Schrödinger equation, we calculate the ionization probability of a vibrating H 2 + exposed to ultrashort intense laser fields. The results show that the ionization probability increases by time and gets a saturation value. We also find that with some first vibration levels, the ionization probability from a higher vibration level is larger than that from a lower one. However, with higher vibration levels, at a certain level the ionization probability will take maximum and decrease with next levels. (paper)

  20. Relativistic approach to superfluidity in nuclear matter. Constructing effective pair wave function from relativistic mean field theory with a cutoff

    Energy Technology Data Exchange (ETDEWEB)

    Matsuzaki, M. [Fukuoka Univ. of Education, Dept. of Physics, Munakata, Fukuoka (Japan); Tanigawa, T.

    1999-08-01

    We propose a simple method to reproduce the {sup 1}S{sub 0} pairing properties of nuclear matter, which are obtained by a sophisticated model, by introducing a density-independent cutoff into the relativistic mean field model. This applies well to the physically relevant density range. (author)

  1. The nuclear N-body problem and the effective interaction in self-consistent mean-field methods

    International Nuclear Information System (INIS)

    Duguet, Thomas

    2002-01-01

    This work deals with two aspects of mean-field type methods extensively used in low-energy nuclear structure. The first study is at the mean-field level. The link between the wave-function describing an even-even nucleus and the odd-even neighbor is revisited. To get a coherent description as a function of the pairing intensity in the system, the utility of the formalization of this link through a two steps process is demonstrated. This two-steps process allows to identify the role played by different channels of the force when a nucleon is added in the system. In particular, perturbative formula evaluating the contribution of time-odd components of the functional to the nucleon separation energy are derived for zero and realistic pairing intensities. Self-consistent calculations validate the developed scheme as well as the derived perturbative formula. This first study ends up with an extended analysis of the odd-even mass staggering in nuclei. The new scheme allows to identify the contribution to this observable coming from different channels of the force. The necessity of a better understanding of time-odd terms in order to decide which odd-even mass formulae extracts the pairing gap the most properly is identified. These terms being nowadays more or less out of control, extended studies are needed to make precise the fit of a pairing force through the comparison of theoretical and experimental odd-even mass differences. The second study deals with beyond mean-field methods taking care of the correlations associated with large amplitude oscillations in nuclei. Their effects are usually incorporated through the GCM or the projected mean-field method. We derive a perturbation theory motivating such variational calculations from a diagrammatic point of view for the first time. Resuming two-body correlations in the energy expansion, we obtain an effective interaction removing the hard-core problem in the context of configuration mixing calculations. Proceeding to a

  2. Neutron-proton scattering at next-to-next-to-leading order in Nuclear Lattice Effective Field Theory

    Energy Technology Data Exchange (ETDEWEB)

    Alarcon, Jose Manuel [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Bonn (Germany); Thomas Jefferson National Accelerator Facility, Theory Center, Newport News, VA (United States); Du, Dechuan; Laehde, Timo A.; Li, Ning; Lu, Bing-Nan; Luu, Thomas [Institute for Advanced Simulation, Institut fuer Kernphysik, and Juelich Center for Hadron Physics, Forschungszentrum Juelich, Juelich (Germany); Klein, Nico [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Bonn (Germany); Lee, Dean [North Carolina State University, Department of Physics, Raleigh, NC (United States); Meissner, Ulf G. [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Bonn (Germany); Institute for Advanced Simulation, Institut fuer Kernphysik, and Juelich Center for Hadron Physics, Forschungszentrum Juelich, Juelich (Germany); Forschungszentrum Juelich, JARA - High Performance Computing, Juelich (Germany)

    2017-05-15

    We present a systematic study of neutron-proton scattering in Nuclear Lattice Effective Field Theory (NLEFT), in terms of the computationally efficient radial Hamiltonian method. Our leading-order (LO) interaction consists of smeared, local contact terms and static one-pion exchange. We show results for a fully non-perturbative analysis up to next-to-next-to-leading order (NNLO), followed by a perturbative treatment of contributions beyond LO. The latter analysis anticipates practical Monte Carlo simulations of heavier nuclei. We explore how our results depend on the lattice spacing a, and estimate sources of uncertainty in the determination of the low-energy constants of the next-to-leading-order (NLO) two-nucleon force. We give results for lattice spacings ranging from a = 1.97 fm down to a = 0.98 fm, and discuss the effects of lattice artifacts on the scattering observables. At a = 0.98 fm, lattice artifacts appear small, and our NNLO results agree well with the Nijmegen partial-wave analysis for S-wave and P-wave channels. We expect the peripheral partial waves to be equally well described once the lattice momenta in the pion-nucleon coupling are taken to coincide with the continuum dispersion relation, and higher-order (N3LO) contributions are included. We stress that for center-of-mass momenta below 100 MeV, the physics of the two-nucleon system is independent of the lattice spacing. (orig.)

  3. Renormalization (and power counting) of effective field theories for the nuclear force

    International Nuclear Information System (INIS)

    Timoteo, Varese S.; Szpigel, Sergio; Duraes, Francisco O.

    2011-01-01

    The most common scheme used to regularize the Lippman-Schwinger (LS) equation is to introduce a sharp or smooth regularizing function that suppresses the contributions from the potential matrix elements for momenta larger than a given cutoff scale, which separates high-energy/short-distance scales and low-energy/long-distance scales, thus eliminating the ultraviolet divergences in the momentum integrals. Then, one needs determine the strengths of the contact interactions, the so called low-energy constants (LEC), by fitting a set of low-energy scattering data. Once the LECs are fixed for a given cutoff, the LS equation can be solved to evaluate other observables. Such a procedure, motivated by Wilsons renormalization group, relies on the fundamental premise of EFT that physics at low-energy/long-distance scales is insensitive with respect to the details of the dynamics at high-energy/short-distance scales, i.e. the relevant high-energy/short- distance effects for describing the low-energy observables can be captured in the cutoff-dependent LECs. The NN interaction can be considered properly renormalized when the calculated observables are independent of the cutoff scale within the range of validity of the ChEFT or involves a small residual cutoff dependence due to the truncation of the chiral expansion. In the language of Wilsons renormalization group, this means that the LECs must run with the cutoff scale in such a way that the scattering amplitude becomes renormalization group invariant (RGI). Here we consider pionless EFT up to NNLO and chiral EFT up to NNLO and use a subtractive renormalization scheme to describe the NN scattering channels with. We fix the strength of the contact interactions at a reference scale, chosen to be the one the provides the best fit, and then evolve the driving terms with a non-relativistic Callan-Symanzik equation to slide the renormalization scale. By computing phase shift relative differences, we show that the method is RGI. We

  4. Single-particle potential of the Λ hyperon in nuclear matter with chiral effective field theory NLO interactions including effects of Y N N three-baryon interactions

    Science.gov (United States)

    Kohno, M.

    2018-03-01

    Adopting hyperon-nucleon and hyperon-nucleon-nucleon interactions parametrized in chiral effective field theory, single-particle potentials of the Λ and Σ hyperons are evaluated in symmetric nuclear matter and in pure neutron matter within the framework of lowest-order Bruckner theory. The chiral NLO interaction bears strong Λ N -Σ N coupling. Although the Λ potential is repulsive if the coupling is switched off, the Λ N -Σ N correlation brings about the attraction consistent with empirical data. The Σ potential is repulsive, which is also consistent with empirical information. The interesting result is that the Λ potential becomes shallower beyond normal density. This provides the possibility of solving the hyperon puzzle without introducing ad hoc assumptions. The effects of the Λ N N -Λ N N and Λ N N -Σ N N three-baryon forces are considered. These three-baryon forces are first reduced to normal-ordered effective two-baryon interactions in nuclear matter and then incorporated in the G -matrix equation. The repulsion from the Λ N N -Λ N N interaction is of the order of 5 MeV at normal density and becomes larger with increasing density. The effects of the Λ N N -Σ N N coupling compensate the repulsion at normal density. The net effect of the three-baryon interactions on the Λ single-particle potential is repulsive at higher densities.

  5. Occupational index for the nuclear energy field

    International Nuclear Information System (INIS)

    Barker, L.L.

    1979-01-01

    This study surveyed key nuclear employers to determine which journals and magazines were used to recruitment advertisement and to assess the credibility of advertisement as a recruitment technique. Volume of advertisement appearing in Physics Today was categorized and recorded for the years 1966 to 1977. Regression analysis was used to determine the relationships between the categories of advertisement and labor force information for physicists, physics instructors, and physicists in the nuclear field. The nuclear employers surveyed identified 166 journals in which they advertise for scientific, engineering, and technical personnel. Employers considered help-wanted advertising to be more effective and cost-effective than recruitment through state or private employment services. The employers as a group spent more money on help-wanted advertising in journals than on state and private employment services, recommendations from present staff, and professional meeting recruitment. Employers did spend more money on campus recruitment and help-wanted ads in newspapers than on help-wanted ads in journals. It was found that a help-wanted index for physicists in a disaggregated form could be constructed

  6. Internet map of the Hungarian nuclear field

    International Nuclear Information System (INIS)

    Besenyei, Elisabeth

    2001-01-01

    The increasing role of Internet in the dissemination of information cannot be questioned. The organisations dealing with public information have to face with this challenge. New methods and ways are needed in order to effectively use this opportunity. An effective communication requires certain knowledge on the characteristics of the target group. The present situation on the Internet use in Hungary has been studied by a number of public opinion polls. In Europe Hungary is the eleventh in the row concerning the population percentage of Internet users. At the same time it is hard to define the exact number as it is continuously increasing. From the public opinion polls it can be seen that about 49 % of active Internet users, about 37 percent seek for information on the Internet. The organisations playing role in nuclear field includes nuclear facilities, research institutes, regulatory bodies as well as civil associations. Almost all of them realised the importance of the appearance on the Internet and have their web site. Among the web-sites of the Hungarian nuclear facilities the new home page of the Paks NPP (www.npp.hu) is especially well designed and worth to visit. The Atomic Energy Research Institute operates the 10 MW Budapest Research Reactor. The main features of the reactor can be found on the web site of the institute (www.kfki.hu/~aekihp/). Information about the research possibilities of the training reactor of the Institute of Nuclear Techniques of the Technical University of Budapest is provided on the web site (www.reak.bme.hu). The web site of the Hungarian Atomic Energy Authority (www.haea.gov.hu) has been renewed recently. Certainly, the list of the web sites of the Hungarian organisations active in nuclear field cannot be complete as it is a continuously evolving area. Nevertheless one can see that the players realised the importance of the challenge given by the Internet. While considerable effort is needed to maintain and refresh the web site

  7. Improving nuclear regulatory effectiveness

    International Nuclear Information System (INIS)

    2001-01-01

    Ensuring that nuclear installations are operated and maintained in such a way that their impact on public health and safety is as low as reasonably practicable has been and will continue to be the cornerstone of nuclear regulation. In the past, nuclear incidents provided the main impetus for regulatory change. Today, economic factors, deregulation, technological advancements, government oversight and the general requirements for openness and accountability are leading regulatory bodies to review their effectiveness. In addition, seeking to enhance the present level of nuclear safety by continuously improving the effectiveness of regulatory bodies is seen as one of the ways to strengthen public confidence in the regulatory systems. This report covers the basic concepts underlying nuclear regulatory effectiveness, advances being made and future requirements. The intended audience is primarily nuclear safety regulators, but government authorities, nuclear power plant operators and the general public may also be interested. (author)

  8. Nuclear magnetic resonance and earth magnetic field

    International Nuclear Information System (INIS)

    Anon.

    1998-01-01

    Nuclear magnetic resonance concerns nuclei whose spin is different from 0. These nuclei exposed to a magnetic field is comparable to a peg top spinning around its axis while being moved by a precession movement called Larmor precession. This article presents an experiment whose aim is to reveal nuclear magnetism of nuclei by observing Larmor precession phenomena due to the earth magnetic field. The earth magnetic field being too weak, it is necessary to increase the magnetization of the sample during a polarization phase. First the sample is submitted to a magnetic field B perpendicular to the earth magnetic field B 0 , then B is cut off and the nuclei move back to their equilibrium position by executing a precession movement due to B 0 field. (A.C.)

  9. Managing human resources in the field of nuclear energy

    International Nuclear Information System (INIS)

    2009-01-01

    . This is expected to continue to be the case in the future. However, there is also expected to be greater worldwide mobility of nuclear personnel in the future, making human resources management more demanding, particularly in continuing to ensure that organizations in the nuclear field are attractive employers compared with other related choices. The guidance provided in this publication is intended to comprehensively address aspects of managing human resources in the nuclear field; these include ensuring that individuals have the competence needed to perform their assigned tasks, organizing work effectively, anticipating human resources needs, and monitoring and continually improving performance. This publication is applicable to the entire life cycle of nuclear facilities. This guide is intended for use by decision makers and senior managers responsible for the reliable supply of a competent workforce for the nuclear field, and also by line managers of nuclear facilities, who are responsible for the training, qualification and performance of their personnel, as well as for HR specialists in the nuclear field

  10. {sup 137}Cs in irrigation water and its effect on paddy fields in Japan after the Fukushima nuclear accident

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, Natsuki [Institute of Science and Technology, Niigata University, 8050 Ikarashi 2-nocho, Nishi-ku, Niigata 950-2181 (Japan); Obara, Hitomi [Oriental Consultants, Sumitomo Fudosan Nishi Shinjuku Bldg. No. 6, 3-12-1 Honmachi, Shibuya-ku, Tokyo 151-0071 (Japan); Ogasa, Marie; Miyazu, Susumu [Graduate School of Science and Technology, Niigata University, 8050 Ikarashi 2-nocho, Nishi-ku, Niigata 950-2181 (Japan); Harada, Naoki [Institute of Science and Technology, Niigata University, 8050 Ikarashi 2-nocho, Nishi-ku, Niigata 950-2181 (Japan); Nonaka, Masanori [Graduate School for Management of Technology, Niigata University, 8050 Ikarashi 2-nocho, Nishi-ku, Niigata 950-2181 (Japan)

    2014-05-01

    There is concern that radiocesium deposited in the environment after the accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) in March 2011 will migrate to paddy fields through hydrological pathways and cause serious and long-lasting damage to the agricultural activities. This study was conducted in the Towa region of Nihonmatsu in the northern part of Fukushima Prefecture, Japan, (1) to quantify {sup 137}Cs in stream water used to irrigate paddy fields by separating the dissolved and particulate components in water samples and then fractionating the particulate components bonded in different ways using a sequential extraction procedure, and (2) to determine the amounts of radiocesium newly added to paddy fields in irrigation water relative to the amounts of radiocesium already present in the fields from the deposition of atmospheric fallout immediately after the FDNPP accident. Three catchments were studied, and the {sup 137}Cs activity concentrations in stream water samples were 79–198 mBq L{sup −1} under stable runoff conditions and 702–13,400 Bq L{sup −1} under storm runoff conditions. The residual fraction (F4, considered to be non-bioavailable) was dominant, accounting for 59.5–82.6% of the total {sup 137}Cs activity under stable runoff conditions and 69.4–95.1% under storm runoff conditions. The {sup 137}Cs newly added to paddy fields in irrigation water only contributed 0.03–0.05% of the amount already present in the soil (201–348 kBq m{sup −2}). This indicates that the {sup 137}Cs inflow load in irrigation water is negligible compared with that already in the soil. However, the contribution from the potentially bioavailable fractions (F1 + F2 + F3) was one order of magnitude larger, accounting for 0.20–0.59%. The increase in the dissolved and soluble radiocesium fraction (F1) was especially large (3.0% to infinity), suggesting that radiocesium migration in irrigation water is increasing the accumulation of radiocesium in rice

  11. Remotely controlled cutting techniques in the field of nuclear decommissioning. Overview of effectively applied thermal cutting methods

    International Nuclear Information System (INIS)

    Bienia, H.; Klotz, B.

    2008-01-01

    This article describes 3 thermal cutting technologies that are effectively used in nuclear decommissioning projects: the autonomous flame cutting, the plasma arc cutting and the contact arc metal cutting. The autonomous flame cutting technology is based on a high pressure oxygen jet oxidizing the material in a small kerf. Not all metal types are appropriate for this technology. The plasma arc cutting, in contrast to the previous technology, uses an electronically induced plasma arc to melt a kerf in the material. Inside the plasma arc temperatures up to 30.000 K exist, so in theory, this temperature is sufficient to cut all materials. Contact arc metal cutting is a new thermal cutting technology for under-water cutting works. Here, a carbon blade cuts the components. An electric arc between the cutting blade and component melts a kerf into the material easing the cutting. This technology allows the cutting of complex structures with hollows. The applications in nuclear facility dismantling of these 3 cutting technologies and their limits are reported and their requirements (staff, investment) listed in a table. (A.C.)

  12. Human resources development in nuclear field in Japan

    International Nuclear Information System (INIS)

    Seki, Y.

    2007-01-01

    to nuclear field. There is a strong concern in the future supply of capable human resources in the nuclear field. It is feared that the knowledge and expertise necessary for securing safety of nuclear power plants and radiation application could not be sufficiently preserved and transferred to the next generation. In order to cope with the above situation, several proposals are being considered and some new systems are already being worked out. The joint establishment of a graduate school to educate the core members of nuclear engineers and regulatory officers are being considered with close cooperation between some universities and the new unified corporation to be formed by JAERI and JNC in FY2005. There are several similar plans to jointly establish graduate schools for the nuclear technology and sciences in the areas having various nuclear installations and universities. One of such plans is to establish a graduate school aiming to utilize strong neutron beam generated by the intense proton accelerator, J-PARC which is being constructed in Tokai-mura jointly with JAERI and KEK. Furthermore, there is also a plan to establish a Nuclear Education System Network (NesNET) to serve as the focal organization to enhance better cooperation and coordination of maintenance teams for NPPs, nuclear education and training centers and infrastructures in the industries, universities and national research institutions. In addition, a new qualification system for Professional Engineers in the Nuclear and Radiation Field has been established. This will become effective in 2004 as a national qualification to certify the professional level of nuclear and radiation engineers

  13. Using nitrogen-14 nuclear quadrupole resonance and electric field gradient information for the study of radiation effects

    International Nuclear Information System (INIS)

    Iselin, L.H.

    1995-12-01

    Nitrogen-14 nuclear quadrupole resonance (NQR) was used in an attempt to detect the effects of ionizing radiation on organic material. Previously reported resonances for urea were detected at 2,913.32 ± 0.01 kHz and 2,347.88 ± 0.08 kHz with associated T 2 * values 780 ± 20 micros and 523 ± 24 micros, respectively. The previously unreported ν - line for urea-d 4 was detected at 2,381 ± 0.04 Khz and used to determine accurately for the first time the values for the nuclear quadrupole coupling constant χ (3,548.74 ± 0.03 kHz) and the asymmetry parameter η (0.31571 ± 0.00007) for urea-d 4 . The inverse linewidth parameter T 2 * for ν + was measured at 928 ± 23 micros and for ν - at 721 ± 12 micros. Townes and Dailey analysis was performed and urea-d 4 exhibits a 0.004 increase in lone pair electronic density and a slight decrease in N-H bond electronic density, as compared to urea, probably due to the mass difference. A relationship is proposed, referred to as NQR linewidth analysis, between the dynamic spin relaxation times T 2 and T 2 * and the widths of the distributions of the NQR parameters. Linewidth analysis is presented as a tool for possible use in future NQR work in all area, not just radiation effects. This relationship is tested using sodium nitrite T 2 and T 2 * values for ν - and ν - as a function of temperature

  14. The effect of divalent ions on the elasticity and pore collapse of chalk evaluated from compressional wave velocity and low-field Nuclear Magnetic Resonance (NMR)

    DEFF Research Database (Denmark)

    Katika, Konstantina; Addassi, Mouadh; Alam, Mohammad Monzurul

    2015-01-01

    The effects of divalent ions on the elasticity and the pore collapse of chalk were studied through rock-mechanical testing and low-field Nuclear Magnetic Resonance (NMR) measurements. Chalk samples saturated with deionized water and brines containing sodium, magnesium, calcium and sulfate ions were...... subjected to petrophysical experiments, rock mechanical testing and low-field NMR spectroscopy. Petrophysical characterization involving ultrasonic elastic wave velocities in unconfined conditions, porosity and permeability measurements, specific surface and carbonate content determination and backscatter...... electron microscopy of the materials were conducted prior to the experiments. The iso-frame model was used to predict the bulk moduli in dry and saturated conditions from the compressional modulus of water-saturated rocks. The effective stress coefficient, as introduced by Biot, was also determined from...

  15. Superalloy applications in the nuclear field

    International Nuclear Information System (INIS)

    Ramanathan, L.V.; Padilha, A.F.

    1984-01-01

    The process conditions in the areas of nuclear fuel processing, fabrication, utilization, reprocessing and disposal are severe, demanding therefore the use of materials with high temperature mechanical strength and corrosion resistance. A number of refractory metal containing superalloys have found application in the diferrent areas of the nuclear field. The main aspects of the microstructure, strengthening mechanisms and corrosion resistance of 3 superalloys, namely Incoloy 825, Inconel 718 and Hastelloy C have been discussed. The role of the refractory metal elements in influencing the mechanical strength and corrosion resistance of superalloys has been emphasised. (Author) [pt

  16. Terminology standardisation in the nuclear engineering field

    International Nuclear Information System (INIS)

    Kraut, A.

    1987-01-01

    Terminological standardisation is made for the purpose of unambiguous understanding, at least among experts in a given field of knowledge. The author explains a number of criteria and aspects to be taken into account in the process of standardisation by referring to the work of the Terminology Committee on Nuclear Engineering. He discusses the word formation in a technical language and the features of standardised terminology. Accepted terminology is a main factor in all procedures concerning design, testing, and approval and licensing of nuclear facilities, and also is of importance in terms of economics. (HP) [de

  17. Momentum and density dependence of the nuclear mean field

    International Nuclear Information System (INIS)

    Behera, B.; Routray, T.R.

    1999-01-01

    The purpose of this is to analyse the momentum, density and temperature dependence of the mean field in nuclear matter derived from finite range effective interactions and to examine the influence of the functional form of the interaction on the high momentum behaviour of the mean field. Emphasis will be given to use very simple parametrizations of the effective interaction with a minimum number of adjustable parameters and yet capable of giving a good description of the mean field in nuclear matter over a wide range of momentum, density and temperature. As an application of the calculated equation of state of nuclear matter, phase transitions to quark-gluon plasma is studied where the quark phase is described by a zeroth order bag model equation of state

  18. Effects of nuclear electromagnetic pulse (EMP) on nuclear power plants

    International Nuclear Information System (INIS)

    Barnes, P.R.; Manweiler, R.W.; Davis, R.R.

    1977-09-01

    The electromagnetic pulse (EMP) from a high-altitude nuclear detonation consists of a transient pulse of high intensity electromagnetic fields. These intense fields induce current and voltage transients in electrical conductors. Although most nuclear power plant cables are not directly exposed to these fields, the attenuated EMP fields that propagate into the plant will couple some EMP energy to these cables. The report predicts the probable effects of the EMP transients that could be induced in critical circuits of safety-related systems. It was found that the most likely consequence of EMP for nuclear plants is an unscheduled shutdown. EMP could prolong the shutdown period by the unnecessary actuation of certain safety systems. In general, EMP could be a nuisance to nuclear power plants, but it is not considered a serious threat to plant safety

  19. Perturbation Expansion in Dynamical Nuclear Field Theory and Its Relation with Boson Expansion Theory : Nuclear Physics

    OpenAIRE

    Teruo, KISHIMOTO; Tetsuo, KAMMURI; Institute of Physics, University of Tsukuba; Department of Physics, Osaka University

    1990-01-01

    With the Dynamical Nuclear Field Theory (DNFT) in the Tamm-Dancoff representation we examine higher order corrections in the vibrational mode of a spherical nuclear system. Due to the effects of bubble diagrams, the perturbation expansion in terms of the unrenormalized coupling strength and boson energy fails at full self-consistency. On the other hand, it becomes applicable in the form of linked-cluster expansion when we use thses constants renormalized by the effect of bubble diagrams, in t...

  20. Nuclear spin Hall and Klein tunneling effects during oxidation with electric and magnetic field inductions in graphene.

    Science.gov (United States)

    Little, Reginald B; McClary, Felicia; Rice, Bria; Jackman, Corine; Mitchell, James W

    2012-12-14

    The recent observation of the explosive oxidation of graphene with enhancement for decreasing temperature and the requirements for synchronizing oxidants for collective oxidation-reduction (redox) reactions presented a chemical scenario for the thermal harvesting by the magnetic spin Hall Effect. More experimental data are presented to demonstrate such spin Hall Effect by determining the influence of spins of so-called spectator fermionic cations. Furthermore, the so-called spectator bosonic cations are discovered to cause a Klein tunneling effect during the redox reaction of graphene. The Na(+) and K(+), fermionic cations and the Mg(2+) and Ca(2+), bosonic cations were observed and compared under a variety of experimental conditions: adiabatic reactions with initial temperatures (18-22 °C); reactions toward infinite dilution; isothermal reactions under nonadiabatic conditions at low temperature of 18 °C; reactions under paramagnetic O(2) or diamagnetic N(2) atmospheres of different permeabilities; reactions in applied and no applied external magnetic field; and reactions toward excess concentrations of common and uncommon Na(+) and Mg(2+) cations. The observed reaction kinetics and dynamics under these various, diverse conditions are consistent with the spin Hall mechanism, energy harvesting and short time violation of Second Law of Thermodynamics for redox reactions of graphene by the Na(+)K(+) mixture and are consistent with the Klein tunnel mechanism for the redox reactions of graphene by the Mg(2+)Ca(2+) mixture. Mixed spin Hall and Klein tunnel mechanisms are discovered to slow and modulate explosive redox reactions. Such spin Hall Effect also gives explanation of recent tunneling of electrons through boron nitride.

  1. Harmonized technical standards in the nuclear field

    International Nuclear Information System (INIS)

    Carbone, Ferdinando

    1976-01-01

    The need was felt of harmonizing and gradually standardizing technical norms, from the well-known Anglo-Saxon type codes of practice to the equally well-known recommendations of the International Commission on Radiological Protection (ICRP). The latter provide the basis for the Euratom Directives (basic standards), which, following their adoption, were embodied in the national laws of community Member countries. ISO (International Standardization Organization) is active in the nuclear technical regulations field, in particular through its Committee ISO/TC 85 ''Nuclear Energy'' at international level and, in Italy, through the National Italian Unification Agency (UNI) and its Nuclear Unification Commission (UNICEN). At its XI plenary meeting this body, on the proposal of the Secretary-General, set up a Study Group to promote revision of the regulation in force and coordination between legislation and development of UNICEN standards, considered as a set of integrative industrial technical standards. CISDEN, the Italian Nuclear Energy Forum (FIEN) and other interested organizations have been invited to collaborate in this work. (N.E.A.)

  2. Quantum field theory and nuclear structure

    International Nuclear Information System (INIS)

    Celenza, L.S.; Goulard, B.; Shakin, C.M.

    1981-01-01

    We discuss recent successful calculations of the properties of nuclear matter within the context of theories exhibiting mass generation through spontaneous symmetry breaking. We start with the sigma model of Gell-Mann and Levy and introduce the nucleon mass (in a vacuum) in the usual manner. We relate the expectation value of the sigma field in a vacuum to a finite value of the scalar density. If the vacuum is now filled with nucleons (nuclear matter) the scalar density is increased and the new value for the nucleon mass must be determined. We exhibit the equation whose solution determines the new mass, and we also define a perturbative scheme for the determination of this mass. This scheme involves an expansion of the various quantities of the theory in terms of matrix elements calculated with positive- and negative-energy spinors parametrized with the vacuum mass. Although the decrease in the mass upon going from vacuum to nuclear matter at the equilibrium density is quite large (approx.400 MeV), we are still able to exhibit a small parameter which allows for a perturbative expansion of the binding energy and other observables. The leading term in such an expansion reproduces the approximation widely used in other calculations of the properties of nuclear matter. The truncation of the expansion at the leading term is inadequate and this fact accounts for the lack of success in previous calculations using the standard formalism. We proceed to make a transformation to the Weinberg Lagrangian retaining the fluctuating parts of the sigma field. We further make a small-oscillation approximation, dropping the nonlinear terms in this Lagrangian

  3. Japanese status-quo and our activities in the field of nuclear fuel recycle

    International Nuclear Information System (INIS)

    Sada, Masao; Imai, Osamu

    1983-01-01

    Nuclear energy is expected to take the place of current petroleum-base-energy in the near future. In order to effectively utilize the nuclear energy, nuclear fuel recycle system has to be established. The technology for reprocessing the spent fuel, which is a part of this recycle system, is very similar to the ones in chemical industry. Our company has been keeping its eyes on the field of such nuclear energy as one of the future promising businesses and recentrly established Nuclear Energy Department as a center for further expanding the business opportunity in the field of such spent fuel reprocessing as well as other fields of nuclear fuel recycle system. (author)

  4. Effective field theories

    International Nuclear Information System (INIS)

    Mack, G.; Kalkreuter, T.; Palma, G.; Speh, M.

    1992-05-01

    Effective field theories encode the predictions of a quantum field theory at low energy. The effective theory has a fairly low utraviolet cutoff. As a result, loop corrections are small, at least if the effective action contains a term which is quadratic in the fields, and physical predictions can be read straight from the effective Lagrangean. Methods will be discussed how to compute an effective low energy action from a given fundamental action, either analytically or numerically, or by a combination of both methods. Basically, the idea is to integrate out the high frequency components of fields. This requires the choice of a 'blockspin', i.e. the specification af a low frequency field as a function of the fundamental fields. These blockspins will be fields of the effective field theory. The blockspin need not be a field of the same type as one of the fundamental fields, and it may be composite. Special features of blockspin in nonabelian gauge theories will be discussed in some detail. In analytical work and in multigrid updating schemes one needs interpolation kernels A from coarse to fine grid in addition to the averaging kernels C which determines the blockspin. A neural net strategy for finding optimal kernels is presented. Numerical methods are applicable to obtain actions of effective theories on lattices of finite volume. The special case of a 'lattice' with a single site (the constraint effective potential) is of particular interest. In a higgs model, the effective action reduces in this case to the free energy, considered as a function of a gauge covariant magnetization. Its shape determines the phase structure of the theory. Its loop expansion with and without gauge fields can be used to determine finite size corrections to numerical data. (orig.)

  5. Large-scale nuclear structure calculations for spin-dependent WIMP scattering with chiral effective field theory currents

    OpenAIRE

    Klos, P.; Menéndez, J.; Gazit, D.; Schwenk, A.

    2013-01-01

    We perform state-of-the-art large-scale shell-model calculations of the structure factors for elastic spin-dependent WIMP scattering off 129,131Xe, 127I, 73Ge, 19F, 23Na, 27Al, and 29Si. This comprehensive survey covers the non-zero-spin nuclei relevant to direct dark matter detection. We include a pedagogical presentation of the formalism necessary to describe elastic and inelastic WIMP-nucleus scattering. The valence spaces and nuclear interactions employed have been previously used in nucl...

  6. Nonlinear mean field theory for nuclear matter and surface properties

    International Nuclear Information System (INIS)

    Boguta, J.; Moszkowski, S.A.

    1983-01-01

    Nuclear matter properties are studied in a nonlinear relativistic mean field theory. We determine the parameters of the model from bulk properties of symmetric nuclear matter and a reasonable value of the effective mass. In this work, we stress the nonrelativistic limit of the theory which is essentially equivalent to a Skyrme hamiltonian, and we show that most of the results can be obtained, to a good approximation, analytically. The strength of the required parameters is determined from the binding energy and density of nuclear matter and the effective nucleon mass. For realistic values of the parameters, the nonrelativistic approximation turns out to be quite satisfactory. Using reasonable values of the parameters, we can account for other key properties of nuclei, such as the spin-orbit coupling, surface energy, and diffuseness of the nuclear surface. Also the energy dependence of the nucleon-nucleus optical model is accounted for reasonably well except near the Fermi surface. It is found, in agreement with empirical results, that the Landau parameter F 0 is quite small in normal nuclear matter. Both density dependence and momentum dependence of the NN interaction, but especially the former, are important for nuclear saturation. The required scalar and vector coupling constants agree fairly well with those obtained from analyses of NN scattering phase shifts with one-boson-exchange models. The mean field theory provides a semiquantitative justification for the weak Skyrme interaction in odd states. The strength of the required nonlinear term is roughly consistent with that derived using a new version of the chiral mean field theory in which the vector mass as well as the nucleon mass is generated by the sigma-field. (orig.)

  7. Remotely controlled cutting techniques in the field of nuclear decommissioning. Overview of effectively applied thermal and non thermal cutting methods

    International Nuclear Information System (INIS)

    Bienia, H.

    2008-01-01

    Remote disassembly of radiologically burdened large components is among the most sophisticated and complex activities in the dismantling of nuclear installations. The required space for the technical equipment during the dismantling operations, especially for the removal of larger components is often an additional problem. Conventional cutting technologies like sawing with a disk saw or band saw require large and heavy frameworks as well as guiding systems with high rigidity. These solutions are expensive and sometimes not applicable. The essential question of all cutting and dismantling tasks is the physiological constitution of the component which will be dismantled. That means size, material and structure of the component. All these points are primarily technological questions. The last question is about the estimated costs of the used dismantling technology. Therefore following questions must be answered. How much are the investments for the cutting equipment itself and how much are the investments for the supporting equipment (e.g. necessary handling equipment)? Can I use this cutting equipment only for one special task or is it applicable for many tasks and therefore saves money because other cutting or dismantling technologies are dispensable? How long is the cutting time and what is the to control this technique required personnel? Four different cutting and dismantling technologies will be introduced and described. These four technologies differ in their principle of operation but all of them are used by cutting and dismantling tasks in nuclear power plants. (author)

  8. Effective quantum field theories

    International Nuclear Information System (INIS)

    Georgi, H.M.

    1993-01-01

    The most appropriate description of particle interactions in the language of quantum field theory depends on the energy at which the interactions are studied; the description is in terms of an ''effective field theory'' that contains explicit reference only to those particles that are actually important at the energy being studied. The various themes of the article are: local quantum field theory, quantum electrodynamics, new physics, dimensional parameters and renormalizability, socio-dynamics of particle theory, spontaneously broken gauge theories, scale dependence, grand unified and effective field theories. 2 figs

  9. Assessment of field training for nuclear operations personnel

    International Nuclear Information System (INIS)

    White, M.

    1995-08-01

    Training of station personnel is an important component of the safe operation of the nuclear generating station. On-the-job training (OJT) is an important component of training. The AECB initiated this project to develop a process to assess the effectiveness of OJT for field operators, and perform an initial trial of the developed process. This report describes the recommended process to assess the effectiveness of OJT for field operators, as well as the results of the initial assessment at Pickering Nuclear Generating Station. The assessment's conclusions included: (1) Ontario Hydro policies and procedures are generally consistent with industry guidelines requiring a systematic approach to training; (2) Pickering NGS field operator performance is not always consistent with documented station requirements and standards, nor industry guidelines and practices; and (3) The Pickering NGS field operator on-the-job training is not consistent with a systematic approach to training, a requirement recognized in Ontario Hydro's Policy NGD 113, and does not contribute to a high level of performance in field operator tasks. Recommendations are made regarding the use of the developed process for future assessments of on-the-job training at nuclear power plants. (author). 36 refs., 4 tabs., 3 figs

  10. Assessment of field training for nuclear operations personnel

    Energy Technology Data Exchange (ETDEWEB)

    White, M [Safety Management Services, Inc. (Canada)

    1995-08-01

    Training of station personnel is an important component of the safe operation of the nuclear generating station. On-the-job training (OJT) is an important component of training. The AECB initiated this project to develop a process to assess the effectiveness of OJT for field operators, and perform an initial trial of the developed process. This report describes the recommended process to assess the effectiveness of OJT for field operators, as well as the results of the initial assessment at Pickering Nuclear Generating Station. The assessment`s conclusions included: (1) Ontario Hydro policies and procedures are generally consistent with industry guidelines requiring a systematic approach to training; (2) Pickering NGS field operator performance is not always consistent with documented station requirements and standards, nor industry guidelines and practices; and (3) The Pickering NGS field operator on-the-job training is not consistent with a systematic approach to training, a requirement recognized in Ontario Hydro`s Policy NGD 113, and does not contribute to a high level of performance in field operator tasks. Recommendations are made regarding the use of the developed process for future assessments of on-the-job training at nuclear power plants. (author). 36 refs., 4 tabs., 3 figs.

  11. Nuclear energy and greenhouse effect

    International Nuclear Information System (INIS)

    Strub, R.A.

    1991-01-01

    The contribution of nuclear power plants against the greenhouse effects is evaluated, not only nuclear energy is unable to fight greenhouse effect increase but long life wastes endanger environment. 8 refs

  12. Psychological effects of nuclear warfare

    International Nuclear Information System (INIS)

    Mickley, G.A.

    1987-01-01

    This report is divided into five parts. (1) Discussion of the psychological milieu before a nuclear confrontation. (2) Acute psychological reactions to nuclear warfare (some of which may reflect, in part, direct radiogenic alteration of nervous system functions). (3) Chronic psychological effects of a nuclear confrontation. (4) Issues concerning treatment of these psychological changes. (5) Prevention of adverse psychological reactions to nuclear warfare

  13. Magnetic field coil in nuclear fusion device

    International Nuclear Information System (INIS)

    Yamaguchi, Mitsugi; Takano, Hirohisa.

    1975-01-01

    Object: To provide an electrical-insulatively stabilized magnetic field coil in nuclear fusion device, restraining an increase in voltage when plasma current is rapidly changed. Structure: A magnetic field coil comprises coils arranged coaxial with respective vacuum vessels, said coils being wound in positive and reverse polarities so as to form a vertical magnetic field within the plasma. The coils of the positive polarity are arranged along the vacuum vessel inside of an axis vertical in section of the annular plasma and are arranged symmetrically up and down of a horizontal axis. On the other hand, the coils of the reverse polarity are arranged along the vacuum vessel outside of a vertical axis and arranged symmetrically up and down of the horizontal axis. These positive and reverse polarity coils are alternately connected in series, and lead portions of the coils are connected to a power source by means of connecting wires. In this case, lead positions of the coils are arranged in one direction, and the connecting wires are disposed in closely contact relation to offset magnetic fields formed by the connecting wires each other. (Kawakami, Y.)

  14. Self-consistent mean-field models for nuclear structure

    International Nuclear Information System (INIS)

    Bender, Michael; Heenen, Paul-Henri; Reinhard, Paul-Gerhard

    2003-01-01

    The authors review the present status of self-consistent mean-field (SCMF) models for describing nuclear structure and low-energy dynamics. These models are presented as effective energy-density functionals. The three most widely used variants of SCMF's based on a Skyrme energy functional, a Gogny force, and a relativistic mean-field Lagrangian are considered side by side. The crucial role of the treatment of pairing correlations is pointed out in each case. The authors discuss other related nuclear structure models and present several extensions beyond the mean-field model which are currently used. Phenomenological adjustment of the model parameters is discussed in detail. The performance quality of the SCMF model is demonstrated for a broad range of typical applications

  15. Regional cooperation based on multilateral international agreements in nuclear field

    International Nuclear Information System (INIS)

    Valcic, I.

    1996-01-01

    Multilateral international agreements have defined the framework of behavior and cooperation in various fields and aspects of peaceful use of nuclear energy. Thus, obligations have been defined in the following areas: nonproliferation of nuclear weapons, physical protection of nuclear material, liability for nuclear damage, nuclear safety, early notification about a nuclear accident and assistance in case of nuclear accident. Obligations regarding radioactive waste management should be defined soon. This paper gives a review of obligations from particular agreements with a special emphasis on those which are being realized through mutual cooperation of concerned countries and are important for safe use of nuclear energy. (author)

  16. Pulsed magnetic field generation suited for low-field unilateral nuclear magnetic resonance systems

    Science.gov (United States)

    Gaunkar, Neelam Prabhu; Selvaraj, Jayaprakash; Theh, Wei-Shen; Weber, Robert; Mina, Mani

    2018-05-01

    Pulsed magnetic fields can be used to provide instantaneous localized magnetic field variations. In presence of static fields, pulsed field variations are often used to apply torques and in-effect to measure behavior of magnetic moments in different states. In this work, the design and experimental performance of a pulsed magnetic field generator suited for low static field nuclear magnetic resonance (NMR) applications is presented. One of the challenges of low bias field NMR measurements is low signal to noise ratio due to the comparable nature of the bias field and the pulsed field. Therefore, a circuit is designed to apply pulsed currents through an inductive load, leading to generation of pulsed magnetic fields which can temporarily overpower the effect of the bias field on magnetic moments. The designed circuit will be tuned to operate at the precession frequency of 1H (protons) placed in a bias field produced by permanent magnets. The designed circuit parameters may be tuned to operate under different bias conditions. Therefore, low field NMR measurements can be performed for different bias fields. Circuit simulations were used to determine design parameters, corresponding experimental measurements will be presented in this work.

  17. Radiation Effects in Nuclear Ceramics

    Directory of Open Access Journals (Sweden)

    L. Thomé

    2012-01-01

    Full Text Available Due to outstanding physicochemical properties, ceramics are key engineering materials in many industrial domains. The evaluation of the damage created in ceramics employed in radiative media is a challenging problem for electronic, space, and nuclear industries. In this latter field, ceramics can be used as immobilization forms for radioactive wastes, inert fuel matrices for actinide transmutation, cladding materials for gas-cooled fission reactors, and structural components for fusion reactors. Information on the radiation stability of nuclear materials may be obtained by simulating the different types of interactions involved during the slowing down of energetic particles with ion beams delivered by various types of accelerators. This paper presents a review of the radiation effects occurring in nuclear ceramics, with an emphasis on recent results concerning the damage accumulation processes. Energetic ions in the KeV-GeV range are used to explore the nuclear collision (at low energy and electronic excitation (at high energy regimes. The recovery by electronic excitation of the damage created by ballistic collisions (SHIBIEC process is also addressed.

  18. Integrated management systems in the nuclear field

    International Nuclear Information System (INIS)

    Beckmerhagen, I.A.; Berg, H.P.; Karapetrovic, S.V.; Willborn, W.O.

    2005-01-01

    In the last years several internationally accepted standards such as the ISO 9000 and ISO 14000 series and other function-specific management systems standards have been developed. At the same time, it has become imperative for organisations to continuously improve their overall quality, environmental and safety performance. Therefore, the need to create integrated management systems is of growing importance to enable an easier handling of the different management systems. This paper has two main objectives. The first one is to address the key issues in the underlying theory of integrated management systems including benefits and limits, the second one is to illustrate the importance of an integrated (in particular safety) management system and the experience feedback providing examples from different areas and different organisations in the nuclear field. (orig.)

  19. A study on the application of two-dosimeter algorithm to estimate the effective dose in an inhomogeneous radiation field at Korean Nuclear Power Plants

    International Nuclear Information System (INIS)

    Kim, Hee Geun; Kong, Tae Young

    2008-01-01

    In Korean Nuclear Power Plants (NPPs), two ThermoLuminescent Dosimeters (TLD) were provided to workers who work in an inhomogeneous radiation field; one on the chest and the other on the head. In this way, the effective dose for radiation workers at NPPs was determined by the high deep dose between two radiation dose from these TLDs. This represented a conservative method of evaluating the degree of exposure to radiation. In this study, to prevent the overestimation of the effective dose, field application experiments were implemented using two-dosimeter algorithms developed by several international institutes for the selection of an optimal algorithm. The algorithms used by the Canadian Ontario Power Generation (OPG) and American ANSI HPS N13.41, NCRP (55/50), NCRP (70/30), EPRI (NRC), Lakshmanan, and Kim (Texas A and M University) were extensively analyzed as two-dosimeter algorithms. In particular, three additional TLDs were provided to radiation workers who wore them on the head, chest, and back during maintenance periods, and the measured value were analyzed. The results found no significant differences among the calculated effective doses, apart from Lakshmanan's algorithm. Thus, this paper recommends the NCRP(55/50) algorithm as an optimal two-dosimeter algorithm in consideration of the solid technical background of NCRP and the convenience of radiation works. In addition, it was determined that a two-dosimeter is provided to a single task which is expected to produce a dose rate of more than 1 mSv/hr, a difference of dose rates depending on specific parts of the body of more than 30%, and an exposure dose of more than 2 mSv

  20. In-field analysis and assessment of nuclear material

    International Nuclear Information System (INIS)

    Morgado, R.E.; Myers, W.S.; Olivares, J.A.; Phillips, J.R.; York, R.L.

    1996-01-01

    Los Alamos National Laboratory has actively developed and implemented a number of instruments to monitor, detect, and analyze nuclear materials in the field. Many of these technologies, developed under existing US Department of Energy programs, can also be used to effectively interdict nuclear materials smuggled across or within national borders. In particular, two instruments are suitable for immediate implementation: the NAVI-2, a hand-held gamma-ray and neutron system for the detection and rapid identification of radioactive materials, and the portable mass spectrometer for the rapid analysis of minute quantities of radioactive materials. Both instruments provide not only critical information about the characteristics of the nuclear material for law-enforcement agencies and national authorities but also supply health and safety information for personnel handling the suspect materials

  1. Application of plasma technology to nuclear engineering fields

    International Nuclear Information System (INIS)

    Suzuki, Masaaki; Akatsuka, Hiroshi

    1996-01-01

    In order to discuss about the application of the plasma technology to nuclear engineering fields, we mention two subjects, the oxygenation of metal chloride waste by oxygen plasma and the characterization of fine particles generated in the plasma process. Through the experimental results of two subjects, both of the advantage and the disadvantage of the plasma technology and their characteristics are shown and discussed. The following conclusions are obtained. The reactive plasma is effective to oxygenate the chloride wastes. The particle generation which is one of the disadvantages must not be specialized and its characteristics can be estimated. Consequently, the plasma technology should be applicable to nuclear engineering fields adopting its advantage and overcoming its disadvantage. (author)

  2. Neutron albedo effects of underground nuclear explosion

    International Nuclear Information System (INIS)

    Yang Bo; Ying Yangjun; Li Jinhong; Bai Yun

    2013-01-01

    The neutron field distribution is affected by the surrounding medium in the underground nuclear explosion. It will influence the radiation chemical diagnosis. By Monte Carlo simulation, the fuel burnup induced by device and neutron albedo was calculated. The analysis method of albedo effect on radiation chemical diagnosis result under special environment was proposed. Neutron albedo should be considered when capture reaction burnup fraction is used, and then correct analysis can be carried out on the nuclear device.The neutron field distribution is affected by the surrounding medium in the underground nuclear explosion. It will influence the radiation chemical diagnosis. By Monte Carlo simulation, the fuel burnup induced by device and neutron albedo was calculated. The analysis method of albedo effect on radiation chemical diagnosis result under special environment was proposed. Neutron albedo should be considered when capture reaction burnup fraction is used, and then correct analysis can be carried out on the nuclear device. (authors)

  3. Romanian regulatory requirements on nuclear field specific education needs

    International Nuclear Information System (INIS)

    Biro, L.; Velicu, O.

    2004-01-01

    This work is intended as a general presentation of the educational system and research field, with reference to nuclear sciences, and the legal system, with reference to requirements established by the regulatory body for the professional qualification and periodic training of personnel involved in different activities in the nuclear field. Thus, part 2 and 3 of the work present only public information regarding the education in nuclear sciences and nuclear research in Romania; in part 4 the CNCAN requirements for the personnel training, specific to nuclear activities are slightly detailed; part 5 consists of few words about the public information activities in Romania; and part 6 tries to draw a conclusion. (authors)

  4. Kazakhstan innovation projects in nuclear technologies field

    International Nuclear Information System (INIS)

    Shkol'nik, V.S.; Tukhvatulin, Sh.T.

    2005-01-01

    At present in the Republic of Kazakhstan in preparation and realization stage there are several innovation projects related with use of advanced nuclear technologies. Projects are as follows: 'Implementation of Kazakhstan thermonuclear reactor tokamak (KTM)'; 'Implementation at the L.N. Gumilev Eurasian National University the inter-disciplinary research complex on the heavy ions accelerator base'; 'Development of the Technological Park 'Nuclear Technologies Center in Kurchatov city'; 'Development the first in the Central-Asian region Center of Nuclear Medicine and Biophysics'. The initiator and principal operator of these projects is the National Nuclear Center of the Republic of Kazakhstan

  5. Effective quantum field theories

    International Nuclear Information System (INIS)

    Georgi, H.M.

    1989-01-01

    Certain dimensional parameters play a crucial role in the understanding of weak and strong interactions based on SU(2) x U(1) and SU(3) symmetry group theories and of grand unified theories (GUT's) based on SU(5). These parameters are the confinement scale of quantum chromodynamics and the breaking scales of SU(2) x U(1) and SU(5). The concepts of effective quantum field theories and renormalisability are discussed with reference to the economics and ethics of research. (U.K.)

  6. Biological effects of nuclear weapons

    International Nuclear Information System (INIS)

    Frischauf, H.

    1983-01-01

    Prompt and delayed biological effects of nuclear weapons are discussed. The response to excess pressure on man is estimated, the acute radiation syndrome caused by different radiation doses and cancerogenous and genetic effects are described. Medical care after a nuclear explosion would be difficult and imperfect. (M.J.)

  7. Field vibration test of principal equipment of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Shiraki, Kazuhiro; Fujita, Katsuhisa; Kajimura, Motohiko; Ikegami, Yasuhiko; Hanzawa, Katsumi; Sakai, Yoshiyuki; Kokubo, Eiji; Igarashi, Shigeru

    1984-09-01

    Japan is one of the most earthquake-stricken countries in the world, and demands for aseismic design have become severer recently. In a nuclear power plant in particular, consisting of a reactor vessel and other facilities dealing with a radioactive substance in some form or other, it is essential from the standpoint of safety to eliminate any possibility of radioactive hazards for the local public, and the employees at the plant as well, if these facilities are struck by an earthquake. This paper is related to the reactor vessel, reactor primary cooling equipment and piping system and important general piping as examples of important facilities of a nuclear power plant, and discusses vibration tests of an actual plant in the field from the standpoint of enhancing the aseismic safety of the Mitsubishi PWR nuclear power plant. Especially concerning vibration test technology, the effects in the evaluation of aseismic safety and its limits are studied to prove how it contributes to the enhancement of the reliability of aseismic design of nuclear power plants.

  8. Nuclear matter in relativistic mean field theory with isovector scalar meson.

    Energy Technology Data Exchange (ETDEWEB)

    Kubis, S.; Kutschera, M. [Institute of Nuclear Physics, Cracow (Poland)

    1996-12-01

    Relativistic mean field (RMF) theory of nuclear matter with the isovector scalar mean field corresponding to the {delta}-meson [a{sub 0}(980)] is studied. While the {delta}-meson field vanishes in symmetric nuclear matter, it can influence properties of asymmetric nuclear matter in neutron stars. The RMF contribution due to {delta}-field to the nuclear symmetry energy is negative. To fit the empirical value, E{sub s}{approx}30 MeV, a stronger {rho}-meson coupling is required than in absence of the {delta}-field. The energy per particle of neutron star matter is than larger at high densities than the one with no {delta}-field included. Also, the proton fraction of {beta}-stable matter increases. Splitting of proton and neutron effective masses due to the {delta}-field can affect transport properties of neutron star matter. (author). 4 refs, 6 figs.

  9. Nuclear matter in relativistic mean field theory with isovector scalar meson

    International Nuclear Information System (INIS)

    Kubis, S.; Kutschera, M.

    1996-12-01

    Relativistic mean field (RMF) theory of nuclear matter with the isovector scalar mean field corresponding to the δ-meson [a 0 (980)] is studied. While the δ-meson field vanishes in symmetric nuclear matter, it can influence properties of asymmetric nuclear matter in neutron stars. The RMF contribution due to δ-field to the nuclear symmetry energy is negative. To fit the empirical value, E s ∼30 MeV, a stronger ρ-meson coupling is required than in absence of the δ-field. The energy per particle of neutron star matter is than larger at high densities than the one with no δ-field included. Also, the proton fraction of β-stable matter increases. Splitting of proton and neutron effective masses due to the δ-field can affect transport properties of neutron star matter. (author). 4 refs, 6 figs

  10. Chemical effects of nuclear transformations

    Energy Technology Data Exchange (ETDEWEB)

    Bulbulian, S

    1982-06-01

    A brief survey of the present state of knowledge on the chemical effects of nuclear transformations is presented. The recoil energy produced by these transformations in the nuclide is often sufficiently high to disrupt the chemical ligands between these particular atoms affected by the nuclear transformations, while the rest of their molecules. It also contains a discussion of the different annealing processes that produce the cancellation of the chemical change produced by the nuclear transformation.

  11. Nuclear resonance apparatus including means for rotating a magnetic field

    International Nuclear Information System (INIS)

    Sugimoto, H.

    1983-01-01

    A nuclear magnetic resonance apparatus including magnet apparatus for generating a homogeneous static magnetic field between its magnetic poles, shims of a magnetic substance mounted on the magnetic poles to apply a first gradient magnetic field intensity distribution in a direction orthogonal as to the direction of line of magnetic force of the static magnetic field, gradient magnetic field generating electromagnetic apparatus for generating a second gradient magnetic field having a gradient magnetic field intensity distribution in superimposition with the static magnetic field and for changing the magnetic field gradient of the first gradient magnetic field, an oscillator for generating an oscillating output having a frequency corresponding to the nuclear magnetic resonance condition of an atomic nucleus to be measured, a coil wound around a body to be examined for applying the output of said oscillator as electromagnetic waves upon the body, a receiver for detecting the nuclear magnetic resonance signals received by the coil, a gradient magnetic field controller making a magnetic field line equivalent to the combined gradient magnetic fields and for rotating the line along the section of the body to be examined by controlling said gradient magnetic field generating electromagnetic apparatus and devices for recording the nuclear magnetic resonance signals, for reconstructing the concentration distribution of the specific atomic nuclei in the section of the body, and a display unit for depicting the result of reconstruction

  12. Holographic effective field theories

    Energy Technology Data Exchange (ETDEWEB)

    Martucci, Luca [Dipartimento di Fisica ed Astronomia “Galileo Galilei' , Università di Padova,and INFN - Sezione di Padova, Via Marzolo 8, I-35131 Padova (Italy); Zaffaroni, Alberto [Dipartimento di Fisica, Università di Milano-Bicocca,and INFN - Sezione di Milano-Bicocca, I-20126 Milano (Italy)

    2016-06-28

    We derive the four-dimensional low-energy effective field theory governing the moduli space of strongly coupled superconformal quiver gauge theories associated with D3-branes at Calabi-Yau conical singularities in the holographic regime of validity. We use the dual supergravity description provided by warped resolved conical geometries with mobile D3-branes. Information on the baryonic directions of the moduli space is also obtained by using wrapped Euclidean D3-branes. We illustrate our general results by discussing in detail their application to the Klebanov-Witten model.

  13. Higgs Effective Field Theories

    CERN Document Server

    2016-01-01

    The main focus of this meeting is to present new theoretical advancements related to effective field theories, evaluate the impact of initial results from the LHC Run2, and discuss proposals for data interpretation/presentation during Run2. A crucial role of the meeting is to bring together theorists from different backgrounds and with different viewpoints and to extend bridges towards the experimental community. To this end, we would like to achieve a good balance between senior and junior speakers, enhancing the visibility of younger scientists while keeping some overview talks.

  14. Nuclear explosions and their effects

    Energy Technology Data Exchange (ETDEWEB)

    1958-01-01

    A brief historical background is given of the development of the atomic bomb. Also included is an account of the Hiroshima-Nagasaki bombing, plus some information on the testing and production of nuclear weapons by the United States, United Kingdom, and Russia. More detailed consideration is given to the following: the scientific principles of fission and fusion explosions; the energy released in fission and the radioactivity of fission products; blast, thermal, and radiologicalal effects of nuclear explosions; long-term radiological hazards from fall-out; and genetic effects of nuclear explosions. A brief account is given of the fission chain process, the concept of critical size, and the principles of implosion as applied to nuclear explosions. Limited information is presented on the controlled release of thermonuclear energy and catalyzed fusion reaction. Discussions are included on dose rates from radiation sources inside and outside the body, the effect of nuclear explosions on the weather, and the contamination of fish and marine organisms.

  15. Effects of nuclear war on health and health services

    International Nuclear Information System (INIS)

    1990-01-01

    This report reviews the findings since 1987 in the field of research related to the possible impact of nuclear war and nuclear explosions on health and health services. An annex contains the finding and conclusions of a 1989 United Nations study on the climatic and other effects of nuclear war. 1 tab

  16. Educational Approach to Maintain a Suitable Knowledge and Expertise in Nuclear Field: Case of Morocco

    International Nuclear Information System (INIS)

    Choukri, A.; Hakam, O.K.

    2016-01-01

    Full text: Nuclear knowledge management has become an increasingly important element of the nuclear sector in recent years, resulting from a number of challenges and trends. The development of any national nuclear energy programme is dependent on the successful development of the workforce, through a sustainable nuclear educational and training programme supported by government and industry. Morocco has continuously provided educational programmes in nuclear field at its universities since 1967. These academic programmes focused on nuclear sciences, nuclear engineering, radiation protection, etc., and were intended to undergraduate and postgraduate students. Nuclear techniques have known also an increased contribution to medicine, agriculture, industry and research in Morocco. Some educational and training programmes have been elaborated to develop human resources needed in different domains. University of Ibn Tofail, has launched, since september 2010, a national master’s programme in the field of nuclear sciences which aims to provide knowledge directly used in the various sectors using nuclear techniques and requiring radiation protection, nuclear safety and security including notions on nuclear knowledge management. For an effective management of nuclear knowledge, the educational didactic has been improved increasingly. Some new techniques, materiel and styles have been employed such as demonstrations, group exercises, e-learning, visio-conferences. (author

  17. Nuclear war effects studied

    Science.gov (United States)

    Widespread starvation resulting from changes in climate in the aftermath of a large-scale nuclear war could kill far more people than would the bombs themselves. That prediction was made in a recent study by the Scientific Committee on Problems of the Environment (SCOPE), an a rm of the International Council of Scientific Unions (ICSU). “Noncombatant and combatant countries alike” would risk mass starvation; SCOPE predicted that all told, 2.5 billion people could die as a result of crop failures and breakdowns in food distribution after a nuclear war.

  18. The effectiveness and development trend of nuclear third party liability insurance in the nuclear risk management

    International Nuclear Information System (INIS)

    Wang Pei

    2010-01-01

    Nuclear power considerably benefited mankind since it was utilized peaceably. The cleanness, safety and high efficiency of nuclear power were gradually known and recognized by the public. However at the same time, nuclear power had produced significant accident and consequently caused severe aftereffects during its utilization. Therefore, effective management of nuclear risk and reducing its accident probability are the social responsibilities of every nuclear nation. From the insurance point of view, this document analyzes the validity and development trends of nuclear third party insurance in nuclear risk management. It also introduces effectual experience in this field from nuclear insurance developed countries. This document discusses the necessity of consummating nuclear third party insurance under the aggressive development situation of nuclear power in our country. (author)

  19. The supervisions in the field develop nuclear professionals

    International Nuclear Information System (INIS)

    Fernandez de la Casa, M.; Buedo, J. L.; Gonzalez, F.

    2015-01-01

    In 2011 Cofrentes Nuclear Power Plants began a training program for improving the supervision of managers in the field: the effort done not only has improved the quality of supervisions but also has defined a way to reinforce behavior expectations of Cofrentes Nuclear Power Plant. (Author)

  20. Skills for development of nuclear professional for field observations

    International Nuclear Information System (INIS)

    Alvarez Gutierrez, N.; Buedo, J. L.

    2012-01-01

    The presence of commanders in the field is a growing need in the nuclear sector. The education, training and monitoring of the leaders involved in monitoring programs, allow have a group of nuclear professionals that offer specific and useful feedback and helps improve plant safety.

  1. A study on enhancing policy transparency in the nuclear field

    Energy Technology Data Exchange (ETDEWEB)

    Cheon, S. W. [Korea Institute for National Unification, Seoul (Korea)

    2000-11-01

    Enhancing transparency in the nuclear field is a pending issue for the South Korea's nuclear community. International suspicions and mistrust of ROK's nuclear activities have been obstacles to the developments of South Korea's nuclear industry. South Korea's efforts have not been sufficient enough to ensure international community that its nuclear program will be used solely for peaceful purposes. Therefore, the purpose of this study is to conduct a positive and creative research on the issue of transparency and provide policy options that are conducive to developing of South Korea's nuclear industry. Based on an in-depth study on transparency of national policies, this study presents a package of detail policy measures that can contribute to enhancing transparency in the nuclear filed. 75 refs., 2 tabs. (Author)

  2. Instability in relativistic mean-field theories of nuclear matter

    International Nuclear Information System (INIS)

    Friman, B.L.; Henning, P.A.

    1988-01-01

    We investigate the stability of the nuclear matter ground state with respect to small-perturbations of the meson fields in relativistic mean-field theories. The popular σ-ω model is shown to have an instability at about twice the nuclear density, which gives rise to a new ground state with periodic spin alignment. Taking into account the contributions of the Dirac sea properly, this instability vanishes. Consequences for relativistic heavy-ion-collisions are discussed briefly. (orig.)

  3. Instability in relativistic mean-field theories of nuclear matter

    International Nuclear Information System (INIS)

    Friman, B.L.; Henning, P.A.

    1988-01-01

    We investigate the stability of the nuclear matter ground state with respect to small perturbations of the meson fields in relativistic mean-field theories. The popular σ-ω model is shown to have an instability at about twice the nuclear density, which gives rise to a new ground state with periodic spin alignment. Taking into account the contributions of the Dirac sea properly, this instability vanishes. Consequences for relativistic heavy-ion collisions are discussed briefly. (orig.)

  4. French effort in field NDT nuclear plant

    International Nuclear Information System (INIS)

    Saglio, R.

    1983-12-01

    For the in-service inspection of nuclear generating stations, the French Atomic Commission has built up a program first to increase the defect detection probability, secondly to increase the reliability and recently to improve the characterization of defects. Focused Ultrasound and multiple frequency eddy current techniques, developped by French Atomic Energy Commission are well known. In this paper we will present the latest developments made in relation with defect characterization

  5. Linear accelerator use in the nuclear field

    International Nuclear Information System (INIS)

    Lecomte, J.-C.

    Radiography of internal conformity is performed on weldments and thick castings using linear accelerators. The basic principles relating to linear accelerators are outlined and their advantages over Co 60 sources described. Linear accelerator operation related requirements are presented as well as the use of this apparatus as a method for volumetric inspection, during fabrication of French Nuclear Steam Supply Systems (NSSS). Finally the resources needed to use this technique as an inspection method is dealt with [fr

  6. Isospin-dependent properties of asymmetric nuclear matter in relativistic mean field models

    Science.gov (United States)

    Chen, Lie-Wen; Ko, Che Ming; Li, Bao-An

    2007-11-01

    Using various relativistic mean-field models, including nonlinear ones with meson field self-interactions, models with density-dependent meson-nucleon couplings, and point-coupling models without meson fields, we have studied the isospin-dependent bulk and single-particle properties of asymmetric nuclear matter. In particular, we have determined the density dependence of nuclear symmetry energy from these different relativistic mean-field models and compared the results with the constraints recently extracted from analyses of experimental data on isospin diffusion and isotopic scaling in intermediate energy heavy-ion collisions as well as from measured isotopic dependence of the giant monopole resonances in even-A Sn isotopes. Among the 23 parameter sets in the relativistic mean-field model that are commonly used for nuclear structure studies, only a few are found to give symmetry energies that are consistent with the empirical constraints. We have also studied the nuclear symmetry potential and the isospin splitting of the nucleon effective mass in isospin asymmetric nuclear matter. We find that both the momentum dependence of the nuclear symmetry potential at fixed baryon density and the isospin splitting of the nucleon effective mass in neutron-rich nuclear matter depend not only on the nuclear interactions but also on the definition of the nucleon optical potential.

  7. Pairing gaps from nuclear mean-field models

    International Nuclear Information System (INIS)

    Bender, M.; Rutz, K.; Maruhn, J.A.

    2000-01-01

    We discuss the pairing gap, a measure for nuclear pairing correlations, in chains of spherical, semi-magic nuclei in the framework of self-consistent nuclear mean-field models. The equations for the conventional BCS model and the approximate projection-before-variation Lipkin-Nogami method are formulated in terms of local density functionals for the effective interaction. We calculate the Lipkin-Nogami corrections of both the mean-field energy and the pairing energy. Various definitions of the pairing gap are discussed as three-point, four-point and five-point mass-difference formulae, averaged matrix elements of the pairing potential, and single-quasiparticle energies. Experimental values for the pairing gap are compared with calculations employing both a delta pairing force and a density-dependent delta interaction in the BCS and Lipkin-Nogami model. Odd-mass nuclei are calculated in the spherical blocking approximation which neglects part of the the core polarization in the odd nucleus. We find that the five-point mass difference formula gives a very robust description of the odd-even staggering, other approximations for the gap may differ from that up to 30% for certain nuclei. (orig.)

  8. Mean field approach to nuclear structure

    International Nuclear Information System (INIS)

    Nazarewicz, W.; Tennessee Univ., Knoxville, TN

    1993-01-01

    Several examples of mean-field calculations, relevant to the recent and planned low-spin experimental works, are presented. The perspectives for future studies (mainly related to spectroscopy of exotic nuclei) are reviewd

  9. Parahydrogen-enhanced zero-field nuclear magnetic resonance

    Science.gov (United States)

    Theis, T.; Ganssle, P.; Kervern, G.; Knappe, S.; Kitching, J.; Ledbetter, M. P.; Budker, D.; Pines, A.

    2011-07-01

    Nuclear magnetic resonance, conventionally detected in magnetic fields of several tesla, is a powerful analytical tool for the determination of molecular identity, structure and function. With the advent of prepolarization methods and detection schemes using atomic magnetometers or superconducting quantum interference devices, interest in NMR in fields comparable to the Earth's magnetic field and below (down to zero field) has been revived. Despite the use of superconducting quantum interference devices or atomic magnetometers, low-field NMR typically suffers from low sensitivity compared with conventional high-field NMR. Here we demonstrate direct detection of zero-field NMR signals generated through parahydrogen-induced polarization, enabling high-resolution NMR without the use of any magnets. The sensitivity is sufficient to observe spectra exhibiting 13C-1H scalar nuclear spin-spin couplings (known as J couplings) in compounds with 13C in natural abundance, without the need for signal averaging. The resulting spectra show distinct features that aid chemical fingerprinting.

  10. Effects of retarded electrical fields on observables sensitive to the high-density behavior of the nuclear symmetry energy in heavy-ion collisions at intermediate energies

    Science.gov (United States)

    Wei, Gao-Feng; Li, Bao-An; Yong, Gao-Chan; Ou, Li; Cao, Xin-Wei; Liu, Xu-Yang

    2018-03-01

    Within the isospin- and momentum-dependent transport model IBUU11, we examine the relativistic retardation effects of electrical fields on the π-/π+ ratio and neutron-proton differential transverse flow in heavy-ion collisions at intermediate energies. Compared to the static Coulomb fields, the retarded electric fields of fast-moving charges are known to be anisotropic and the associated relativistic corrections can be significant. They are found to increase the number of energetic protons in the participant region at the maximum compression by as much as 25% but that of energetic neutrons by less than 10% in 197Au+197Au reactions at a beam energy of 400 MeV/nucleon. Consequently, more π+ and relatively fewer π- mesons are produced, leading to an appreciable reduction of the π-/π+ ratio compared to calculations with the static Coulomb fields. Also, the neutron-proton differential transverse flow, as another sensitive probe of high-density symmetry energy, is also decreased appreciably due to the stronger retarded electrical fields in directions perpendicular to the velocities of fast-moving charges compared to calculations using the isotropic static electrical fields. Moreover, the retardation effects on these observables are found to be approximately independent of the reaction impact parameter.

  11. Predominance and Role of Myanmar Women in Nuclear Related Fields

    International Nuclear Information System (INIS)

    Nyein, T.N.; Tharn Diang, A.

    2015-01-01

    This poster reflects the current and future endeavor of Myanmar women in nuclear science and technology related fields. Though Myanmar has not yet planned for nuclear power program, but strongly interested in nuclear energy due to rising awareness of future energy demand. The DAE is central in conducting career development, (E&T) as well as (R&D) in nuclear application fields, cooperating with the international societies and local institutions. According to survey, the status of women power in administration, rule and regulation sector is 62%, that in research, 34%, that in radiation application and protection, 57% and that in education and training, 46%. The current trend indicates that female are perceptibly wider participants in DAE. Qualified personnel and sufficient human resource are of essence in nuclear engineering and science. Thus, so as not to face the shortage of personnel, we aim to promote the interest of young generation ,to make competent and efficient manpower based on current and future national nuclear programmes since the parliament agreed on decision for acceleration of human resource development in nuclear field in order to urge government on June 23, 2014. Moreover, activities should be undertaken by the government and associated departments to persuade the interest of secondary and high school level student, to enhance academic programme for nuclear engineering and other sciences in private and government technical schools and training centre, to develop infrastructure according to near future nuclear programs, to enlighten people the benefits of nuclear science and technology and applications, and to raise public awareness of zero carbon emitting energy resource. These potential efforts should be extended, upgraded and encouraged not only by government, stakeholders and also by the help of nuclear network of other international organizations, since larger numbers of WiN Myanmar are required to access practically and globally integrated

  12. Safety culture in the nuclear field

    International Nuclear Information System (INIS)

    2005-09-01

    The council of IAEA governors ratified twelve elemental principles of physical protection of nuclear matters and installations. These principles will be included in the future updating of the international convention on the physical protection. The F basic principle proposes a definition of the safety culture and recommends that its implementation and its perenniality to be a reality in the concerned organisms.It appears as necessary to precise the concept of safety culture. The twelve principles are as follow: A State liability, B liability during international transports, C legislative and regulatory framework, D competent authority, E operators liability, F safety culture, G threats, H graduated approach, I deep defence, J assurance of the quality, K emergency plan, L confidentiality. The present document is complementary of INSAG-4, 1991 (safety series number 75, INSAG-4 safety culture, a report by the international nuclear safety advisory group, IAEA, 1991) that presents a concept of safety culture. It proposes also, in a particular chapter, the comparisons( common points and specificities) between safety culture and security culture. (N.C.)

  13. Nuclear effects hardened shelters

    International Nuclear Information System (INIS)

    Lindke, P.

    1990-01-01

    This paper reports on the Houston Fearless 76 Government Projects Group that has been actively engaged for more than twenty-five years as a sub-contractor and currently as a prime contractor in the design, manufacture, repair and logistics support of custom mobile ground stations and their equipment accommodations. Other associated products include environmental control units (ECU's), mobilizers for shelters and a variety of mobile power generation units (MPU's). Since 1984, Houston Fearless 76 has designed and manufactured four 8 foot by 8 foot x 22 foot nuclear hardened mobile shelters. These shelters were designed to contain electronic data processing/reduction equipment. One shelter is currently being operated by the Air Force as a Defense Intelligence Agency (DIA) approved and certified Special Compartmented Information Facility (SCIF). During the development and manufacturing process of the shelters, we received continual technical assistance and design concept evaluations from Science Applications International Corporation (SAIC) Operations Analysis and Logistics Engineering Division and the Nondestructive Inspection Lab at McClellan AFB. SAIC was originally employed by the Air Force to design the nuclear hardening specifications applied to these shelters

  14. Quark effects in nuclear structure

    International Nuclear Information System (INIS)

    Watt, A.

    1987-01-01

    Some experimental data in nuclear structure physics cannot be explained on the assumption that nuclei consist of inert protons and neutrons. The quark model attributes a definite internal structure to nucleons and implies that their properties should change when embedded in a nucleus. This article reviews some of the experimental evidence for these effects and discusses some new aspects of nuclear structure predicted by the quark model

  15. In-plane nuclear field formation investigated in single self-assembled quantum dots

    Science.gov (United States)

    Yamamoto, S.; Matsusaki, R.; Kaji, R.; Adachi, S.

    2018-02-01

    We studied the formation mechanism of the in-plane nuclear field in single self-assembled In0.75Al0.25As /Al0.3Ga0.7As quantum dots. The Hanle curves with an anomalously large width and hysteretic behavior at the critical transverse magnetic field were observed in many single quantum dots grown in the same sample. In order to explain the anomalies in the Hanle curve indicating the formation of a large nuclear field perpendicular to the photo-injected electron spin polarization, we propose a new model based on the current phenomenological model for dynamic nuclear spin polarization. The model includes the effects of the nuclear quadrupole interaction and the sign inversion between in-plane and out-of-plane components of nuclear g factors, and the model calculations reproduce successfully the characteristics of the observed anomalies in the Hanle curves.

  16. Nuclear reorientation in static and radio-frequency electro-magnetic fields

    International Nuclear Information System (INIS)

    Dubbers, D.

    1976-01-01

    Nuclear reorientation by external electromagnetic fields is treated using Fano's irreducible tensor formulation of the problem. Although the main purpose of this paper is the description of the effects of nuclear magnetic resonance (NMR) on an ensemble of oriented nuclei in the presence of a crystal electric field gradient (efg), the results are applicable to all types of nuclear or atomic orientation or angular correlation work. The theory is applied to a number of exemplary cases: magnetic field dependence of nuclear orientation in the presence of quadrupole interactions; sign determination in electric quadrupole coupling; line shapes of nuclear acoustic resonance (NAR) signals; quadrupole splitting and multiquantum transitions in NMR with oriented nuclei. (orig./WBU) [de

  17. Development and applications of NMR [nuclear magnetic resonance] in low fields and zero field

    International Nuclear Information System (INIS)

    Bielecki, A.

    1987-05-01

    This dissertation is about nuclear magnetic resonance (NMR) spectroscopy in the absence of applied magnetic fields. NMR is usually done in large magnetic fields, often as large as can be practically attained. The motivation for going the opposite way, toward zero field, is that for certain types of materials, particularly powdered or polycrystalline solids, the NMR spectra in zero field are easier to interpret than those obtained in high field. 92 refs., 60 figs., 1 tab

  18. ¹³⁷Cs in irrigation water and its effect on paddy fields in Japan after the Fukushima nuclear accident.

    Science.gov (United States)

    Yoshikawa, Natsuki; Obara, Hitomi; Ogasa, Marie; Miyazu, Susumu; Harada, Naoki; Nonaka, Masanori

    2014-05-15

    There is concern that radiocesium deposited in the environment after the accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) in March 2011 will migrate to paddy fields through hydrological pathways and cause serious and long-lasting damage to the agricultural activities. This study was conducted in the Towa region of Nihonmatsu in the northern part of Fukushima Prefecture, Japan, (1) to quantify (137)Cs in stream water used to irrigate paddy fields by separating the dissolved and particulate components in water samples and then fractionating the particulate components bonded in different ways using a sequential extraction procedure, and (2) to determine the amounts of radiocesium newly added to paddy fields in irrigation water relative to the amounts of radiocesium already present in the fields from the deposition of atmospheric fallout immediately after the FDNPP accident. Three catchments were studied, and the (137)Cs activity concentrations in stream water samples were 79-198 mBq L(-1) under stable runoff conditions and 702-13,400 Bq L(-1) under storm runoff conditions. The residual fraction (F4, considered to be non-bioavailable) was dominant, accounting for 59.5-82.6% of the total (137)Cs activity under stable runoff conditions and 69.4-95.1% under storm runoff conditions. The (137)Cs newly added to paddy fields in irrigation water only contributed 0.03-0.05% of the amount already present in the soil (201-348 kBq m(-2)). This indicates that the (137)Cs inflow load in irrigation water is negligible compared with that already in the soil. However, the contribution from the potentially bioavailable fractions (F1+F2+F3) was one order of magnitude larger, accounting for 0.20-0.59%. The increase in the dissolved and soluble radiocesium fraction (F1) was especially large (3.0% to infinity), suggesting that radiocesium migration in irrigation water is increasing the accumulation of radiocesium in rice. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. French research in the field of nuclear agronomy

    International Nuclear Information System (INIS)

    Guerin De Montgareuil, P.

    1964-01-01

    This report presents a survey of the most important work in the field of nuclear agronomy carried out in France since the second international conference, ranging from pure research to the most direct application. As the programmes develop, so to an ever decreasing degree does this differentiation cover the distinction made in the report between the biological radiations effects and the other uses of nuclear techniques. Thus research on agricultural radio-genetics is carried on in two directions: from the theoretical and methodological angle, with comparative studies of the action of various types of radiation, the influence of dose rate and temperature, the action of chemical mutation agents, the production of chimera by gamma irradiation; and on the practical side, leading to the creation of new, hardier or earlier varieties (rice, millet, ground-nuts). Problems of pest destruction (eradication) and the preservation of foodstuffs by irradiation are also tackled by widely varied means and for totally different purposes. One operation consisting of a simple irradiation (moist seeds, potatoes...) will sometimes be associated with original studies of a biochemical or microbiological nature (for example: decomposition of starch, glucide metabolism of irradiated tubers, radiation resistance of yeasts). The nuclear technique side is represented mainly by radioisotopes (carbon 14, phosphorus 32, sulphur 35, calcium 45, potassium 42, copper 64, gold 198) and stable isotopes analysed by mass spectrometer (nitrogen 15, oxygen 18) or by neutron activation (boron 10). The studies mentioned refer to problems on different levels concerning plant physiology, agrology, agricultural entomology and zootechny. Results obtained from measurements of the humidity (neutron thermalization) and density (gamma diffusion) of a soil are also given. Numerous organisations take part in these various research programmes, each according to its speciality: cooperative private enterprise

  20. The Effects of Nuclear Weapons

    Energy Technology Data Exchange (ETDEWEB)

    Glasstone, Samuel

    1964-02-01

    This book is a revision of "The Effects of Nuclear Weapons" which was issued in 1957. It was prepared by the Defense Atomic Support Agency of the Department of Defense in coordination with other cognizant governmental agencies and was published by the U.S. Atomc Energy Commission. Although the complex nature of nuclear weapons effects does not always allow exact evaluation, the conclusions reached herein represent the combined judgment of a number of the most competent scientists working the problem. There is a need for widespread public understanding of the best information available on the effects of nuclear weapons. The purpose of this book is to present as accurately as possible, within the limits of national security, a comprehensive summary of this information.

  1. Quark effects in nuclear physics

    International Nuclear Information System (INIS)

    Miller, G.A.

    1983-01-01

    A phenomenological approach which enables the size of quark effects in various nuclear processes is discussed. The principle of conservation of probability provides significant constraints on six quark wave functions. Using this approach, it is found that the low-energy proton-proton weak interaction can be explained in terms of W and Z boson exchanges between quarks. That the value of the asymptotic ratio of D to S state wave functions is influenced (at the 5% level) by quark effects, is another result of our approach. We have not discovered a nuclear effect that can be uniquely explained by quark-quark interactions. However it does seem that quark physics is very relevant for nuclear physics. 52 references

  2. Title list of selected Soviet reports in the fields of nuclear research and nuclear engineering. 9

    International Nuclear Information System (INIS)

    Schumann, G.; Sube, R.

    1979-03-01

    140 titles of reports issued by Soviet institutes (KFTI, EFI, IAE, IFVE, ITEF, NIIAR, NIIEFA, FEI, RI, SFTI) in the fields of nuclear research and nuclear engineering have been arranged according to the INIS subject scope. The reports are available on a loan basis from ZfK Rossendorf, Information Department, Dresden

  3. Title list of selected Soviet reports in the fields of nuclear research and nuclear engineering. 7

    International Nuclear Information System (INIS)

    Schumann, G.; Sube, R.

    1979-03-01

    139 titles of reports issued by Soviet institutes (KFTI, EFI, IAE, IFVE, ITEF, NIIAR, NIIEFA, FEI, RI, SFTI) in the fields of nuclear research and nuclear engineering have been arranged according to the INIS subject scope. The reports are available on a loan basis from ZfK Rossendorf, Information Department, Dresden

  4. Title list of selected Soviet reports in the fields of nuclear research and nuclear engineering. 13

    International Nuclear Information System (INIS)

    Schumann, G.; Sube, R.

    1979-12-01

    136 titles of reports issued by Soviet institutes (KFTI, EFI, IAE, IFVE, ITEF, NIIAR, NIIEFA, FEI, RI, SFTI) in the fields of nuclear research and nuclear engineering have been arranged according to the INIS subject scope. The reports are available on a loan basis from ZfK Rossendorf, Information Department, Dresden

  5. The supervisions in the field develop nuclear professionals; Las supervisiones en campo desarrollan profesionales nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez de la Casa, M.; Buedo, J. L.; Gonzalez, F.

    2015-07-01

    In 2011 Cofrentes Nuclear Power Plants began a training program for improving the supervision of managers in the field: the effort done not only has improved the quality of supervisions but also has defined a way to reinforce behavior expectations of Cofrentes Nuclear Power Plant. (Author)

  6. Title list of selected Soviet reports in the fields of nuclear research and nuclear engineering. 14

    International Nuclear Information System (INIS)

    Schumann, G.; Sube, R.

    1979-12-01

    136 titles of reports issued by Soviet institutes (KFTI, EFI, IAE, IFVE, ITEF, NIIAR, NIIEFA, FEI, RI, SFTI) in the fields of nuclear research and nuclear engineering have been arranged according to the INIS subject scope. The reports are available on a loan basis from ZfK Rossendorf, Information Department, Dresden

  7. Title list of selected Soviet reports in the fields of nuclear research and nuclear engineering. 11

    International Nuclear Information System (INIS)

    Schumann, G.; Sube, R.

    1979-07-01

    158 titles of reports issued by Soviet institutes (KFTI, EFI, IAE, IFVE, ITEF, NIIAR, NIIEFA, FEI, RI, SFTI) in the fields of nuclear research and nuclear engineering have been arranged according to the INIS subject scope. The reports are available on a loan basis from ZfK Rossendorf, Information Department, Dresden

  8. Title list of selected Soviet reports in the fields of nuclear research and nuclear engineering. 6

    International Nuclear Information System (INIS)

    Schumann, G.; Sube, R.

    1979-03-01

    135 titles of reports issued by Soviet institutes (KFTI, EFI, IAE, IFVE, ITEF, NIIAR, NIIEFA, FEI, RI, SFTI) in the fields of nuclear research and nuclear engineering have been arranged according to the INIS subject scope. The reports are available on a loan basis from ZfK Rossendorf, Information Department, Dresden

  9. Title list of selected Soviet reports in the fields of nuclear research and nuclear engineering. 5

    International Nuclear Information System (INIS)

    Schumann, G.; Sube, R.

    1979-03-01

    133 titles of reports issued by Soviet institutes (KFTI, EFI, IAE, IFVE, ITEF, NIIAR, NIIEFA, FEI, RI, SFTI) in the fields of nuclear research and nuclear engineering have been arranged according to the INIS subject scope. The reports are available on a loan basis from ZfK Rossendorf, Information Department, Dresden

  10. Title list of selected Soviet reports in the fields of nuclear research and nuclear engineering. 12

    International Nuclear Information System (INIS)

    Schumann, G.; Sube, R.

    1979-12-01

    136 titles of reports issued by Soviet institutes (KFTI, EFI, IAE, IFVE, ITEF, NIIAR, NIIEFA, FEI, RI, SFTI) in the fields of nuclear research and nuclear engineering have been arranged according to the INIS subject scope. The reports are available on a loan basis from ZfK Rossendorf, Information Department, Dresden

  11. Title list of selected Soviet reports in the fields of nuclear research and nuclear engineering. 8

    International Nuclear Information System (INIS)

    Schumann, G.; Sube, R.

    1979-03-01

    141 titles of reports issued by Soviet institutes (KFTI, EFI, IAE, IFVE, ITEF, NIIAR, NIIEFA, FEI, RI, SFTI) in the fields of nuclear research and nuclear engineering have been arranged according to the INIS subject scope. The reports are available on a loan basis from ZfK Rossendorf, Information Department, Dresden

  12. Title list of selected Soviet reports in the fields of nuclear research and nuclear engineering. 4

    International Nuclear Information System (INIS)

    Schumann, G.; Sube, R.

    1979-03-01

    135 titles of reports issued by Soviet institutes (KFTI, EFI, IAE, IFVE, ITEF, NIIAR, NIIEFA, FEI, RI, SFTI) in the fields of nuclear research and nuclear engineering have been arranged according to the INIS subject scope. The reports are available on a loan basis from ZfK Rossendorf, Information Department, Dresden

  13. Title list of selected Soviet reports in the fields of nuclear research and nuclear engineering. 15

    International Nuclear Information System (INIS)

    Schumann, G.; Sube, R.

    1979-12-01

    137 titles of reports issued by Soviet institutes (KFTI, EFI, IAE, IFVE, ITEF, NIIAR, NIIEFA, FEI, RI, SFTI) in the fields of nuclear research and nuclear engineering have been arranged according to the INIS subject scope. The reports are available on a loan basis from ZfK Rossendorf, Information Department, Dresden

  14. Title list of selected Soviet reports in the fields of nuclear research and nuclear engineering. 10

    International Nuclear Information System (INIS)

    Schumann, G.; Sube, R.

    1979-07-01

    142 titles of reports issued by Soviet institutes (KFTI, EFI, IAE, IFVE, ITEF, NIIAR, NIIEFA, FEI, RI, SFTI) in the fields of nuclear research and nuclear engineering have been arranged according to the INIS subject scope. The reports are available on a loan basis from ZfK Rossendorf, Information Department, Dresden

  15. Title list of selected Soviet reports in the fields of nuclear research and nuclear engineering. 0

    International Nuclear Information System (INIS)

    Schumann, G.; Sube, R.

    1977-09-01

    161 titles of reports issued by Soviet institutes (KFTI, EFI, IAE, IFVE, ITEF, NIIAR, NIIEFA, FEI, RI, SFTI) in the fields of nuclear research and nuclear engineering have been arranged according to the INIS subject scope. The reports are availabl on a loan basis from ZfK Rossendorf, Information Department, Dresden

  16. Velocity fields and transition densities in nuclear collective modes

    Energy Technology Data Exchange (ETDEWEB)

    Stringari, S [Dipartimento di Matematica e Fisica, Libera Universita di Trento, Italy

    1979-08-13

    The shape of the deformations occurring in nuclear collective modes is investigated by means of a microscopic approach. Analytical solutions of the equations of motion are obtained by using simplified nuclear potentials. It is found that the structure of the velocity field and of the transition density of low-lying modes is considerably different from the predictions of irrotational hydrodynamic models. The low-lying octupole state is studied in particular detail by using the Skyrme force.

  17. RPA correlations and nuclear densities in relativistic mean field approach

    International Nuclear Information System (INIS)

    Van Giai, N.; Liang, H.Z.; Meng, J.

    2007-02-01

    The relativistic mean field approach (RMF) is well known for describing accurately binding energies and nucleon distributions in atomic nuclei throughout the nuclear chart. The random phase approximation (RPA) built on top of the RMF is also a good framework for the study of nuclear excitations. Here, we examine the consequences of long range correlations brought about by the RPA on the neutron and proton densities as given by the RMF approach. (authors)

  18. Development of training courses in the field of nuclear energy

    International Nuclear Information System (INIS)

    Lee, Han Young; Seo, In Seok; Lee, Eui Jin; Seo, Kyung Won; Won, Jong Yeol; Nam, Jae Yeol

    1996-02-01

    This report describes the final results of D evelopment of training courses in the field of nuclear energy . The scope and contents are as follows : 1. to develop specialized nuclear training programs. 2. to collect and analyze foreign training programs and materials. 3. to develop foreign assisted training courses. 4. to develop interregional training courses for developing country trainees. and 5. to develop text materials for the implementation of training courses. 16 refs. (Author)

  19. Analysis of the Effect of Chronic and Low-Dose Radiation Exposure on Spermatogenic Cells of Male Large Japanese Field Mice ( Apodemus speciosus ) after the Fukushima Daiichi Nuclear Power Plant Accident.

    Science.gov (United States)

    Takino, Sachio; Yamashiro, Hideaki; Sugano, Yukou; Fujishima, Yohei; Nakata, Akifumi; Kasai, Kosuke; Hayashi, Gohei; Urushihara, Yusuke; Suzuki, Masatoshi; Shinoda, Hisashi; Miura, Tomisato; Fukumoto, Manabu

    2017-02-01

    In this study we analyzed the effect of chronic and low-dose-rate (LDR) radiation on spermatogenic cells of large Japanese field mice ( Apodemus speciosus ) after the Fukushima Daiichi Nuclear Power Plant (FNPP) accident. In March 2014, large Japanese field mice were collected from two sites located in, and one site adjacent to, the FNPP ex-evacuation zone: Tanashio, Murohara and Akogi, respectively. Testes from these animals were analyzed histologically. External dose rate from radiocesium (combined 134 Cs and 137 Cs) in these animals at the sampling sites exhibited 21 μGy/day in Tanashio, 304-365 μGy/day in Murohara and 407-447 μGy/day in Akogi. In the Akogi group, the numbers of spermatogenic cells and proliferating cell nuclear antigen (PCNA)-positive cells per seminiferous tubule were significantly higher compared to the Tanashio and Murohara groups, respectively. TUNEL-positive apoptotic cells tended to be detected at a lower level in the Murohara and Akogi groups compared to the Tanashio group. These results suggest that enhanced spermatogenesis occurred in large Japanese field mice living in and around the FNPP ex-evacuation zone. It remains to be elucidated whether this phenomenon, attributed to chronic exposure to LDR radiation, will benefit or adversely affect large Japanese field mice.

  20. The effective nuclear potential

    International Nuclear Information System (INIS)

    Skyrme, T.H.R.

    1994-01-01

    An empirical analyses is made of the mean effective internucleon potential required in the shell-model description of nuclei, allowing for the presence of many-body effects as suggested by current theory. A consistent description is found in which the effective two-body interaction acts almost entirely in even states, and the many-body effects are simulated by a repulsive three-body contact interaction. The strength of the two-body interaction is consistent with that expressed by the free scattering matrix of the two-nucleon system, and that of the three-body interaction with the 'rearrangement energy' calculated in the many-body theory. (author). 21 refs, 2 figs, 7 tabs

  1. Isotope effects on nuclear shielding

    International Nuclear Information System (INIS)

    Hansen, P.E.

    1983-01-01

    This review concentrates upon empirical trends and practical uses of mostly secondary isotope effects, both of the intrinsic and equilibrium types. The text and the tables are arranged in the following fashion. The most 'popular' isotope effect is treated first, deuterium isotope effects on 13 C nuclear shielding, followed by deuterium on 1 H nuclear shieldings, etc. Focus is thus on the isotopes producing the effect rather than on the nuclei suffering the effect. After a brief treatment of each type of isotope effect, general trends are dealt with. Basic trends of intrinsic isotope effects such as additivity, solvent effects, temperature effects, steric effects, substituent effects and hyperconjugation are discussed. Uses of isotope effects for assignment purposes, in stereochemical studies, in hydrogen bonding and in isotopic tracer studies are dealt with. Kinetic studies, especially of phosphates, are frequently performed by utilizing isotope effects. In addition, equilibrium isotope effects are treated in great detail as these are felt to be new and very important and may lead to new uses of isotope effects. Techniques used to obtain isotope effects are briefly surveyed at the end of the chapter. (author)

  2. The field treatment of the nuclear spectrum. Historical foundation and two contributions to its ensuing development

    International Nuclear Information System (INIS)

    Bes, Daniel R

    2016-01-01

    The highlights of the model which was developed during the 1950s at the Niels Bohr Institute, Copenhagen, under the leadership of Aage Bohr and Ben Mottelson, are described in this contribution. Subsequently, it is shown that the field concept—the fundamental tool of the unified model—is not only an intelligent guess to describe the difficult many-body nuclear system. By means of a systematic expansion of field-coupling effects, the nuclear field theory (NFT) accounts for the overcompleteness of the initial product basis and the overlooking of the Pauli principle acting between constituents of the basis. Eventually it leads to the exact solution of the nuclear many-body problem. The description in terms of fields involves another problem if the field violates a symmetry inherent to the initial problem. The solution is borrowed from the BRST treatments of gauge systems, in which the lost symmetry is replaced by a more powerful one. (invited comment)

  3. The relativistic mean-field description of nuclei and nuclear dynamics

    International Nuclear Information System (INIS)

    Reinhard, P.G.

    1989-01-01

    The relativistic mean-field model of the nucleus is reviewed. It describes the nucleus as a system of Dirac-Nucleons which interact in a relativistic covariant manner via meson fields. The meson fields are treated as mean fields, i.e. as non quantal c-number fields. The effects of the Dirac sea of the nucleons is neglected. The model is interpreted as a phenomenological ansatz providing a selfconsistent relativistic description of nuclei and nuclear dynamics. It is viewed, so to say, as the relativistic generalisation of the Skyrme-Hartree-Fock ansatz. The capability and the limitations of the model to describe nuclear properties are discussed. Recent applications to spherical and deformed nuclei and to nuclear dynamics are presented. (orig.)

  4. Effectiveness of Existing International Nuclear Liability Regime

    International Nuclear Information System (INIS)

    Al-Doais, Salwa; Kessel, Daivd

    2015-01-01

    The first convention was the Paris Convention on Third Party Liability in the Field of Nuclear Energy (the Paris Convention) had been adopted on 29 July 1960 under the auspices of the OECD, and entered into force on 1 April 1968. In 1963,the Brussels Convention - supplementary to the Paris Convention- was adopted in to provide additional funds to compensate damage as a result of a nuclear incident where Paris Convention funds proved to be insufficient. The IAEA's first convention was the Vienna Convention on Civil Liability for Nuclear Damage (the Vienna Convention) which adopted on 21 May 1963,and entered into force in 1977. Both the Paris Convention and the Vienna Convention laid down very similar nuclear liability rules based on the same general principles. The broad principles in these conventions can be summarized as follows: 1- The no-fault liability principle (strict liability) 2- Liability is channeled exclusively to the operator of the nuclear installation (legal channeling) 3- Only courts of the state in which the nuclear accident occurs would have jurisdiction (exclusive jurisdiction) 4- Limitation of the amount of liability and the time frame for claiming damages (limited liability) 5- The operator is required to have adequate insurance or financial guarantees to the extent of its liability amount (liability must be financially secured). 6- Liability is limited in time. Compensation rights are extinguished after specific time. 7- Non-discrimination of victims on the grounds of nationality, domicile or residence. Nuclear liability conventions objective is to provide adequate compensation payments to victims of a nuclear accident. Procedures for receiving these compensation are controlled by some rules such as exclusive jurisdiction, that rule need a further amendment to ensure the effectiveness of the exiting nuclear liability regime . Membership of the Conventions is a critical issue, because the existence of the conventions without being party to

  5. Effectiveness of Existing International Nuclear Liability Regime

    Energy Technology Data Exchange (ETDEWEB)

    Al-Doais, Salwa; Kessel, Daivd [KEPCO International Nuclear Graduate School, Daejeon (Korea, Republic of)

    2015-10-15

    The first convention was the Paris Convention on Third Party Liability in the Field of Nuclear Energy (the Paris Convention) had been adopted on 29 July 1960 under the auspices of the OECD, and entered into force on 1 April 1968. In 1963,the Brussels Convention - supplementary to the Paris Convention- was adopted in to provide additional funds to compensate damage as a result of a nuclear incident where Paris Convention funds proved to be insufficient. The IAEA's first convention was the Vienna Convention on Civil Liability for Nuclear Damage (the Vienna Convention) which adopted on 21 May 1963,and entered into force in 1977. Both the Paris Convention and the Vienna Convention laid down very similar nuclear liability rules based on the same general principles. The broad principles in these conventions can be summarized as follows: 1- The no-fault liability principle (strict liability) 2- Liability is channeled exclusively to the operator of the nuclear installation (legal channeling) 3- Only courts of the state in which the nuclear accident occurs would have jurisdiction (exclusive jurisdiction) 4- Limitation of the amount of liability and the time frame for claiming damages (limited liability) 5- The operator is required to have adequate insurance or financial guarantees to the extent of its liability amount (liability must be financially secured). 6- Liability is limited in time. Compensation rights are extinguished after specific time. 7- Non-discrimination of victims on the grounds of nationality, domicile or residence. Nuclear liability conventions objective is to provide adequate compensation payments to victims of a nuclear accident. Procedures for receiving these compensation are controlled by some rules such as exclusive jurisdiction, that rule need a further amendment to ensure the effectiveness of the exiting nuclear liability regime . Membership of the Conventions is a critical issue, because the existence of the conventions without being party to

  6. Foundation field bus in the Spanish nuclear sector

    International Nuclear Information System (INIS)

    Saez de Montagut Revenga, G.

    2013-01-01

    This paper deals with the modification made in power plants nuclear ASCO 1 and 2 in which scans is the level Control system of Heaters to implementing an Ovation system, as well as the standard Foundation Field bus for field communications. This digitalisation has required a detailed study of the implications on security that could have the centralization of control loops in main feedwater system.

  7. NMR magnetic field controller for pulsed nuclear magnetic resonance experiments

    International Nuclear Information System (INIS)

    Scheler, G.; Anacker, M.

    1975-01-01

    A nuclear magnetic resonance controller for magnetic fields, which can also be used for pulsed NMR investigations, is described. A longtime stability of 10 -7 is achieved. The control signal is generated by a modified time sharing circuit with resonance at the first side band of the 2 H signal. An exact calibration of the magnetic field is achieved by the variation of the H 1 - or of the time-sharing frequency. (author)

  8. Relation between Romanian NGOs Acting in Nuclear Field and Other Stakeholders

    International Nuclear Information System (INIS)

    Andrei, V.; Pantazi, D.; Radulescu, G.; Bucur, C.; Stanciu, L.; Apostol Minodora, M.

    2015-01-01

    In Romania, three main NGOs act in promoting peaceful use of nuclear energy. The organization with the longest road is the Romanian Association for Nuclear Energy (AREN), created by individual persons acting in nuclear field in 1990. In 2001, a number of Romanian and foreign legal entities having core competence or unfolding nuclear energy related industrial and research activities created the Romanian Industrial Forum (Romatom). Both AREN and Romatom are active parts of European nuclear world: AREN is European Nuclear Society member and Romatom is Foratom member. The 3rd NGO is Women in Nuclear Romania (WiNRo) which registered in 2011. However, the women acting in nuclear field have become earlier active independent voices particularly in public communication on nuclear field matters. The debut was in 1993 when the women group acting in AREN became members of WiN Global, the organization that they trust would become a real opportunity to share their professional competences and improve their communication knowledge and skills in the light of the mission they decided to embrace, namely, that of clear, transparent and trustful communication with stakeholders, particularly the general public on peaceful use of nuclear energy. Today, WiN Ro is also part of WiN Europe where common European desiderates aim to establish and achieve. Today, Romanian NGOs act to continue the trustful relations they have built with a large portfolio of stakeholders adapting their endeavors for answering to various stakeholders needs for transparency and effective communication on nuclear matters at national level. At international level, the Romanian NGOs aim to register benefic experience for their organizational works and opportunities for promotion of the national good approaches, from relations with stakeholders acting in the international arena of nuclear world. Relevant aspects on how the Romanian NGOs have approached relations with stakeholders will be presented. (author)

  9. Climatic effects of nuclear war

    International Nuclear Information System (INIS)

    Covey, C.

    1985-01-01

    Global climatic consequences of a nuclear war have, until recently, been assumed to be insignificant compared with the obviously devastating direct effects from blast, heat, and short-term fallout. But a number of investigations carried out over the past few years indicate that climatic impact could actually be severe enough to threaten the global ecosystem significantly, including regions that may not have been directly involved in the war. This change in perception comes as researchers realize that the fires ignited by nuclear explosions would generate so much smoke that, even spread over a large portion of Earth's surface, densities could be high enough to block most of the sunlight normally reaching the ground. As a result, temperatures could decrease below freezing in a nuclear winter lasting weeks to months. Smoke from fires is what would make nuclear winter so severe. Of necessity, theoretical models are relied upon to estimate the climatic impact of nuclear war. The models incorporate many uncertain assumptions, particularly regarding the small-scale details of smoke production by fires

  10. The imitator of nuclear explosion signals for field operations

    International Nuclear Information System (INIS)

    Wang Lusong; Xie Yujun; Tan Youjin; Wang Liping

    1999-01-01

    According to the present system of the nuclear explosion monitoring equipment (NEME), the imitator of nuclear explosion signals for field operation is urgently needed by NEME, which has been fitted out to the army and some new types that will be finalized soon. The authors have made the imitator for the equipment, and as the cause of this research, it can be used not only in training and maintenance for army but also in research and production for scientific research institutions and industrial enterprise. Function of this imitator is to imitate the NEMP, the light and shock wave signals of nuclear explosion in proper order. The time difference of the process accords with the true location of nuclear explosion. This research is of great military importance

  11. The Effects of Nuclear Weapons

    Science.gov (United States)

    1977-01-01

    34Nuclear Explosion Effects Practice No. 42, 1961. on Structui’es and Protective Construction-A * ARMOUR RESEARCH FOUNDATION, "A Sim- Selected Bibliography...34 U.S. Atomic Energy p1e Method of Evaluating Blast Effects on Commission, April 1961, TID-3092. Buildihigs," Armour Research Foundation, PI(KERINU, E...stripes have been destroyed by the heat fiom the therm. al radiation. lion points could receive thermal radia- as shades, curtains, and drapes . Of

  12. Imaging using long range dipolar field effects

    International Nuclear Information System (INIS)

    Gutteridge, Sarah

    2002-01-01

    The work in this thesis has been undertaken by the author, except where indicated in reference, within the Magnetic Resonance Centre, at the University of Nottingham during the period from October 1998 to March 2001. This thesis details the different characteristics of the long range dipolar field and its application to magnetic resonance imaging. The long range dipolar field is usually neglected in nuclear magnetic resonance experiments, as molecular tumbling decouples its effect at short distances. However, in highly polarised samples residual long range components have a significant effect on the evolution of the magnetisation, giving rise to multiple spin echoes and unexpected quantum coherences. Three applications utilising these dipolar field effects are documented in this thesis. The first demonstrates the spatial sensitivity of the signal generated via dipolar field effects in structured liquid state samples. The second utilises the signal produced by the dipolar field to create proton spin density maps. These maps directly yield an absolute value for the water content of the sample that is unaffected by relaxation and any RF inhomogeneity or calibration errors in the radio frequency pulses applied. It has also been suggested that the signal generated by dipolar field effects may provide novel contrast in functional magnetic resonance imaging. In the third application, the effects of microscopic susceptibility variation on the signal are studied and the relaxation rate of the signal is compared to that of a conventional spin echo. (author)

  13. Contribution to the Brazilian legislation in nuclear energy field

    International Nuclear Information System (INIS)

    Barbosa, Jose Alberto Maia

    2009-01-01

    Nuclear technology: to keep its domain is actually considered a differential for a country in relation to other ones, being able to represent an international threat to be contained or an aspect on technological and political valorization for those ones with recognized international credibility. Face to a raising use of new technologies in the field and the requirement asking for regulation in accordance with international safety standards, in order to assure its employment, the objective of this study was to demonstrate whether occupational and environmental radioprotection performed in our country is within radiological and nuclear safety international standards, and so it was updated and revised the Brazilian law in nuclear energy area, by comparing it with European Union, contextualized strong and weak points from national law, indicating criticisms and suggestions, in order that modifications will be able to be accomplished, aiming to its adequacy to international standards. The considered hypothesis showed that are required changes in the regulation structure in Brazilian nuclear area, aiming to the creation of a regulator agency of nuclear activities, with the purpose of assuring that the state of art and of technology, in terms of nuclear safety, to be the basis of the exercise related to their normative, control and safety assessment activities, on environment preservation, public and workers health, face to nuclear energy applications. (author)

  14. Country report on human resource development in nuclear field

    International Nuclear Information System (INIS)

    Wanitsuksombut, Warapon; Noochpramool, Kovit

    2000-01-01

    The short-term plan is to promote utilization of the new research reactor in Thailand. The long-term plan is to gain public understanding and acceptance of nuclear technology. Since 1991, the office has conducted training and seminars in nuclear related field. The major training is in radiation protection, and training in nuclear reactor was at noticeably smaller portion. For ten years of training, 3,649 persons passed different radiation protection courses. Education programs in universities are outlined with the curriculums in the paper. It is clear that the manpower produced in nuclear field in Thailand is inadequate. Further more, most of them are working in limited areas in specific institutes, research laboratories, modern hospitals, and academic teaching. They seldom contact with the public. Hence communication to the public is lacking. After the training course for schoolteachers in our research reactor site, many of them appreciate new knowledge of nuclear technology. They became to realize that they had been involved with the nuclear technology before in their everyday well being. The urgent need is to arrange various suitable courses on research reactor utilization. In this effort, the exchange of information, equipment as well as teaching materials form developed institutes are necessary. The urgent need is a system of qualification for Radiation Protection Officer. By exchange of information and seminars, it may help the country to decide whether the harmonization and accreditation of training courses or the accredited examination is adopted. For long-term achievement, a regular seminar for schoolteacher should be formulated, and a program for social and economics curriculum in nuclear field should be initiated. (Tanaka, Y.)

  15. Couplex1 test case nuclear - Waste disposal far field simulation

    International Nuclear Information System (INIS)

    2001-01-01

    This first COUPLEX test case is to compute a simplified Far Field model used in nuclear waste management simulation. From the mathematical point of view the problem is of convection diffusion type but the parameters are highly varying from one layer to another. Another particularity is the very concentrated nature of the source, both in space and in time. (author)

  16. Ensuring the expert resources and education in nuclear energy field

    International Nuclear Information System (INIS)

    Pirilae, P.

    1987-01-01

    The Finnish Atomic Energy Commission has published a report ''The Situation and the Needs for Development of Education in the Nuclear Energy Field''. According to it, the needs concerning the volume of education are small and no problem for Finland. But, the problem is how to maintain the present high level of training and education within this small volume

  17. Development of cyber training system for nuclear fields

    International Nuclear Information System (INIS)

    Kim, Young Taek; Park, Jong Kyun; Lee, Eui Jin; Lee, Han Young; Choi, Nan Young

    2002-02-01

    This report describes on technical contents related cyber training system construct on KAERI Nuclear Training Center, and on using cases of cyber education in domestic and foreign countries. Also realtime training system through the internet and cyber training management system for atomic fields is developed. All users including trainee, course managers and lecturers can use new technical for create new paradigm

  18. Development of indigenous technology at CNEN in the fields of nuclear medicine, nuclear detectors, instrumentation, radioisotope production and application of nuclear techniques

    International Nuclear Information System (INIS)

    Mafra, O.

    1990-01-01

    The main objectives of the program developed at CNEN in the field of nuclear medicine, nuclear detectors, instrumentation, radioisotope production and application of nuclear technique are described. (E.G.) [pt

  19. Numerical simulation of interior flow field of nuclear model pump

    International Nuclear Information System (INIS)

    Wang Chunlin; Peng Na; Kang Can; Zhao Baitong; Zhang Hao

    2009-01-01

    Reynolds time-averaged N-S equations and the standard k-ε turbulent model were adopted, and three-dimensional non-structural of tetrahedral mesh division was used for modeling. Multiple reference frame model of rotating fluid mechanical model was used, under the design condition, the three-dimensional incompressible turbulent flow of nuclear model pump was simulated, and the results preferably post the characteristics of the interior flow field. This paper first analyzes the total pressure and velocity distribution in the flow field, and then describes the interior flow field characteristics of each part such as the impeller, diffuser and spherical shell, and also discusses the reasons that cause these characteristics. The study results can be used to estimate the performance of nuclear model pump, and will provide some useful references for its hydraulic optimized design. (authors)

  20. Nuclear energy: biological effects and environmental impact

    International Nuclear Information System (INIS)

    Boonefaes, M.

    1987-01-01

    This thesis is concerned with the large development of nuclear power plants and the recent nuclear catastrophe which has made clear how the hazards resulting from radioactivity affect public health and the environment. Environmental effects of nuclear power plants operating in normal conditions are small, but to obtain nuclear power plants of reduced radioactivity, optimization of their design, construction, operation and waste processing plays a decisive role. Biological effects of ionizing radiations and environmental impacts of Nuclear Power plants are developed [fr

  1. External magnetic field induced anomalies of spin nuclear dynamics in thin antiferromagnetic films

    International Nuclear Information System (INIS)

    Tarasenko, S.V.

    1995-01-01

    It is shown that if the thickness of homogeneously magnetized plate of high-axial antiferromagnetic within H external magnetic field becomes lower the critical one, then the effect of dynamic magnetoelastic interaction on Soul-Nakamura exchange of nuclear spins results in formation of qualitatively new types of spreading nuclear spin waves no else compared neither within the model of unrestricted magnetic nor at H = 0 in case of thin plate of high-axial antiferromagnetic. 10 refs

  2. Activities in the field of small nuclear power reactors

    Energy Technology Data Exchange (ETDEWEB)

    Baranaev, Yu.D.; Dolgov, V.V.; Sergeev, Yu.A. [Physics and Power Eng. Inst., Obninsk (Russian Federation). State Res. Centre

    1997-10-01

    Considerable efforts have been undertaken for development, design, construction and operation of small nuclear power plants (SNPP) in Russia. Systematic work in this area was started in the mid-1950s. The driving force for this activity was the awareness that the use of nuclear fuel would practically solve the problem of fuel transportation. As far as the remote northern regions are concerned, this provides the key advantage of nuclear over conventional energy sources. The activity in the field of SNPP has included pre-design analytical feasibility studies and experimental research including large-scale experiments on critical assemblies, thermal and hydraulic test facilities, research and development work, construction and operation of pilot and demonstration SNPPs, and finally, construction and more than 20 years of operation of the commercial SNPP, namely Bilibino nuclear co-generation plant (NCGP) located in Chukotka autonomous district, which is one of the most remote regions in the far north-east of Russia. In recent years, studies have been carried out on the development of several new SNPP designs using advanced reactors of the new generation. Among these are the second stage of Bilibino NCGP, floating NCGP VOLNOLOM-3, designated for siting in the Arctic sea coast area, and a nuclear district heating plant for the town of Apatity, in the Murmansk region. In this paper, the background and current status of the SNPPs are given, and the problems as well as prospects of small nuclear reactors development and implementation are considered. (orig.) 20 refs.

  3. Climatic effects of nuclear war

    International Nuclear Information System (INIS)

    Turco, R.P.; Toon, O.B.; Ackerman, T.P.; Pollack, J.B.; Sagan, C.

    1984-01-01

    Recent findings by this group confirmed by workers in Europe, the US and the USSR, suggest that the long-term climatic effects of a major nuclear war are likely to be much severer and farther-reaching than had been supposed. In the aftermath of such a war vast areas of the earth could be subjected to prolonged darkness, abnormally low temperatures, violent windstorms, toxic smog and persistent radioactive fallout - in short, the combination of conditions that has come to be known as nuclear winter. In brief, the authors' initial results, published in Science in December, 1983, showed that the potential global atmospheric and climatic consequences of nuclear war...are serious. Significant hemispherical attenuation of the solar radiation flux and subfreezing land temperatures may be caused by fine dust raised in high-yield nuclear surface bursts and by smoke from city and forest fires ignited by airbursts of all yields. Subsequent studies, based on more powerful models of the general circulation of the earth's atmosphere, have tended to confirm both the validity of the authors' investgative approach and the main thrust of their findings. Most of this article is devoted to reviewing the current state of knowledge on this vital issue

  4. Economic effect of applied nuclear-agricultural science in China

    International Nuclear Information System (INIS)

    Ji Xiaobing; Zhou Zhihong; Zhao Shoufeng

    1998-01-01

    The economic effect of applied nuclear-agricultural science for 40 years in China have been summarized, analyzed and appraised. The economic regularity and features which are followed by research-development-production in the field of applied nuclear agricultural science in China are explored according to the essential characteristics of economics for input-output ratio and the itself-features of nuclear agricultural science. Some propositions for promoting the development and the economic effect of the applied nuclear-agricultural science in China are also given

  5. Mean-field theory of nuclear structure and dynamics

    International Nuclear Information System (INIS)

    Negele, J.W.

    1982-01-01

    The physical and theoretical foundations are presented for the mean-field theory of nuclear structure and dynamics. Salient features of the many-body theory of stationary states are reviewed to motivate the time-dependent mean-field approximation. The time-dependent Hartree-Fock approximation and its limitations are discussed and general theoretical formulations are presented which yield time-dependent mean-field equations in lowest approximation and provide suitable frameworks for overcoming various conceptual and practical limitations of the mean-field theory. Particular emphasis is placed on recent developments utilizing functional integral techniques to obtain a quantum mean-field theory applicable to quantized eigenstates, spontaneous fission, the nuclear partition function, and scattering problems. Applications to a number of simple, idealized systems are presented to verify the approximations for solvable problems and to elucidate the essential features of mean-field dynamics. Finally, calculations utilizing moderately realistic geometries and interactions are reviewed which address heavy-ion collisions, fusion, strongly damped collisions, and fission

  6. The Nordic safety programme in the nuclear field

    International Nuclear Information System (INIS)

    Wahlstroem, B.; Marcus, F.

    1987-01-01

    Safety of nuclear installations has been a concern of all the Nordic countries, although only Finland and Sweden have selected to build nuclear power plants. It was recognized early that the resources in a single country were limited and previous Nordic cooperation in the nuclear field was therefore followed up through a safety programme which started ten years ago. This research cooperation has been intensified during the years, and today more than 70 organizations in Denmark, Finland, Norway, and Sweden participate. The present programme is the third in a row and it will continue until 1989. Human factors and operational experience are touched upon in the RAS (safety philosophy) and the INF (advanced information technology) subprogrammes. The paper gives a brief overview of the Nordic safety programme in general and the RAS and INF subprogrammes. 11 refs. (author)

  7. Organic tunnel field effect transistors

    KAUST Repository

    Tietze, Max Lutz; Lussem, Bjorn; Liu, Shiyi

    2017-01-01

    Various examples are provided for organic tunnel field effect transistors (OTFET), and methods thereof. In one example, an OTFET includes a first intrinsic layer (i-layer) of organic semiconductor material disposed over a gate insulating layer

  8. Research study on public relations and public participation in the nuclear energy field

    International Nuclear Information System (INIS)

    Gunji, Ikuko; Tabata, Rimiko; Otoshi, Sachio; Kuwagaki, Reiko; Ishibashi, Yoichiro

    2006-01-01

    The purpose of this research is to clarify the effect of public relations activities in the nuclear energy field and public participation toward the improvement of the risk literacy of nuclear energy. According to the survey results of the actual public relations activities taken by nuclear energy industry, the opportunity for interactive communications between the public and the industry is insufficient. Consequently, we propose building up more opportunities for participation and collaboration of citizens and industries in order to improve interactive communications reflecting public opinions and points of view. (author)

  9. The Effects of Nuclear Weapons

    Energy Technology Data Exchange (ETDEWEB)

    Glasstone, Samuel

    1957-06-01

    This handbook prepared by the Armed Forces Special Weapons Project of the Department of Defense in coordination with other cognizant government agencies and published by the United States Atomic Energy Commission, is a comprehensive summary of current knowledge on the effects of nuclear weapons. The effects information contained herein is calculated for yields up to 20 megatons and the scaling laws for hypothetically extending the calculations beyond this limit are given. The figure of 20 megatons however is not be taken as an indication of capabilities or developments.

  10. Nordic projects in the field of nuclear safety

    International Nuclear Information System (INIS)

    Soerensen, H.C.

    1988-05-01

    This report deseribes the work in 1987 within the Nordic program concerning nuclear safety 1985-1989. The report has the form of a handbook meant for those in Scandinavia who are involved in nuclear safety, and it is based on statements from the constituent subject fields of the program. The first chapter is a short summary of the work and results over the year. In the next chapter an account is given of the ongoing projects within each of the subject fields. An economic survey of the entire program and a list of the reports and articles published in 1987 is included in the publication as well. Chapter 5 is a complete list of adresses comprising participants, project managers, program coordinators and members of the advisory group. (SH) 74 refs

  11. Nordic projects in the field of nuclear safety

    International Nuclear Information System (INIS)

    Soerensen, H.C.

    1989-07-01

    This report describes the work in 1988 within the Nordic program concerning nuclear safety 1985-1989. The report has the form of a handbook meant for those in Scandinavia who are involeved in nuclear safety, and it is based on statements from the constituent subject fields of the program. The first chapter is a short summary of the work and results over the year. In the next chapter an account is given of the ongoing projects within each of the subject fields. An economic survey of the entire program and a list of the reports and articles published in 1988 is included in the publicaltion as well. Chapter 5 is a complete list of adresses comprising participants, project managers, program coordinators and members of the advirosy group. (SH)

  12. Magnetic field effects in proteins

    Science.gov (United States)

    Jones, Alex R.

    2016-06-01

    Many animals can sense the geomagnetic field, which appears to aid in behaviours such as migration. The influence of man-made magnetic fields on biology, however, is potentially more sinister, with adverse health effects being claimed from exposure to fields from mobile phones or high voltage power lines. Do these phenomena have a common, biophysical origin, and is it even plausible that such weak fields can profoundly impact noisy biological systems? Radical pair intermediates are widespread in protein reaction mechanisms, and the radical pair mechanism has risen to prominence as perhaps the most plausible means by which even very weak fields might impact biology. In this New Views article, I will discuss the literature over the past 40 years that has investigated the topic of magnetic field effects in proteins. The lack of reproducible results has cast a shadow over the area. However, magnetic field and spin effects have proven to be useful mechanistic tools for radical mechanism in biology. Moreover, if a magnetic effect on a radical pair mechanism in a protein were to influence a biological system, the conditions necessary for it to do so appear increasing unlikely to have come about by chance.

  13. Quark mean field theory and consistency with nuclear matter

    International Nuclear Information System (INIS)

    Dey, J.; Tomio, L.; Dey, M.; Frederico, T.

    1989-01-01

    1/N c expansion in QCD (with N c the number of colours) suggests using a potential from meson sector (e.g. Richardson) for baryons. For light quarks a σ field has to be introduced to ensure chiral symmetry breaking ( χ SB). It is found that nuclear matter properties can be used to pin down the χ SB-modelling. All masses, M Ν , m σ , m ω are found to scale with density. The equations are solved self consistently. (author)

  14. Foundation field bus in the Spanish nuclear sector; Foundation fieldbus en el sector nuclear espanol

    Energy Technology Data Exchange (ETDEWEB)

    Saez de Montagut Revenga, G.

    2013-07-01

    This paper deals with the modification made in power plants nuclear ASCO 1 and 2 in which scans is the level Control system of Heaters to implementing an Ovation system, as well as the standard Foundation Field bus for field communications. This digitalisation has required a detailed study of the implications on security that could have the centralization of control loops in main feedwater system.

  15. Effective Giromagnetic Ratios in Artifical Nuclear Magnetization Pumping of the Noble Gases Mix

    Directory of Open Access Journals (Sweden)

    Popov E.N.

    2015-01-01

    Full Text Available Dynamic of the nuclear magnetization of the two noble gases mix was studied in this research. Nuclear magnetization pumped along the induction of external magnetic field. Vector of nuclear magnetization is given a tilt by the week rotational magnetic field, which makes NMR for noble gases. Interaction between the nuclear magnetic moments of the different noble gases adducted to shifts at the frequency of nuclear moments precession in external magnetic field. Effective gyromagnetic ratios of the nuclear of noble gases is defined and it different from the tabulated value. There is theoretical calculation of effective gyromagnetic ratios in this research.

  16. Ligand field effects in the nuclear magnetic shielding of nitrogen-15 and cobalt-59 in bent nitrosyl complexes of cobalt(III)

    International Nuclear Information System (INIS)

    Duffin, P.A.; Larkworthy, L.F.; Mason, J.; Stephens, A.N.; Thompson, R.M.

    1987-01-01

    A range of square-pyramidal complexes of cobalt(III) with a bent apical nitrosyl ligand has been prepared and examined by 15 N and 59 Co NMR spectroscopy, in a study of nephelauxetic and spectrochemical effects at the metal and nitrogen nuclei in the bent Co-NO chromophore. The basal ligands in this comparison include dithiocarbamate, quadridentate Schiff base or porphine, and bis-chelating diamine or oximate, so as to give S 4 , S 2 N 2 , N 4 , OONN, or ONON coordination in the plane and a range of substituents in the chelate and phenylene rings. The shielding of both cobalt and nitrogen tends to decrease with decrease in the M(d) → π*(NO) back-bonding, as indicated by the MN and NO bond distances, the MNO angle and the NO stretching frequency. The shieldings decrease from sulfur to nitrogen to oxygen coligators and also with electron withdrawal by ring substituents (and vice versa), i.e. with decrease in the ligand field splitting and in the nephelauxetism of the coligands. These parallelisms of the cobalt and nitrogen shielding accord with the orbital theory that was developed to explain the bending of the MNO ligand and influences of the metal and coligands. Significant interdependence of spectrochemical and nephelauxetic effects at cobalt and nitrogen arises from the degree of overlap and similarity in energies of the frontier orbitals for the paramagnetic circulation at nitrogen [n(N) → π* (NO)] and at cobalt (d-d). 43 references, 5 figures, 2 tables

  17. Climatic effects of nuclear war

    International Nuclear Information System (INIS)

    Crutzen, P.J.

    1987-01-01

    Although considerable further research has been conducted since the writing of the Scientific Committee on Problems of the Environment (SCOPE) study, the main conclusions reached in early 1986 about the potential climatic, atmospheric, chemical, ecological, and agricultural consequences of a nuclear war are still valid, also taking into account the latest research results by Thompson and Schneider (1986). The main finding of the SCOPE study is that severe, large-scale, possibly global, climatic disturbances could result from a nuclear war in which a substantial fraction (10% or more) of the combustible materials in the NATO and Warsaw Pact nations would burn, producing several tens of million tonnes of soot. This could be caused by nuclear attacks on less than a hundred of the most important urban and industrial centres of these nations. As a consequence, it is estimated that surface temperatures might drop by more than 10 deg. C over a large fraction of the continents in the northern hemisphere and that rainfall could also be strongly reduced. These effects could last for weeks, maybe years. In many parts of the northern hemisphere agricultural productivity would be severely reduced, contributing to serious food shortages. 37 refs, 5 figs, 4 tabs

  18. Quark distributions in nuclear matter and the EMC effect

    Energy Technology Data Exchange (ETDEWEB)

    Mineo, H.; Bentz, W. E-mail: bentz@keyaki.cc.u-tokai.ac.jp; Ishii, N.; Thomas, A.W.; Yazaki, K

    2004-05-03

    Quark light cone momentum distributions in nuclear matter and the structure function of a bound nucleon are investigated in the framework of the Nambu-Jona-Lasinio model. This framework describes the nucleon as a relativistic quark-diquark state, and the nuclear matter equation of state by using the mean field approximation. The scalar and vector mean fields in the nuclear medium couple to the quarks in the nucleon and their effect on the spin independent nuclear structure function is investigated in detail. Special emphasis is placed on the important effect of the vector mean field and on a formulation which guarantees the validity of the number and momentum sum rules from the outset.

  19. Ultrasonic field analysis program for transducer design in the nuclear industry

    International Nuclear Information System (INIS)

    Singh, G.P.; Rose, J.L.

    1980-02-01

    An ultrasonic field analysis program is presented that can be used for transducer design in the nuclear industry. Calculation routines that make use of Huygen's principle in a field analysis model are introduced that enable such field characteristics as axial and lateral resolution, beam symmetry, and gain variation throughout the ultrasonic field to be optimized. Mathematical details are presented along with several sample problems that show comparisons with classical results reported in the literature and with experimental data. Several sample problems that are of interest to the nuclear industry are also included, along with some that satisfy both academical and practical curiosity. These include transducer shape effects, pulse shape effects, crystal vibration variation, and an introduction to such novel transducer designs as annular arrays and dual element angle beam transducers

  20. Status of Korean nuclear industry and Romania-Korea cooperation in the field of nuclear power

    International Nuclear Information System (INIS)

    Lee, Myung Key

    2005-01-01

    The Kyoto Protocol on climate change has urged the world to explore ways of cutting down the greenhouse emissions, and it also boosted a number of nuclear power projects that is so-called the renaissance of nuclear power. Nuclear power has proven to be the cleanest energy source and one of the cheapest types of energies, compared with other energy sources. Korea began developing its nuclear power projects from the early 1970's. Since the first nuclear power plant Kori Unit 1, started commercial operation in 1978, Korea has continuously promoted the development of nuclear power projects, and today it operates 20 nuclear power units (17,716 MW), including 4 units of CANDU plants. Korea ranked No. 6 in the world in terms of installed capacity of nuclear power plants, and 40% of its domestic electricity generation comes from nuclear power plants. The average plant capacity factor was 95.5% in 2005, which is about 16% than the world average of around 79%. All the Korean nuclear power projects are led and implemented by Korea Hydro and Nuclear Power Co. (KHNP) which is the sole state-owned nuclear power project company spun off from Korea Electric Power Corporation (KEPCO) in 2001 as part of the government's program for electric industry restructuring. The cooperation between Romania and Korea in the nuclear power field began in March 2001. At industrial level a technical agreement between the Romanian Company Nuclearelectrica S.A. (SNN) and KHNP was signed in July 2003 for cooperation in Cernavoda NPP projects. The joint development of the Cernavoda NPP unit 3 was one of the major topics. Heavy water produced by Romanian Heavy Water plant at Drobeta Turnu Severin was supplied to KHNP (16 tones in 2001 and another 16 tones in 2004). The feasibility study for units 3 and 4 is being performed in two phases under leadership of SNN in cooperation with KHNP, AECL, ANSALDO and Deloitte and Touche as a financial advisor in Phase 2. It is expected that the appropriate securities

  1. Health and environmental effects of nuclear weapons

    International Nuclear Information System (INIS)

    1993-01-01

    This report briefly reviews previous WHO work on the health consequences of nuclear war and concentrates on current information about the effects of nuclear weapons on health, and related environmental problems. 15 refs

  2. Overview of climatic effects of nuclear winter

    International Nuclear Information System (INIS)

    Jones, E.M.; Malone, R.C.

    1985-01-01

    A general description of the climatic effects of a nuclear war are presented. This paper offers a short history of the subject, a discussion of relevant parameters and physical processes, and a description of plausible nuclear winter scenario. 9 refs

  3. Nuclear β decay with a massive neutrino in an external electromagnetic field

    International Nuclear Information System (INIS)

    Ternov, I.M.; Rodionov, V.N.; Zhulego, V.G.; Lobanov, A.E.; Pavlova, O.S.; Dorofeev, O.F.

    1986-01-01

    Beta decay in the presence of an external electromagnetic field is investigated, taking into account the non-zero neutrino rest mass. The spectrum of electrons and polarisation effects of different orientations of nuclear spin are considered. It is shown that the electromagnetic wave substantially modifies the boundaries of the spectrum of β electrons. The results, which include an analysis of the total decay probability in intense magnetic fields, may have various astrophysical implications. (author)

  4. Nuclear famine: The indirect effects of nuclear war

    International Nuclear Information System (INIS)

    Harwell, M.A.; Harwell, C.C.

    1986-01-01

    The indirect effects of a nuclear war, especially as mediated by disruption in food availability, could be much more extensive than the direct effects. Furthermore, this risk is especially severe for noncombatant countries - for the 4 billion or so humans expected to survive the immediate period after a nuclear war relatively physically unharmed. Thus, a fundamentally different picture of the post-nuclear-war world results, where a large-scale nuclear war between the United States and the Soviet Union would probably result in more eventual fatalities in India than in the United States and the Soviet Union combined, and more people would die on the African continent than in all of Europe. Rather than reflecting images of Hiroshima and Nagasaki, a modern nuclear war would, for most of the people of the world, much more resemble current images of Ethiopia and the Sudan

  5. Quark effects in nuclear physics

    International Nuclear Information System (INIS)

    Scholten, O.

    1990-01-01

    The magnitude of the quark effect for low-energy nuclear physics is investigated. Coulomb energy is studied in the A=3 system in order to determine the effect of the composite structure of the nucleon. In the actual calculations a non-relativistic quark-cluster model description has been used. A nucleon size b=0.617 fm, the width of the relative wave function Φ of the quarks in the nucleon, has been assumed. It is concluded that the contribution to Coulomb energies due to quark effects are significant compared to the observed Nolen-Schiffer anomaly. However these do not provide the long searched for 'smoking gun'. When the free parameters that appear in the calculation are adjusted to reproduce the same charge form factor, the calculated anomalies are not significantly different. 2 figs., 2 tabs., 8 refs.2

  6. Quantum effects in strong fields

    International Nuclear Information System (INIS)

    Roessler, Lars

    2014-01-01

    This work is devoted to quantum effects for photons in spatially inhomogeneous fields. Since the purely analytical solution of the corresponding equations is an unsolved problem even today, a main aspect of this work is to use the worldline formalism for scalar QED to develop numerical algorithms for correlation functions beyond perturbative constructions. In a first step we take a look at the 2-Point photon correlation function, in order to understand effects like vacuum polarization or quantum reflection. For a benchmark test of the numerical algorithm we reproduce analytical results in a constant magnetic background. For inhomogeneous fields we calculate for the first time local refractive indices of the quantum vacuum. In this way we find a new de-focusing effect of inhomogeneous magnetic fields. Furthermore the numerical algorithm confirms analytical results for quantum reflection obtained within the local field approximation. In a second step we take a look at higher N-Point functions, with the help of our numerical algorithm. An interesting effect at the level of the 3-Point function is photon splitting. First investigations show that the Adler theorem remains also approximately valid for inhomogeneous fields.

  7. The effects of nuclear weapons

    International Nuclear Information System (INIS)

    Barnaby, F.; Rotblat, J.

    1982-01-01

    At least 40% of the population of Hiroshima and 26% of that of Nagasaki were killed in the nuclear attacks. The early and late effects in these two cities and in relation to present weaponry are briefly discussed. The effects of blast, heat and initial and delayed radiation are outlined. Neutron and gamma doses as functions of slant distances for bombs of various specified yields are presented. Dose rates for fallout at various times after explosions in terms of wind velocity and various cloud formations are also outlined. In Western Europe there are only 145 cities with populations of over 200,000. It is concluded that the destruction of these cities would kill in a short time more than one third of the population of Western Europe, and in a nuclear world war, not only would a fair part of the urban population in the Northern Hemisphere be killed by fire and blast, and most of the survivors by radiation, but much of the rural population would be killed by radiation from fallout. Many millions in the Southern Hemisphere would also be killed by fallout radiation. (U.K.)

  8. The Effects of Nuclear Weapons. Third edition

    Energy Technology Data Exchange (ETDEWEB)

    Glasstone, S; Dolan, P J

    1977-01-01

    Since the last edition of ''The Effects of Nuclear Weapons'' in 1962 much new information has become available concerning nuclear weapon effects. This has come in part from the series of atmospheric tests, including several at very high altitudes, conducted in the Pacific Ocean area in 1962. In addition, laboratory studies, theoretical calculations, and computer simulations have provided a better understanding of the various effects. A new chapter has been added on the electromagnetic pulse. The chapter titles are as follows: general principles of nuclear explosions; descriptions of nuclear explosions; air blast phenomena in air and surface bursts; air blast loading; structural damage from air blast; shock effects of surface and subsurface bursts; thermal radiation and its effects; initial nuclear radiation; residual nuclear radiation and fallout; radio and radar effects; the electromagnetic pulse and its effects; and biological effects. (LTN)

  9. Tunneling field effect transistor technology

    CERN Document Server

    Chan, Mansun

    2016-01-01

    This book provides a single-source reference to the state-of-the art in tunneling field effect transistors (TFETs). Readers will learn the TFETs physics from advanced atomistic simulations, the TFETs fabrication process and the important roles that TFETs will play in enabling integrated circuit designs for power efficiency. · Provides comprehensive reference to tunneling field effect transistors (TFETs); · Covers all aspects of TFETs, from device process to modeling and applications; · Enables design of power-efficient integrated circuits, with low power consumption TFETs.

  10. Graphene field-effect devices

    Science.gov (United States)

    Echtermeyer, T. J.; Lemme, M. C.; Bolten, J.; Baus, M.; Ramsteiner, M.; Kurz, H.

    2007-09-01

    In this article, graphene is investigated with respect to its electronic properties when introduced into field effect devices (FED). With the exception of manual graphene deposition, conventional top-down CMOS-compatible processes are applied. Few and monolayer graphene sheets are characterized by scanning electron microscopy, atomic force microscopy and Raman spectroscopy. The electrical properties of monolayer graphene sandwiched between two silicon dioxide films are studied. Carrier mobilities in graphene pseudo-MOS structures are compared to those obtained from double-gated Graphene-FEDs and silicon metal-oxide-semiconductor field-effect-transistors (MOSFETs).

  11. DC superconducting quantum interference device usable in nuclear quadrupole resonance and zero field nuclear magnetic spectrometers

    Science.gov (United States)

    Fan, Non Q.; Clarke, John

    1993-01-01

    A spectrometer for measuring the nuclear quadrupole resonance spectra or the zero-field nuclear magnetic resonance spectra generated by a sample is disclosed. The spectrometer uses an amplifier having a dc SQUID operating in a flux-locked loop for generating an amplified output as a function of the intensity of the signal generated by the sample. The flux-locked loop circuit includes an integrator. The amplifier also includes means for preventing the integrator from being driven into saturation. As a result, the time for the flux-locked loop to recover from the excitation pulses generated by the spectrometer is reduced.

  12. 1986 Agreement on third party liability in the nuclear field

    International Nuclear Information System (INIS)

    1986-01-01

    This Agreement intends to facilitate the settlement of disputes, if they are due to an event (caused by the peaceful utilisation of nuclear energy) which occurs on the territory of one State and gives rise to damage on the territory of the other State. Unlike the Federal Republic of Germany, Switzerland has neither ratified the Paris Convention of 29th July 1960 on Third Party Liability in the Field of Nuclear Energy nor the Brussels Supplementary Convention of 31st January 1963. This might result in diverging interpretations by the German and Swiss courts, in particular, regarding the competent courts and the laws applicable if a third party liability problem were to arise between both countries. The Agreement therefore aims to settle these matters directly by treaty between the States before the courts are confronted by an occurrence of damage and have to seek a solution which conforms to international private law. (NEA) [fr

  13. Mesonic effects in nuclear physics

    International Nuclear Information System (INIS)

    Johnson, M.

    1978-01-01

    The relation between mesons and nucleons and the properties of nuclear matter, as presently understood, is considered in these lectures. Feynman diagrams, meson theoretical nucleon-nucleon interactions, mesonic components in nuclear wave functions, direct observation of mesonic components in NN scattering above the pion production threshold, nuclear matter theory, and pion condensation are treated. 120 references

  14. Biological effects of electromagnetic fields

    International Nuclear Information System (INIS)

    David, E.

    1993-01-01

    In this generally intelligible article, the author describes at first the physical fundamentals of electromagnetic fields and their basic biological significance and effects for animals and human beings before dealing with the discussion regarding limiting values and dangers. The article treats possible connections with leukaemia as well as ith melatonine production more detailed. (vhe) [de

  15. Nonadiabatic effects in electronic and nuclear dynamics

    Directory of Open Access Journals (Sweden)

    Martin P. Bircher

    2017-11-01

    Full Text Available Due to their very nature, ultrafast phenomena are often accompanied by the occurrence of nonadiabatic effects. From a theoretical perspective, the treatment of nonadiabatic processes makes it necessary to go beyond the (quasi static picture provided by the time-independent Schrödinger equation within the Born-Oppenheimer approximation and to find ways to tackle instead the full time-dependent electronic and nuclear quantum problem. In this review, we give an overview of different nonadiabatic processes that manifest themselves in electronic and nuclear dynamics ranging from the nonadiabatic phenomena taking place during tunnel ionization of atoms in strong laser fields to the radiationless relaxation through conical intersections and the nonadiabatic coupling of vibrational modes and discuss the computational approaches that have been developed to describe such phenomena. These methods range from the full solution of the combined nuclear-electronic quantum problem to a hierarchy of semiclassical approaches and even purely classical frameworks. The power of these simulation tools is illustrated by representative applications and the direct confrontation with experimental measurements performed in the National Centre of Competence for Molecular Ultrafast Science and Technology.

  16. Application of radioisotopes in the field of nuclear medicine

    International Nuclear Information System (INIS)

    Nayak, D.; Lahiri, S.

    1999-01-01

    A comprehensive review has been made to discuss the role of various radionuclides of lanthanide series elements in the field of nuclear medicine. The role of several pharmaceuticals labeled with radiolanthanides and used for investigative purposes like measurement of cerebral blood flow, bone density measurement, bone marrow imaging, etc., have been described. The role of lanthanide radionuclides in radiation synovectomy, radioimmunotherapy, etc., have also been discussed. Methods of preparation of some representative radiopharmaceuticals like 153 Sm-EDTMP, 153 Sm-HYP, have been presented. An outline on the production of carrier free radioisotopes of lanthanide series elements has been given. (author)

  17. Quark mean field theory and consistency with nuclear matter

    International Nuclear Information System (INIS)

    Dey, J.; Dey, M.; Frederico, T.; Tomio, L.

    1990-09-01

    1/N c expansion in QCD (with N c the number of colours) suggests using a potential from meson sector (e.g. Richardson) for baryons. For light quarks a σ field has to be introduced to ensure chiral symmetry breaking ( χ SB). It is found that nuclear matter properties can be used to pin down the χ SB-modelling. All masses, M N , m σ , m ω are found to scale with density. The equations are solved self consistently. (author). 29 refs, 2 tabs

  18. Incineration in the nuclear field. The SGN experience

    International Nuclear Information System (INIS)

    Carpentier, S.

    1993-01-01

    The operation of power reactors, like that of fuel fabrication and nuclear fuel reprocessing plants, generated substantial quantities of waste. A large share of this waste is low- and medium-level waste, which is also combustible. Similarly, a number of institutes, laboratories, and hospitals, in the course of their activities, generated waste which a portion is radioactive and combustible. The chief advantage of incineration is to minimize the volume of burnable waste treated, and to produce a residue termed 'ash'. SGN has built up 25 years of experience in this field. The incinerators have been designed and the incineration processes are specially studied by SGN

  19. Synaptic Effects of Electric Fields

    Science.gov (United States)

    Rahman, Asif

    Learning and sensory processing in the brain relies on the effective transmission of information across synapses. The strength and efficacy of synaptic transmission is modifiable through training and can be modulated with noninvasive electrical brain stimulation. Transcranial electrical stimulation (TES), specifically, induces weak intensity and spatially diffuse electric fields in the brain. Despite being weak, electric fields modulate spiking probability and the efficacy of synaptic transmission. These effects critically depend on the direction of the electric field relative to the orientation of the neuron and on the level of endogenous synaptic activity. TES has been used to modulate a wide range of neuropsychiatric indications, for various rehabilitation applications, and cognitive performance in diverse tasks. How can a weak and diffuse electric field, which simultaneously polarizes neurons across the brain, have precise changes in brain function? Designing therapies to maximize desired outcomes and minimize undesired effects presents a challenging problem. A series of experiments and computational models are used to define the anatomical and functional factors leading to specificity of TES. Anatomical specificity derives from guiding current to targeted brain structures and taking advantage of the direction-sensitivity of neurons with respect to the electric field. Functional specificity originates from preferential modulation of neuronal networks that are already active. Diffuse electric fields may recruit connected brain networks involved in a training task and promote plasticity along active synaptic pathways. In vitro, electric fields boost endogenous synaptic plasticity and raise the ceiling for synaptic learning with repeated stimulation sessions. Synapses undergoing strong plasticity are preferentially modulated over weak synapses. Therefore, active circuits that are involved in a task could be more susceptible to stimulation than inactive circuits

  20. Groundwater Waves in a Coastal Fractured Aquifer of the Third Phase Qinshan Nuclear Power Engineering Field

    Institute of Scientific and Technical Information of China (English)

    ZHOU Nian-qing; TANG Yi-qun; TANG He-ping

    2005-01-01

    Tidal fluctuations of Hangzhou Bay produce progressive pressure waves in adjacent field fractured aquifers, as the pressure waves propagate, groundwater levels and hydraulic gradients continuously fluctuate. The effect of tidal fluctuations on groundwater flow can be determined using the mean hydraulic gradient that can be calculated by comparing mean ground and surface water elevations. Tidal fluctuation is shown to affect the piezometer readings taken in a nearshore fractured aquifer around the nuclear power engineering field. Continuous monitoring of a network of seven piezometers provided relations between the tidal cycle and the piezometer readings. The relations can be expressed in times of a time and amplitude scaling factor. The time lag and the tidal effi ciency factor and wavelength are calculated using these parameters. It provides significant scientific basis to prevent tide and groundwater for the nuclear power engineering construction and safety run of nuclear power station in the future.

  1. System and Field Devices (non Nuclear) in Agriculture Research in Malaysian Nuclear Agency

    International Nuclear Information System (INIS)

    Shyful Azizi Abdul Rahman; Abdul Rahim Harun

    2015-01-01

    Research to improve productivity on an ongoing basis in the agricultural sector is essential to ensure and guarantee the country's food security. Malaysian Nuclear Agency, agricultural research had begun in 1981 in which the focus of research is related to mutation breeding, irradiation and the use of isotopes in the study of plant nutrition. Although projects agricultural research carried out based on nuclear technology, other information relating to agricultural research such as agronomy, plant physiology, meteorology and ecology, soil characteristics and water is essential to obtain the understanding and research results that are relevant and significant. Data acquisition for other aspects also need a system and a modern and efficient equipment, in accordance with current technological developments. This paper describes the use, function and capabilities of the existing field equipment available in Agrotechnology and Biosciences Division, Malaysian Nuclear Agency in acquiring data related to weather, measurement and control of ground water, soil nutrients assessment and monitoring of plant physiology. The latest technological developments in sensor technology, computer technology and communication is very helpful in getting data more easily, quickly and accurately. Equipment and the data obtained is also likely to be used by researchers in other fields in Nuclear Malaysia. (author)

  2. Intelligent SSCs as part of new era in nuclear field and new generation of nuclear facilities

    International Nuclear Information System (INIS)

    Florescu, Gheorghe; Agapi, Constantin; Panaitescu, V.; Florescu, Ioan-Bogdan

    2008-01-01

    Nuclear field being in a continuous process of changing and development, offers the opportunity of incorporation of many new designed SSCs and new methods and techniques of study and analysis. Due to the complex items involved in this industrial sector, the nuclear area was always a field of promoting new achievement in hardware science and technique. A major issue in the nuclear facilities is the very large number of not monitored SSCs and also the very large number of undiscovered degraded SSCs. Critical SSCs, referring both to operation and safety, is very important to be monitored. Visual contact and inspections are time and resources consuming and access is not always possible. The evolution of electronics and development of advanced data acquisition devices offers the possibility of use of such equipment to many applications. Methods of investigations of nuclear facilities operation are diverse, deterministic and probabilistic techniques are usually applied. The paper presents the main disadvantages, concerning to the possibility of rapid identification of malfunctions of actual SSCs design. A special section is dedicated to intelligent sensors and SSCs. (authors)

  3. Time characteristics of photon fields at a nuclear medicine clinic

    International Nuclear Information System (INIS)

    Zimak, J.; Hermanska, J.; Sabol, J.

    1998-01-01

    The radiation fields were measured at the Nuclear Medicine Clinic of the Faculty Hospital in Prague-Motol. Gamma photons from iodine 131 administered to the patients is the main contributor to the fields. The dose rates at short distances from the patients can be as high as 20 mSv/h, whereby the cumulated doses to the health care personnel can exceed the annual limits for professional exposures. It is very important that unnecessary close contact with the patients be avoided unless emergency of other urgent procedures are required. Administration of high activities to several patients sharing a room in the ward should also be taken into account when handling the patients (including food service, housekeeping, changing linen, etc.). In normal circumstances, the radiation level in corridors and at other places accessible to cancer patients within the clinic are usually below 5 μSv/h averaged for 1 min intervals. (P.A.)

  4. Procedures for field measurements in the case of nuclear accident

    International Nuclear Information System (INIS)

    Barisic, D.; Lulic, S.

    2000-01-01

    Very simplified, reduced and shorted procedures for main objectives of emergency field monitoring in case of nuclear accident are given only. They could be implemented in Croatia using resources nowadays available. Procedures for gamma/beta dose rates in plume and ground deposition survey and unknown situation evaluation, procedures for alpha and gamma/beta surface contamination measurement, field personnel/equipment contamination and decontamination measurement as well as for in-situ gamma spectrometry measurements are presented. Purpose, short discussion, general precautions and limitations as well as basic equipment and supplies needed are given for all of procedures discussed also. Only measuring steps are given with more details in form of short and clear instructions. (author)

  5. Nuclear threshold effects and neutron strength function

    International Nuclear Information System (INIS)

    Hategan, Cornel; Comisel, Horia

    2003-01-01

    One proves that a Nuclear Threshold Effect is dependent, via Neutron Strength Function, on Spectroscopy of Ancestral Neutron Threshold State. The magnitude of the Nuclear Threshold Effect is proportional to the Neutron Strength Function. Evidence for relation of Nuclear Threshold Effects to Neutron Strength Functions is obtained from Isotopic Threshold Effect and Deuteron Stripping Threshold Anomaly. The empirical and computational analysis of the Isotopic Threshold Effect and of the Deuteron Stripping Threshold Anomaly demonstrate their close relationship to Neutron Strength Functions. It was established that the Nuclear Threshold Effects depend, in addition to genuine Nuclear Reaction Mechanisms, on Spectroscopy of (Ancestral) Neutron Threshold State. The magnitude of the effect is proportional to the Neutron Strength Function, in their dependence on mass number. This result constitutes also a proof that the origins of these threshold effects are Neutron Single Particle States at zero energy. (author)

  6. Slovenian Experience as the EU Candidate Country in the Field of Nuclear Energy and Nuclear Safety

    International Nuclear Information System (INIS)

    Grlicarev, I.

    2002-01-01

    Slovenia was the first EU acceding country which has managed to successfully reach consensus with the European Commission (EC) on the chapters Energy, which comprises nuclear energy, and Environment, which comprises nuclear safety and radiation protection. This practically meant that the EU adopted the position that these two chapters did not, at that stage, require further negotiation. The EC will continue to monitor the progress in adoption and implementation of the EU legislation throughout the negotiations. The activities in relation to the accession of Slovenia to the EU in the area of nuclear energy and nuclear safety are reflected in the transposition of the legislation and establishing the institutions capable of implementing the EU legislation. The importance of regular reporting to the EC on the status is vital for monitoring the progress. The EC issues progress reports for all candidate countries on annual basis and the action plan has been devised by the EC to put some extra pressure on the candidate countries. The position of the EU in the area of nuclear legislation is reflected in the so called Non-binding EU acquis. The actual position of the EU towards each Candidate Country and to these countries as a whole is contained in the document Report on Nuclear Safety in the Context of the Enlargement. The Act on Nuclear and Radiation Safety had been drafted and is planned to be passed by the Parliament in the first half of 2002. The EC is willing to provide support in implementation of projects to strengthen nuclear safety in Slovenia (assistance to the regulatory authority, review of seismic studies, support with the periodic safety review, review and application of PSA studies). The recent status in the preparation of the position of Slovenia in negotiations in to the EU in the field of nuclear energy, nuclear safety and radiation protection shows that Slovenia has still some tasks to be done, but there are no pending issues which might hinder the

  7. Organization of multinational undertakings in the nuclear field

    International Nuclear Information System (INIS)

    Yajima, Masayuki

    1982-01-01

    Various proposals have been put forward to establish multinational undertakings for enrichment, fuel fabrication, reprocessing, spent fuel storage and waste management. The purpose of this paper is to investigate the legal, institutional framework aspects of multinational undertakings in the field of nuclear fuel cycle. The selection of the appropriate bodies representing the interest of participating countries would largely depend on the object or role of multinational undertakings. Regarding the principle of formation, URENCO is a much informative model of formation, which distinguishes the equity participation at national level and multinational level. The allocation of service between equity participants and non-equity participants depends on the objective of establishing business. Some priority in service allocation should be given to equity participants, and the participants having non-proliferation objective may require service allocation to avoid proliferation risk. The degree of achieving non-proliferation goal is related to the scope of participation. The experience in the field of nuclear energy seems to suggest that the concept of two-tiered decisionmaking structure is generally accepted. Various legal instruments appropriate to constitute multinational fuel cycle arrangement were examined, referring to the precedents and experience. (Kako, I.)

  8. A brief review of advances in complex networks of nuclear science and technology field

    International Nuclear Information System (INIS)

    Fang Jinqing

    2010-01-01

    A brief review of advances in complex networks of nuclear science and technology field at home and is given and summarized. These complex networks include: nuclear energy weapon network, network centric warfare, beam transport networks, continuum percolation evolving network associated with nuclear reactions, global nuclear power station network, (nuclear) chemistry reaction networks, radiological monitoring and anti-nuclear terror networks, and so on. Some challenge issues and development prospects of network science are pointed out finally. (authors)

  9. Rotating-frame gradient fields for magnetic resonance imaging and nuclear magnetic resonance in low fields

    Science.gov (United States)

    Bouchard, Louis-Serge; Pines, Alexander; Demas, Vasiliki

    2014-01-21

    A system and method for Fourier encoding a nuclear magnetic resonance (NMR) signal is disclosed. A static magnetic field B.sub.0 is provided along a first direction. An NMR signal from the sample is Fourier encoded by applying a rotating-frame gradient field B.sub.G superimposed on the B.sub.0, where the B.sub.G comprises a vector component rotating in a plane perpendicular to the first direction at an angular frequency .omega.in a laboratory frame. The Fourier-encoded NMR signal is detected.

  10. Nuclear reaction inputs based on effective interactions

    Energy Technology Data Exchange (ETDEWEB)

    Hilaire, S.; Peru, S.; Dubray, N.; Dupuis, M.; Bauge, E. [CEA, DAM, DIF, Arpajon (France); Goriely, S. [Universite Libre de Bruxelles, Institut d' Astronomie et d' Astrophysique, CP-226, Brussels (Belgium)

    2016-11-15

    Extensive nuclear structure studies have been performed for decades using effective interactions as sole input. They have shown a remarkable ability to describe rather accurately many types of nuclear properties. In the early 2000 s, a major effort has been engaged to produce nuclear reaction input data out of the Gogny interaction, in order to challenge its quality also with respect to nuclear reaction observables. The status of this project, well advanced today thanks to the use of modern computers as well as modern nuclear reaction codes, is reviewed and future developments are discussed. (orig.)

  11. Hanle effect in (In,Ga)As quantum dots: Role of nuclear spin fluctuations

    OpenAIRE

    Kuznetsova, M. S.; Flisinski, K.; Gerlovin, I. Ya.; Ignatiev, I. V.; Kavokin, K. V.; Verbin, S. Yu.; Yakovlev, D. R.; Reuter, D.; Wieck, A. D.; Bayer, M.

    2013-01-01

    The role of nuclear spin fluctuations in the dynamic polarization of nuclear spins by electrons is investigated in (In,Ga)As quantum dots. The photoluminescence polarization under circularly polarized optical pumping in transverse magnetic fields (Hanle effect) is studied. A weak additional magnetic field parallel to the optical axis is used to control the efficiency of nuclear spin cooling and the sign of nuclear spin temperature. The shape of the Hanle curve is drastically modified with cha...

  12. Effective potentials for twisted fields

    International Nuclear Information System (INIS)

    Banach, R.

    1981-01-01

    Minus the density of the effective action, evaluated at the lowest eigenfunction of the (space-time) derivative part of the second (functional) derivative of the classical action, is proposed as a generalised definition of the effective potential, applicable to twisted as well as untwisted sectors of a field theory. The proposal is corroborated by several specific calculations in the twisted sector, namely phi 4 theory (real and complex) and wrong-sign-Gordon theory, in an Einstein cylinder, where the exact integrability of the static solutions confirms the effective potential predictions. Both models exhibit a phase transition, which the effective potential locates, and the one-loop quantum shift in the critical radius is computed for the real phi 4 model, being a universal result. Topological mass generation at the classical level is pointed out, and the exactness of the classical effective potential approximation for complex phi 4 is discussed. (author)

  13. Effective field theory dimensional regularization

    International Nuclear Information System (INIS)

    Lehmann, Dirk; Prezeau, Gary

    2002-01-01

    A Lorentz-covariant regularization scheme for effective field theories with an arbitrary number of propagating heavy and light particles is given. This regularization scheme leaves the low-energy analytic structure of Greens functions intact and preserves all the symmetries of the underlying Lagrangian. The power divergences of regularized loop integrals are controlled by the low-energy kinematic variables. Simple diagrammatic rules are derived for the regularization of arbitrary one-loop graphs and the generalization to higher loops is discussed

  14. Effective field theory dimensional regularization

    Science.gov (United States)

    Lehmann, Dirk; Prézeau, Gary

    2002-01-01

    A Lorentz-covariant regularization scheme for effective field theories with an arbitrary number of propagating heavy and light particles is given. This regularization scheme leaves the low-energy analytic structure of Greens functions intact and preserves all the symmetries of the underlying Lagrangian. The power divergences of regularized loop integrals are controlled by the low-energy kinematic variables. Simple diagrammatic rules are derived for the regularization of arbitrary one-loop graphs and the generalization to higher loops is discussed.

  15. Status of Korean nuclear industry and Romania-Korea cooperation in nuclear field

    International Nuclear Information System (INIS)

    Myung-Key, Lee

    2005-01-01

    , constructed by AECL turnkey contract, started commercial operations in 1983. Units 2,3 and 4 were constructed by a non turn-key contract scheme, which was constructed by KHNP with assistance from AECL for some areas. The second part of the paper deals with the Romania-Korea cooperation status. The cooperation between Romania-Korea in the nuclear power field got into stride in March 2001. A technical agreement was signed between Romanian Company SNN and KHNP in March 2002 for cooperation in the Cernavoda projects. An amount of 32 tones of Romanian heavy water was supplied to KHNP, The Technical Assistance Agreement between SNN and KHNP stipulates provisions for technical services for operation of Unit 1, construction and commissioning of Cernavoda Unit 2. This Technical Assistance Agreement will be the basis to enhance economy and safety of Cernavoda Units 1,2 and 3. In the frame of the cooperation in Cernavoda Unit 3 Project Romania can enjoy benefits from Korea's world-top class technologies and experience. Korea can support Romania utilizing the systematically established nuclear infrastructure. Korea, both government and nuclear power industry represented by KHNP, will fully support Romania so that new feasibility study may proceed in accordance with the required schedule. The paper has the following structure: Part 1- Korean nuclear industry status: 1. Current status of electric power in Korea; 2. Long term energy plan; 3. Status of nuclear power projects; 4. Operational performance; 5. Outlines of Wolsong CANDU units; Part 2 - Romania-Korea cooperation status: 1. History for cooperation; 2. Technical assistance for Cernavoda Units 1 and 2; 3. Joint development of Cernavoda Unit 3 Project; 4. Cooperation in Cernavoda Unit 3 Project

  16. The effective crystal field potential

    CERN Document Server

    Mulak, J

    2000-01-01

    As it results from the very nature of things, the spherical symmetry of the surrounding of a site in a crystal lattice or an atom in a molecule can never occur. Therefore, the eigenfunctions and eigenvalues of any bound ion or atom have to differ from those of spherically symmetric respective free ions. In this way, the most simplified concept of the crystal field effect or ligand field effect in the case of individual molecules can be introduced. The conventional notion of the crystal field potential is narrowed to its non-spherical part only through ignoring the dominating spherical part which produces only a uniform energy shift of gravity centres of the free ion terms. It is well understood that the non-spherical part of the effective potential "seen" by open-shell electrons localized on a metal ion plays an essential role in most observed properties. Light adsorption, electron paramagnetic resonance, inelastic neutron scattering and basic characteristics derived from magnetic and thermal measurements, ar...

  17. Biological effects of electromagnetic fields

    International Nuclear Information System (INIS)

    Gabriel, C.

    1996-01-01

    The effects of electromagnetic (em) fields on biological systems were first observed and exploited well over a century ago. Concern over the possible health hazards of human exposure to such fields developed much later. It is now well known that excessive exposure to em fields may have in undesirable biological consequences. Standards were introduced to determine what constitute an excessive exposure and how to avoid it. Current concern over the issue of hazards stems mainly from recent epidemiological studies of exposed populations and also from the results of laboratory experiments in which whole animals are exposed in vivo or tissue and cell cultures exposed in vitro to low levels of irradiation. The underlying fear is the possibility of a causal relationship between chronic exposure to low field levels and some forms of cancer. So far the evidence does not add up to a firm statement on the matter. At present it is not known how and at what level, if at all, can these exposure be harmful to human health. This state of affair does not provide a basis for incorporating the outcome of such research in exposure standards. This paper will give a brief overview of the research in this field and how it is evaluated for the purpose of producing scientifically based standards. The emphasis will be on the physical, biophysical and biological mechanisms implicated in the interaction between em fields and biological systems. Understanding such mechanisms leads not only to a more accurate evaluation of their health implications but also to their optimal utilization, under controlled conditions, in biomedical applications. (author)

  18. Casimir effect for interacting fields

    International Nuclear Information System (INIS)

    Kay, B.S.

    1982-01-01

    The author discusses some recent work on the Casimir effect: that is the problem of renormalizing Tsub(μγ) on locally-flat space-times. That is on space-times which, while topologically non-trivial are locally Minkowskian - with vanishing local curvature. The author has developed a systematic method for calculating this Casimir effect for interacting fields to arbitrary order in perturbation theory - and for arbitrary components of Tsub(μγ) which he describes in general and then illustrates it by describing first order perturbation theory calculations for a lambdaphi 4 theory for the two models: the cylinder space-time and the parallel plates. (Auth.)

  19. Regulatory inspections in nuclear plants in the field of radiation protection

    International Nuclear Information System (INIS)

    Hort, M.; Fuchsova, D.

    2014-01-01

    State Office for Nuclear Safety executes state administration and performs inspections at peaceful use of nuclear energy and ionizing radiation in the field of radiation protection and nuclear safety. Inspections on radiation protection at nuclear power plants are secured by inspectors of the Department of Radiation Protection in Fuel Cycle, who work at the Regional centre Brno and Ceske Budejovice. (authors)

  20. Managing for nuclear operational effectiveness

    International Nuclear Information System (INIS)

    Nevins, P.A.; Kasperski, D.C.

    1990-01-01

    The nuclear energy industry worldwide is changing, with significant implications for nuclear utility managers. While the UK and US nuclear industries have many differences, a number of the lessons learned in the US have direct applicability to the UK. Just as the physics behind nuclear power transcends political boundaries, so do many of the management techniques that are necessary to run an efficient and sound operation. The US nuclear industry is no longer a construction-based industry, as it has been for years. As nuclear construction slows or stops in many parts of the world and nuclear power comes under increased scrutiny everywhere, the industry is shifting away from a construction emphasis and towards an operations and maintenance emphasis. In North America more than one-half of nuclear executives believe that plant operating and maintenance costs, and not construction-related problems, are their number one concern. Furthermore, when asked what actions they would expect to take as a result of this concern, the majority indicated that the actions would be management-related for the most part, and included items such as: emphasize operating improvements, emphasize management improvements, upgrade outage management and maintenance management programs, increase senior management involvement and set management performance criteria. (author)

  1. The Characteristics of an Effective Nuclear Regulator

    International Nuclear Information System (INIS)

    Cheok, Michael; Wertelaers, An; Lojk, Robert; Santini, Miguel; Alm-Lytz, Kirsi; Rigail, Anne-Cecile; Weidenbruck, Kai-Jochen; Stoppa, Gisela; Rainieri, Roberto; Aoki, Masahiro; Gonzalez-Mercado; Miroshnichenko, Mikhail; Kuznetsov, Nikolay; Kudryavtsev, Evgeny; Cid, Rafael; Franzen, Anna; Skanberg, Lars; Gibson, Steve; Golshan, Mina; Cheok, Michael; Nicic, Adriana; Salgado, Nancy; Creswell, Len

    2014-01-01

    Both national and international organisations agree that the fundamental objective of all nuclear safety regulatory bodies - the regulator's prime purpose - is to ensure that nuclear licensees operate their facilities at all times in a safe manner. Much has been written about ways to improve regulatory processes or to improve the effectiveness of a regulatory body, including in previous OECD/NEA regulatory guidance booklets. But until now, none have focused on the characteristics of an effective nuclear safety regulator. Effective organisations are those that have good leadership and are able to transform strategic direction into operational programmes. Effectiveness is about how well the organisation is achieving its fundamental purpose - in the case of a nuclear safety regulator, ensuring that licensees operate their facilities and discharge their obligations in a safe manner. This regulatory guidance booklet describes the characteristics of an effective nuclear safety regulator in terms of roles and responsibilities, principles and attributes. Each of the characteristics discussed in this report is a necessary feature of an effective nuclear safety regulator but no one characteristic is sufficient on its own. It is the combination of these characteristics that leads to the effectiveness of a nuclear regulatory body. The report provides a unique resource to countries with existing, mature regulators and can be used for benchmarking as well as training and developing staff. It will also be useful for new entrant countries in the process of developing and maintaining an effective nuclear safety regulator. (authors)

  2. The use of nuclear data in the field of nuclear fuel recycling

    Directory of Open Access Journals (Sweden)

    Martin Julie-Fiona

    2017-01-01

    Full Text Available AREVA NC La Hague facility is the first step of the nuclear fuel recycling process implemented in France. The processing of the used fuel is governed by high standards of criticality-safety, and strong expectations on the quality of end-products. From the received used fuel assemblies, the plutonium and the uranium are extracted for further energy production purposes within the years following the reprocessing. Furthermore, the ultimate waste – fission products and minor actinides on the one hand, and hulls and end-pieces on the other hand – is adequately packaged for long term disposal. The used fuel is therefore separated into very different materials, and time scales which come into account may be longer than in some other nuclear fields of activity. Given the variety of the handled nuclear materials, as well as the time scales at stake, the importance given to some radionuclides, and hence to the associated nuclear data, can also be specific to the AREVA NC La Hague plant. A study has thus been led to identify a list of the most important radionuclides for the AREVA NC La Hague plant applications, relying on the running constraints of the facility, and the end-products expectations. The activities at the AREVA NC La Hague plant are presented, and the methodology to extract the most important radionuclides for the reprocessing process is detailed.

  3. The use of nuclear data in the field of nuclear fuel recycling

    Science.gov (United States)

    Martin, Julie-Fiona; Launay, Agnès; Grassi, Gabriele; Binet, Christophe; Lelandais, Jacques; Lecampion, Erick

    2017-09-01

    AREVA NC La Hague facility is the first step of the nuclear fuel recycling process implemented in France. The processing of the used fuel is governed by high standards of criticality-safety, and strong expectations on the quality of end-products. From the received used fuel assemblies, the plutonium and the uranium are extracted for further energy production purposes within the years following the reprocessing. Furthermore, the ultimate waste - fission products and minor actinides on the one hand, and hulls and end-pieces on the other hand - is adequately packaged for long term disposal. The used fuel is therefore separated into very different materials, and time scales which come into account may be longer than in some other nuclear fields of activity. Given the variety of the handled nuclear materials, as well as the time scales at stake, the importance given to some radionuclides, and hence to the associated nuclear data, can also be specific to the AREVA NC La Hague plant. A study has thus been led to identify a list of the most important radionuclides for the AREVA NC La Hague plant applications, relying on the running constraints of the facility, and the end-products expectations. The activities at the AREVA NC La Hague plant are presented, and the methodology to extract the most important radionuclides for the reprocessing process is detailed.

  4. Numerical simulation of flow field in shellside of heat exchanger in nuclear power plant

    International Nuclear Information System (INIS)

    Wang Xinliang; Qiu Jinrong; Gong Zili

    2010-01-01

    Heat exchanger is the important equipment of nuclear power plant. Numerical simulation can give the detail information inside the heat exchange, and has been an effective research method. The geometric structure of shell-and-tube heat exchanger is very complex and it is difficult to simulate the whole flow field presently. According to the structure characteristics of the heat exchanger, a periodic whole-section calculation model was presented. The numerical simulation of flow field in shellside of heat exchange of a nuclear power plant was done by using this model. The results of simulation show that heat transfer in the periodic section of the heat exchange is uniform, the heat transfer is enhanced by using baffles in heat exchange, and frictional resistance is primary from the effect of segmental baffles. (authors)

  5. Cluster formation in nuclear reactions from mean-field inhomogeneities

    Science.gov (United States)

    Napolitani, Paolo; Colonna, Maria; Mancini-Terracciano, Carlo

    2018-05-01

    Perturbing fluids of neutrons and protons (nuclear matter) may lead, as the most catastrophic effect, to the rearrangement of the fluid into clusters of nucleons. A similar process may occur in a single atomic nucleus undergoing a violent perturbation, like in heavy-ion collisions tracked in particle accelerators at around 30 to 50 MeV per nucleon: in this conditions, after the initial collision shock, the nucleus expands and then clusterises into several smaller nuclear fragments. Microscopically, when violent perturbation are applied to nuclear matter, a process of clusterisation arises from the combination of several fluctuation modes of large-amplitude where neutrons and protons may oscillate in phase or out of phase. The imposed perturbation leads to conditions of instability, the wavelengths which are the most amplified have sizes comparable to small atomic nuclei. We found that these conditions, explored in heavy-ion collisions, correspond to the splitting of a nucleus into fragments ranging from Oxygen to Neon in a time interval shorter than one zeptosecond (10 ‑ 21s). From the out-of-phase oscillations of neutrons and protons another property arises, the smaller fragments belonging to a more volatile phase get more neutron enriched: in the heavy-ion collision case this process, called distillation, reflects in the isotopic distributions of the fragments. The resulting dynamical description of heavy-ion collisions is an improvement with respect to more usual statistical approaches, based on the equilibrium assumption. It allows in fact to characterise also the very fast early stages of the collision process which are out of equilibrium. Such dynamical description is the core of the Boltzmann-Langevin One Body (BLOB) model, which in its latest development unifies in a common approach the description of fluctuations in nuclear matter, and a predictive description of the disintegration of nuclei into nuclear fragments. After a theoretical introduction, a few

  6. Effective citizen advocacy of beneficial nuclear technologies

    International Nuclear Information System (INIS)

    McKibben, J. Malvyn; Wood, Susan

    2007-01-01

    In 1991, a small group of citizens from communities near the Savannah River Site (SRS) formed a pro-nuclear education and advocacy group, Citizens for Nuclear Technology Awareness (CNTA). Their purpose was to: (1) counter nuclear misinformation that dominated the nation's news outlets, (2) provide education on nuclear subjects to area citizens, students, elected officials, and (3) provide informed citizen support for potential new missions for SRS when needed. To effectively accomplish these objectives it is also essential to establish and maintain good relations with community leaders and reporters that cover energy and nuclear subjects. The organization has grown considerably since its inception and has expanded its sphere of influence. We believe that our experiences over these fifteen years are a good model for effectively communicating nuclear subjects with the public. This paper describes the structure, operation and some of the results of CNTA. (authors)

  7. Effects of electrospun chitosan wrapping for dry-ageing of beef, as studied by microbiological, physicochemical and low-field nuclear magnetic resonance analysis

    DEFF Research Database (Denmark)

    Guðjónsdóttir, María; Gacutan, Manuel D.; Mendes, Ana Carina Loureiro

    2015-01-01

    The effects of using electrospun chitosan fibres as a wrapping material for dry-ageing beef was studied and compared to traditional dry-ageing and wet-ageing of beef for up to 21 days. The chitosan treatment showed improved results in terms of yield, reduction of microbial counts, yeasts and moulds......, and lighter appearance compared to traditional dry-ageing. Weight and trimming losses were minimal in the wet-ageing beef. However, significant growth of lactic acid bacteria was observed in this group. Transverse relaxation times indicated a lower degree of muscle denaturation during ageing in the chitosan...... chitosan fibre mats have potential as a wrapping material for improved quality during dry-ageing of beef....

  8. High field nuclear magnetic resonance application to polysaccharide chemistry

    International Nuclear Information System (INIS)

    Vincendon, Marc

    1972-01-01

    Nuclear magnetic resonance has been applied to polysaccharide chemistry using time averaging technique and high fields (100 and 250 MHz). The three methyl signals of methyl cellulose and cellulose triacetate are separated, and the C-6 substituent has been identified. Biosynthesis of bacterial cellulose has been performed using deuterium labelled D-glucose and Acetobacter xylinum. Per-acetylated derivative of bacterial cellulose has been studied by NMR; this study permitted us to determine the quantity of deuterium on each position of the anhydro-glucose unit in the polymer. NMR has also been used to see the anomeric end chain of cellulose and amylose derivatives and to show the fixation of bromine and t-butyl group on the free anomeric end chain of cellulose triacetate. (author) [fr

  9. Application of the nuclear field theory to superfluid nuclei

    International Nuclear Information System (INIS)

    Reinhardt, H.

    1980-01-01

    The quasiparticle-phonon multiplet of superfluid spherical nuclei is investigated in the framework of the nuclear field theory (NFT), using the pairing plus quadrupole force. In leading order of the NFT expansion there exists a simple relation between the energy splitting of the multiplet and the ground state B(E lambda) transitions from the multiplet. This relation states that the reduced matrix elements for the B(E lambda) transition decrease linearly with increasing energies of the multiplet states. The extent to which this relation is fulfilled by available experimental data is checked. The influence of the spurious correlations involved in the NFT treatment due to the BCS approximation is estimated. The numerical calculations are performed for 93 Nb where the ground state B(E lambda) transitions are measured for all multiplet states. (orig.)

  10. Overview of the Italian activities in the field of life management of nuclear power plants

    International Nuclear Information System (INIS)

    Pini, A.

    1994-01-01

    Overview of the Italian activities in the field of life management of nuclear power plants is presented, including the following issues: nuclear energy scenario in Italy, study of reactor pressure vessel, piping and containment integrity, seismic risk analysis

  11. HOTSPOT, Field Evaluation of Radiation Release from Nuclear Accident

    International Nuclear Information System (INIS)

    2001-01-01

    1 - Description of program or function: The HOTSPOT Health Physics codes were created to provide Health Physics personnel with a fast, field-portable calculational tool for evaluating accidents involving radioactive materials. HOTSPOT codes are a first-order approximation of the radiation effects associated with the atmospheric release of radioactive materials. HOTSPOT programs are reasonably accurate for a timely initial assessment. More importantly, HOTSPOT codes produce a consistent output for the same input assumptions and minimize the probability of errors associated with reading a graph incorrectly or scaling a universal nomogram during an emergency. Four general programs, PLUME, EXPLOSION, FIRE, and RESUSPENSION, calculate a downwind assessment following the release of radioactive material resulting from a continuous or puff release, explosive release, fuel fire, or an area contamination event. Other programs deal with the release of plutonium, uranium, and tritium to expedite an initial assessment of accidents involving nuclear weapons. Additional programs estimate the dose commitment from inhalation of any one of the radionuclides listed in the database of radionuclides, calibrate a radiation survey instrument for ground survey measurements, and screening of plutonium uptake in the lung. The HOTSPOT codes are fast, portable, easy to use, and fully documented. HOTSPOT supports color high resolution monitors and printers for concentration plots and contours. The codes have been extensively used by the DOS community since 1985. Version 8 allows users to add their own custom radionuclide library and to create custom radionuclide mixtures. It also includes wet deposition to approximate the enhanced plume depletion and ground deposition due to the effects of rain. Additional release geometry options for TRITIUM RELEASE and GENERAL PLUME were added, as well as several other enhancements and improvements. See info (f1) from the main HOTSPOT menu for additional

  12. Fringing-field effects in acceleration columns

    International Nuclear Information System (INIS)

    Yavor, M.I.; Weick, H.; Wollnik, H.

    1999-01-01

    Fringing-field effects in acceleration columns are investigated, based on the fringing-field integral method. Transfer matrices at the effective boundaries of the acceleration column are obtained, as well as the general transfer matrix of the region separating two homogeneous electrostatic fields with different field strengths. The accuracy of the fringing-field integral method is investigated

  13. The greenhouse effect and nuclear energy

    International Nuclear Information System (INIS)

    Coulter, J.

    1988-01-01

    The author argues that nuclear power will do little to mitigate the problem of the greenhouse effect and is likely to exacerbate it. Changes since the mid 1970s illustrate the close linking of nuclear and economic growth with the associated growth of fossil fill consumption, the inability of nuclear power to substitute for fossil either technically or economically, and the greater contribution that can be made to energy availability and to reduction of carbon dioxide release by conservation

  14. Ambipolar phosphorene field effect transistor.

    Science.gov (United States)

    Das, Saptarshi; Demarteau, Marcel; Roelofs, Andreas

    2014-11-25

    In this article, we demonstrate enhanced electron and hole transport in few-layer phosphorene field effect transistors (FETs) using titanium as the source/drain contact electrode and 20 nm SiO2 as the back gate dielectric. The field effect mobility values were extracted to be ∼38 cm(2)/Vs for electrons and ∼172 cm(2)/Vs for the holes. On the basis of our experimental data, we also comprehensively discuss how the contact resistances arising due to the Schottky barriers at the source and the drain end effect the different regime of the device characteristics and ultimately limit the ON state performance. We also propose and implement a novel technique for extracting the transport gap as well as the Schottky barrier height at the metal-phosphorene contact interface from the ambipolar transfer characteristics of the phosphorene FETs. This robust technique is applicable to any ultrathin body semiconductor which demonstrates symmetric ambipolar conduction. Finally, we demonstrate a high gain, high noise margin, chemical doping free, and fully complementary logic inverter based on ambipolar phosphorene FETs.

  15. Laser induced nuclear orientation effects

    International Nuclear Information System (INIS)

    Burns, M.; Pappas, P.; Feld, M.S.; Murnick, D.E.

    1977-01-01

    Resonant laser radiation can orient metastable nuclei, resulting in spatially anisotropic emission of β or γ radiation. This technique can be used to obtain isomer shifts and nuclear moments and can lead to isomer separation. (Auth.)

  16. Principles and foundation: national standards on quantities and units in nuclear science field

    International Nuclear Information System (INIS)

    Chen Lishu

    1993-11-01

    The main contents of National Standards on Quantities and units of atomic and nuclear physics (GB 3102.9) and Quantities and Units of nuclear reactions and ionizing radiations (GB 310.10) are presented in which most important quantities with their symbols and definitions in the nuclear scientific field are given. The principles and foundation, including the International System of Units (SI) and its application to the nuclear scientific field, in the setting of the National Standards are explained

  17. Coordinated research project of the use of nuclear and related techniques in assessment of irrigation schedules of field crops to increase effective use of water in irrigation projects

    International Nuclear Information System (INIS)

    Anac, M.S.; Tuzel, I.H.; Anac, D.

    1995-01-01

    The study aimed at determining the followings; water consumptions. irrigation water requirements of new cotton variety N 84; specific growth stages of cotton which are less sensitive to stress so that the irrigation could be avoided without significant yield decrease; and interactions between deficit irrigation and nitrogen fertilizer use. The experiment was set up with 6 irrigation and three nitrogen fertilizer (0.60 , 120 kg.ha sup -1 ) treatments. The irrigation treatments employed single stress at vegetative, flowering and boll formation stages, in addition to full irrigation, continuous stress and the traditional practice. In stress conditions available soil water depleted to 75 - 80 %, whereas in normal irrigation the depletion was 40 % in 0.90 m. of root zone. In full irrigation treatment 8 irrigations were applied, whereas 3 or 4 irrigations were needed in continuous stress conditions. The number of irrigations were 6 or 7 for other stress treatments. Irrigation water applications varied form 424 to 751 mm. Seasonal ET were ranged between 659 and 899 mm. The highest monthly ET in august for all of the treatments. Daily ET were found to vary from 2.2 to 12.1 mm/day. The seed cotton yields, ky values and yield - N indices have indicated that the vegetative state was more sensitive to water stress. The stress at boll formation stage had slight effects on these parameters. Under limited water resource conditions, vegetative growth period of cotton should be given preference for irrigation, followed by flowering period. Omitting irrigation in boll formation period would result in 4.3 to 9.1 % water savings. Yield changes with respect to N rates showed that high N doses are accompanied by high yields. Nitrogen recoveries either from fertilizers or soil revealed high uptakes in full irrigation conditions. Nitrogen use efficiencies were also high in these conditions. Average of three years put forth that 19% of N in stress conditions and 29% in full irrigation were

  18. Field test of wireless sensor network in the nuclear environment

    International Nuclear Information System (INIS)

    Li, L.; Wang, Q.; Bari, A.; Deng, C.; Chen, D.; Jiang, J.; Alexander, Q.; Sur, B.

    2014-01-01

    Wireless sensor networks (WSNs) are appealing options for the health monitoring of nuclear power plants due to their low cost and flexibility. Before they can be used in highly regulated nuclear environments, their reliability in the nuclear environment and compatibility with existing devices have to be assessed. In situ electromagnetic interference tests, wireless signal propagation tests, and nuclear radiation hardness tests conducted on candidate WSN systems at AECL Chalk River Labs are presented. The results are favourable to WSN in nuclear applications. (author)

  19. Field test of wireless sensor network in the nuclear environment

    Energy Technology Data Exchange (ETDEWEB)

    Li, L., E-mail: lil@aecl.ca [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Wang, Q.; Bari, A. [Univ. of Western Ontario, London, Ontario (Canada); Deng, C.; Chen, D. [Univ. of Electronic Science and Technology of China, Chengdu, Sichuan (China); Jiang, J. [Univ. of Western Ontario, London, Ontario (Canada); Alexander, Q.; Sur, B. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    2014-06-15

    Wireless sensor networks (WSNs) are appealing options for the health monitoring of nuclear power plants due to their low cost and flexibility. Before they can be used in highly regulated nuclear environments, their reliability in the nuclear environment and compatibility with existing devices have to be assessed. In situ electromagnetic interference tests, wireless signal propagation tests, and nuclear radiation hardness tests conducted on candidate WSN systems at AECL Chalk River Labs are presented. The results are favourable to WSN in nuclear applications. (author)

  20. Progress on study of nuclear data theory and related fields at the Theory Group of CNDC

    Energy Technology Data Exchange (ETDEWEB)

    Zhigang, Ge [China Nuclear Data Center, CIAE (China)

    1996-06-01

    The Theory Group of CNDC (China Nuclear Data Center) has made a lot of progress in nuclear reaction theory and its application as well as many other related fields in 1995. The recent progress in nuclear reaction theory study and its applications, the recent progress in the nuclear data calculation and related code development are introduced. The production rate of radioactive nuclear beam induced by 70 MeV protons on {sup 72}Ge target were calculated. The calculated results are presented.

  1. Widespread after-effects of nuclear war

    International Nuclear Information System (INIS)

    Teller, E.

    1984-01-01

    Radioactive fallout and depletion of the ozone layer, once believed catastrophic consequences of nuclear war, are now proved unimportant in comparison to immediate war damage. Today, ''nuclear winter'' is claimed to have apocalyptic effects. Uncertainties in massive smoke production and in meteorological phenomena give reason to doubt this conclusion. (author)

  2. Health and environmental effects of nuclear weapons

    International Nuclear Information System (INIS)

    1995-08-01

    Since 1981 WHO has been studying and reporting on the effects of nuclear war on health and health services. This report provides information on the subject and refers to earlier related work of WHO. It forms the basis for a request from WHO to the International Court of Justice regarding the legality of the use of nuclear weapons. 15 refs

  3. Future of international cooperative activity for graduate school education in nuclear field

    International Nuclear Information System (INIS)

    Obara, Toru

    2008-01-01

    Further improvement of graduate school education in nuclear field is one of the important issues in universities in nuclear field. The COE-INES program has performed international cooperative activities for graduate school education with foreign universities in nuclear field. There are a lot of possibilities in international cooperation with foreign universities for graduate school education. The use of Internet can be a strong tool for the activities. (author)

  4. The environmental effects of nuclear war

    International Nuclear Information System (INIS)

    MacCracken, M.C.

    1988-09-01

    Substantial environmental disruption will significantly add to the disastrous consequences caused by the direct thermal, blast, and radiological effects brought on by a major nuclear war. Local fallout could cover several percent of the Northern Hemisphere with potentially lethal doses. Smoke from post-nuclear fires could darken the skies and induce temperature decreases of tens of degrees in continental interiors. Stratospheric ozone could be significantly reduced due to nitric oxide injections and smoke-induced circulation changes. The environmental effects spread the consequences of a nuclear war to the world population, adding to the potentially large disruptive effects a further reason to avoid such a catastrophe. 27 refs., 4 figs

  5. The Role of the Regulator in the Field of Safety Culture to Shun Nuclear Accident

    International Nuclear Information System (INIS)

    Kandil, M.M.

    2016-01-01

    The 2011 accident at the Fukushima Daiichi nuclear power plant in Japan has, as might be expected, led to improvements in equipment at plants around the world that have fortified safety systems and allowed for better protection against rare, extreme natural events. Equally important to the process of improving nuclear safety is the emphasis placed on implementing quality improvements to the human side of nuclear safety, a crucial element that is often not considered by those outside the nuclear sector. Ensuring nuclear reactor safety is not only a question of physical protection against all credible threats, enhancing robustness of important safety systems and increasing redundancy of back-up power and water cooling systems, but also one of making certain that qualified and trained staff are supported by effective procedures. However, these assets are valued only in an organizational culture that places a premium on ensuring high levels of safety, or implementing what is called an effectivenuclear safety culture”. Principles, characteristics and factors for effective safety culture are to great extent similar between licencees and regulatory bodies and can be applied for developing RB’s safety. Safety is the primary purpose of the regulatory body, Regulator plays a significant role in the field of nuclear safety even though the prime responsibility for safety belongs to the operator, and it is the regulator which actually decides what is considered to be safe. In order to effectively implement the international principle of high level of nuclear safety, nuclear safety culture should be clearly named as an objective in international nuclear legal acts and the regulator’s responsibility for promotion of nuclear safety culture should be established. What is more difficult for the regulator is finding the right balance of firmness but fairness in dealing with the operator. In addition to enforcing safety regulations, the regulator should have a positive

  6. Microscopic and Beyond-Mean-Field Constraints for a New Generation of Nuclear Energy Density Functionals

    International Nuclear Information System (INIS)

    Lesinski, Th.

    2008-09-01

    Nuclear structure is subject to a major renewal linked with the development of radioactive ion beams (such as the SPIRAL 1 and 2 beams at GANIL). Mean-field and density-functional methods are among the best suited for studying nuclei produced at such facilities. The present work aims at demonstrating how existing functionals can be improved so as to exhibit a better predictive power in little-explored regions of the nuclear chart. We propose a better description of the isospin-dependence of the effective interaction, and examine the relevance of adding a tensor coupling. We also show how a new generation of functionals can be better constrained by considering results obtained beyond the mean-field approximation. Finally, we attempt establishing a link with the bare nucleon-nucleon potential for the description of pairing, thus participating in the construction of a non-empirical functional. (author)

  7. The building of strategic information service in nuclear field facing to decision making

    International Nuclear Information System (INIS)

    Wang Yong; Xue Enjie; Yuan Huibin

    2010-01-01

    Objective: To study the structure of strategic information service system in nuclear field for decision making supporting. Methods: Investigating and studying the strategic information systems at different levels-domestic and overseas, regional and national, governmental and industrial as well as information departmental, putting forward the envisioning of strategic information service system in nuclear field. Results: The system is consisted of three parts: data part, data operating part using IT technology and service function part. The system can produce varied information outputs automatically based on rich information resources and IT technology under mathematical models. The information workers can analyze and study special strategic information needed based on this system. Conclusions: The envisioning for the system structure is feasible and it can be realized at present technology level. The service effect will be visible and the supporting to decision making will be weighty. (authors)

  8. Skyrme-Hartree-Fock in the realm of nuclear mean field models

    International Nuclear Information System (INIS)

    Reinhard, P.G.; Reiss, C.; Maruhn, J.; Bender, M.; Buervenich, T.; Greiner, W.

    2000-01-01

    We discuss and compare two brands of nuclear mean field models, the Skyrme-Hartree-Fock scheme (SHF) and the relativistic mean field model (RMF). Similarities and differences are worked out on a formal basis and with respect to the models performance in describing nuclear data. The bulk observables of stable nuclei are all described very well. Differences come up when extrapolating to exotic nuclei. The typically larger asymmetry energy in RMF leads to a larger neutron skin. Superheavy nuclei are found to be very sensitive on the single particle levels particularly on the spin orbit splitting. Ground state correlations from collective surface vibrations can have a significant effect on difference observables, as two-nucleon separation energy and two-nucleon shell gap. (author)

  9. Magnetic pseudo-fields in a rotating electron-nuclear spin system

    Science.gov (United States)

    Wood, A. A.; Lilette, E.; Fein, Y. Y.; Perunicic, V. S.; Hollenberg, L. C. L.; Scholten, R. E.; Martin, A. M.

    2017-11-01

    Analogous to the precession of a Foucault pendulum observed on the rotating Earth, a precessing spin observed in a rotating frame of reference appears frequency-shifted. This can be understood as arising from a magnetic pseudo-field in the rotating frame that nevertheless has physically significant consequences, such as the Barnett effect. To detect these pseudo-fields, a rotating-frame sensor is required. Here we use quantum sensors, nitrogen-vacancy (NV) centres, in a rapidly rotating diamond to detect pseudo-fields in the rotating frame. Whereas conventional magnetic fields induce precession at a rate proportional to the gyromagnetic ratio, rotation shifts the precession of all spins equally, and thus primarily affect 13C nuclear spins in the sample. We are thus able to explore these effects via quantum sensing in a rapidly rotating frame, and define a new approach to quantum control using rotationally induced nuclear spin-selective magnetic fields. This work provides an integral step towards realizing precision rotation sensing and quantum spin gyroscopes.

  10. Effect of nuclear education on public attitude

    International Nuclear Information System (INIS)

    Ohnishi, Teruaki

    1995-01-01

    A method is proposed to assess the effect of nuclear education. In this method, the nuclear education is treated as a part of the activities for public acceptance (PA), and a unit PA activity is assumed to give the same effect on the public, in essence, as a unit of nuclear information given by the newsmedia. Moreover, the change of attitude to nuclear energy is assumed to originate from enhanced understanding which, in turn, is brought by the stimulus given by the nuclear education. With the values of constants determined by using the data in Japan, example calculations were made for the educational time b 0 and the infiltration rate of education into minors B as parameters. It became clear from this calculation that the attitude to nuclear energy formed in the age of school children plays an essential role in shaping future public opinion since it is held in individuals without any notable modification for a long time after its formation, and that the effect of nuclear education to minors emerges depending on the variables b 0 and B in a highly non-linear manner. It was also found that there exists an optimum condition for nuclear education to attain the maximum amelioration of public opinion under a given condition of man-power for educational workers. (author)

  11. Electromagnetic field effects in explosives

    Science.gov (United States)

    Tasker, Douglas

    2009-06-01

    Present and previous research on the effects of electromagnetic fields on the initiation and detonation of explosives and the electromagnetic properties of explosives are reviewed. Among the topics related to detonating explosives are: measurements of conductivity; enhancement of performance; and control of initiation and growth of reaction. Hayes...()^1 showed a strong correlation of peak electrical conductivity with carbon content of the detonation products. Ershov.......^2 linked detailed electrical conductivity measurements with reaction kinetics and this work was extended to enhance detonation performance electrically;...^3 for this, electrical power densities of the order of 100 TW/m^2 of explosive surface normal to the detonation front were required. However, small electrical powers are required to affect the initiation and growth of reaction.......^4,5 A continuation of this work will be reported. LA-UR 09-00873 .^1 B. Hayes, Procs. of 4th Symposium (International) on Detonation (1965), p. 595. ^2 A. Ershov, P. Zubkov, and L. Luk'yanchikov, Combustion, Explosion, and Shock Waves 10, 776-782 (1974). ^3 M. Cowperthwaite, Procs. 9th Detonation Symposium (1989), p. 388-395. ^4 M. A. Cook and T. Z. Gwyther, ``Influence of Electric Fields on Shock to Detonation Transition,'' (1965). ^5 D. Salisbury, R. Winter, and L. Biddle, Procs. of the APS Topical Conference on Shock Compression of Condensed Matter (2005) p. 1010-1013.

  12. Nuclear effects in {sup 8}B dissociation

    Energy Technology Data Exchange (ETDEWEB)

    Kido, Toshihiko [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-07-01

    The break-up reaction of the nucleus on proton drip-line is investigated. A time-dependent Schroedinger equation for the relative motion between a weakly bound proton and core nucleus is numerically solved by treating the Coulomb+nuclear fields of a target as an external field. The theory is applied to the break-up reaction {sup 8}B + {sup 208}Pb {yields} {sup 7}Be + p + {sup 208}Pb. (author)

  13. Renormalons in effective field theories

    International Nuclear Information System (INIS)

    Luke, M.; Manohar, A.V.; Savage, M.J.

    1995-01-01

    We investigate the high-order behavior of perturbative matching conditions in effective field theories. These series are typically badly divergent, and are not Borel summable due to infrared and ultraviolet renormalons which introduce ambiguities in defining the sum of the series. We argue that, when treated consistently, there is no physical significance to these ambiguities. Although nonperturbative matrix elements and matching conditions are in general ambiguous, the ambiguity in any physical observable is always higher order in 1/M than the theory has been defined. We discuss the implications for the recently noticed infrared renormalon in the pole mass of a heavy quark. We show that a ratio of form factors in exclusive Λ b decays (which is related to the pole mass) is free from renormalon ambiguities regardless of the mass used as the expansion parameter of heavy quark effective theory. The renormalon ambiguities also cancel in inclusive heavy hadron decays. Finally, we demonstrate the cancellation of renormalons in a four-Fermi effective theory obtained by integrating out a heavy colored scalar

  14. Recent EU institutional developments in the nuclear field: outlook positive

    International Nuclear Information System (INIS)

    Ivens, Richard

    2008-01-01

    The main topics presented and discussed are:European Nuclear Energy Forum (ENEF); European Nuclear Installations Safety Standards (ENISS); High Level Group on Safety and Radioactive Waste (HLG); Sustainable Nuclear Energy Technology Platform (SNETP); Strategic Energy Technology Plan (SETP); EP report on Conventional Energies Forthcoming EU developments

  15. Atmospheric effects of a nuclear war

    International Nuclear Information System (INIS)

    Birks, J.W.

    1983-01-01

    The subject is discussed under the headings: nuclear war scenario (assumptions of size and place of explosions); fires; urban and forest fires; smoke and soot; darkness; meteorological and climatic effects; photochemical smog; ozone shield depletion; conclusions. (U.K.)

  16. Fields of progress: Nuclear techniques and food security

    International Nuclear Information System (INIS)

    Dargie, J.

    2000-01-01

    Isotopes and ionizing radiation have been used throughout the past half century to provide practical solutions to many issues and challenges facing the world's food and agricultural development. Since the mid-1960s, the IAEA and United Nations Food and Agriculture Organization (FAO) have worked together through the Joint FAO/IAEA Division, using their combined technical and managerial expertise and experience to bring the benefits of nuclear technology to farmers and consumers. This article reviews results of selected projects of the Joint FAO/IAEA Division that have contributed to food and agriculture. development. In some areas, it updates previous reports on the work of the Division and the FAO/IAEA Agriculture and Biotechnology Laboratory, which supports the Joint Programme. The article specifically focuses on three of the key strategic issues earmarked for intergovernmental attention at the World Food Summit and earlier at the UN Conference on Environment and Development in 1992. Each can be addressed effectively through nuclear technology that is supported by other technologies, national capacities, and an enabling political and economic environment

  17. The nuclear energy and the greenhouse effect

    International Nuclear Information System (INIS)

    Marignac, Y.; Legrand, V.

    2003-01-01

    This article tackles the problem of greenhouse effect and asks the question to know if the development of nuclear energy constitutes the answer to this problem. It appears that the nuclear energy cannot solve in itself the problem of greenhouse effect. Others actions on energy demand, on transport ( that is a big consumer of petroleum and that represents 25% of world emissions) have to studied and need a real policy will. (N.C.)

  18. Nuclear effects in neutrino oscillation experiments

    International Nuclear Information System (INIS)

    Chauhan, S.; Athar, M. Sajjad; Singh, S. K.

    2011-01-01

    We have studied the nuclear medium effects in the neutrino(antineutrino) induced interactions in nuclei which are relevant for present neutrino oscillation experiments in the few GeV energy region. The study is specially focused on calculating the cross sections and the event rates for atmospheric and accelerator neutrino experiments. The nuclear effects are found to be important for the quasielastic lepton production and the charged current incoherent and coherent pion production processes.

  19. Expectation to nuclear medicine in the field of respiratory diseases

    International Nuclear Information System (INIS)

    Nishimoto, Yukio; Kambe, Masayuki; Miyazawa, Teruomi

    1981-01-01

    This paper describes an expectation to the nuclear medicine for the early detection of pulmonary function abnormalities. The expectation includes: (1) To fill up the functional and qualitative diagnosis of respiratory diseases, (2) To improve the clinical nuclear laboratory tests by such methods like no effort and no risk for examinee, (3) To detect in the early stage of local pulmonary abnormalities, (4) To develop the clinical nuclear laboratory tests in order to measure some pulmonary functions at the same times and continuously, (5) To simplify the procedures in the clinical nuclear laboratory tests, and (6) To combine the clinical pulmonary function tests and clinical nuclear laboratory tests. (author)

  20. Development of training courses in the field of nuclear energy

    International Nuclear Information System (INIS)

    Lee, Han Young; Soe, In Seok; Lee, Ui Jin; Park, Jae Chang; Kim, Ik Hyeon; Won, Jong Yeol; Nam, Jae Yeol

    1993-12-01

    The nuclear training center provides various training courses in such areas of nuclear energy as nuclear power technology, radioisotope applications technology, non-destructive technology, nuclear safety, etc. The center also provides in-house staff training courses in project management, computer applications, and other research areas. The objective of the project is to develop new specialized training courses not only nuclear energy areas but also in management, so that localization of nuclear project can be accomplished as early as possible. The scope and contents of the project envision the following aims; 1. to develop specialized nuclear training programs; 2. to develop project management training courses for KAERI staff; 3. to collect and analyze foreign training programs and materials; 4. to develop foreign-assisted training courses; and 5. to develop international training courses for developing country trainese

  1. Nuclear energy and the greenhouse effect

    International Nuclear Information System (INIS)

    Weinberg, A.M.

    1990-01-01

    The extent and nature of the greenhouse effect are examined and placed in an environmental and historical context. The effect of energy policies on the greenhouse effect are discussed and the offending countries are identified. What energy policies would mitigate the greenhouse effect, and yet make good sense whether or not the effect proves to be real? Conservation is a desirable though not completely understood strategy. Conservation may not be a better bet in every instance than is increase in supply. If the greenhouse effect turns out to be real, nuclear energy can be one of the supply options that we turn to. If the greenhouse effect turns out to be false, and acceptable, economic nuclear option is surely better than one that does nothing but create strife and dissension. Let us remember that nuclear energy is the only large-scale non-fossil source other than hydropower that has been demonstrated to be practical. (author)

  2. Public involvement in decision making process in nuclear field

    International Nuclear Information System (INIS)

    Constantin, M.; Diaconu, D.

    2009-01-01

    Decision Making Process (DMP) in nuclear field is influenced by multiple factors such as: complex technical aspects, diversity of stakeholders, long term risks, psychological stresses, societal attitudes, etc. General public is sometimes considered as the only one of stakeholders, the involvement of the public being seen as a factor to obtain the acceptance in the late phase of DMP. Generally it is assessed by public consultation on the environment impact studies and by approval of the sitting through the local authorities decision. Modern society uses methods to involve public from the beginning of DMP. The paper shows a general view of the methods and tools used in Europe for public involvement in DMP. The process of construction of a continuous democratic dialog inside of Romanian Stakeholder Group (RSG) in the frame of the FP6-COWAM2 and CIP projects is presented with a focusing of the barriers and factors of disturbing the trust and collaboration between stakeholders. The influence on the public acceptance is also discussed. (authors)

  3. Isospin-dependent properties of asymmetric nuclear matter in relativistic mean-field models

    OpenAIRE

    Chen, Lie-Wen; Ko, Che Ming; Li, Bao-An

    2007-01-01

    Using various relativistic mean-field models, including the nonlinear ones with meson field self-interactions, those with density-dependent meson-nucleon couplings, and the point-coupling models without meson fields, we have studied the isospin-dependent bulk and single-particle properties of asymmetric nuclear matter. In particular, we have determined the density dependence of nuclear symmetry energy from these different relativistic mean-field models and compare the results with the constra...

  4. Stochastic Effects; Application in Nuclear Physics

    International Nuclear Information System (INIS)

    Mazonka, O.

    2000-04-01

    Stochastic effects in nuclear physics refer to the study of the dynamics of nuclear systems evolving under stochastic equations of motion. In this dissertation we restrict our attention to classical scattering models. We begin with introduction of the model of nuclear dynamics and deterministic equations of evolution. We apply a Langevin approach - an additional property of the model, which reflect the statistical nature of low energy nuclear behaviour. We than concentrate our attention on the problem of calculating tails of distribution functions, which actually is the problem of calculating probabilities of rare outcomes. Two general strategies are proposed. Result and discussion follow. Finally in the appendix we consider stochastic effects in nonequilibrium systems. A few exactly solvable models are presented. For one model we show explicitly that stochastic behaviour in a microscopic description can lead to ordered collective effects on the macroscopic scale. Two others are solved to confirm the predictions of the fluctuation theorem. (author)

  5. Pion propagator in relativistic quantum field theories of the nuclear many-body problem

    International Nuclear Information System (INIS)

    Matsui, T.; Serot, B.D.

    1982-01-01

    Pion interactions in the nuclear medium are studied using renormalizable relativistic quantum field theories. Previous studies using pseudoscalar πN coupling encountered difficulties due to the large strength of the πNN vertex. We therefore formulate renormalizable field theories with pseudovector πN coupling using techniques introduced by Weinberg and Schwinger. Calculations are performed for two specific models; the scalar-vector theory of Walecka, extended to include π and rho mesons in a non-chiral fashion, and the linear sigma-model with an additional neutral vector meson. Both models qualitatively reproduce low-energy πN phenomenology and lead to nuclear matter saturation in the relativistic Hartree formalism, which includes baryon vacuum fluctuations. The pions propagator is evaluated in the one-nucleon-loop approximation, which corresponds to a relativistic random-phase approximation built on the Hartree ground state. Virtual NN-bar loops are included, and suitable renormalization techniques are illustrated. The local-density approximation is used to compare the threshold pion self-energy to the s-wave pion-nucleus optical potential. In the non-chiral model, s-wave pion-nucleus scattering is too large in both pseudoscalar and pseudovector calculations, indicating that additional constraints must be imposed on the Lagrangian. In the chiral model, the threshold self-energy vanishes automatically in the pseudovector case, but does so for pseudoscalar coupling only if the baryon effective mass is chosen self-consistently Since extrapolation from free space to nuclear density can lead to large effects, pion propagation in the medium can determine which πN coupling is more suitable for the relativistic nuclear many-body problem. Conversely, pion interactions constrain the model Lagrangian and the nuclear matter equation of state. An approximately chiral model with pseudovector coupling is favored

  6. Nuclear Protection and Safety Institute R and D activities in the field of plant ageing

    Energy Technology Data Exchange (ETDEWEB)

    Deletre, G; Henry, J Y; Miannay, D; Olivera, J J; Horowitz, H; Barrachin, B

    1991-11-01

    A part of the work carried out by the CEA's Nuclear Protection and Safety Institute (IPSN) is devoted to revealing possible modifications in nuclear reactor materials under the combined effects of time, temperature and irradiation. The current R and D programme being carried out by the IPSN in collaboration with various specialized CEA departments concentrates on three main fields: - Reactor coolant system materials, - Polymerbased materials, - Coatings and paintings used inside pressurized water reactor containments. These activities are, of course, part of a much wider context which includes operating experience feedback, particularly as regards deterioration already observed in pressurized water reactors; this deterioration is usually the result of phenomena which were overlooked or inadequately studied at the design stage (corrosion, erosion, vibratory or thermal fatigue, cavitation, etc.). With his perspective in view, the IPSN is also undertaking a number of activities to develop powerful inspection methods and increase the effectiveness of preventive maintenance programmes.

  7. Nuclear Protection and Safety Institute R and D activities in the field of plant aging

    International Nuclear Information System (INIS)

    Deletre, G.; Henry, J.Y.; Miannay, D.; Olivera, J.J.; Horowitz, H.; Barrachin, B.

    1991-01-01

    A part of the work carried out by the CEA's Nuclear Protection and Safety Institute (IPSN) is devoted to revealing possible modifications in nuclear reactor materials under the combined effects of time, temperature and irradiation. The current R and D programme being carried out by the IPSN is collaboration with various specialized CEA departments concentrates on three main fields: Reactor coolant system materials, Polymerbased materials, Coatings and paintings used inside pressurized water reactor containments. These activities are, of course, part of a much wider context which includes operating experience feedback, particularly as regards deterioration already observed in pressurized water reactors; this deterioration is usually the result of phenomena which were overlooked or inadequately studied at the design stage (corrosion, erosion, vibratory or thermal fatigue, cavitation, etc). With this perspective in view, the IPSN is also undertaking a number of activities to develop powerful inspection methods and increase the effectiveness of preventive maintenance programmes. (author)

  8. Modeling quantization effects in field effect transistors

    International Nuclear Information System (INIS)

    Troger, C.

    2001-06-01

    Numerical simulation in the field of semiconductor device development advanced to a valuable, cost-effective and flexible facility. The most widely used simulators are based on classical models, as they need to satisfy time and memory constraints. To improve the performance of field effect transistors such as MOSFETs and HEMTs these devices are continuously scaled down in their dimensions. Consequently the characteristics of such devices are getting more and more determined by quantum mechanical effects arising from strong transversal fields in the channel. In this work an approach based on a two-dimensional electron gas is used to describe the confinement of the carriers. Quantization is considered in one direction only. For the derivation of a one-dimensional Schroedinger equation in the effective mass framework a non-parabolic correction for the energy dispersion due to Kane is included. For each subband a non-parabolic dispersion relation characterized by subband masses and subband non-parabolicity coefficients is introduced and the parameters are calculated via perturbation theory. The method described in this work has been implemented in a software tool that performs a self-consistent solution of Schroedinger- and Poisson-equation for a one-dimensional cut through a MOS structure or heterostructure. The calculation of the carrier densities is performed assuming Fermi-Dirac statistics. In the case of a MOS structure a metal or a polysilicon gate is considered and an arbitrary gate bulk voltage can be applied. This allows investigating quantum mechanical effects in capacity calculations, to compare the simulated data with measured CV curves and to evaluate the results obtained with a quantum mechanical correction for the classical electron density. The behavior of the defined subband parameters is compared to the value of the mass and the non-parabolicity coefficient from the model due to Kane. Finally the presented characterization of the subbands is applied

  9. Activities and cooperation in nuclear data field in China during 2000

    International Nuclear Information System (INIS)

    Zhuang Youxiang

    2001-01-01

    The paper includes follow contents: 1. meetings held in China in 2000, 2. the international meetings and workshops in nuclear data field attended by staffs of CNDC in 2000, 3. the foreign scientists in nuclear data field visited CNDC/CIAE in 2000, 4. staff of CNDC worked in or visited foreign country

  10. Radioactive and Other Effects of Nuclear Explosion

    International Nuclear Information System (INIS)

    Ilijas, B.; Cizmek, A.; Prah, M.; Medakovic, S.

    2008-01-01

    As a result of long lasting efforts of international community to definitely ban all test nuclear explosions, the Comprehensive Nuclear-Test-Ban Treaty (CTBT) was opened for signature in New York on 24 September 1996, when it was signed by 71 states, including Croatia. The State Office for Nuclear Safety (SONS) which, as an independent state regulatory authority has a responsibility for activities relating to nuclear safety, including the national authority over this Treaty, is actively engaged in CTBTO activities. The nuclear explosion causes a lot of effects (blast, thermal, radioactive, electromagnetic) which differs a lot in its nature, reach, lasting and other. The longest lasting aftermath is from the radioactive effects that cause a radioactive fallout and a lot of radioactive elements in the environment, created by the influence of a primary beam of radiation. Fission and fusion are the main source of radionuclide created by the nuclear explosion, and the longest lasting aftermaths are by the fission products, namely their offspring in natural disintegration chains. This can make contaminated areas inappropriate for life for very long periods. Even in the case of underground nuclear explosion (when underground cavity is formed with no effects on the surface), a leakage of radioactive gases through cracks is possible. A number of radionuclide is created by the neutron activation of elements naturally present in an environment, because a very strong neutron radiation appears in the moment of nuclear explosion. The abundance of particular radionuclide is a very much dependent of a place of performing nuclear explosion and a composition of soil or water in the vicinity.(author)

  11. Organic tunnel field effect transistors

    KAUST Repository

    Tietze, Max Lutz

    2017-06-29

    Various examples are provided for organic tunnel field effect transistors (OTFET), and methods thereof. In one example, an OTFET includes a first intrinsic layer (i-layer) of organic semiconductor material disposed over a gate insulating layer; source (or drain) contact stacks disposed on portions of the first i-layer; a second i-layer of organic semiconductor material disposed on the first i-layer surrounding the source (or drain) contact stacks; an n-doped organic semiconductor layer disposed on the second i-layer; and a drain (or source) contact layer disposed on the n-doped organic semiconductor layer. The source (or drain) contact stacks can include a p-doped injection layer, a source (or drain) contact layer, and a contact insulating layer. In another example, a method includes disposing a first i-layer over a gate insulating layer; forming source or drain contact stacks; and disposing a second i-layer, an n-doped organic semiconductor layer, and a drain or source contact.

  12. Nuclear collective vibrations in extended mean-field theory

    Energy Technology Data Exchange (ETDEWEB)

    Lacroix, D. [Lab. de Physique Corpusculaire/ ENSICAEN, 14 - Caen (France); Ayik, S. [Tennessee Technological Univ., Cookeville, TN (United States); Chomaz, Ph. [Grand Accelerateur National d' Ions Lourds (GANIL), 14 - Caen (France)

    2003-07-01

    The extended mean-field theory, which includes both the incoherent dissipation mechanism due to nucleon-nucleon collisions and the coherent dissipation mechanism due to coupling to low-lying surface vibrations, is briefly reviewed. Expressions of the strength functions for the collective excitations are presented in the small amplitude limit of this approach. This fully microscopic theory is applied by employing effective Skyrme forces to various giant resonance excitations at zero and finite temperature. The theory is able to describe the gross properties of giant resonance excitations, the fragmentation of the strength distributions as well as their fine structure. At finite temperature, the success and limitations of this extended mean-field description are discussed. (authors)

  13. Isospin effects on collective nuclear dynamics

    CERN Document Server

    Di Toro, M; Baran, V; Larionov, A B

    1999-01-01

    We suggest several ways to study properties of the symmetry term in the nuclear equation of state, EOS, from collective modes in beta-unstable nuclei. After a general discussion on compressibility and saturation density in asymmetric nuclear matter we show some predictions on the collective response based on the solution of generalized Landau dispersion relations. Isoscalar-isovector coupling, disappearance of collectivity and possibility of new instabilities in low and high density regions are discussed with accent on their relation to the symmetry term of effective forces. The onset of chemical plus mechanical instabilities in a dilute asymmetric nuclear matter is discussed with reference to new features in fragmentation reactions.

  14. Teaching concepts in the field of radioactivity and nuclear energy

    International Nuclear Information System (INIS)

    Bleichroth, W.

    1982-01-01

    This issue of 'Naturwissenschaften im Unterricht', dealing with the subjects of physics and chemistry, gives an account of the fundamentals of radioactivity, nuclear fission, controlled nuclear fission, nuclear power plants, dosimetry, safety engineering, shielding measures to prevent the release of radioactive substances, pressure engineering, emergency core cooling systems, waste disposal and natural and artificial environmental radioactivity. Teachers will find helpful hints as to the method of instruction and the explanation of problems. (DG) [de

  15. The Hungarian youth's knowledge and attitude in the nuclear field

    International Nuclear Information System (INIS)

    Petofi, G.; Legradi, G.

    2001-01-01

    The Young People for the Nuclear Energetics (FINE) was established in 1999 as the Hungarian branch of the Young Generation Network. Our purpose is to remove the misbelieves and fears arisen around the nuclear techniques and mainly the nuclear energetics and to reply the questions brought up by the Hungarian youth in this topic. In this year our main activity was to take part in the Student Island festival with a Nuclear-tent. In this paper our experience is delineated what we drawn with the help of our programmes about the attitude and the knowledge of the youth. (authors)

  16. Comments on thirty years' experience in the nuclear field

    International Nuclear Information System (INIS)

    Pecqueur, M.

    1983-01-01

    After having introduced the problem of the consumption of energy and its increasing demand, the author presents the development of nuclear energy in the industrial world, stressing the role played by each type of reactor in nuclear power development. The document presents also interesting features on the variation in time of PWH cost generated by nuclear reactors. In conclusion, the environmental impact as well as problems in relation with the nuclear controversy are underlined. The key role played by the IAEA in reactor safeguards is mentioned

  17. The Hungarian youth's knowledge and attitude in the nuclear field

    International Nuclear Information System (INIS)

    Petoefi, G.; Legradi, G.

    2000-01-01

    The Hungarian Youth for Nuclear (FINE) was established in 1999 as the Hungarian branch of the Young Generation Network. Our purpose is to remove the misconceptions and fears that have arisen around the nuclear techniques, mainly nuclear energetics, and to reply to the questions brought up by the Hungarian youth on this topic. This year, our main activity was to take part in the Student Island with a Nuclear-tent. In this paper we delineate our experience that we have gained with the help of our programmes about the attitude and knowledge of the Hungarian youth. (authors)

  18. Analysis of effect of safety classification on DCS design in nuclear power plants

    International Nuclear Information System (INIS)

    Gou Guokai; Li Guomin; Wang Qunfeng

    2011-01-01

    By analyzing the safety classification for the systems and functions of nuclear power plants based on the general design requirements for nuclear power plants, especially the requirement of availability and reliability of I and C systems, the characteristics of modem DCS technology and I and C products currently applied in nuclear power field are interpreted. According to the requirements on the safety operation of nuclear power plants and the regulations for safety audit, the effect of different safety classifications on DCS design in nuclear power plants is analyzed, by considering the actual design process of different DCS solutions in the nuclear power plants under construction. (authors)

  19. Nuclear beta decay induced by intense electromagnetic fields: Forbidden transition examples

    International Nuclear Information System (INIS)

    Reiss, H.R.

    1983-01-01

    A formalism developed earlier for the effect on nuclear beta decay of an intense plane-wave electromagnetic field is applied to three examples of forbidden beta transitions. The examples represent cases where the nuclear ''fragment'' contains one, two, and three nucleons; where the nuclear fragment is defined to be that smallest sub-unit of the nucleus containing the nucleon which undergoes beta decay plus any other nucleons directly angular-momentum coupled to it in initial or final states. The single-nucleon-fragment example is 113 Cd, which has a fourth-forbidden transition. The two-nucleon-fragment example is 90 Sr, which is first-forbidden. The three-nucleon-fragment example is 87 Rb, which is third-forbidden. An algebraic closed-form transition probability is found in each case. At low external-field intensity, the transition probability is proportional to z/sup L/, where z is the field intensity parameter and L is the degree of forbiddenness. At intermediate intensities, the transition probability behaves as z/sup L/-(1/2). At higher intensities, the transition probability contains the z/sup L/-(1/2) factor, a declining exponential factor, and an alternating polynomial in z. This high-intensity transition probability possesses a maximum value, which is found for each of the examples. A general rule, z = q 2 (2L-1), where q is the number of particles in the fragment, is found for giving an upper limit on the intensity at which the maximum transition probability occurs. Field-induced beta decay half-lives for all the examples are dramatically reduced from natural half-lives when evaluated at the optimum field intensity. Relative half-life reduction is greater the higher the degree of forbiddenness

  20. Symplectic dynamics of the nuclear mean-field

    International Nuclear Information System (INIS)

    Grigorescu, Marius

    1996-01-01

    Collective and microscopic pictures of the nuclear dynamics are related in the frame of time-dependent variational principle on symplectic trial manifolds. For symmetry braking systems such manifolds are constructed by cranking, and applied to study the nuclear isovector collective excitations. (author)

  1. The evolving role of governments in the nuclear energy field

    International Nuclear Information System (INIS)

    Anon.

    2004-01-01

    The NEA Nuclear Development Committee (NDC) recently completed a study that looks into the evolving role of governments in nuclear energy matters. Many decisions on government intervention in recent decades have been based on the earlier experience of what works best. The report suggests some considerations that all governments could take into account when establishing their respective roles. (author)

  2. The present status of international training and education in nuclear field held in Japan for Asian countries

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-11-01

    This report summarizes the training and educational courses for Asian countries carried out in Japan by the related institutions. The 2nd Workshop on Human Resources Development in the Nuclear Field was held on 27 and 28 of November 2000, based on FNCA (Forum for Nuclear Cooperation in Asia) organized by the Nuclear Energy Commission, and then the following day ''The Present Status of the International Training and Education in Japan for Asian Countries'' was reported for Asian participants on 29, November. This report is the Japanese edition of the handout distributed at the meeting. I believe it can be helpful for the related institutions in Japan to support the human resources development in the nuclear field efficiently and effectively in future. (author)

  3. Higgs effective field theories. Systematics and applications

    Energy Technology Data Exchange (ETDEWEB)

    Krause, Claudius G.

    2016-07-28

    Researchers of the Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) announced on July 4th, 2012, the observation of a new particle. The properties of the particle agree, within the relatively large experimental uncertainties, with the properties of the long-sought Higgs boson. Particle physicists around the globe are now wondering, ''Is it the Standard Model Higgs that we observe; or is it another particle with similar properties?'' We employ effective field theories (EFTs) for a general, model-independent description of the particle. We use a few, minimal assumptions - Standard Model (SM) particle content and a separation of scales to the new physics - which are supported by current experimental results. By construction, effective field theories describe a physical system only at a certain energy scale, in our case at the electroweak-scale v. Effects of new physics from a higher energy-scale, Λ, are described by modified interactions of the light particles. In this thesis, ''Higgs Effective Field Theories - Systematics and Applications'', we discuss effective field theories for the Higgs particle, which is not necessarily the Higgs of the Standard Model. In particular, we focus on a systematic and consistent expansion of the EFT. The systematics depends on the dynamics of the new physics. We distinguish two different consistent expansions. EFTs that describe decoupling new-physics effects and EFTs that describe non-decoupling new-physics effects. We briefly discuss the first case, the SM-EFT. The focus of this thesis, however, is on the non-decoupling EFTs. We argue that the loop expansion is the consistent expansion in the second case. We introduce the concept of chiral dimensions, equivalent to the loop expansion. Using the chiral dimensions, we expand the electroweak chiral Lagrangian up to next-to-leading order, O(f{sup 2}/Λ{sup 2})=O(1/16π{sup 2}). Further, we discuss how different

  4. Issues of effective field theories with resonances

    International Nuclear Information System (INIS)

    Gegelia, J.; Japaridze, G.

    2014-01-01

    We address some issues of renormalization and symmetries of effective field theories with unstable particles - resonances. We also calculate anomalous contributions in the divergence of the singlet axial current in an effective field theory of massive SU(N) Yang-Mills fields interacting with fermions and discuss their possible relevance to the strong CP problem. (author)

  5. Radiation Effects in Nuclear Waste Materials

    International Nuclear Information System (INIS)

    Weber, William J.

    2005-01-01

    The objective of this project is to develop a fundamental understanding of radiation effects in glasses and ceramics, as well as the influence of solid-state radiation effects on aqueous dissolution kinetics, which may impact the performance of nuclear waste forms and stabilized nuclear materials. This work provides the underpinning science to develop improved glass and ceramic waste forms for the immobilization and disposition of high-level tank waste, excess plutonium, plutonium residues and scrap, other actinides, and other nuclear waste streams. Furthermore, this work is developing develop predictive models for the performance of nuclear waste forms and stabilized nuclear materials. Thus, the research performed under this project has significant implications for the immobilization of High-Level Waste (HLW) and Nuclear Materials, two mission areas within the Office of Environmental Management (EM). With regard to the HLW mission, this research will lead to improved understanding of radiation-induced degradation mechanisms and their effects on dissolution kinetics, as well as development of predictive models for waste form performance. In the Nuclear Materials mission, this research will lead to improvements in the understanding of radiation effects on the chemical and structural properties of materials for the stabilization and long-term storage of plutonium, highly-enriched uranium, and other actinides. The research uses plutonium incorporation, ion-beam irradiation, and electron-beam irradiation to simulate the effects of alpha decay and beta decay on relevant glasses and ceramics. The research under this project has the potential to result in improved glass and ceramic materials for the stabilization and immobilization of high-level tank waste, plutonium residues and scraps, surplus weapons plutonium, highly-enriched uranium, other actinides, and other radioactive materials

  6. Radiation Effects in Nuclear Waste Materials

    International Nuclear Information System (INIS)

    Weber, William J.; Wang, Lumin; Hess, Nancy J.; Icenhower, Jonathan P.; Thevuthasan, Suntharampillai

    2003-01-01

    The objective of this project is to develop a fundamental understanding of radiation effects in glasses and ceramics, as well as the influence of solid-state radiation effects on aqueous dissolution kinetics, which may impact the performance of nuclear waste forms and stabilized nuclear materials. This work provides the underpinning science to develop improved glass and ceramic waste forms for the immobilization and disposition of high-level tank waste, excess plutonium, plutonium residues and scrap, other actinides, and other nuclear waste streams. Furthermore, this work is developing develop predictive models for the performance of nuclear waste forms and stabilized nuclear materials. Thus, the research performed under this project has significant implications for the immobilization of High-Level Waste (HLW) and Nuclear Materials, two mission areas within the Office of Environmental Management (EM). With regard to the HLW mission, this research will lead to improved understanding of radiation-induced degradation mechanisms and their effects on dissolution kinetics, as well as development of predictive models for waste form performance. In the Nuclear Materials mission, this research will lead to improvements in the understanding of radiation effects on the chemical and structural properties of materials for the stabilization and long-term storage of plutonium, highly-enriched uranium, and other actinides. The research uses plutonium incorporation, ion-beam irradiation, and electron-beam irradiation to simulate the effects of alpha decay and beta decay on relevant glasses and ceramics. The research under this project has the potential to result in improved glass and ceramic materials for the stabilization and immobilization of high-level tank waste, plutonium residues and scraps, surplus weapons plutonium, highly-enriched uranium, other actinides, and other radioactive materials

  7. Novel 1H low field nuclear magnetic resonance applications for the field of biodiesel

    Science.gov (United States)

    2013-01-01

    Background Biodiesel production has increased dramatically over the last decade, raising the need for new rapid and non-destructive analytical tools and technologies. 1H Low Field Nuclear Magnetic Resonance (LF-NMR) applications, which offer great potential to the field of biodiesel, have been developed by the Phyto Lipid Biotechnology Lab research team in the last few years. Results Supervised and un-supervised chemometric tools are suggested for screening new alternative biodiesel feedstocks according to oil content and viscosity. The tools allowed assignment into viscosity groups of biodiesel-petrodiesel samples whose viscosity is unknown, and uncovered biodiesel samples that have residues of unreacted acylglycerol and/or methanol, and poorly separated and cleaned glycerol and water. In the case of composite materials, relaxation time distribution, and cross-correlation methods were successfully applied to differentiate components. Continuous distributed methods were also applied to calculate the yield of the transesterification reaction, and thus monitor the progress of the common and in-situ transesterification reactions, offering a tool for optimization of reaction parameters. Conclusions Comprehensive applied tools are detailed for the characterization of new alternative biodiesel resources in their whole conformation, monitoring of the biodiesel transesterification reaction, and quality evaluation of the final product, using a non-invasive and non-destructive technology that is new to the biodiesel research area. A new integrated computational-experimental approach for analysis of 1H LF-NMR relaxometry data is also presented, suggesting improved solution stability and peak resolution. PMID:23590829

  8. An Effective Method For Nuclear Technology Transfer

    International Nuclear Information System (INIS)

    Jeon, Jan Pung

    1987-01-01

    Three basic entities involved in the implementation of nuclear projects are the Owner, Regulatory Authority and Nuclear Industry. Their ultimate objective is to secure the safe, reliable and economical nuclear energy. For s successful nuclear power program, the owner should maintain a good relationship with the other entities and pursue an optimization of the objectives. On the other hand, he should manage projects along the well - planned paths in order to effectively learn the nuclear technology. One of the problems in the nuclear projects of developing countries was the absence of long - term technology development program, a limited local participation and the technical incapability. For the effective technology transfer, a motivation of the technology supplier and a readiness of the recipient to accommodate such technologies are required. Advanced technology is usually developed at considerable expense with the expectation that the developer will use it in furthering his own business. Therefore, he tends to be reluctant to transfer it to the others, particularly, to the potential competitors. There is a disinclination against further technology transfer beyond the minimum contractual obligation or the requirements by Government Regulatory. So, an additional commercial incentive must be provided to the developer

  9. Deregulation and Nuclear Training: Cost Effective Alternatives

    International Nuclear Information System (INIS)

    Richard P. Coe; Patricia A. Lake

    2000-01-01

    Training is crucial to the success of any organization. It is also expensive, with some estimates exceeding $50 billion annually spent on training by U.S. corporations. Nuclear training, like that of many other highly technical organizations, is both crucial and costly. It is unlikely that the amount of training can be significantly reduced. If anything, current trends indicate that training needs will probably increase as the industry and workforce ages and changes. With the advent of energy deregulation in the United States, greater pressures will surface to make the costs of energy more cost-competitive. This in turn will drive businesses to more closely examine existing costs and find ways to do things in a more cost-effective way. The commercial nuclear industry will be no exception, and nuclear training will be equally affected. It is time for nuclear training and indeed the entire nuclear industry to begin using more aggressive techniques to reduce costs. This includes the need for nuclear training to find alternatives to traditional methods for the delivery of cost-effective high-quality training that meets regulatory requirements and produces well-qualified personnel capable of working in an efficient and safe manner. Computer-based and/or Web-based training are leading emerging technologies

  10. Shell effects in the nuclear deformation energy

    International Nuclear Information System (INIS)

    Ross, C.K.

    1973-01-01

    A new approach to shell effects in the Strutinsky method for calculating nuclear deformation energy is evaluated and the suggestion of non-conservation of angular momentum in the same method is resolved. Shell effects on the deformation energy in rotational bands of deformed nuclei are discussed. (B.F.G.)

  11. Numerical study of the THM effects on the near-field safety of a hypothetical nuclear waste repository - BMT1 of the DECOVALEX III project. Part 1: conceptualization and characterization of the problems and summary of results

    International Nuclear Information System (INIS)

    Chijimatsu, M.; Nguyen, T.S.; Jing, L.; De Jonge, J.; Kohlmeier, M.; Millard, A.; Rejeb, A.; Rutqvist, J.; Souley, M.; Sugita, Y.

    2004-01-01

    Geological disposal of the spent nuclear fuel uses often the concept of multiple barrier systems. In order to predict the performance of these barriers, mathematical models have been developed, verified and validated against analytical solutions, laboratory tests and field experiments within the international DECOVALEX III project. These models in general consider the full coupling of thermal (T), hydraulic (H) and mechanical (M) processes that would prevail in the geological media around the repository. For Bench Mark Test no. 1 (BMT1) of the DECOVALEX III project, seven multinational research teams studied the implications of coupled THM processes on the safety of a hypothetical nuclear waste repository at the near-field and are presented in three accompany papers in this issue. This paper is the first of the three companion papers, which provides the conceptualization and characterization of the BMT1 as well as some general conclusions based on the findings of the numerical studies. It also shows the process of building confidence in the mathematical models by calibration with a reference T-H-M experiment with realistic rock mass conditions and bentonite properties and measured outputs of thermal, hydraulic and mechanical variables

  12. Studies of Health Effects from Nuclear Testing near the Semipalatinsk Nuclear Test Site, Kazakhstan

    Directory of Open Access Journals (Sweden)

    Bernd Grosche

    2015-05-01

    Full Text Available The nuclear bomb testing conducted at the Semipalatinsk nuclear test site in Kazakhstan is of great importance for today’s radiation protection research, particularly in the area of low dose exposures. This type of radiation is of particular interest due to the lack of research in this field and how it impacts population health. In order to understand the possible health effects of nuclear bomb testing, it is important to determine what studies have been conducted on the effects of low dose exposure and dosimetry, and evaluate new epidemiologic data and biological material collected from populations living in proximity to the test site. With time, new epidemiological data has been made available, and it is possible that these data may be linked to biological samples. Next to linking existing and newly available data to examine health effects, the existing dosimetry system needs to be expanded and further developed to include residential areas, which have not yet been taken into account. The aim of this paper is to provide an overview of previous studies evaluating the health effects of nuclear testing, including some information on dosimetry efforts, and pointing out directions for future epidemiologic studies.

  13. Studies of Health Effects from Nuclear Testing near the Semipalatinsk Nuclear Test Site, Kazakhstan.

    Science.gov (United States)

    Grosche, Bernd; Zhunussova, Tamara; Apsalikov, Kazbek; Kesminiene, Ausrele

    2015-01-01

    The nuclear bomb testing conducted at the Semipalatinsk nuclear test site in Kazakhstan is of great importance for today's radiation protection research, particularly in the area of low dose exposures. This type of radiation is of particular interest due to the lack of research in this field and how it impacts population health. In order to understand the possible health effects of nuclear bomb testing, it is important to determine what studies have been conducted on the effects of low dose exposure and dosimetry, and evaluate new epidemiologic data and biological material collected from populations living in proximity to the test site. With time, new epidemiological data has been made available, and it is possible that these data may be linked to biological samples. Next to linking existing and newly available data to examine health effects, the existing dosimetry system needs to be expanded and further developed to include residential areas, which have not yet been taken into account. The aim of this paper is to provide an overview of previous studies evaluating the health effects of nuclear testing, including some information on dosimetry efforts, and pointing out directions for future epidemiologic studies.

  14. Resonant cell of a double nuclear electron resonance spectrometer for performance in a 120-350 Gs magnetic field

    International Nuclear Information System (INIS)

    Baldin, V.I.; Stepanov, A.P.

    1976-01-01

    Spectrometer double-frequency resonance cell construction of a double nuclear electron resonance for operation in 120-350 Gs magnetic fields is described. The cell has been developed from a special decimeter resonator with a concentrated capacitance. The electric and magnetic components of a high frequency field are efficiently divided in the separator. Therefore, the insertion of a measuring coil and a sample in the maximum of the magnetic component of the field does not practically affect the distribution and parameters of the high-frequency field. The double-frequency resonance cell proposed provides for a higher accuracy of measuring amplifications of the nuclear magnetic resonance signals when there is the overhauzer effect for 120-350 Gs magnetic fields

  15. Pauli Spin Blockade and the Ultrasmall Magnetic Field Effect

    KAUST Repository

    Danon, Jeroen

    2013-08-06

    Based on the spin-blockade model for organic magnetoresistance, we present an analytic expression for the polaron-bipolaron transition rate, taking into account the effective nuclear fields on the two sites. We reveal the physics behind the qualitatively different magnetoconductance line shapes observed in experiment, as well as the ultrasmall magnetic field effect (USFE). Since our findings agree in detail with recent experiments, they also indirectly provide support for the spin-blockade interpretation of organic magnetoresistance. In addition, we predict the existence of a similar USFE in semiconductor double quantum dots tuned to the spin-blockade regime.

  16. Pauli Spin Blockade and the Ultrasmall Magnetic Field Effect

    KAUST Repository

    Danon, Jeroen; Wang, Xuhui; Manchon, Aurelien

    2013-01-01

    Based on the spin-blockade model for organic magnetoresistance, we present an analytic expression for the polaron-bipolaron transition rate, taking into account the effective nuclear fields on the two sites. We reveal the physics behind the qualitatively different magnetoconductance line shapes observed in experiment, as well as the ultrasmall magnetic field effect (USFE). Since our findings agree in detail with recent experiments, they also indirectly provide support for the spin-blockade interpretation of organic magnetoresistance. In addition, we predict the existence of a similar USFE in semiconductor double quantum dots tuned to the spin-blockade regime.

  17. Stern-Gerlach effect without magnetic-field gradient

    International Nuclear Information System (INIS)

    Zimmer, O.; Felber, J.; Schaerpf, O.

    2001-01-01

    The Stern-Gerlach effect is the well-known spin-dependent splitting of a neutral particle beam by a magnetic-field gradient. Guided by the pseudomagnetic analogy, we performed a similar experiment where no magnetic-field gradient is involved. The effect is due to the spin-dependence of neutron scattering from polarised nuclei, i.e. caused by the strong interaction between neutrons and nuclei. The beam splitting is proportional to the nuclear polarisation and to the spin-dependent part of the neutron scattering length. Thus it can be used to measure one of both quantities. (orig.)

  18. Branch file of nonconventional literature in nuclear fields

    International Nuclear Information System (INIS)

    Kohoutova, J.

    The INIS system is completed with a system used by the Nuclear Information Centre for processing all Czecoslovak nonconventional literature on nuclear science and technology, including research reports, searches, translations, trip reports, theses, and information on scientific and technical events in Czechoslovakia, ie., documents that are not normally inputted in INIS. Bibliographies are published in a secondary periodical which is only circulated in Czechoslovakia. The possibilities and prerequisited of automating this work are analyzed. (Ha)

  19. Covariance methods and practices in the field of nuclear data

    International Nuclear Information System (INIS)

    Piksaikin, V.

    1988-01-01

    This document contains the 14 invited papers presented at the quoted meeting and summarizes the conclusions and recommendations that arose from the discussions during this meeting. Special emphasis was given to the treatment of correlated neutron nuclear data in fission and fusion reactor applications including computations related to neutron dosimetry and neutron spectra, fission-product yield data, and evaluated nuclear data files. (author). Refs, figs and tabs

  20. Quantum field theory and symmetries in nuclear physics

    International Nuclear Information System (INIS)

    Baldin, A.M.

    2000-01-01

    Nuclear physics embraces a wide area of knowledge ranging from fundamental problems of matter structure up to the origin of the universe. Applied aspects of this science bear a direct relation to the most urgent problems of people's life - ecology and energetics. The present talk deals with one of these aspects, namely, a possible description of the properties of nuclear matter by means of the methods of modern mathematical physics which N.N. Bogolyubov has greatly contributed to

  1. The climatic effects of nuclear war

    Science.gov (United States)

    Turco, R. P.; Toon, O. B.; Ackerman, T. P.; Pollack, J. B.; Sagan, C.

    1984-01-01

    The effects of various US-USSR nuclear-exchange scenarios on global climate are investigated by means of computer simulations, summarizing the results of Turco et al. (1983) and follow-up studies using 3D global-circulation models. A nuclear-scenario model is used to determine the amounts of dust, smoke, radioactivity, and pyrotoxins generated by a particular type of nuclear exchange (such as a general 5,000-Mt exchange, a 1,000-Mt limited exchange, a 5,000-Mt hard-target counterforce attack, and a 100-Mt attack on cities only): a particle-microphysics model predicts the evolution of the dust and smoke particles; and a radiative-convective climate model estimates the effects of the dust and smoke clouds on the global radiation budget. The findings are presented in graphs, diagrams, and a table. Thick clouds blocking most sunlight over the Northern Hemisphere midlatitudes for weeks or months and producing ground-temperature reductions of 20-40 C, disruption of global circulation patterns, and rapid spread of clouds to the Southern Hemisphere are among the 'nuclear-winter' effects predicted for the 5,000-Mt baseline case. The catastrophic consequences for plant, animal, and human populations are considered, and the revision of superpower nuclear strategies is urged.

  2. Biological effects of nuclear radiation

    International Nuclear Information System (INIS)

    Hotz, G.

    1975-01-01

    After a brief survey about the main radiobiological effects caused by ionizing radiation, human symptoms after irradiation and incorporation are shown. The special radiotoxic effect of radionuclides which are chemically associated with metabolism-specific elements such as calcium and potassium is shown and methods of treatment are indicated. (ORU) [de

  3. Realistic effective interactions for nuclear systems

    International Nuclear Information System (INIS)

    Hjort-Jensen, M.; Osnes, E.; Kuo, T.T.S.

    1994-09-01

    A review of perturbative many-body descriptions of several nuclear systems is presented. Symmetric and asymmetric nuclear matter and finite nuclei with few valence particles are examples of systems considered. The many-body description starts with the most recent meson-exchange potential models for the nucleon-nucleon interaction, an interaction which in turn is used in perturbative schemes to evaluate the effective interaction for finite nuclei and infinite nuclear matter. A unified perturbative approach based on time-dependent perturbation theory is elaborated. For finite nuclei new results are presented for the effective interaction and the energy spectra in the mass areas of oxygen, calcium and tin. 166 refs., 83 refs., 21 tabs

  4. Effective theories of single field inflation when heavy fields matter

    CERN Document Server

    Achucarro, Ana; Hardeman, Sjoerd; Palma, Gonzalo A; Patil, Subodh P

    2012-01-01

    We compute the low energy effective field theory (EFT) expansion for single-field inflationary models that descend from a parent theory containing multiple other scalar fields. By assuming that all other degrees of freedom in the parent theory are sufficiently massive relative to the inflaton, it is possible to derive an EFT valid to arbitrary order in perturbations, provided certain generalized adiabaticity conditions are respected. These conditions permit a consistent low energy EFT description even when the inflaton deviates off its adiabatic minimum along its slowly rolling trajectory. By generalizing the formalism that identifies the adiabatic mode with the Goldstone boson of this spontaneously broken time translational symmetry prior to the integration of the heavy fields, we show that this invariance of the parent theory dictates the entire non-perturbative structure of the descendent EFT. The couplings of this theory can be written entirely in terms of the reduced speed of sound of adiabatic perturbat...

  5. Consequences of the center-of-mass correction in nuclear mean-field models

    International Nuclear Information System (INIS)

    Bender, M.; Rutz, K.; Reinhard, P.G.; Maruhn, J.A.

    2000-01-01

    We study the influence of the scheme for the correction for spurious center-of-mass motion on the fit of effective interactions for self-consistent nuclear mean-field calculations. We find that interactions with very simple center-of-mass correction have significantly larger surface coefficients than interactions for which the center-of-mass correction was calculated for the actual many-body state during the fit. The reason for that is that the effective interaction has to counteract the wrong trends with nucleon number of all simplified schemes for center-of-mass correction which puts a wrong trend with mass number into the effective interaction itself. The effect becomes clearly visible when looking at the deformation energy of largely deformed systems, e.g. superdeformed states or fission barriers of heavy nuclei. (orig.)

  6. Effective field theory description of halo nuclei

    Science.gov (United States)

    Hammer, H.-W.; Ji, C.; Phillips, D. R.

    2017-10-01

    Nuclear halos emerge as new degrees of freedom near the neutron and proton driplines. They consist of a core and one or a few nucleons which spend most of their time in the classically-forbidden region outside the range of the interaction. Individual nucleons inside the core are thus unresolved in the halo configuration, and the low-energy effective interactions are short-range forces between the core and the valence nucleons. Similar phenomena occur in clusters of 4He atoms, cold atomic gases near a Feshbach resonance, and some exotic hadrons. In these weakly-bound quantum systems universal scaling laws for s-wave binding emerge that are independent of the details of the interaction. Effective field theory (EFT) exposes these correlations and permits the calculation of non-universal corrections to them due to short-distance effects, as well as the extension of these ideas to systems involving the Coulomb interaction and/or binding in higher angular-momentum channels. Halo nuclei exhibit all these features. Halo EFT, the EFT for halo nuclei, has been used to compute the properties of single-neutron, two-neutron, and single-proton halos of s-wave and p-wave type. This review summarizes these results for halo binding energies, radii, Coulomb dissociation, and radiative capture, as well as the connection of these properties to scattering parameters, thereby elucidating the universal correlations between all these observables. We also discuss how Halo EFT's encoding of the long-distance physics of halo nuclei can be used to check and extend ab initio calculations that include detailed modeling of their short-distance dynamics.

  7. Engineering effects of underground nuclear explosions

    Energy Technology Data Exchange (ETDEWEB)

    Boardman, Charles R [CER Geonuclear Corporation, Las Vegas, NV (United States)

    1970-05-01

    Useful effects of contained underground nuclear explosions are discussed in light of today's most promising potential applications. Relevant data obtained through exploration of explosion environments of nine U.S. tests in competent rock are summarized and presented as a practical basis for estimating magnitudes of effects. Effects discussed include chimney configuration, permeability, and volume as well as rubble particle size distributions and extents of permeability change in the chimney wall rock. Explosion mediums include shale, granite, dolomite, and salt. (author)

  8. Animal Effects from Soviet Atmospheric Nuclear Tests

    Science.gov (United States)

    2008-03-01

    describes the effect on animal models of atmospheric nuclear weapons tests performed by the Soviet Union at the Semipalatinsk Test Site . Part I describes...understand the pathogenic mechanisms of injury and the likelihood of efficacy of proposed treatment measures. 15. SUBJECT TERMS Semipalatinsk Test Site ...the Semipalatinsk Test Site . Part 1 describes the air blast and thermal radiation effects. Part 2 covers the effects of primary (prompt) radiation and

  9. Engineering effects of underground nuclear explosions

    International Nuclear Information System (INIS)

    Boardman, Charles R.

    1970-01-01

    Useful effects of contained underground nuclear explosions are discussed in light of today's most promising potential applications. Relevant data obtained through exploration of explosion environments of nine U.S. tests in competent rock are summarized and presented as a practical basis for estimating magnitudes of effects. Effects discussed include chimney configuration, permeability, and volume as well as rubble particle size distributions and extents of permeability change in the chimney wall rock. Explosion mediums include shale, granite, dolomite, and salt. (author)

  10. Genetic effects of nonionizing electromagnetic fields

    International Nuclear Information System (INIS)

    Lai, Henry

    2001-01-01

    Due to the increased use of electricity and wireless communication devices, there is a concern on whether exposure to nonionizing electromagnetic fields (50/60 Hz fields and radiofrequency radiation) can lead to harmful health effects, particularly, genetic effects and cancer development. This presentation will review recent research on genetic effects of power line frequency and radiofrequency electromagnetic fields. Even though the mechanism of interaction is still unknown, there is increasing evidence that these electromagnetic fields at low intensities can cause genetic damage in cells. There is also evidence suggesting that the effects are caused by oxidative stress. (author)

  11. International Cooperation of the Republic of Croatia in the Field of Radiological and Nuclear Safety

    International Nuclear Information System (INIS)

    Novosel, N.

    2011-01-01

    International cooperation of the Republic of Croatia in the field of radiological and nuclear safety can be divided in two parts - political part, for which the Ministry of Foreign Affairs and European Integration is responsible, and technical part, for which the State Office for Radiological and Nuclear Safety is responsible. According to the Radiological and Nuclear Safety Act (OG 28/10) the State Office for Radiological and Nuclear Safety: ''coordinates technical cooperation with the International Atomic Energy Agency for all participants from the Republic of Croatia''; ''fulfils the obligations which the Republic of Croatia has assumed through international conventions and bilateral agreements concerning protection against ionising radiation, nuclear safety and the application of protective measures aimed at the non-proliferation of nuclear weapons'' and ''cooperates with international and domestic organisations and associations in the area of protection against ionising radiation and nuclear safety, and appoints its own expert representatives to take part in the work of such organisations and associations or to monitor their work''. In this paper various aspects of the technical cooperation with the International Atomic Energy Agency, as well as international conventions and bilateral agreements in the field of radiological and nuclear safety, are presented. Also, cooperation with other international organizations and associations in the area of radiological and nuclear safety, such as Nuclear Suppliers Group, the Zangger Committee, the Wassenaar Arrangement, Comprehensive Nuclear-Test-Ban Treaty Organization, Euratom and certain civil expert groups of NATO, is described. (author)

  12. International Cooperation of the Republic of Croatia in the Field of Nuclear Safety

    International Nuclear Information System (INIS)

    Novosel, N.; Rosandic, L.

    2010-01-01

    International cooperation of the Republic of Croatia in the field of nuclear safety can be divided in two parts - political part, for which the Ministry of Foreign Affairs and European Integration is responsible, and technical part, for which the State Office for Nuclear Safety is responsible, in cooperation with other state administration bodies, where applicable. According to the Nuclear Safety Act (OG 73/2003) the State Office for Nuclear Safety: 'coordinates technical cooperation with the International Atomic Energy Agency for all participants from the Republic of Croatia'; 'fulfills the obligations which the Republic of Croatia has assumed through international conventions and bilateral agreements concerning nuclear safety and the application of protective measures aimed at the non-proliferation of nuclear weapons' and 'cooperates with international organizations and associations in the area of nuclear safety, and appoints its own expert representatives to take part in the work of such organizations and associations or to monitor their work'. In this paper various aspects of the technical cooperation with the International Atomic Energy Agency, as well as international conventions and bilateral agreements in the field of nuclear safety, will be presented. Also, cooperation with other international organizations and associations in the nuclear area, such as Nuclear Suppliers Group, Zangger Committee, Wassenaar Arrangement, Comprehensive Nuclear-Test-Ban Treaty Organization, Euratom and certain civil expert groups of NATO, will be described.(author).

  13. Effective Methods of Nuclear Power Technology Transfer

    International Nuclear Information System (INIS)

    Shave, D. F.; Kent, G. F.; Giambusso, A.

    1987-01-01

    An effective technology transfer program is a necessary and significant step towards independence in nuclear power technology. Attaining success in the conduct of such a program is a result of a) the donor and recipient jointly understanding the fundamental concepts of the learning process, b) sharing a mutual philosophy involving a partnership relationship, c) joint and careful planning, d) rigorous adherence to proven project management techniques, and e) presence of adequate feedback to assure continuing success as the program proceeds. Several years ago, KEPCO President Park, Jung-KI presented a paper on technology in which he stated, 'Nuclear technology is an integration of many unit disciplines, and thus requires extensive investment and training in order to establish the base for efficient absorption of transferred technology.' This paper addresses President Park's observations by discussing the philosophy, approach, and mechanisms that are necessary to support an efficient and effective process of nuclear power technology transfer. All technical content and presentation methods discussed are based on a technology transfer program developed by Stone and Webster, as an Engineer/Constructor for nuclear power plants, and are designed and implemented to promote the primary program goal - the ability of the trainees and the organization to perform specific nuclear power related multi-discipline function independently and competitively

  14. Uses of Effective Field Theory in Lattice QCD

    OpenAIRE

    Kronfeld, Andreas S.

    2002-01-01

    Several physical problems in particle physics, nuclear physics, and astrophysics require information from non-perturbative QCD to gain a full understanding. In some cases the most reliable technique for quantitative results is to carry out large-scale numerical calculations in lattice gauge theory. As in any numerical technique, there are several sources of uncertainty. This chapter explains how effective field theories are used to keep them under control and, then, obtain a sensible error ba...

  15. Effectively Managing Nuclear Risk Through Human Performance Improvement

    International Nuclear Information System (INIS)

    Coe, Richard; Lake, Patricia

    2003-01-01

    The U.S. commercial nuclear industry has just completed an outstanding decade of plant performance. Safety levels and electric production are at unprecedented high levels and continue to exceed even high industry goals. Nuclear energy continues to keep the highest priority on performance improvement programs and highly trained and qualified people that maintain its record setting safety and reliability of operations. While the industry has maintained a high level of performance, the advent of deregulation and the consolidation of nuclear power plant ownership, as well as the current climate for concern about both rising energy costs and the availability of power, have raised the standard for nuclear energy's level of competitiveness in today's market place. The resulting challenge is how to more effectively manage risk and to improve performance even further in a generally high-performing industry. One of the most effective ways to develop this culture is to apply the principles of Hum an Performance Technology, or HPT. HPT is a relatively new field. Its principles are derived from the research and practice of behavioral and cognitive psychologists, instructional technologists, training designers, organizational developers, and various human resource specialists. Using the principles of HPT can help the nuclear industry successfully meet ever-changing environmental and business demands

  16. Deregulation in the field of decommissioning and dismantling of nuclear facilities

    International Nuclear Information System (INIS)

    Kurz, A.

    1994-05-01

    The report comprises two articles covering current topics of the decommissioning and dismantling of nuclear facilities. In the first article written by Kurz, the legal standards are listed together with conclusions and proposals regarding their implementation for the further development of this field of law. The article by Baumgaertel is aimed at evaluating the regulations governing nuclear technology as regards their applicability to the decommissioning and dismantling of nuclear facilities. These articles shall contribute to the discussions taking place in this field at the moment. As a result, an appropriate and project-specific application of the legal provisions and not legally binding (technical) regulations in the field of nuclear technology (deregulation) in the licensing procedures required for the decommissioning and dismantling of nuclear facilities is requested by the authors. (orig.) [de

  17. A Study on Human Resources Development in Nuclear Field

    International Nuclear Information System (INIS)

    Moon, Keehwan; Lee, M. K.; Kim, S. S.; Nam, J. H.; Won, B. C.; Lee, D. S; Hwang, I. A.; Seo, M. W.

    2011-11-01

    The study encompasses 4 major parts, each results being described here under: Various policy alternatives through supply-demand analysis of domestic nuclear skilled manpower are suggested. Human resources development programs of main educational organizations in domestic and overseas are comprehensively reviewed. Establishment of 'Integrated Management Organization' which can combine and manage domestic educational organizations' educational functions is necessary to efficiently deal with the increased educational demand and the shift of educational paradigm from supply-driven to needs-driven education and to make nuclear energy export sustainable. And road map on human resource development to efficiently accomplish 'Integrated Management Organization's mission is suggested. It is provided that an overall strategies for the reasonable educational program reflecting the good practices with their implications in overseas nuclear education programs

  18. Memory effects in nuclear fragmentation?

    International Nuclear Information System (INIS)

    Colonna, M.; Di Toro, M.; Guarnera, A.

    1994-01-01

    A general procedure to identify instability regions which lead to multifragmentation events is presented. The dominant mode at the instability point is determined from the knowledge of the mean properties (density and temperature) of the system at that point. For spinodal instabilities the dependence of fragment structures on the dynamical conditions is studied changing the beam energy and the considered equation of state. An important competition between two dynamical effects, expansion of the system and growth of fluctuations, is revealed. It is shown that in heavy-ion central collisions at medium energies memory effects of the configuration formed at the instability time could be observed in the final fragmentation pattern. Some hints towards a fully dynamical picture of fragmentation processes are finally suggested. ((orig.))

  19. The Romanian educational system in nuclear engineering field - experience and new approaches

    International Nuclear Information System (INIS)

    Dragusin, O.; Burghelea, A.

    2001-01-01

    In this paper we would like to present the actual status of the education in the nuclear engineering field at 'Pantholic' University Bucharest, Romania, Power Engineering Faculty, Nuclear Power Plant Department, and also the efforts of integration of the educational system of Romania into the international system and the development of new concepts concerning the education of the new specialists generation. (authors)

  20. Dosimetry of the Embalse nuclear power plant neutron/gamma mixed fields

    International Nuclear Information System (INIS)

    Salas, C.A.

    1990-01-01

    The aim of this work is to describe the method used at the Embalse nuclear power plant for carrying out personal dosimetry of the agents affected to the tasks on the Embalse nuclear power plant neutron-gamma mixed fields. (Author) [es

  1. Optimal usage of computing grid network in the fields of nuclear fusion computing task

    International Nuclear Information System (INIS)

    Tenev, D.

    2006-01-01

    Nowadays the nuclear power becomes the main source of energy. To make its usage more efficient, the scientists created complicated simulation models, which require powerful computers. The grid computing is the answer to powerful and accessible computing resources. The article observes, and estimates the optimal configuration of the grid environment in the fields of the complicated nuclear fusion computing tasks. (author)

  2. Surface effects of underground nuclear explosions

    Energy Technology Data Exchange (ETDEWEB)

    Allen, B.M.; Drellack, S.L. Jr.; Townsend, M.J.

    1997-06-01

    The effects of nuclear explosions have been observed and studied since the first nuclear test (code named Trinity) on July 16, 1945. Since that first detonation, 1,053 nuclear tests have been conducted by the US, most of which were sited underground at the Nevada Test Site (NTS). The effects of underground nuclear explosions (UNEs) on their surroundings have long been the object of much interest and study, especially for containment, engineering, and treaty verification purposes. One aspect of these explosion-induced phenomena is the disruption or alteration of the near-surface environment, also known as surface effects. This report was prepared at the request of the Los Alamos National Laboratory (LANL), to bring together, correlate, and preserve information and techniques used in the recognition and documentation of surface effects of UNEs. This report has several main sections, including pertinent background information (Section 2.0), descriptions of the different types of surface effects (Section 3.0), discussion of their application and limitations (Section 4.0), an extensive bibliography and glossary (Section 6.0 and Appendix A), and procedures used to document geologic surface effects at the NTS (Appendix C). Because a majority of US surface-effects experience is from the NTS, an overview of pertinent NTS-specific information also is provided in Appendix B. It is not within the scope of this report to explore new relationships among test parameters, physiographic setting, and the types or degree of manifestation of surface effects, but rather to compile, summarize, and capture surface-effects observations and interpretations, as well as documentation procedures and the rationale behind them.

  3. Towards accurate simulation of fringe field effects

    International Nuclear Information System (INIS)

    Berz, M.; Erdelyi, B.; Makino, K.

    2001-01-01

    In this paper, we study various fringe field effects. Previously, we showed the large impact that fringe fields can have on certain lattice scenarios of the proposed Neutrino Factory. Besides the linear design of the lattice, the effects depend strongly on the details of the field fall off. Various scenarios are compared. Furthermore, in the absence of detailed information, we study the effects for the LHC, a case where the fringe fields are known, and try to draw some conclusions for Neutrino Factory lattices

  4. Effective Field Theory on Manifolds with Boundary

    Science.gov (United States)

    Albert, Benjamin I.

    In the monograph Renormalization and Effective Field Theory, Costello made two major advances in rigorous quantum field theory. Firstly, he gave an inductive position space renormalization procedure for constructing an effective field theory that is based on heat kernel regularization of the propagator. Secondly, he gave a rigorous formulation of quantum gauge theory within effective field theory that makes use of the BV formalism. In this work, we extend Costello's renormalization procedure to a class of manifolds with boundary and make preliminary steps towards extending his formulation of gauge theory to manifolds with boundary. In addition, we reorganize the presentation of the preexisting material, filling in details and strengthening the results.

  5. ILK statement about the preservation of competence in the nuclear field in Germany

    International Nuclear Information System (INIS)

    Anon.

    2004-01-01

    The rapid expansion of nuclear power in many countries was accompanied by an equally rapid buildup of personnel in research and education. German universities had established curricula tailored to the needs of nuclear technology. When the buildup phase had come to an end, manpower was reduced especially in the vendor industries. Over the past ten years, many German universities have adapted to this development by either discontinuing or greatly restricting courses in nuclear technology. ILK is afraid that the progressive reduction of nuclear technology education - also against the background of the opt-out of the use of nuclear power preferred by the German federal government - and a persistently low level of interest, especially among qualified young scientists and engineers, in nuclear technology studies could give rise to a situation in which the preservation of knowledge and know-how in nuclear technology as well as that of a core of competent personnel could be jeopardized. Today's requirements include not only in-depth education in nuclear technology but also the ability to acquire elementary knowledge in the field within the framework of basic studies, or a general studies course, as an interdisciplinary approach. Moreover, education in nuclear technology should not be limited to 'classical' nuclear reactor technology and reactor physics, but increasingly take into account aspects of radiation protection, radiobiology, waste management, systems analysis, risk management, and also nuclear law. More detailed recommendations are given of a systematic approach to the requirements of qualified, comprehensive education in nuclear technology and its structural requirements. (orig.)

  6. Nuclearity, split-property and duality for the Klein-Gordon field in curved spacetime

    International Nuclear Information System (INIS)

    Verch, R.

    1993-05-01

    Nuclearity, Split-Property and Duality are establihed for the nets of von Neumann algebras associated with the representations of distinguished states of the massive Klein-Gordon field propagating in particular classes of curved spacetimes. (orig.)

  7. Application of transient magnetic field to the measurement of nuclear magnetic moments

    International Nuclear Information System (INIS)

    Ribas, R.V.

    1987-01-01

    A review on: the mechanism for producing transient magnetic field; techniques for measuring nuclear gyromagnetic factor; and some examples of recent measurements using this technique is presented. (M.C.K.) [pt

  8. Recommendable Practices for Effective Nuclear Crisis Communication

    International Nuclear Information System (INIS)

    Lee, Chang Ju; Hah, Yeon Hee

    2011-01-01

    'Crisis communication' refers one of the activities done by the Nuclear Regulatory Organizations (NROs) in order to protect the public and the environment from the possible harmful effects. As denoted by the BMU, German NRO, crisis communication is not only 'public information' or 'information for the public', but also communication between authorities in order to guarantee that public information is consistent. This study proposes some recommendable practices for developing a guideline of well-prepared nuclear crisis communication system, including its management framework, and for introducing good insights, based on the study of international aspects provided by relevant OECD/NEA WPGC (Working Group on Public Communication for Nuclear Regulatory Organizations)i working group

  9. Thermodynamic coupling of heat and matter flows in near-field regions of nuclear waste repositories

    International Nuclear Information System (INIS)

    Carnahan, C.L.

    1983-11-01

    In near-field regions of nuclear waste repositories, thermodynamically coupled flows of heat and matter can occur in addition to the independent flows in the presence of gradients of temperature, hydraulic potential, and composition. The following coupled effects can occur: thermal osmosis, thermal diffusion, chemical osmosis, thermal filtration, diffusion thermal effect, ultrafiltration, and coupled diffusion. Flows of heat and matter associated with these effects can modify the flows predictable from the direct effects, which are expressed by Fourier's law, Darcy's law, and Fick's law. The coupled effects can be treated quantitatively together with the direct effects by the methods of the thermodynamics of irreversible processes. The extent of departure of fully coupled flows from predictions based only on consideration of direct effects depends on the strengths of the gradients driving flows, and may be significant at early times in backfills and in near-field geologic environments of repositories. Approximate calculations using data from the literature and reasonable assumptions of repository conditions indicate that thermal-osmotic and chemical-osmotic flows of water in semipermeable backfills may exceed Darcian flows by two to three orders of magnitude, while flows of solutes may be reduced greatly by ultrafiltration and chemical osmosis, relative to the flows predicted by advection and diffusion alone. In permeable materials, thermal diffusion may contribute to solute flows to a smaller, but still significant, extent

  10. Climatic Effects of Regional Nuclear War

    Science.gov (United States)

    Oman, Luke D.

    2011-01-01

    We use a modern climate model and new estimates of smoke generated by fires in contemporary cities to calculate the response of the climate system to a regional nuclear war between emerging third world nuclear powers using 100 Hiroshima-size bombs (less than 0.03% of the explosive yield of the current global nuclear arsenal) on cities in the subtropics. We find significant cooling and reductions of precipitation lasting years, which would impact the global food supply. The climate changes are large and longlasting because the fuel loadings in modern cities are quite high and the subtropical solar insolation heats the resulting smoke cloud and lofts it into the high stratosphere, where removal mechanisms are slow. While the climate changes are less dramatic than found in previous "nuclear winter" simulations of a massive nuclear exchange between the superpowers, because less smoke is emitted, the changes seem to be more persistent because of improvements in representing aerosol processes and microphysical/dynamical interactions, including radiative heating effects, in newer global climate system models. The assumptions and calculations that go into these conclusions will be described.

  11. Communication patterns in the field of nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Tomov, D.; Filipov, F.; Kolev, N.

    1986-01-01

    A scientometric analysis of publications presented in four secondary information sources on the problem of nuclear magnetic resonance in physics, biomedicine and technology was carried out. A dynamic growth of the number of articles in biomedicine over 1982 to 1984 was established. Secondary publications play an important role in scientific communications as revealed by citation analysis. (author)

  12. Nuclear power and the greenhouse effect

    International Nuclear Information System (INIS)

    1989-01-01

    Carbon dioxide from fossil fuel combustion accounts for about 40% of the global warming due to the 'greenhouse effect'. Thus national energy policies of the fuels used to generate electricity can have a significant effect on the levels of gas emissions which contribute to the 'greenhouse effect'. The more efficient use of energy is the first way of controlling the increase in gas emissions. The use of natural gas instead of coal or oil would also be beneficial but the reserves of natural gas are limited. The use of nuclear-generated electricity has already reduced the level of global warming by 3% but could have a greater effect in the future. Ways in which the government could reduce 'greenhouse' gas emissions are listed. These include the more extensive use of nuclear power for generating electricity not only for domestic but industrial uses. (U.K.)

  13. An introduction to effective field theory

    International Nuclear Information System (INIS)

    Donoghue, John F.

    1999-01-01

    In these lectures I describe the main ideas of effective field theory. These are first illustrated using QED and the linear sigma model as examples. Calculational techniques using both Feynman diagrams and dispersion relations are introduced. Within QCD, chiral perturbation theory is a complete effective field theory, and I give a guide to some calculations in the literature which illustrates key ideas. (author)

  14. Application of the Integrated Signal Converting Circuit in the Nuclear Fields

    International Nuclear Information System (INIS)

    Kim, Young Choon; Sohn, Chang Ho; Kim, Jung Seon; Kim, Min Kyu

    2005-01-01

    In the present nuclear fields, all Instrument and Control (I and C) applications are operating by the analog method using the analog device and passive things. It is hard to make miniaturization of modules and robust system against noise, reliability is decreased also because malfunctions are occurred very often. In order to solve these problems, we suggest that adopt the digital method using the digital device and active things in the nuclear fields. In these papers represented, from these results of the investigation

  15. Application of the Integrated Signal Converting Circuit in the Nuclear Fields

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Choon; Sohn, Chang Ho; Kim, Jung Seon; Kim, Min Kyu [Samchang Enterprise Co., Ltd., Ulsan (Korea, Republic of)

    2005-07-01

    In the present nuclear fields, all Instrument and Control (I and C) applications are operating by the analog method using the analog device and passive things. It is hard to make miniaturization of modules and robust system against noise, reliability is decreased also because malfunctions are occurred very often. In order to solve these problems, we suggest that adopt the digital method using the digital device and active things in the nuclear fields. In these papers represented, from these results of the investigation.

  16. Biological effects of electromagnetic fields

    African Journals Online (AJOL)

    2012-02-28

    Feb 28, 2012 ... radiofrequency emitting sources are radars, mobile phones and their base stations, ... and industrial applications, could have effect on living organisms. ...... Hazards of Electromagnetic Pollution (Msc Thesis). Department of ...

  17. More effective field theory for non-relativistic scattering

    International Nuclear Information System (INIS)

    Kaplan, D.B.

    1997-01-01

    An effective field theory treatment of nucleon-nucleon scattering at low energy shows much promise and could prove to be a useful tool in the study of nuclear matter at both ordinary and extreme densities. The analysis is complicated by the existence a large length scale - the scattering length -which arises due to couplings in the short distance theory being near critical values. I show how this can be dealt with by introducing an explicit s-channel state in the effective field theory. The procedure is worked out analytically in a toy example. I then demonstrate that a simple effective field theory excellently reproduces the 1 S 0 np phase shift up to the pion production threshold. (orig.)

  18. Radiation effects, nuclear energy and comparative risks

    International Nuclear Information System (INIS)

    Gopinath, D.V.

    2007-01-01

    Nuclear energy had a promising start as an unlimited, inexpensive and environmentally benign source of energy for electricity generation. However, over the decades its growth was severely retarded due to concerns about its possible detrimental effects on the well-being of mankind and the environment. Since such concerns are essentially due to the gigantic magnitude of radioactivity and ionizing radiations associated with nuclear energy, this article starts with a comprehensive account of effects of the ionizing radiation on living systems. Quantitative description of types of radiation exposure and their varied effects is given. The origin, type and magnitude of mutagenic effects of radiation are described. The concept of radiation risk factors, basis for their evaluation and their currently accepted values are presented. With this background, origin and magnitude of radioactivity and associated ionizing radiations in nuclear reactors are presented and the elaborate measures to contain them are described. It is recognized that notwithstanding all the measures taken in the nuclear industry, certain amount of radiation exposure, however small, is inevitable and the values, based on the experience world over, are presented. Estimated health risk due to such exposures is evaluated. For a comparative analysis, risks in other options of electricity generation such as hydel and fossil-fuelled plants are described. It is seen that on an overall basis, the nuclear option is no more risky than the other commonly employed options, and is in fact, significantly less. Lastly, since every option of electricity generation entails some risk, the case of 'no addition of electricity, and its impact on the society are considered. Based on the analysis of extensive data provided by UNDP on the human development parameters for different countries in the world, it is shown that at least for developing countries, any option of addition of electricity would be far more desirable than the

  19. Activities of Brazilian Nuclear Energy Commission in the field of nuclear power plant licesing

    International Nuclear Information System (INIS)

    Alves, R.N.

    1986-01-01

    The objectives, the procedures and the ways of implementation of measures aiming at safety use of nuclear energy are presented. The juridical aspects in the licensing area and the regulatory activities used by CNEN. The description of nuclear power plants and the methodology used in studies of environmental protection and radiation protection are presented [pt

  20. Study on temperature field airborne remote sensing survey along shore nuclear power station in different tide status

    International Nuclear Information System (INIS)

    Liang Chunli; Li Mingsong

    2010-01-01

    Nuclear Power Station needs to let large quantity of cooling water to the near sea area when it is running. Whether the cooling water has effect to surrounding environment and the running of Nuclear Power Station needs further research. Temperature Drainage Mathematic Model and Physical Analogue Model need to acquire the distribution characteristic of near Station sea surface temperature field in different seasons and different tide status. Airborne Remote Sending Technique has a advantage in gaining high resolution sea surface temperature in different tide status, and any other manual method with discrete point survey can not reach it. After a successful implementation of airborne remote sensing survey to gain the near-shore temperature drainage information in Qinshan Nuclear Power Station, it provides the reference methods and ideas for temperature drainage remote sensing survey of Nuclear Power Station. (authors)

  1. Bilateral agreements in the field of nuclear trade and technology

    International Nuclear Information System (INIS)

    Di Primio, J.C.

    1989-03-01

    This report analyses the evolution of the Non-Proliferation Treaty and the non-proliferation regime since the nineteen sixties from the angle of an interdisciplinary approach. The medium- and long-term issues of non-proliferation are identified and discussed in connection with the NPT revisional conference to be held in 1990, and the NPT extension conference in 1995. The major subjects under review include: the international safeguards system; NP aspects of new technologies; bilateral agreements on cooperation in nuclear energy; developments on the international nuclear market; arms control issues of relevance to the NPT; the non-proliferation interests of the Federal Republic of Germany. Looking ahead to the conferences in 1990 and 1995, the report reveals some major aspects and recommendations for consideration in decisions on the future line of non-proliferation policy pursued by the Federal German government. (orig./HP) [de

  2. Nuclear compression effects on pion production in nuclear collisions

    International Nuclear Information System (INIS)

    Sano, M.; Gyulassy, M.; Wakai, M.; Kitazoe, Y.

    1984-11-01

    The pion multiplicity produced in nuclear collisions between 0.2 and 2 AGeV is calculated assuming shock formation. We also correct the procedure of extracting the nuclear equation of state as proposed by Stock et al. The nuclear equation of state would have to be extremely stiff for this model to reproduce the observed multiplicities. The assumptions of this model are critically analyzed. (author)

  3. Decommissioning and cutting methods in the nuclear field

    Energy Technology Data Exchange (ETDEWEB)

    Bensoussan, E. [Protem SAS, 26 - Etoile sur Rhone (France)

    2008-07-01

    A few states started in the early forties/fifties the first development of nuclear technologies. Some of them now own a great amount of nuclear installations which entirely fulfill their assignment. In some cases, the life time of the nuclear power plants which were scheduled for approximately 30 years have been extended by more than 50%, the other ones as well as fuel production and enrichment plants, experimental or research reactors, will have to be dismantled in the near future. The decommissioning of those installations is definitely one of the twenty first century challenge. It is differently managed depending on the countries and their energetic and development policies, their financial consideration, the availability of qualified engineers or specialized companies to handle such projects. The final aim of decommissioning is to recover the geographic site in its original condition. A real cooperation is existing in between the people involved in different countries through different types of conferences and meetings during which the main subjects are: - The safety of the operators during all the phases of decommissioning operations. - Restrictions and dimensioning of the required equipment - Storage and waste management - Elaboration of procedures for recording all different steps and processes. Some of the techniques are described in this paper without being exhaustive. (author)

  4. Decommissioning and cutting methods in the nuclear field

    International Nuclear Information System (INIS)

    Bensoussan, E.

    2008-01-01

    A few states started in the early forties/fifties the first development of nuclear technologies. Some of them now own a great amount of nuclear installations which entirely fulfill their assignment. In some cases, the life time of the nuclear power plants which were scheduled for approximately 30 years have been extended by more than 50%, the other ones as well as fuel production and enrichment plants, experimental or research reactors, will have to be dismantled in the near future. The decommissioning of those installations is definitely one of the twenty first century challenge. It is differently managed depending on the countries and their energetic and development policies, their financial consideration, the availability of qualified engineers or specialized companies to handle such projects. The final aim of decommissioning is to recover the geographic site in its original condition. A real cooperation is existing in between the people involved in different countries through different types of conferences and meetings during which the main subjects are: - The safety of the operators during all the phases of decommissioning operations. - Restrictions and dimensioning of the required equipment - Storage and waste management - Elaboration of procedures for recording all different steps and processes. Some of the techniques are described in this paper without being exhaustive. (author)

  5. Strengthened International Nuclear Safeguards; burdens and Effects on Nuclear Technology Development

    International Nuclear Information System (INIS)

    Badawy, I.

    2000-01-01

    The present paper deals with the recent direction of strengthening the international nuclear safeguards and the effects on the development of nuclear technology for peaceful applications. The new basic principles for strengthening the international nuclear control in the direction of undeclared nuclear activities are elaborated, and the national obligations are indicated. The burdens on the development of nuclear technology are discussed. Approaches are proposed in this work for coping with the present and future situations

  6. Field emission current from a junction field-effect transistor

    International Nuclear Information System (INIS)

    Monshipouri, Mahta; Abdi, Yaser

    2015-01-01

    Fabrication of a titanium dioxide/carbon nanotube (TiO 2 /CNT)-based transistor is reported. The transistor can be considered as a combination of a field emission transistor and a junction field-effect transistor. Using direct current plasma-enhanced chemical vapor deposition (DC-PECVD) technique, CNTs were grown on a p-typed (100)-oriented silicon substrate. The CNTs were then covered by TiO 2 nanoparticles 2–5 nm in size, using an atmospheric pressure CVD technique. In this device, TiO 2 /CNT junction is responsible for controlling the emission current. High on/off-current ratio and proper gate control are the most important advantages of device. A model based on Fowler–Nordheim equation is utilized for calculation of the emission current and the results are compared with experimental data. The effect of TiO 2 /CNT hetero-structure is also investigated, and well modeled

  7. Biological Effects of Electromagnetic Fields

    Science.gov (United States)

    2006-11-27

    Warning stimuli, as well as learning material, i.e. the numbers to recall, were presented binaurally via earphones at an intensity of 65dB sound...ensued in a remarkable increase in the yield of ES-derived spontaneously beating cardiomyocytes. Figure 3 Effect of MF on...move the mucus along a surface layer of saline. This is very likely that the cilia, beating with the frequency about few tenth of Hertz, generate some

  8. Abstract of results of safety study. Nuclear fuel cycle field in fiscal 2003

    International Nuclear Information System (INIS)

    2004-11-01

    This report descried the results of studies of nuclear fuel cycle field (nuclear fuel facilities, seismic design, all subjects of environmental radiation and waste disposal, and subjects on nuclear fuel cycle in probabilistic safety assessment) in fiscal 2003 on the basis of the principle project of safety study (from fiscal 2001 to 2005). It consists of four chapters; the first chapter is outline of the principle of project, the second is objects and subjects of safety study in the nuclear fuel cycle field, the third list of questionnaire of results of safety study and the forth investigation of results of safety study in fiscal 2003. There are 49 lists, which include 22 reports on the nuclear fuel facility, one on the seismic design, 4 on the probabilistic safety assessment, 7 on the environmental radiation and 15 on the waste disposal. (S.Y.)

  9. CFD analysis of moderator flow and temperature fields inside a vertical calandria vessel of nuclear reactor

    International Nuclear Information System (INIS)

    Kansal, Anuj Kumar; Joshi, Jyeshtharaj B.; Maheshwari, Naresh Kumar; Vijayan, Pallippattu Krishnan

    2015-01-01

    Highlights: • 3D CFD of vertical calandria vessel. • Spatial distribution of volumetric heat generation. • Effect of Archimedes number. • Non-dimensional analysis. - Abstract: Three dimensional computational fluid dynamics (CFD) analysis has been performed for the moderator flow and temperature fields inside a vertical calandria vessel of nuclear reactor under normal operating condition using OpenFOAM CFD code. OpenFOAM is validated by comparing the predicted results with the experimental data available in literature. CFD model includes the calandria vessel, calandria tubes, inlet header and outlet header. Analysis has been performed for the cases of uniform and spatial distribution of volumetric heat generation. Studies show that the maximum temperature in moderator is lower in the case of spatial distribution of heat generation as compared to that in the uniform heat generation in calandria. In addition, the effect of Archimedes number on maximum and average moderator temperature was investigated

  10. CFD analysis of moderator flow and temperature fields inside a vertical calandria vessel of nuclear reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kansal, Anuj Kumar, E-mail: akansal@barc.gov.in [Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Joshi, Jyeshtharaj B., E-mail: jbjoshi@gmail.com [Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094 (India); Maheshwari, Naresh Kumar, E-mail: nmahesh@barc.gov.in [Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Vijayan, Pallippattu Krishnan, E-mail: vijayanp@barc.gov.in [Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2015-06-15

    Highlights: • 3D CFD of vertical calandria vessel. • Spatial distribution of volumetric heat generation. • Effect of Archimedes number. • Non-dimensional analysis. - Abstract: Three dimensional computational fluid dynamics (CFD) analysis has been performed for the moderator flow and temperature fields inside a vertical calandria vessel of nuclear reactor under normal operating condition using OpenFOAM CFD code. OpenFOAM is validated by comparing the predicted results with the experimental data available in literature. CFD model includes the calandria vessel, calandria tubes, inlet header and outlet header. Analysis has been performed for the cases of uniform and spatial distribution of volumetric heat generation. Studies show that the maximum temperature in moderator is lower in the case of spatial distribution of heat generation as compared to that in the uniform heat generation in calandria. In addition, the effect of Archimedes number on maximum and average moderator temperature was investigated.

  11. RADIATION EFFECTS IN NUCLEAR WASTE MATERIALS

    International Nuclear Information System (INIS)

    Weber, William J.

    2000-01-01

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

  12. Nuclear energy: a new action field for the ITCR

    International Nuclear Information System (INIS)

    1992-01-01

    This congress has the objective to give new orientations, which can consolidate the Instituto Tecnologico de Costa Rica, as an institution for superior education, that can asume leadership in the field of science and technology

  13. Permeabilization of the nuclear envelope following nanosecond pulsed electric field exposure

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Gary L., E-mail: gary.l.thompson.3@gmail.com [Oak Ridge Institute for Science & Education, Joint Base San Antonio Fort Sam Houston, TX, 78234 (United States); Roth, Caleb C. [Department of Radiological Sciences, University of Texas Health Science Center at San Antonio, TX, 78234 (United States); Kuipers, Marjorie A. [Radio Frequency Radiation Branch, Bioeffects Division, Human Effectiveness Directorate, 711th Human Performance Wing, Air Force Research Laboratory, Joint Base San Antonio Fort Sam Houston, TX, 78234 (United States); Tolstykh, Gleb P. [General Dynamics IT, Joint Base San Antonio Fort Sam Houston, TX, 78234 (United States); Beier, Hope T. [Optical Radiation Branch, Bioeffects Division, Human Effectiveness Directorate, 711th Human Performance Wing, Air Force Research Laboratory, Joint Base San Antonio Fort Sam Houston, TX, 78234 (United States); Ibey, Bennett L. [Radio Frequency Radiation Branch, Bioeffects Division, Human Effectiveness Directorate, 711th Human Performance Wing, Air Force Research Laboratory, Joint Base San Antonio Fort Sam Houston, TX, 78234 (United States)

    2016-01-29

    Permeabilization of cell membranes occurs upon exposure to a threshold absorbed dose (AD) of nanosecond pulsed electric fields (nsPEF). The ultimate, physiological bioeffect of this exposure depends on the type of cultured cell and environment, indicating that cell-specific pathways and structures are stimulated. Here we investigate 10 and 600 ns duration PEF effects on Chinese hamster ovary (CHO) cell nuclei, where our hypothesis is that pulse disruption of the nuclear envelope membrane leads to observed cell death and decreased viability 24 h post-exposure. To observe short-term responses to nsPEF exposure, CHO cells have been stably transfected with two fluorescently-labeled proteins known to be sequestered for cellular chromosomal function within the nucleus – histone-2b (H2B) and proliferating cell nuclear antigen (PCNA). H2B remains associated with chromatin after nsPEF exposure, whereas PCNA leaks out of nuclei permeabilized by a threshold AD of 10 and 600 ns PEF. A downturn in 24 h viability, measured by MTT assay, is observed at the number of pulses required to induce permeabilization of the nucleus. - Highlights: • The ability of nsPEF to damage nuclear structures within cells is investigated. • Leakage of proliferating nuclear antigen from nuclei is induced by nsPEF. • High doses of nsPEF disrupt cortical lamin and cause chromatin decompaction. • Histone H2B remains attached to chromatin following nsPEF exposure. • DNA does not leak out of nsPEF-permeabilized nuclei.

  14. Effect of magnetic field on food freezing

    OpenAIRE

    村田, 圭治; 奥村, 太一; 荒賀, 浩一; 小堀, 康功

    2010-01-01

    [Abstract] This paper presents an experimental investigation on effects of magnetic field on food freezing process. Although purpose of food freezing is to suppress the deterioration of food, freezing breaks food tissue down, and some nutrient and delicious element flow out after thawing. Recently, a few of refrigeration equipments with electric and magnetic fields have attracted attention from food production companies and mass media. Water and tuna were freezed in magnetic field (100kH, 1.3...

  15. Boundary effects on quantum field theories

    International Nuclear Information System (INIS)

    Lee, Tae Hoon

    1991-01-01

    Quantum field theory in the S 1 *R 3 space-time is simply described by the imaginary time formalism. We generalize Schwinger-DeWitt proper-time technique which is very useful in zero temperature field theories to this case. As an example we calculate the one-loop effective potential of the finite temperature scala field theory by this technique.(Author)

  16. The effects of nuclear war. 2. rev. enl. ed.

    International Nuclear Information System (INIS)

    Rodejohann, J.

    1982-01-01

    Possible and probable effects of a nuclear war in Europe are described on the basis of a study by the Office of Technology Assessment, US Kongress ('The effects of nuclear war', Wash. D.C. 1979). (HP) [de

  17. Effect of the Fukushima nuclear disaster on global public acceptance of nuclear energy

    International Nuclear Information System (INIS)

    Kim, Younghwan; Kim, Minki; Kim, Wonjoon

    2013-01-01

    The Fukushima nuclear disaster has significantly changed public attitudes toward nuclear energy. It is important to understand how this change has occurred in different countries before the global community revises existing nuclear policies. This study examines the effect of the Fukushima disaster on public acceptance of nuclear energy in 42 countries. We find that the operational experience of nuclear power generation which has significantly affected positive public opinion about nuclear energy became considerably negative after the disaster, suggesting fundamental changes in public acceptance regardless of the level of acceptance before the disaster. In addition, contrary to our expectation, the proportion of nuclear power generation is positively and significantly related to public acceptance of nuclear energy after the Fukushima accident and government pressure on media content led to a greater decrease in the level of public acceptance after the accident. Nuclear energy policymakers should consider the varied factors affecting public acceptance of nuclear energy in each country depending on its historical, environmental, and geographical circumstances before they revise nuclear policy in response to the Fukushima accident. - Highlights: • Fukushima accident has negatively changed public attitudes toward nuclear energy. • Effect of operational experience became considerably negative after the accident. • Effect of proportion of nuclear power generation is positive after the accident. • Effect of government pressure on media content became negative after the accident. • Country specific policy responses on nuclear public acceptance are required

  18. Effective field theory for NN interactions

    International Nuclear Information System (INIS)

    Tran Duy Khuong; Vo Hanh Phuc

    2003-01-01

    The effective field theory of NN interactions is formulated and the power counting appropriate to this case is reviewed. It is more subtle than in most effective field theories since in the limit that the S-wave NN scattering lengths go to infinity. It is governed by nontrivial fixed point. The leading two body terms in the effective field theory for nucleon self interactions are scale invariant and invariant under Wigner SU(4) spin-isospin symmetry in this limit. Higher body terms with no derivatives (i.e. three and four body terms) are automatically invariant under Wigner symmetry. (author)

  19. Preface: Special Topic on Nuclear Quantum Effects.

    Science.gov (United States)

    Tuckerman, Mark; Ceperley, David

    2018-03-14

    Although the observable universe strictly obeys the laws of quantum mechanics, in many instances, a classical description that either ignores quantum effects entirely or accounts for them at a very crude level is sufficient to describe a wide variety of phenomena. However, when this approximation breaks down, as is often the case for processes involving light nuclei, a full quantum treatment becomes indispensable. This Special Topic in The Journal of Chemical Physics showcases recent advances in our understanding of nuclear quantum effects in condensed phases as well as novel algorithmic developments and applications that have enhanced the capability to study these effects.

  20. Preface: Special Topic on Nuclear Quantum Effects

    Science.gov (United States)

    Tuckerman, Mark; Ceperley, David

    2018-03-01

    Although the observable universe strictly obeys the laws of quantum mechanics, in many instances, a classical description that either ignores quantum effects entirely or accounts for them at a very crude level is sufficient to describe a wide variety of phenomena. However, when this approximation breaks down, as is often the case for processes involving light nuclei, a full quantum treatment becomes indispensable. This Special Topic in The Journal of Chemical Physics showcases recent advances in our understanding of nuclear quantum effects in condensed phases as well as novel algorithmic developments and applications that have enhanced the capability to study these effects.

  1. The deterrent effect of nuclear forensics: The case of Hungary

    International Nuclear Information System (INIS)

    Gil, Laura

    2016-01-01

    A State capable of identifying the origin and history of intercepted nuclear or radioactive material can have a deterrent effect. This is why nuclear forensics — the examination of nuclear and other radioactive material as part of criminal or nuclear security investigations — is an important tool.

  2. Information about the field of nuclear waste 1986

    International Nuclear Information System (INIS)

    1986-01-01

    The Consultative Committee for Nuclear Waste Management (KASAM) reports about the knowledge 1986 concerning the management and the ultimate storage of radioactive wastes. In the report discusses ethical aspects, technical and scientific problems related to the radioactive waste disposal. Still there is no plant in the world build for ultimate storage of high-level radioactive wastes, but many states have plans for building such plants. The report gives a survey of different storage technics, chemical, hydrochemical and radioecological problems. Some international and national programs are reviewed. (K.A.E.)

  3. Lightning effects on electrical and nuclear equipment

    International Nuclear Information System (INIS)

    Gary, C.

    1986-01-01

    This paper gives the physical bases on which lightning protection of buildings and other erections such as nuclear power stations depend. To this end it first examines the impact phenomena of lightning, the operating systems of lightning conductors and methods of protection using metal mesh. It then describes various secondary effects of lightning, particularly those which occur inside buildings as a result of the potential rise in earthing systems and electromagnetic induction phenomena. 18 refs [fr

  4. Application of γ field theory based calculation method to the monitoring of mine nuclear radiation environment

    International Nuclear Information System (INIS)

    Du Yanjun; Liu Qingcheng; Liu Hongzhang; Qin Guoxiu

    2009-01-01

    In order to find the feasibility of calculating mine radiation dose based on γ field theory, this paper calculates the γ radiation dose of a mine by means of γ field theory based calculation method. The results show that the calculated radiation dose is of small error and can be used to monitor mine environment of nuclear radiation. (authors)

  5. Principles of nuclear magnetic resonance imaging using an inhomogeneous polarizing field

    International Nuclear Information System (INIS)

    Briguet, A.; Chaillout, J.; Goldman, M.

    1985-01-01

    In this paper, it is indicated how to reconstruct nuclear magnetic resonance images acquired in an inhomogeneous static magnetic field without the previous knowledge of its spatial distribution. The method provides also the map of the static magnetic field through the sample volume; furthermore it allows the use of non uniform but spatially controlled encoding gradients [fr

  6. Multi-fields' coordination information integrated platform for nuclear power plant operation preparation

    International Nuclear Information System (INIS)

    Yuan Chang; Li Yong; Ye Zhiqiang

    2011-01-01

    To realize the coordination in multi-fields' work and information sharing, by applying the method of Enterprise Architecture (EA), the business architecture, functional flow and application architecture of Nuclear Power Plant's operation preparation information integrated platform are designed, which can realize the information sharing and coordination of multi fields. (authors)

  7. Political aspects of nuclear test effects at Semipalatinsk nuclear test site

    International Nuclear Information System (INIS)

    Sydykov, E.B.; Panin, M.S.

    2003-01-01

    The paper describes tense struggle of Kazakhstan people for closure of the Semipalatinsk Nuclear Test Site. It reveals major foreign policy aspects and nuclear test effects for both Kazakhstan and the world community. (author)

  8. Quantum Nuclear Extension of Electron Nuclear Dynamics on Folded Effective-Potential Surfaces

    DEFF Research Database (Denmark)

    Hall, B.; Deumens, E.; Ohrn, Y.

    2014-01-01

    A perennial problem in quantum scattering calculations is accurate theoretical treatment of low energy collisions. We propose a method of extracting a folded, nonadiabatic, effective potential energy surface from electron nuclear dynamics (END) trajectories; we then perform nuclear wave packet...

  9. Investigation of Condensed Media in Weak Fields by the Method of Nuclear Magnetic Resonance

    Science.gov (United States)

    Davydov, V. V.; Myazin, N. S.; Dudkin, V. I.; Velichko, E. N.

    2018-05-01

    A compact design of a rapid-response nuclear magnetic spectrometer for investigation of condensed media in weak fields is reported. As a result of investigation of different condensed media, special features of recording a nuclear magnetic resonance (NMR) signal in a weak magnetic field from a small volume of the medium under study are established. For the first time the NMR absorption spectra of condensed media in a weak field are collected. Based on the results of experimental studies, the potential of using a compact NMR-spectrometer for condensed media monitoring in a rapid response mode is determined.

  10. Electric field confinement effect on charge transport in organic field-effect transistors

    NARCIS (Netherlands)

    Li, X.; Kadashchuk, A.; Fishchuk, I.I.; Smaal, W.T.T.; Gelinck, G.H.; Broer, D.J.; Genoe, J.; Heremans, P.; Bässler, H.

    2012-01-01

    While it is known that the charge-carrier mobility in organic semiconductors is only weakly dependent on the electric field at low fields, the experimental mobility in organic field-effect transistors using silylethynyl-substituted pentacene is found to be surprisingly field dependent at low

  11. Three-loop corrections in a covariant effective field theory

    International Nuclear Information System (INIS)

    McIntire, Jeff

    2008-01-01

    Chiral effective field theories have been used with success in the study of nuclear structure. It is of interest to systematically improve these energy functionals (particularly that of quantum hadrodynamics) through the inclusion of many-body correlations. One possible source of improvement is the loop expansion. Using the techniques of Infrared Regularization, the short-range, local dynamics at each order in the loops is absorbed into the parameterization of the underlying effective Lagrangian. The remaining nonlocal, exchange correlations must be calculated explicitly. Given that the interactions of quantum hadrodynamics are relatively soft, the loop expansion may be manageable or even perturbative in nuclear matter. This work investigates the role played by the three-loop contributions to the loop expansion for quantum hadrodynamics

  12. QCD Effective Field Theories for Heavy Quarkonium

    International Nuclear Information System (INIS)

    Brambilla, Nora

    2006-01-01

    QCD nonrelativistic effective field theories (NREFT) are the modern and most suitable frame to describe heavy quarkonium properties. Here I summarize few relevant concepts and some of the interesting physical applications (spectrum, decays, production) of NREFT

  13. Optically controlled locking of the nuclear field via coherent dark-state spectroscopy.

    Science.gov (United States)

    Xu, Xiaodong; Yao, Wang; Sun, Bo; Steel, Duncan G; Bracker, Allan S; Gammon, Daniel; Sham, L J

    2009-06-25

    A single electron or hole spin trapped inside a semiconductor quantum dot forms the foundation for many proposed quantum logic devices. In group III-V materials, the resonance and coherence between two ground states of the single spin are inevitably affected by the lattice nuclear spins through the hyperfine interaction, while the dynamics of the single spin also influence the nuclear environment. Recent efforts have been made to protect the coherence of spins in quantum dots by suppressing the nuclear spin fluctuations. However, coherent control of a single spin in a single dot with simultaneous suppression of the nuclear fluctuations has yet to be achieved. Here we report the suppression of nuclear field fluctuations in a singly charged quantum dot to well below the thermal value, as shown by an enhancement of the single electron spin dephasing time T(2)*, which we measure using coherent dark-state spectroscopy. The suppression of nuclear fluctuations is found to result from a hole-spin assisted dynamic nuclear spin polarization feedback process, where the stable value of the nuclear field is determined only by the laser frequencies at fixed laser powers. This nuclear field locking is further demonstrated in a three-laser measurement, indicating a possible enhancement of the electron spin T(2)* by a factor of several hundred. This is a simple and powerful method of enhancing the electron spin coherence time without use of 'spin echo'-type techniques. We expect that our results will enable the reproducible preparation of the nuclear spin environment for repetitive control and measurement of a single spin with minimal statistical broadening.

  14. Situation and role of industrial fields in nuclear fusion reactor development

    International Nuclear Information System (INIS)

    Suzuki, Gen-ichi

    1983-01-01

    Japan Atomic Industrial Forum (JAIF) established the nuclear fusion technical committee in October, 1980, and has investigated the attitude of industrial fields in progressing nuclear fusion research and development and the measures to cooperate with national development plans. Corresponding to the new long term plan and the establishment of the basic policy for nuclear fusion research and development by Atomic Energy Commission of Japan in June, 1982, JAIF has settled the policy on the situation and role of industrial fields. In this report, first the necessity of firmly grasping the position of nuclear fusion research in atomic energy development is described, next, the present status of the research and development in Japan is reported, and it is mentioned that the role of manufacturers in reinforcing engineering has become more important in industrial fields. In the stage of the construction of a nuclear fusion reactor, the experiences in the engineering safety in fission reactors, environmental safety and system engineering will be utilized. Japanese industrial fields feature that they have made larger cooperation with national projects even in the research and development stage as compared to foreign countries. When the plan of next phase system will be promoted in the future, the cooperating methods in the past should be evaluated, investigated and improved, and the experiences in fast breeder reactors and advanced heavy water reactors should be referred to. Finally, the problems and the countermeasures in nuclear fusion development are described. (Wakatsuki, Y.)

  15. Outline of results of safety research (in nuclear fuel cycle field in fiscal year 1996)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-01

    The safety research in Power Reactor and Nuclear Fuel Development Corporation in fiscal year 1996 has been carried out based on the basic plan of safety research (from fiscal year 1996 to 2000) which was decided in March, 1996. In this report, on nuclear fuel cycle field, namely all the subjects in the fields of nuclear fuel facilities, environmental radioactivity and waste disposal, and the subjects related to nuclear fuel facilities among the fields of aseismatic and probabilistic safety assessments, the results of research in fiscal year 1996, the first year of the 5-year project, are summarized together with the outline of the basic plan of safety research. The basic policy, objective and system for promotion of the safety research are described. The objectives of the safety research are the advancement of safety technology, the safety of facilities, stable operation techniques, the safety design and the evaluation techniques of next generation facilities, and the support of transferring nuclear fuel cycle to private businesses. The objects of the research are uranium enrichment, fuel fabrication and reprocessing, and waste treatment and storage. 52 investigation papers of the results of the safety research in nuclear fuel cycle field in fiscal year 1996 are collected in this report. (K.I.)

  16. Polarization effects in molecular mechanical force fields

    Energy Technology Data Exchange (ETDEWEB)

    Cieplak, Piotr [Burnham Institute for Medical Research, 10901 North Torrey Pines Road, La Jolla, CA 92120 (United States); Dupradeau, Francois-Yves [UMR CNRS 6219-Faculte de Pharmacie, Universite de Picardie Jules Verne, 1 rue des Louvels, F-80037 Amiens (France); Duan, Yong [Genome Center and Department of Applied Science, University of California, Davis, One Shields Avenue, Davis, CA 95616 (United States); Wang Junmei, E-mail: pcieplak@burnham.or [Department of Pharmacology, University of Texas Southwestern Medical Center, 6001 Forest Park Boulevard, ND9.136, Dallas, TX 75390-9050 (United States)

    2009-08-19

    The focus here is on incorporating electronic polarization into classical molecular mechanical force fields used for macromolecular simulations. First, we briefly examine currently used molecular mechanical force fields and the current status of intermolecular forces as viewed by quantum mechanical approaches. Next, we demonstrate how some components of quantum mechanical energy are effectively incorporated into classical molecular mechanical force fields. Finally, we assess the modeling methods of one such energy component-polarization energy-and present an overview of polarizable force fields and their current applications. Incorporating polarization effects into current force fields paves the way to developing potentially more accurate, though more complex, parameterizations that can be used for more realistic molecular simulations. (topical review)

  17. Considerations about decision processes in the nuclear field

    International Nuclear Information System (INIS)

    Borges, J.C.

    1986-01-01

    In all the countries of the world, official energy policies and programs are criticized by experts from the academic community and by the population at large. It is quite normal that people censure their government, but under the cloak of scientific arguments, one can usually find political objectives. The parameters which are an influence in this power game: up to what point can or should technocrats decide in the name of the people when and how can or should the people demonstrate their preference are presented. As this is a vast and polemic theme, and in order that some concrete conclusion could be drawn, we tried to concentrate our analysis on a specific case: the Brazilian decision to use nuclear energy. (Author) [pt

  18. Graphene Field Effect Transistor for Radiation Detection

    Science.gov (United States)

    Li, Mary J. (Inventor); Chen, Zhihong (Inventor)

    2016-01-01

    The present invention relates to a graphene field effect transistor-based radiation sensor for use in a variety of radiation detection applications, including manned spaceflight missions. The sensing mechanism of the radiation sensor is based on the high sensitivity of graphene in the local change of electric field that can result from the interaction of ionizing radiation with a gated undoped silicon absorber serving as the supporting substrate in the graphene field effect transistor. The radiation sensor has low power and high sensitivity, a flexible structure, and a wide temperature range, and can be used in a variety of applications, particularly in space missions for human exploration.

  19. Effective inventory management for nuclear power plants

    International Nuclear Information System (INIS)

    MacFarlane, I.S.

    1985-01-01

    Effective inventory management plays a major role at nuclear power plants toward achieving a high level of availability in a cost-effective manner. It enables maintenance personnel to obtain the correct parts easily, when needed, and in satisfactory condition to perform as intended. In addition, appropriate controls and documentation ensure parts are being used in the correct equipment application. The following elements of inventory management will help achieve plant availability goals: (1) appropriate inventory levels, (2) preapproved procurement requirements, (3) storage maintenance, (4) documentation of parts, and (5) control of computer data base

  20. Nuclear compression effects on pion production in nuclear collisions

    International Nuclear Information System (INIS)

    Sano, M.; Gyulassy, M.; Wakai, M.; Kitazoe, Y.

    1985-01-01

    We show that the method of analyzing the pion excitation function proposed by Stock et al. may determine only a part of the nuclear matter equation of state. With the addition of missing kinetic energy terms the implied high density nuclear equation of state would be much stiffer than expected from conventional theory. A stiff equation of state would also follow if shock dynamics with early chemical freeze out were valid. (orig.)

  1. Break up of light ions in the nuclear and Coulomb field of nuclei

    International Nuclear Information System (INIS)

    Srivastava, D.K.

    1985-12-01

    The break up of light ion projectiles in the nuclear and Coulomb field of nuclei is considered. Current theoretical concepts for describing break up processes and their theoretical features are discussed. An alternative method, based on a prior-interaction DWBA, is introduced for the calculation of the direct elastic break up cross sections. This method reveals the role of the internal momentum distribution of the break up fragments and includes corresponding 'finite range' effects. The Coulomb break up of 6 Li is studied on the basis of a quasi-sequential break up approach (following Rybicki and Austern) and results are obtained for very low relative energies of the emerging α-particles and deuteron fragments. The astrophysical interest in these cross sections is noted. A view on further extensions of the break up theory is given. (orig.) [de

  2. Pressure fluctuation characteristics of flow field of mixed flow nuclear primary pump

    International Nuclear Information System (INIS)

    Wang Chunlin; Yang Xiaoyong; Li Changjun; Jia Fei; Zhao Binjuan

    2013-01-01

    In order to research the pressure fluctuation characteristics of flow field of mixed flow nuclear primary pump, this study used the technique of ANSYS-Workbench and CFX fluid solid heat coupling to do numerical simulation analysis for model pump. According to the situation of pressure fluctuation of time domain and frequency domain, the main cause of pressure fluctuation was discussed. For different flow, the pressure fluctuations were compared. This study shows it is feasible that large eddy simulation method is used for the research of pressure fluctuation. The pressure fluctuation amplitudes of four sections are increasing from wheel hub to wheel rim. The pressure fluctuation of inlet and outlet of impeller depends on the rotational frequency of impeller. Along with the fluid flowing away from the impeller, the effect of the impeller on the fluid pressure fluctuation weakens gradually. Comparing the different results of three flow conditions, the pressure fluctuation in design condition flow is superior to the others. (authors)

  3. Introduction to workshop on radiation effects in nuclear waste materials

    International Nuclear Information System (INIS)

    Matzke, H.

    1988-01-01

    The workshop consisted of an invited lecture for REI-4, treating radiation damage in nuclear fuels as well as giving an introduction to the field of damage in waste matrices, of invited and contributed lectures to the workshop and to REI as well as of discussions and round table meetings. The contributions available as manuscripts are included on the following pages of these proceedings. At the end, a short summary with recommendations for future work has been added. It is hoped that the stimulating discussions of the workshop will help to continue the work in the field of radiation effects in waste matrices in an effective way. The organizer believes that there are good reasons for this hope and he thanks all scientists who contributed to the success of the workshop, as well as members of the organizing committee of REI-4 for their help. (orig.)

  4. Field emission current from a junction field-effect transistor

    Energy Technology Data Exchange (ETDEWEB)

    Monshipouri, Mahta; Abdi, Yaser, E-mail: y.abdi@ut.ac.ir [University of Tehran, Nano-Physics Research Laboratory, Department of Physics (Iran, Islamic Republic of)

    2015-04-15

    Fabrication of a titanium dioxide/carbon nanotube (TiO{sub 2}/CNT)-based transistor is reported. The transistor can be considered as a combination of a field emission transistor and a junction field-effect transistor. Using direct current plasma-enhanced chemical vapor deposition (DC-PECVD) technique, CNTs were grown on a p-typed (100)-oriented silicon substrate. The CNTs were then covered by TiO{sub 2} nanoparticles 2–5 nm in size, using an atmospheric pressure CVD technique. In this device, TiO{sub 2}/CNT junction is responsible for controlling the emission current. High on/off-current ratio and proper gate control are the most important advantages of device. A model based on Fowler–Nordheim equation is utilized for calculation of the emission current and the results are compared with experimental data. The effect of TiO{sub 2}/CNT hetero-structure is also investigated, and well modeled.

  5. An Unusual Partnership: Brazilian-Italian Forms of Cooperation in the Nuclear Field (1951-1986)

    International Nuclear Information System (INIS)

    Patti, Carlo

    2017-01-01

    This chapter discusses the Brazilian-Italian cooperation in the nuclear field between the early 1950s and 1986. Since the late 1930s, Italian or Italian-Brazilian scientists promoted the development of studies in nuclear physics. Immediately after World War II, the Brazilian-Italian collaboration continued. Between the 1950s and the 1970s, Brazilian nuclear scientists studied in Italian institutions. Relying on primary sources from Brazilian archives and oral history interviews with protagonists of the Brazilian nuclear program, this chapter explore the relations between Italy and Brazil from 1951, the year of the establishment of the Brazilian nuclear program, until the 1980s. This study focuses on the bidirectional transfer of knowledge on sensitive technologies, and on the formal and informal cooperation between the two countries.

  6. Programme of basic nuclear research and associated fields 1977-1981

    International Nuclear Information System (INIS)

    1978-01-01

    Nuclear research and development have been intensively pursued in West Germany by the Government and the Laender since 1955. In this period, the aims and official measures for fostering the research and use of nuclear power for peaceful purposes were laid down in four nuclear programmes. The 4th Nuclear Programme covers the period 1973 to 1976. From 1977, nuclear development became part of the energy research programme which was published by the West German Government in the spring of 1977. The basic nuclear research, however, was regarded as part of a total concept for fostering basic research (to be developed). While all the activities of research in the natural sciences and arts fostered by the West German Ministry of Research and Technology were to be co-ordinated in a more schematic form in the plan for 'Basic Research', it is the aim of the present statement to take stock of the present situation in 'Basic Nuclear Research' including the associated fields of 'Nuclear Solid Research' and 'Synchrotron Radiation', to analyse their structure, to describe the scientific aims for the next five years and to determine the total financial requirements. The basis for determining the financial programme worked out by the expert committee on 'Physical Research in the Nuclear Field' and the other committees in this field. The plans are in agreement with the medium term plan of the West German Ministry of Research and Technology (at 27.10.1977) and their contents correspond to the state of affairs at the end of 1977. (orig./UA) [de

  7. A description of a wide beam saddle field ion source used for nuclear target applications

    International Nuclear Information System (INIS)

    Greene, J.P.; Schiel, S.L.; Thomas, G.E.

    1997-01-01

    A description is given of a new, wide beam saddle field sputter source used for the preparation of targets applied in nuclear physics experiments. The ion source characteristics are presented and compared with published results obtained with other sources. Deposition rates acquired utilizing this source are given for a variety of target materials encountered in nuclear target production. New applications involving target thinning and ion milling are discussed

  8. Nuclear excitation via the motion of electrons in a strong laser field

    International Nuclear Information System (INIS)

    Berger, J.F.; Gogny, D.; Weiss, M.S.

    1987-12-01

    A method of switching from a nuclear isomeric state to a lasing state is examined. A semi-classical model of laser-electron-nuclear coupling is developed. In it the electrons are treated as free in the external field of the laser, but with initial conditions corresponding to their atomic orbits. Application is made to testing this model in 235 U and to the design criteria of a gamma-ray laser. 14 refs., 2 tabs

  9. Nuclear proliferomics: A new field of study to identify signatures of nuclear materials as demonstrated on alpha-UO3.

    Science.gov (United States)

    Schwerdt, Ian J; Brenkmann, Alexandria; Martinson, Sean; Albrecht, Brent D; Heffernan, Sean; Klosterman, Michael R; Kirkham, Trenton; Tasdizen, Tolga; McDonald Iv, Luther W

    2018-08-15

    The use of a limited set of signatures in nuclear forensics and nuclear safeguards may reduce the discriminating power for identifying unknown nuclear materials, or for verifying processing at existing facilities. Nuclear proliferomics is a proposed new field of study that advocates for the acquisition of large databases of nuclear material properties from a variety of analytical techniques. As demonstrated on a common uranium trioxide polymorph, α-UO 3 , in this paper, nuclear proliferomics increases the ability to improve confidence in identifying the processing history of nuclear materials. Specifically, α-UO 3 was investigated from the calcination of unwashed uranyl peroxide at 350, 400, 450, 500, and 550 °C in air. Scanning electron microscopy (SEM) images were acquired of the surface morphology, and distinct qualitative differences are presented between unwashed and washed uranyl peroxide, as well as the calcination products from the unwashed uranyl peroxide at the investigated temperatures. Differential scanning calorimetry (DSC), UV-Vis spectrophotometry, powder X-ray diffraction (p-XRD), and thermogravimetric analysis-mass spectrometry (TGA-MS) were used to understand the source of these morphological differences as a function of calcination temperature. Additionally, the SEM images were manually segmented using Morphological Analysis for MAterials (MAMA) software to identify quantifiable differences in morphology for three different surface features present on the unwashed uranyl peroxide calcination products. No single quantifiable signature was sufficient to discern all calcination temperatures with a high degree of confidence; therefore, advanced statistical analysis was performed to allow the combination of a number of quantitative signatures, with their associated uncertainties, to allow for complete discernment by calcination history. Furthermore, machine learning was applied to the acquired SEM images to demonstrate automated discernment with

  10. Visualization system for grid environment in the nuclear field

    International Nuclear Information System (INIS)

    Suzuki, Yoshio; Matsumoto, Nobuko; Idomura, Yasuhiro; Tani, Masayuki

    2006-01-01

    An innovative scientific visualization system is needed to integratedly visualize large amount of data which are distributedly generated in remote locations as a result of a large-scale numerical simulation using a grid environment. One of the important functions in such a visualization system is a parallel visualization which enables to visualize data using multiple CPUs of a supercomputer. The other is a distributed visualization which enables to execute visualization processes using a local client computer and remote computers. We have developed a toolkit including these functions in cooperation with the commercial visualization software AVS/Express, called Parallel Support Toolkit (PST). PST can execute visualization processes with three kinds of parallelism (data parallelism, task parallelism and pipeline parallelism) using local and remote computers. We have evaluated PST for large amount of data generated by a nuclear fusion simulation. Here, two supercomputers Altix3700Bx2 and Prism installed in JAEA are used. From the evaluation, it can be seen that PST has a potential to efficiently visualize large amount of data in a grid environment. (author)

  11. Nuclear Winter: Uncertainties Surround the Long-Term Effects of Nuclear War. Report to the Congress.

    Science.gov (United States)

    General Accounting Office, Washington, DC.

    Nuclear winter, a term used to describe potential long-term climate and environmental effects of nuclear war, has been a subject of debate and controversy. This report examines and presents scientific and policy implications of nuclear winter. Contents include: (1) an executive summary (highlighting previous and current studies on the topic); (2)…

  12. Direct coupled amplifiers using field effect transistors

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, E P [Control and Instrumentation Division, Atomic Energy Establishment, Winfrith, Dorchester, Dorset (United Kingdom)

    1964-03-15

    The concept of the uni-polar field effect transistor (P.E.T.) was known before the invention of the bi-polar transistor but it is only recently that they have been made commercially. Being produced as yet only in small quantities, their price imposes a restriction on use to circuits where their peculiar properties can be exploited to the full. One such application is described here where the combination of low voltage drift and relatively low input leakage current are necessarily used together. One of the instruments used to control nuclear reactors has a logarithmic response to the mean output current from a polarised ionisation chamber. The logarithmic signal is then differentiated electrically, the result being displayed on a meter calibrated to show the reactor divergence or doubling time. If displayed in doubling time the scale is calibrated reciprocally. Because of the wide range obtained in the logarithmic section and the limited supply voltage, an output of 1 volt per decade change in ionisation current is used. Differentiating this gives a current of 1.5 x 10{sup -8} A for p.s.D. (20 sec. doubling time) in the differentiating amplifier. To overcome some of the problems of noise due to statistical variations in input current, the circuit design necessitates a resistive path to ground at the amplifier input of 20 M.ohms. A schematic diagram is shown. 1. It is evident that a zero drift of 1% can be caused by a leakage current of 1.5 x 10{sup -10} A or an offset voltage of 3 mV at the amplifier input. Although the presently used electrometer valve is satisfactory from the point of view of grid current, there have been sudden changes in grid to grid voltage (the valve is a double triode) of up to 10 m.V. It has been found that a pair of F.E.T's. can be used to replace the electrometer valve so long as care is taken in correct balance of the two devices. An investigation has been made into the characteristics of some fourteen devices to see whether those with

  13. Potential effects of nuclear war on agricultural productivity

    International Nuclear Information System (INIS)

    Harwell, M.A.; Cropper, W.P. Jr.

    1985-01-01

    The authors examine the vulnerabilities of agricultural systems to nuclear war-induced climatic perturbations and to other, indirect effects of nuclear war. Discussion is included of the dependency of agricultural production on technological inputs and the effects of loss or reduction of these inputs in a post-nuclear war world

  14. Present status and needs of human resource development in nuclear field in Korea

    International Nuclear Information System (INIS)

    Choi, Young-Myung; Lee, Eui-Jin

    2000-01-01

    The Nuclear Training Center (NTC) of KAERI (Korea Atomic Energy Research Institute) began training technical personnel in the field of radioisotope utilization and radiation protection during the 1960's. During the first stage of the nation's nuclear power project in the 1970's, the main effort of the Center focused on training those in nuclear power and nuclear engineering. During a stage of increased technical self-reliance in the 1980's, the Center extended its training role to implement more specific training courses on nuclear power and safety fields. Since 1983, the Center has been empowered at the request of government to provide retraining courses for nuclear-related license holders and qualified engineers. The Center has offered IAEA regional training course annually for Asia and Pacific region member states since 1988. Since 1967, the total number of trainees is up to 27,777 as of the end of 1998. KEPCO (Korea Electric Power Corporation) started Nuclear Power Education Center (NPEC) in 1990. The outlines of KEPCO's in-house training programs are presented in the report. The reactor operators, and the persons engaged in nuclear fuel materials, radioisotope or radiation generating devices need particular licenses in accordance with Korean Atomic Energy Laws and Regulation. NTC/KAERI and NPEC/KEPCO should report annual retraining programs for licensed personnel to Ministry Of Science and Technology (MOST) every year. The outlines of projects, which are directly related to human resources development in nuclear field in Korea, are described in the paper. The International Atomic Energy Agency (IAEA) has made efforts to provide training programs for technical personnel of developing countries for the peaceful uses of nuclear energy. Korea has also received lots of assistance for her manpower development from the Agency. Korea is now on the verge of transforming herself from a technology recipient country in some practical and fundamental fields. The

  15. Present status and needs of human resource development in nuclear field in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Young-Myung; Lee, Eui-Jin [Nuclear Training Center, Korea Atomic Energy Research Institute, Taejon (Korea)

    2000-12-01

    The Nuclear Training Center (NTC) of KAERI (Korea Atomic Energy Research Institute) began training technical personnel in the field of radioisotope utilization and radiation protection during the 1960's. During the first stage of the nation's nuclear power project in the 1970's, the main effort of the Center focused on training those in nuclear power and nuclear engineering. During a stage of increased technical self-reliance in the 1980's, the Center extended its training role to implement more specific training courses on nuclear power and safety fields. Since 1983, the Center has been empowered at the request of government to provide retraining courses for nuclear-related license holders and qualified engineers. The Center has offered IAEA regional training course annually for Asia and Pacific region member states since 1988. Since 1967, the total number of trainees is up to 27,777 as of the end of 1998. KEPCO (Korea Electric Power Corporation) started Nuclear Power Education Center (NPEC) in 1990. The outlines of KEPCO's in-house training programs are presented in the report. The reactor operators, and the persons engaged in nuclear fuel materials, radioisotope or radiation generating devices need particular licenses in accordance with Korean Atomic Energy Laws and Regulation. NTC/KAERI and NPEC/KEPCO should report annual retraining programs for licensed personnel to Ministry Of Science and Technology (MOST) every year. The outlines of projects, which are directly related to human resources development in nuclear field in Korea, are described in the paper. The International Atomic Energy Agency (IAEA) has made efforts to provide training programs for technical personnel of developing countries for the peaceful uses of nuclear energy. Korea has also received lots of assistance for her manpower development from the Agency. Korea is now on the verge of transforming herself from a technology recipient country in some practical and

  16. International co-operation in the nuclear field. Europe and OCDE countries

    International Nuclear Information System (INIS)

    Strohl, P.

    1981-05-01

    This report highlights the political factors underlying nuclear cooperation in the European context. It analyses the institutional structure for such cooperation and describes the different vocations of international organisations in the nuclear field (NEA, IAEA, Euratom). Finally the report gives concrete examples of international nuclear cooperation, with an emphasis on its legal aspects. (NEA) []Le present expose fait ressortir les facteurs politiques de la cooperation nucleaire notamment dans le contexte europeen. Il analyse la structure institutionnelle de cette cooperation et evoque les differentes vocations des organismes internationaux dans le domaine nucleaire (AEN, AIEA, Euratom). Il donne enfin des exemples concrets en mettant l'accent sur ses aspects juridiques

  17. Study of the Brazilian scientific production in the nuclear field from 1970 to 1979

    International Nuclear Information System (INIS)

    Nascimento, M. de J.

    1983-01-01

    The study of some patterns of the Brazilian scientific literature production - e.g., generated and/or published in Brazil - in the nuclear field included in CIN (Nuclear Information Center) / INIS (International Nuclear Information System) data base from 1970 to 1979 is presented. The purpose is to research: - the growth of the production; - the main subject areas; - the language of the publication; - the literature presentation form; - the author's characterization; - the most productive institutions, their geographical distribution and countries where the literature is published. (E.G.) [pt

  18. Nuclear energy 1986: Again in the field of tension of politics

    International Nuclear Information System (INIS)

    Broeders, I.; Wiese, H.W.; Karwat, H.; Schmitter, K.H.; Buchholz, H.; Thamm, G.; Hollmann, H.; Kalkoffen, F.

    1986-01-01

    The 1986 Jahrestagung Kerntechnik was held from April 8 to 10. The report first summarises the principal division lectures and the conference programme, and continues with brief accounts of various papers presented to the following divisions: 1) Reactor physics; 2) Thermodynamics and fluid dynamics; 3) Nuclear installations safety; 4) Fuel cycle and nuclear waste management; 5) Fuel elements and fuel materials; 6) Components and materials, quality assurance; 7) Construction and operation of nuclear installations; 8a) Fusion technology, 8b) Research and test reactors; 9) Energy systems and the power industry; 10) Atomic Energy Law, radiation protection and the Law on Environmental Protection Against Obnoxious Substances and related fields of law. (UA) [de

  19. Multiconfigurational self-consistent field calculations of nuclear shieldings using London atomic orbitals

    DEFF Research Database (Denmark)

    Ruud, Kenneth; Helgaker, Trygve; Kobayashi, Rika

    1994-01-01

    to corresponding individual gauges for localized orbitals (IGLO) results. The London results show better basis set convergence than IGLO, especially for heavier atoms. It is shown that the choice of active space is crucial for determination of accurate nuclear shielding constants.......Nuclear shielding calculations are presented for multiconfigurational self-consistent field wave functions using London atomic orbitals (gauge invariant atomic orbitals). Calculations of nuclear shieldings for eight molecules (H2O, H2S, CH4, N2, CO, HF, F2, and SO2) are presented and compared...

  20. States and tendencies of German standards in the field of nuclear filter technology

    International Nuclear Information System (INIS)

    Fichtner, N.; Sinhuber, D.

    1977-01-01

    The current situation in the Federal Republic of Germany with regard to standards and guidelines in the field of filter technology, as they apply to nuclear technology, is first presented. A detailed discussion follows of the results arrived at by the Nuclear Technology Standards Committee in its deliberations on the Standards' project DIN 25 414 'Ventilation equipment in nuclear power stations'. Particular attention is paid to the technical safety requirements for particulate filters, filter casings and filter housings, and methods of testing. The results so far obtained as regards filters in ventilation plant for pressurized water reactors are also dealt with

  1. Soil–structure interaction analyses to locate nuclear power plant free-field seismic instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, James J., E-mail: jasjjoh@aol.com [James J. Johnson and Associates, Alamo, CA (United States); Ake, Jon P. [US Nuclear Regulatory Commission, Washington, DC (United States); Maslenikov, Oleg R. [James J. Johnson and Associates, Alamo, CA (United States); Kenneally, Roger M. [Consultant, Seminole, FL (United States)

    2015-12-15

    Highlights: • Determine the location of seismic instrumentation so that recorded motion will be free-field motion. • Certified Designs of nuclear island for AP1000 and EPR; ABWR Reactor Building were analyzed. • Three site conditions and multiple recorded time histories were considered. • Instrumentation located 1-diameter from the edge of structure/foundation is adequate. • Acceptance criteria were probability of non-exceedance of response spectra values. - Abstract: The recorded earthquake ground motion at the nuclear power plant site is needed for several purposes. US Nuclear Regulatory Commission (NRC) Regulatory Guide 1.12, Nuclear Power Plant Instrumentation for Earthquakes, NRC (1997a), describes acceptable instrumentation to meet the requirements in NRC's regulations pertaining to earthquake engineering criteria for nuclear power plants. The ground motion data recorded by the free-field seismic instrumentation are used to compare the actual earthquake motion at the site with the design input motion. The result of the comparison determines if the Operating Basis Earthquake ground motion (OBE) has been exceeded and plant shutdown is required per the guidance in NRC Regulatory Guide 1.166, Pre-Earthquake Planning and Immediate Nuclear Power Plant Operator Postearthquake Actions, NRC (1979b). The free-field is defined as a location on the ground surface or in the site soil column that is sufficiently distant from the site structures to be essentially unaffected by the vibration of the site structures.

  2. Unified description of structure and reactions: implementing the nuclear field theory program

    International Nuclear Information System (INIS)

    Broglia, R A; Bortignon, P F; Barranco, F; Vigezzi, E; Idini, A; Potel, G

    2016-01-01

    The modern theory of the atomic nucleus results from the merging of the liquid drop model of Niels Bohr and Fritz Kalckar, and of the shell model of Marie Goeppert Meyer and Hans Jensen. The first model contributed the concepts of collective excitations. The second, those of independent-particle motion. The unification of these apparently contradictory views in terms of the particle-vibration and particle-rotation couplings carried out by Aage Bohr and Ben Mottelson has allowed for an ever more complete, accurate and detailed description of nuclear structure. Nuclear field theory (NFT), developed by the Copenhagen–Buenos Aires collaboration, provided a powerful quantal embodiment of this unification. Reactions are not only at the basis of quantum mechanics (statistical interpretation, Max Born), but also the specific tools to probe the atomic nucleus. It is then natural that NFT is being extended to deal with processes which involve the continuum in an intrinsic fashion, so as to be able to treat them on an equal footing with those associated with bound states (structure). As a result, spectroscopic studies of transfer to continuum states could eventually make use of the NFT rules, properly extended to take care of recoil effects. In the present contribution we review the implementation of the NFT program of structure and reactions, setting special emphasis on open problems and outstanding predictions. (invited comment)

  3. Simulation mechanisms of low energy nuclear reaction using super flow energy external fields

    International Nuclear Information System (INIS)

    Gareev, F.A.; Zhidkova, I.E.; ); Ratis, Yu.I.

    2005-01-01

    Full text: The review of possible stimulation mechanisms of the LENR (low energy nuclear reactions) is represented. We have concluded that transamination of nuclei at low energies and excess heat are possible in the framework of the modern physical theory - the universal resonance synchronization principle and based on its different enhancement mechanisms of reaction rates are responsible for these processes. The excitation nd ionization of atom may play role as trigger for LERN. Investigation of this phenomenon requires knowledge of different branches if science: nuclear and atomic physics, chemistry and electrochemistry, condensed matter and solid state physics. The results of this research field can provide a new source of energy, substances and technologies. The puzzle of poor re-productivity of experimental data in due ti the fact LENR occurs in open systems and it is extremely sensitive to parameters of external fields and systems. Classical re-productivity principle should be reconsidered for LENR experiments. Poor re-productivity and unexpected results do not means that the experiment is wrong. Our main conclusion: LENR may be understand in terms of the modern theory without any violation of the basic physics. 2) Weak and electromagnetic interactions may show the strong influence of the surrounding conditions on the nuclear processes. 3) Universal resonance synchronization principle is a key issue to make a bridge between various scales of interactions and it is responsible for self-organization of hierarchical systems independent of substances, fields and interactions. We bring some arguments in favor of the mechanism - order based on order - declared by Schroedinger in fundamental problem of contemporary science. 4) The universal resonance synchronization principle became a fruitful interdisciplinary science of general laws of self-organized processes in different branches of physics because it is consequence of the energy conservation law and resonance

  4. Magnetic field effects on electrochemical metal depositions

    Directory of Open Access Journals (Sweden)

    Andreas Bund, Adriana Ispas and Gerd Mutschke

    2008-01-01

    Full Text Available This paper discusses recent experimental and numerical results from the authors' labs on the effects of moderate magnetic (B fields in electrochemical reactions. The probably best understood effect of B fields during electrochemical reactions is the magnetohydrodynamic (MHD effect. In the majority of cases it manifests itself in increased mass transport rates which are a direct consequence of Lorentz forces in the bulk of the electrolyte. This enhanced mass transport can directly affect the electrocrystallization. The partial currents for the nucleation of nickel in magnetic fields were determined using an in situ micro-gravimetric technique and are discussed on the basis of the nucleation model of Heerman and Tarallo. Another focus of the paper is the numerical simulation of MHD effects on electrochemical metal depositions. A careful analysis of the governing equations shows that many MHD problems must be treated in a 3D geometry. In most cases there is a complex interplay of natural and magnetically driven convection.

  5. Effective lagrangian from bosonic string field theory

    International Nuclear Information System (INIS)

    Nakazawa, Naohito

    1987-01-01

    We investigate the low-energy effective action from the string field theoretical view point. The low-energy effective lagrangian for the massless mode of bosonic string is determined to the order of α'. We find a term which can not be determined from the S-matrix approach. (author)

  6. Effective field equations for expectation values

    International Nuclear Information System (INIS)

    Jordan, R.D.

    1986-01-01

    We discuss functional methods which allow calculation of expectation values, rather than the usual in-out amplitudes, from a path integral. The technique, based on Schwinger's idea of summing over paths which go from the past to the future and then back to the past, provides effective field equations satisfied by the expectation value of the field. These equations are shown to be real and causal for a general theory up to two-loop order, and unitarity is checked to this order. These methods are applied to a simple quantum-mechanical example to illustrate the differences between the new formalism and the standard theory. When applied to the gravitational field, the new effective field equations should be useful for studies of quantum cosmology

  7. Status of effective field theory of NN scattering

    International Nuclear Information System (INIS)

    Beane, S.R.

    1998-06-01

    There exist many nucleon-nucleon potentials which reproduce phase shifts and nuclear properties with remarkable accuracy. Three fundamental features are shared by these potential models: (1) pions are important at long distances, (2) there is a source of intermediate-range attraction, and (3) there is a source of short-distance repulsion. However, in general, distinct physical mechanisms in these models account for the same feature of the nuclear force. Agreement with experiment is maintained in spite of these differences because of the large number of fit parameters. Systematic approaches to the scattering of strongly interacting particles, such as chiral perturbation theory, are based on the ideas of effective field theory (EFT). The author reviews recent progress in developing a systematic power counting scheme for scattering processes involving more than one nucleon

  8. Strengthening of the nuclear safety regulatory body. Field evaluation review

    International Nuclear Information System (INIS)

    1996-10-01

    As a result of a request from the Preparation Committee of the Nuclear Regulatory Authority (NRA) in 1992, and as recommended by the CEC/RAMG (Commission of European Communities/Regulatory Assistance Management Group) and the Agency mission in July 1993 to the Slovak Republic, the project SLR/9/005 was approved in 1993 as a model project for the period 1994-1996. Current budge is $401,340 and disbursements to date amount to $312,873. The project time schedule has been extended to 1997. The major conclusions of this evaluation are as follows: The project responded to an urgent national need, as well as to a statutory mandate of the Agency, and was adequately co-ordinated with other international assistance programmes to NRA. The project was designed as a structured programme of assistance by means of expert missions, scientific visits and a limited amount of equipment, acting upon several key areas of NRA regulatory responsibilities. Agency assistance was provided in a timely manner. A high concentration of expert missions was noticed at the initial stages of the project, which posed some managements problems. This was corrected to some extent in the course of implementation. Additionally, some overlapping of expert mission recommendations suggests that improvements are needed in the design of such missions. The exposure to international regulatory practice and expertise has resulted in substantial developments of NRA, both in organizational and operational terms. The project can claim to have contributed to NRA having gained governmental and international confidence. NRA's role in the safety assessment of Bohunice V1 reconstruction, as well as in Bohunice V2 safety review, Bohunice A1 decommissioning and in informing the public, also points at the success achieved by the project. The institutional and financial support of the Government contributed decisively to the project achievements. (author). Figs, tabs

  9. High-field Overhauser dynamic nuclear polarization in silicon below the metal-insulator transition.

    Science.gov (United States)

    Dementyev, Anatoly E; Cory, David G; Ramanathan, Chandrasekhar

    2011-04-21

    Single crystal silicon is an excellent system to explore dynamic nuclear polarization (DNP), as it exhibits a continuum of properties from metallic to insulating as a function of doping concentration and temperature. At low doping concentrations DNP has been observed to occur via the solid effect, while at very high-doping concentrations an Overhauser mechanism is responsible. Here we report the hyperpolarization of (29)Si in n-doped silicon crystals, with doping concentrations in the range of (1-3) × 10(17) cm(-3). In this regime exchange interactions between donors become extremely important. The sign of the enhancement in our experiments and its frequency dependence suggest that the (29)Si spins are directly polarized by donor electrons via an Overhauser mechanism within exchange-coupled donor clusters. The exchange interaction between donors only needs to be larger than the silicon hyperfine interaction (typically much smaller than the donor hyperfine coupling) to enable this Overhauser mechanism. Nuclear polarization enhancement is observed for a range of donor clusters in which the exchange energy is comparable to the donor hyperfine interaction. The DNP dynamics are characterized by a single exponential time constant that depends on the microwave power, indicating that the Overhauser mechanism is a rate-limiting step. Since only about 2% of the silicon nuclei are located within 1 Bohr radius of the donor electron, nuclear spin diffusion is important in transferring the polarization to all the spins. However, the spin-diffusion time is much shorter than the Overhauser time due to the relatively weak silicon hyperfine coupling strength. In a 2.35 T magnetic field at 1.1 K, we observed a DNP enhancement of 244 ± 84 resulting in a silicon polarization of 10.4 ± 3.4% following 2 h of microwave irradiation.

  10. Quality assurance in the field of nuclear power, international and Romanian practice

    International Nuclear Information System (INIS)

    Rogociu, Ioan

    1997-01-01

    Electricity should be generated in nuclear power plants under nuclear safety regulations with a high reliability level. In order to achieve this requirement it is necessary to work under quality assurance (QA) mode. The term of 'quality assurance' was used for the first time in USA in 1967. Since then, the situation has continuously developed. The most comprehensive standards in the fields are the USA ones. The IAEA agency in Vienna developed the first standards in 1978. The developed countries have their own legislation in the field. The IAEA standards, are based on the USA, German, Japanese, British, Canadian and French legislation. Romania drafted the Law No. 6/1982, repealed by the Law No. 11 in 1996. There is no satisfactory Romanian standard at present to regulate the activities of quality assurance in the nuclear power field. The works at Unit 1 of Cernavoda nuclear power plant were performed under the Canadian QA standards. The Canadian nuclear power company Ontario Hydro has been lately confronted with difficulties that may lead to decommission of 7 out of 19 units now in operation. To avoid the Canadian system deficiencies Romania needs standards based on the experience gained in this field by all developed countries, such as: USA, Japan, Germany, France, etc and IAEA regulations. The present paper is a pleading in favour of the Romanian legislation drafting at the level of the international demands. (author)

  11. Dynamically assisted Sauter-Schwinger effect in inhomogeneous electric fields

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Christian; Schützhold, Ralf [Fakultät für Physik, Universität Duisburg-Essen,Lotharstrasse 1, 47057 Duisburg (Germany)

    2016-02-24

    Via the world-line instanton method, we study electron-positron pair creation by a strong (but sub-critical) electric field of the profile E/cosh{sup 2} (kx) superimposed by a weaker pulse E{sup ′}/cosh{sup 2} (ωt). If the temporal Keldysh parameter γ{sub ω}=mω/(qE) exceeds a threshold value γ{sub ω}{sup crit} which depends on the spatial Keldysh parameter γ{sub k}=mk/(qE), we find a drastic enhancement of the pair creation probability — reporting on what we believe to be the first analytic non-perturbative result for the interplay between temporal and spatial field dependences E(t,x) in the Sauter-Schwinger effect. Finally, we speculate whether an analogous effect (drastic enhancement of tunneling probability) could occur in other scenarios such as stimulated nuclear decay, for example.

  12. Artificial intelligence applications in the nuclear field: Achievements and prospects: The new challenge

    International Nuclear Information System (INIS)

    Thomas, J.B.

    1993-01-01

    The first applications of Artificial Intelligence in the nuclear field were expert systems dedicated to off-line problems of diagnosis and maintenance. A second step aimed at solving more ambitious problems related to plant design and operation, which improved methodologies and tools. By the end of this period, new limits appeared. To solve the problems faced in the late eighties, powerful principles and methods became available. These require extensive sources. The present book describes examples of large-scale applications of Artificial Intelligence in the nuclear field

  13. Optical-coupling nuclear spin maser under highly stabilized low static field

    Energy Technology Data Exchange (ETDEWEB)

    Yoshimi, A., E-mail: yoshimi@ribf.riken.jp [RIKEN Nishina Center (Japan); Inoue, T.; Uchida, M.; Hatakeyama, N.; Asahi, K. [Tokyo Institute of Technology, Department of Physics (Japan)

    2008-01-15

    A nuclear spin maser of a new type, that employs a feedback scheme based on optical nuclear spin detection, has been fabricated. The spin maser is operated at a low static field of 30 mG by using the optical detection method. The frequency stability and precision of the spin maser have been improved by a highly stabilized current source for the static magnetic field. An experimental setup to search for an electric dipole moment (EDM) in {sup 129}Xe atom is being developed.

  14. On the field determination of effective porosity

    International Nuclear Information System (INIS)

    Javandel, I.

    1989-03-01

    Effective porosity of geologic materials is a very important parameter for estimating groundwater travel time and modeling contaminant transport in hydrologic systems. Determination of a representative effective porosity for nonideal systems is a problem still challenging hydrogeologists. In this paper, some of the conventional field geophysical and hydrological methods for estimating effective porosity of geologic materials are reviewed. The limitations and uncertainties associated with each method are discussed. 30 refs., 8 figs

  15. Effective field theory for triaxially deformed nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Q.B. [Technische Universitaet Muechen, Physik-Department, Garching (Germany); Peking University, State Key Laboratory of Nuclear Physics and Technology, School of Physics, Beijing (China); Kaiser, N. [Technische Universitaet Muechen, Physik-Department, Garching (Germany); Meissner, Ulf G. [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Bonn (Germany); Institute for Advanced Simulation, Institut fuer Kernphysik, Juelich Center for Hadron Physics and JARA-HPC, Forschungszentrum Juelich, Juelich (Germany); Meng, J. [Peking University, State Key Laboratory of Nuclear Physics and Technology, School of Physics, Beijing (China); Beihang University, School of Physics and Nuclear Energy Engineering, Beijing (China); University of Stellenbosch, Department of Physics, Stellenbosch (South Africa)

    2017-10-15

    Effective field theory is generalized to investigate the rotational motion of triaxially deformed even-even nuclei. The Hamiltonian for the triaxial rotor is obtained up to next-to-leading order within the effective field theory formalism. Its applicability is examined by comparing with a five-dimensional rotor-vibrator Hamiltonian for the description of the energy spectra of the ground state and γ band in Ru isotopes. It is found that by taking into account the next-to-leading order corrections, the ground state band in the whole spin region and the γ band in the low spin region are well described. The deviations for high-spin states in the γ bands point towards the importance of including vibrational degrees of freedom in the effective field theory formulation. (orig.)

  16. Effective field theory and the quark model

    International Nuclear Information System (INIS)

    Durand, Loyal; Ha, Phuoc; Jaczko, Gregory

    2001-01-01

    We analyze the connections between the quark model (QM) and the description of hadrons in the low-momentum limit of heavy-baryon effective field theory in QCD. By using a three-flavor-index representation for the effective baryon fields, we show that the 'nonrelativistic' constituent QM for baryon masses and moments is completely equivalent through O(m s ) to a parametrization of the relativistic field theory in a general spin-flavor basis. The flavor and spin variables can be identified with those of effective valence quarks. Conversely, the spin-flavor description clarifies the structure and dynamical interpretation of the chiral expansion in effective field theory, and provides a direct connection between the field theory and the semirelativistic models for hadrons used in successful dynamical calculations. This allows dynamical information to be incorporated directly into the chiral expansion. We find, for example, that the striking success of the additive QM for baryon magnetic moments is a consequence of the relative smallness of the non-additive spin-dependent corrections

  17. Ductal carcinoma in situ of the breast (DCIS with heterogeneity of nuclear grade: prognostic effects of quantitative nuclear assessment

    Directory of Open Access Journals (Sweden)

    Fu Yuejiao

    2007-09-01

    Full Text Available Abstract Background Previously, 50% of patients with breast ductal carcinoma in situ (DCIS had more than one nuclear grade, and neither worst nor predominant nuclear grade was significantly associated with development of invasive carcinoma. Here, we used image analysis in addition to histologic evaluation to determine if quantification of nuclear features could provide additional prognostic information and hence impact prognostic assessments. Methods Nuclear image features were extracted from about 200 nuclei of each of 80 patients with DCIS who underwent lumpectomy alone, and received no adjuvant systemic therapy. Nuclear images were obtained from 20 representative nuclei per duct, from each of a group of 5 ducts, in two separate fields, for 10 ducts. Reproducibility of image analysis features was determined, as was the ability of features to discriminate between nuclear grades. Patient information was available about clinical factors (age and method of DCIS detection, pathologic factors (DCIS size, nuclear grade, margin size, and amount of parenchymal involvement, and 39 image features (morphology, densitometry, and texture. The prognostic effects of these factors and features on the development of invasive breast cancer were examined with Cox step-wise multivariate regression. Results Duplicate measurements were similar for 89.7% to 97.4% of assessed image features. For the pooled assessment with ~200 nuclei per patient, a discriminant function with one densitometric and two texture features was significantly (p Conclusion Image analysis provided reproducible assessments of nuclear features which quantitated differences in nuclear grading for patients. Quantitative nuclear image features indicated prognostically significant differences in DCIS, and may contribute additional information to prognostic assessments of which patients are likely to develop invasive disease.

  18. Nuclear spin optical rotation and Faraday effect in gaseous and liquid water.

    Science.gov (United States)

    Pennanen, Teemu S; Ikäläinen, Suvi; Lantto, Perttu; Vaara, Juha

    2012-05-14

    Nuclear spin optical rotation (NSOR) of linearly polarized light, due to the nuclear spins through the Faraday effect, provides a novel probe of molecular structure and could pave the way to optical detection of nuclear magnetization. We determine computationally the effects of the liquid medium on NSOR and the Verdet constant of Faraday rotation (arising from an external magnetic field) in water, using the recently developed theory applied on a first-principles molecular dynamics trajectory. The gas-to-liquid shifts of the relevant antisymmetric polarizability and, hence, NSOR magnitude are found to be -14% and -29% for (1)H and (17)O nuclei, respectively. On the other hand, medium effects both enhance the local electric field in water and, via bulk magnetization, the local magnetic field. Together these two effects partially cancel the solvation influence on the single-molecular property. We find a good agreement for the hydrogen NSOR with a recent pioneering experiment on H(2)O(l).

  19. Playing with QCD I: effective field theories

    International Nuclear Information System (INIS)

    Fraga, Eduardo S.

    2009-01-01

    The building blocks of hadrons are quarks and gluons, although color is confined into singlet states. QCD is believed to be the fundamental theory of strong interactions. Its asymptotically free nature puts the vacuum out of reach for perturbation theory. The Lagrangian of QCD and the Feynman rules associated were built by using the Gauge Principle, starting from the quark matter fields and obtaining gluons as connections. A simpler, and sometimes necessary or complementary, approach is provided by effective field theories or effective models, especially when one has to deal with the nonperturbative sector of the theory. (author)

  20. Effect of pairing on nuclear dynamics

    International Nuclear Information System (INIS)

    Scamps, Guillaume

    2014-01-01

    Pairing correlations is an essential component for the description of the atomic nuclei. The effects of pairing on static property of nuclei are now well known. In this thesis, the effect of pairing on nuclear dynamics is investigated. Theories that includes pairing are benchmarked in a model case. The TDHF+BCS theory turns out to be a good compromise between the physics taken into account and the numerical cost. This TDHF+BCS theory was retained for realistic calculations. Nevertheless, the application of pairing in the BCS approximation may induce new problems due to (1) the particle number symmetry breaking, (2) the non-conservation of the continuity equation. These difficulties are analysed in detail and solutions are proposed. In this thesis, a 3 dimensional TDHF+BCS code is developed to simulate the nuclear dynamic. Applications to giant resonances show that pairing modify only the low lying peaks. The high lying collective components are only affected by the initial conditions. An exhaustive study of the giant quadrupole resonances with the TDHF+BCS theory is performed on more than 700 spherical or deformed nuclei. Is is shown that the TDHF+BCS theory reproduces well the collective energy of the resonance. After validation on the small amplitude limit problem, the approach was applied to study nucleon transfer in heavy ion reactions. A new method to extract transfer probabilities is introduced. It is demonstrated that pairing significantly increases the two-nucleon transfer probability. (author) [fr

  1. Nuclear techniques to assess irrigation schedules for field crops. Results of a co-ordinated research programme

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-06-01

    This TECDOC summarizes the results of a Co-ordinated Research Programme on The Use of Nuclear and Related Techniques in Assessment of Irrigation Schedules of Field Crops to Increase Effective Use of Water in Irrigation Projects. The programme was carried out between 1990 and 1995 through the technical co-ordination of the Soil Fertility, Irrigation and Crop Production Section of the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture of the International Atomic Energy Agency. Fourteen Member States of the IAEA and FAO carried out a series of field experiments aimed at improving irrigation water use efficiency through a type of irrigation scheduling known as deficit irrigation. Refs, figs, tabs.

  2. Nuclear techniques to assess irrigation schedules for field crops. Results of a co-ordinated research programme

    International Nuclear Information System (INIS)

    1996-06-01

    This TECDOC summarizes the results of a Co-ordinated Research Programme on The Use of Nuclear and Related Techniques in Assessment of Irrigation Schedules of Field Crops to Increase Effective Use of Water in Irrigation Projects. The programme was carried out between 1990 and 1995 through the technical co-ordination of the Soil Fertility, Irrigation and Crop Production Section of the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture of the International Atomic Energy Agency. Fourteen Member States of the IAEA and FAO carried out a series of field experiments aimed at improving irrigation water use efficiency through a type of irrigation scheduling known as deficit irrigation. Refs, figs, tabs

  3. Magnetohydrodynamical Effects on Nuclear Deflagration Fronts in Type Ia Supernovae

    Science.gov (United States)

    Hristov, Boyan; Collins, David C.; Hoeflich, Peter; Weatherford, Charles A.; Diamond, Tiara R.

    2018-05-01

    This article presents a study of the effects of magnetic fields on non-distributed nuclear burning fronts as a possible solution to a fundamental problem for the thermonuclear explosion of a Chandrasekhar mass ({M}Ch}) white dwarf (WD), the currently favored scenario for the majority of Type Ia SNe. All existing 3D hydrodynamical simulations predict strong global mixing of the burning products due to Rayleigh–Taylor (RT) instabilities, which contradicts observations. As a first step toward studying the flame physics, we present a set of computational magnet-hydrodynamic models in rectangular flux tubes, resembling a small inner region of a WD. We consider initial magnetic fields up to {10}12 {{G}} of various orientations. We find an increasing suppression of RT instabilities starting at about {10}9 {{G}}. The front speed tends to decrease with increasing magnitude up to about {10}11 {{G}}. For even higher fields new small-scale, finger-like structures develop, which increase the burning speed by a factor of 3 to 4 above the field-free RT-dominated regime. We suggest that the new instability may provide sufficiently accelerated energy production during the distributed burning regime to go over the Chapman–Jougey limit and trigger a detonation. Finally, we discuss the possible origins of high magnetic fields during the final stage of the progenitor evolution or the explosion.

  4. Magnetic moments in present relativistic nuclear theories: a mean-field problem

    International Nuclear Information System (INIS)

    Desplanques, B.

    1986-07-01

    We show that the magnetic moments of LS closed shell nuclei plus or minus one nucleon derived from non-relativistic Hartree-Fock mean-fields are as bad as those obtained in relativistic approaches of nuclear structure. Deviations with respect to more complete results in both cases are ascribed to the mean-field approximation which neglects some degrees of freedom in the nucleus description. 18 refs

  5. Electric Field Effects in RUS Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Darling, Timothy W [Los Alamos National Laboratory; Ten Cate, James A [Los Alamos National Laboratory; Allured, Bradley [UNIV NEVADA, RENO; Carpenter, Michael A [CAMBRIDGE UNIV. UK

    2009-09-21

    Much of the power of the Resonant Ultrasound Spectroscopy (RUS) technique is the ability to make mechanical resonance measurements while the environment of the sample is changed. Temperature and magnetic field are important examples. Due to the common use of piezoelectric transducers near the sample, applied electric fields introduce complications, but many materials have technologically interesting responses to applied static and RF electric fields. Non-contact optical, buffered, or shielded transducers permit the application of charge and externally applied electric fields while making RUS measurements. For conducting samples, in vacuum, charging produces a small negative pressure in the volume of the material - a state rarely explored. At very high charges we influence the electron density near the surface so the propagation of surface waves and their resonances may give us a handle on the relationship of electron density to bond strength and elasticity. Our preliminary results indicate a charge sign dependent effect, but we are studying a number of possible other effects induced by charging. In dielectric materials, external electric fields influence the strain response, particularly in ferroelectrics. Experiments to study this connection at phase transformations are planned. The fact that many geological samples contain single crystal quartz suggests a possible use of the piezoelectric response to drive vibrations using applied RF fields. In polycrystals, averaging of strains in randomly oriented crystals implies using the 'statistical residual' strain as the drive. The ability to excite vibrations in quartzite polycrystals and arenites is explored. We present results of experimental and theoretical approaches to electric field effects using RUS methods.

  6. Preparation of substituting seaweed field mounds accompanying site preparation for No.3 plant in Ikata Nuclear Power Station

    International Nuclear Information System (INIS)

    Ishihara, Hisashi; Oshima, Teruhiko; Fujisaki, Yuichi; Saeki, Taketoshi

    1987-01-01

    Shikoku Electric Power Co., Inc. is constructing No.3 plant adjacently to No.1 and No.2 plants in operation in Ikata Nuclear Power Station. In the coastal area of Iyo-nada, many seaweed fields are distributed, which are important biologically and for fishery. In the works of site preparation for No.3 plant, a part of the site is created by reclamation of sea area, therefore the natural seaweed fields in the area disappear. From the viewpoint of various circumstances and environment preservation, it was decided to create about 60,000 m 2 of seaweed field mounds on the seabed around the site as the substitute for disappearing natural seaweed fields. The Seaweed Field Study Group composed of the men of learning and experience was organized to obtain the guidance on the possibility of creating artificial seaweed fields, the techniques for creation and the effect on environment accompanying the creation of mounds. The creation works were started in October, 1985, and are in progress smoothly utilizing effectively the stones and rocks cut in the site preparation works. The topographic and geological features, sea conditions, the present state of seaweed fields, the experiment on creating artificial seaweed fields, the design and construction of mounds and others are reported. (Kako, I.)

  7. Feasibility of liquid membrane extraction in nuclear field. Vol. 1

    Energy Technology Data Exchange (ETDEWEB)

    Macasek, F [Department of Nuclear Chemistry, Comenius University SK-84215 Bratislava, (Slovakia)

    1996-03-01

    Membrane separation processes are widely used in separation science mainly in food and water processing. It is discussed, how far the liquid membranes, both supported and emulsion ones are suitable for trace metals, and radionuclides recovery from aqueous solutions and wastes. The advantage of liquid membranes processes are in high preconcentration capability, also emulsion membranes provides possibility to use kinetic effects for specific separation. Radiation sensitivity of the systems is considered as well as the main disadvantage because of surface active products accumulation in such systems. 3 figs.

  8. Effects of magnetic fields on main sequence stars

    International Nuclear Information System (INIS)

    Hubbard, E.N.

    1981-01-01

    A number of effects of low to medium strength ( 2 /8π) magnetic field pressure term so that the only effect of such a field may come from its inhibiting convection in the core. Isochrones of both convective and radiative core models of 2-5 M are presented. In the deep envelope, mixing of partially nuclear processed material driven by rising and falling magnetic flux tubes may be seen. The effects of this mixing will be brought to the surface during the deep convection phase of the star's tenure as a red giant. This model is used to predict a signature for magnetic mixing based on the CNO isotope and abundance ratios. In the outer envelope the gas pressure is low enough that one might expect to see a perturbation of the stellar structure due to the magnetic field pressure itself. This perturbation is calculated under several physical models for intermediate and high mass stars and it is determined that sufficient magnetic field energy may be available in the outer envelope to expand a star by about 20% over its unperturbed radius. Finally the evidence for the existence of non-magnetic neutron stars is considered, concluding that while no non-magnetic neutron stars have ever been positively identified, there is no evidence that prevents the existence of at least as many non-magnetic as magnetic neutron stars

  9. Effective field theory for magnetic compactifications

    Energy Technology Data Exchange (ETDEWEB)

    Buchmuller, Wilfried; Dierigl, Markus [Deutsches Elektronen-Synchrotron DESY,22607 Hamburg (Germany); Dudas, Emilian [Centre de Physique Théorique, École Polytechnique, CNRS, Université Paris-Saclay,F-91128 Palaiseau (France); Schweizer, Julian [Deutsches Elektronen-Synchrotron DESY,22607 Hamburg (Germany)

    2017-04-10

    Magnetic flux plays an important role in compactifications of field and string theories in two ways, it generates a multiplicity of chiral fermion zero modes and it can break supersymmetry. We derive the complete four-dimensional effective action for N=1 supersymmetric Abelian and non-Abelian gauge theories in six dimensions compactified on a torus with flux. The effective action contains the tower of charged states and it accounts for the mass spectrum of bosonic and fermionic fields as well as their level-dependent interactions. This allows us to compute quantum corrections to the mass and couplings of Wilson lines. We find that the one-loop corrections vanish, contrary to the case without flux. This can be traced back to the spontaneous breaking of symmetries of the six-dimensional theory by the background gauge field, with the Wilson lines as Goldstone bosons.

  10. Gravitational effects in field gravitation theory

    International Nuclear Information System (INIS)

    Denisov, V.I.; Logunov, A.A.; Mestvirishvili, M.A.; Vlasov, A.A.

    1979-01-01

    The possibilities to describe various gravitation effects of field gravitation theory (FGT) are considered. Past-Newtonian approximation of the FGT has been constructed and on the basis of this approximation it has been shown that the field theory allows one to describe the whole set of experimental facts. The comparison of post-Newtonian parameters in FGT with those in the Einstein's theory makes it clear that these two; theories are undistinguishable from the viewpoint of any experiments, realized with post-Newtonian accuracy. Gravitational field of an island type source with spherically symmetrical distribution of matter and unstationary homogeneous model of Universe, which allows to describe the effect of cosmological red shift, are considered

  11. On the derivation of effective field theories

    International Nuclear Information System (INIS)

    Uzunov, Dimo I.

    2004-12-01

    A general self-consistency approach allows a thorough treatment of the corrections to the standard mean-field approximation (MFA). The natural extension of standard MFA with the help of cumulant expansion leads to a new point of view on the effective field theories. The proposed approach can be used for a systematic treatment of fluctuation effects of various length scales and, perhaps, for the development of a new coarse graining procedure. We outline and justify our method by some preliminary calculations. Concrete results are given for the critical temperature and the Landau parameters of the φ 4 -theory - the field counterpart of the Ising model. An important unresolved problem of the modern theory of phase transitions - the problem for the calculation of the true critical temperature, is considered within the framework of the present approach. A comprehensive description of the ground state properties of many-body systems is also demonstrated. (author)

  12. PROBABILISTIC APPROACH OF STABILIZED ELECTROMAGNETIC FIELD EFFECTS

    Directory of Open Access Journals (Sweden)

    FELEA. I.

    2017-09-01

    Full Text Available The effects of the omnipresence of the electromagnetic field are certain and recognized. Assessing as accurately as possible these effects, which characterize random phenomena require the use of statistical-probabilistic calculation. This paper aims at assessing the probability of exceeding the admissible values of the characteristic sizes of the electromagnetic field - magnetic induction and electric field strength. The first part justifies the need for concern and specifies how to approach it. The mathematical model of approach and treatment is presented in the second part of the paper and the results obtained with reference to 14 power stations are synthesized in the third part. In the last part, are formulated the conclusions of the evaluations.

  13. Research Programs in the Field of Nuclear Power Engineering and Technologies in the Republic of Kazakhstan

    International Nuclear Information System (INIS)

    Cherepnin, Yu. S.; Takibaev, Zh. S.

    2000-01-01

    In 1991 the Semipalatinsk Test Site (STS) was closed under the decree of President of the Republic of Kazakhstan, N.A. Nazarbayev. Later, the National Nuclear Center of the Republic of Kazakhstan (NNC RK) was established under President's decree 779 dated May 15 1992. A range of NNC RK activity was specified in the decree: ' To create National Nuclear Center of the Republic of Kazakhstan on the basis of the former Semipalatinsk Test Site and appropriate scientific organizations and facilities situated in the Republic of Kazakhstan with a view to conduct work on radiation safety and ecology, investigation of problems related to utilization and radioactive waste disposal, development work in the field of nuclear technology and nuclear power engineering'. Tasks outlined in this decree, later on, became the work program of NNC RK

  14. Safety targets and public risk perceptions in the nuclear field - technical treadmill or institutional responses?

    International Nuclear Information System (INIS)

    Wynne, B.

    1989-01-01

    The context of our treatment of risk perceptions and safety targets is the apparently wide gap between expert judgements of 'objective risks' and public perceptions of those risks. In the nuclear field the latter appear to so multiply the objective risks as seen by the experts, as to make safety targets vastly too strict (whether for routine discharges or for large accidents), thus design extravagantly expensive on any 'rational' criteria. In recent years the nuclear industry has come to terms more with the public perceptions problem, and has accepted that it is legitimate to exercise different, more severe and costly safety standards in the nuclear field if that is what society wants, as it appears to do. Whilst retaining the conviction that this is scientifically unwarranted, the industry has therefore reconciled itself somewhat to more stringent technical safety targets. (author)

  15. On some nonlinear effects in ultrasonic fields

    Science.gov (United States)

    Tjotta

    2000-03-01

    Nonlinear effects associated with intense sound fields in fluids are considered theoretically. Special attention is directed to the study of higher effects that cannot be described within the standard propagation models of nonlinear acoustics (the KZK and Burgers equations). The analysis is based on the fundamental equations of motion for a thermoviscous fluid, for which thermal equations of state exist. Model equations are derived and used to analyze nonlinear sources for generation of flow and heat, and other changes in the ambient state of the fluid. Fluctuations in the coefficients of viscosity and thermal conductivity caused by the sound field, are accounted for. Also considered are nonlinear effects induced in the fluid by flexural vibrations. The intensity and absorption of finite amplitude sound waves are calculated, and related to the sources for generation of higher order effects.

  16. EDF, a utility and its own needs in the field of transport of nuclear materials

    International Nuclear Information System (INIS)

    Gouin, P.; Mignot, E.; Hoang, L.P.

    1989-01-01

    As one of the most important producers of nuclear electricity in the world, EDF is concerned by all the aspects of the transport of nuclear materials and more particularly by those related to the nuclear fuel cycle. EDF is not itself a specialist in this field and most of the transports along the nuclear fuel cycle is done for their own account by their usual partners such as COGEMA or TRANSNUCLEAIRE. Since the beginning of the French nuclear program, they have generally used for these transports casks that already exist on the market and which were well suited to their needs. Nevertheless, new and specific needs appeared during the progress of their nuclear program and have lead them to: study and build new casks or packages, use existing casks for new purposes, develop a device for the measurement of fuel assemblies burn up, develop a software to optimize the evacuation of irradiated fuel for reprocessing. The purpose of this paper is to describe these realization but as a preliminary, they will present briefly the importance of the transport of nuclear materials for EDF

  17. Country report present status and need of human resource development in nuclear field in Vietnam

    International Nuclear Information System (INIS)

    Ngo Qui Viet; Vu Dang Ninh

    2000-01-01

    Vietnam Atomic Energy Commission (VAEC) was officially established in 1976, and is a national research and development organization in the field of nuclear science and technology for peaceful purposes in Vietnam. Under the VAEC, there are three institutes and one center. Status of main facilities, such as TRIGA MARK II, neutron generator, electron accelerator MT-17, and irradiation facilities are outlined in the paper. At present, the VAEC has a total staff of about 540 persons. The number of staff appears adequate to fulfill the present task on application of isotopes and nuclear techniques. When Vietnam decides to develop nuclear power program, the demand for human resources will be significantly high. During the last five years, Vietnam has been developing and implementing a national regulatory program on Radiation Protection and Nuclear Safety. The Ministry of Science, Technology and Environment (MOSTE) have established independent Vietnam Radiation Protection and Nuclear Safety Authority (VRPA) in 1994. If the Vietnamese Government approves the proposed nuclear power program, human resources training should be a key point for all research and development directions at all revel of personnel. When looking back in the history of formation and development of nuclear science and technology in Vietnam, the international cooperation has played an extremely important role in promoting the program. The exchange of information and direct participation in concrete cooperation activities under the framework of the Forum are expected. (Tanaka, Y.)

  18. Country report present status and need of human resource development in nuclear field in Vietnam

    Energy Technology Data Exchange (ETDEWEB)

    Ngo Qui Viet [Department of Organization and Scientific Human Resource Development, The Ministry of Science, Technology and Environment, Hanoi (Viet Nam); Vu Dang Ninh [Department of Administration and Personnel, The Vietnam Atomic Energy Commission, Hanoi (Viet Nam)

    2000-12-01

    Vietnam Atomic Energy Commission (VAEC) was officially established in 1976, and is a national research and development organization in the field of nuclear science and technology for peaceful purposes in Vietnam. Under the VAEC, there are three institutes and one center. Status of main facilities, such as TRIGA MARK II, neutron generator, electron accelerator MT-17, and irradiation facilities are outlined in the paper. At present, the VAEC has a total staff of about 540 persons. The number of staff appears adequate to fulfill the present task on application of isotopes and nuclear techniques. When Vietnam decides to develop nuclear power program, the demand for human resources will be significantly high. During the last five years, Vietnam has been developing and implementing a national regulatory program on Radiation Protection and Nuclear Safety. The Ministry of Science, Technology and Environment (MOSTE) have established independent Vietnam Radiation Protection and Nuclear Safety Authority (VRPA) in 1994. If the Vietnamese Government approves the proposed nuclear power program, human resources training should be a key point for all research and development directions at all revel of personnel. When looking back in the history of formation and development of nuclear science and technology in Vietnam, the international cooperation has played an extremely important role in promoting the program. The exchange of information and direct participation in concrete cooperation activities under the framework of the Forum are expected. (Tanaka, Y.)

  19. Strategy of the Romanian Public Information Policy in the Nuclear Field

    International Nuclear Information System (INIS)

    Stiopol, Mihaela; Manole, Felicia; Paunescu, Aurelia; Petran, Catalina; Chiper, Livia

    1998-01-01

    In the framework the Romania's nuclear power program the first Romanian NPP has been built at Cernavoda and the Unit 1, based on a CANDU type reactor, was commissioned on December 2, 1996. The start of the entire nuclear program in Romania, some 20 years ago, was a high level government decision with no public hearing or acceptance, either, but obviously based on economic and political considerations. After 1990 favorable and unfavorable articles in the mass media, most of them lacking of technical background, had led to distorted and false perception of information. The strategy of public information policy in the nuclear field should be guided by the following facts: a) the public perception of the nuclear energy problems in general, and of nuclear power, in particular, is deeply deformed by the ignorance in the domain; b) first of all the public fears for its health menaced by radiation and radioactive wastes; c) the public due not know the actual dimension and potential of the Romanian industry in this field, the qualitative progress brought about by the implementation of the nuclear program in the Romania's economy; d) the public vulnerability when exposed to the mass media which, owing to its rush towards sensational or due to the lack of knowledge in the field, rather often have launched simple, unfounded speculations. The paper presents the basic principles which are underlying the public information program and lists suggestions for the future activity concerning: A - the educational programs addressed to young people; B - development of computer-assisted educational programs; C - the relationship with mass media; D - accomplishing an adequate information through publications; E - organizing and/or participating in exhibitions displaying nuclear power development; F - advertising actions related to promotion of Unit 2 - 5 project at Cernavoda NPP

  20. An overview of digital image processing in the field of nuclear medicine

    International Nuclear Information System (INIS)

    Okuyama, Yasuo

    1992-01-01

    The current status and remaining problems of digital image processing in nuclear medicine were discussed. Digitalization of nuclear medicine images has made it possible, in conjunction with computers, to obtain new information (Fourier analysis, Factor analysis, etc.) with added value from images, in place of the fixed concepts that had formerly been drawn only from images. However, the basis of this technology is the special QC and QA of nuclear medicine examinations, and those techniques have not yet been adequately established. The advantage of digitalization is the flexibility that comes from the programs, but the element of the subjectivity of each individual plays a large role, and it can be said that there is also the risk that the logic of image diagnosis established to date will be destroyed. Accordingly, the creation of digital image processing technique with specifications will give birth to standardized digital nuclear medicine images, and these development will certainly lead to progress in nuclear medicine diagnosis. In addition, in comparison with other modalities, the field of nuclear medicine involves a lesser amount of information, and this simplifiers the digitalization of images. At present, equipment is being designed and developed with incorporation of the concept of a work station. A serious problem that remains in this field is the standardization of image transmission. In summary, the main problem that must be solved in the field of nuclear medicine examinations is the establishment of QC and QA methods and practical algorithms for the software. It is hoped that there will be open access to information, etc., related to the software. (author)

  1. Ferromagnetic hysteresis and the effective field

    NARCIS (Netherlands)

    Naus, H.W.L.

    2002-01-01

    The Jiles-Atherton model of the behavior of ferromagnetic materials determines the irreversible magnetization from the effective field by using a differential equation. This paper presents an exact, analytical solution to the equation, one displaying hysteresis. The inclusion of magnetomechanical

  2. Recent status of development and practical application of risk analysis in the nuclear field

    International Nuclear Information System (INIS)

    Birkhofer, A.

    1980-01-01

    The present status of reliability as well as of risk analysis in the field of nuclear safety in the Federal Republic of Germany, is described. An attempt is made to select typical examples rather than to give a complete survey. (E.G.) [pt

  3. Computer-based measurement and automatizatio aplication research in nuclear technology fields

    International Nuclear Information System (INIS)

    Jiang Hongfei; Zhang Xiangyang

    2003-01-01

    This paper introduces computer-based measurement and automatization application research in nuclear technology fields. The emphasis of narration are the role of software in the development of system, and the network measurement and control software model which has optimistic application foreground. And presents the application examples of research and development. (authors)

  4. 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

  5. The separation of heavy ion tracks in nuclear emulsions by means of the pulsed electric field

    International Nuclear Information System (INIS)

    Akopova, A.B.; Magradze, N.V.; Melkumyan, L.V.; Prokhorenko, Y.P.

    1976-01-01

    The pulsed electric field (PEF) technique is developed for the separation of heavy ion tracks from the intense background caused by high energy electrons, protons and γ-radiation. The tracks of Ne, Cr, Ar-ions accelerated at the Dubna Nuclear Reactions Laboratory have been separated from the background, the voltage of the applied PEF being 10 5 V/cm. (orig.) [de

  6. Summary of OECD survey of education in the nuclear energy field in Finland

    International Nuclear Information System (INIS)

    Kalli, H.

    1999-01-01

    This summary is a part of the work in the OECD/NEA/NDC expert group on the survey and analysis of education in the nuclear field. The text will later be published as a country report in the final report by expert group. (author)

  7. Effect of pairing in nuclear level density at low temperatures

    International Nuclear Information System (INIS)

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

    2013-01-01

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

  8. ALPs effective field theory and collider signatures

    DEFF Research Database (Denmark)

    Brivio, I.; Gavela, M. B.; Merlo, L.

    2017-01-01

    We study the leading effective interactions between the Standard Model fields and a generic singlet CP-odd (pseudo-) Goldstone boson. Two possible frameworks for electroweak symmetry breaking are considered: linear and non-linear. For the latter case, the basis of leading effective operators is d...... final states are most promising signals expected in both frameworks. In addition, non-standard Higgs decays and mono-Higgs signatures are especially prominent and expected to be dominant in non-linear realisations....

  9. Predictive power of theoretical modelling of the nuclear mean field: examples of improving predictive capacities

    Science.gov (United States)

    Dedes, I.; Dudek, J.

    2018-03-01

    We examine the effects of the parametric correlations on the predictive capacities of the theoretical modelling keeping in mind the nuclear structure applications. The main purpose of this work is to illustrate the method of establishing the presence and determining the form of parametric correlations within a model as well as an algorithm of elimination by substitution (see text) of parametric correlations. We examine the effects of the elimination of the parametric correlations on the stabilisation of the model predictions further and further away from the fitting zone. It follows that the choice of the physics case and the selection of the associated model are of secondary importance in this case. Under these circumstances we give priority to the relative simplicity of the underlying mathematical algorithm, provided the model is realistic. Following such criteria, we focus specifically on an important but relatively simple case of doubly magic spherical nuclei. To profit from the algorithmic simplicity we chose working with the phenomenological spherically symmetric Woods–Saxon mean-field. We employ two variants of the underlying Hamiltonian, the traditional one involving both the central and the spin orbit potential in the Woods–Saxon form and the more advanced version with the self-consistent density-dependent spin–orbit interaction. We compare the effects of eliminating of various types of correlations and discuss the improvement of the quality of predictions (‘predictive power’) under realistic parameter adjustment conditions.

  10. Relativistic and Nuclear Medium Effects on the Coulomb Sum Rule.

    Science.gov (United States)

    Cloët, Ian C; Bentz, Wolfgang; Thomas, Anthony W

    2016-01-22

    In light of the forthcoming high precision quasielastic electron scattering data from Jefferson Lab, it is timely for the various approaches to nuclear structure to make robust predictions for the associated response functions. With this in mind, we focus here on the longitudinal response function and the corresponding Coulomb sum rule for isospin-symmetric nuclear matter at various baryon densities. Using a quantum field-theoretic quark-level approach which preserves the symmetries of quantum chromodynamics, as well as exhibiting dynamical chiral symmetry breaking and quark confinement, we find a dramatic quenching of the Coulomb sum rule for momentum transfers |q|≳0.5  GeV. The main driver of this effect lies in changes to the proton Dirac form factor induced by the nuclear medium. Such a dramatic quenching of the Coulomb sum rule was not seen in a recent quantum Monte Carlo calculation for carbon, suggesting that the Jefferson Lab data may well shed new light on the explicit role of QCD in nuclei.

  11. Effects of the Fukushima Daiichi nuclear accident on goshawk reproduction

    Science.gov (United States)

    Murase, Kaori; Murase, Joe; Horie, Reiko; Endo, Koichi

    2015-01-01

    Although the influence of nuclear accidents on the reproduction of top predators has not been investigated, it is important that we identify the effects of such accidents because humans are also top predators. We conducted field observation for 22 years and analysed the reproductive performance of the goshawk (Accipiter gentilis fujiyamae), a top avian predator in the North Kanto area of Japan, before and after the accidents at the Fukushima Daiichi nuclear power plant that occurred in 2011. The reproductive performance declined markedly compared with the pre-accident years and progressively decreased for the three post-accident study years. Moreover, it was suggested that these declines were primarily caused by an increase in the air dose rate of radio-active contaminants measured under the nests caused by the nuclear accidents, rather than by other factors. We consider the trends in the changes of the reproductive success rates and suggest that internal exposure may play an important role in the reproductive performance of the goshawk, as well as external exposure. PMID:25802117

  12. Kyoto: nuclear power against greenhouse effect

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    Among the different possibilities to slow down the increase of greenhouse gas emissions, several participants of the Kyoto conference (December 11, 1997) held the nuclear power resort in a good position. This short paper reports on some extracts of talks given during the conference by participants who take a definite position in favour of the development of nuclear power: FORATOM (European Atomic Forum), Nuclear Energy Institute (US), Japan Atomic Industrial Forum, the Uranium Institute, WONUC (World Council of Nuclear Workers) and SFEN (French Society of Nuclear Energy). (J.S.)

  13. Skyrme's interaction beyond the mean-field. The DGCM+GOA Hamiltonian of nuclear quadrupole motion

    International Nuclear Information System (INIS)

    Kluepfel, Peter

    2008-01-01

    This work focuses on the microscopic description of nuclear collective quadrupole motion within the framework of the dynamic Generator-Coordinate-Method(DGCM)+Gaussian-Overlap-Approximation(GOA). Skyrme-type effective interactions are used as the fundamental many-particle interaction. Starting from a rotational invariant, polynomial and topologic consistent formulation of the GCM+GOA Hamiltonian an interpolation scheme for the collective masses and potential is developed. It allows to define the collective Hamiltonian of fully triaxial collective quadrupole dynamics from a purely axial symmetric configuration space. The substantial gain in performance allows the self-consistent evaluation of the dynamic quadrupole mass within the ATDHF-cranking model. This work presents the first large-scale analysis of quadrupole correlation energies and lowlying collective states within the DGCM+GOA model. Different Skyrme- and pairing interactions are compared from old standards up to more recent parameterizations. After checking the validity of several approximations to the DGCM+GOA model - both on the mean-field and the collective level - we proceed with a detailed investigation of correlation effects along the chains of semi-magic isotopes and isotones. This finally allows to define a set of observables which are hardly affected by collective correlations. Those observables were used for a refit of a Skyrme-type effective interaction which is expected to cure most of the problems of the recent parameterizations. Preparing further work, estimates for the correlated ground state energy are proposed which can be evaluated directly from the mean-field model. (orig.)

  14. Skyrme's interaction beyond the mean-field. The DGCM+GOA Hamiltonian of nuclear quadrupole motion

    Energy Technology Data Exchange (ETDEWEB)

    Kluepfel, Peter

    2008-07-29

    This work focuses on the microscopic description of nuclear collective quadrupole motion within the framework of the dynamic Generator-Coordinate-Method(DGCM)+Gaussian-Overlap-Approximation(GOA). Skyrme-type effective interactions are used as the fundamental many-particle interaction. Starting from a rotational invariant, polynomial and topologic consistent formulation of the GCM+GOA Hamiltonian an interpolation scheme for the collective masses and potential is developed. It allows to define the collective Hamiltonian of fully triaxial collective quadrupole dynamics from a purely axial symmetric configuration space. The substantial gain in performance allows the self-consistent evaluation of the dynamic quadrupole mass within the ATDHF-cranking model. This work presents the first large-scale analysis of quadrupole correlation energies and lowlying collective states within the DGCM+GOA model. Different Skyrme- and pairing interactions are compared from old standards up to more recent parameterizations. After checking the validity of several approximations to the DGCM+GOA model - both on the mean-field and the collective level - we proceed with a detailed investigation of correlation effects along the chains of semi-magic isotopes and isotones. This finally allows to define a set of observables which are hardly affected by collective correlations. Those observables were used for a refit of a Skyrme-type effective interaction which is expected to cure most of the problems of the recent parameterizations. Preparing further work, estimates for the correlated ground state energy are proposed which can be evaluated directly from the mean-field model. (orig.)

  15. Toroidal field ripple effects in large tokamaks

    International Nuclear Information System (INIS)

    Uckan, N.A.; Tsang, K.T.; Callen, J.D.

    1975-01-01

    In an experimental power reactor, the ripple produced by the finite number of toroidal field coils destroys the ideal axisymmetry of the configuration and is responsible for additional particle trapping, loss regions and plasma transport. The effects of toroidal field ripple on the plasma transport coefficient, the loss of alpha particles and energetic injection ions, and the relaxation of toroidal flows are investigated in a new and systematic way. The relevant results are applied to the ORNL-EPR reference design; the maximum ripple there of about 2.2 percent at the outer edge of the plasma column is found to be tolerable from plasma physics considerations

  16. Adolescents' knowledge of nuclear issues and the effects of nuclear war

    International Nuclear Information System (INIS)

    Roscoe, B.; Goodwin, M.P.

    1987-01-01

    Three hundred fifty-seven college students were surveyed to assess later adolescents' awareness of the status of nuclear arms development and possible effects of a nuclear war on people and the environment. Chi-square analyses were performed to determine whether the frequency of correct responses differed with regard to participants' sex, political orientation, and position toward the United States' possession of nuclear weapons. Results suggest that later adolescents are extremely uninformed regarding the current status of nuclear issues and the consequences of a nuclear war. These data, coupled with findings from previous studies reporting children's and adolescents' concerns and fears about nuclear war, indicate that there is a strong need to educate young people concerning nuclear issues

  17. Nuclear spectroscopy with density dependent effective interactions

    International Nuclear Information System (INIS)

    Krewald, S.

    1976-07-01

    The paper investigates excited nuclear states with density-dependent effective interactions. In the first part of the paper, the structure and the width of the multipole giant resonances discovered in 1972 are derived microscopically. Because of their high excitation energy, these giant resonances are unstable to particle emission and thus often have a considerable decay width. Due to their collective structure, the giant resonances can be described by RPA in good approximation. In this paper, the continuum RPA is applied to the spherical nuclei 16 O, 40 Ca, 90 Zr and 208 Pb. The experimental centroid energy are in very good agreement with the calculations performed in the paper. (orig./WL) [de

  18. Nuclear power and the greenhouse effect

    International Nuclear Information System (INIS)

    Donaldson, D; Tolland, H.; Grimston, M.

    1990-01-01

    The greenhouse effect is first explained. The evidence is shown in global warming and changing weather patterns which are generally believed to be due to the emission of greenhouse gases, including carbon dioxide. Serious consequences are predicted if emission of the greenhouse gases is not reduced. Sources of these gases are identified - agriculture, carbon fluorocarbons, coal-fired power stations, vehicle exhausts. The need is to use energy more efficiently but such measures as combined heat and power stations, more fuel efficient cars and better thermal insulation in homes is advocated. The expansion of renewable energy sources such as wind and water power is also suggested. Nuclear power is promoted as it reduces the carbon dioxide emissions and in both the short and long-term will reduce the emission of greenhouse gases. (author)

  19. Numerical forecast test on local wind fields at Qinshan Nuclear Power Plant

    International Nuclear Information System (INIS)

    Chen Xiaoqiu

    2005-01-01

    Non-hydrostatic, full compressible atmospheric dynamics model is applied to perform numerical forecast test on local wind fields at Qinshan nuclear power plant, and prognostic data are compared with observed data for wind fields. The results show that the prognostic of wind speeds is better than that of wind directions as compared with observed results. As the whole, the results of prognostic wind field are consistent with meteorological observation data, 54% of wind speeds are within a factor of 1.5, about 61% of the deviation of wind direction within the 1.5 azimuth (≤33.75 degrees) in the first six hours. (authors)

  20. Electrical Initialization of Electron and Nuclear Spins in a Single Quantum Dot at Zero Magnetic Field.

    Science.gov (United States)

    Cadiz, Fabian; Djeffal, Abdelhak; Lagarde, Delphine; Balocchi, Andrea; Tao, Bingshan; Xu, Bo; Liang, Shiheng; Stoffel, Mathieu; Devaux, Xavier; Jaffres, Henri; George, Jean-Marie; Hehn, Michel; Mangin, Stephane; Carrere, Helene; Marie, Xavier; Amand, Thierry; Han, Xiufeng; Wang, Zhanguo; Urbaszek, Bernhard; Lu, Yuan; Renucci, Pierre

    2018-04-11

    The emission of circularly polarized light from a single quantum dot relies on the injection of carriers with well-defined spin polarization. Here we demonstrate single dot electroluminescence (EL) with a circular polarization degree up to 35% at zero applied magnetic field. The injection of spin-polarized electrons is achieved by combining ultrathin CoFeB electrodes on top of a spin-LED device with p-type InGaAs quantum dots in the active region. We measure an Overhauser shift of several microelectronvolts at zero magnetic field for the positively charged exciton (trion X + ) EL emission, which changes sign as we reverse the injected electron spin orientation. This is a signature of dynamic polarization of the nuclear spins in the quantum dot induced by the hyperfine interaction with the electrically injected electron spin. This study paves the way for electrical control of nuclear spin polarization in a single quantum dot without any external magnetic field.

  1. Thermo field dynamics in the treatment of the nuclear pairing problem at finite temperature

    International Nuclear Information System (INIS)

    Civitarese, O.; DePaoli, A.L.

    1993-01-01

    The use of the thermo field dynamics, in dealing with the study of nuclear properties at finite temperature, is discussed for the case of a nuclear Hamiltonian which includes a single-particle term and a monopole pairing residual two-body interaction. The rules of the thermo fields dynamics are applied to double the Hilbert space, thus accounting for the thermal occupation of single-particle states, and to construct dual spaces, both for single-particle (BCS) and collective (RPA) degrees of freedom. It is shown that the rules of the thermo field dynamics yield to a temperature dependence of the equations describing quasiparticle and phonon excitations which is similar to the one found in the more conventional finite temperature Wick's theorem approach, namely: By dealing with thermal averages. (orig.)

  2. Band mixing effects in mean field theories

    International Nuclear Information System (INIS)

    Kuyucak, S.; Morrison, I.

    1989-01-01

    The 1/N expansion method, which is an angular momentum projected mean field theory, is used to investigate the nature of electromagnetic transitions in the interacting boson model (IBM). Conversely, comparison with the exact IBM results sheds light on the range of validity of the mean field theory. It is shown that the projected mean field results for the E2 transitions among the ground, β and γ bands are incomplete for the spin dependent terms and it is essential to include band mixing effect for a correct (Mikhailov) analysis of E2 data. The algebraic expressions derived are general and will be useful in the analysis of experimental data in terms of both the sd and sdg boson models. 17 refs., 7 figs., 8 tabs

  3. Field Effect Microparticle Generation for Cell Microencapsulation.

    Science.gov (United States)

    Hsu, Brend Ray-Sea; Fu, Shin-Huei

    2017-01-01

    The diameter and sphericity of alginate-poly-L-lysine-alginate microcapsules, determined by the size and the shape of calcium alginate microspheres, affect their in vivo durability and biocompatibility and the results of transplantation. The commonly used air-jet spray method generates microspheres with a wider variation in diameter, larger sphere morphology, and evenly distributed encapsulated cells. In order to overcome these drawbacks, we designed a field effect microparticle generator to create a stable electric field to prepare microparticles with a smaller diameter and more uniform morphology. Using this electric field microparticle generator the encapsulated cells will be located at the periphery of the microspheres, and thus the supply of oxygen and nutrients for the encapsulated cells will be improved compared with the centrally located encapsulated cells in the air-jet spray method.

  4. Nuclear elastic scattering effects on fusion product transport in the FRM

    International Nuclear Information System (INIS)

    DeVeaux, J.C.; Greenspan, E.; Miley, G.H.

    1981-01-01

    Large energy transfer (LET) events such as nuclear elastic scatterng (NES) are shown to have significant effects on fusion product transport in the field-reversed mirror. The method used and preliminary results obtained from the study on NES effects on f/sub p/ orbits are described

  5. Psychotherapist countertransference in the nuclear age: Effects on therapeutic interventions

    International Nuclear Information System (INIS)

    Oderberg, N.A.

    1991-01-01

    Since the early 1980s, there has been considerable attention in the psychology literature to mental health problems related to living in a world threatened by nuclear destruction. Questionnaires were mailed to 630 psychotherapists from the Colorado Psychological Association, California Psychotherapists for Social Responsibility, California Psychologists for Social Responsibility, the US Army, and the APA Division of Military Psychology; 174 questionnaires were returned. It was hypothesized that liberalism, nuclear weapons opposition, nuclear concern, nuclear awareness, and anti-nuclear activism in psychotherapists would facilitate perception of, and openness to working with, a client's nuclear concerns and thus, would be positively correlated with intentions to discuss nuclear issues with clients in three different clinical vignettes. Results indicated that when controlling for subject group, psychotherapy orientation, age, sex, and income, all five independent variables were positively correlated with responses to all three clinical vignettes, with nuclear concern having the strongest unique effect in accounting for variance in responses to the vignettes

  6. Ductal carcinoma in situ of the breast (DCIS) with heterogeneity of nuclear grade: prognostic effects of quantitative nuclear assessment

    International Nuclear Information System (INIS)

    Chapman, Judith-Anne W; Miller, Naomi A; Lickley, H Lavina A; Qian, Jin; Christens-Barry, William A; Fu, Yuejiao; Yuan, Yan; Axelrod, David E

    2007-01-01

    Previously, 50% of patients with breast ductal carcinoma in situ (DCIS) had more than one nuclear grade, and neither worst nor predominant nuclear grade was significantly associated with development of invasive carcinoma. Here, we used image analysis in addition to histologic evaluation to determine if quantification of nuclear features could provide additional prognostic information and hence impact prognostic assessments. Nuclear image features were extracted from about 200 nuclei of each of 80 patients with DCIS who underwent lumpectomy alone, and received no adjuvant systemic therapy. Nuclear images were obtained from 20 representative nuclei per duct, from each of a group of 5 ducts, in two separate fields, for 10 ducts. Reproducibility of image analysis features was determined, as was the ability of features to discriminate between nuclear grades. Patient information was available about clinical factors (age and method of DCIS detection), pathologic factors (DCIS size, nuclear grade, margin size, and amount of parenchymal involvement), and 39 image features (morphology, densitometry, and texture). The prognostic effects of these factors and features on the development of invasive breast cancer were examined with Cox step-wise multivariate regression. Duplicate measurements were similar for 89.7% to 97.4% of assessed image features. For the pooled assessment with ~200 nuclei per patient, a discriminant function with one densitometric and two texture features was significantly (p < 0.001) associated with nuclear grading, and provided 78.8% correct jackknifed classification of a patient's nuclear grade. In multivariate assessments, image analysis nuclear features had significant prognostic associations (p ≤ 0.05) with the development of invasive breast cancer. Texture (difference entropy, p < 0.001; contrast, p < 0.001; peak transition probability, p = 0.01), densitometry (range density, p = 0.004), and measured margin (p = 0.05) were associated with

  7. Effectiveness of the Convention on Nuclear Safety

    International Nuclear Information System (INIS)

    Schwarz, G.

    2016-01-01

    The Convention on Nuclear Safety (CNS) has been established after the Chernobyl accident with the primary objective of achieving and maintaining a high level of nuclear safety worldwide, through the enhancement of national measures and international cooperation. The CNS is an incentive convention. It defines the basic safety standard which shall be met by the Contracting Parties. The verification of compliance is based on a self-assessment by the Countries and a Peer Review by the other Contracting Parties. As of July 2015, there are 78 Contracting Parties. Among the Contracting Parties of the Convention are all countries operating nuclear power plants except the Islamic Republic of Iran and Taiwan, all countries constructing nuclear power plants, all countries having nuclear power plants in long term shutdown and all countries having signed contracts for the construction of nuclear power plants. The National Reports under the CNS therefore cover almost all nuclear power plants of the world. The peer review of reports, questions and answers that are exchanged in connection with the Review Meetings provided a unique overview of nuclear safety provisions and issues in countries planning or operating nuclear power plants. This is especially important for neighbouring countries to those operating nuclear power plants.

  8. Field theory approach to quantum hall effect

    International Nuclear Information System (INIS)

    Cabo, A.; Chaichian, M.

    1990-07-01

    The Fradkin's formulation of statistical field theory is applied to the Coulomb interacting electron gas in a magnetic field. The electrons are confined to a plane in normal 3D-space and also interact with the physical 3D-electromagnetic field. The magnetic translation group (MTG) Ward identities are derived. Using them it is shown that the exact electron propagator is diagonalized in the basis of the wave functions of the free electron in a magnetic field whenever the MTG is unbroken. The general tensor structure of the polarization operator is obtained and used to show that the Chern-Simons action always describes the Hall effect properties of the system. A general proof of the Streda formula for the Hall conductivity is presented. It follows that the coefficient of the Chern-Simons terms in the long-wavelength approximation is exactly given by this relation. Such a formula, expressing the Hall conductivity as a simple derivative, in combination with diagonal form of the full propagator allows to obtain a simple expressions for the filling factor and the Hall conductivity. Indeed, these results, after assuming that the chemical potential lies in a gap of the density of states, lead to the conclusion that the Hall conductivity is given without corrections by σ xy = νe 2 /h where ν is the filling factor. In addition it follows that the filling factor is independent of the magnetic field if the chemical potential remains in the gap. (author). 21 ref, 1 fig

  9. Dual Liability for Nuclear Damage in Conventions and Finnish Legislation in the Field of Transport

    International Nuclear Information System (INIS)

    Manninen, J.

    1986-01-01

    The exception made in the 1960 Paris Convention on Third Party Liability in the Field of Nuclear Energy to the otherwise absolute channelling of liability in order to avoid conflicts with the then existing international agreements in the field of transport is briefly described. The dual liability created by this provision is studied, as well as the question whether and when the victim might prefer to base his claim on a transport agreement instead of the Paris Convention. The so-called nuclear clauses in the new agreements in the transport field are analysed. The problems caused by the absence of a nuclear clause in the Guatemala City and Montreal Protocols, amending the Warsaw Convention relating to international air carriage are noted. Finally the relationship between nuclear liability legislation and transport legislation in Finland, as well as the cases where a dual liability existed at the time of the ratification of the Paris Convention and the changes which have taken place since then are described. (NEA) [fr

  10. Magnetic field effects in hybrid perovskite devices

    Science.gov (United States)

    Zhang, C.; Sun, D.; Sheng, C.-X.; Zhai, Y. X.; Mielczarek, K.; Zakhidov, A.; Vardeny, Z. V.

    2015-05-01

    Magnetic field effects have been a successful tool for studying carrier dynamics in organic semiconductors as the weak spin-orbit coupling in these materials gives rise to long spin relaxation times. As the spin-orbit coupling is strong in organic-inorganic hybrid perovskites, which are promising materials for photovoltaic and light-emitting applications, magnetic field effects are expected to be negligible in these optoelectronic devices. We measured significant magneto-photocurrent, magneto-electroluminescence and magneto-photoluminescence responses in hybrid perovskite devices and thin films, where the amplitude and shape are correlated to each other through the electron-hole lifetime, which depends on the perovskite film morphology. We attribute these responses to magnetic-field-induced spin-mixing of the photogenerated electron-hole pairs with different g-factors--the Δg model. We validate this model by measuring large Δg (~ 0.65) using field-induced circularly polarized photoluminescence, and electron-hole pair lifetime using picosecond pump-probe spectroscopy.

  11. International co-operation in the nuclear field - past, present and prospects

    International Nuclear Information System (INIS)

    Goldschmidt, B.

    1978-01-01

    On the occasion of the 20th anniversary of its creation, the Nuclear Energy Agency of the Organization for Economic Co-operation and Development (NEA/OECD) held a symposium in Paris on 1 and 2 February 1978. Some 200 participants from the 23 Member countries of the NEA as well as representatives of the Commission of European Communities, FORATOM and the IAEA attended the symposium. At a panel discussion at the symposium, led by Dr. Sigvard Eklund, Director General of the IAEA, the future of international co-operation between advanced nations in the nuclear field was discussed. While recognizing that nuclear energy is at present going through a period of uncertainty pending resolution of the intertwined problems of gaining public confidence and of non-proliferation, the panel expressed its strong confidence in the future of nuclear power, and the vital contribution it would make, particularly between now and the end of the century. During the meeting, a critical review was made of the way in which international co-operation has evolved since the early stages of peaceful nuclear development, and of the influence on this co-operation of the changing relationship between government and industry. The contribution of international co-operation - and its limitations - was carefully scrutinized, notably in the crucial area of the nuclear fuel cycle

  12. Study of hydrogenated amorphous silicon devices under intense electric field: application to nuclear detection

    International Nuclear Information System (INIS)

    Ilie, A.

    1996-01-01

    The goal of this work was the study, development and optimization of hydrogenated amorphous silicon (a-Si:H) devices for use in detection of ionizing radiation in applications connected to the nuclear industry. Thick p-i-n devices, capable of withstanding large electric fields (up to 10 6 V/cm) with small currents (nA/cm 2 ), were proposed and developed. In order to decrease fabrication time, films were made using the 'He diluted' PECVD process and compared to standard a-Si:H films. Aspects connected to specific detector applications as well as to the fundamental physics of a-Si:H were considered: the internal electric field technique, in which the depletion charge was measured as a function of the applied bias voltage; study of the leakage current of p-i-n devices permitted us to demonstrate different regimes: depletion, field-enhanced thermal generation and electronic injection across the p layer. The effect of the electric field on the thermal generation of the carriers was studied considering the Poole-Frenkel and tunneling mechanisms. A model was developed taking under consideration the statistics of the correlated states and electron-phonon coupling. The results suggest that mechanisms not included in the 'standard model' of a Si:h need to be considered, such as defect relaxation, a filed-dependent mobility edge etc...; a new metastable phenomenon, called 'forming', induced by prolonged exposure to a strong electric field, was observed and studied. It is characterized by marked decrease of the leakage current and the detector noise, and increase in the breakdown voltage, as well as an improvement of carrier collection efficiency. This forming process appears to be principally due to an activation of the dopants in the p layer; finally, the capacity of thick p-i-n a Si:H devices to detect ionizing radiation has been evaluated. We show that it is possible, with 20-50 micron thick p-i-n devices, to detect the full spectrum of alpha and beta particles. With an

  13. Effect of δ meson and ρ-ω cross couplings in effective field theory motivated Lagrangian approach

    International Nuclear Information System (INIS)

    Jagota, R.K.; Dhiman, S.K.; Sharma, B.K.; Arumugam, P.; Patra, S.K.

    2005-01-01

    It is shown that the self and cross couplings of ω meson plays an important role to make the nuclear equation of state (EOS) softer. The parameter set G2, obtained from the effective field theory motivated Lagrangian (E-RMF) approach, is very successful to reproduce the nuclear matter properties including the structure of neutron star as well as of finite nuclei. The motivation of the present report is to see the effects of these terms in the E-RMF Lagrangian on infinite nuclear matter as well as finite nuclei

  14. Recursive polarization of nuclear spins in diamond at arbitrary magnetic fields

    International Nuclear Information System (INIS)

    Pagliero, Daniela; Laraoui, Abdelghani; Henshaw, Jacob D.; Meriles, Carlos A.

    2014-01-01

    We introduce an alternate route to dynamically polarize the nuclear spin host of nitrogen-vacancy (NV) centers in diamond. Our approach articulates optical, microwave, and radio-frequency pulses to recursively transfer spin polarization from the NV electronic spin. Using two complementary variants of the same underlying principle, we demonstrate nitrogen nuclear spin initialization approaching 80% at room temperature both in ensemble and single NV centers. Unlike existing schemes, our approach does not rely on level anti-crossings and is thus applicable at arbitrary magnetic fields. This versatility should prove useful in applications ranging from nanoscale metrology to sensitivity-enhanced NMR

  15. Guidance for Deployment of Mobile Technologies for Nuclear Power Plant Field Workers

    Energy Technology Data Exchange (ETDEWEB)

    Heather D. Medema; Ronald K. Farris

    2012-09-01

    This report is a guidance document prepared for the benefit of commercial nuclear power plants’ (NPPs) supporting organizations and personnel who are considering or undertaking deployment of mobile technology for the purpose of improving human performance and plant status control (PSC) for field workers in an NPP setting. This document especially is directed at NPP business managers, Electric Power Research Institute, Institute of Nuclear Power Operations, and other non-Information Technology personnel. This information is not intended to replace basic project management practices or reiterate these processes, but is to support decision-making, planning, and preparation of a business case.

  16. A compact HV supply for field/PC based nuclear instrumentation

    International Nuclear Information System (INIS)

    Manna, A.; Nikhare, D.M.; Madhavi, V.; Bayala, A.K.; Mukhopadhyay, P.K.; Kataria, S.K.

    2001-01-01

    In the recent years, most of the nuclear instruments that were earlier based on NIM Bin standards, are becoming available as PC Add-on cards. This trend is due to the decreasing prices of desktop personal computers and the necessity for automation in radioactivity measurements. This paper describes the design and development of a HV supply module and its PC Add-on card version for field portable/ PC based nuclear instrumentation. The HV supply though being very compact in size meets all the stringent specifications required for detector biasing applications and it has been tested for use with NaI, BF 3 . (author)

  17. In-situ measurement of environment radioactivity by mobile nuclear field laboratory (MNFL)

    International Nuclear Information System (INIS)

    Gopalani, Deepak; Mathur, A.P.; Rawat, D.K.; Barala, S.S.; Singhal, K.P.; Singh, G.P.; Samant, R.P.

    2008-01-01

    In-situ measurement of environment radioactivity is useful tool for determine the unusual increase of radioactivity at any place due to any nuclear eventuality take place. A mobile nuclear field laboratory has been designed and developed for in-situ measurement of environment radioactivity at any desired location. This vehicle is equipped with different monitoring and analysis instruments. These equipment can be operated while vehicle is moving. The measured data can be stored in computer. This vehicle has the space for storage of various environmental matrices of affected area and these can analysis in laboratory. (author)

  18. Nuclear power and the greenhouse effect

    International Nuclear Information System (INIS)

    Donaldson, D.M.; Tolland, H.G.

    1989-05-01

    Global levels of the ''Greenhouse'' gases - carbon dioxide, the chlorofluorocarbons (CFCs), methane, nitrous oxide and tropospheric ozone are increasing as a result of man's activities. This increase is widely expected to bring about a rise in global temperature with concomitant environmental impacts. Global warming has been observed over the last century, and the last decade has seen seven of the warmest years on record. There has also been increased variability in the weather (an expected consequence of global warming). However, these possible manifestations of the Greenhouse Effect are within natural variations and proof must await more definitive indications. A brief outline of current views on the Greenhouse Effect is given. This report addresses the energy sector using CO 2 emissions as a measure of its ''Greenhouse'' contribution. This approach understates the energy sector contribution. However, the difference is within the error band. It seems likely that the warming effect of non-energy related emissions will remain the same and there will be more pressure to reduce the emissions from the energy sector. To assess policy options the pattern of future energy demand is estimated. Two scenarios have been adopted to provide alternative frameworks. Both assume low energy growth projections based on increased energy efficiency. The role of nuclear power in reducing carbon dioxide emissions is considered. (author)

  19. Nanowire field effect transistors principles and applications

    CERN Document Server

    Jeong, Yoon-Ha

    2014-01-01

    “Nanowire Field Effect Transistor: Basic Principles and Applications” places an emphasis on the application aspects of nanowire field effect transistors (NWFET). Device physics and electronics are discussed in a compact manner, together with the p-n junction diode and MOSFET, the former as an essential element in NWFET and the latter as a general background of the FET. During this discussion, the photo-diode, solar cell, LED, LD, DRAM, flash EEPROM and sensors are highlighted to pave the way for similar applications of NWFET. Modeling is discussed in close analogy and comparison with MOSFETs. Contributors focus on processing, electrostatic discharge (ESD) and application of NWFET. This includes coverage of solar and memory cells, biological and chemical sensors, displays and atomic scale light emitting diodes. Appropriate for scientists and engineers interested in acquiring a working knowledge of NWFET as well as graduate students specializing in this subject.

  20. Will Iran Nuclear Deal Be Effectively Implemented?

    Institute of Scientific and Technical Information of China (English)

    Li Guofu

    2016-01-01

    The fourth Nuclear Security Summit is convened in Washington DC of the US on March 31st,2016.The development and utilization of nuclear energy has brought new power for the development of human society and significantly enhanced human capability of knowing and transforming the world.However,it also brought about nuclear security risks and challenge.Particularly in today’s international political struggle,some states are making use

  1. Influence of the nuclear Zeeman effect on mode locking in pulsed semiconductor quantum dots

    Science.gov (United States)

    Beugeling, Wouter; Uhrig, Götz S.; Anders, Frithjof B.

    2017-09-01

    The coherence of the electron spin in a semiconductor quantum dot is strongly enhanced by mode locking through nuclear focusing, where the synchronization of the electron spin to periodic pulsing is slowly transferred to the nuclear spins of the semiconductor material, mediated by the hyperfine interaction between these. The external magnetic field that drives the Larmor oscillations of the electron spin also subjects the nuclear spins to a Zeeman-like coupling, albeit a much weaker one. For typical magnetic fields used in experiments, the energy scale of the nuclear Zeeman effect is comparable to that of the hyperfine interaction, so that it is not negligible. In this work, we analyze the influence of the nuclear Zeeman effect on mode locking quantitatively. Within a perturbative framework, we calculate the Overhauser-field distribution after a prolonged period of pulsing. We find that the nuclear Zeeman effect can exchange resonant and nonresonant frequencies. We distinguish between models with a single type and with multiple types of nuclei. For the latter case, the positions of the resonances depend on the individual g factors, rather than on the average value.

  2. Study on the survey and analysis of education in the nuclear field

    International Nuclear Information System (INIS)

    Minguez, E.

    1998-01-01

    It has been identified on many occasions that human resources is one of the most important elements for nuclear energy deployment. Major activities include attracting sufficient number of bright and interested students to the field, and maintaining research activities for both current and future nuclear power utilisation, associated with the successful transfer of knowledge and know-how to the next generation. Even if some countries are not now developing additional nuclear power, there is a need for expertise in operating and then decommissioning existing plants and in radioactive waste management. Universities and in-house training which is provided by nuclear research institutes and companies, have both played significant roles in the history of nuclear development by educating and training young qualified people. It has been observed, however, that universities, nuclear programmes and courses are being merged with other subjects, or in the worst cases, simply closed down. The main reasons for this trend are that universities cannot maintain nuclear-related courses because of lack of students and budget cuts. Research institutes as well as private companies are facing similar budgetary constraints and they are also considerably diversifying into non-nuclear research fields. This loss of educational possibilities needs to be quantified so that governments can take a considered view as to need to remedy the situation. It would also be helpful to review actions already undertaken by governments, universities and research institutes to improve this situation. It should be noted that qualified manpower is a resource available for use on the global scale, even if supply tends to be matter for national decisions. An Expert Group has been created under the auspices of the Committee for Technical and Economic Studies on Nuclear Energy Development and Fuel Cycle (NDC) of the Nuclear Energy Agency (NEA) of the OECD. The Group consists of 24 experts from 17 Member countries

  3. Effective-field theories for heavy quarkonium

    International Nuclear Information System (INIS)

    Brambilla, Nora; Pineda, Antonio; Soto, Joan; Vairo, Antonio

    2005-01-01

    This article reviews recent theoretical developments in heavy-quarkonium physics from the point of view of effective-field theories of QCD. We discuss nonrelativistic QCD and concentrate on potential nonrelativistic QCD. The main goal will be to derive Schroedinger equations based on QCD that govern heavy-quarkonium physics in the weak- and strong-coupling regimes. Finally, the review discusses a selected set of applications, which include spectroscopy, inclusive decays, and electromagnetic threshold production

  4. Line broadening interference for high-resolution nuclear magnetic resonance spectra under inhomogeneous magnetic fields

    International Nuclear Information System (INIS)

    Wei, Zhiliang; Yang, Jian; Lin, Yanqin; Chen, Zhong; Chen, Youhe

    2015-01-01

    Nuclear magnetic resonance spectroscopy serves as an important tool for analyzing chemicals and biological metabolites. However, its performance is subject to the magnetic-field homogeneity. Under inhomogeneous fields, peaks are broadened to overlap each other, introducing difficulties for assignments. Here, we propose a method termed as line broadening interference (LBI) to provide high-resolution information under inhomogeneous magnetic fields by employing certain gradients in the indirect dimension to interfere the magnetic-field inhomogeneity. The conventional spectral-line broadening is thus interfered to be non-diagonal, avoiding the overlapping among adjacent resonances. Furthermore, an inhomogeneity correction algorithm is developed based on pattern recognition to recover the high-resolution information from LBI spectra. Theoretical deductions are performed to offer systematic and detailed analyses on the proposed method. Moreover, experiments are conducted to prove the feasibility of the proposed method for yielding high-resolution spectra in inhomogeneous magnetic fields

  5. Structure of neutron star crusts from new Skyrme effective interactions constrained by chiral effective field theory

    Science.gov (United States)

    Lim, Yeunhwan; Holt, Jeremy W.

    2017-06-01

    We investigate the structure of neutron star crusts, including the crust-core boundary, based on new Skyrme mean field models constrained by the bulk-matter equation of state from chiral effective field theory and the ground-state energies of doubly-magic nuclei. Nuclear pasta phases are studied using both the liquid drop model as well as the Thomas-Fermi approximation. We compare the energy per nucleon for each geometry (spherical nuclei, cylindrical nuclei, nuclear slabs, cylindrical holes, and spherical holes) to obtain the ground state phase as a function of density. We find that the size of the Wigner-Seitz cell depends strongly on the model parameters, especially the coefficients of the density gradient interaction terms. We employ also the thermodynamic instability method to check the validity of the numerical solutions based on energy comparisons.

  6. Nuclear shell effects at high temperatures

    International Nuclear Information System (INIS)

    Davidson, N.J.; Miller, H.G.

    1993-01-01

    In discussing the disappearance of nuclear shell effects at high temperatures, it is important to distinguish between the ''smearing out'' of the single-particle spectrum with increasing temperature and the vanishing of shell related structures in many-body quantities such as the excitation energy per nucleon. We propose a semiempirical method to obtain an upper bound on the temperature required to smooth the single-particle spectrum, and point out that shell effects in many-body parameters may persist above this temperature. We find that the temperature required to smear out the single-particle spectrum is approximately 1 MeV for heavy nuclei (A approx-gt 150) and about 3--4 MeV for light nuclei (A approx-lt 50), in reasonable agreement with the estimate of 41/πA 1/3 obtained from calculations with harmonic oscillator potentials. These temperatures correspond to many-body excitation energies of approximately 20 and 60 MeV, respectively

  7. Susceptibility effects in nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    Ziener, Christian Herbert

    2008-01-01

    The properties of dephasing and the resulting relaxation of the magnetization are the basic principle on which all magnetic resonance imaging methods are based. The signal obtained from the gyrating spins is essentially determined by the properties of the considered tissue. Especially the susceptibility differences caused by magnetized materials (for example, deoxygenated blood, BOLD-effect) or magnetic nanoparticles are becoming more important for biomedical imaging. In the present work, the influence of such field inhomogeneities on the NMR-signal is analyzed. (orig.)

  8. EU assistance for sustainable development of the nuclear field in Romania

    International Nuclear Information System (INIS)

    Geambasu, C.; Popadiuc, S.; Comsa, O.

    2006-01-01

    For Romania, the acceptance of the doctrine of sustainable development of the nuclear field represents the only responsible way of designing the development on medium and long term, according to the national interest and the requirements of international co-operation. Now, PHARE Program, as an opportunity for all Romanian power industry to join to EU requirements for integration, will continue to provide assistance to Romania for accelerating and completing preparations for its access to the European Union. Using EU assistance, Romania will achieve the main goals for the next years focused on: informing the officials, local administration and general public about nuclear power and its development, in direct connection with safety and environmental issues; promote new modern technologies in national industry, especially for building the second unit in Cernavoda; provide support for the national nuclear power program, according the EU integration tasks. Indicators of sustainable development in the energy sector are the subjects of present and future efforts within the EU. (author)

  9. New Developments of the Law of the Sea in the Nuclear Field

    International Nuclear Information System (INIS)

    Lampe, W.H.

    1977-01-01

    Following the 6th Session (July 1977) of the Conference on the Law of the Sea an Informal Composite Negotiating Text was released which has a direct bearing on several aspects of the peaceful uses of nuclear energy. These are, in particular, navigation of nuclear-powered merchant ships and their right of passage in territorial waters, their safety and the sea disposal of radioactive waste. It seems from the present status of the work of the Conference that the amendments likely to be made to the Law of the Sea will not impede the development of nuclear-powered navigation and the discussions stress the importance of the role international organisations should continue to play in this field. (NEA) [fr

  10. Radionuclide observables during the Integrated Field Exercise of the Comprehensive Nuclear-Test-Ban Treaty.

    Science.gov (United States)

    Burnett, Jonathan L; Miley, Harry S; Milbrath, Brian D

    2016-03-01

    In 2014 the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) undertook an Integrated Field Exercise (IFE14) in Jordan. The exercise consisted of a simulated 0.5-2 kT underground nuclear explosion triggering an On-site Inspection (OSI) to search for evidence of a Treaty violation. This research paper evaluates two of the OSI techniques used during the IFE14, laboratory-based gamma-spectrometry of soil samples and in-situ gamma-spectrometry, both of which were implemented to search for 17 OSI relevant particulate radionuclides indicative of nuclear explosions. The detection sensitivity is evaluated using real IFE and model data. It indicates that higher sensitivity laboratory measurements are the optimum technique during the IFE and within the Treaty/Protocol-specified OSI timeframes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Nuclear power's effects on electric rate making

    International Nuclear Information System (INIS)

    Smith, D.S.; Lancaster, A.A.

    1978-01-01

    Government and the electric utility industry are re-evaluating nuclear power's contribution to the total U.S. energy supplies. This article addresses how the recently increased nuclear plant construction and operation costs are translated into the prices that consumers pay for electricity. The electric rates that consumers pay must reflect the costs of producing electricity, as well as the costs of transmission, distribution, metering, and billing. The use of nuclear power for electric production is anticipated to grow rapidly so as to meet a larger portion of our country's electricity needs through the end of the century; so nuclear power costs are expected to be an even larger portion of the total electricity price. There are certain rate-making issues that are actively being discussed in public forums and before state and Federal regulatory bodies. These issues are not unique to nuclear power, but take on added significance when nuclear power is used by utilities to produce electricity because of the technology required and because of the type, timing, and magnitude of the costs involved. These are: (1) inclusion of construction work in progress in the rate base; (2) fuel adjustment clauses and treatment of nuclear fuel cycle costs; (3) treatment of certain taxes under the rate-making method called normalization or deferral accounting (sometimes referred to as ''phantom taxes''); and (4) rate treatment for particular nuclear expense items reflecting costs of delays, plant cancellations, and operational slowdowns

  12. Seismic effects on technological equipment and systems of nuclear power plants

    International Nuclear Information System (INIS)

    Masopust, R.; Pecinka, L.; Podrouzek, J.

    1983-01-01

    A survey is given of problems related to the construction of nuclear power plants with regard to seismic resistance. Sei--smic resistance of technological equipment is evaluated by experimental trials, calculation or the combination of both. Existing and future standards are given for the given field. The Czechoslovak situation is discussed as related to the construction of the Mochovce nuclear power plant. Procedures for testing seismic resistance, types of tests and methods of simulating seismic excitation are described. Antiseismic measures together with structural elements for limiting the seismic effects on technological equipment and nuclear power plant systems are summed up on the basis of foreign experience. (E.F.)

  13. Fringing field effects in negative capacitance field-effect transistors with a ferroelectric gate insulator

    Science.gov (United States)

    Hattori, Junichi; Fukuda, Koichi; Ikegami, Tsutomu; Ota, Hiroyuki; Migita, Shinji; Asai, Hidehiro; Toriumi, Akira

    2018-04-01

    We study the effects of fringing electric fields on the behavior of negative-capacitance (NC) field-effect transistors (FETs) with a silicon-on-insulator body and a gate stack consisting of an oxide film, an internal metal film, a ferroelectric film, and a gate electrode using our own device simulator that can properly handle the complicated relationship between the polarization and the electric field in ferroelectric materials. The behaviors of such NC FETs and the corresponding metal-oxide-semiconductor (MOS) FETs are simulated and compared with each other to evaluate the effects of the NC of the ferroelectric film. Then, the fringing field effects are evaluated by comparing the NC effects in NC FETs with and without gate spacers. The fringing field between the gate stack, especially the internal metal film, and the source/drain region induces more charges at the interface of the film with the ferroelectric film. Accordingly, the function of the NC to modulate the gate voltage and the resulting function to improve the subthreshold swing are enhanced. We also investigate the relationships of these fringing field effects to the drain voltage and four design parameters of NC FETs, i.e., gate length, gate spacer permittivity, internal metal film thickness, and oxide film thickness.

  14. Monitoring microbial growth and activity using spectral induced polarization and low-field nuclear magnetic resonance

    Science.gov (United States)

    Zhang, Chi; Keating, Kristina; Revil, Andre

    2015-04-01

    Microbes and microbial activities in the Earth's subsurface play a significant role in shaping subsurface environments and are involved in environmental applications such as remediation of contaminants in groundwater and oil fields biodegradation. Stimulated microbial growth in such applications could cause wide variety of changes of physical/chemical properties in the subsurface. It is critical to monitor and determine the fate and transportation of microorganisms in the subsurface during such applications. Recent geophysical studies demonstrate the potential of two innovative techniques, spectral induced polarization (SIP) and low-field nuclear magnetic resonance (NMR), for monitoring microbial growth and activities in porous media. The SIP measures complex dielectric properties of porous media at low frequencies of exciting electric field, and NMR studies the porous structure of geologic media and characterizes fluids subsurface. In this laboratory study, we examined both SIP and NMR responses from bacterial growth suspension as well as suspension mixed with silica sands. We focus on the direct contribution of microbes to the SIP and NMR signals in the absence of biofilm formation or biomineralization. We used Zymomonas mobilis and Shewanella oneidensis (MR-1) for SIP and NMR measurements, respectively. The SIP measurements were collected over the frequency range of 0.1 - 1 kHz on Z. mobilis growth suspension and suspension saturated sands at different cell densities. SIP data show two distinct peaks in imaginary conductivity spectra, and both imaginary and real conductivities increased as microbial density increased. NMR data were collected using both CPMG pulse sequence and D-T2 mapping to determine the T2-distribution and diffusion properties on S. oneidensis suspension, pellets (live and dead), and suspension mixed with silica sands. NMR data show a decrease in the T2-distribution in S. oneidensis suspension saturated sands as microbial density increase. A

  15. Radionuclide observables during the Integrated Field Exercise of the Comprehensive Nuclear-Test-Ban Treaty

    International Nuclear Information System (INIS)

    Burnett, Jonathan L.; Miley, Harry S.; Milbrath, Brian D.

    2016-01-01

    In 2014 the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) undertook an Integrated Field Exercise (IFE14) in Jordan. The exercise consisted of a simulated 0.5–2 kT underground nuclear explosion triggering an On-site Inspection (OSI) to search for evidence of a Treaty violation. This research paper evaluates two of the OSI techniques used during the IFE14, laboratory-based gamma-spectrometry of soil samples and in-situ gamma-spectrometry, both of which were implemented to search for 17 OSI relevant particulate radionuclides indicative of nuclear explosions. The detection sensitivity is evaluated using real IFE and model data. It indicates that higher sensitivity laboratory measurements are the optimum technique during the IFE and within the Treaty/Protocol-specified OSI timeframes. - Highlights: • The 2014 Integrated Field Exercise occurred in Jordan. • The detection sensitivity for two On-site Inspection techniques was evaluated. • The techniques search for 17 particulate radionuclides indicative of nuclear explosions. • Laboratory-based gamma-spectrometry of soil samples was the optimum technique.

  16. The Supersymmetric Effective Field Theory of Inflation

    Energy Technology Data Exchange (ETDEWEB)

    Delacrétaz, Luca V.; Gorbenko, Victor [Stanford Institute for Theoretical Physics, Stanford University,Stanford, CA 94306 (United States); Senatore, Leonardo [Stanford Institute for Theoretical Physics, Stanford University,Stanford, CA 94306 (United States); Kavli Institute for Particle Astrophysics and Cosmology, Stanford University and SLAC,Menlo Park, CA 94025 (United States)

    2017-03-10

    We construct the Supersymmetric Effective Field Theory of Inflation, that is the most general theory of inflationary fluctuations when time-translations and supersymmetry are spontaneously broken. The non-linear realization of these invariances allows us to define a complete SUGRA multiplet containing the graviton, the gravitino, the Goldstone of time translations and the Goldstino, with no auxiliary fields. Going to a unitary gauge where only the graviton and the gravitino are present, we write the most general Lagrangian built out of the fluctuations of these fields, invariant under time-dependent spatial diffeomorphisms, but softly-breaking time diffeomorphisms and gauged SUSY. With a suitable Stückelberg transformation, we introduce the Goldstone boson of time translation and the Goldstino of SUSY. No additional dynamical light field is needed. In the high energy limit, larger than the inflationary Hubble scale for the Goldstino, these fields decouple from the graviton and the gravitino, greatly simplifying the analysis in this regime. We study the phenomenology of this Lagrangian. The Goldstino can have a non-relativistic dispersion relation. Gravitino and Goldstino affect the primordial curvature perturbations at loop level. The UV modes running in the loops generate three-point functions which are degenerate with the ones coming from operators already present in the absence of supersymmetry. Their size is potentially as large as corresponding to f{sub NL}{sup equil.,orthog.}∼1 or, for particular operators, even ≫1. The non-degenerate contribution from modes of order H is estimated to be very small.

  17. Effective field theories for correlated electrons

    International Nuclear Information System (INIS)

    Wallington, J.P.

    1999-10-01

    In this thesis, techniques of functional integration are applied to the construction of effective field theories for models of strongly correlated electrons. This is accomplished by means of the Hubbard-Stratonovic transformation which maps a system of interacting fermions onto one of free fermions interacting, not with each other, but with bosonic fields representing the collective modes of the system. Different choices of transformation are investigated throughout the thesis. It is shown that there exists a new group of discrete symmetries and transformations of the Hubbard model. Using this new group, the problem of choosing a Hubbard-Stratonovic decomposition of the Hubbard interaction term is solved. In the context of the exotic doped barium bismuthates, an extended Hubbard model with on-site attraction and nearest neighbour repulsion is studied. Mean field and renormalisation group analyses show a 'pseudospin-flop' from charge density wave to superconductivity as a function of filling. The nearest neighbour attractive Hubbard model on a quasi-2D lattice is studied as a simple phenomenological model for the high-T c cuprates. Mean field theory shows a transition from pure d-wave to pure s-wave superconductivity, via a mixed symmetry s + id state. Using Gaussian fluctuations, the BCS-Bose crossover is examined and suggestions are made about the origin of the angle dependence of the pseudogap. The continuum delta-shell potential model is introduced for anisotropic superconductors. Its mean field phases are studied and found to have some unusual properties. The BCS-Bose crossover is examined and the results are compared with those of the lattice model. Quasi-2D (highly anisotropic 3D) systems are considered. The critical properties of a Bose gas are investigated as the degree of anisotropy is varied. A new 2D Bose condensate state is found. A renormalisation group analysis is used to investigate the crossover from 2D to 3D. (author)

  18. Lateral Flow Field Behavior Downstream of Mixing Vanes In a Simulated Nuclear Fuel Rod Bundle

    International Nuclear Information System (INIS)

    Conner, Michael E.; Smith, L. David III; Holloway, Mary V.; Beasley, Donald E.

    2004-01-01

    To assess the fuel assembly performance of PWR nuclear fuel assemblies, average subchannel flow values are used in design analyses. However, for this highly complex flow, it is known that local conditions around fuel rods vary dependent upon the location of the fuel rod in the fuel assembly and upon the support grid design that maintains the fuel rod pitch. To investigate the local flow in a simulated nuclear fuel rod bundle, a testing technique has been employed to measure the lateral flow field in a 5 x 5 rod bundle. Particle Image Velocimetry was used to measure the lateral flow field downstream of a support grid with mixing vanes for four unique subchannels in the 5 x 5 bundle. The dominant lateral flow structures for each subchannel are compared in this paper including the decay of these flow structures. (authors)

  19. Evaluation of poly(vinylpyrrolidone) and collagen by Low Field Nuclear Magnetic Resonance Spectroscopy

    International Nuclear Information System (INIS)

    Costa, Paula de M.; Tavares, Maria I.B.

    2005-01-01

    Blends of natural and synthetic polymers represent a new class of materials with better mechanical properties and biocompatibility than those of the single components. Collagen and poly(vinylpyrrolidone) are well known for their important biological properties. The blending of collagen with poly(vinylpyrrolidone) makes it possible to obtain new materials in which strong interactions between the synthetic and biological components occur. Do to the excellent biocompatibility of these polymers, this blend has been much studied intending biomedical applications. And a one technique that can provide important information on molecular mobility, compatibility and even evaluate the interactions that can occur with these polymers is the Low Field Nuclear Magnetic Resonance Spectroscopy. Thus, the purpose of this work is to evaluate collagen and poly(vinylpyrrolidone) by Low Field Nuclear Magnetic Resonance Spectroscopy. From the values of relaxation times obtained, we can conclude that these materials have different interactions, and different mobility domains, confirming the heterogeneity and complexity of these materials. (author)

  20. Relativistic mean-field approximation with density-dependent screening meson masses in nuclear matter

    International Nuclear Information System (INIS)

    Sun, Baoxi; Lu, Xiaofu; Shen, Pengnian; Zhao, Enguang

    2003-01-01

    The Debye screening masses of the σ, ω and neutral ρ mesons and the photon are calculated in the relativistic mean-field approximation. As the density of the nucleon increases, all the screening masses of mesons increase. A different result with Brown–Rho scaling is shown, which implies a reduction in the mass of all the mesons in the nuclear matter, except the pion. Replacing the masses of the mesons with their corresponding screening masses in the Walecka-1 model, five saturation properties of the nuclear matter are fixed reasonably, and then a density-dependent relativistic mean-field model is proposed without introducing the nonlinear self-coupling terms of mesons. (author)