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.)
A Review of Target Mass Corrections
Energy Technology Data Exchange (ETDEWEB)
I. Schienbein; V. Radescu; G. Zeller; M. E. Christy; C. E. Keppel; K. S. McFarland; W. Melnitchouk; F. I. Olness; M. H. Reno; F. Steffens; J.-Y. Yu
2007-09-06
With recent advances in the precision of inclusive lepton-nuclear scattering experiments, it has become apparent that comparable improvements are needed in the accuracy of the theoretical analysis tools. In particular, when extracting parton distribution functions in the large-x region, it is crucial to correct the data for effects associated with the nonzero mass of the target. We present here a comprehensive review of these target mass corrections (TMC) to structure functions data, summarizing the relevant formulas for TMCs in electromagnetic and weak processes. We include a full analysis of both hadronic and partonic masses, and trace how these effects appear in the operator product expansion and the factorized parton model formalism, as well as their limitations when applied to data in the x -> 1 limit. We evaluate the numerical effects of TMCs on various structure functions, and compare fits to data with and without these corrections.
Electromagnetic corrections to baryon masses
International Nuclear Information System (INIS)
Durand, Loyal; Ha, Phuoc
2005-01-01
We analyze the electromagnetic contributions to the octet and decuplet baryon masses using the heavy-baryon approximation in chiral effective field theory and methods we developed in earlier analyses of the baryon masses and magnetic moments. Our methods connect simply to Morpurgo's general parametrization of the electromagnetic contributions and to semirelativistic quark models. Our calculations are carried out including the one-loop mesonic corrections to the basic electromagnetic interactions, so to two loops overall. We find that to this order in the chiral loop expansion there are no three-body contributions. The Coleman-Glashow relation and other sum rules derived in quark models with only two-body terms therefore continue to hold, and violations involve at least three-loop processes and can be expected to be quite small. We present the complete formal results and some estimates of the matrix elements here. Numerical calculations will be presented separately
Stanke, Monika; Bralin, Amir; Bubin, Sergiy; Adamowicz, Ludwik
2018-01-01
In this work we report progress in the development and implementation of quantum-mechanical methods for calculating bound ground and excited states of small atomic systems. The work concerns singlet states with the L =1 total orbital angular momentum (P states). The method is based on the finite-nuclear-mass (non-Born-Oppenheimer; non-BO) approach and the use of all-particle explicitly correlated Gaussian functions for expanding the nonrelativistic wave function of the system. The development presented here includes derivation and implementation of algorithms for calculating the leading relativistic corrections for singlet states. The corrections are determined in the framework of the perturbation theory as expectation values of the corresponding effective operators using the non-BO wave functions. The method is tested in the calculations of the ten lowest 1P states of the helium atom and the four lowest 1P states of the beryllium atom.
Charm mass corrections to the bottomonium mass spectrum
International Nuclear Information System (INIS)
Ebert, D.; Faustov, R. N.; Galkin, V. O.
2002-01-01
The one-loop corrections to the bottomonium mass spectrum due to the finite charm mass are evaluated in the framework of the relativistic quark model. The obtained corrections are compared with the results of perturbative QCD
Mass corrections in deep-inelastic scattering
International Nuclear Information System (INIS)
Gross, D.J.; Treiman, S.B.; Wilczek, F.A.
1977-01-01
The moment sum rules for deep-inelastic lepton scattering are expected for asymptotically free field theories to display a characteristic pattern of logarithmic departures from scaling at large enough Q 2 . In the large-Q 2 limit these patterns do not depend on hadron or quark masses m. For modest values of Q 2 one expects corrections at the level of powers of m 2 /Q 2 . We discuss the question whether these mass effects are accessible in perturbation theory, as applied to the twist-2 Wilson coefficients and more generally. Our conclusion is that some part of the mass effects must arise from a nonperturbative origin. We also discuss the corrections which arise from higher orders in perturbation theory for very large Q 2 , where mass effects can perhaps be ignored. The emphasis here is on a characterization of the Q 2 , x domain where higher-order corrections are likely to be unimportant
The art of predicting nuclear masses
International Nuclear Information System (INIS)
Hirsch, J.G.; Morales, I.; Mendoza-Temis, J.; Frank, A.; Lopez-Vieyra, J.C.; Barea, J.; Pittel, S.; Van Isacker, P.; Velazquez, V.
2008-01-01
A review of recent advances in the theoretical analysis of nuclear mass models and their predictive power is presented. After introducing two tests which probe the ability of nuclear mass models to extrapolate, three models are analyzed in detail: the liquid drop model (LDM), the liquid drop model plus empirical shell corrections (LDMM) and the Duflo–Zuker mass formula (DZ). The DZ model is exhibited as the most predictive model. The Garvey–Kelson mass relations are also discussed. It is shown that their fulfillment probes the consistency of the most commonly used mass formulae, and that they can be used in an iterative process to predict nuclear masses in the neighborhood of nuclei with measured masses, offering a simple and reproducible procedure for short range mass predictions. (author)
Quantum chaos and nuclear mass systematics
International Nuclear Information System (INIS)
Hirsch, Jorge G.; Velazquez, Victor; Frank, Alejandro
2004-01-01
The presence of quantum chaos in nuclear mass systematics is analyzed by considering the differences between measured and calculated nuclear masses as a time series described by the power law 1fα. While for the liquid droplet model plus shell corrections a quantum chaotic behavior α∼1 is found, errors in the microscopic mass formula have α∼0.5, closer to white noise. The chaotic behavior seems to arise from many body effects not included in the mass formula
Quark mass correction to the string potential
International Nuclear Information System (INIS)
Lambiase, G.; Nesterenko, V.V.
1995-01-01
A consistent method for calculating the interquark potential generated by the relativistic string with massive ends is proposed. In this approach the interquark potential in the model of the Nambu-Goto string with point-like masses at its ends is calculated. At first the calculation is done in the one-loop approximation and then the variational estimation is performed. The quark mass correction results in decreasing the critical distance (deconfinement radius). When quark mass decreases the critical distance also decreases. For obtaining a finite result under summation over eigenfrequencies of the Nambu-Goto string with massive ends a suitable mode-by-mode subtraction is proposed. This renormalization procedure proves to be completely unique. In the framework of the developed approach the one-loop interquark potential in the model of the relativistic string with rigidity is also calculated. 34 refs., 2 figs
Correcting mass shifts: A lock mass-free recalibration procedure for mass spectrometry imaging data
Czech Academy of Sciences Publication Activity Database
Kulkarni, P.; Kaftan, F.; Kynast, P.; Svatoš, Aleš; Böcker, S.
2015-01-01
Roč. 407, č. 25 (2015), s. 7603-7613 ISSN 1618-2642 Institutional support: RVO:61388963 Keywords : mass spectrometry imaging * recalibration * mass shift correction * data processing Subject RIV: CB - Analytical Chemistry , Separation Impact factor: 3.125, year: 2015
Mass corrections to Green functions in instanton vacuum model
International Nuclear Information System (INIS)
Esaibegyan, S.V.; Tamaryan, S.N.
1987-01-01
The first nonvanishing mass corrections to the effective Green functions are calculated in the model of instanton-based vacuum consisting of a superposition of instanton-antiinstanton fluctuations. The meson current correlators are calculated with account of these corrections; the mass spectrum of pseudoscalar octet as well as the value of the kaon axial constant are found. 7 refs
Hadron mass corrections in semi-inclusive deep inelastic scattering
International Nuclear Information System (INIS)
Accardi, A.; Hobbs, T.; Melnitchouk, W.
2009-01-01
We derive mass corrections for semi-inclusive deep inelastic scattering of leptons from nucleons using a collinear factorization framework which incorporates the initial state mass of the target nucleon and the final state mass of the produced hadron h. The hadron mass correction is made by introducing a generalized, finite-Q 2 scaling variable ζ h for the hadron fragmentation function, which approaches the usual energy fraction z h = E h /ν in the Bjorken limit. We systematically examine the kinematic dependencies of the mass corrections to semi-inclusive cross sections, and find that these are even larger than for inclusive structure functions. The hadron mass corrections compete with the experimental uncertainties at kinematics typical of current facilities, Q 2 2 and intermediate x B > 0.3, and will be important to efforts at extracting parton distributions from semi-inclusive processes at intermediate energies.
Testing the predictive power of nuclear mass models
International Nuclear Information System (INIS)
Mendoza-Temis, J.; Morales, I.; Barea, J.; Frank, A.; Hirsch, J.G.; Vieyra, J.C. Lopez; Van Isacker, P.; Velazquez, V.
2008-01-01
A number of tests are introduced which probe the ability of nuclear mass models to extrapolate. Three models are analyzed in detail: the liquid drop model, the liquid drop model plus empirical shell corrections and the Duflo-Zuker mass formula. If predicted nuclei are close to the fitted ones, average errors in predicted and fitted masses are similar. However, the challenge of predicting nuclear masses in a region stabilized by shell effects (e.g., the lead region) is far more difficult. The Duflo-Zuker mass formula emerges as a powerful predictive tool
Mass and Inertia Parameters for Nuclear Fission
International Nuclear Information System (INIS)
Damgaard, J.; Pauli, H.C.; Strutinsky, V.M.; Wong, C.Y.; Brack, M.; Stenholm-Jensen, A.
1969-01-01
The effective mass parameter and the moments of inertia for a deformed nucleus are evaluated using the cranking-model formalism. Special attention is paid to the dependence of these quantities on the intrinsic structure, which may arise due to shells in deformed nuclei. It is found that these inertial parameters are very much influenced by the shells present. The effective-mass parameter, which appears in an important way in the theory of spontaneous fission, fluctuates in the same manner as the shell-energy corrections. Its values at the fission barrier are up to two or three times larger than those at the equilibrium minima. This correlation comes about because for the effective mass the change in the local density of single-particle states is very important, much more so than the change in the pairing correlation. The moments of inertia which enter in the theory of angular anisotropy of fission fragments, also fluctuate as a function of the deformation. At low temperatures, the fluctuation is large and shows a distinct but more complicated correlation with the shells. At high temperatures, the moments of inertia fluctuate with a smaller amplitude about the rigid-body value in correlation with the energy-shell corrections. For the first-and second barriers, the rigid-body values are essentially reached at a nuclear temperature of 0.8 to 1.0 MeV. (author)
Radiative corrections to the masses of supersymmetric Higgs bosons
International Nuclear Information System (INIS)
Ellis, J.; Zwirner, F.
1991-01-01
The lightest neutral Higgs boson in the minimal supersymmetric extension of the standard model has a tree-level mass less than that of the Z 0 . We calculate radiative corrections to its mass and to that of the heavier CP-even neutral Higgs boson. We find large corrections that increase with the top quark and squark masses, and vary with the ratio of vacuum expectation values v 2 /v 1 . These radiative corrections can be as large as O(100) GeV, and have the effect of (i) invalidating lower bounds on v 2 /v 1 inferred from unsuccessful Higgs searches at LEP I, (ii) in many cases, increasing the mass of the lighter CP-even Higgs boson beyond m z , (iii) often, increasing the mass of the heavier CP-even Higgs boson beyond the LEP reach, into a range more accessible to the LHC or SSC. (orig.)
Nuclear enhanced power corrections to DIS structure functions
Guo, Xiaofeng; Qiu, Jianwei; Zhu, Wei
2001-01-01
We calculate nuclear enhanced power corrections to structure functions measured in deeply inelastic lepton-nucleus scattering in Quantum Chromodynamics (QCD). We find that the nuclear medium enhanced power corrections at order of $O(\\alpha_s/Q^2)$ enhance the longitudinal structure function $F_L$, and suppress the transverse structure function $F_1$. We demonstrate that strong nuclear effects in $\\sigma_A/\\sigma_D$ and $R_A/R_D$, recently observed by HERMES Collaboration, can be explained in ...
Physical matrix correction for RFA of mass and special glasses
International Nuclear Information System (INIS)
Medicus, G.; Ritter, R.
1984-01-01
A theoretical matrix correction model with relatively complex mass absorption coefficients is reported, which takes into account the adsorption of the stimulating radiation and the radiation in the specimen to be measured, as well as the geometry of the spectrometer. With the realized concept of an effective primary wave length, good correction results were obtained over large regions of concentrations and elements. The computer program renders possible besides of the usual reference measurement at uniform reference wave length - the reference of several elements in the specimen to one special element of the reference specimen. The correction method was tested with 42 test glasses, which were previously analyzed. (author)
Dynamic retardation corrections to the mass spectrum of heavy quarkonia
International Nuclear Information System (INIS)
Kopalejshvili, T.; Rusetskij, A.
1996-01-01
In the framework of the Logunov-Tavkhelidze quasipotential approach the first-order retardation corrections to the heavy quarkonia mass spectrum are calculated with the use of the stationary wave boundary condition in the covariant kernel of the Bethe-Salpeter equation. As has been expected, these corrections turn out to be small for all low-lying heavy meson states and vanish in the heavy quark limit (m Q →∞). The comparison of the suggested approach to the calculation of retardation corrections with others, known in literature, is carried out. 22 refs., 1 tab
Critical assessment of nuclear mass models
International Nuclear Information System (INIS)
Moeller, P.; Nix, J.R.
1992-01-01
Some of the physical assumptions underlying various nuclear mass models are discussed. The ability of different mass models to predict new masses that were not taken into account when the models were formulated and their parameters determined is analyzed. The models are also compared with respect to their ability to describe nuclear-structure properties in general. The analysis suggests future directions for mass-model development
Quark mass correction to chiral separation effect and pseudoscalar condensate
Energy Technology Data Exchange (ETDEWEB)
Guo, Er-dong [State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics,Chinese Academy of Sciences,Beijing 100190 (China); Kavli Institute of Theoretical Physics China, Chinese Academy of Sciences,Beijing 100190 (China); Lin, Shu [School of Physics and Astronomy, Sun Yat-Sen University,No 2 University Road, Zhuhai 519082 (China)
2017-01-25
We derived an analytic structure of the quark mass correction to chiral separation effect (CSE) in small mass regime. We confirmed this structure by a D3/D7 holographic model study in a finite density, finite magnetic field background. The quark mass correction to CSE can be related to correlators of pseudo-scalar condensate, quark number density and quark condensate in static limit. We found scaling relations of these correlators with spatial momentum in the small momentum regime. They characterize medium responses to electric field, inhomogeneous quark mass and chiral shift. Beyond the small momentum regime, we found existence of normalizable mode, which possibly leads to formation of spiral phase. The normalizable mode exists beyond a critical magnetic field, whose magnitude decreases with quark chemical potential.
Relativistic corrections to the Cooperon mass: BCS versus BEC picture
Energy Technology Data Exchange (ETDEWEB)
Lipavský, P., E-mail: lipavsky@karlov.mff.cuni.cz
2017-02-15
Highlights: • Tate's measurement of relativistic effects on the Cooper pair mass show the increase while a decrease was expected. • This disagreement raised a question whether it has fundamental significance or is due to the details of the particular physical system being studied. • The most fundamental were speculations about gravitomagnetic forces enhanced by the Higgs mechanism. • These were recently disproved experimentally. • This paper shows that the relativistic mass corrections might be sensitive to the pairing scenario: the predicted mass decrease corresponds to the Bose–Einstein condensation of preformed Cooper pairs, while the pairing in the Bardeen–Cooper–Schrieffer condensate leads to an increase of experimentally observed magnitude. - Abstract: Relativistic corrections to the Cooperon mass are discussed for preformed Cooper pairs that become superconductive via the Bose–Einstein condensation (BEC) and for Cooperons in the Bardeen–Copper–Schrieffer (BCS) condensate. The distinction explains experimental results of Tate et al. (1989).
Nuclear Quantum Gravitation - The Correct Theory
Kotas, Ronald
2016-03-01
Nuclear Quantum Gravitation provides a clear, definitive Scientific explanation of Gravity and Gravitation. It is harmonious with Newtonian and Quantum Mechanics, and with distinct Scientific Logic. Nuclear Quantum Gravitation has 10 certain, Scientific proofs and 21 more good indications. With this theory the Physical Forces are obviously Unified. See: OBSCURANTISM ON EINSTEIN GRAVITATION? http://www.santilli- Foundation.org/inconsistencies-gravitation.php and Einstein's Theory of Relativity versus Classical Mechanics http://www.newtonphysics.on.ca/einstein/
Systematics of nuclear mass and level density formulas
Energy Technology Data Exchange (ETDEWEB)
Nakamura, Hisashi [Fuji Electric Co. Ltd., Kawasaki, Kanagawa (Japan)
1998-03-01
The phenomenological models of the nuclear mass and level density are close related to each other, the nuclear ground and excited state properties are described by using the parameter systematics on the mass and level density formulas. The main aim of this work is to provide in an analytical framework the improved energy dependent shell, pairing and deformation corrections generalized to the collective enhancement factors, which offer a systematic prescription over a great number of nuclear reaction cross sections. The new formulas are shown to be in close agreement with not only the empirical nuclear mass data but the measured slow neutron resonance spacings, and experimental systematics observed in the excitation energy dependent properties. (author)
Economic benefits of power factor correction at a nuclear facility
International Nuclear Information System (INIS)
Boger, R.M.; Dalos, W.; Juguilon, M.E.
1986-01-01
The economic benefits of correcting poor power factor at an operating nuclear facility are shown. A project approach for achieving rapid return of investment without disrupting plant availability is described. Examples of technical problems associated with using capacitors for power factor correction are presented
A radiative corrections scheme for generation of the lepton masses
International Nuclear Information System (INIS)
Pisano, F.; Pleitez, V.; Tonasse, M.D.
1994-01-01
We consider in the context of 331 model of the electroweak interactions the generation of the lepton masses by introducing a single neutral right-handed singlet in a radiatively corrections scheme. By adding a lepton-baryon number violating term in the Higgs potential, we show that one can have the right mass spectrum for the leptons without introducing a sextet of Higgs fields which is present in the original model. (author) of Higgs fields which is present in the original model. (author)
Next-to leading order analysis of target mass corrections to structure functions and asymmetries
International Nuclear Information System (INIS)
Brady, L.T.; Accardi, A.; Hobbs, T.J.; Melnitchouk, W.
2011-01-01
We perform a comprehensive analysis of target mass corrections (TMCs) to spin-averaged structure functions and asymmetries at next-to-leading order. Several different prescriptions for TMCs are considered, including the operator product expansion, and various approximations to it, collinear factorization, and xi-scaling. We assess the impact of each of these on a number of observables, such as the neutron to proton F 2 structure function ratio, and parity-violating electron scattering asymmetries for protons and deuterons which are sensitive to gamma-Z interference effects. The corrections from higher order radiative and nuclear effects on the parity-violating deuteron asymmetry are also quantified.
Mass corrections in string theory and lattice field theory
International Nuclear Information System (INIS)
Del Debbio, Luigi; Kerrane, Eoin; Russo, Rodolfo
2009-01-01
Kaluza-Klein (KK) compactifications of higher-dimensional Yang-Mills theories contain a number of 4-dimensional scalars corresponding to the internal components of the gauge field. While at tree level the scalar zero modes are massless, it is well known that quantum corrections make them massive. We compute these radiative corrections at 1 loop in an effective field theory framework, using the background field method and proper Schwinger-time regularization. In order to clarify the proper treatment of the sum over KK modes in the effective field theory approach, we consider the same problem in two different UV completions of Yang-Mills: string theory and lattice field theory. In both cases, when the compactification radius R is much bigger than the scale of the UV completion (R>>√(α ' ), a), we recover a mass renormalization that is independent of the UV scale and agrees with the one derived in the effective field theory approach. These results support the idea that the value of the mass corrections is, in this regime, universal for any UV completion that respects locality and gauge invariance. The string analysis suggests that this property holds also at higher loops. The lattice analysis suggests that the mass of the adjoint scalars appearing in N=2, 4 super Yang-Mills is highly suppressed, even if the lattice regularization breaks all supersymmetries explicitly. This is due to an interplay between the higher-dimensional gauge invariance and the degeneracy of bosonic and fermionic degrees of freedom.
Plasma Mass Filters For Nuclear Waste Reprocessing
International Nuclear Information System (INIS)
Fetterman, Abraham J.; Fisch, Nathaniel J.
2011-01-01
Practical disposal of nuclear waste requires high-throughput separation techniques. The most dangerous part of nuclear waste is the fission product, which contains the most active and mobile radioisotopes and produces most of the heat. We suggest that the fission products could be separated as a group from nuclear waste using plasma mass filters. Plasmabased processes are well suited to separating nuclear waste, because mass rather than chemical properties are used for separation. A single plasma stage can replace several stages of chemical separation, producing separate streams of bulk elements, fission products, and actinoids. The plasma mass filters may have lower cost and produce less auxiliary waste than chemical processing plants. Three rotating plasma configurations are considered that act as mass filters: the plasma centrifuge, the Ohkawa filter, and the asymmetric centrifugal trap.
Nuclear power plant cost underestimation: mechanisms and corrections
International Nuclear Information System (INIS)
Meyer, M.B.
1984-01-01
Criticisms of inaccurate nuclear power plant cost estimates have commonly focused upon what factors have caused actual costs to increase and not upon the engineering cost estimate methodology itself. This article describes two major sources of cost underestimation and suggests corrections for each which can be applied while retaining the traditional engineering methodology in general
One-loop corrections to classical masses of kink families
International Nuclear Information System (INIS)
Alonso Izquierdo, A.; Garcia Fuertes, W.; Gonzalez Leon, M.A.; Mateos Guilarte, J.
2004-01-01
One-loop corrections to kink masses in a family of (1+1)-dimensional field theoretical models with two real scalar fields are computed. A generalized DHN formula applicable to potentials with and without reflection is obtained. It is shown how half-bound states arising in the spectrum of the second-order fluctuation operator for one-component topological kinks and the vacuum play a central role in the computation of the kink Casimir energy. The issue of whether or not the kink degeneracy exhibited by this family of models at the classical level survives one-loop quantum fluctuations is addressed
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.)
Mass Spectrometric Analysis for Nuclear Safeguards
International Nuclear Information System (INIS)
Boulyga, S.
2013-01-01
The release of man-made radionuclides into the environment results in contamination that carries specific isotopic signatures according to the release scenarios and the previous usage of materials and facilities. In order to trace the origin of such contamination and/or to assess the potential impact on the public and environmental health, it is necessary to determine the isotopic composition and activity concentrations of radionuclides in environmental samples in an accurate and timely fashion. Mass spectrometric techniques, such as thermal ionization mass spectrometry (TIMS), secondary ion mass spectrometry (SIMS), and inductively coupled plasma mass spectrometry (ICP-MS) belong to the most powerful methods for analysis of nuclear and related samples in nuclear safeguards, forensics, and environmental monitoring. This presentation will address the potential of mass spectrometric analysis of actinides at ultra-trace concentration levels, isotopic analysis of micro-samples, age determination of nuclear materials as well as identification and quantification of elemental and isotopic signatures of nuclear samples in general. (author)
Mass spectrometry in nuclear science and technology
International Nuclear Information System (INIS)
Komori, Takuji
1985-01-01
Mass spectrometry has been widely used and playing a very important role in the field of nuclear science and technology. A major reason for this is that not only the types of element but also its isotopes have to be identified and measured in this field. Thus, some applications of this analytical method are reviewed and discussed in this article. Its application to analytical chemistry is described in the second section following an introductory section, which includes subsections for isotropic dilution mass spectrometry, resonance ionization mass spectrometry and isotopic correlation technique. The isotopic ratio measurement for hydrogen, uranium and plutonium as well as nuclear material control and safeguards are also reviewed in this section. In the third section, mass spectrometry is discussed in relation to nuclear reactors, with subsections on natural uranium reactor and neutron flux observation. Some techniques for measuring the burnup fraction, including the heavy isotopic ratio method and fission product monitoring, are also described. In the fourth section, application of mass spectrometry to measurement of nuclear constants, such as ratio of effective cross-sectional area for 235 U, half-life and fission yield is reviewed. (Nogami, K.)
Correction factors for photon spectrometry in nuclear parameters study
International Nuclear Information System (INIS)
Patrao, Karla Cristina de Souza
2004-10-01
The goal of this work was the determination, using metrologic severity, the factors of correction for coincidences XX, Xγ and γγ and the factors of transference of efficiency for use in gamma spectrometry. On this way, it was carried through by determination of nuclear parameters of a nuclide used in medicine diagnostic ( 201 Tl) and the standardization of two environmental samples, of regular and irregular geometry, proceeding from the residual (ashes and slag) from the nuclear industry. The results shows that this adopted methodology is valid, and it allows its application for many different nuclides, including complex decay schema nuclides, using only photons spectrometry techniques on semiconductor detectors. (author)
Mass spectrometric analysis for nuclear safeguards
BOULYGA S.; KONEGGER-KAPPEL S.; RICHTER Stephan; SANGELY L.
2014-01-01
Mass spectrometry is currently being implemented in a wide spectrum of research and industrial areas, such as material sciences, cosmo- and geochemistry, biology and medicine, to name just a few. Research and development in nuclear safeguards is closely related to the general field of “Peace Research”; representing a specific application area for analytical sciences in general and for mass spectrometry in particular. According to Albert Einstein “peace cannot be kept by force. It only can be ...
Effective corrective actions to enhance operational safety of nuclear installations
International Nuclear Information System (INIS)
2005-07-01
The safe operation of nuclear power plants around the world and the prevention of incidents in these installations remain key concerns for the nuclear community. In this connection the feedback of operating experience plays a major role: every nuclear plant operator needs to have a system in place to identify and feed back the lessons learned from operating experience and to implement effective corrective actions to prevent safety events from reoccurring. An effective operating experience programme also includes a proactive approach that is aimed at preventing the first-time occurrence of safety events. In April 2003, the IAEA issued the PROSPER guidelines for nuclear installations to strengthen and enhance their own operating experience process and for self-assessment on the effectiveness of the feedback process. Subsequently, in the course of the Operational Safety Review Teams missions conducted by the IAEA that focused on the operational safety practices of nuclear power plants, the IAEA enhanced the review of the operating experience in nuclear power plants by implementing a new module that is derived from these guidelines. In order to highlight the effective implementation of the operating experience programme and to provide practical assistance in this area, the IAEA organized workshops and conferences to discuss recent trends in operating experience. The IAEA also performed assistance and review missions at plants and corporate organizations. The IAEA is further developing advice and assistance on operating experience feedback programmes and is reporting on good practices. The present publication is the outcome of two years of coordinated effort involving the participation of experts of nuclear organizations in several Member States. It provides information and good practices for successfully establishing an effective corrective actions programme. This publication forms part of a series that develops the principles set forth in these guidelines
Mass-spectrometric measurements for nuclear safeguards
International Nuclear Information System (INIS)
Carter, J.A.; Smith, D.H.; Walker, R.L.
1982-01-01
The need of an on-site inspection device to provide isotopic ratio measurements led to the development of a quadrupole mass spectrometer mounted in a van. This mobile laboratory has the ability, through the use of the resin bead technique, to acquire, prepare, and analyze samples of interest to nuclear safeguards. Precision of the measurements is about 1 to 2%
Correcting environmental problems facing the nuclear weapons complex
International Nuclear Information System (INIS)
Rezendes, V.S.
1990-06-01
This report discusses DOE's efforts to correct the environmental problems facing the nuclear weapons complex. It focuses on three main points. First, the weapons complex faces a variety of serious and costly environmental problems. Second, during the past year, DOE has made some important changes to its organization that should help change its management focus from one that emphasizes materials production to one that more clearly focuses on environmental concerns. Third, because resolution of DOE's environmental problems will require considerable resources during a period of budgetary constraints, it is imperative that DOE have internal controls in place to ensure that resources are spent efficiently
Missing and Spurious Level Corrections for Nuclear Resonances
International Nuclear Information System (INIS)
Mitchell, G E; Agvaanluvsan, U; Pato, M P; Shriner, J F
2005-01-01
Neutron and proton resonances provide detailed level density information. However, due to experimental limitations, some levels are missed and some are assigned incorrect quantum numbers. The standard method to correct for missing levels uses the experimental widths and the Porter-Thomas distribution. Analysis of the spacing distribution provides an independent determination of the fraction of missing levels. We have derived a general expression for such an imperfect spacing distribution using the maximum entropy principle and applied it to a variety of nuclear resonance data. The problem of spurious levels has not been extensively addressed
Accurate light-time correction due to a gravitating mass
Energy Technology Data Exchange (ETDEWEB)
Ashby, Neil [Department of Physics, University of Colorado, Boulder, CO (United States); Bertotti, Bruno, E-mail: ashby@boulder.nist.go [Dipartimento di Fisica Nucleare e Teorica, Universita di Pavia (Italy)
2010-07-21
This technical paper of mathematical physics arose as an aftermath of the 2002 Cassini experiment (Bertotti et al 2003 Nature 425 374-6), in which the PPN parameter {gamma} was measured with an accuracy {sigma}{sub {gamma}} = 2.3 x 10{sup -5} and found consistent with the prediction {gamma} = 1 of general relativity. The Orbit Determination Program (ODP) of NASA's Jet Propulsion Laboratory, which was used in the data analysis, is based on an expression (8) for the gravitational delay {Delta}t that differs from the standard formula (2); this difference is of second order in powers of m-the gravitational radius of the Sun-but in Cassini's case it was much larger than the expected order of magnitude m{sup 2}/b, where b is the distance of the closest approach of the ray. Since the ODP does not take into account any other second-order terms, it is necessary, also in view of future more accurate experiments, to revisit the whole problem, to systematically evaluate higher order corrections and to determine which terms, and why, are larger than the expected value. We note that light propagation in a static spacetime is equivalent to a problem in ordinary geometrical optics; Fermat's action functional at its minimum is just the light-time between the two end points A and B. A new and powerful formulation is thus obtained. This method is closely connected with the much more general approach of Le Poncin-Lafitte et al (2004 Class. Quantum Grav. 21 4463-83), which is based on Synge's world function. Asymptotic power series are necessary to provide a safe and automatic way of selecting which terms to keep at each order. Higher order approximations to the required quantities, in particular the delay and the deflection, are easily obtained. We also show that in a close superior conjunction, when b is much smaller than the distances of A and B from the Sun, say of order R, the second-order correction has an enhanced part of order m{sup 2}R/b{sup 2}, which
Nuclear molecular structure in heavy mass systems
International Nuclear Information System (INIS)
Arctaedius, T.; Bargholtz, C.
1989-04-01
A study is made of nuclear molecular configurations involving one heavy mass partner. The stability of these configurations to mass flow and to fission is investigated as well as their population in fusion reactions. It is concluded that shell effects in combination with the effects of angular momentum may be important in stabilizing certain configurations. A possible relation of these configurations to the so called superdeformed states is pointed out. The spectrum of rotational and vibrational trasitions within molecular configurations is investigated. For sufficiently mass-asymmetric systems the engergies of vibrational transitions are comparable to the neutron separation energy. Gamma radiation from such transitions may then be observable above the background of statistical transitions. The gamma spectrum and the directional distribution of the radioation following fusion reactions with 12 C and 16 O are calculated. (authors)
Nuclear masses, deformations and shell effects
International Nuclear Information System (INIS)
Hirsch, Jorge G; Barbero, César A; Mariano, Alejandro E
2011-01-01
We show that the Liquid Drop Model is best suited to describe the masses of prolate deformed nuclei than of spherical nuclei. To this end three Liquid Drop Mass formulas are employed to describe nuclear masses of eight sets of nuclei with similar quadrupole deformations. It is shown that they are able to fit the measured masses of prolate deformed nuclei with an RMS smaller than 750 keV, while for the spherical nuclei the RMS is, in the three cases, larger than 2000 keV. The RMS of the best fit of the masses of semi-magic nuclei is also larger than 2000 keV. The parameters of the three models are studied, showing that the surface symmetry term is the one which varies the most from one group of nuclei to another. In one model, isospin dependent terms are also found to exhibit strong changes. The inclusion of shell effects allows for better fits, which continue to be better in the prolate deformed nuclei region.
Corrections to the box diagram amplitude due to kaon mass
International Nuclear Information System (INIS)
Datta, A.; Kumbhakar, D.
1985-08-01
The K 0 -anti-K 0 mixing amplitude is calculated without using the standard zero external momentum approximation. The resulting corrections are numerically significant for the real part of the amplitude. In the imaginary part of the amplitude the effects of similar corrections are less important. Implications for Δmsub(k) and epsilon are discussed. (author)
International Nuclear Information System (INIS)
Doherty, W.
2015-01-01
A nebulizer-centric instrument response function model of the plasma mass spectrometer was combined with a signal drift model, and the result was used to identify the causes of the non-spectroscopic determinate errors remaining in mass bias-corrected Pb isotope ratios (Tl as internal standard) measured using a multi-collector plasma mass spectrometer. Model calculations, confirmed by measurement, show that the detectable time-dependent errors are a result of the combined effect of signal drift and differences in the coordinates of the Pb and Tl response function maxima (horizontal offset effect). If there are no horizontal offsets, then the mass bias-corrected isotope ratios are approximately constant in time. In the absence of signal drift, the response surface curvature and horizontal offset effects are responsible for proportional errors in the mass bias-corrected isotope ratios. The proportional errors will be different for different analyte isotope ratios and different at every instrument operating point. Consequently, mass bias coefficients calculated using different isotope ratios are not necessarily equal. The error analysis based on the combined model provides strong justification for recommending a three step correction procedure (mass bias correction, drift correction and a proportional error correction, in that order) for isotope ratio measurements using a multi-collector plasma mass spectrometer
Impact of hadronic and nuclear corrections on global analysis of spin-dependent parton distributions
Energy Technology Data Exchange (ETDEWEB)
Jimenez-Delgado, Pedro [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Accardi, Alberto [Hampton University, Hampton, VA (United States); Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Melnitchouk, Wally [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
2014-02-01
We present the first results of a new global next-to-leading order analysis of spin-dependent parton distribution functions from the most recent world data on inclusive polarized deep-inelastic scattering, focusing in particular on the large-x and low-Q^2 regions. By directly fitting polarization asymmetries we eliminate biases introduced by using polarized structure function data extracted under nonuniform assumptions for the unpolarized structure functions. For analysis of the large-x data we implement nuclear smearing corrections for deuterium and 3He nuclei, and systematically include target mass and higher twist corrections to the g_1 and g_2 structure functions at low Q^2. We also explore the effects of Q^2 and W^2 cuts in the data sets, and the potential impact of future data on the behavior of the spin-dependent parton distributions at large x.
2013-07-31
... Environmental Review for Renewal of Nuclear Power Plant Operating Licenses; Correction AGENCY: Nuclear... nuclear power plant. Compliance with the provisions of the rule is required by June 20, 2014. This... environmental effect of renewing the operating license of a nuclear power plant. This document is necessary to...
Higgs mass dependence of electroweak radiative corrections and the triviality bound
Cortese, S.; Pallante, E.; Petronzio, R.
1993-01-01
We discuss how the existence of a triviality bound for the Higgs sector of the standard model does influence the dependence of radiative corrections upon the Higgs mass. The lowering of the Landau pole with increasing Higgs mass implies that the sensitivity to Higgs mass values beyond â‰ˆ 500 GeV is
Calculation of the collective mass-parameter including RPA corrections
International Nuclear Information System (INIS)
Pal, M.K.; Zawischa, D.; Speth, J.
1975-01-01
A derivation of the vibrational mass-parameter B is given which makes the consistency with RPA calculations explicit. The expected enhancement by the residual particle-hole and particle-particle interaction is demonstrated by solving the quasiparticle-RPA for deformed nuclei in the rare earth region. (orig.) [de
Impurity levels: corrections to the effective mass approximation
International Nuclear Information System (INIS)
Bentosela, F.
1977-07-01
Some rigorous results concerning the effective mass approximation used for the calculation of the impurity levels in semiconductors are presented. Each energy level is expressed as an asymptotic series in the inverse of the dielectric constant K, in the case where the impurity potential is 1/μ
Information filtering based on corrected redundancy-eliminating mass diffusion.
Zhu, Xuzhen; Yang, Yujie; Chen, Guilin; Medo, Matus; Tian, Hui; Cai, Shi-Min
2017-01-01
Methods used in information filtering and recommendation often rely on quantifying the similarity between objects or users. The used similarity metrics often suffer from similarity redundancies arising from correlations between objects' attributes. Based on an unweighted undirected object-user bipartite network, we propose a Corrected Redundancy-Eliminating similarity index (CRE) which is based on a spreading process on the network. Extensive experiments on three benchmark data sets-Movilens, Netflix and Amazon-show that when used in recommendation, the CRE yields significant improvements in terms of recommendation accuracy and diversity. A detailed analysis is presented to unveil the origins of the observed differences between the CRE and mainstream similarity indices.
DEFF Research Database (Denmark)
Pinkevych, Mykola; Cromer, Deborah; Tolstrup, Martin
2016-01-01
[This corrects the article DOI: 10.1371/journal.ppat.1005000.][This corrects the article DOI: 10.1371/journal.ppat.1005740.][This corrects the article DOI: 10.1371/journal.ppat.1005679.].......[This corrects the article DOI: 10.1371/journal.ppat.1005000.][This corrects the article DOI: 10.1371/journal.ppat.1005740.][This corrects the article DOI: 10.1371/journal.ppat.1005679.]....
Proton fragmentation functions considering finite-mass corrections
Energy Technology Data Exchange (ETDEWEB)
Moosavi Nejad, S.M. [Yazd University, Faculty of Physics, Yazd (Iran, Islamic Republic of); Institute for Research in Fundamental Sciences (IPM), School of Particles and Accelerators, Tehran (Iran, Islamic Republic of); Soleymaninia, M. [Payame Noor Universtiy, Department of Physics, Tehran (Iran, Islamic Republic of); Maktoubian, A. [Yazd University, Faculty of Physics, Yazd (Iran, Islamic Republic of)
2016-10-15
We present new sets of proton fragmentation functions (FFs) describing the production of protons from the gluon and each of the quarks, obtained by the NLO QCD fits to all relevant data sets of single-inclusive electron-positron annihilation. Specifically, we determine their uncertainties using the Gaussian method for error estimation. Our analysis is in good agreement with the e{sup +}e{sup -} annihilation data. We also include finite-mass effects of the proton in our calculations, a topic to which very little attention is paid in the literature. Proton mass effects turn out to be appreciable for gluon and light quark FFs. The inclusion of finite-mass effects tends to improve the overall description of the data by reducing the minimized χ{sup 2} values significantly. As an application, we apply the extracted FFs to make predictions for the scaled-energy distribution of protons inclusively produced in top quark decays at next-to-leading order, relying on the universality and scaling violations of FFs. (orig.)
Information filtering based on corrected redundancy-eliminating mass diffusion.
Directory of Open Access Journals (Sweden)
Xuzhen Zhu
Full Text Available Methods used in information filtering and recommendation often rely on quantifying the similarity between objects or users. The used similarity metrics often suffer from similarity redundancies arising from correlations between objects' attributes. Based on an unweighted undirected object-user bipartite network, we propose a Corrected Redundancy-Eliminating similarity index (CRE which is based on a spreading process on the network. Extensive experiments on three benchmark data sets-Movilens, Netflix and Amazon-show that when used in recommendation, the CRE yields significant improvements in terms of recommendation accuracy and diversity. A detailed analysis is presented to unveil the origins of the observed differences between the CRE and mainstream similarity indices.
Two-Loop Correction to the Higgs Boson Mass in the MRSSM
International Nuclear Information System (INIS)
Stöckinger, Dominik; Diessner, Philip; Kotlarski, Wojciech; Kalinowski, Jan
2015-01-01
We present the impact of two-loop corrections on the mass of the lightest Higgs boson in the minimal R-symmetric supersymmetric standard model (MRSSM). These shift the Higgs boson mass up by typically 5 GeV or more. The dominant corrections arise from strong interactions, and from the gluon and its N=2 superpartners, the sgluon and Dirac gluino, and these corrections further increase with large Dirac gluino mass. The two-loop contributions governed purely by Yukawa couplings and the MRSSM λ, Λ parameters are smaller. We also update our earlier analysis which showed that the MRSSM can accommodate the measured Higgs and W boson masses. Including the two-loop corrections increases the parameter space where the theory prediction agrees with the measurement.
Centre-of-mass corrections for the harmonic S+V potential model
International Nuclear Information System (INIS)
Palladino, B.E.; Ferreira, P.L.
1986-01-01
Center-of-Mass corrections to the mass spectrum and static properties of low-lying S-wave baryoins are discussed in the context of a relativistic, independent quark model, based on a Dirac equation, with equally mixed scalar and vector confining potential of harmomic type. A more stisfactory fitting of the parameters involved is obtained, as compared with previous treatments which CM corrections were neglected. (Author) [pt
Local quark-hadron duality of nucleon spin structure functions with target mass corrections
International Nuclear Information System (INIS)
Dong, Y.B. . E-mail dongyb@mail.ihep.ac.cn; Chen, D.Y.
2007-01-01
Target mass corrections to nucleon spin structure functions are analyzed. Our results show that the corrections are important to the structure functions in a large x region. Moreover, they play a remarkable role to the local quark-hadron duality of the nucleon spin structure functions in three individual inelastic resonance production regions
Hadronic corrections to electroweak observables from twisted mass lattice QCD
International Nuclear Information System (INIS)
Pientka, Grit
2015-01-01
For several benchmark quantities investigated to detect signs for new physics beyond the standard model of elementary particle physics, lattice QCD currently constitutes the only ab initio approach available at small momentum transfers for the computation of non-perturbative hadronic contributions. Among those observables are the lepton anomalous magnetic moments and the running of the electroweak coupling constants. We compute the leading QCD contribution to the muon anomalous magnetic moment by performing lattice QCD calculations on ensembles incorporating N f =2+1+1 dynamical twisted mass fermions. Considering active up, down, strange, and charm quarks, admits for the first time a direct comparison of the lattice data for the muon anomaly with phenomenological results because both the latter as well as the experimentally obtained values are sensitive to the complete first two generations of quarks at the current level of precision. Recently, it has been noted that improved measurements of the electron and tau anomalous magnetic moments might also provide ways of detecting new physics contributions. Therefore, we also compute their leading QCD contributions, which simultaneously serve as cross-checks of the value obtained for the muon. Additionally, we utilise the obtained data to compute the leading hadronic contribution to the running of the fine structure constant, which enters all perturbative QED calculations. Furthermore, we show that even for the weak mixing angle the leading QCD contribution can be computed from this data. In this way, we identify a new prime observable in the search for new physics whose hadronic contributions can be obtained from lattice QCD. With the results obtained in this thesis, we are able to exclude unsuitable phenomenologically necessary flavour separations and thus directly assist the presently more precise phenomenological determinations of this eminent quantity.
Center-of-mass corrections in the S+V potential model
International Nuclear Information System (INIS)
Palladino, B.E.
1987-02-01
Center-of-mass corrections to the mass spectrum and static properties of low-lying S-wave baryons and mesons are discussed in the context of a relativistic, independent quark model, based on a Dirac equation, with equally mixed scalar (S) and vector (V) confining potential. (author) [pt
$J/\\Psi$ mass shift in nuclear matter
Energy Technology Data Exchange (ETDEWEB)
Gastao Krein, Anthony Thomas, Kazuo Tsushima
2011-02-01
The $J/\\Psi$ mass shift in cold nuclear matter is computed using an effective Lagrangian approach. The mass shift is computed by evaluating $D$ and $D^*$ meson loop contributions to the $J/\\Psi$ self-energy employing medium-modified meson masses. The modification of the $D$ and $D^*$ masses in nuclear matter is obtained using the quark-meson coupling model. The loop integrals are regularized with dipole form factors and the sensitivity of the results to the values of form-factor cutoff masses is investigated. The $J/\\Psi$ mass shift arising from the modification of the $D$ and $D^*$ loops at normal nuclear matter density is found to range from $-16$~MeV to $-24$~MeV under a wide variation of values of the cutoff masses. Experimental perspectives for the formation of a bound state of $J/\\Psi$ to a nucleus are investigated.
Estimation of the self-attenuation correction factor for gamma rays emission from nuclear materials
International Nuclear Information System (INIS)
Badawy, A.; El-Gammal, W.A.
2001-01-01
This work presents an investigation of the self-attenuation of gamma-rays emission from nuclear materials (NMs) for measuring the U-235 enrichment, U-235 mass content and isotopic composition of NMs by non-destructive assay technique [NDA]. The measurements then would not need the use of suitable NM Standards which may not be available in many situations. The self-attenuation correction factor (F) may be estimated by the use of the linear attenuation factor of the assayed sample, the geometrical configuration of the assay set-up and the position of the assayed sample relative to the detector. A developed mathematical analysis makes use of specific parameters which affect the estimation of the self-attenuation of the source-detector system which emits passive gamma-rays at certain prominent signatures
The modified version of the centre-of-mass correction to the bag model
International Nuclear Information System (INIS)
Bartelski, J.; Tatur, S.
1986-01-01
We propose the improvement of the recently considered version of the centre-of-mass correction to the bag model. We identify a nucleon bag with physical nucleon confined in an external fictitious spherical well potential with an additional external fictitious pressure characterized by the parameter b. The introduction of such a pressure restores the conservation of the canonical energy-momentum tensor, which was lost in the former model. We propose several methods to determine the numerical value of b. We calculate the Roper resonance mass as well as static electroweak parameters of a nucleon with centre-of-mass corrections taken into account. 7 refs., 1 tab. (author)
Current s - quark mass corrections to the form factors of D - meson semileptonic decays
International Nuclear Information System (INIS)
Hussain, F.; Ivanov, A.N.; Troitskaya, N.I.
1994-11-01
The infinite mass effective theory, when a heavy quark mass tends to infinity, and Chiral perturbation theory at the quark level, based on the extended Nambu - Jona - Lasinio model with linear realization of chiral U(3) x U(3) symmetry, are applied to the calculations of current s - quark mass corrections to the form factors of the D → K-bar e + ν e and D → K-bar * e + ν e decays. These corrections turn out to be quite significant, of the order of 7 - 20%. The theoretical results are compared with experimental data. (author). 17 refs
Impact of Precision Mass Measurements on Nuclear Physics and Astrophysics
Kreim, Susanne; Dilling, Jens; Litvinov, Yuri A
2013-01-01
Among all nuclear ground-state properties, atomic masses are highly specific for each particular combination of neutron and proton number, N and Z, respectively. The data obtained through mass measurements provide details of the nuclear interaction and thus apply to a variety of physics topics. Some of the most crucial questions to be addressed by mass spectrometry of unstable radionuclides are, on the one hand, nuclear forces and structure, describing phenomena such as the so-called neutron-halos or the evolution of magic numbers when moving towards the borders of nuclear existence. On the other hand, the understanding of the processes of element formation in the Universe poses a challenge and requires an accurate knowledge of nuclear astrophysics. Here, precision atomic mass values of a large number of exotic nuclei participating in nucleosynthesis processes are among the key input data in large-scale reaction network calculations.
Refitting density dependent relativistic model parameters including Center-of-Mass corrections
International Nuclear Information System (INIS)
Avancini, Sidney S.; Marinelli, Jose R.; Carlson, Brett Vern
2011-01-01
Full text: Relativistic mean field models have become a standard approach for precise nuclear structure calculations. After the seminal work of Serot and Walecka, which introduced a model Lagrangian density where the nucleons interact through the exchange of scalar and vector mesons, several models were obtained through its generalization, including other meson degrees of freedom, non-linear meson interactions, meson-meson interactions, etc. More recently density dependent coupling constants were incorporated into the Walecka-like models, which are then extensively used. In particular, for these models a connection with the density functional theory can be established. Due to the inherent difficulties presented by field theoretical models, only the mean field approximation is used for the solution of these models. In order to calculate finite nuclei properties in the mean field approximation, a reference set has to be fixed and therefore the translational symmetry is violated. It is well known that in such case spurious effects due to the center-of-mass (COM) motion are present, which are more pronounced for light nuclei. In a previous work we have proposed a technique based on the Pierls-Yoccoz projection operator applied to the mean-field relativistic solution, in order to project out spurious COM contributions. In this work we obtain a new fitting for the density dependent parameters of a density dependent hadronic model, taking into account the COM corrections. Our fitting is obtained taking into account the charge radii and binding energies for He 4 , O 16 , Ca 40 , Ca 48 , Ni 56 , Ni 68 , Sn 100 , Sn 132 and Pb 208 . We show that the nuclear observables calculated using our fit are of a quality comparable to others that can be found in the literature, with the advantage that now a translational invariant many-body wave function is at our disposal. (author)
Proposal for the determination of nuclear masses by high-precision spectroscopy of Rydberg states
International Nuclear Information System (INIS)
Wundt, B J; Jentschura, U D
2010-01-01
The theoretical treatment of Rydberg states in one-electron ions is facilitated by the virtual absence of the nuclear-size correction, and fundamental constants like the Rydberg constant may be in the reach of planned high-precision spectroscopic experiments. The dominant nuclear effect that shifts transition energies among Rydberg states therefore is due to the nuclear mass. As a consequence, spectroscopic measurements of Rydberg transitions can be used in order to precisely deduce nuclear masses. A possible application of this approach to hydrogen and deuterium, and hydrogen-like lithium and carbon is explored in detail. In order to complete the analysis, numerical and analytic calculations of the quantum electrodynamic self-energy remainder function for states with principal quantum number n = 5, ..., 8 and with angular momentum l = n - 1 and l = n - 2 are described (j = l +- 1/2).
Proposal for the determination of nuclear masses by high-precision spectroscopy of Rydberg states
Energy Technology Data Exchange (ETDEWEB)
Wundt, B J; Jentschura, U D [Department of Physics, Missouri University of Science and Technology, Rolla, MO 65409-0640 (United States)
2010-06-14
The theoretical treatment of Rydberg states in one-electron ions is facilitated by the virtual absence of the nuclear-size correction, and fundamental constants like the Rydberg constant may be in the reach of planned high-precision spectroscopic experiments. The dominant nuclear effect that shifts transition energies among Rydberg states therefore is due to the nuclear mass. As a consequence, spectroscopic measurements of Rydberg transitions can be used in order to precisely deduce nuclear masses. A possible application of this approach to hydrogen and deuterium, and hydrogen-like lithium and carbon is explored in detail. In order to complete the analysis, numerical and analytic calculations of the quantum electrodynamic self-energy remainder function for states with principal quantum number n = 5, ..., 8 and with angular momentum l = n - 1 and l = n - 2 are described (j = l {+-} 1/2).
Burnup determination of mass spectrometry for nuclear fuels
International Nuclear Information System (INIS)
Zhang Chunhua.
1987-01-01
The various methods currently being used in burnup determination of nuclear fuels are studied and reviewed. The mass spectrometry method of destructive testing is discussed emphatically. The burnup determination of mass spectrometry includes heavy isotopic abundance ratio method and isotope dilution mass spectrometry used as burnup indicator for the fission products. The former is applied to high burnup level, but the later to various burnup level. According to experiences, some problems which should be noticed in burnup determination of mass spectrometry are presented
The ρ - ω mass difference in a relativistic potential model with pion corrections
International Nuclear Information System (INIS)
Palladino, B.E.; Ferreira, P.L.
1988-01-01
The problem of the ρ - ω mass difference is studied in the framework of the relativistic, harmonic, S+V independent quark model implemented by center-of-mass, one-gluon exchange and plon-cloud corrections stemming from the requirement of chiral symmetry in the (u,d) SU(2) flavour sector of the model. The plonic self-energy corrections with different intermediate energy states are instrumental of the analysis of the problem, which requires and appropriate parametrization of the mesonic sector different from that previously used to calculate the mass spectrum of the S-wave baryons. The right ρ - ω mass splitting is found, together with a satisfactory value for the mass of the pion, calculated as a bound-state of a quark-antiquark pair. An analogous discussion based on the cloudy-bag model is also presented. (author) [pt
Operating experience and corrective action program at Ontario Hydro Nuclear
International Nuclear Information System (INIS)
Collingwood, Barry; Turner, David
1998-01-01
This is a slide-based talk given at the COG/IAEA: 5. Technical Committee Meeting on 'Exchange of operating experience of pressurized heavy water reactors'. In the introduction there are presented the operating experience (OPEX) program of OHN, and the OPEX Program Mission, ensuring that the right information gets to the right staff at the right time. The OPEX Processes are analysed. These are: - Internal Corrective Action; - Inter-site Lesson Transfer; - External Lesson Transfer; - External Posting of OHN Events; - Internalizing Operating Experience. Steps in solving the Corrective Action Program are described: - Identify the Problem; - Notify Immediate Supervision/Manager; - Evaluate the Problem; - Correct the Problem; Monitor/Report Status. The Internal Corrective Action is then presented as a flowchart. The internalizing operating experience is presented under three aspects: - Communication; - Interface; - Training. The following items are discussed, respectively: peer meetings, department/section meetings, safety meetings, e-mail folders, newsletters and bulletin boards; work planning, pre-job briefings, supervisors' briefing cards; classroom initial and refresher (case studies), simulator, management courses. A diagram is presented showing the flow and treatment of information within OHN, centered on the weekly screening meetings. Finally, the corrective action processes are depicted in a flowchart and analysed in details
Energy Technology Data Exchange (ETDEWEB)
Bilbao, Aivett; Gibbons, Bryson C.; Slysz, Gordon W.; Crowell, Kevin L.; Monroe, Matthew E.; Ibrahim, Yehia M.; Smith, Richard D.; Payne, Samuel H.; Baker, Erin S.
2018-04-01
The mass accuracy and peak intensity of ions detected by mass spectrometry (MS) measurements are essential to facilitate compound identification and quantitation. However, high concentration species can easily cause problems if their ion intensities reach beyond the limits of the detection system, leading to distorted and non-ideal detector response (e.g. saturation), and largely precluding the calculation of accurate m/z and intensity values. Here we present an open source computational method to correct peaks above a defined intensity (saturated) threshold determined by the MS instrumentation such as the analog-to-digital converters or time-to-digital converters used in conjunction with time-of-flight MS. In this method, the isotopic envelope for each observed ion above the saturation threshold is compared to its expected theoretical isotopic distribution. The most intense isotopic peak for which saturation does not occur is then utilized to re-calculate the precursor m/z and correct the intensity, resulting in both higher mass accuracy and greater dynamic range. The benefits of this approach were evaluated with proteomic and lipidomic datasets of varying complexities. After correcting the high concentration species, reduced mass errors and enhanced dynamic range were observed for both simple and complex omic samples. Specifically, the mass error dropped by more than 50% in most cases with highly saturated species and dynamic range increased by 1-2 orders of magnitude for peptides in a blood serum sample.
International Nuclear Information System (INIS)
D'Alesio, U.; Leader, E.; Murgia, F.
2010-01-01
We show that respecting the underlying Lorentz structure in the parton model has very strong consequences. Failure to insist on the correct Lorentz covariance is responsible for the existence of contradictory results in the literature for the polarized structure function g 2 (x), whereas with the correct imposition we are able to derive the Wandzura-Wilczek relation for g 2 (x) and the target-mass corrections for polarized deep inelastic scattering without recourse to the operator product expansion. We comment briefly on the problem of threshold behavior in the presence of target-mass corrections. Careful attention to the Lorentz structure has also profound implications for the structure of the transverse momentum dependent parton densities often used in parton model treatments of hadron production, allowing the k T dependence to be derived explicitly. It also leads to stronger positivity and Soffer-type bounds than usually utilized for the collinear densities.
Analytical model for relativistic corrections to the nuclear magnetic shielding constant in atoms
Energy Technology Data Exchange (ETDEWEB)
Romero, Rodolfo H. [Facultad de Ciencias Exactas, Universidad Nacional del Nordeste, Avenida Libertad 5500 (3400), Corrientes (Argentina)]. E-mail: rhromero@exa.unne.edu.ar; Gomez, Sergio S. [Facultad de Ciencias Exactas, Universidad Nacional del Nordeste, Avenida Libertad 5500 (3400), Corrientes (Argentina)
2006-04-24
We present a simple analytical model for calculating and rationalizing the main relativistic corrections to the nuclear magnetic shielding constant in atoms. It provides good estimates for those corrections and their trends, in reasonable agreement with accurate four-component calculations and perturbation methods. The origin of the effects in deep core atomic orbitals is manifestly shown.
Analytical model for relativistic corrections to the nuclear magnetic shielding constant in atoms
International Nuclear Information System (INIS)
Romero, Rodolfo H.; Gomez, Sergio S.
2006-01-01
We present a simple analytical model for calculating and rationalizing the main relativistic corrections to the nuclear magnetic shielding constant in atoms. It provides good estimates for those corrections and their trends, in reasonable agreement with accurate four-component calculations and perturbation methods. The origin of the effects in deep core atomic orbitals is manifestly shown
The Gogny-Hartree-Fock-Bogoliubov nuclear-mass model
Energy Technology Data Exchange (ETDEWEB)
Goriely, S. [Universite Libre de Bruxelles, Institut d' Astronomie et d' Astrophysique, CP-226, Brussels (Belgium); Hilaire, S.; Girod, M.; Peru, S. [CEA, DAM, DIF, Arpajon (France)
2016-07-15
We present the Gogny-Hartree-Fock-Bogoliubov model which reproduces nuclear masses with an accuracy comparable with the best mass formulas. In contrast to the Skyrme-HFB nuclear-mass models, an explicit and self-consistent account of all the quadrupole correlation energies is included within the 5D collective Hamiltonian approach. The final rms deviation with respect to the 2353 measured masses is 789 keV in the 2012 atomic mass evaluation. In addition, the D1M Gogny force is shown to predict nuclear and neutron matter properties in agreement with microscopic calculations based on realistic two- and three-body forces. The D1M properties and its predictions of various observables are compared with those of D1S and D1N. (orig.)
Corrective maintenance support system for nuclear power plants
International Nuclear Information System (INIS)
Kakiuchi, Tetsuo
1996-01-01
With increase of share of nuclear power generation in electric power supply in Japan, requirement for further safe operation and improvement of economics for the nuclear power plants is promoting. The pressed water type (PWR) nuclear power plant in operation in Japan reaches to 22 sets, application rate of the instruments is 74% as mean value for 7 years since 1989 and in high level, which is due to a result of preventive maintenance in ordinary and periodical inspections. The present state of maintenance at the nuclear power plant is mainly preventive maintenance, which is mainly conducted in a shape of time planning maintenance but partially in a shape of state monitoring maintenance for partial rotating appliances. Concretely speaking, the periodical inspection was planned on a base of daily inspection and a long term program on maintenance, and executed on a base of feedback function to think of the long term program again by evaluating the periodical inspection results. Here were introduced on the monitoring diagnosis and periodical inspection regionalization equipment, fatigue monitoring system, automatic supersonic wave damage inspection equipment for reactor, steam evaporator heat conductive tube inspection equipment, automatic testing equipment for measuring controller, air working valve property testing equipment, as maintaining support system in the PW generation plant. (G.K.)
Optimization and Experimentation of Dual-Mass MEMS Gyroscope Quadrature Error Correction Methods.
Cao, Huiliang; Li, Hongsheng; Kou, Zhiwei; Shi, Yunbo; Tang, Jun; Ma, Zongmin; Shen, Chong; Liu, Jun
2016-01-07
This paper focuses on an optimal quadrature error correction method for the dual-mass MEMS gyroscope, in order to reduce the long term bias drift. It is known that the coupling stiffness and demodulation error are important elements causing bias drift. The coupling stiffness in dual-mass structures is analyzed. The experiment proves that the left and right masses' quadrature errors are different, and the quadrature correction system should be arranged independently. The process leading to quadrature error is proposed, and the Charge Injecting Correction (CIC), Quadrature Force Correction (QFC) and Coupling Stiffness Correction (CSC) methods are introduced. The correction objects of these three methods are the quadrature error signal, force and the coupling stiffness, respectively. The three methods are investigated through control theory analysis, model simulation and circuit experiments, and the results support the theoretical analysis. The bias stability results based on CIC, QFC and CSC are 48 °/h, 9.9 °/h and 3.7 °/h, respectively, and this value is 38 °/h before quadrature error correction. The CSC method is proved to be the better method for quadrature correction, and it improves the Angle Random Walking (ARW) value, increasing it from 0.66 °/√h to 0.21 °/√h. The CSC system general test results show that it works well across the full temperature range, and the bias stabilities of the six groups' output data are 3.8 °/h, 3.6 °/h, 3.4 °/h, 3.1 °/h, 3.0 °/h and 4.2 °/h, respectively, which proves the system has excellent repeatability.
Adaptive topographic mass correction for satellite gravity and gravity gradient data
Holzrichter, Nils; Szwillus, Wolfgang; Götze, Hans-Jürgen
2014-05-01
Subsurface modelling with gravity data includes a reliable topographic mass correction. Since decades, this mandatory step is a standard procedure. However, originally methods were developed for local terrestrial surveys. Therefore, these methods often include defaults like a limited correction area of 167 km around an observation point, resampling topography depending on the distance to the station or disregard the curvature of the earth. New satellite gravity data (e.g. GOCE) can be used for large scale lithospheric modelling with gravity data. The investigation areas can include thousands of kilometres. In addition, measurements are located in the flight height of the satellite (e.g. ~250 km for GOCE). The standard definition of the correction area and the specific grid spacing around an observation point was not developed for stations located in these heights and areas of these dimensions. This asks for a revaluation of the defaults used for topographic correction. We developed an algorithm which resamples the topography based on an adaptive approach. Instead of resampling topography depending on the distance to the station, the grids will be resampled depending on its influence at the station. Therefore, the only value the user has to define is the desired accuracy of the topographic correction. It is not necessary to define the grid spacing and a limited correction area. Furthermore, the algorithm calculates the topographic mass response with a spherical shaped polyhedral body. We show examples for local and global gravity datasets and compare the results of the topographic mass correction to existing approaches. We provide suggestions how satellite gravity and gradient data should be corrected.
Target mass corrections to electroweak structure functions and perturbative neutrino cross sections
International Nuclear Information System (INIS)
Kretzer, S.; Reno, M.H.
2004-01-01
We provide a complete and consistent framework to include subasymptotic perturbative as well as mass corrections to the leading twist (τ=2) evaluation of charged and neutral current weak structure functions and the perturbative neutrino cross sections. We reexamine previous calculations in a modern language and fill in the gaps that we find missing for a complete and ready-to-use 'NLO ξ-scaling' formulary. In particular, as a new result we formulate the mixing of the partonic and hadronic structure function tensor basis in the operator approach to deep inelastic scattering. As an underlying framework we follow the operator product expansion in the manner of Georgi and Politzer that allows the inclusion of target mass corrections at arbitrary order in QCD and we provide explicit analytical and numerical results at NLO. We compare this approach with a simpler collinear parton model approach to ξ scaling. Along with target mass corrections we include heavy quark mass effects as a calculable leading twist power suppressed correction. The complete corrections have been implemented into a Monte Carlo integration program to evaluate structure functions and/or integrated cross sections. As applications, we compare the operator approach with the collinear approximation numerically and we investigate the NLO and mass corrections to observables that are related to the extraction of the weak mixing angle from a Paschos-Wolfenstein-like relation in neutrino-iron scattering. We expect that the interpretation of neutrino scattering events in terms of oscillation physics and electroweak precision physics will benefit from our results
Oblique corrections in a model with neutrino masses and strong C P resolution
International Nuclear Information System (INIS)
Natale, A.A.; Rodrigues da Silva, P.S.
1994-01-01
Our intention in this work is to verify what is the order of the limits we obtain on the light neutrino masses, through the calculation and comparison of the oblique corrections with the experimental data. The calculation will be performed for a specific model, although we expect it to be sufficiently general to give one idea of the limits that can be obtained on neutrino masses in this class of models. (author)
Applications of accelerator mass spectrometry to nuclear physics and astrophysics
International Nuclear Information System (INIS)
Guo Zhiyu; Zhang Chuan
2002-01-01
As an ultra high sensitive analyzing method, accelerator mass spectrometry is playing an important role in the studies of nuclear physics and astrophysics. The accelerator mass spectrometry (AMS) applications in searching for violation of Pauli exclusion principle and study on supernovae are discussed as examples
Mass media and nuclear energy - IAEA's role
International Nuclear Information System (INIS)
Kyd, D.R.
1993-11-01
The presentation covers the following areas: the wide spectrum of media outlets that the IAEA seeks to serve and their differing needs; the resources available to the IAEA for that purpose; the way in which IAEA endeavours to disseminate authoritative, reliable nuclear-related information to media; the exceptional role the IAEA may be called on to play in emergency situations
Mass Producing Targets for Nuclear Fusion
Wang, T. G.; Elleman, D. D.; Kendall, J. M.
1983-01-01
Metal-encapsulating technique advances prospects of controlling nuclear fusion. Prefilled fusion targets form at nozzle as molten metal such as tin flows through outer channel and pressurized deuterium/tritium gas flows through inner channel. Molten metal completely encloses gas charge as it drops off nozzle.
Giusti, D.; Lubicz, V.; Tarantino, C.; Martinelli, G.; Sanfilippo, F.; Simula, S.; Tantalo, N.; RM123 Collaboration
2017-06-01
We present a lattice computation of the isospin-breaking corrections to pseudoscalar meson masses using the gauge configurations produced by the European Twisted Mass Collaboration with Nf=2 +1 +1 dynamical quarks at three values of the lattice spacing (a ≃0.062 , 0.082, and 0.089 fm) with pion masses in the range Mπ≃210 - 450 MeV . The strange and charm quark masses are tuned at their physical values. We adopt the RM123 method based on the combined expansion of the path integral in powers of the d - and u -quark mass difference (m^d-m^u) and of the electromagnetic coupling αe m. Within the quenched QED approximation, which neglects the effects of the sea-quark charges, and after the extrapolations to the physical pion mass and to the continuum and infinite volume limits, we provide results for the pion, kaon, and (for the first time) charmed-meson mass splittings, for the prescription-dependent parameters ɛπ0, ɛγ(M S ¯ ,2 GeV ) , ɛK0(M S ¯ ,2 GeV ) , related to the violations of the Dashen's theorem, and for the light quark mass difference (m^ d-m^ u)(M S ¯ ,2 GeV ) .
International Nuclear Information System (INIS)
Sutterley, Tyler C; Velicogna, Isabella; Csatho, Beata; Rezvan-Behbahani, Soroush; Babonis, Greg; Van den Broeke, Michiel
2014-01-01
Glacial isostatic adjustment (GIA) represents a source of uncertainty for ice sheet mass balance estimates from the Gravity Recovery and Climate Experiment (GRACE) time-variable gravity measurements. We evaluate Greenland GIA corrections from Simpson et al (2009 Quat. Sci. Rev. 28 1631–57), A et al (2013 Geophys. J. Int. 192 557–72) and Wu et al (2010 Nature Geosci. 3 642–6) by comparing the spatial patterns of GRACE-derived ice mass trends calculated using the three corrections with volume changes from ICESat (Ice, Cloud, and land Elevation Satellite) and OIB (Operation IceBridge) altimetry missions, and surface mass balance products from the Regional Atmospheric Climate Model (RACMO). During the period September 2003–August 2011, GRACE ice mass changes obtained using the Simpson et al (2009 Quat. Sci. Rev. 28 1631–57) and A et al (2013 Geophys. J. Int. 192 557–72) GIA corrections yield similar spatial patterns and amplitudes, and are consistent with altimetry observations and surface mass balance data. The two GRACE estimates agree within 2% on average over the entire ice sheet, and better than 15% in four subdivisions of Greenland. The third GRACE estimate corrected using the (Wu et al 2010 Nature Geosci. 3 642–6)) GIA shows similar spatial patterns, but produces an average ice mass loss for the entire ice sheet that is 64 − 67 Gt yr −1 smaller. In the Northeast the recovered ice mass change is 46–49 Gt yr −1 (245–270%) more positive than that deduced from the other two corrections. By comparing the spatial and temporal variability of the GRACE estimates with trends of volume changes from altimetry and surface mass balance from RACMO, we show that the Wu et al (2010 Nature Geosci. 3 642–6) correction leads to a large mass increase in the Northeast that is inconsistent with independent observations. (paper)
Nuclear security. Improving correction of security deficiencies at DOE's weapons facilities
International Nuclear Information System (INIS)
Wells, James E.; Cannon, Doris E.; Fenzel, William F.; Lightner, Kenneth E. Jr.; Curtis, Lois J.; DuBois, Julia A.; Brown, Gail W.; Trujillo, Charles S.; Tumler, Pamela K.
1992-11-01
The US nuclear weapons research, development, and production are conducted at 10 DOE nuclear weapons facilities by contractors under the guidance and oversight of 9 DOE field offices. Because these facilities house special nuclear materials used in making nuclear weapons and nuclear weapons components, DOE administers a security program to protect (1) against theft, sabotage, espionage, terrorism, or other risks to national security and (2) the safety and health of DOE employees and the public. DOE spends almost $1 billion a year on this security program. DOE administers the security program through periodic inspections that evaluate and monitor the effectiveness of facilities' safeguards and security. Security inspections identify deficiencies, instances of noncompliance with safeguards and security requirements or poor performance of the systems being evaluated, that must be corrected to maintain adequate security. The contractors and DOE share responsibility for correcting deficiencies. Contractors, in correcting deficiencies, must comply with several DOE orders. The contractors' performances were not adequate in conducting four of the eight procedures considered necessary in meeting DOE's deficiency correction requirements. For 19 of the 20 deficiency cases we reviewed, contractors could not demonstrate that they had conducted three critical deficiency analyses (root cause, risk assessment, and cost-benefit) required by DOE. Additionally, the contractors did not always adequately verify that corrective actions taken were appropriate, effective, and complete. The contractors performed the remaining four procedures (reviewing deficiencies for duplication, entering deficiencies into a data base, tracking the status of deficiencies, and preparing and implementing a corrective action plan) adequately in all 20 cases. DOE's oversight of the corrective action process could be improved in three areas. The computerized systems used to track the status of security
A simple method for improving predictions of nuclear masses
International Nuclear Information System (INIS)
Yamada, Masami; Tsuchiya, Susumu; Tachibana, Takahiro
1991-01-01
The formula for atomic masses which exactly conforms to all nuclides does not exist in reality and cannot be anticipated for the time being hereafter. At present the masses of many nuclides are known experimentally with good accuracy, but the values of whichever mass formulas are more or less different from those experimental values except small number of accidental coincidence. Under such situation, for forecasting the mass of an unknown nuclide, how is it cleverly done ? Generally speaking, to take the value itself of a mass formula seems not the best means. It may be better to take the difference of the values of a mass formula and experiment for the nuclide close to that to be forecast in consideration and to correct the forecast value of the mass formula. In this report, the simple method for this correction is proposed. The formula which connects between two extreme cases, the difference between a true mass and the value of a mass formula is the sum of proton part and neutron part, and the difference distributes randomly around zero, was proposed. The procedure for its concrete application is explained. This method can be applied to other physical quantities than mass, for example the half life of beta decay. (K.I.)
Hartree-Fock calculations of nuclear masses
International Nuclear Information System (INIS)
Quentin, P.
1976-01-01
Hartree-Fock calculations pertaining to the determination of nuclear binding energies throughout the whole chart of nuclides are reviewed. Such an approach is compared with other methods. Main techniques in use are shortly presented. Advantages and drawbacks of these calculations are also discussed with a special emphasis on the extrapolation towards nuclei far from the stability valley. Finally, a discussion of some selected results from light to superheavy nuclei, is given [fr
Experimental Guidance of ISB Corrections via Direct Nuclear Reactions
Leach, K. G.; Garrett, P. E.; Ball, G. C.; Bangay, J. C.; Bianco, L.; Demand, G. A.; Faestermann, T.; Finlay, P.; Green, K. L.; Hertenberger, R.; Kriicken, R.; Phillips, A. A.; Rand, E. T.; Sumithrarachchi, C. S.; Svensson, C. E.; Towner, I. S.; Triambak, S.; Wirth, H.-F.; Wong, J.
2011-09-01
The most recent isospin-symmetry-breaking corrections, δc, of Towner and Hardy for superallowed Fermi β-decay transitions, have included the opening of specific core orbitals. This change has resulted in significant deviations in some of the δc factors from their previous calculations, and an improved agreement of the individual corrected Script Ft values with the overall world average of the 13 most precise cases. While this is consistent with the conserved-vector-current (CVC) hypothesis of the Standard Model, these new calculations must be thoroughly tested, and guidance must be given for the improvement of calculations for the upper-pf shell nuclei. Using the (d,t) reaction mechanism to probe the single neutron wavefunction overlap, information regarding the relevant shell-model configurations needed in the calculation can be determined. An experiment was therefore performed with a 22 MeV polarized deuterium beam from the MP tandem Van de Graaff accelerator in Munich, Germany. Using the Q3D magnetic spectrograph, and a cathode-strip focal-plane detector, outgoing tritons were analyzed at 9 angles between 10° and 60°, up to an excitation energy of 4.8 MeV. This proceeding reports the motivational and experimental details for the 64Zn(d,t)63Zn transfer work presented.
Optimization and Experimentation of Dual-Mass MEMS Gyroscope Quadrature Error Correction Methods
Directory of Open Access Journals (Sweden)
Huiliang Cao
2016-01-01
Full Text Available This paper focuses on an optimal quadrature error correction method for the dual-mass MEMS gyroscope, in order to reduce the long term bias drift. It is known that the coupling stiffness and demodulation error are important elements causing bias drift. The coupling stiffness in dual-mass structures is analyzed. The experiment proves that the left and right masses’ quadrature errors are different, and the quadrature correction system should be arranged independently. The process leading to quadrature error is proposed, and the Charge Injecting Correction (CIC, Quadrature Force Correction (QFC and Coupling Stiffness Correction (CSC methods are introduced. The correction objects of these three methods are the quadrature error signal, force and the coupling stiffness, respectively. The three methods are investigated through control theory analysis, model simulation and circuit experiments, and the results support the theoretical analysis. The bias stability results based on CIC, QFC and CSC are 48 °/h, 9.9 °/h and 3.7 °/h, respectively, and this value is 38 °/h before quadrature error correction. The CSC method is proved to be the better method for quadrature correction, and it improves the Angle Random Walking (ARW value, increasing it from 0.66 °/√h to 0.21 °/√h. The CSC system general test results show that it works well across the full temperature range, and the bias stabilities of the six groups’ output data are 3.8 °/h, 3.6 °/h, 3.4 °/h, 3.1 °/h, 3.0 °/h and 4.2 °/h, respectively, which proves the system has excellent repeatability.
Optimization and Experimentation of Dual-Mass MEMS Gyroscope Quadrature Error Correction Methods
Cao, Huiliang; Li, Hongsheng; Kou, Zhiwei; Shi, Yunbo; Tang, Jun; Ma, Zongmin; Shen, Chong; Liu, Jun
2016-01-01
This paper focuses on an optimal quadrature error correction method for the dual-mass MEMS gyroscope, in order to reduce the long term bias drift. It is known that the coupling stiffness and demodulation error are important elements causing bias drift. The coupling stiffness in dual-mass structures is analyzed. The experiment proves that the left and right masses’ quadrature errors are different, and the quadrature correction system should be arranged independently. The process leading to quadrature error is proposed, and the Charge Injecting Correction (CIC), Quadrature Force Correction (QFC) and Coupling Stiffness Correction (CSC) methods are introduced. The correction objects of these three methods are the quadrature error signal, force and the coupling stiffness, respectively. The three methods are investigated through control theory analysis, model simulation and circuit experiments, and the results support the theoretical analysis. The bias stability results based on CIC, QFC and CSC are 48 °/h, 9.9 °/h and 3.7 °/h, respectively, and this value is 38 °/h before quadrature error correction. The CSC method is proved to be the better method for quadrature correction, and it improves the Angle Random Walking (ARW) value, increasing it from 0.66 °/√h to 0.21 °/√h. The CSC system general test results show that it works well across the full temperature range, and the bias stabilities of the six groups’ output data are 3.8 °/h, 3.6 °/h, 3.4 °/h, 3.1 °/h, 3.0 °/h and 4.2 °/h, respectively, which proves the system has excellent repeatability. PMID:26751455
The fuzzy bag and baryonic properties with center of mass and recoil corrections
International Nuclear Information System (INIS)
Pilotto, F.
2003-01-01
The fuzzy bag is a hadronic model which has features both of the bag model (energy-momentum conservation, QCD vacuum energy) and of relativistic potential models (confinement achieved through a potential). It is also a chiral model, with the unique property that the pion field is suppressed in the interior of the bag by means of a scalar potential, and yet chiral symmetry is preserved. This scalar potential allows one to control how far the pion field can penetrate in the interior of the bag. We calculate the masses of the fundamental baryon octet taking into account the center of mass, one-gluon exchange and one-pion exchange corrections. We also calculate the nucleon axial charge, charge radii and magnetic moments including center of mass and recoil corrections. The agreement with experiment is excellent, and the results indicate that the pion field is suppressed only very close to the center of the bag. (orig.)
Application of accelerator mass spectrometry in nuclear science
International Nuclear Information System (INIS)
Wang Xiaobo; Hu Jinjun; Wang Huijuan; Guan Yongjing; Wang Wei
2013-01-01
Accelerator mass spectrometry (AMS) is a promising method to provide extreme sensitivity measurements of the production yields of long-lived radioisotopes, which cannot be detected by other methods. AMS technique plays an important role in the research of nuclear physics, as well as the application field of AMS covered nuclear science and technology, life science, earth science, environmental science, archaeology etc. The newest AMS field is that of actinide, particularly U and Pu, isotopic assay with expanding applications in nuclear safeguards and monitoring, and as a modern bomb-fallout tracer for atmospheric transport and surface sediment movement. This paper reviews the applications of AMS in the research of nuclear energy and nuclear security including the research of half life of radionuclides, cross section of nuclear reaction. (authors)
Wagner, Craig D; Hall, John T; White, Wendy L; Miller, Luke A D; Williams, Jon D
2007-02-01
Characterization of recombinant protein purification fractions and final products by liquid chromatography-mass spectrometry (LC/MS) are requested more frequently each year. A protein open-access (OA) LC/MS system was developed in our laboratory to meet this demand. This paper compares the system that we originally implemented in our facilities in 2003 to the one now in use, and discusses, in more detail, recent enhancements that have improved its robustness, reliability, and data reporting capabilities. The system utilizes instruments equipped with reversed-phase chromatography and an orthogonal accelerated time-of-flight mass spectrometer fitted with an electrospray source. Sample analysis requests are accomplished using a simple form on a web-enabled laboratory information management system (LIMS). This distributed form is accessible from any intranet-connected company desktop computer. Automated data acquisition and processing are performed using a combination of in-house (OA-Self Service, OA-Monitor, and OA-Analysis Engine) and vendor-supplied programs (AutoLynx, and OpenLynx) located on acquisition computers and off-line processing workstations. Analysis results are then reported via the same web-based LIMS. Also presented are solutions to problems not addressed on commercially available, small-molecule OA-LC/MS systems. These include automated transforming of mass-to-charge (m/z) spectra to mass spectra and automated data interpretation that considers minor variants to the protein sequence-such as common post-translational modifications (PTMs). Currently, our protein OA-LC/MS platform runs on five LC/MS instruments located in three separate GlaxoSmithKline R&D sites in the US and UK. To date, more than 8000 protein OA-LC/MS samples have been analyzed. With these user friendly and highly automated OA systems in place, mass spectrometry plays a key role in assessing the quality of recombinant proteins, either produced at our facilities or bought from external
Non extensive corrections to stellar nuclear reactions rate
Energy Technology Data Exchange (ETDEWEB)
Assuncao, M. [Universidade Federal de Sao Paulo (DCET/UNIFESP), Diadema, SP (Brazil). Dept. de Ciencias Exatas e da Terra; Silveira, F.E.M. [Universidade Federal do ABC, Santo Andre, SP (Brazil). Centro de Ciencias Naturais e Humanas; Lima, J.A.S. [Universidade de Sao Paulo (IAG/USP), SP (Brazil). Inst. de Astronomia, Geofisica e Ciencias Atmosfericas
2010-07-01
Full text: Stellar nucleosynthesis is widely accepted as the basic mechanism for creation of chemical elements in the Universe. In particular, nuclear reactions occurring in the Sun are recognized as responsible for its energy generation. The problem of to determine the energy generation mechanism in stars was firstly attacked by Gamow in the framework of his quantum mechanical theory of potential barrier penetration. According to that approach, the reactions rate is calculated by averaging the penetration factor over the velocity distribution of the plasma particles. A randomization of that distribution is expected as a consequence of the reactions. However, diffusion processes in the macroscopic environment should balance the resulting particles number depletion. Therefore, matter, energy, and momentum might steadily flow. In other words, a quasi-stationary equilibrium state must be attained. In this work, the potential barrier penetration approach to stellar nuclear reactions rate has been rediscussed with basis on Tsallis nonextensive statistics. The investigation has been restricted to non-resonant reactions, for which the S-factor can be regarded as a constant. It has been found that, within the extended formulation, the nonextensive q-parameter is constrained to a maximum value. Accordingly, the q-energy has been shown to exhibit a minimum. The q-Gamow peak has been derived and, in connection with the usual Gaussian approximation, the corresponding half q-width has been also estimated. Plots of the q-energy, q-Gamow peak and half q-width for some reactions with stellar physics interest have been produced. (author)
Isochronicity corrections for isochronous mass measurements at the HIRFL-CSRe
International Nuclear Information System (INIS)
Gao, Xiang; Yuan, You-Jin; Yang, Jian-cheng; Litvinov, S.; Wang, Meng; Litvinov, Y.; Zhang, Wei; Yin, Da-Yu; Shen, Guo-Dong; Chai, Wei-ping; Shi, Jian; Shang, Peng
2014-01-01
Isochronous Mass Spectrometry (IMS) is a unique experimental method for mass measurement experiments on short-lived nuclei. Mass measurements of 78 Kr projectile fragments were performed in HIRFL-CSRe at the Institute of Modern Physics (IMP), Chinese Academy of Sciences. The short-lived secondary beams were produced by bombarding a 15 mm thick beryllium-target in the Radioactive Ion Beam Line (RIBLL2) and were then injected into the CSRe storage ring. The masses of stored ions were measured by employing the IMS technique, which is based on the determination of the ion revolution times. A dedicated time-of-flight (TOF) detector is used for the latter purpose. However, the isochronicity, and thus the mass resolving power, depends on the momentum spread and the transverse emittance of the injected beams, Here, we present the first-order isochronicity optimization, the chromaticity and second-order isochronicity corrections through the modification of the quadrupole and sextupole field strengths. With the help of these corrections, the mass resolution of Δm/m=10 −6 can be achieved
Isochronicity corrections for isochronous mass measurements at the HIRFL-CSRe
Energy Technology Data Exchange (ETDEWEB)
Gao, Xiang [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Yuan, You-Jin; Yang, Jian-cheng [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Litvinov, S. [GSI, Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Wang, Meng [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Litvinov, Y. [GSI, Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Zhang, Wei; Yin, Da-Yu [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Shen, Guo-Dong [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Chai, Wei-ping; Shi, Jian [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Shang, Peng [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China)
2014-11-01
Isochronous Mass Spectrometry (IMS) is a unique experimental method for mass measurement experiments on short-lived nuclei. Mass measurements of {sup 78}Kr projectile fragments were performed in HIRFL-CSRe at the Institute of Modern Physics (IMP), Chinese Academy of Sciences. The short-lived secondary beams were produced by bombarding a 15 mm thick beryllium-target in the Radioactive Ion Beam Line (RIBLL2) and were then injected into the CSRe storage ring. The masses of stored ions were measured by employing the IMS technique, which is based on the determination of the ion revolution times. A dedicated time-of-flight (TOF) detector is used for the latter purpose. However, the isochronicity, and thus the mass resolving power, depends on the momentum spread and the transverse emittance of the injected beams, Here, we present the first-order isochronicity optimization, the chromaticity and second-order isochronicity corrections through the modification of the quadrupole and sextupole field strengths. With the help of these corrections, the mass resolution of Δm/m=10{sup −6} can be achieved.
MS vs. pole masses of gauge bosons II: Two-loop electroweak fermion correct
International Nuclear Information System (INIS)
Jegerlehner, F.; Kalmykov, M.Yu.; Veretin, O.
2002-12-01
We have calculated the fermion contributions to the shift of the position of the poles of the massive gauge boson propagators at two-loop order in the Standard Model. Together with the bosonic contributions calculated previously the full two-loop corrections are available. This allows us to investigate the full correction in the relationship between anti M anti S and pole masses of the vector bosons Z and W. Two-loop renormalization and the corresponding renormalization group equations are discussed. Analytical results for the master-integrals appearing in the massless fermion contributions are given. A new approach of summing multiple binomial sums has been developed. (orig.)
Radiative corrections to the quark masses in the ferromagnetic Ising and Potts field theories
Directory of Open Access Journals (Sweden)
Sergei B. Rutkevich
2017-10-01
Full Text Available We consider the Ising Field Theory (IFT, and the 3-state Potts Field Theory (PFT, which describe the scaling limits of the two-dimensional lattice q-state Potts model with q=2, and q=3, respectively. At zero magnetic field h=0, both field theories are integrable away from the critical point, have q degenerate vacua in the ferromagnetic phase, and q(q−1 particles of the same mass – the kinks interpolating between two different vacua. Application of a weak magnetic field induces confinement of kinks into bound states – the “mesons” (for q=2,3 consisting predominantly of two kinks, and “baryons” (for q=3, which are essentially the three-kink excitations. The kinks in the confinement regime are also called “the quarks”. We review and refine the Form Factor Perturbation Theory (FFPT, adapting it to the analysis of the confinement problem in the limit of small h, and apply it to calculate the corrections to the kink (quark masses induced by the multi-kink fluctuations caused by the weak magnetic field. It is shown that the subleading third-order ∼h3 correction to the kink mass vanishes in the IFT. The leading second order ∼h2 correction to the kink mass in the 3-state PFT is estimated by truncation the infinite form factor expansion at the first term representing contribution of the two-kink fluctuations into the kink self-energy.
Radiative corrections to the quark masses in the ferromagnetic Ising and Potts field theories
Rutkevich, Sergei B.
2017-10-01
We consider the Ising Field Theory (IFT), and the 3-state Potts Field Theory (PFT), which describe the scaling limits of the two-dimensional lattice q-state Potts model with q = 2, and q = 3, respectively. At zero magnetic field h = 0, both field theories are integrable away from the critical point, have q degenerate vacua in the ferromagnetic phase, and q (q - 1) particles of the same mass - the kinks interpolating between two different vacua. Application of a weak magnetic field induces confinement of kinks into bound states - the "mesons" (for q = 2 , 3) consisting predominantly of two kinks, and "baryons" (for q = 3), which are essentially the three-kink excitations. The kinks in the confinement regime are also called "the quarks". We review and refine the Form Factor Perturbation Theory (FFPT), adapting it to the analysis of the confinement problem in the limit of small h, and apply it to calculate the corrections to the kink (quark) masses induced by the multi-kink fluctuations caused by the weak magnetic field. It is shown that the subleading third-order ∼h3 correction to the kink mass vanishes in the IFT. The leading second order ∼h2 correction to the kink mass in the 3-state PFT is estimated by truncation the infinite form factor expansion at the first term representing contribution of the two-kink fluctuations into the kink self-energy.
Infinite nuclear matter model and mass formulae for nuclei
International Nuclear Information System (INIS)
Satpathy, L.
2016-01-01
The matter composed of the nucleus is a quantum-mechanical interacting many-fermionic system. However, the shell and classical liquid drop have been taken as the two main features of nuclear dynamics, which have guided the evolution of nuclear physics. These two features can be considered as the macroscopic manifestation of the microscopic dynamics of the nucleons at fundamental level. Various mass formulae have been developed based on either of these features over the years, resulting in many ambiguities and uncertainties posing many challenges in this field. Keeping this in view, Infinite Nuclear Matter (INM) model has been developed during last couple of decades with a many-body theoretical foundation employing the celebrated Hugenholtz-Van Hove theorem, quite appropriate for the interacting quantum-mechanical nuclear system. A mass formula called INM mass formula based on this model yields rms deviation of 342 keV being the lowest in literature. Some of the highlights of its result includes its determination of INM density in agreement with the electron scattering data leading to the resolution of the long standing 'r 0 -paradox' it predicts new magic numbers giving rise to new island of stability in the drip-line regions. This is the manifestation of a new phenomenon where shell-effect over comes the repulsive component of nucleon-nucleon force resulting in the broadening of the stability peninsula. Shell quenching in N= 82,and N= 126 shells, and several islands of inversion have been predicted. The model determines the empirical value of the nuclear compression modulus, using high precission 4500 data comprising nuclear masses, neutron and proton separation energies. The talk will give a critical review of the field of mass formula and our understanding of nuclear dynamics as a whole
Evaluation of corrective action data for reportable events at commercial nuclear power plants
International Nuclear Information System (INIS)
Mays, G.T.
1991-01-01
805The Nuclear Regulatory Commission (NRC) approved the adoption of cause codes for reportable events as a new performance indicator (PI) in March 1989. Corrective action data associated with the causes of events were to be compiled also. The corrective action data was considered as supplemental information but not identified formally as a performance indicator. In support of NRC, the Nuclear Operations Analysis Center (NOAC) at the Oak Ridge National Laboratory (ORNL) has been routinely evaluating licensee event reports (LERs) for cause code and corrective action data since 1989. The compilation of corrective action data by NOAC represents the first systematic and comprehensive compilation of this type data. The thrust of analyzing the corrective action data was to identify areas where licensees allocated resources to solve problems and prevent the recurrence of personnel errors and equipment failures. The predominant areas of corrective action reported by licensees are to be evaluated by NRC to compare with NRC programs designed to improve plant performance. The set of corrective action codes used to correlate with individual cause codes and included in the analyses were: training, procedural modification, corrective discipline, management change, design modification, equipment replacement/adjustment, other, and unknown. 1 fig
Validating neural-network refinements of nuclear mass models
Utama, R.; Piekarewicz, J.
2018-01-01
Background: Nuclear astrophysics centers on the role of nuclear physics in the cosmos. In particular, nuclear masses at the limits of stability are critical in the development of stellar structure and the origin of the elements. Purpose: We aim to test and validate the predictions of recently refined nuclear mass models against the newly published AME2016 compilation. Methods: The basic paradigm underlining the recently refined nuclear mass models is based on existing state-of-the-art models that are subsequently refined through the training of an artificial neural network. Bayesian inference is used to determine the parameters of the neural network so that statistical uncertainties are provided for all model predictions. Results: We observe a significant improvement in the Bayesian neural network (BNN) predictions relative to the corresponding "bare" models when compared to the nearly 50 new masses reported in the AME2016 compilation. Further, AME2016 estimates for the handful of impactful isotopes in the determination of r -process abundances are found to be in fairly good agreement with our theoretical predictions. Indeed, the BNN-improved Duflo-Zuker model predicts a root-mean-square deviation relative to experiment of σrms≃400 keV. Conclusions: Given the excellent performance of the BNN refinement in confronting the recently published AME2016 compilation, we are confident of its critical role in our quest for mass models of the highest quality. Moreover, as uncertainty quantification is at the core of the BNN approach, the improved mass models are in a unique position to identify those nuclei that will have the strongest impact in resolving some of the outstanding questions in nuclear astrophysics.
Estimation of unknown nuclear masses by means of the generalized mass relations. Pt. 3
International Nuclear Information System (INIS)
Popa, S.M.
1980-01-01
A survey of the estimations of the unknown nuclear masses by means of the generalized mass relations is presented. One discusses the new hypotheses supplementing the original general Garvey-Kelson scheme, reviewing the generalized mass relations and formulae, according to the present status of this new formalism. A critical discussions is given of the reliability of these new Garvey-Kelson type extrapolation procedures. (author)
Facing the challenge of nuclear mass tort processing
International Nuclear Information System (INIS)
Pelzer, Norbert
2017-01-01
A great majority of states do not issue any specific legislation on nuclear mass tort litigations. They apparently build on general traditional practice as most probably already tried and tested in other areas. Some states defer the decision on the way to deal with mass tort claims to the time of the nuclear incident. They insert into their nuclear liability laws respective 'reminders' that contain an invitation or a demand to the legislator to take appropriate steps if and when necessary. Finally, there are a number of states that enacted elaborate regimes on how to react to, and organise, compensation of mass damages after a catastrophic nuclear incident. Among those states are in particular major nuclear states like Canada, India, Japan and the US. They developed compensation schemes where claims for compensation of nuclear damage shall be dealt with by fora that are not regular courts. In some of those states, the fora are exclusively competent without a right to appeal their decisions, while in other states the fora act in parallel or in complement to courts. So the international scenario appears to be somewhat confusing. Of course, sovereign states are free to organise claims processing, including nuclear mass claims processing, as they deem fit. The discretion of states is, however, limited by obligations under public international law. With regard to the victims of nuclear incidents, states are particularly bound by obligations under the 1948 Universal Declaration of Human Rights and other relevant instruments they may be a party to. National nuclear mass claim processing has in particular to comply with the obligation to guarantee 'a fair and public hearing by an independent and impartial tribunal'. With regard to possible international obligations vis-a-vis other states, it has to be taken into account that major nuclear incidents, as a rule, have transboundary detrimental effects. There is always a potential impact on territories
2002-01-01
Tile Calorimeter modules stored at CERN. The larger modules belong to the Barrel, whereas the smaller ones are for the two Extended Barrels. (The article was about the completion of the 64 modules for one of the latter.) The photo on the first page of the Bulletin n°26/2002, from 24 July 2002, illustrating the article «The ATLAS Tile Calorimeter gets into shape» was published with a wrong caption. We would like to apologise for this mistake and so publish it again with the correct caption.
Masses of exotic calcium isotopes pin down nuclear forces
Wienholtz, F; Blaum, K; Borgmann, Ch; Breitenfeldt, M; Cakirli, R B; George, S; Herfurth, F; Holt, J D; Kowalska, M; Kreim, S; Lunney, D; Manea, V; Menéndez, J; Neidherr, D; Rosenbusch, M; Schweikhard, L; Schwenk, A; Simonis, J; Stanja, J; Wolf, R N; Zuber, K
2013-01-01
The properties of exotic nuclei on the verge of existence play a fundamental part in our understanding of nuclear interactions. Exceedingly neutron-rich nuclei become sensitive to new aspects of nuclear forces. Calcium, with its doubly magic isotopes $^{40}$Ca and $^{48}$Ca, is an ideal test for nuclear shell evolution, from the valley of stability to the limits of existence. With a closed proton shell, the calcium isotopes mark the frontier for calculations with three-nucleon forces from chiral effective field theory. Whereas predictions for the masses of $^{51}$Ca and $^{52}$Ca have been validated by direct measurements$^4$, it is an open question as to how nuclear masses evolve for heavier calcium isotopes. Here we report the mass determination of the exotic calcium isotopes $^{53}$Ca and $^{54}$Ca, using the multi-reflection time-of-flight mass spectrometer of ISOLTRAP at CERN. The measured masses unambiguously establish a prominent shell closure at neutron number N = 32, in excellent agreement with our t...
Dependence of X-Ray Burst Models on Nuclear Masses
Energy Technology Data Exchange (ETDEWEB)
Schatz, H.; Ong, W.-J. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824 (United States)
2017-08-01
X-ray burst model predictions of light curves and the final composition of the nuclear ashes are affected by uncertain nuclear masses. However, not all of these masses are determined experimentally with sufficient accuracy. Here we identify the remaining nuclear mass uncertainties in X-ray burst models using a one-zone model that takes into account the changes in temperature and density evolution caused by changes in the nuclear physics. Two types of bursts are investigated—a typical mixed H/He burst with a limited rapid proton capture process (rp-process) and an extreme mixed H/He burst with an extended rp-process. When allowing for a 3 σ variation, only three remaining nuclear mass uncertainties affect the light-curve predictions of a typical H/He burst ({sup 27}P, {sup 61}Ga, and {sup 65}As), and only three additional masses affect the composition strongly ({sup 80}Zr, {sup 81}Zr, and {sup 82}Nb). A larger number of mass uncertainties remain to be addressed for the extreme H/He burst, with the most important being {sup 58}Zn, {sup 61}Ga, {sup 62}Ge, {sup 65}As, {sup 66}Se, {sup 78}Y, {sup 79}Y, {sup 79}Zr, {sup 80}Zr, {sup 81}Zr, {sup 82}Zr, {sup 82}Nb, {sup 83}Nb, {sup 86}Tc, {sup 91}Rh, {sup 95}Ag, {sup 98}Cd, {sup 99}In, {sup 100}In, and {sup 101}In. The smallest mass uncertainty that still impacts composition significantly when varied by 3 σ is {sup 85}Mo with 16 keV uncertainty. For one of the identified masses, {sup 27}P, we use the isobaric mass multiplet equation to improve the mass uncertainty, obtaining an atomic mass excess of −716(7) keV. The results provide a roadmap for future experiments at advanced rare isotope beam facilities, where all the identified nuclides are expected to be within reach for precision mass measurements.
Theories of Variable Mass Particles and Low Energy Nuclear Phenomena
Davidson, Mark
2014-02-01
Variable particle masses have sometimes been invoked to explain observed anomalies in low energy nuclear reactions (LENR). Such behavior has never been observed directly, and is not considered possible in theoretical nuclear physics. Nevertheless, there are covariant off-mass-shell theories of relativistic particle dynamics, based on works by Fock, Stueckelberg, Feynman, Greenberger, Horwitz, and others. We review some of these and we also consider virtual particles that arise in conventional Feynman diagrams in relativistic field theories. Effective Lagrangian models incorporating variable mass particle theories might be useful in describing anomalous nuclear reactions by combining mass shifts together with resonant tunneling and other effects. A detailed model for resonant fusion in a deuterium molecule with off-shell deuterons and electrons is presented as an example. Experimental means of observing such off-shell behavior directly, if it exists, is proposed and described. Brief explanations for elemental transmutation and formation of micro-craters are also given, and an alternative mechanism for the mass shift in the Widom-Larsen theory is presented. If variable mass theories were to find experimental support from LENR, then they would undoubtedly have important implications for the foundations of quantum mechanics, and practical applications may arise.
Directory of Open Access Journals (Sweden)
2012-01-01
Full Text Available Regarding Gorelik, G., & Shackelford, T.K. (2011. Human sexual conflict from molecules to culture. Evolutionary Psychology, 9, 564–587: The authors wish to correct an omission in citation to the existing literature. In the final paragraph on p. 570, we neglected to cite Burch and Gallup (2006 [Burch, R. L., & Gallup, G. G., Jr. (2006. The psychobiology of human semen. In S. M. Platek & T. K. Shackelford (Eds., Female infidelity and paternal uncertainty (pp. 141–172. New York: Cambridge University Press.]. Burch and Gallup (2006 reviewed the relevant literature on FSH and LH discussed in this paragraph, and should have been cited accordingly. In addition, Burch and Gallup (2006 should have been cited as the originators of the hypothesis regarding the role of FSH and LH in the semen of rapists. The authors apologize for this oversight.
2002-01-01
The photo on the second page of the Bulletin n°48/2002, from 25 November 2002, illustrating the article «Spanish Visit to CERN» was published with a wrong caption. We would like to apologise for this mistake and so publish it again with the correct caption. The Spanish delegation, accompanied by Spanish scientists at CERN, also visited the LHC superconducting magnet test hall (photo). From left to right: Felix Rodriguez Mateos of CERN LHC Division, Josep Piqué i Camps, Spanish Minister of Science and Technology, César Dopazo, Director-General of CIEMAT (Spanish Research Centre for Energy, Environment and Technology), Juan Antonio Rubio, ETT Division Leader at CERN, Manuel Aguilar-Benitez, Spanish Delegate to Council, Manuel Delfino, IT Division Leader at CERN, and Gonzalo León, Secretary-General of Scientific Policy to the Minister.
Directory of Open Access Journals (Sweden)
2014-01-01
Full Text Available Regarding Tagler, M. J., and Jeffers, H. M. (2013. Sex differences in attitudes toward partner infidelity. Evolutionary Psychology, 11, 821–832: The authors wish to correct values in the originally published manuscript. Specifically, incorrect 95% confidence intervals around the Cohen's d values were reported on page 826 of the manuscript where we reported the within-sex simple effects for the significant Participant Sex × Infidelity Type interaction (first paragraph, and for attitudes toward partner infidelity (second paragraph. Corrected values are presented in bold below. The authors would like to thank Dr. Bernard Beins at Ithaca College for bringing these errors to our attention. Men rated sexual infidelity significantly more distressing (M = 4.69, SD = 0.74 than they rated emotional infidelity (M = 4.32, SD = 0.92, F(1, 322 = 23.96, p < .001, d = 0.44, 95% CI [0.23, 0.65], but there was little difference between women's ratings of sexual (M = 4.80, SD = 0.48 and emotional infidelity (M = 4.76, SD = 0.57, F(1, 322 = 0.48, p = .29, d = 0.08, 95% CI [−0.10, 0.26]. As expected, men rated sexual infidelity (M = 1.44, SD = 0.70 more negatively than they rated emotional infidelity (M = 2.66, SD = 1.37, F(1, 322 = 120.00, p < .001, d = 1.12, 95% CI [0.85, 1.39]. Although women also rated sexual infidelity (M = 1.40, SD = 0.62 more negatively than they rated emotional infidelity (M = 2.09, SD = 1.10, this difference was not as large and thus in the evolutionary theory supportive direction, F(1, 322 = 72.03, p < .001, d = 0.77, 95% CI [0.60, 0.94].
Directory of Open Access Journals (Sweden)
Rui Wang
2017-10-01
Full Text Available We establish a relation between the equation of state of nuclear matter and the fourth-order symmetry energy asym,4(A of finite nuclei in a semi-empirical nuclear mass formula by self-consistently considering the bulk, surface and Coulomb contributions to the nuclear mass. Such a relation allows us to extract information on nuclear matter fourth-order symmetry energy Esym,4(ρ0 at normal nuclear density ρ0 from analyzing nuclear mass data. Based on the recent precise extraction of asym,4(A via the double difference of the “experimental” symmetry energy extracted from nuclear masses, for the first time, we estimate a value of Esym,4(ρ0=20.0±4.6 MeV. Such a value of Esym,4(ρ0 is significantly larger than the predictions from mean-field models and thus suggests the importance of considering the effects of beyond the mean-field approximation in nuclear matter calculations.
Equidistant structure and effective nucleon mass in nuclear matter
International Nuclear Information System (INIS)
Tezuka, Hirokazu.
1981-11-01
The effective nucleon mass of the Equidistant Multi-Layer Structure (EMULS) is discussed self-consistently. In the density region where the Fermi gas state in nuclear matter is unstable against the density fluctuation, the EMULS gives lower binding energy. It is, however, shown that such a structure with an ordinary nucleon mass collapses due to too strong attraction. We point out that such a collapse can be avoided by taking account of an effective nucleon mass affected by the localization of nucleons. (author)
Nuclear reactions of high energy deuterons with medium mass targets
International Nuclear Information System (INIS)
Numajiri, Masaharu; Miura, Taichi; Oki, Yuichi
1994-01-01
Formation cross sections of product nuclides in the nuclear reactions of medium mass targets by 10 GeV deuterons were measured with a gamma-ray spectroscopy. The measured data were compared with the cross sections of 12 GeV protons. (author)
Role of mass spectrometry in nuclear forensic science
International Nuclear Information System (INIS)
Joseph, M.; Sivaraman, N.
2016-01-01
The present talk will focus on the role of mass spectrometry in NFS in general; besides that, the various chromatographic methods developed towards separation of actinides and lanthanide fission products and characterization of dissolver solutions of nuclear reactor fuels using TIMS and some applications of using ICP-MS as well
Extrapolations of nuclear binding energies from new linear mass relations
DEFF Research Database (Denmark)
Hove, D.; Jensen, A. S.; Riisager, K.
2013-01-01
We present a method to extrapolate nuclear binding energies from known values for neighboring nuclei. We select four specific mass relations constructed to eliminate smooth variation of the binding energy as function nucleon numbers. The fast odd-even variations are avoided by comparing nuclei...
The nuclear waste issue in Swedish mass media
International Nuclear Information System (INIS)
Hedberg, P.
1991-04-01
This is an investigation of the representation given in the Swedish mass media of questions concerning the nuclear waste. The investigation covers the period from 1979 to 1989 of 8 newspapers of different political colours and the Swedish radio and television. (KAE)
Improved Nuclear Reactor and Shield Mass Model for Space Applications
Robb, Kevin
2004-01-01
New technologies are being developed to explore the distant reaches of the solar system. Beyond Mars, solar energy is inadequate to power advanced scientific instruments. One technology that can meet the energy requirements is the space nuclear reactor. The nuclear reactor is used as a heat source for which a heat-to-electricity conversion system is needed. Examples of such conversion systems are the Brayton, Rankine, and Stirling cycles. Since launch cost is proportional to the amount of mass to lift, mass is always a concern in designing spacecraft. Estimations of system masses are an important part in determining the feasibility of a design. I worked under Michael Barrett in the Thermal Energy Conversion Branch of the Power & Electric Propulsion Division. An in-house Closed Cycle Engine Program (CCEP) is used for the design and performance analysis of closed-Brayton-cycle energy conversion systems for space applications. This program also calculates the system mass including the heat source. CCEP uses the subroutine RSMASS, which has been updated to RSMASS-D, to estimate the mass of the reactor. RSMASS was developed in 1986 at Sandia National Laboratories to quickly estimate the mass of multi-megawatt nuclear reactors for space applications. In response to an emphasis for lower power reactors, RSMASS-D was developed in 1997 and is based off of the SP-100 liquid metal cooled reactor. The subroutine calculates the mass of reactor components such as the safety systems, instrumentation and control, radiation shield, structure, reflector, and core. The major improvements in RSMASS-D are that it uses higher fidelity calculations, is easier to use, and automatically optimizes the systems mass. RSMASS-D is accurate within 15% of actual data while RSMASS is only accurate within 50%. My goal this summer was to learn FORTRAN 77 programming language and update the CCEP program with the RSMASS-D model.
Influence of conservative corrections on parameter estimation for extreme-mass-ratio inspirals
International Nuclear Information System (INIS)
Huerta, E. A.; Gair, Jonathan R.
2009-01-01
We present an improved numerical kludge waveform model for circular, equatorial extreme-mass-ratio inspirals (EMRIs). The model is based on true Kerr geodesics, augmented by radiative self-force corrections derived from perturbative calculations, and in this paper for the first time we include conservative self-force corrections that we derive by comparison to post-Newtonian results. We present results of a Monte Carlo simulation of parameter estimation errors computed using the Fisher matrix and also assess the theoretical errors that would arise from omitting the conservative correction terms we include here. We present results for three different types of system, namely, the inspirals of black holes, neutron stars, or white dwarfs into a supermassive black hole (SMBH). The analysis shows that for a typical source (a 10M · compact object captured by a 10 6 M · SMBH at a signal to noise ratio of 30) we expect to determine the two masses to within a fractional error of ∼10 -4 , measure the spin parameter q to ∼10 -4.5 , and determine the location of the source on the sky and the spin orientation to within 10 -3 steradians. We show that, for this kludge model, omitting the conservative corrections leads to a small error over much of the parameter space, i.e., the ratio R of the theoretical model error to the Fisher matrix error is R<1 for all ten parameters in the model. For the few systems with larger errors typically R<3 and hence the conservative corrections can be marginally ignored. In addition, we use our model and first-order self-force results for Schwarzschild black holes to estimate the error that arises from omitting the second-order radiative piece of the self-force. This indicates that it may not be necessary to go beyond first order to recover accurate parameter estimates.
International Nuclear Information System (INIS)
Ellis, J.; Zwirner, F.
1991-01-01
We present calculations of the one-loop radiative corrections to the mass of the neutral CP-odd Higgs boson (A) in the minimal supersymmetric extension of the standard model, as well as to the neutral CP-even Higgs (h, H) masses and mixing angles. We use these results to recalculate the cross-sections for Higgs production at LEP in the h + (Z * + fanti f), h (H)Z 0 and h (H) A final states. We delineate the domains of parameter space accessible at LEP at the Z 0 peak and at LEP II with a center-of-mass energy of 180, 190 or 200 GeV. (orig.)
Center-of-mass correction and confinement radii of the composite vector bosons
International Nuclear Information System (INIS)
Tadic, D.; Tadic, G.
1985-01-01
Describing a composite W boson by a center-of-mass--corrected bag model one finds a relation R/sub W/ 3 M/sub W/ 3 / f/sub W/ 2 approx. =R/sub rho/ 3 m/sub rho/ 3 / f/sub rho/ 2 for the confinement radii (R), masses, and coupling constants (f) of W and rho bosons. Using experimental values for f/sub rho/, m/sub rho/, and M/sub W/ and with f/sub W/ = 0.66, one obtains R/sub W//R/sub rho/approx. =2 x 10 -3 . f/sub rho/, f/sub W/, and masses can be calculated separately
Two-loop corrections for nuclear matter in the Walecka model
International Nuclear Information System (INIS)
Furnstahl, R.J.; Perry, R.J.; Serot, B.D.; Department of Physics, The Ohio State University, Columbus, Ohio 43210; Physics Department and Nuclear Theory Center, Indiana University, Bloomington, Indiana 47405)
1989-01-01
Two-loop corrections for nuclear matter, including vacuum polarization, are calculated in the Walecka model to study the loop expansion as an approximation scheme for quantum hadrodynamics. Criteria for useful approximation schemes are discussed, and the concepts of strong and weak convergence are introduced. The two-loop corrections are evaluated first with one-loop parameters and mean fields and then by minimizing the total energy density with respect to the scalar field and refitting parameters to empirical nuclear matter saturation properties. The size and nature of the corrections indicate that the loop expansion is not convergent at two-loop order in either the strong or weak sense. Prospects for alternative approximation schemes are discussed
Standardized uptake value of FDG corrected by lean body mass measured by DEXA
International Nuclear Information System (INIS)
Guirao, M.A.; Sanchez, A.M.; Saravi, F.D.; Mosconi, S.; Frias, L.
2002-01-01
Evaluating the metabolic activity of tumor lesion sometimes becomes important to evaluate grading of malignancy, prognosis, or response to therapy. The most used measure of the metabolic activity of [18F]-Fluorodeoxiglucose (FDG) in clinical PET is the Standardized Uptake Value (SUV). It relates the activity measured by the PET scan to the injected dose of FDG divided by the body mass. This approach overestimates SUV in 'heavy' patients, as the proportion of the 'low avid of FDG' fat mass increases. For this reason, different approaches are being evaluated to obtain a more accurate SUV measure. Aims: to compare the measured lean body mass by Dual X-Ray Absorptiometry with the previous methods of correction, to assess the more independent to the body constitution. Material and Methods: FDG metabolism was studied to 15 patients of both sexes, age between 28 and 72 y.o., body weight 55 to 92 Kg. One hour after the IV injection of 0.0045mCi/Kg of FDG, a whole body emission and transmission scan was performed to each subject in a positron emission tomograph (QUEST 250, GE-UGM, USA) for over 1 hour. Body lean mass composition was measured the same or next day by DEXA (Lunar DPX-L, USA.) ROIs were drawn on brain, liver and muscle. SUVbw =[(corrected mCi/g of tissue) / (mCi injected / body weight in grams)] was calculated for each tissue, and then recalculated replacing body weight with the measured lean body mass (SUVlm), calculated lean mass (SUVlc), body mass index (SUVmi) and body surface area (SUVsa). Corrected SUVs were normalized to each SUVbw average for a comparable visualization of results. Results: obtained data was analyzed by linear regression and curve estimation for each case in all tissues with the SPSS statistical software. A positive correlation between SUVbw and subject weight was confirmed for the 3 tissues. In Muscle and liver there was no significant correlation. The liver scanning time was variable ( 90 to 123 minutes after injection). Relating liver
Toth, Ronald T; Mills, Brittney J; Joshi, Sangeeta B; Esfandiary, Reza; Bishop, Steven M; Middaugh, C Russell; Volkin, David B; Weis, David D
2017-09-05
A barrier to the use of hydrogen exchange-mass spectrometry (HX-MS) in many contexts, especially analytical characterization of various protein therapeutic candidates, is that differences in temperature, pH, ionic strength, buffering agent, or other additives can alter chemical exchange rates, making HX data gathered under differing solution conditions difficult to compare. Here, we present data demonstrating that HX chemical exchange rates can be substantially altered not only by the well-established variables of temperature and pH but also by additives including arginine, guanidine, methionine, and thiocyanate. To compensate for these additive effects, we have developed an empirical method to correct the hydrogen-exchange data for these differences. First, differences in chemical exchange rates are measured by use of an unstructured reporter peptide, YPI. An empirical chemical exchange correction factor, determined by use of the HX data from the reporter peptide, is then applied to the HX measurements obtained from a protein of interest under different solution conditions. We demonstrate that the correction is experimentally sound through simulation and in a proof-of-concept experiment using unstructured peptides under slow-exchange conditions (pD 4.5 at ambient temperature). To illustrate its utility, we applied the correction to HX-MS excipient screening data collected for a pharmaceutically relevant IgG4 mAb being characterized to determine the effects of different formulations on backbone dynamics.
Properties of nuclear matter from macroscopic–microscopic mass formulas
Directory of Open Access Journals (Sweden)
Ning Wang
2015-12-01
Full Text Available Based on the standard Skyrme energy density functionals together with the extended Thomas–Fermi approach, the properties of symmetric and asymmetric nuclear matter represented in two macroscopic–microscopic mass formulas: Lublin–Strasbourg nuclear drop energy (LSD formula and Weizsäcker–Skyrme (WS* formula, are extracted through matching the energy per particle of finite nuclei. For LSD and WS*, the obtained incompressibility coefficients of symmetric nuclear matter are K∞=230±11 MeV and 235±11 MeV, respectively. The slope parameter of symmetry energy at saturation density is L=41.6±7.6 MeV for LSD and 51.5±9.6 MeV for WS*, respectively, which is compatible with the liquid-drop analysis of Lattimer and Lim [4]. The density dependence of the mean-field isoscalar and isovector effective mass, and the neutron–proton effective masses splitting for neutron matter are simultaneously investigated. The results are generally consistent with those from the Skyrme Hartree–Fock–Bogoliubov calculations and nucleon optical potentials, and the standard deviations are large and increase rapidly with density. A better constraint for the effective mass is helpful to reduce uncertainties of the depth of the mean-field potential.
Infinite nuclear matter based for mass of atomic nuclei
International Nuclear Information System (INIS)
Satpathy, L.
1987-01-01
The ground-state energy of an atomic nucleus with asymmetry β is considered to be equivalent to the energy of a perfect sphere made up of infinite nuclear matter of the same asymmetry plus a residual energy eta, called the local energy. Eta represents the energy due to shell, deformation, diffuseness and exchange Coulomb effects, etc. Using this picture and the generalised Hugenholtz-Van Hove theorem of many-body theory, the previously proposed mass relation is derived in a transport way in which eta drops away in a very natural manner. The validity of this mass relation is studied globally using the latest mass table. The model is suitable for the extraction of the saturation properties of nuclear matter. The binding energy per nucleon and the saturation Fermi momentum of nuclear matter obtained through this model are 18.33 MeV and 1.48 fm -1 respectively. It is shown in several representative cases in the Periodic Table that the masses of nuclei in the far unknown region can be reliably predicted. (author)
Use of mass and toxicity balances in risk-based corrective action decisions at contaminated sites
International Nuclear Information System (INIS)
Sevigny, J.H.; Lintott, D.; Wrubleski, R.M.; Drury, C.R.
1997-01-01
The contaminated groundwater at a sour gas plant facility was studied to identify the chemicals of environmental concern. Simple mass balance principles were used to determine the proportion of organic carbon, organic nitrogen and Microtox R toxicity that can be attributed to two process chemicals that have contaminated several sour gas plants in western Canada. The two process chemicals are sulfolane and diisopropanolamine (DIPA). The organic carbon balance was calculated by determining the molar contribution of sulfolane and DIPA relative to the mass of carboxylic acid-corrected dissolved organic carbon. Organic carbon balances ranged from 44 to 96 per cent. The organic nitrogen balance was calculated by determining the molar contribution of DIPA relative to the mass of ammonium ion-corrected dissolved Kjeldahl nitrogen. The nitrogen balances were highly variable between 8 to 48 per cent for samples with organic nitrogen concentrations between 10 and 32 mg/L. The Microtox R toxicity balance was calculated by determining the proportions of toxicity that could be accounted for by pure phase sulfolane and DIPA. The Microtox R toxicity balance for samples that showed significant toxicity ranged from 71 to 122 per cent
Mass-corrections for the conservative coupling of flow and transport on collocated meshes
Energy Technology Data Exchange (ETDEWEB)
Waluga, Christian, E-mail: waluga@ma.tum.de [Institute for Numerical Mathematics (M2), Technische Universität München, Boltzmannstraße 3, D-85748 Garching bei München (Germany); Wohlmuth, Barbara [Institute for Numerical Mathematics (M2), Technische Universität München, Boltzmannstraße 3, D-85748 Garching bei München (Germany); Rüde, Ulrich [Department of Computer Science 10, University Erlangen–Nuremberg, Cauerstr. 11, D-91058 Erlangen (Germany)
2016-01-15
Buoyancy-driven flow models demand a careful treatment of the mass-balance equation to avoid spurious source and sink terms in the non-linear coupling between flow and transport. In the context of finite-elements, it is therefore commonly proposed to employ sufficiently rich pressure spaces, containing piecewise constant shape functions to obtain local or even strong mass-conservation. In three-dimensional computations, this usually requires nonconforming approaches, special meshes or higher order velocities, which make these schemes prohibitively expensive for some applications and complicate the implementation into legacy code. In this paper, we therefore propose a lean and conservatively coupled scheme based on standard stabilized linear equal-order finite elements for the Stokes part and vertex-centered finite volumes for the energy equation. We show that in a weak mass-balance it is possible to recover exact conservation properties by a local flux-correction which can be computed efficiently on the control volume boundaries of the transport mesh. We discuss implementation aspects and demonstrate the effectiveness of the flux-correction by different two- and three-dimensional examples which are motivated by geophysical applications.
Use of mass and toxicity balances in risk-based corrective action decisions at contaminated sites
Energy Technology Data Exchange (ETDEWEB)
Sevigny, J.H. [Komex Consultants Ltd., Calgary, AB (Canada); Lintott, D. [HydroQual Consultants, Inc., Calgary, AB (Canada); Wrubleski, R.M.; Drury, C.R. [Shell Canada Ltd., Calgary, AB (Canada). Calgary Research Centre
1997-12-31
The contaminated groundwater at a sour gas plant facility was studied to identify the chemicals of environmental concern. Simple mass balance principles were used to determine the proportion of organic carbon, organic nitrogen and Microtox{sup R} toxicity that can be attributed to two process chemicals that have contaminated several sour gas plants in western Canada. The two process chemicals are sulfolane and diisopropanolamine (DIPA). The organic carbon balance was calculated by determining the molar contribution of sulfolane and DIPA relative to the mass of carboxylic acid-corrected dissolved organic carbon. Organic carbon balances ranged from 44 to 96 per cent. The organic nitrogen balance was calculated by determining the molar contribution of DIPA relative to the mass of ammonium ion-corrected dissolved Kjeldahl nitrogen. The nitrogen balances were highly variable between 8 to 48 per cent for samples with organic nitrogen concentrations between 10 and 32 mg/L. The Microtox{sup R} toxicity balance was calculated by determining the proportions of toxicity that could be accounted for by pure phase sulfolane and DIPA. The Microtox{sup R} toxicity balance for samples that showed significant toxicity ranged from 71 to 122 per cent.
Nuclear mass formulas and its application for astrophysics
International Nuclear Information System (INIS)
Koura, Hiroyuki
2003-01-01
Some nuclear mass formulae are reviewed and applied for the calculation of the rapid neutron-capture-process (r-process) nucleosynthesis. A new mass formula composed of the gross term, the even-odd term, and the shell term is also presented. The new mass formula is a revised version of the spherical basis mass formula published in 2001, that is, the even-odd term is treated more carefully, and a considerable improvement is brought about. The root-mean-square deviation of the new formula from experimental masses is 641 keV for Z ≥ 8 and N ≥ 8. Properties on systematic of the neutron-separation energy is compared with some mass formulas. The calculated abundances of the r-process from different mass formulae are compared with use of a simple reaction model, and the relation between the calculated abundances and the corresponding masses are discussed. Furthermore, fission barriers for the superheavy and neutron-rich nuclei are also applied for the endpoint of the r-process. (author)
Directory of Open Access Journals (Sweden)
A. Vlasenko
2010-08-01
Full Text Available Formaldehyde measurements can provide useful information about photochemical activity in ambient air, given that HCHO is formed via numerous oxidation processes. Proton transfer reaction mass spectrometry (PTR-MS is an online technique that allows measurement of VOCs at the sub-ppbv level with good time resolution. PTR-MS quantification of HCHO is hampered by the humidity dependence of the instrument sensitivity, with higher humidity leading to loss of PTR-MS signal. In this study we present an analytical, first principles approach to correct the PTR-MS HCHO signal according to the concentration of water vapor in sampled air. The results of the correction are validated by comparison of the PTR-MS results to those from a Hantzsch fluorescence monitor which does not have the same humidity dependence. Results are presented for an intercomparison made during a field campaign in rural Ontario at Environment Canada's Centre for Atmospheric Research Experiments.
Analytical expressions for radiatively corrected Higgs masses and couplings in the MSSM
International Nuclear Information System (INIS)
Carena, M.
1995-03-01
We propose, for the computation of the Higgs mass spectrum and couplings, a renormalization-group improved leading-log approximation, where the renormalization scale is fixed to the top-quark pole mass. For the case m A ∝M SUSY , our leading-log approximation differs by less than 2 GeV from previous results on the Higgs mass computed using a nearly scale independent renormalization-group improved effective potential up to next-to-leading order. Moreover, for the general case m A SUSY , we provide analytical formulae (including two-loop leading-log corrections) for all the masses and couplings in the Higgs sector. For M SUSY A , tan β and the stop mixing parameters, they reproduce the numerical renormalization-group improved leading-log result for the Higgs masses with an error of less than 3 GeV. For the Higgs couplings, our analytical formulae reproduce the numerical results equally well. Comparison with other methods is also performed. (orig.)
Mass shift of σ-meson in nuclear matter
International Nuclear Information System (INIS)
Morones-Ibarra, J.R.; Maciel, Mónica Menchaca; Padilla, Felipe Robledo; Santos-Guevara, Ayax
2013-01-01
The propagation of σ-meson in nuclear matter is studied in the Walecka model, by assuming that sigma couples to a pair of nucleon-antinucleon states to particle-hole states. The in-medium effect of σ-ω mixing is also studied. For completeness, the coupling of sigma to two virtual pions was also considered. It is found that the σ-meson mass decreases with respect to its value in vacuum and that the contribution of the σ-ω mixing effect on the mass shift is relatively small. (author)
Unified model of nuclear mass and level density formulas
International Nuclear Information System (INIS)
Nakamura, Hisashi
2001-01-01
The objective of present work is to obtain a unified description of nuclear shell, pairing and deformation effects for both ground state masses and level densities, and to find a new set of parameter systematics for both the mass and the level density formulas on the basis of a model for new single-particle state densities. In this model, an analytical expression is adopted for the anisotropic harmonic oscillator spectra, but the shell-pairing correlation are introduced in a new way. (author)
Consideration of possible mass and velocity corrections to magnetic cluster experiments
International Nuclear Information System (INIS)
Liu, Z.Y.; Dowben, P.A.; Popov, A.P.; Pappas, David P.
2003-01-01
Gadolinium occurs, in natural abundance, as several isotopes. The possible combinations of different gadolinium isotopes dictates that even for a fixed number of atoms in the cluster, clusters of gadolinium atoms will exhibit a range of masses. This and the expected consequence of the translation energy distributions are explored as possible corrections to Stern-Gerlach cluster beam-deflection experiments. Upon closer inspection of the experimental data, we find that the translation energy plus the vibrational temperature distribution may be inhomogeneous. This could be the origin of a long tail to high deflections in the experimental deflection profiles, at low cluster temperatures, in the magnetic cluster Stern-Gerlach experiments
Thomas-Fermi approach to nuclear mass formula. Pt. 1
International Nuclear Information System (INIS)
Dutta, A.K.; Arcoragi, J.P.; Pearson, J.M.; Tondeur, F.
1986-01-01
With a view to having a more secure basis for the nuclear mass formula than is provided by the drop(let) model, we make a preliminary study of the possibilities offered by the Skyrme-ETF method. Two ways of incorporating shell effects are considered: the ''Strutinsky-integral'' method of Chu et al., and the ''expectation-value'' method of Brack et al. Each of these methods is compared with the HF method in an attempt to see how reliably they extrapolate from the known region of the nuclear chart out to the neutron-drip line. The Strutinsky-integral method is shown to perform particularly well, and to offer a promising approach to a more reliable mass formula. (orig.)
Two-Loop Self-Energy Correction in a Strong Coulomb Nuclear Field
International Nuclear Information System (INIS)
Yerokhin, V.A.; Indelicato, P.; Shabaev, V.M.
2005-01-01
The two-loop self-energy correction to the ground-state energy levels of hydrogen-like ions with nuclear charges Z ≥ 10 is calculated without the Zα expansion, where α is the fine-structure constant. The data obtained are compared with the results of analytical calculations within the Zα expansion; significant disagreement with the analytical results of order α 2 (Zα) 6 has been found. Extrapolation is used to obtain the most accurate value for the two-loop self-energy correction for the 1s state in hydrogen
Quark and lepton masses at the GUT scale including supersymmetric threshold corrections
International Nuclear Information System (INIS)
Antusch, S.; Spinrath, M.
2008-01-01
We investigate the effect of supersymmetric (SUSY) threshold corrections on the values of the running quark and charged lepton masses at the grand unified theory (GUT) scale within the large tanβ regime of the minimal supersymmetric standard model. In addition to the typically dominant SUSY QCD contributions for the quarks, we also include the electroweak contributions for quarks and leptons and show that they can have significant effects. We provide the GUT scale ranges of quark and charged lepton Yukawa couplings as well as of the ratios m μ /m s , m e /m d , y τ /y b and y t /y b for three example ranges of SUSY parameters. We discuss how the enlarged ranges due to threshold effects might open up new possibilities for constructing GUT models of fermion masses and mixings.
Mass shift of σ-meson in nuclear matter
Indian Academy of Sciences (India)
Mass shift of σ-meson in nuclear matter. J R MORONES-IBARRA1, MÓNICA MENCHACA MACIEL1,∗. ,. AYAX SANTOS-GUEVARA2 and FELIPE ROBLEDO PADILLA1. 1Facultad de Ciencias Físico-Matemáticas, Universidad Autónoma de Nuevo León, UANL,. Av. Universidad S/N Ciudad Universitaria, San Nicolás de los ...
A quadrupole mass spectrometer system for nuclear safeguards applications
International Nuclear Information System (INIS)
Evans, P.J.
1987-12-01
An on-line enrichment monitor for nuclear safeguards-related surveillance of a pilot-scale gas centrifuge plant is described. This monitor utilises a quadrupole mass spectrometer to measure the isotopic composition of UF 6 in the feed and product gas streams. Details of the design and construction are given, and several difficulties are identified and discussed. Finally, the performance of this system is illustrated with typical results
HVP contributions to the muon (g−2 including QED corrections with twisted-mass fermions
Directory of Open Access Journals (Sweden)
Giusti Davide
2018-01-01
Full Text Available We present a lattice calculation of the Hadronic Vacuum Polarization (HVP contribution of the strange and charm quarks to the anomalous magnetic moment of the muon including leading-order electromagnetic (e.m. corrections. We employ the gauge configurations generated by the European Twisted Mass Collaboration (ETMC with Nf = 2+1 + 1 dynamical quarks at three values of the lattice spacing (a ≃ 0.062,0.082,0.089 fm with pion masses in the range Mπ ≃ 210 - 450 MeV. The strange and charm quark masses are tuned at their physical values. Neglecting discon-nected diagrams and after the extrapolations to the physical pion mass and to the continuum limit we obtain: aμsαem2=53.1±2.5⋅10−10,aμsαem3=−0.018±0.011⋅10−10 and aμcαem2=14.75±0.56⋅10−10,aμcαem3=−0.030±0.013⋅10−10 for the strange and charm contributions, respectively.!
HVP contributions to the muon (g-2) including QED corrections with twisted-mass fermions
Giusti, Davide; Lubicz, Vittorio; Martinelli, Guido; Sanfilippo, Francesco; Simula, Silvano
2018-03-01
We present a lattice calculation of the Hadronic Vacuum Polarization (HVP) contribution of the strange and charm quarks to the anomalous magnetic moment of the muon including leading-order electromagnetic (e.m.) corrections. We employ the gauge configurations generated by the European Twisted Mass Collaboration (ETMC) with Nf = 2+1 + 1 dynamical quarks at three values of the lattice spacing (a ≃ 0.062,0.082,0.089 fm) with pion masses in the range Mπ ≃ 210 - 450 MeV. The strange and charm quark masses are tuned at their physical values. Neglecting discon-nected diagrams and after the extrapolations to the physical pion mass and to the continuum limit we obtain: aμs(αem2) = (53.1 ± 2.5 )×10-10, aμs(αem2) = (-0.018 ± 0.011)×10-10 and aμs(αem2) = (14.75±0.56)×10-10,aμs(αem2) = (-0.030±0.013)×10-10 for the strange and charm contributions, respectively.!
Leading isospin-breaking corrections to meson masses on the lattice
Giusti, Davide; Lubicz, Vittorio; Martinelli, Guido; Sanfilippo, Francesco; Simula, Silvano; Tantalo, Nazario; Tarantino, Cecilia
2018-03-01
We present a study of the isospin-breaking (IB) corrections to pseudoscalar (PS) meson masses using the gauge configurations produced by the ETM Collaboration with Nf = 2+1+1 dynamical quarks at three lattice spacings varying from 0.089 to 0.062 fm. Our method is based on a combined expansion of the path integral in powers of the small parameters (m⌢d-m⌢u)/ΛQCD and αem, where m⌢f is the renormalized quark mass and αem the renormalized fine structure constant. We obtain results for the pion, kaon and Dmeson mass splitting; for the Dashen's theorem violation parameters εγ(MM, 2 GeV), επ0 εK0(MS, 2 GeV) for the light quark masses (m⌢d-m⌢u)(MS¯,2 GeV),(m⌢u/m⌢d)(MS¯,2 GeV); for the flavour symmetry breaking parameters R(MS, 2 GeV) and Q(MS, 2 GeV) and for the strong IB effects on the kaon decay constants.
Up and Down Quark Masses and Corrections to Dashen's Theorem from Lattice QCD and Quenched QED.
Fodor, Z; Hoelbling, C; Krieg, S; Lellouch, L; Lippert, Th; Portelli, A; Sastre, A; Szabo, K K; Varnhorst, L
2016-08-19
In a previous Letter [Borsanyi et al., Phys. Rev. Lett. 111, 252001 (2013)] we determined the isospin mass splittings of the baryon octet from a lattice calculation based on N_{f}=2+1 QCD simulations to which QED effects have been added in a partially quenched setup. Using the same data we determine here the corrections to Dashen's theorem and the individual up and down quark masses. Our ensembles include 5 lattice spacings down to 0.054 fm, lattice sizes up to 6 fm, and average up-down quark masses all the way down to their physical value. For the parameter which quantifies violations to Dashen's theorem, we obtain ϵ=0.73(2)(5)(17), where the first error is statistical, the second is systematic, and the third is an estimate of the QED quenching error. For the light quark masses we obtain, m_{u}=2.27(6)(5)(4) and m_{d}=4.67(6)(5)(4) MeV in the modified minimal subtraction scheme at 2 GeV and the isospin breaking ratios m_{u}/m_{d}=0.485(11)(8)(14), R=38.2(1.1)(0.8)(1.4), and Q=23.4(0.4)(0.3)(0.4). Our results exclude the m_{u}=0 solution to the strong CP problem by more than 24 standard deviations.
International Nuclear Information System (INIS)
Deng Zhongguo
1989-01-01
The mass spectrometric determination of magnesium isotopic ratios by the use of uranyl nitrate added to magnesium samples to act as a binding agent is reported. Prebaking empty filaments and preheating filaments with deposited magnesium samples on its surface in a vacuum are employed to reduce the Na signal from the thenium-ribbon. Methods for correcting magnesium isotopic ratios for electron multiplier discrimination and mass fractionation are described in detail. The results of the determination of natural magnesium isotopic ratios are 25 Mg/ 24 Mg = 0.12660 (1±0.01%) and 26 Mg/ 24 Mg = 0.13938 (1±0.10%). The magnesium isotopic ratios of rich - 26 Mg-2 sample and rich- 25 Mg-1 sample are 24 Mg/ 26 Mg = 0.003463 (1±0.2%), 25 Mg/ 26 Mg = 0.001656 (±0.2%) and 24 Mg/ 25 Mg = 0.006716 (1±0.2%), 26 Mg/ 25 Mg = 0.007264 (1±0.2%) respectively
Zhang, Wei; Huang, Ting; Li, Hongmei; Dai, Xinhua; Quan, Can; He, Yajuan
2017-09-01
Quantitative Nuclear Magnetic Resonance (qNMR) is widely used to determine the purity of organic compounds. For the compounds with lower purity especially molecular weight more than 500, qNMR is at risk of error for the purity, because the impurity peaks are likely to be incompletely separated from the peak of major component. In this study, an offline ISRC-HPLC-qNMR (internal standard recovery correction - high performance liquid chromatography - qNMR) was developed to overcome this problem. It is accurate by excluding the influence of impurity; it is low-cost by using common mobile phase; and it extends the applicable scope of qNMR. In this method, a mix solution of the sample and an internal standard was separated by HPLC with common mobile phases, and only the eluents of the analyte and the internal standard were collected in the same tube. After evaporation and re-dissolution, it was determined by qNMR. A recovery correction factor was determined by comparison of the solutions before and after these procedures. After correction, the mass fraction of analyte was constant and it was accurate and precise, even though the sample loss varied during these procedures, or even in bad resolution of HPLC. Avermectin B 1 a with the purity of ~93% and the molecular weight of 873 was analyzed. Moreover, the homologues of avermectin B 1 a were determined based on the identification and quantitative analysis by tandem mass spectrometry and HPLC, and the results were consistent with the results of traditional mass balance method. The result showed that the method could be widely used for the organic compounds, and could further promote qNMR to become a primary method in the international metrological systems. Copyright © 2017 Elsevier B.V. All rights reserved.
Deformation and shell effects in nuclear mass formulas
International Nuclear Information System (INIS)
Barbero, César; Hirsch, Jorge G.; Mariano, Alejandro E.
2012-01-01
We analyze the ability of three different Liquid Drop Mass (LDM) formulas to describe nuclear masses for nuclei in various deformation regions. Separating the 2149 measured nuclear species into eight sets with similar quadrupole deformations, we show that the masses of prolate deformed nuclei are better described than those of spherical ones. In fact, the prolate deformed nuclei are fitted with an RMS smaller than 750 keV, while for spherical and semi-magic species the RMS is always larger than 2000 keV. These results are found to be independent of pairing. It is also shown that the macroscopic sector of the Duflo–Zuker (DZ) mass model reproduces shell effects, while most of the deformation dependence is lost and the RMS is larger than in any LDM. Adding to the LDM the microscopically motivated DZ master terms introduces the shell effects, allowing for a significant reduction in the RMS of the fit but still exhibiting a better description of prolate deformed nuclei. The inclusion of shell effects following the Interacting Boson Model's ideas produces similar results.
Deformation and shell effects in nuclear mass formulas
Energy Technology Data Exchange (ETDEWEB)
Barbero, Cesar [Departamento de Fisica, Universidad Nacional de La Plata, C.C. 67, 1900 La Plata (Argentina); Instituto de Fisica La Plata, CONICET, 1900 La Plata (Argentina); Hirsch, Jorge G., E-mail: hirsch@nucleares.unam.mx [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, 04510 Mexico D.F. (Mexico); Mariano, Alejandro E. [Departamento de Fisica, Universidad Nacional de La Plata, C.C. 67, 1900 La Plata (Argentina); Instituto de Fisica La Plata, CONICET, 1900 La Plata (Argentina)
2012-01-15
We analyze the ability of three different Liquid Drop Mass (LDM) formulas to describe nuclear masses for nuclei in various deformation regions. Separating the 2149 measured nuclear species into eight sets with similar quadrupole deformations, we show that the masses of prolate deformed nuclei are better described than those of spherical ones. In fact, the prolate deformed nuclei are fitted with an RMS smaller than 750 keV, while for spherical and semi-magic species the RMS is always larger than 2000 keV. These results are found to be independent of pairing. It is also shown that the macroscopic sector of the Duflo-Zuker (DZ) mass model reproduces shell effects, while most of the deformation dependence is lost and the RMS is larger than in any LDM. Adding to the LDM the microscopically motivated DZ master terms introduces the shell effects, allowing for a significant reduction in the RMS of the fit but still exhibiting a better description of prolate deformed nuclei. The inclusion of shell effects following the Interacting Boson Model's ideas produces similar results.
Coulomb corrections to nuclear scattering lengths and effective ranges for weakly bound systems
International Nuclear Information System (INIS)
Mur, V.D.; Popov, V.S.; Sergeev, A.V.
1996-01-01
A procedure is considered for extracting the purely nuclear scattering length as and effective range rs (which correspond to a strong-interaction potential Vs with disregarded Coulomb interaction) from the experimentally determined nuclear quantities acs and rcs, which are modified by Coulomb interaction. The Coulomb renormalization of as and rs is especially strong if the system under study involves a level with energy close to zero (on the nuclear scale). This applies to formulas that determine the Coulomb renormalization of the low-energy parameters of s scattering (l=0). Detailed numerical calculations are performed for coefficients appearing in the equations that determine Coulomb corrections for various models of the potential Vs(r). This makes it possible to draw qualitative conclusions that the dependence of Coulomb corrections on the form of the strong-interaction potential and, in particular, on its small-distance behavior. A considerable enhancement of Coulomb corrections to the effective range rs is found for potentials with a barrier
International Nuclear Information System (INIS)
Anon.
1993-01-01
This WRC Bulletin concentrates on the major failure mechanisms observed in nuclear power plant piping during the past three decades and on corrective actions taken to minimize or eliminate such failures. These corrective actions are applicable to both replacement piping and the next generation of light-water reactors. This WRC Bulletin was written with the objective of meeting a need for piping criteria in Advanced Light-Water Reactors, but there is application well beyond the LWR industry. This Volume, in particular, is equally applicable to current nuclear power plants, fossil-fueled power plants, and chemical plants including petrochemical. Implementation of the recommendations for mitigation of specific problems should minimize severe failures or cracking and provide substantial economic benefit. This volume uses a case history approach to high-light various failure mechanisms and the corrective actions used to resolve such failures. Particular attention is given to those mechanisms leading to severe piping failures, where severe denotes complete severance, large ''fishmouth'' failures, or long throughwall cracks releasing a minimum of 50 gpm. The major failure mechanisms causing severe failure are erosion-corrosion and vibrational fatigue. Stress corrosion cracking also has been a common problem in nuclear piping systems. In addition thermal fatigue due to mixing-tee and to thermal stratification also is discussed as is microbiologically-induced corrosion. Finally, water hammer, which represents the ultimate in internally-generated dynamic high-energy loads, is discussed
International Nuclear Information System (INIS)
Chanfray, G.; Aouissat, Z.; Schuck, P.; Norenberg, W.
1990-01-01
The most important part of the intermediate range nucleon-nucleon attraction is attributed to the exchange of non interacting as well as interaction two pions in the I = J = O channel. The corresponding 2π exchange potential, or part of it, is often simulated by a sigma-meson exchange with mass of about 600 MeV, which is then used as a basic input to nuclear matter calculation. This may give in particular a justification to the popular σ-ψ model. However a number of question remains concerning the microscopic nature of such an effective sigma meson. The point the authors want to emphasize in this paper concerns the possible modification of the sigma in the medium since they think that it is made out of pions whose propagations are strongly altered by the medium. However also the ρ-meson may undergo similar in medium corrections which possibly are related to recent experimental findings. The authors discuss, with a very simple model, the problem of pion propagation and pion-pion interaction in the medium and the occurrence of highly collective pion-delta modes (pionic branch, pisobar, quasi pion) in agreement with experimental data. They also should have some very important consequences on the dynamics of relativistic heavy collision. The authors address the very important question of the nuclear matter equation of state where collective pionic effects are included to reconstruct an effective sigma exchange whose mass and coupling constant are density dependent
Sensitivity studies for the main r process: nuclear masses
Directory of Open Access Journals (Sweden)
A. Aprahamian
2014-02-01
Full Text Available The site of the rapid neutron capture process (r process is one of the open challenges in all of physics today. The r process is thought to be responsible for the creation of more than half of all elements beyond iron. The scientific challenges to understanding the origin of the heavy elements beyond iron lie in both the uncertainties associated with astrophysical conditions that are needed to allow an r process to occur and a vast lack of knowledge about the properties of nuclei far from stability. One way is to disentangle the nuclear and astrophysical components of the question. On the nuclear physics side, there is great global competition to access and measure the most exotic nuclei that existing facilities can reach, while simultaneously building new, more powerful accelerators to make even more exotic nuclei. On the astrophysics side, various astrophysical scenarios for the production of the heaviest elements have been proposed but open questions remain. This paper reports on a sensitivity study of the r process to determine the most crucial nuclear masses to measure using an r-process simulation code, several mass models (FRDM, Duflo-Zuker, and HFB-21, and three potential astrophysical scenarios.
Evaluation of correction in shaping body mass women first adulthood with different personal features
Directory of Open Access Journals (Sweden)
S.A. Smaylova
2013-06-01
Full Text Available Assessed the effectiveness of training method of the "Shaping Classic" on the catabolic program correction of body weight the first mature age women with different personality characteristics. The study involved 20 women aged 26 - 30 years with a body mass index above average and high. Conducted anthropometric measurements. Used physiological tests, step test Prohorovtseva, engine test, psychodiagnostic methods. The efficiency of the program in reducing total body weight and body fat. The positive impact of the program on the functional state of the cardiovascular system and the musculoskeletal system is shown. Found that particular dispositions eating and self-esteem of women may reduce the level of impact of training. It is revealed that these features contribute to devaluing recommendations coach and weaken the motivation to train.
International Nuclear Information System (INIS)
Hegstrom, R.A.; Lhuillier, C.
1977-01-01
Starting from a classical covariant equation of motion for the spin of a particle moving in a homogeneous electromagnetic field (the Bargmann-Michel-Telegdi equation), we show that the ''relativistic mass'' correction to the electron spin magnetic moment, which has been obtained previously from relativistic quantum-mechanical treatments of the Zeeman effect, may be reinterpreted as the combination of three classical effects: (i) the difference in time scales in the electron rest frame vis-a-vis the lab frame, (ii) the Lorentz transformation of the magnetic field between the two frames, and (iii) the Thomas precession of the electron spin due to the acceleration of the electron produced by the magnetic field
Analysis on one underground nuclear waste repository rock mass in USA
International Nuclear Information System (INIS)
Ha Qiuling; Zhang Tiantian
2012-01-01
When analyzing the rock mass of a underground nuclear waste repository, the current studies are all based on the loading mechanical condition, and the unloading damage of rock mass is unconsidered. According to the different mechanical condition of actual engineering rock mass of loading and unloading, this paper implements a comprehensive analysis on the rock mass deformation of underground nuclear waste repository through the combination of present loading and unloading rock mass mechanics. It is found that the results of comprehensive analysis and actual measured data on the rock mass deformation of underground nuclear waste repository are basically the same, which provide supporting data for the underground nuclear waste repository. (authors)
New discovery: Quantization of atomic and nuclear rest mass differences
International Nuclear Information System (INIS)
Gareev, F. A.; Zhidkova, I. E.
2007-01-01
We come to the conclusion that all atomic models based on either the Newton equation and the Kepler laws, or the Maxwell equations, or the Schrodinger and Dirac equations are in reasonable agreement with experimental data. We can only suspect that these equations are grounded on the same fundamental principle(s) which is (are) not known or these equations can be transformed into each other. We proposed a new mechanism of LENR: cooperative processes in the whole system - nuclei + atoms + condensed matter - nuclear reactions in plasma - can occur at smaller threshold energies than the corresponding ones on free constituents. We were able to quantize [1] phenomenologically the first time the differences between atomic and nuclear rest masses by the formula: ΔΔ M = n 1 /n 2 x 0.0076294 (in MeV/c 2 ), n i =1,2,3,... Note that this quantization rule is justified for atoms and nuclei with different A, N and Z and the nuclei and atoms represent a coherent synchronized open systems - a complex of coupled oscillators (resonators). The cooperative resonance synchronization mechanisms are responsible for explanation of how the electron volt world can influence on the nuclear mega electron volt world. It means that we created new possibilities for inducing and controlling nuclear reactions by atomic processes grounded on the fundamental low of physics - conservation law of energy. The results of these research fields can provide new ecologically pure mobile sources of energy independent from oil, gas and coal, new substances, and technologies. For example, this discovery gives us a simple and cheep method for utilization of nuclear waste. References [1] F.A. Gareev, I.E. Zhidkova, E-print arXiv Nucl-th/0610002 2006
Energy Technology Data Exchange (ETDEWEB)
Kneesch, Torben
2010-12-15
We have calculated the single-inclusive production cross section of massive quarks in electron-positron-annihilation with next-to-leading order QCD corrections. With these results we have extracted fragmentation functions for the fragmentation from partons into D{sup 0}, D{sup +} and D{sup *} mesons, where we have used experimental data from the B factories Belle and CLEO and from the ALEPH and OPAL experiments at the LEP collider. In our analysis we have included the masses of c and b quarks and of the D mesons and tested the evolution of fragmentation functions with a global fit spanning the B factories' center-of-mass energy of {radical}(s)=10.5 GeV to LEP's run at the Z boson resonance at M{sub Z}. We have applied this fragmentation functions in deep inelastic scattering for comparisons with HERA data using parton cross sections from the literature available in program form. We have then modified this cross section to calculate predictions for deep inelastic two-photon-scattering. By applying the Weizsaecker-Williams spectrum on the real photon we have calculated predictions for LEP1, LEP2 and the future ILC experiments. For ILC we have also included a beamstrahlung spectrum. Finally we have calculated production cross sections for the planned e{gamma} mode of the ILC with the help of a Compton spectrum. (orig.)
Investigation of an orbital mass - the role of nuclear medicine
International Nuclear Information System (INIS)
Dunlop, R. V.
2009-01-01
Full text:A 35 year old male presented, suffering from night sweats, occipital and frontal headaches, blurred vision, nausea and a decrease in appetite. He underwent a CT and MRI scan, which identified a 2.2cm lesion in the left orbit in an intra-conal position. This was suspected to be a cavernous haemangioma, although other tumours, such as Schwannoma could not be ruled out. A nuclear medicine labelled red blood cell study was performed which included initial dynamic images and early statics and 120min delayed images. SPECT/CT was also performed at the later time. The characteristic blood pool mismatch of low early and high delayed concentration of red blood cells confirmed suspicions of a cavernous haemangioma, which, although comprised mainly of blood vessels, has slow flow. Hence there is considerable delay before maximum activity is reached. The lesion was surgically removed. Histology reports confirmed the nuclear medicine results. Nuclear Medicine has the potential to play a significant role in the preoperative diagnosis of an orbital mass.
International Nuclear Information System (INIS)
Boros, C.
1999-01-01
Recent measurement of the structure function F 2 υ in neutrino deep inelastic scattering allows us to compare structure functions measured in neutrino and charged lepton scattering for the first time with reasonable precision. The comparison between neutrino and muon structure functions made by the CCFR Collaboration indicates that there is a discrepancy between these structure functions at small Bjorken x values. In this talk I examine two effects which might account for this experimental discrepancy: nuclear shadowing corrections for neutrinos and contributions from strange and anti-strange quarks. Copyright (1999) World Scientific Publishing Co. Pte. Ltd
Correction of Hypothyroidism Leads to Change in Lean Body Mass without Altering Insulin Resistance.
Sirigiri, Sangeetha; Vaikkakara, Suresh; Sachan, Alok; Srinivasarao, P V L N; Epuri, Sunil; Anantarapu, Sailaja; Mukka, Arun; Chokkapu, Srinivasa Rao; Venkatanarasu, Ashok; Poojari, Ravi
2016-12-01
Hypothyroidism is associated with insulin resistance, dyslipidemia, and abnormal body composition. This study assessed changes in body composition and insulin resistance after thyroxine (T 4 ) replacement in overt hypothyroidism. In this prospective longitudinal study carried out in a tertiary care center, adult nondiabetic patients with overt hypothyroidism were rendered euthyroid on T 4 . Anthropometry including skinfold thickness (SFT) at the triceps and subscapularis was recorded. Patients underwent testing for fasting plasma glucose, creatinine, serum insulin, T 4 , thyrotropin (TSH) and body composition analysis by dual-energy X-ray absorptiometry (DEXA) both before and at 2 months after restoration to the euthyroid state. Twenty-seven patients (20 female and 7 male) aged 35.3 ± 11.0 years (min-max: 17-59 years) with overt hypothyroidism were recruited. Serum T 4 at the time of recruitment was 48.9 ± 24.6 nmol/l (normal range = 64.4-142 nmol/l). All patients had TSH ≥50 µIU/l. Following treatment, there was a mean body weight reduction of 1.7 kg (p = 0.01). Waist circumference as well as triceps and subscapularis SFT decreased significantly (p change in fat mass (FM), percentage of fat (%FM) or bone mineral content in any of the specified regions or in the body as a whole. In contrast, mean lean body mass (LBM) decreased significantly by 0.8 kg (p resistance and level of glycemia were not affected by treatment with T 4 . LBM decreases significantly without affecting FM after correction of hypothyroidism. Insulin resistance was not influenced by T 4 treatment.
Finite temperature corrections to tachyon mass in intersecting D-branes
International Nuclear Information System (INIS)
Sethi, Varun; Chowdhury, Sudipto Paul; Sarkar, Swarnendu
2017-01-01
We continue with the analysis of finite temperature corrections to the Tachyon mass in intersecting branes which was initiated in https://www.doi.org/10.1007/JHEP09(2014)063. In this paper we extend the computation to the case of intersecting D3 branes by considering a setup of two intersecting branes in flat-space background. A holographic model dual to BCS superconductor consisting of intersecting D8 branes in D4 brane background was proposed in https://www.doi.org/10.1016/j.nuclphysb.2011.07.011. The background considered here is a simplified configuration of this dual model. We compute the one-loop Tachyon amplitude in the Yang-Mills approximation and show that the result is finite. Analyzing the amplitudes further we numerically compute the transition temperature at which the Tachyon becomes massless. The analytic expressions for the one-loop amplitudes obtained here reduce to those for intersecting D1 branes obtained in https://www.doi.org/10.1007/JHEP09(2014)063 as well as those for intersecting D2 branes.
Finite temperature corrections to tachyon mass in intersecting D-branes
Energy Technology Data Exchange (ETDEWEB)
Sethi, Varun [Department of Physics and Astrophysics, University of Delhi,Delhi 110007 (India); Chowdhury, Sudipto Paul [Institute of Physics, Sachivalaya Marg,Bhubaneswar 751005 (India); Sarkar, Swarnendu [Department of Physics and Astrophysics, University of Delhi,Delhi 110007 (India)
2017-04-19
We continue with the analysis of finite temperature corrections to the Tachyon mass in intersecting branes which was initiated in https://www.doi.org/10.1007/JHEP09(2014)063. In this paper we extend the computation to the case of intersecting D3 branes by considering a setup of two intersecting branes in flat-space background. A holographic model dual to BCS superconductor consisting of intersecting D8 branes in D4 brane background was proposed in https://www.doi.org/10.1016/j.nuclphysb.2011.07.011. The background considered here is a simplified configuration of this dual model. We compute the one-loop Tachyon amplitude in the Yang-Mills approximation and show that the result is finite. Analyzing the amplitudes further we numerically compute the transition temperature at which the Tachyon becomes massless. The analytic expressions for the one-loop amplitudes obtained here reduce to those for intersecting D1 branes obtained in https://www.doi.org/10.1007/JHEP09(2014)063 as well as those for intersecting D2 branes.
On Gluonic Corrections to the Mass Spectrum in a Relativistic Charmonium Model
Hitoshi, ITO; Department of Physics, Faculty of Science and Technology Kinki University
1984-01-01
It is shown that the gluonic correction in the innermost region is abnormally large in the ^1S_0 State and a cutoff parameter which suppresses this correction. should be introduced. The retardation effect is estimated under this restriction on the gluonic correction. The correction due to the pair creation is shown to be small except for the ^1S_0 and ^3P_0 states.
A Simple Correlation for Neutron Capture Rates from Nuclear Masses
Energy Technology Data Exchange (ETDEWEB)
Couture, Aaron Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2018-01-30
Recent studies of neutron capture performed at LANL have revealed a previously unrecognized connection between nuclear masses and the average neutron capture cross section. A team of three scientists from Los Alamos (P-27), Yale Univ., and Istanbul Univ. (Turkey) recently discovered this connection and have published their results as a Rapid Communication in Physical Review C. Neutron capture is a reaction in which a free neutron is absorbed by the nucleus, keeping the element unchanged, but changing isotopes. This reaction is typically exothermic. As a result, the reaction can proceed even when many other reaction channels are closed. In an astrophysical environment, this means that neutron capture is the primary mechanism by which all of the elements with atomic number greater than nickel are produced is neutron capture.
Prediction of heat and mass transfer in innovative nuclear reactors
International Nuclear Information System (INIS)
Ambrosini, W.; Forgione, N.; Manfredini, A.; Oriolo, F.
2000-01-01
This paper proposes a short review of the different forms adopted to express the analogy between heat and mass transfer for application in correlating data from condensation and evaporation experiments. In particular, the assumptions at the basis of the various forms presented by classical textbooks as well as recent research work are qualitatively discussed, proposing a unified treatment of the different models. On this background, the results of the application of one of the considered forms of the analogy to a problem having relevance for nuclear reactor safety are then discussed. The work performed in this frame is related to condensation on finned tube heat exchangers, proposed as key components in passive containment cooling systems adopted in some innovative reactor concepts. The application of the model to the experimental dana also allowed to obtain interesting information about the effect of different parameters on the cooling capabilities of this compact heat exchangers. (author)
Energy Technology Data Exchange (ETDEWEB)
Lopez-Pavon, J. [SISSA and INFN - sezione di Trieste, via Bonomea 265, 34136 Trieste (Italy); Molinaro, E. [CP-Origins and Danish Institute for Advanced Study, University of Southern Denmark,Campusvej 55, DK-5230 Odense M (Denmark); Petcov, S.T. [SISSA and INFN - sezione di Trieste, via Bonomea 265, 34136 Trieste (Italy); Kavli IPMU (WPI), University of Tokyo, 5-1-5 Kashiwanoha, 277-8583 Kashiwa (Japan)
2015-11-05
We perform a detailed analysis of the one-loop corrections to the light neutrino mass matrix within low scale type I seesaw extensions of the Standard Model and their implications in experimental searches for neutrinoless double beta decay. We show that a sizable contribution to the effective Majorana neutrino mass from the exchange of heavy Majorana neutrinos is always possible, provided one requires a fine-tuned cancellation between the tree-level and one-loop contribution to the light neutrino masses. We quantify the level of fine-tuning as a function of the seesaw parameters and introduce a generalisation of the Casas-Ibarra parametrization of the neutrino Yukawa matrix, which easily allows to include the one-loop corrections to the light neutrino masses.
Nuclear technology: katulong sa pag-unlad ng masa [support for the progress of the masses
International Nuclear Information System (INIS)
1999-01-01
The topics discussed during the convention is the usefulness of nuclear science and technology in national development and to promote the beneficial uses of nuclear science and technology to support for the progress of the masses
Accelerator Mass Spectrometry with 15 UD pelletron at the Nuclear Science Centre, New Delhi
International Nuclear Information System (INIS)
Datta, S.K.
1997-01-01
The 15 UD Pelletron machine is widely used to carry on investigations in a variety of disciplines like nuclear physics, materials science, radiobiology etc. Accelerator Mass Spectrometry studies with 15 UD pelletron machine at Nuclear Science Centre are elaborated
Radiocarbon mass balance for a Magnox nuclear power station
International Nuclear Information System (INIS)
Metcalfe, M.P.; Mills, R.W.
2015-01-01
Highlights: • First comprehensive assessment of C-14 arisings in a Magnox nuclear power station. • C-14 production in graphite and coolant gas quantified by activation modelling. • Principal C-14 production pathway is via C-13 with a small contribution from N-14. • C-14 mass balance model provides a basis for analyses on other reactors. - Abstract: Nuclear power generation in the United Kingdom is based principally on graphite-moderated gas-cooled reactors. The mass of irradiated graphite associated with these reactors, including material from associated experimental, prototype and plutonium production reactors, exceeds 96,000 tonnes. One of the principal long-lived radionuclides produced during graphite irradiation is radiocarbon (C-14). Its potential as a hazard must be taken into account in decommissioning and graphite waste management strategies. While C-14 production processes are well-understood, radionuclide distributions and concentrations need to be characterised. A common misconception is that generic statements can be made about C-14 precursors and their location. In fact, the composition of the original manufactured material, the chemical environment of the graphite during service and its irradiation history will all influence C-14 levels. The analysis presented here provides the first assessment of the principal C-14 activation pathways for a UK Magnox reactor. Activation modelling has been used to predict C-14 production rates in both the graphite core and the carbon dioxide coolant over a selected period of operation and the results compared with monitored site C-14 discharges. Principal activation routes have been identified, which should inform future graphite waste management strategies relating to radiocarbon
International Nuclear Information System (INIS)
Barik, N.; Dash, B.K.; Das, M.
1985-01-01
The static properties, such as magnetic moment, charge radius, and axial-vector coupling constants, of the quark core of baryons in the nucleon octet have been studied in an independent-quark model based on the Dirac equation with equally mixed scalar-vector potential in harmonic form in the current quark mass limit. The results obtained with the corrections due to center-of-mass motion are in reasonable agreement with experimental values
Radiocarbon Mass Balance for a Magnox Nuclear Power Station
International Nuclear Information System (INIS)
Metcalfe, M.P.; Mills, R.W.
2016-01-01
Nuclear power generation in the United Kingdom is based principally on graphite-moderated gas-cooled reactors. The mass of irradiated graphite associated with these reactors, including material from associated experimental, prototype and production reactors, exceeds 96,000 tonnes. One of the principal long-lived radionuclides produced during graphite irradiation is radiocarbon (C-14), which has a half-life of 5730 ± 40 years. Decommissioning and graphite waste management strategies must take account of this radionuclide. In order to identify appropriate options for addressing the potential hazard of C-14, it is important that the production processes are understood and the distributions and concentrations of C-14 are characterised. In fact, C-14 precursors and their activation processes are well-known. However, there is ongoing debate over the relative importance of different C-14 precursors, which will determine the location of C-14 within graphite components and hence its mobility/response to treatment. A generally held misconception concerning C-14 in irradiated graphite is that generic statements can be made about its precursors and their location. C-14 location and activities will depend upon the composition of the original manufactured graphite (raw materials, impurities), the chemical environment of the graphite during service and the irradiation history of the graphite. So, while there may be some similarities across, for example, carbon dioxide cooled graphite moderated designs (Magnox, AGR, UNGG), any informed assessment of a core’s C-14 inventory would require more-precise characterisation. The analysis presented here focuses on a UK Magnox reactor core, Reactor 1 at Wylfa Nuclear Power Station. The objective of the analysis is to present a full C-14 mass balance over a selected period of operation for which there are accurate C-14 discharge records. The analysis presented here provides the first assessment of the principal C-14 activation pathways
One loop corrections to the lightest Higgs mass in the minimal η model with a heavy Z'
International Nuclear Information System (INIS)
Comelli, D.
1992-06-01
We have evaluated the one loop correction to the bound on the lightest Higgs mass valid in the minimal, E 6 based, supersymmetric η model in the presence of a 'heavy' Z', M z' ≥1 TeV. The dominant contribution from the fermion sfermion sector increases the 108 GeV tree level value by an amount that depends on the top mass in a way that is largely reminescent of minimal SUSY models. For M t ≤150 GeV, Msub(t tilde)=1 TeV, the 'light' Higgs mass is always ≤130 GeV. (orig.)
International Nuclear Information System (INIS)
Kim, Y.P.
1982-01-01
The sensational Three Mile Island Nuclear Power Plant Accident of 1979 raised many policy problems. Since the TMI accident, many authorities in the nation, including the President's Commission on TMI, Congress, GAO, as well as NRC, have researched lessons and recommended various corrective measures for the improvement of nuclear regulatory policy. As an effort to translate the recommendations into effective actions, the NRC developed the TMI Action Plan. How sound are these corrective actions. The NRC approach to the TMI Action Plan is justifiable to the extent that decisions were reached by procedures to reduce the effects of judgmental bias. Major findings from the NRC's effort to justify the corrective actions include: (A) The deficiencies and errors in the operations at the Three Mile Island Plant were not defined through a process of comprehensive analysis. (B) Instead, problems were identified pragmatically and segmentally, through empirical investigations. These problems tended to take one of two forms - determinate problems subject to regulatory correction on the basis of available causal knowledge, and indeterminate problems solved by interim rules plus continuing study. The information to justify the solution was adjusted to the problem characteristics. (C) Finally, uncertainty in the determinate problems was resolved by seeking more causal information, while efforts to resolve indeterminate problems relied upon collective judgment and a consensus rule governing decisions about interim resolutions
Partial volume effect correction in nuclear medicine: assessment with a mathematical phantom
International Nuclear Information System (INIS)
Silva, Murilo Collete da; Pozzo, Lorena
2009-01-01
Objective: assessment of Van Cittert partial volume effect correction method in nuclear medicine images, with a mathematical phantom. Material and method: we simulated an image of four circular sources of different diameters and intensity of 255 per pixel. The iterative algorithm was applied with 20 iterations and α = 1. We obtained the maximum and average counts on the entire image and in regions of interest placed on each of the sources. We also extracted count profiles plotted along the diameter of each of the sources. Results: the local convergence depends on the size of the source studied: the smaller the source, the greater the number of iterations required. It also depends on the information extracted: the use of average counts provides more homogeneous results than the maximum count. There is a significant improvement in image contrast. Conclusion: this study showed the possibility of qualitative and quantitative improvement in applying the bidimensional iterative Van Cittert method to images of simple geometry. (author)
Correction of the kinetic blur and representation of heart dynamics in nuclear imagery
International Nuclear Information System (INIS)
Ignaszewski, A.; Vaillant, D.; Sabatier, J.P.; Fernandez, Y.
1975-01-01
In heart cavity studies the simplicity and harmlessness nuclear imagery are great advantages, but it is necessary to improve on the data obtainable by this technique. The usual image is faulty, owing to the presence of a kinetic softness, and deficient because it fails to account for the mobility of the walls. An attempt was made to correct the kinetic softness on an image and to reconstitute the film of a heart cycle, an aim achieved by combining a computer with the camera. The examination conditions generally adopted include storage of all data and a reconstitution of the entire cycle is programmed taking a multiple time unit of 20ms; this supplies a sequence of images which when observed in succession resembles the heat contractility film [fr
Jones, S. P.; Kerner, M.; Luisoni, G.
2018-04-01
We present the next-to-leading-order QCD corrections to the production of a Higgs boson in association with one jet at the LHC including the full top-quark mass dependence. The mass of the bottom quark is neglected. The two-loop integrals appearing in the virtual contribution are calculated numerically using the method of sector decomposition. We study the Higgs boson transverse momentum distribution, focusing on the high pt ,H region, where the top-quark loop is resolved. We find that the next-to-leading-order QCD corrections are large but that the ratio of the next-to-leading-order to leading-order result is similar to that obtained by computing in the limit of large top-quark mass.
Collon, P.; Bauder, W.; Bowers, M.; Lu, W.; Ostdiek, K.; Robertson, D.
The Accelerator Mass Spectrometry (AMS) program at the Nuclear Science Laboratory of the University of Notre Dame is focused on measurements related to galactic radioactivity and to nucleosynthesis of main stellar burning as well as the production of so called Short-Lived Radionuclides (SLRs) in the Early Solar System (ESS). The research program is based around the 11MV FN tandem accelerator and the use of the gas-filled magnet technique for isobar separation. Using a technique that evolved from radiocarbon dating, this paper presents a number of research programs that rely on the use of an 11MV tandem accelerator at the center of the AMS program.
Publisher Correction: Cluster richness-mass calibration with cosmic microwave background lensing
Geach, James E.; Peacock, John A.
2018-03-01
Owing to a technical error, the `Additional information' section of the originally published PDF version of this Letter incorrectly gave J.A.P. as the corresponding author; it should have read J.E.G. This has now been corrected. The HTML version is correct.
Energy Technology Data Exchange (ETDEWEB)
Antoni, R.; Passard, C.; Perot, B.; Batifol, M.; Vandamme, J.C. [CEA, DEN, Cadarache, Nuclear Measurement Laboratory, F-13108 St Paul-lez-Durance, (France); Grassi, G. [AREVA NC, 1 place Jean-Millier, 92084 Paris-La-Defense cedex (France)
2015-07-01
The fissile mass in radioactive waste drums filled with compacted metallic residues (spent fuel hulls and nozzles) produced at AREVA La Hague reprocessing plant is measured by neutron interrogation with the Differential Die-away measurement Technique (DDT. In the next years, old hulls and nozzles mixed with Ion-Exchange Resins will be measured. The ion-exchange resins increase neutron moderation in the matrix, compared to the waste measured in the current process. In this context, the Nuclear Measurement Laboratory (NML) of CEA Cadarache has studied a matrix effect correction method, based on a drum monitor ({sup 3}He proportional counter inside the measurement cavity). A previous study performed with the NML R and D measurement cell PROMETHEE 6 has shown the feasibility of method, and the capability of MCNP simulations to correctly reproduce experimental data and to assess the performances of the proposed correction. A next step of the study has focused on the performance assessment of the method on the industrial station using numerical simulation. A correlation between the prompt calibration coefficient of the {sup 239}Pu signal and the drum monitor signal was established using the MCNPX computer code and a fractional factorial experimental design composed of matrix parameters representative of the variation range of historical waste. Calculations have showed that the method allows the assay of the fissile mass with an uncertainty within a factor of 2, while the matrix effect without correction ranges on 2 decades. In this paper, we present and discuss the first experimental tests on the industrial ACC measurement system. A calculation vs. experiment benchmark has been achieved by performing dedicated calibration measurement with a representative drum and {sup 235}U samples. The preliminary comparison between calculation and experiment shows a satisfactory agreement for the drum monitor. The final objective of this work is to confirm the reliability of the
International Nuclear Information System (INIS)
Antoni, R.; Passard, C.; Perot, B.; Batifol, M.; Vandamme, J.C.; Grassi, G.
2015-01-01
The fissile mass in radioactive waste drums filled with compacted metallic residues (spent fuel hulls and nozzles) produced at AREVA La Hague reprocessing plant is measured by neutron interrogation with the Differential Die-away measurement Technique (DDT. In the next years, old hulls and nozzles mixed with Ion-Exchange Resins will be measured. The ion-exchange resins increase neutron moderation in the matrix, compared to the waste measured in the current process. In this context, the Nuclear Measurement Laboratory (NML) of CEA Cadarache has studied a matrix effect correction method, based on a drum monitor ( 3 He proportional counter inside the measurement cavity). A previous study performed with the NML R and D measurement cell PROMETHEE 6 has shown the feasibility of method, and the capability of MCNP simulations to correctly reproduce experimental data and to assess the performances of the proposed correction. A next step of the study has focused on the performance assessment of the method on the industrial station using numerical simulation. A correlation between the prompt calibration coefficient of the 239 Pu signal and the drum monitor signal was established using the MCNPX computer code and a fractional factorial experimental design composed of matrix parameters representative of the variation range of historical waste. Calculations have showed that the method allows the assay of the fissile mass with an uncertainty within a factor of 2, while the matrix effect without correction ranges on 2 decades. In this paper, we present and discuss the first experimental tests on the industrial ACC measurement system. A calculation vs. experiment benchmark has been achieved by performing dedicated calibration measurement with a representative drum and 235 U samples. The preliminary comparison between calculation and experiment shows a satisfactory agreement for the drum monitor. The final objective of this work is to confirm the reliability of the modeling approach
Characteristic relation for the mass and energy distribution of the nuclear fission products
International Nuclear Information System (INIS)
Alexandru, G.
1977-01-01
The dispersion relation for nuclear fission is written in the two part fragmentation approach which allows to obtain the characteristic relation for the mass and energy distribution of the nuclear fission products. One explains the resonance approximation in the mass distribution of the fission products taking into account the high order resonances too. (author)
Nuclear fuel, mass balances, conversion ratio, doubling time, and uncertainty
International Nuclear Information System (INIS)
Vondy, D.R.
1976-11-01
Information on the performance aspects of nuclear power plants is presented concerning conversion ratio, criticality, primitive economic analysis, stable breeder-converter industry, doubling time, breeder industry economic benefit, defining nuclear fuel, recommendations, and uncertainty
Energy Technology Data Exchange (ETDEWEB)
Mamyrin, B.A.; Aruev, N.N.; Alekseenko, S.A.
1983-06-01
In connection with the revision of the table values of the atomic masses and the forthcoming coordination of the values of the fundamental physical constants, the result of measurement of the proton magnetic moment in nuclear Magnetons obtained in 1971 is re-examined by taking into account recent data. With the atomic masses recognized in 1982 the proton magnetic moment expressed in nuclear magnetons without a correction for diamagnetic screening of the proton in a water molecule is found to be ..mu..sub(p)'/..mu..sub(n)=2.7927729+-0.0000012 (4.3x10/sup -5/%).
Asgari, Afrouz; Ashoor, Mansour; Sohrabpour, Mostafa; Shokrani, Parvaneh; Rezaei, Ali
2015-05-01
Improving signal to noise ratio (SNR) and qualified images by the various methods is very important for detecting the abnormalities at the body organs. Scatter and attenuation of photons by the organs lead to errors in radiopharmaceutical estimation as well as degradation of images. The choice of suitable energy window and the radionuclide have a key role in nuclear medicine which appearing the lowest scatter fraction as well as having a nearly constant linear attenuation coefficient as a function of phantom thickness. The energy windows of symmetrical window (SW), asymmetric window (ASW), high window (WH) and low window (WL) using Tc-99m and Sm-153 radionuclide with solid water slab phantom (RW3) and Teflon bone phantoms have been compared, and Matlab software and Monte Carlo N-Particle (MCNP4C) code were modified to simulate these methods and obtaining the amounts of FWHM and full width at tenth maximum (FWTM) using line spread functions (LSFs). The experimental data were obtained from the Orbiter Scintron gamma camera. Based on the results of the simulation as well as experimental work, the performance of WH and ASW display of the results, lowest scatter fraction as well as constant linear attenuation coefficient as a function of phantom thickness. WH and ASW were optimal windows in nuclear medicine imaging for Tc-99m in RW3 phantom and Sm-153 in Teflon bone phantom. Attenuation correction was done for WH and ASW optimal windows and for these radionuclides using filtered back projection algorithm. Results of simulation and experimental show that very good agreement between the set of experimental with simulation as well as theoretical values with simulation data were obtained which was nominally less than 7.07 % for Tc-99m and less than 8.00 % for Sm-153. Corrected counts were not affected by the thickness of scattering material. The Simulated results of Line Spread Function (LSF) for Sm-153 and Tc-99m in phantom based on four windows and TEW method were
Recent status of the studies of nuclear masses and {beta}-decay
Energy Technology Data Exchange (ETDEWEB)
Yamada, Masami [Waseda Univ., Tokyo (Japan). Advanced Research Center for Science and Engineering
1996-05-01
The recent status of the above studies was explained, especially, nuclear masses were described from the aspect of probability theory and that of {beta}-decay suggested that the first forbidden transition was hindered between the ground states. We have to study various systematics in order to know the mass surface, Way-Yamada-Matumoto type systematics is better to check the experimental nuclear masses. The gross theory is very useful to understand the general aspect of {beta}-decay. The understanding method of mass surface, systematic check of mass and hindrance of the first forbidden transition at rank 1 were explained. (S.Y.)
Recent status of the studies of nuclear masses and β-decay
International Nuclear Information System (INIS)
Yamada, Masami
1996-01-01
The recent status of the above studies was explained, especially, nuclear masses were described from the aspect of probability theory and that of β-decay suggested that the first forbidden transition was hindered between the ground states. We have to study various systematics in order to know the mass surface, Way-Yamada-Matumoto type systematics is better to check the experimental nuclear masses. The gross theory is very useful to understand the general aspect of β-decay. The understanding method of mass surface, systematic check of mass and hindrance of the first forbidden transition at rank 1 were explained. (S.Y.)
Extending and refining the nuclear mass surface with ISOLTRAP and MISTRAL
Lunney, M D
2000-01-01
Through the nuclear binding energy the atomic mass gives us important information about nuclear structure. Viewing the ensemble of mass data over the nuclear chart, we can examine the hills and valleys that form this surface and make hypotheses about the effects of certain nuclear configurations. To unveil these effects, mass measurements of very high precision (10$^{-6}$) are required. Two experiments at ISOLDE pursue this effort of nuclear cartography the tandem Penning trap spectrometer ISOLTRAP and the radiofrequency transmission spectrometer MISTRAL. Between them, the masses of almost 150 nuclides have been measured from stable isotopes to those with half-lives as short as 30 ms. Both experiments rely on good optical properties of a low energy ion beam and are thus well suited to the ISOLDE facility. (30 refs).
The mass media and nuclear energy in the US
International Nuclear Information System (INIS)
Roche, C.
1994-01-01
The role of the US media in informing the public about benefits of nuclear industry is discussed. Usually the media in USA is biased against nuclear energy and works on the side of anti-nuclear groups. The tendency of reporters to mistrust government and industry experts, and to trust 'environmental groups' poses a particular problem for the US nuclear industry. One of the challenges of nuclear industry is to convince the media that anti-nuclear groups are not acting in the public interest, but in self-interest too. The scientists who communicate with the media must help reporters to understand technology, but to do that, they must understand reporter's needs. Those include a quick response to requests for information, spokespersons who speak clearly and understandably, in human terms, and candor and honesty in all of the information they provide. (I.P.)
A correction technique for the dispersive effects of mass lumping for transport problems
Guermond, Jean-Luc; Pasquetti, Richard
2013-01-01
This paper addresses the well-known dispersion effect that mass lumping induces when solving transport-like equations. A simple anti-dispersion technique based on the lumped mass matrix is proposed. The method does not require any non-trivial matrix
Fouquet, Thierry N. J.; Cody, Robert B.; Ozeki, Yuka; Kitagawa, Shinya; Ohtani, Hajime; Sato, Hiroaki
2018-05-01
The Kendrick mass defect (KMD) analysis of multiply charged polymeric distributions has recently revealed a surprising isotopic split in their KMD plots—namely a 1/z difference between KMDs of isotopes of an oligomer at charge state z. Relying on the KMD analysis of actual and simulated distributions of poly(ethylene oxide) (PEO), the isotopic split is mathematically accounted for and found to go with an isotopic misalignment in certain cases. It is demonstrated that the divisibility (resp. indivisibility) of the nominal mass of the repeating unit (R) by z is the condition for homolog ions to line up horizontally (resp. misaligned obliquely) in a KMD plot. Computing KMDs using a fractional base unit R/z eventually corrects the misalignments for the associated charge state while using the least common multiple of all the charge states as the divisor realigns all the points at once. The isotopic split itself can be removed by using either a new charge-dependent KMD plot compatible with any fractional base unit or the remainders of KM (RKM) recently developed for low-resolution data all found to be linked in a unified theory. These original applications of the fractional base units and the RKM plots are of importance theoretically to satisfy the basics of a mass defect analysis and practically for a correct data handling of single stage and tandem mass spectra of multiply charged homo- and copolymers.
Quark mass corrections to the perturbative thrust and its effect on the ...
Indian Academy of Sciences (India)
atic approach for handling power corrections using perturbation theory. ... The numerator of the above is given up to З(αs) and to З(ξ) by (σ0 = (4πα2/s)e2 i is the .... MARK II. AMY. ALEPH. DELPHI. OPAL. Massless formula. Massive formula ... We can also estimate the theoretical uncertainties on these quantities by vary-.
Energy Technology Data Exchange (ETDEWEB)
Dunham, Michael M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS 78, Cambridge, MA 02138 (United States); Arce, Héctor G. [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520 (United States); Mardones, Diego [Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile); Lee, Jeong-Eun [Department of Astronomy and Space Science, Kyung Hee University, Yongin, Gyeonggi 446-701 (Korea, Republic of); Matthews, Brenda C. [National Research Council of Canada, Herzberg Astronomy and Astrophysics, 5071 W. Saanich Road, Victoria, BC V9E 2E7 (Canada); Stutz, Amelia M. [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117, Heidelberg (Germany); Williams, Jonathan P., E-mail: mdunham@cfa.harvard.edu [Institute for Astronomy, University of Hawaii, Honolulu, HI 96822 (United States)
2014-03-01
We present a survey of 28 molecular outflows driven by low-mass protostars, all of which are sufficiently isolated spatially and/or kinematically to fully separate into individual outflows. Using a combination of new and archival data from several single-dish telescopes, 17 outflows are mapped in {sup 12}CO (2-1) and 17 are mapped in {sup 12}CO (3-2), with 6 mapped in both transitions. For each outflow, we calculate and tabulate the mass (M {sub flow}), momentum (P {sub flow}), kinetic energy (E {sub flow}), mechanical luminosity (L {sub flow}), and force (F {sub flow}) assuming optically thin emission in LTE at an excitation temperature, T {sub ex}, of 50 K. We show that all of the calculated properties are underestimated when calculated under these assumptions. Taken together, the effects of opacity, outflow emission at low velocities confused with ambient cloud emission, and emission below the sensitivities of the observations increase outflow masses and dynamical properties by an order of magnitude, on average, and factors of 50-90 in the most extreme cases. Different (and non-uniform) excitation temperatures, inclination effects, and dissociation of molecular gas will all work to further increase outflow properties. Molecular outflows are thus almost certainly more massive and energetic than commonly reported. Additionally, outflow properties are lower, on average, by almost an order of magnitude when calculated from the {sup 12}CO (3-2) maps compared to the {sup 12}CO (2-1) maps, even after accounting for different opacities, map sensitivities, and possible excitation temperature variations. It has recently been argued in the literature that the {sup 12}CO (3-2) line is subthermally excited in outflows, and our results support this finding.
A correction technique for the dispersive effects of mass lumping for transport problems
Guermond, Jean-Luc
2013-01-01
This paper addresses the well-known dispersion effect that mass lumping induces when solving transport-like equations. A simple anti-dispersion technique based on the lumped mass matrix is proposed. The method does not require any non-trivial matrix inversion and has the same anti-dispersive effects as the consistent mass matrix. A novel quasi-lumping technique for P2 finite elements is introduced. Higher-order extensions of the method are also discussed. © 2012 Elsevier B.V.
International Nuclear Information System (INIS)
Anon.
1981-01-01
The standard covers analytical procedures to determine compliance of nuclear-grade uranyl nitrate solution to specifications. The following methods are described in detail: uranium by ferrous sulfate reduction-potassium dichromate titrimetry and by ignition gravimetry; specific gravity by pycnometry; free acid by oxalate complexation; thorium by the Arsenazo(III) (photometric) method; chromium by the diphenylcarbazide (photometric) method; molybdenum by the thiocyanate (photometric) method; halogens separation by steam distillation; fluorine by specific ion electrode; halogen distillate analysis: chloride, bromide and iodide by amperometric microtitrimetry; bromine by the fluorescein (photometric) method; sulfate sulfur by (photometric) turbidimetry; phosphorus by the molybdenum blue (photometric) method; silicon by the molybdenum blue (photometric) method; carbon by persulfate oxidation-acid titrimetry; nonvolatile impurities by spectrography; volatile impurities by rotating-disk spark spectrography; boron by emission spectrography; impurity elements by spark source mass spectrography; isotopic composition by multiple filament surface-ionization mass spectrometry; uranium-232 by alpha spectrometry; total alpha activity by direct alpha counting; fission product activity by beta and gamma counting; entrained organic matter by infrared spectrophotometry
Finite-lattice-spacing corrections to masses and g factors on a lattice
International Nuclear Information System (INIS)
Roskies, R.; Wu, J.C.
1986-01-01
We suggest an alternative method for extracting masses and g factors from lattice calculations. Our method takes account of more of the infrared and ultraviolet lattice effects. It leads to more reasonable results in simulations of QED on a lattice
International Nuclear Information System (INIS)
Scott, Nicholas; Graham, Alister W.
2013-01-01
We investigate whether or not nuclear star clusters and supermassive black holes (SMBHs) follow a common set of mass scaling relations with their host galaxy's properties, and hence can be considered to form a single class of central massive object (CMO). We have compiled a large sample of galaxies with measured nuclear star cluster masses and host galaxy properties from the literature and fit log-linear scaling relations. We find that nuclear star cluster mass, M NC , correlates most tightly with the host galaxy's velocity dispersion: log M NC = (2.11 ± 0.31)log (σ/54) + (6.63 ± 0.09), but has a slope dramatically shallower than the relation defined by SMBHs. We find that the nuclear star cluster mass relations involving host galaxy (and spheroid) luminosity and stellar and dynamical mass, intercept with but are in general shallower than the corresponding black hole scaling relations. In particular, M NC ∝M 0.55±0.15 Gal,dyn ; the nuclear cluster mass is not a constant fraction of its host galaxy or spheroid mass. We conclude that nuclear stellar clusters and SMBHs do not form a single family of CMOs.
Neutron-Proton Mass Difference in Nuclear Matter and in Finite Nuclei and the Nolen-Schiffer Anomaly
Directory of Open Access Journals (Sweden)
Yakhshiev U.T.
2010-04-01
Full Text Available The neutron-proton mass diﬀerence in (isospin asymmetric nuclear matter and ﬁnite nuclei is studied in the framework of a medium-modiﬁed Skyrme model. The proposed eﬀective Lagrangian incorporates both the medium inﬂuence of the surrounding nuclear environment on the single nucleon properties and an explicit isospin-breaking eﬀect in the mesonic sector. Energy-dependent charged and neutral pion optical potentials in the s- and p-wave channels are included as well. The present approach predicts that the neutron-proton mass diﬀerence is mainly dictated by its strong part and that it markedly decreases in neutron matter. Furthermore, the possible interplay between the eﬀective nucleon mass in ﬁnite nuclei and the Nolen-Schiﬀer anomaly is discussed. In particular, we ﬁnd that a correct description of the properties of mirror nuclei leads to a stringent restriction of possible modiﬁcations of the nucleon’s eﬀective mass in nuclei.
Investigation of the proton-neutron interaction by high-precision nuclear mass measurements
Savreux, R P; Akkus, B
2007-01-01
We propose to measure the atomic masses of a series of short-lived nuclides, including $^{70}$Ni, $^{122-130}$Cd, $^{134}$Sn, $^{138,140}$Xe, $^{207-210}$Hg, and $^{223-225}$Rn, that contribute to the investigation of the proton-neutron interaction and its role in nuclear structure. The high-precision mass measurements are planned for the Penning trap mass spectrometer ISOLTRAP that reaches the required precision of 10 keV in the nuclear mass determination.
International Nuclear Information System (INIS)
Tamam, Muge; Mulazimoglu, Mehmet; Edis, Nurcan; Ozpacaci, Tevfik
2016-01-01
The purpose of this study was to evaluate the diagnostic value of attenuation-corrected single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) on the inferior wall compared to uncorrected (NC) SPECT MPI between obese and nonobese patients. A total of 157 consecutive patients (122 males and 35 females, with median age: 57.4 ± 11 years) who underwent AC technetium 99m-methoxyisobutylisonitrile (AC Tc99m-sestamibi) SPECT MPI were included to the study. A hybrid SPECT and transmission computed tomography (CT) system was used for the diagnosis with 1-day protocol, and stress imaging was performed first. During attenuation correction (AC) processing on a Xeleris Workstation using Myovation cardiac software with ordered subset expectation maximization (OSEM), iterative reconstruction with attenuation correction (IRAC) and NC images filtered back projection (FBP) were used. For statistical purposes, P < 0.05 was considered significant. This study included 73 patients with body mass index (BMI) <30 and 84 patients with BMI ≥ 30. In patients with higher BMI, increased amount of both visual and semiquantitative attenuation of the inferior wall was detected. IRAC reconstruction corrects the diaphragm attenuation of the inferior wall better than FBP. AC with OSEM iterative reconstruction significantly improves the diagnostic value of stress-only SPECT MPI in patients with normal weight and those who are obese, but the improvements are significantly greater in obese patients. Stress-only SPECT imaging with AC provides shorter and lower radiation exposure
Software in windows for staple compounding system of microcomputer nuclear mass scale
International Nuclear Information System (INIS)
Wang Yanting; Zhang Yongming; Wang Yu; Jin Dongping
1998-01-01
The software exploited in windows for staple compounding system of microcomputer nuclear mass scale is described. The staple compounding system is briefly narrated. The software structure and its realizing method are given
The mass media and nuclear energy in the U.S
International Nuclear Information System (INIS)
Roche, C.
1994-01-01
The author discusses some problems of mass media of the United States connected with covering issues of nuclear power development, and makes some recommendations to improve the situation in this field
Energy Technology Data Exchange (ETDEWEB)
Randrup, J.
1979-07-01
This lecture discusses a theory for the transport of mass, charge, linear, and angular momentum and energy in damped nuclear collisions, as induced by multiple transfer of individual nucleons. 11 references.
Energy Technology Data Exchange (ETDEWEB)
Benhamouda, N [Laboratoire de Physique Theoique, Faculte des Sciences, USTHB BP 32 El-Alia, 16111 Bab-Ezzouar, Algers (Algeria); Oudih, M R [CRNA, 2. Bd Frantz Fanon, BP 399 Alger-Gare, Algers (Algeria)
2002-09-15
A method of simultaneous evaluation of the shell and pairing corrections to the nuclear deformation energy, recently proposed for the even-even nuclei, is generalized to the case of odd systems. {sup *} By means of the blocked-level technique, a level density with explicit dependence on pairing correlations is defined. The microscopic corrections to the deformation energy are then determined by a procedure which is analogous to that of Strutinsky. The method is applied to the ground state of Europium isotopes using the single-particle energies of a deformed Woods-Saxon mean-field. The obtained results are in good agreement with the experimental values.
International Nuclear Information System (INIS)
Benhamouda, N.; Oudih, M.R.
2002-01-01
A method of simultaneous evaluation of the shell and pairing corrections to the nuclear deformation energy, recently proposed for the even-even nuclei, is generalized to the case of odd systems. * By means of the blocked-level technique, a level density with explicit dependence on pairing correlations is defined. The microscopic corrections to the deformation energy are then determined by a procedure which is analogous to that of Strutinsky. The method is applied to the ground state of Europium isotopes using the single-particle energies of a deformed Woods-Saxon mean-field. The obtained results are in good agreement with the experimental values
Nuclear mass formula with the shell energies obtained by a new method
International Nuclear Information System (INIS)
Koura, H.; Tachibana, T.; Yamada, M.; Uno, M.
1998-01-01
Nuclear shapes and masses are estimated by a new method. The main feature of this method lies in estimating shell energies of deformed nuclei from spherical shell energies by mixing them with appropriate weights. The spherical shell energies are calculated from single-particle potentials, and, till now, two mass formulas have been constructed from two different sets of potential parameters. The standard deviation of the calculated masses from all the experimental masses of the 1995 Mass Evaluation is about 760 keV. Contrary to the mass formula by Tachibana, Uno, Yamada and Yamada in the 1987-1988 Atomic Mass Predictions, the present formulas can give nuclear shapes and predict on super-heavy elements
Evolution of a 30 solar mass star: the interplay of nuclear burning and mass loss
International Nuclear Information System (INIS)
Falk, H.J.; Mitalas, R.
1981-01-01
Evolutionary tracks for a 30 solar mass star with various mass loss rates (MLR) were evolved to core He exhaustion. The 'overluminosity' of mass losing (ML) stars is explained in terms of the well known mass-luminosity (M-L) law. A critical ZAMS MLR above which mass loss leads to evolution to fainter luminosities is derived. Two tracks showed reversals in their direction of evolution across the HR diagram. These have been shown to be a consequence of mass loss dominating over the effects of the shell source. An analytic criterion for this condition has been derived. (Auth.)
Erratum to: Nuclear triaxiality in the A ∼ 160–170 mass region: the ...
Indian Academy of Sciences (India)
Erratum to: Nuclear triaxiality in the A ∼ 160–170 mass region: the story so far. S MUKHOPADHYAY1,∗ and W C MA2. 1Nuclear Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085, India. 2Department of Physics, Mississippi State University, Mississippi State, Mississippi 39762, USA. ∗. Corresponding ...
Two-loop top and bottom Yukawa corrections to the Higgs-boson masses in the complex MSSM
Paßehr, Sebastian; Weiglein, Georg
2018-03-01
Results for the two-loop corrections to the Higgs-boson masses of the MSSM with complex parameters of O{( α _t^2+α _tα _b+α _b^2) } from the Yukawa sector in the gauge-less limit are presented. The corresponding self-energies and their renormalization have been obtained in the Feynman-diagrammatic approach. The impact of the new contributions on the Higgs spectrum is investigated. Furthermore, a comparison with an existing result in the limit of the MSSM with real parameters is carried out. The new results will be included in the public code FeynHiggs.
Ito, Shinya; Tsukada, Katsuo
2002-01-11
An evaluation of the feasibility of liquid chromatography-mass spectrometry (LC-MS) with atmospheric pressure ionization was made for quantitation of four diarrhetic shellfish poisoning toxins, okadaic acid, dinophysistoxin-1, pectenotoxin-6 and yessotoxin in scallops. When LC-MS was applied to the analysis of scallop extracts, large signal suppressions were observed due to coeluting substances from the column. To compensate for these matrix signal suppressions, the standard addition method was applied. First, the sample was analyzed and then the sample involving the addition of calibration standards is analyzed. Although this method requires two LC-MS runs per analysis, effective correction of quantitative errors was found.
Two-loop top and bottom Yukawa corrections to the Higgs-boson masses in the complex MSSM
International Nuclear Information System (INIS)
Passehr, Sebastian; Weiglein, Georg
2017-05-01
Results for the two-loop corrections to the Higgs-boson masses of the MSSM with complex parameters of O(α 2 t +α t α b +α 2 b ) from the Yukawa sector in the gauge-less limit are presented. The corresponding self-energies and their renormalization have been obtained in the Feynman-diagrammatic approach. The impact of the new contributions on the Higgs spectrum is investigated. Furthermore, a comparison with an existing result in the limit of the MSSM with real parameters is carried out. The new results will be included in the public code FeynHiggs.
International Nuclear Information System (INIS)
Tudela, X.; Garcia-Vila, J. H.; Jornet, J.
2001-01-01
Stromal tumors of the gastrointestinal tract encompass a group of neoplasms representing 1% to 3% of all digestive system tumors. When located in the stomach, their tendency to exhibit and exophytic growth pattern makes it necessary to establish the differential diagnosis with respect to other gastric tumors (lymphoma, exophytic adenocarcinoma) and nongastrointestinal masses. We present a case that illustrated the difficulties associated with the imaging diagnosis of these lesions and the importance of modern radiological techniques (helical computed tomography and magnetic resonance) and the correct interpretation on the part of radiologists to orient pathologists and clinicians toward the diagnosis and proper treatment. (Author) 10 refs
Legleye, Stéphane; Beck, François; Spilka, Stanislas; Chau, Nearkasen
2014-01-01
To propose a simple correction of body-mass index (BMI) based on self-reported weight and height (reported BMI) using gender, body shape perception and socioeconomic status in an adolescent population. 341 boys and girls aged 17-18 years were randomly selected from a representative sample of 2165 French adolescents living in Paris surveyed in 2010. After an anonymous self-administered pen-and-paper questionnaire asking for height, weight, body shape perception (feeling too thin, about the right weight or too fat) and socioeconomic status, subjects were measured and weighed. BMI categories were computed according to Cole's cut-offs. Reported BMIs were corrected using linear regressions and ROC analyses and checked with cross-validation and multiple imputations to handle missing values. Agreement between actual and corrected BMI values was estimated with Kappa indexes and Intraclass correlation coefficients (ICC). On average, BMIs were underreported, especially among girls. Kappa indexes between actual and reported BMI were low, especially for girls: 0.56 95%CI = [0.42-0.70] for boys and 0.45 95%CI = [0.30-0.60] for girls. The regression of reported BMI by gender and body shape perception gave the most balanced results for both genders: the Kappa and ICC obtained were 0.63 95%CI = [0.50-0.76] and 0.67, 95%CI = [0.58-0.74] for boys; 0.65 95%CI = [0.52-0.78] and 0.74, 95%CI = [0.66-0.81] for girls. The regression of reported BMI by gender and socioeconomic status led to similar corrections while the ROC analyses were inaccurate. Using body shape perception, or socioeconomic status and gender is a promising way of correcting BMI in self-administered questionnaires, especially for girls.
Analyzing mass perceptions of nuclear politics: Puzzling over trust
International Nuclear Information System (INIS)
Jenkins-Smith, H.C.; Pratt, D.A.; Bassett, G.W. Jr.
1994-01-01
The juxtaposition of public values, trust, and beliefs is at the core of policy-making in democratic political systems, and an accurate understanding of nuclear politics requires that researchers untangle and carefully think about the web of psychological and social influences that shape citizens' preferences. In this paper, we offer some tentative answers about several pieces of the trust open-quotes puzzleclose quotes. First, we reconsider what is meant by open-quotes trustclose quotes and how it is to be measured. We then use telephone survey data to explore the relationship between trust and citizens' nuclear policy preferences. The data lend support to the conclusion that trust is more mutable than previous research has shown, and besides the traditional measure of competence includes aspects of believability and fiduciary competence. The data further indicate that it is a mistake to think in terms of a single open-quotes publicclose quotes when exploring the link between trust and nuclear policies. A number of dissimilar open-quotes publicsclose quotes based on shared open-quotes worldviewsclose quotes or political cultures are apparent in the data analyzed here. These open-quotes publicsclose quotes appear to think about trust differently from one another and rely on different dimensions of trust when determining nuclear policy preferences. Policy-makers must recognize the different open-quotes publicsclose quotes coexisting within the U.S. nuclear policy arena, and the relative import that these publics place on different dimensions of trust
Isospin Mass Splittings and the $\\ms$ Corrections in the Semibosonized SU(3)-NJL-Model
Blotz, Andree; Goeke, K.; Praszalowicz, M.
1994-01-01
The mass splittings of hyperons including the isospin splittings are calculated with $O(\\ms^2)$ and $O(\\ms \\dm)$ accuracy respectively within the semibosonized SU(3)-NJL model. The pattern of the isospin splittings is not spoiled by the terms of the order $O(\\ms \\dm)$, and both splittings between the different isospin multiplets and within the same multiplet are well reproduced for acceptable values of $\\ms$ and $\\dm$.
A Range Correction for Icesat and Its Potential Impact on Ice-sheet Mass Balance Studies
Borsa, A. A.; Moholdt, G.; Fricker, H. A.; Brunt, Kelly M.
2014-01-01
We report on a previously undocumented range error in NASA's Ice, Cloud and land Elevation Satellite (ICESat) that degrades elevation precision and introduces a small but significant elevation trend over the ICESat mission period. This range error (the Gaussian-Centroid or 'G-C'offset) varies on a shot-to-shot basis and exhibits increasing scatter when laser transmit energies fall below 20 mJ. Although the G-C offset is uncorrelated over periods less than1 day, it evolves over the life of each of ICESat's three lasers in a series of ramps and jumps that give rise to spurious elevation trends of -0.92 to -1.90 cm yr(exp -1), depending on the time period considered. Using ICESat data over the Ross and Filchner-Ronne ice shelves we show that (1) the G-C offset introduces significant biases in ice-shelf mass balance estimates, and (2) the mass balance bias can vary between regions because of different temporal samplings of ICESat.We can reproduce the effect of the G-C offset over these two ice shelves by fitting trends to sample-weighted mean G-C offsets for each campaign, suggesting that it may not be necessary to fully repeat earlier ICESat studies to determine the impact of the G-C offset on ice-sheet mass balance estimates.
Renormalization and radiative corrections to masses in a general Yukawa model
Fox, M.; Grimus, W.; Löschner, M.
2018-01-01
We consider a model with arbitrary numbers of Majorana fermion fields and real scalar fields φa, general Yukawa couplings and a ℤ4 symmetry that forbids linear and trilinear terms in the scalar potential. Moreover, fermions become massive only after spontaneous symmetry breaking of the ℤ4 symmetry by vacuum expectation values (VEVs) of the φa. Introducing the shifted fields ha whose VEVs vanish, MS¯ renormalization of the parameters of the unbroken theory suffices to make the theory finite. However, in this way, beyond tree level it is necessary to perform finite shifts of the tree-level VEVs, induced by the finite parts of the tadpole diagrams, in order to ensure vanishing one-point functions of the ha. Moreover, adapting the renormalization scheme to a situation with many scalars and VEVs, we consider the physical fermion and scalar masses as derived quantities, i.e. as functions of the coupling constants and VEVs. Consequently, the masses have to be computed order by order in a perturbative expansion. In this scheme, we compute the self-energies of fermions and bosons and show how to obtain the respective one-loop contributions to the tree-level masses. Furthermore, we discuss the modification of our results in the case of Dirac fermions and investigate, by way of an example, the effects of a flavor symmetry group.
Vainik, Uku; Konstabel, Kenn; Lätt, Evelin; Mäestu, Jarek; Purge, Priit; Jürimäe, Jaak
2016-10-01
Subjective energy intake (sEI) is often misreported, providing unreliable estimates of energy consumed. Therefore, relating sEI data to health outcomes is difficult. Recently, Börnhorst et al. compared various methods to correct sEI-based energy intake estimates. They criticised approaches that categorise participants as under-reporters, plausible reporters and over-reporters based on the sEI:total energy expenditure (TEE) ratio, and thereafter use these categories as statistical covariates or exclusion criteria. Instead, they recommended using external predictors of sEI misreporting as statistical covariates. We sought to confirm and extend these findings. Using a sample of 190 adolescent boys (mean age=14), we demonstrated that dual-energy X-ray absorptiometry-measured fat-free mass is strongly associated with objective energy intake data (onsite weighted breakfast), but the association with sEI (previous 3-d dietary interview) is weak. Comparing sEI with TEE revealed that sEI was mostly under-reported (74 %). Interestingly, statistically controlling for dietary reporting groups or restricting samples to plausible reporters created a stronger-than-expected association between fat-free mass and sEI. However, the association was an artifact caused by selection bias - that is, data re-sampling and simulations showed that these methods overestimated the effect size because fat-free mass was related to sEI both directly and indirectly via TEE. A more realistic association between sEI and fat-free mass was obtained when the model included common predictors of misreporting (e.g. BMI, restraint). To conclude, restricting sEI data only to plausible reporters can cause selection bias and inflated associations in later analyses. Therefore, we further support statistically correcting sEI data in nutritional analyses. The script for running simulations is provided.
Nuclear power debate - scientists, mass media and the public
International Nuclear Information System (INIS)
Rothman, S.; Lichter, S.R.
1983-01-01
A poll among the members of the American Men and Women of Science has shown that the majority of scientists are for nuclear energy. The controversial results of polls in the general public are believed to be due to the distortion effects of the press and media. The biased information role of the communication media might be the result of the prejudiced publicity behavior of antinuclear scientists. A more significant role, however, has been played by the science journalists whose scepticism toward nuclear power is reflected in the public opinion. There seems to be a lack in the communication chain connecting the layman public with the science community. (R.P.)
Nuclear Resonance Fluorescence to Measure Plutonium Mass in Spent Nuclear Fuel
Energy Technology Data Exchange (ETDEWEB)
Ludewigt, Bernhard A; Quiter, Brian J.; Ambers, Scott D.
2011-01-14
The Next Generation Safeguard Initiative (NGSI) of the U.S Department of Energy is supporting a multi-lab/university collaboration to quantify the plutonium (Pu) mass in spent nuclear fuel (SNF) assemblies and to detect the diversion of pins with non-destructive assay (NDA) methods. The following 14 NDA techniques are being studied: Delayed Neutrons, Differential Die-Away, Differential Die-Away Self-Interrogation, Lead Slowing Down Spectrometer, Neutron Multiplicity, Passive Neutron Albedo Reactivity, Total Neutron (Gross Neutron), X-Ray Fluorescence, {sup 252}Cf Interrogation with Prompt Neutron Detection, Delayed Gamma, Nuclear Resonance Fluorescence, Passive Prompt Gamma, Self-integration Neutron Resonance Densitometry, and Neutron Resonance Transmission Analysis. Understanding and maturity of the techniques vary greatly, ranging from decades old, well-understood methods to new approaches. Nuclear Resonance Fluorescence (NRF) is a technique that had not previously been studied for SNF assay or similar applications. Since NRF generates isotope-specific signals, the promise and appeal of the technique lies in its potential to directly measure the amount of a specific isotope in an SNF assay target. The objectives of this study were to design and model suitable NRF measurement methods, to quantify capabilities and corresponding instrumentation requirements, and to evaluate prospects and the potential of NRF for SNF assay. The main challenge of the technique is to achieve the sensitivity and precision, i.e., to accumulate sufficient counting statistics, required for quantifying the mass of Pu isotopes in SNF assemblies. Systematic errors, considered a lesser problem for a direct measurement and only briefly discussed in this report, need to be evaluated for specific instrument designs in the future. Also, since the technical capability of using NRF to measure Pu in SNF has not been established, this report does not directly address issues such as cost, size
Heat and mass transfer and hydrodynamics in two-phase flows in nuclear power plants
International Nuclear Information System (INIS)
Styrikovich, M.A.; Polonskii, V.S.; Tsiklauri, G.V.
1986-01-01
This book examines nuclear power plant equipment from the point of view of heat and mass transfer and the behavior of impurities contained in water and in steam, with reference to real water regimes of nuclear power plants. The transfer processes of equipment are considered. Heat and mass transfer are analyzed in the pre-crisis regions of steam-generating passages with non-permeable surfaces, and in capillary-porous structures. Attention is given to forced convection boiling crises and top post-DNB heat transfer. Data on two-phase hydrodynamics in straight and curved channels are correlated and safety aspects of nuclear power plants are discussed
Giusti, D.; Lubicz, V.; Martinelli, G.; Sanfilippo, F.; Simula, S.
2017-10-01
We present a lattice calculation of the Hadronic Vacuum Polarization (HVP) contribution of the strange and charm quarks to the anomalous magnetic moment of the muon including leading-order electromagnetic corrections. We employ the gauge configurations generated by the European Twisted Mass Collaboration (ETMC) with N f = 2 + 1 + 1 dynamical quarks at three values of the lattice spacing ( a ≃ 0 .062 , 0 .082 , 0 .089 fm) with pion masses in the range M π ≃ 210-450 MeV. The strange and charm quark masses are tuned at their physical values. Neglecting disconnected diagrams and after the extrapolations to the physical pion mass and to the continuum limit we obtain: a μ s ( α em 2 ) = (53.1 ± 2.5) · 10- 10, a μ s ( α em 3 ) = (-0.018 ± 0.011) · 10- 10 and a μ c ( α em 2 ) = (14.75 ± 0.56) · 10- 10, a μ c ( α em 3 ) = (-0.030 ± 0.013) · 10- 10 for the strange and charm contributions, respectively.
Mass Media and the Debate about Nuclear Power.
Sawyer, Thomas M.
Many factors contribute to the difficulties the media have in dealing with science, engineering, and technology. These difficulties were pointed up in the media coverage of the March 1979 accident at the Three Mile Island nuclear plant, which reflected confusion and lack of understanding and which combined with other factors (including the movie…
Determination of B and Li in nuclear materials by secondary-ion mass spectrometry
International Nuclear Information System (INIS)
Eby, R.E.; Christie, W.H.
1981-01-01
Secondary ion mass spectrometry (SIMS) was used to perform mass and isotopic analysis for B and Li in samples that are not readily amenable to more conventional mass spectrometric techniques (e.g., surface ionization, electron impact, etc.). In this paper three specific applications of SIMS analysis to nuclear materials are discussed: first, the quantitative determination of B and its isotopic composition in borosilicate glasses; second, the determination of the isotopic composition of B and Li in irradiated nuclear-grade aluminum oxide/boron carbide composite pellets, and, lastly, the quantitative and isotopic determination of B and Li in highly radioactive solutions of unknown composition
Gibbons, S. J.; Pabian, F.; Näsholm, S. P.; Kværna, T.; Mykkeltveit, S.
2017-01-01
Declared North Korean nuclear tests in 2006, 2009, 2013 and 2016 were observed seismically at regional and teleseismic distances. Waveform similarity allows the events to be located relatively with far greater accuracy than the absolute locations can be determined from seismic data alone. There is now significant redundancy in the data given the large number of regional and teleseismic stations that have recorded multiple events, and relative location estimates can be confirmed independently by performing calculations on many mutually exclusive sets of measurements. Using a 1-D global velocity model, the distances between the events estimated using teleseismic P phases are found to be approximately 25 per cent shorter than the distances between events estimated using regional Pn phases. The 2009, 2013 and 2016 events all take place within 1 km of each other and the discrepancy between the regional and teleseismic relative location estimates is no more than about 150 m. The discrepancy is much more significant when estimating the location of the more distant 2006 event relative to the later explosions with regional and teleseismic estimates varying by many hundreds of metres. The relative location of the 2006 event is challenging given the smaller number of observing stations, the lower signal-to-noise ratio and significant waveform dissimilarity at some regional stations. The 2006 event is however highly significant in constraining the absolute locations in the terrain at the Punggye-ri test-site in relation to observed surface infrastructure. For each seismic arrival used to estimate the relative locations, we define a slowness scaling factor which multiplies the gradient of seismic traveltime versus distance, evaluated at the source, relative to the applied 1-D velocity model. A procedure for estimating correction terms which reduce the double-difference time residual vector norms is presented together with a discussion of the associated uncertainty. The modified
Jet energy scale corrections and their impact on measurements of the top-quark mass at CMS
International Nuclear Information System (INIS)
Kirschenmann, Henning
2014-10-01
The final state of many physics processes at the Large Hadron Collider (LHC) is dominated by jets, the experimental signature of quarks and gluons. The precise measurement of jets is a prerequisite to understand these processes. In this thesis, the determination of jet-energy corrections at CMS using dijet events is described, and the investigation of a correction specifically tailored to improve the reconstruction of b-jets in top-quark mass measurements is presented. Dijet events are used to determine the response relative to the central detector region in data and simulation as a function of the pseudorapidity η. Two complementary response estimators are introduced and detailed supplementary studies, e.g. of the time stability of the response, are performed. For the 2011 data-taking period, the MC/Data differences are found to be below 5% in the tracker-covered detector region with systematic uncertainties of less than 1%. Furthermore, a study of b-jet properties in 2012 data is presented. The correlation of various such observables with the response is exploited to improve the jet-energy measurement of b-jets. A resolution improvement of about 10% can be achieved, and the evaluation of b-jet specific jet-energy scale uncertainties (b-JES) indicates improvements of about 30%. This additional correction is applied to an existing measurement of the top-quark mass in the muon+jets channel. It leads to a statistical sensitivity improvement of about 10% and a reduction of systematic uncertainties related to the b-JES from 0.6 GeV to 0.3 GeV.
Coplen, Tyler B.; Brand, Willi A.; Assonov, Sergey S.
2010-01-01
Measurements of δ(13C) determined on CO2 with an isotope-ratio mass spectrometer (IRMS) must be corrected for the amount of 17O in the CO2. For data consistency, this must be done using identical methods by different laboratories. This report aims at unifying data treatment for CO2 IRMS by proposing (i) a unified set of numerical values, and (ii) a unified correction algorithm, based on a simple, linear approximation formula. Because the oxygen of natural CO2 is derived mostly from the global water pool, it is recommended that a value of 0.528 be employed for the factor λ, which relates differences in 17O and 18O abundances. With the currently accepted N(13C)/N(12C) of 0.011 180(28) in VPDB (Vienna Peedee belemnite) reevaluation of data yields a value of 0.000 393(1) for the oxygen isotope ratio N(17O)/N(16O) of the evolved CO2. The ratio of these quantities, a ratio of isotope ratios, is essential for the 17O abundance correction: [N(17O)/N(16O)]/[N(13C)/N(12C)] = 0.035 16(8). The equation [δ(13C) ≈ 45δVPDB-CO2 + 2 17R/13R (45δVPDB-CO2 – λ46δVPDB-CO2)] closely approximates δ(13C) values with less than 0.010 ‰ deviation for normal oxygen-bearing materials and no more than 0.026 ‰ in extreme cases. Other materials containing oxygen of non-mass-dependent isotope composition require a more specific data treatment. A similar linear approximation is also suggested for δ(18O). The linear approximations are easy to implement in a data spreadsheet, and also help in generating a simplified uncertainty budget.
Role of deformed shell effects on the mass asymmetry in nuclear fission of mercury isotopes
International Nuclear Information System (INIS)
Panebianco, Stefano; Sida, Jean-Luc; Goutte, Heloise; Lemaitre, Jean-Francois; Dubray, Noel; Hilaire, Stephane
2012-01-01
Until now, the mass asymmetry in the nuclear fission process has been understood in terms of the strong influence of the nuclear structure of the nascent fragments. Recently, a surprising asymmetric fission has been discovered in the light mercury region and has been interpreted as the result of the influence of the nuclear structure of the parent nucleus, totally discarding the influence of the fragments' structure. To assess the role of the fragment shell effects in the mass asymmetry in this particular region, a scission-point model, based on a full energy balance between the two nascent fragments, has been developed using one of the best theoretical descriptions of microscopic nuclear structure. As for actinides, this approach shows that the asymmetric splitting of the Hg-180 nucleus and the symmetric one of Hg-198 can be understood on the basis of only the microscopic nuclear structure of the fragments at scission. (authors)
Strange mass corrections to hyperonic semi-leptonic decays in statistical model
Energy Technology Data Exchange (ETDEWEB)
Upadhyay, A.; Batra, M. [Thapar University, School of Physics and Material Science, Patiala (India)
2013-12-15
We study the spin distribution, weak decay coupling constant ratios for strange baryon octets with SU(3) breaking effects. Baryon is taken as an ensemble of quark-gluon Fock states in the sea with three valence quarks with definite spin, color and flavor quantum numbers. We apply the statistical model to calculate the probabilities of each Fock states, to analyze the impact of SU(3) breaking in the weak decays. The symmetry breaking effects are studied in terms of a parameter ''r '' whose best-fit value is obtained from the experimental data of semi-leptonic weak decay coupling constant ratios. We suggest the dominant contribution from H{sub 1}G{sub 8} (sea with spin one and color octet) where symmetry breaking corrections lead to the deviations in the value of the axial-vector matrix elements ratio F/D from experimental values by 17%. We conclude that symmetry breaking also significantly affects the polarization of quark in strange baryons. (orig.)
International Nuclear Information System (INIS)
Sidorov, A.V.; Tokarev, M.V.
1997-01-01
A detailed NNLO QCD analysis of new CCFR data on xF 3 structure function including the target mass, higher twist and nuclear corrections was performed and parametrizations of the perturbative and power terms of the structure function were constructed. The results of QDC analysis of the structure function were used to study the Q 2 -dependence of the Gross-Llewellyn-Smith sum rule. The α s /π-expansion of S GLS (Q 2 ) was studied and parameters of the expansion were found to be s 1 =2.74±0.01, s 2 =-2.22±0.23, s 3 =-7.86±1.74 which are in good agreement with the perturbative QCD predictions for the Gross-Llewellyn-Smith sum rule in the next-to-leading and next-to-next-leading order
International Nuclear Information System (INIS)
Sidorov, A.V.; Tokarev, M.V.
1997-01-01
A detailed NNLO QCD analysis of new CCFR data on xF 3 structure function including the target mass, higher twist and nuclear corrections was performed and parametrizations of the perturbative and power terms of the structure function were constructed. The results of QCD analysis of the structure function were used to study the Q 2 -dependence of the Gross-Llewellyn Smith sum rule. The α S /π-expansion of S GLS (Q 2 ) was studied and parameters of the expansion were found to be s 1 =2.74±0.01, s 2 =-2.22±0.23, s 3 =-7.86±1.74 which are in good agreement with the perturbative QCD predictions for the Gross-Llewellyn Smith sum rule in the next-to-leading and next-to-next-to-leading order
Feng, W.; Lemoine, J.-M.; Zhong, M.; Hsu, H. T.
2014-08-01
An annual amplitude of ∼18 cm mass-induced sea level variations (SLV) in the Red Sea is detected from the Gravity Recovery and Climate Experiment (GRACE) satellites and steric-corrected altimetry from 2003 to 2011. The annual mass variations in the region dominate the mean SLV, and generally reach maximum in late January/early February. The annual steric component of the mean SLV is relatively small (mass-induced SLV. In situ bottom pressure records at the eastern coast of the Red Sea validate the high mass variability observed by steric-corrected altimetry and GRACE. In addition, the horizontal water mass flux of the Red Sea estimated from GRACE and steric-corrected altimetry is validated by hydrographic observations.
Nuclear masses and the number of valence nucleons
International Nuclear Information System (INIS)
Mendoza-Temis, J.; Frank, A.; Hirsch, J.G.; Lopez Vieyra, J.C.; Morales, I.; Barea, J.; Van Isacker, P.; Velazquez, V.
2008-01-01
An improved version of the liquid drop model is presented. The addition of two terms, linear and quadratic in the total number of valence nucleons (particles or holes), improves the description of atomic masses, which can be fitted with an r.m.s. error of 1.2 MeV. Predictions are analysed an compared with those of established models
Energy Technology Data Exchange (ETDEWEB)
Conti, C.C., E-mail: ccconti@ird.gov.br [Institute for Radioprotection and Dosimetry – IRD/CNEN, Rio de Janeiro (Brazil); Physics Institute, State University of Rio de Janeiro – UERJ, Rio de Janeiro (Brazil); Anjos, M.J. [Physics Institute, State University of Rio de Janeiro – UERJ, Rio de Janeiro (Brazil); Salgado, C.M. [Nuclear Engineering Institute – IEN/CNEN, Rio de Janeiro (Brazil)
2014-09-15
Highlights: •This work describes a procedure for sample self-absorption correction. •The use of Monte Carlo simulation to calculate the mass attenuation coefficients curve was effective. •No need for transmission measurement, saving time, financial resources and effort. •This article provides de curves for the 90° scattering angle. •Calculation on-line at (www.macx.net.br). -- Abstract: X-ray fluorescence technique plays an important role in nondestructive analysis nowadays. The development of equipment, including portable ones, enables a wide assortment of possibilities for analysis of stable elements, even in trace concentrations. Nevertheless, despite of the advantages, one important drawback is radiation self-attenuation in the sample being measured, which needs to be considered in the calculation for the proper determination of elemental concentration. The mass attenuation coefficient can be determined by transmission measurement, but, in this case, the sample must be in slab shape geometry and demands two different setups and measurements. The Rayleigh to Compton scattering ratio, determined from the X-ray fluorescence spectrum, provides a link to the mass attenuation coefficient by means of a polynomial type equation. This work presents a way to construct a Rayleigh to Compton scattering ratio versus mass attenuation coefficient curve by using the MCNP5 Monte Carlo computer code. The comparison between the calculated and literature values of the mass attenuation coefficient for some known samples showed to be within 15%. This calculation procedure is available on-line at (www.macx.net.br)
Energy Technology Data Exchange (ETDEWEB)
Krivanek, Robert, E-mail: r.krivanek@iaea.org [International Atomic Energy Agency (IAEA), Department of Nuclear Safety and Security, Operational Safety Section, Vienna 1400 (Austria); Fiedler, Jan, E-mail: fiedler@fme.vutbr.cz [University of Technology Brno, Faculty of Mechanical Engineering, Energy Institute, Technická 2896/2, 616 69 Brno (Czech Republic)
2017-05-15
Highlights: • Results of SALTO missions provide the most important issues for safe long term operation (LTO) of nuclear power plants. • The most important technical corrective measures in an early phase of preparation for safe LTO are described. • Their satisfactory resolution creates a basis for further activities to demonstrate preparedness for safe LTO. - Abstract: This paper presents the analysis of main technical deficiencies of nuclear power plants (NPPs) in preparedness for safe long term operation (LTO) and the main corrective measures in an early phase of preparation for safe LTO of NPPs. It focuses on technical aspects connected with management of physical ageing of NPP structures, systems and components (SSCs). It uses as a basis results of IAEA SALTO missions performed between 2005 and 2016 (see also paper NED8805 in Nuclear Engineering and Design in May 2016) and the personal experiences of the authors with preparation of NPPs for safe LTO. This paper does not discuss other important aspects of safe LTO of NPPs, e.g. national nuclear energy policies, compliance of NPPs with the latest international requirements on design, obsolescence, environmental impact and economic aspects of LTO. Chapter 1 provides a brief introduction of the current status of the NPP’ fleet in connection with LTO. Chapter 2 provides an overview of SALTO peer review service results with a focus on deficiencies related to physical ageing of safety SSCs and a demonstration that SSCs will perform their safety function during the intended period of LTO. Chapter 3 discusses the main corrective measures which NPPs typically face during the preparation for demonstration of safe LTO. Chapter 4 summarizes the current status of the NPP’ fleet in connection with LTO and outlines further steps needed in preparation for safe LTO.
Nuclear-polarization correction to the bound-electron g factor in heavy hydrogenlike ions
Nefiodov, A. V.; Plunien, G.; Soff, G.
2002-01-01
The influence of nuclear polarization on the bound-electron $g$ factor in heavy hydrogenlike ions is investigated. Numerical calculations are performed for the K- and L-shell electrons taking into account the dominant virtual nuclear excitations. This determines the ultimate limit for tests of QED utilizing measurements of the bound-electron $g$ factor in highly charged ions.
Nuclear-polarization correction to the bound-electron g factor in heavy hydrogenlike ions.
Nefiodov, A V; Plunien, G; Soff, G
2002-08-19
The influence of nuclear polarization on the bound-electron g factor in heavy hydrogenlike ions is investigated. Numerical calculations are performed for the K- and L-shell electrons taking into account the dominant virtual nuclear excitations. This determines the ultimate limit for tests of QED utilizing measurements of the bound-electron g factor in highly charged ions.
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)
Detailed study of nuclear charge and mass densities. Pt. 1
International Nuclear Information System (INIS)
Berdichevsky, D.; Mosel, U.
1982-01-01
Theoretical and experimental densities are analyzed and compared in detail, in particular in the surface region. For this purpose nuclear size parameters are discussed and new sets of surface parameters are proposed. It is shown that the densities are very close to the error function in the external part of the surface and can be characterized there by two new parameters. For very large r the densities show an exponential behaviour which is analyzed in terms of single-particle density distributions. Furthermore, the effects of the asymmetry, spin-orbit and Coulomb forces on the density distributions are discussed. (orig.)
Nuclear equipment to determine soil and water mass attenuation coefficients
International Nuclear Information System (INIS)
Zucchi, O.L.A.D.; Nascimento Filho, V.F. do
1984-01-01
The feasibility of substituting the monochannel gamma spectrometer, traditionally used in the gamma ray attenuation technique, for a less sophisticated and less expensive system of integral counting is studied. The proposed system can be operated by a non-specialized person. Three detection systems were used in the determination of the mass attenuation coefficients for different types of soil and for water. (M.A.C.) [pt
Mass and charge distributions in chlorine-induced nuclear reactions
International Nuclear Information System (INIS)
Marchetti, A.A.
1991-01-01
Projectile-like fragments were detected and characterized in terms of A, Z, and energy for the reactions 37 Cl on 40 Ca and 209 Bi at E/A = 7.3 MeV, and 35 Cl, on 209 Bi at E/A = 15 MeV, at angles close to the grazing angle. Mass and charge distributions were generated in the N-Z plane as a function of energy loss, and have been parameterized in terms of their centroids, variances, and coefficients of correlation. Due to experimental problems, the mass resolution corresponding to the 31 Cl on 209 Bi reaction was very poor. This prompted the study and application of a deconvolution technique for peak enhancement. The drifts of the charge and mass centroids for the system 37 Cl on 40 Ca are consistent with a process of mass and charge equilibration mediated by nucleon exchange between the two partners, followed by evaporation. The asymmetric systems show a strong drift towards larger asymmetry, with the production of neutron-rich nuclei. It was concluded that this is indicative of a net transfer of protons from the light to the heavy partner, and a net flow of neutrons in the opposite direction. The variances for all systems increase with energy loss, as it would be expected from a nucleon exchange mechanism; however, the variances for the reaction 37 Cl on 40 Ca are higher than those expected from that mechanism. The coefficients of correlation indicate that the transfer of nucleons between projectile and target is correlated. The results were compared to the predictions of two current models based on a stochastic nucleon exchange mechanism. In general, the comparisons between experimental and predicted variances support this mechanism; however, the need for more realistic driving forces in the model calculations is indicated by the disagreement between predicted and experimental centroids
Steam Generator control in Nuclear Power Plants by water mass inventory
Energy Technology Data Exchange (ETDEWEB)
Dong Wei [North Carolina State University, Department of Nuclear Engineering, Box 7909, Raleigh, NC 27695-7909 (United States); Doster, J. Michael [North Carolina State University, Department of Nuclear Engineering, Box 7909, Raleigh, NC 27695-7909 (United States)], E-mail: doster@eos.ncsu.edu; Mayo, Charles W. [North Carolina State University, Department of Nuclear Engineering, Box 7909, Raleigh, NC 27695-7909 (United States)
2008-04-15
Control of water mass inventory in Nuclear Steam Generators is important to insure sufficient cooling of the nuclear reactor. Since downcomer water level is measurable, and a reasonable indication of water mass inventory near steady-state, conventional feedwater control system designs attempt to maintain downcomer water level within a relatively narrow operational band. However, downcomer water level can temporarily react in a reverse manner to water mass inventory changes, commonly known as shrink and swell effects. These complications are accentuated during start-up or low power conditions. As a result, automatic or manual control of water level is difficult and can lead to high reactor trip rates. This paper introduces a new feedwater control strategy for Nuclear Steam Generators. The new method directly controls water mass inventory instead of downcomer water level, eliminating complications from shrink and swell all together. However, water mass inventory is not measurable, requiring an online estimator to provide a mass inventory signal based on measurable plant parameters. Since the thermal-hydraulic response of a Steam Generator is highly nonlinear, a linear state-observer is not feasible. In addition, difficulties in obtaining flow regime and density information within the Steam Generator make an estimator based on analytical methods impractical at this time. This work employs a water mass estimator based on feedforward neural networks. By properly choosing and training the neural network, mass signals can be obtained which are suitable for stable, closed-loop water mass inventory control. Theoretical analysis and simulation results show that water mass control can significantly improve the operation and safety of Nuclear Steam Generators.
Steam Generator control in Nuclear Power Plants by water mass inventory
International Nuclear Information System (INIS)
Dong Wei; Doster, J. Michael; Mayo, Charles W.
2008-01-01
Control of water mass inventory in Nuclear Steam Generators is important to insure sufficient cooling of the nuclear reactor. Since downcomer water level is measurable, and a reasonable indication of water mass inventory near steady-state, conventional feedwater control system designs attempt to maintain downcomer water level within a relatively narrow operational band. However, downcomer water level can temporarily react in a reverse manner to water mass inventory changes, commonly known as shrink and swell effects. These complications are accentuated during start-up or low power conditions. As a result, automatic or manual control of water level is difficult and can lead to high reactor trip rates. This paper introduces a new feedwater control strategy for Nuclear Steam Generators. The new method directly controls water mass inventory instead of downcomer water level, eliminating complications from shrink and swell all together. However, water mass inventory is not measurable, requiring an online estimator to provide a mass inventory signal based on measurable plant parameters. Since the thermal-hydraulic response of a Steam Generator is highly nonlinear, a linear state-observer is not feasible. In addition, difficulties in obtaining flow regime and density information within the Steam Generator make an estimator based on analytical methods impractical at this time. This work employs a water mass estimator based on feedforward neural networks. By properly choosing and training the neural network, mass signals can be obtained which are suitable for stable, closed-loop water mass inventory control. Theoretical analysis and simulation results show that water mass control can significantly improve the operation and safety of Nuclear Steam Generators
International Nuclear Information System (INIS)
Chiba, Gou
2001-12-01
The fast reactor group constant set JFS-3-J3.2 based on the newest evaluated nuclear data library JENDL-3.2 has been widely used in the fast reactor analysis. However, it was recently found that there was a serious error in the process of applying the weighting function, a collision density spectrum in the inner core of ''MONJU'' as a representative of fast reactor spectrum. In this report, an effect of the error on nuclear characteristics was evaluated by a comparison with a new reactor group constant set which was produced by a standard reactor group constant set producing system of JNC with a correction of the weighting function. This report shows that the error of weighting function induces incorrect evaluation of neutron energy spectrum due to underestimation of scattering removal cross sections, and hence nuclear characteristics, such as criticality, sample Doppler reactivity, sodium void reactivity and reaction rate in a blanket region, are significantly affected. In addition, this report provides detailed information evaluated by separating ''an effect of new generation reactor group constant'' into more specific effects (i.e. an effect of correcting weighting function, an effect of differences in used cell codes and an effect of ultra fine group constant), which would be useful to investigate further on ''an effect of new generation reactor group constant''. (author)
Two-loop top and bottom Yukawa corrections to the Higgs-boson masses in the complex MSSM
Energy Technology Data Exchange (ETDEWEB)
Passehr, Sebastian; Weiglein, Georg
2017-05-15
Results for the two-loop corrections to the Higgs-boson masses of the MSSM with complex parameters of O(α{sup 2}{sub t}+α{sub t}α{sub b}+α{sup 2}{sub b}) from the Yukawa sector in the gauge-less limit are presented. The corresponding self-energies and their renormalization have been obtained in the Feynman-diagrammatic approach. The impact of the new contributions on the Higgs spectrum is investigated. Furthermore, a comparison with an existing result in the limit of the MSSM with real parameters is carried out. The new results will be included in the public code FeynHiggs.
Khoma, Mykhaylo; Jaquet, Ralph
2017-09-21
The kinetic energy operator for triatomic molecules with coordinate or distance-dependent nuclear masses has been derived. By combination of the chain rule method and the analysis of infinitesimal variations of molecular coordinates, a simple and general technique for the construction of the kinetic energy operator has been proposed. The asymptotic properties of the Hamiltonian have been investigated with respect to the ratio of the electron and proton mass. We have demonstrated that an ad hoc introduction of distance (and direction) dependent nuclear masses in Cartesian coordinates preserves the total rotational invariance of the problem. With the help of Wigner rotation functions, an effective Hamiltonian for nuclear motion can be derived. In the derivation, we have focused on the effective trinuclear Hamiltonian. All necessary matrix elements are given in closed analytical form. Preliminary results for the influence of non-adiabaticity on vibrational band origins are presented for H 3 + .
Jochimsen, Thies H.; Schulz, Jessica; Busse, Harald; Werner, Peter; Schaudinn, Alexander; Zeisig, Vilia; Kurch, Lars; Seese, Anita; Barthel, Henryk; Sattler, Bernhard; Sabri, Osama
2015-06-01
This study explores the possibility of using simultaneous positron emission tomography—magnetic resonance imaging (PET-MRI) to estimate the lean body mass (LBM) in order to obtain a standardized uptake value (SUV) which is less dependent on the patients' adiposity. This approach is compared to (1) the commonly-used method based on a predictive equation for LBM, and (2) to using an LBM derived from PET-CT data. It is hypothesized that an MRI-based correction of SUV provides a robust method due to the high soft-tissue contrast of MRI. A straightforward approach to calculate an MRI-derived LBM is presented. It is based on the fat and water images computed from the two-point Dixon MRI primarily used for attenuation correction in PET-MRI. From these images, a water fraction was obtained for each voxel. Averaging over the whole body yielded the weight-normalized LBM. Performance of the new approach in terms of reducing variations of 18F-Fludeoxyglucose SUVs in brain and liver across 19 subjects was compared with results using predictive methods and PET-CT data to estimate the LBM. The MRI-based method reduced the coefficient of variation of SUVs in the brain by 41 ± 10% which is comparable to the reduction by the PET-CT method (35 ± 10%). The reduction of the predictive LBM method was 29 ± 8%. In the liver, the reduction was less clear, presumably due to other sources of variation. In conclusion, employing the Dixon data in simultaneous PET-MRI for calculation of lean body mass provides a brain SUV which is less dependent on patient adiposity. The reduced dependency is comparable to that obtained by CT and predictive equations. Therefore, it is more comparable across patients. The technique does not impose an overhead in measurement time and is straightforward to implement.
Mass casualties of radiation injuries after nuclear weapon explosion
International Nuclear Information System (INIS)
Messerschmidt, O.
1980-01-01
Burns, mechanical lesions, radiation injuries as well as combinations of these types of injuries as a consequence of a nuclear explosion demand different basic lines of triage. The lack of a suitable physical dosimetry is a special problem for the evaluation of radiation injuries. While in cases of wounds and burns treatment, like surgery, is recommended to take place early, for example, within hours or days after those injuries, treatment of radiation victims is necessary only in the stage of severe haematologic changes including disturbances of coagulation and occurrence of high fever which appears after one or two weeks subsequent to exposure. The lack of medical personnel and medical equipment result in even a worse prognosis for the various injuries than in peace time accidents. (orig.) [de
Fukushima Nuclear Accident: Sticking to the facts, not to the political correctness
Ohska, Tokio
2014-05-01
The Fukushima Nuclear Reactor disaster of 2011 is still a continuing disaster three years later, although some experts have proclaimed the 4 reactors being already under control. It is surely an incredibly difficult task to properly terminate nuclear accidents. However, I should point out that the process of termination plan has been marred by too much of politics and business messing up a scientific approach to do it in a rational way. This blame must to go to both pro-nuclear and anti-nuclear power people. It makes me feel sad to see people not respecting science in executing such a difficult task. I shall list up where things went wrong with the hope that this kind of action, as I do here, would trigger people to get back to science to straighten out the execution process. I will show a few examples of published papers presenting the opinion that it is inappropriate what the Japanese government considers to be safe.
Onsets of nuclear deformation from measurements with the Isoltrap mass spectrometer
International Nuclear Information System (INIS)
Naimi, S.
2010-10-01
Mass measurements provide important information concerning nuclear structure. This work presents results from the pioneering Penning trap spectrometer Isoltrap at CERN-Isolde. High-precision mass measurements of neutron-rich manganese ( 58 - 66 Mn) and krypton isotopes ( 96, 97 Kr) are presented, of which the 66 Mn and 96, 97 Kr masses are measured for the first time. In particular, the mass of 97 Kr was measured using the preparation trap and required the definition of a new fit function. In the case of the manganese isotopes, the N=40 shell closure is addressed. The two-neutron-separation energies calculated from the new masses show no shell closure at N=40 but give an estimation of the proton-neutron interaction (around 0.5 MeV) responsible for the increase of collectivity and nuclear deformation in this mass region. The new krypton masses show behavior in sharp contrast with heavier neighbors where sudden and intense deformation is present, interpreted as the establishment of a nuclear quantum shape/phase transition critical-point boundary. The new masses confirm findings from nuclear mean-square charge-radius measurements up to N=60 but are at variance with conclusions from recent gamma-ray spectroscopy. Another part of this work was the design of new decay spectroscopy system behind the Isoltrap mass spectrometer. The beam purity achievable with Isoltrap will allow decay studies with γ and β detection coupled to a tape-station. This system has been mounted and commissioned with the radioactive beam 80 Rb. (author)
Rock mass characterization for storage of nuclear waste in granite
International Nuclear Information System (INIS)
Witherspoon, P.A.; Nelson, P.; Doe, T.; Thorpe, R.; Paulsson, B.; Gale, J.; Forster, C.
1979-02-01
The rock mass characterization in granite adjacent to an iron mine at Stripa, Sweden is being carried out by four different methods. The mechanical characterization includes monitoring the responses to thermal loading of jointed rock in situ, and mechanical tests on cores from 25 mm to 1 m in diameter. Geological characterization includes detailed surface mapping, subsurface mapping, and core mapping. Geophysical characterization uses a variety of borehole techniques, with emphasis on sonic methods. The hydrologic characterization is done through injection tests, pump tests, water pressure measurements, and controlled inflow tests to tunnels. Since the data are not yet complete, only tentative conclusions can be drawn regarding the best combinations of techniques for rock-mass characterization. Mapping studies are useful in defining continuity and fracture-system geometry. They do not give aperture, a factor significant in terms of both water flow and the displacements due to heating. Of the geophysical techniques, sonic methods appear most effective in fracture definition; other methods, gamma and neutron particularly, give data on radionuclide and water content and need further analysis with geologic and hydrologic data to determine their significance. Hydrologic work yields primarily aperture data, which with fracture geometry can be used to calculate directional permeabilities. Pressure measurements may provide one means of assessing fracture continuity. Finally, laboratory tests on large cores suggest considerable refinement in testing techniques may be needed before stress-aperture data can be extrapolated from laboratory to field
International Nuclear Information System (INIS)
Lindborg, L.; Bolognese-Milsztajn, T.; Boschung, M.; Coeck, M.; Curzio, G.; D'Errico, F.; Fiechtner, A.; Hallfarth, D.; Lievens, B.; Lillhoek, J. E.; Loevefors-Daun, A.; Lacoste, V.; Luszik-Bhadra, M.; Reginatto, M.; Schuhmacher, H.; Tanner, R.; Vanhavere, F.
2007-01-01
Ratios of H p (10) and H*(10) were determined with reference instruments in a number of workplace fields within the nuclear industry and used to derive workplace-specific correction factors. When commercial survey meter results together with these factors were applied to the results of the locally used personal dosemeters their results improved and became within 0.7 and 1.7 of the reference values or better depending on the response of the survey meter. A similar result was obtained when a correction was determined with a prototype reference instrument for H p (10) after adjustment of its response. Commercially available survey instruments both for photon and neutron H*(10) measurements agreed with the reference instruments in most cases to within 0.5-1.5. Those conclusions are derived from results reported within the EC supported EVIDOS contract. (authors)
Volumes, Masses, and Surface Areas for Shippingport LWBR Spent Nuclear Fuel in a DOE SNF Canister
International Nuclear Information System (INIS)
J.W. Davis
1999-01-01
The purpose of this calculation is to estimate volumes, masses, and surface areas associated with (a) an empty Department of Energy (DOE) 18-inch diameter, 15-ft long spent nuclear fuel (SNF) canister, (b) an empty DOE 24-inch diameter, 15-ft long SNF canister, (c) Shippingport Light Water Breeder Reactor (LWBR) SNF, and (d) the internal basket structure for the 18-in. canister that has been designed specifically to accommodate Seed fuel from the Shippingport LWBR. Estimates of volumes, masses, and surface areas are needed as input to structural, thermal, geochemical, nuclear criticality, and radiation shielding calculations to ensure the viability of the proposed disposal configuration
International Nuclear Information System (INIS)
Williams, A.; Williams, J.
1975-01-01
The technical and political issues of diversion safeguards are at best confusing to the general public, who derive most of their information about nuclear science from the mass media. This investigation compared ''nuclear news'' of all kinds in three national mass media for thirty-three months of 1972-1974 to examine the quantity and quality of atom-related news they provide. Findings from The New York Times, U. S. News and World Report, and the ABC, CBS, and NBC evening news indicate grounds for low public familiarity with essential concepts of safeguards, and consequently, for consumer value conflicts and weak popular supports for safeguards-related policy
One-pion exchange current corrections for nuclear magnetic moments in relativistic mean field theory
International Nuclear Information System (INIS)
Li Jian; Yao, J.M.; Meng Jie; Arima, Akito
2011-01-01
The one-pion exchange current corrections to isoscalar and isovector magnetic moments of double-closed shell nuclei plus and minus one nucleon with A = 15, 17, 39 and 41 have been studied in the relativistic mean field (RMF) theory and compared with previous relativistic and non-relativistic results. It has been found that the one-pion exchange current gives a negligible contribution to the isoscalar magnetic moments but a significant correction to the isovector ones. However, the one-pion exchange current enhances the isovector magnetic moments further and does not improve the corresponding description for the concerned nuclei in the present work. (author)
Thomas-Fermi treatment of nuclear masses, deformations and density distributions
International Nuclear Information System (INIS)
Myers, W.D.; Swiatecki, W.J.
1994-08-01
A recently completed Thomas-Fermi model of nuclei is described. Six adjustable parameters of the effective nucleon-nucleon interaction were fitted to the shell-corrected binding energies of 1654 nuclei and to the diffuseness of the nuclear surface. The model is then successful in reproducing nuclear sizes, and only small deviations are found between calculated and measured fission barriers of 36 nuclei. The model is applied to the prediction of fission barriers of light elements, to drip-line nuclei like 82 Sn and 170 Sn, to the properties of nuclear and neutron matter and to nuclear bubble configurations with Z 2 /A ∼ 100. The relation of a Thomas-Fermi theory to the Droplet and Liquid Drop models is illustrated
Faustov, R. N.; Martynenko, A. P.; Martynenko, F. A.; Sorokin, V. V.
2017-12-01
On the basis of quasipotential method in quantum electrodynamics we calculate nuclear finite size radiative corrections of order α(Zα) 5 to the Lamb shift in muonic hydrogen and helium. To construct the interaction potential of particles, which gives the necessary contributions to the energy spectrum, we use the method of projection operators to states with a definite spin. Separate analytic expressions for the contributions of the muon self-energy, the muon vertex operator and the amplitude with spanning photon are obtained. We present also numerical results for these contributions using modern experimental data on the electromagnetic form factors of light nuclei.
Up-down quark mass difference effect in nuclear many-body systems
International Nuclear Information System (INIS)
Nakamura, S.; Muto, K.; Oka, M.; Takeuchi, S.; Oda, T.
1995-01-01
A charge-symmetry-breaking nucleon-nucleon force due to the up-down quark mass difference is evaluated in the quark cluster model. It is applied to the shell-model calculation for the isovector mass shifts of isospin multiplets and the isospin-mixing matrix elements in 1s0d-shell nuclei. We find that the contribution of the quark mass difference effect is large and agrees with experiment. This contribution may explain the Okamoto-Nolen-Schiffer anomaly, alternatively to the meson-mixing contribution, which is recently predicted to be reduced by the large off-shell correction. (author)
Up-down quark mass difference effect in nuclear many-body systems
International Nuclear Information System (INIS)
Nakamura, S.; Muto, K.; Oka, M.; Takeuchi, S.; Oda, T.
1996-01-01
A charge-symmetry-breaking nucleon-nucleon force due to the up-down quark mass difference is evaluated in the quark cluster model. It is applied to the shell-model calculation for the isovector mass shifts of isospin multiplets in 1s0d-shell nuclei. We find that the contribution of the quark mass difference effect explains the systematic behavior of experiment. This contribution is large and may explain the Okamoto-Nolen-Schiffer anomaly, alternatively to the meson-mixing contribution, which is recently predicted to be reduced by the large off-shell correction. copyright 1996 The American Physical Society
Mass estimation of loose parts in nuclear power plant based on multiple regression
International Nuclear Information System (INIS)
He, Yuanfeng; Cao, Yanlong; Yang, Jiangxin; Gan, Chunbiao
2012-01-01
According to the application of the Hilbert–Huang transform to the non-stationary signal and the relation between the mass of loose parts in nuclear power plant and corresponding frequency content, a new method for loose part mass estimation based on the marginal Hilbert–Huang spectrum (MHS) and multiple regression is proposed in this paper. The frequency spectrum of a loose part in a nuclear power plant can be expressed by the MHS. The multiple regression model that is constructed by the MHS feature of the impact signals for mass estimation is used to predict the unknown masses of a loose part. A simulated experiment verified that the method is feasible and the errors of the results are acceptable. (paper)
International Nuclear Information System (INIS)
Torikai, Seishi; Ozawa, Michihiro; Kanegae, Naomichi; Tani, Masaaki; Miyakoshi, Naoki; Madarame, Haruki
2010-01-01
On March 30, 2007, Japan's electric utilities reported the results of a complete review of their powergenerating units to the Nuclear and Industrial Safety Agency of the Ministry of Economy, Trade, and Industry (METI). The Ethics Committee of the Atomic Energy Society of Japan (AESJ) then recommended an assessment method to analyze the seriousness of the problems from multiple perspectives in order to support the public's understanding of the reported problems. Accordingly, the Ethics Committee conducted the assessment. The assessment considered each reported problem associated with nuclear power-generating units and the preventive measures completed between June 2007 and September 2008 (corrective measures continued beyond that period). The results were presented at the autumn conferences of AESJ in 2007 and 2008, and are discussed in this report. (author)
American Society for Testing and Materials. Philadelphia
2010-01-01
1.1 These test methods cover procedures for the chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade plutonium nitrate solutions to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Plutonium by Controlled-Potential Coulometry Plutonium by Amperometric Titration with Iron(II) Plutonium by Diode Array Spectrophotometry Free Acid by Titration in an Oxalate Solution 8 to 15 Free Acid by Iodate Precipitation-Potentiometric Titration Test Method 16 to 22 Uranium by Arsenazo I Spectrophotometric Test Method 23 to 33 Thorium by Thorin Spectrophotometric Test Method 34 to 42 Iron by 1,10-Phenanthroline Spectrophotometric Test Method 43 to 50 Impurities by ICP-AES Chloride by Thiocyanate Spectrophotometric Test Method 51 to 58 Fluoride by Distillation-Spectrophotometric Test Method 59 to 66 Sulfate by Barium Sulfate Turbidimetric Test Method 67 to 74 Isotopic Composition by Mass Spectrom...
Ablation and deceleration of mass-driver launched projectiles for space disposal of nuclear wastes
International Nuclear Information System (INIS)
Park, C.; Bowen, S.W.
1981-01-01
The energy cost of launching a projectile containing nuclear waste is two orders of magnitude lower with a mass driver than with a typical rocket system. A mass driver scheme will be feasible, however, only if ablation and deceleration are within certain tolerable limits. It is shown that if a hemisphere-cylinder-shaped projectile protected thermally with a graphite nose is launched vertically to attain a velocity of 17 km/sec at an altitude of 40 km, the mass loss from ablation during atmospheric flight will be less than 0.1 ton, provided the radius of the projectile is under 20 cm and the projectile's mass is of the order of 1 ton. The velocity loss from drag will vary from 0.4 to 30 km/sec, depending on the mass and radius of the projectile, the smaller velocity loss corresponding to large mass and small radius. Ablation is always within a tolerable range for schemes using a mass driver launcher to dispose of nuclear wastes outside the solar system. Deceleration can also be held in the tolerable range if the mass and diameter of the projectile are properly chosen
International Nuclear Information System (INIS)
Wernli, Beath; Guenther-Leopold, Ines; Kobler Waldis, Judith; Kopajtic, Zlatan
2003-01-01
The characterisation of nuclear fuel cycle materials for trace and minor metallic constituents is of great interest for the nuclear industry and safeguard officials. The main objective of various international programmes dealing with postirradiation examinations is to improve the knowledge of the inventories of actinides, fission and spallation products in spent nuclear fuels. The low detection limits for a large number of elements combined with the ability to analyse the isotopic composition of the elements have established inductively coupled plasma mass spectrometry (ICP-MS) as a powerful multi-element technique in diverse analytical applications for the characterisation of nuclear materials. Because numerous isobaric overlaps restrict the direct determination of many fission products by mass spectrometry, extensive chemical separations are required for these elements. In order to simplify this sample preparation procedure, a high performance liquid chromatography system (HPLC) was online coupled to the mass spectrometer. Since about 10 years a quadrupole based ICP-MS (Q-ICP-MS) combined with an HPLC is used within the Hot Laboratory of the Paul Scherrer Institut for different applications on nuclear fuel samples. Since May 2003 also a new multi-collector ICP-MS (MC-ICP-MS) is used for the mass spectrometric characterisation of nuclear fuel samples, especially for the precise determination of the isotopic vectors of fission products and actinides. Therefore, two complementary analytical systems are now available in the group of 'Isotope and Wet Analytical Chemistry'. A comparison of the analytical performance of both systems (with and without an online coupled HPLC system) for the determination of the isotopic composition and the elemental concentration of different nuclides in nuclear fuel samples, the advantages and limitations of both techniques, the accuracy and precision of the results and typical applications for both methods will be discussed in the
International Nuclear Information System (INIS)
2003-01-01
The Centre for nuclear and mass spectroscopy (CSNSM) is a CNRS (National Centre for Scientific Research) laboratory affiliated with Paris-Sud University. The CSNSM is involved in pluri-disciplinary activities covering various scientific domains: Nuclear Structure (SNO), Nuclear Astrophysics (AN), Solid State Astrophysics (AS), Solid State Physics (PS) and Chemical Physics of Irradiation. This document presents the activity of the Centre during the 1985-1986-1987 years: 1 - Teams presentation; 2 - Abstracts: On the borderline of spectroscopy; Atomic spectroscopy and low-energy low-spin nuclear structure; high-energy high-spin nuclear structure; Theories and models; Nuclear astrophysics; Accelerator-based mass spectroscopy; Solid State Physics; Study of charged particles irradiation effects in astrophysics, geophysics and material sciences; Technical developments for the RF mass spectrometer and for Obelix; Technical developments for ion beams; Technical developments in electronics and their applications; CNSM's Computer Department; Developments in cryogenics; 3 - Staff and publications
International Nuclear Information System (INIS)
Dakshinamoorthy, A.
2007-01-01
Mass spectrometry finds the widespread application in nuclear science and technology due to the fact that it can be employed for isotope composition measurements of different elements of interest and also concentration measurements of these elements using isotope dilution techniques. Thermal ionization mass spectrometer (TIMS), Inductively coupled plasma mass spectrometer (ICP-MS) and gas chromatography mass spectrometer (GC-MS) are the different types of mass spectrometers used in nuclear industry for the analyses of isotope composition of special nuclear material, trace impurities in nuclear fuels and components and characterization of various solvents respectively. Among them, TIMS plays a vital role in the nuclear fuel cycle in determining precisely the isotope composition of uranium, plutonium, D/H ratio in heavy water etc. TIMS is an indispensable analytical tool for nuclear material accounting at the input stage of a reprocessing plant by carrying out precise and accurate concentration measurement of plutonium and uranium by isotope dilution mass spectrometry (IDMS). It is the only accepted measurement technique for the purpose because of its high precision, better sensitivity and no quantitative separation is needed. The isotope abundance measurements of uranium and plutonium at this point are also useful for burn-up studies and isotope correlations. Mass spectrometric analysis of uranium and plutonium is also required for nuclear data measurements and calibrating other chemical methods
The Nuclear Finite–Size Corrections to Energies of n = 1, n = 2 AND ...
African Journals Online (AJOL)
Results show that as the energy levels increases, the effects of the finite – size nucleus on the ... This gives us more information on the nuclear charge distribution. ... Hamiltonian; wave function; nucleus; point-size; finite–size; potential energy ...
Verification of the Correctness and Completeness of Nuclear Operators' Declarations by Euratom
International Nuclear Information System (INIS)
Meylemans, P.; Szymanski, P.; Synetos, S.; Beuseling, P.; Jirsa, P.; Ciccarello, S.; Kilb, W.; Klumpp, P.; Schwalbach, P.; Schoop, K.; Koutsoyannopoulos, C.; Lahogue, Y.; Persson, L.; Coadou, J.; Koehne, W.; Kahnmeyer, W.; Dratschmidt, H.; Thomas, M.; Lahogue-Incerti, M.; )
2015-01-01
We present the Euratom nuclear safeguards system, a supranational system used to verify the operators' and States' (when required by the Additional Protocol) declarations. The verifications performed by the European Commission serve to conclude on the nondiversion of the civil stocks of nuclear materials in the territories of EU Member States (Article 77a Euratom Treaty) and to fulfil obligations stemming from nuclear cooperation agreements with third States and international organizations such as the IAEA (Article 77b). In line with multilateral safeguards agreements and their respective additional protocols, as well as under the New Partnership Approach, Euratom works closely with the IAEA in order to avoid unnecessary duplication of efforts while maintaining the ability of both organizations to reach independent conclusions. In our paper the focus lies on the verifications performed before transmitting data to the IAEA. Starting from the sheer volume of data we describe checks and other operations performed (e.g., format adaptations) on the nuclear material accountancy (NMAC) data and Additional Protocol declarations; including quality assurance measures. We also present some statistics on the related workload, including answering queries from the IAEA. We describe the IT tools developed by Euratom for nuclear operators to submit their declarations and which are subsequently verified by Euratom before being transmitted to the IAEA. Moreover, we present support activities aiming at improving the operators' NMAC systems such as audits (including audits of measurement systems). We conclude by presenting the challenges lying ahead and ways to address them to further strengthen and improve the quality of the Euratom work and cooperation with the IAEA. (author)
Administrative Procedure Act and mass procedures (illustrated by the nuclear licensing procedure)
International Nuclear Information System (INIS)
Naumann, R.
1977-01-01
The report deals with the administrative procedure law of 25.5.76 of the Fed. Government, esp. with its meaning for the administrative procedures for the permission for nuclear power plants, as fas ar so-called mass procedures are concerned. (UN) [de
Uniformity measure for power-law mass spectrum in nuclear fragmentation
International Nuclear Information System (INIS)
Wislicki, W.
1992-11-01
Description is given in terms of the Renyi entropy and the uniformity for the canonical ensemble, the grand canonical ensemble and the power-law probability measures. The study is presented of the power-law spectra of cluster masses observed in nuclear interactions in the vicinity of the liquid-gas transition point. 6 figs., 1 tab., 15 refs. (author)
Onsets of nuclear deformation from measurements with the Isoltrap mass spectrometer
Naimi, Sarah
Mass measurements provide important information concerning nuclear structure. This work presents results from the pioneering Penning trap spectrometer ISOLTRAP at CERN-ISOLDE. High-precision mass measurements of neutron-rich manganese ($^{58−66}$Mn) and krypton isotopes ($^{96,97}$Kr) are presented, of which the $^{66}$Mn and $^{96,97}$Kr masses are measured for the first time. In particular, the mass of $^{97}$Kr was measured using the preparation trap and required the definition of a new fit function. In the case of the manganese isotopes, the N = 40 shell closure is addressed. The two-neutron-separation energies calculated from the new masses show no shell closure at N = 40 but give an estimation of the proton-neutron interaction (around 0.5 MeV) responsible for the increase of collectivity and nuclear deformation in this mass region. The new krypton masses show behavior in sharp contrast with heavier neighbors where sudden and intense deformation is present, interpreted as the establishment of a nuclea...
Nuclear assay of coal. Volume 6. Mass flow devices for coal handling
International Nuclear Information System (INIS)
Anon.
1979-01-01
The mass of coal entering the boiler per unit time is an essential parameter for determinig the total rate of heat input. The mass flow rate of coal on a conveyor belt is generally determined as a product of the instantaneous mass of material on a short section of the belt and the belt velocity. Belt loading could be measured by conventional transducers incorporating mechanical or electromechanical weighers or by gamma-ray attenuation gauge. This report reviews the state of the art in mass flow devices for coal handling. The various methods are compared and commented upon. Special design issues are discussed relative to incorporating a mass flow measuring device in a Continuous On-Line Nuclear Analysis of Coal (CONAC) system
Nuclear assay of coal. Volume 6. Mass flow devices for coal handling. Final report
International Nuclear Information System (INIS)
Gozani, T.; Elias, E.; Bevan, R.
1980-04-01
The mass of coal entering the boiler per unit time is an essential parameter for determining the total rate of heat input. The mass flow rate of coal on a conveyor belt is generally determined as a product of the instantaneous mass of material on a short section of the belt and the belt velocity. Belt loading could be measured by conventional transducers incorporating mechanical or electromechanical weighers or by gamma-ray attenuation gauge. This report reviews the state of the art in mass flow devices for coal handling. The various methods are compared and commented upon. Special design issues are discussed relative to incorporating a mass flow measuring device in a Continuous On-Line Nuclear Analysis of Coal (CONAC) system
Atomic mass and characteristic constant of nuclear ground state (CENPL.MCC). Pt. 1
International Nuclear Information System (INIS)
Su Zongdi; Ma Lizhen; Zhou Chunmei; Ge Zhigang
1994-01-01
Atomic mass and characteristic constants for nuclear ground states are basic data for nuclear physics, and necessary ones for basic researches, theoretical calculations, as well as many applied researches. The atomic mass of exotic nuclei quite far from the valley stability are also very important for astrophysics researches. The above-requirement is paid attention to in our setting up this file. The recent and as many as possible data (such as the half-lives of the new nuclides 202 Pt, 208 Hg and 185 Hf and the mass excess of 199 Ir, which were produced and distinguished by Chinese scientists) have been collected, and put into the computer-based data file in brief table format. (1 fig.)
The impact of global nuclear mass model uncertainties on r-process abundance predictions
Directory of Open Access Journals (Sweden)
Mumpower M.
2015-01-01
Full Text Available Rapid neutron capture or ‘r-process’ nucleosynthesis may be responsible for half the production of heavy elements above iron on the periodic table. Masses are one of the most important nuclear physics ingredients that go into calculations of r-process nucleosynthesis as they enter into the calculations of reaction rates, decay rates, branching ratios and Q-values. We explore the impact of uncertainties in three nuclear mass models on r-process abundances by performing global monte carlo simulations. We show that root-mean-square (rms errors of current mass models are large so that current r-process predictions are insufficient in predicting features found in solar residuals and in r-process enhanced metal poor stars. We conclude that the reduction of global rms errors below 100 keV will allow for more robust r-process predictions.
International Nuclear Information System (INIS)
Carrascosa Fernandez, C. B.; Gil Agudo, A.; Rodriguez Exodo, J. M.; Torres Donaire, J.; Zapata jimenez, J. C.; Arjona Gutierrez, J.
2011-01-01
One of the functions of a Service of Radio physics and Radiation Protection is the quality control of equipment emitting ionizing radiation and detectors for clinical use and verification to incidents and actions of the commercial house that could affect the dose or the quality image. The following is the procedure used in our hospital to track incidents that cause teams in Radiology (DR), Nuclear Medicine (MN) and Radiation Oncology (ONRT) in collaboration with the Electro medicine Service (EM .).
Feng, Wei; Lemoine, Jean-Michel; Zhong, Min; Xu, Houze
2014-05-01
An annual amplitude of ~18 cm mass-induced sea level variations (SLV) in the Red Sea is detected from steric-corrected altimetry and the Gravity Recovery and Climate Experiment (GRACE) satellites from 2003 to 2011, which dominates the mean sea level in the region. Seawater mass variations here generally reach maximum in late January/early February. The steric component of SLV calculated from oceanographic temperature and salinity data is relatively small and peaks about seven months later than mass variations. The phase difference between the steric SLV and the mass-induced SLV indicates that when the Red Sea gains the mass from inflow water in winter, the steric SLV fall, and vice versa in summer. In-situ bottom pressure records in the eastern coast of the Red Sea validate the high mass variability observed by steric-corrected altimetry and GRACE. Furthermore, we compare the horizontal water mass flux in the Red Sea from steric-corrected altimetry and GRACE with that estimated from hydrographic observations.
Application of environmentally-corrected fatigue curves to nuclear power plant components
International Nuclear Information System (INIS)
Ware, A.G.; Morton, D.K.; Nitzel, M.E.
1996-01-01
Recent test data indicate that the effects of the light water reactor (LWR) environment could significantly reduce the fatigue resistance of materials used in the reactor coolant pressure boundary components of operating nuclear power plants. Argonne National Laboratory has developed interim fatigue curves based on test data simulating LWR conditions, and published them in NUREG/CR-5999. In order to assess the significance of these interim fatigue curves, fatigue evaluations of a sample of the components in the reactor coolant pressure boundary of LWRs were performed. The sample consists of components from facilities designed by each of the four US nuclear steam supply system vendors. For each facility, six locations were studied including two locations on the reactor pressure vessel. In addition, there are older vintage plants where components of the reactor coolant pressure boundary were designed to codes that did not require an explicit fatigue analysis of the components. In order to assess the fatigue resistance of the older vintage plants, an evaluation was also conducted on selected components of three of these plants. This paper discusses the insights gained from the application of the interim fatigue curves to components of seven operating nuclear power plants
Finite size and Coulomb corrections: from nuclei to nuclear liquid vapor phase diagram
International Nuclear Information System (INIS)
Moretto, L.G.; Elliott, J.B.; Phair, L.
2003-01-01
In this paper we consider the problem of obtaining the infinite symmetric uncharged nuclear matter phase diagram from a thermal nuclear reaction. In the first part we shall consider the Coulomb interaction which, because of its long range makes the definition of phases problematic. This Coulomb effect seems truly devastating since it does not allow one to define nuclear phase transitions much above A ∼ 30. However there may be a solution to this difficulty. If we consider the emission of particles with a sizable charge, we notice that a large Coulomb barrier Bc is present. For T << Bc these channels may be considered effectively closed. Consequently the unbound channels may not play a role on a suitably short time scale. Then a phase transition may still be definable in an approximate way. In the second part of the article we shall deal with the finite size problem by means of a new method, the complement method, which shall permit a straightforward extrapolation to the infinite system. The complement approach consists of evaluating the change in free energy occurring when a particle or cluster is moved from one (finite) phase to another. In the case of a liquid drop in equilibrium with its vapor, this is done by extracting a vapor particle of any given size from the drop and evaluating the energy and entropy changes associated with both the vapor particle and the residual liquid drop (complement)
Directory of Open Access Journals (Sweden)
Sang-Wook Jin
2017-01-01
Full Text Available One of the most important issues in keeping membrane structures in stable condition is to maintain the proper stress distribution over the membrane. However, it is difficult to determine the quantitative real stress level in the membrane after the completion of the structure. The stress relaxation phenomenon of the membrane and the fluttering effect due to strong wind or ponding caused by precipitation may cause severe damage to the membrane structure itself. Therefore, it is very important to know the magnitude of the existing stress in membrane structures for their maintenance. The authors have proposed a new method for separately estimating the membrane stress in two different directions using sound waves instead of directly measuring the membrane stress. The new method utilizes the resonance phenomenon of the membrane, which is induced by sound excitations given through an audio speaker. During such experiment, the effect of the surrounding air on the vibrating membrane cannot be overlooked in order to assure high measurement precision. In this paper, an evaluation scheme for the added mass of membrane with the effect of air on the vibrating membrane and the correction of measurement error is discussed. In addition, three types of membrane materials are used in the experiment in order to verify the expandability and accuracy of the membrane measurement equipment.
International Nuclear Information System (INIS)
2005-01-01
The Centre for nuclear and mass spectroscopy (CSNSM) is a CNRS (National Centre for Scientific Research) laboratory affiliated with Paris-Sud University. The CSNSM is involved in pluri-disciplinary activities covering various scientific domains: Nuclear Structure (SNO), Nuclear Astrophysics (AN), Solid State Astrophysics (AS), Solid State Physics (PS) and Chemical Physics of Irradiation. This document presents the activity of the Centre during the 2002-2004 years: 1 - Foreword; 2 - Nuclear structure; 3 - EFIX: study of exotic nuclei-induced fission; 4 - Nuclear Astrophysics; 5 - Atomic mass; 6 - Solid state astrophysics; 7 - Accelerator-based mass spectroscopy; 8 - Solid State Physics; 9 - Physics and Chemistry of Irradiation; 10 - Activities of general interest; 11 - SEMIRAMIS (ion source and ion beam handling); 12 - Computer Department; 13 - Electronics Group; 14 - Mechanics Department; 15 - Health and safety; 16 - Permanent training; 17 - Seminars; 18 - PhDs; 19 - Staff
RSMASS-D nuclear thermal propulsion and bimodal system mass models
King, Donald B.; Marshall, Albert C.
1997-01-01
Two relatively simple models have been developed to estimate reactor, radiation shield, and balance of system masses for a particle bed reactor (PBR) nuclear thermal propulsion concept and a cermet-core power and propulsion (bimodal) concept. The approach was based on the methodology developed for the RSMASS-D models. The RSMASS-D approach for the reactor and shield sub-systems uses a combination of simple equations derived from reactor physics and other fundamental considerations along with tabulations of data from more detailed neutron and gamma transport theory computations. Relatively simple models are used to estimate the masses of other subsystem components of the nuclear propulsion and bimodal systems. Other subsystem components include instrumentation and control (I&C), boom, safety systems, radiator, thermoelectrics, heat pipes, and nozzle. The user of these models can vary basic design parameters within an allowed range to achieve a parameter choice which yields a minimum mass for the operational conditions of interest. Estimated system masses are presented for a range of reactor power levels for propulsion for the PBR propulsion concept and for both electrical power and propulsion for the cermet-core bimodal concept. The estimated reactor system masses agree with mass predictions from detailed calculations with xx percent for both models.
DOE's efforts to correct environmental problems of the nuclear weapons complex
International Nuclear Information System (INIS)
Rezendes, V.S.
1990-03-01
This report focuses on four main issues: the environmental problems at DOE's nuclear weapons complex, recent changes in DOE's organizational structure, DOE's 1991 budget request, and the need for effective management systems. This report concludes that the environmental problems are enormous and will take decades to resolve. Widespread contamination can be found at many DOE sites, and the full extent of the environmental problems is unknown. DOE has taken several steps during the past year to better deal with these problems, including making organizational improvements and requesting additional funds for environmental restoration and waste management activities
International Nuclear Information System (INIS)
Su Zongdi; Ma Lizhen
1994-01-01
The management code of the sub-library of atomic mass and characteristic constants for nuclear ground state (MCC) is used for displaying the basic information on the MCC sub-library on the screen, and retrieving the required data. The MCC data file contains the data of 4800 nuclides ranging from Z 0, A = 1 to Z = 122, A = 318. The MCC sub-library has been set up at Chinese Nuclear Data Center (CNDC), and has been used to provide the atomic masses and characteristic constants of nuclear ground states for the nuclear model calculation, nuclear data evaluations and other fields
Time for nuclear to be set free from shackles of political correctness
Energy Technology Data Exchange (ETDEWEB)
Shepherd, John [nuclear 24, St. Georges Redditch (United Kingdom)
2017-01-15
Towards the end of 2016, a milestone report from the International Energy Agency (IEA) set out what were described as the ''frontlines for additional emissions reductions'' in the global power sector in the years ahead. The tools for continuing efforts to rein in emissions and combat climate change include, according to the IEA's World Energy Outlook 2016, the ''accelerated deployment'' of renewables, carbon capture and storage, a ''strong push'' for greater electrification and efficiency across all end-uses and ''a robust and concerted'' clean energy research and development effort by governments and companies. Nuclear power was also included in the publication as one of the ways that countries could reduce emissions harmful to our planet.. although the IEA's report said nuclear's role would depend on it being ''politically acceptable''.
International Nuclear Information System (INIS)
Thierry, Raphael
1999-01-01
Multi-photonic emission tomography is a non destructive technique applied to the control of radioactive waste drums. The emitted gamma rays are detected on the range [50 keV, 2 MeV] by a hyper pure germanium, of high resolution in energy, which enables to set up a detailed list of radionuclides contained within the drum. From different points of measurement located in a transaxial plane of the drum, the activity distribution is computed by a reconstruction algorithm. An algebraic modelling of the physical process has been developed in order to correct the different degrading phenomenon, in particular the attenuation and the detector geometric response. Attenuation through the materials constituting the barrel is the preponderant phenomena. Its ignorance prevents from accurate activity quantification. Its correction has been realised from an attenuation map obtained by a transmission tomograph. The detector geometric response, introducing a blurring within the detection, is compensated by an analytic model. An adequate modelling of those phenomenon is primordial: it highly contributes on a large scale the image quality and the quantification. The image reconstruction, requiring the resolution of sparse linear system, is realised by iterative algorithms. Due to the 'ill-posed' nature of tomographic reconstruction, it is necessary to use regularisation: by introducing an a priori information on the solution, the stabilisation of the methods is carried out. We chose to minimise the Maximum A Posteriori criterion. Its resolution is considered with a half-quadratic regularisation: it permits the preservation of natural discontinuities, and avoids global-over smoothing of the image. It is evaluated on real phantoms and waste drums. Efficient sampling of the data is considered. (author) [fr
International Nuclear Information System (INIS)
Jeon, Young Sin; Pyo, Hyeong Yeol; Park, Yong Joon; Song, Kyu Seok; Kim, Won Ho; Jee, Kwang Yong
2007-05-01
It is very important to develope the technology for the determination of isotopic ratios of hot particles( 234 U, 235 U, 236 U etc.) detected from swipe samples of various nuclear facilities. This technology is highly competitive internationally and has to be established independently as long as our government maintains atomic energy and treats nuclear materials. In this text, sample pretreatment procedure, gamma-ray counting, alpha or fission track techniques, isotopic analysis of U and Pu, background problems and detection limits for mass determination, and their application to the real swipe sample were described with detailed procedure. This technology would contribute to the Korean economy's high growth rate as well as to superiority of government's leading research and development programs if successfully established
American Society for Testing and Materials. Philadelphia
1999-01-01
1.1 These test methods cover procedures for the chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade uranyl nitrate solution to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Determination of Uranium 7 Specific Gravity by Pycnometry 15-20 Free Acid by Oxalate Complexation 21-27 Determination of Thorium 28 Determination of Chromium 29 Determination of Molybdenum 30 Halogens Separation by Steam Distillation 31-35 Fluoride by Specific Ion Electrode 36-42 Halogen Distillate Analysis: Chloride, Bromide, and Iodide by Amperometric Microtitrimetry 43 Determination of Chloride and Bromide 44 Determination of Sulfur by X-Ray Fluorescence 45 Sulfate Sulfur by (Photometric) Turbidimetry 46 Phosphorus by the Molybdenum Blue (Photometric) Method 54-61 Silicon by the Molybdenum Blue (Photometric) Method 62-69 Carbon by Persulfate Oxidation-Acid Titrimetry 70 Conversion to U3O8 71-74 Boron by ...
Importance of banked tissues in the management of mass nuclear casualties
International Nuclear Information System (INIS)
Singh, Rita; Bhatnagar, P.K.
2009-01-01
Nuclear detonations are the most devastating of the weapons of mass destruction. There will be large number of casualties on detonation of nuclear weapon. Biological tissues like bone, skin, amniotic membrane and other soft tissues can be used for repair or reconstruction of the injured part of the body. Tissues from human donor can be processed and banked for orthopaedic, spinal, trauma and other surgical procedures. Radiation technology is used to sterilize the tissues to make them safe for clinical use. This paper highlights the importance of such banked tissues in the management of the casualties. (author)
Effective mass of a #betta#-particle in nuclear matter and OBE #betta#-n interactions
International Nuclear Information System (INIS)
Bando, Hiroharu; Nagata, Sinobu.
1982-01-01
The effective mass of a lambda particle (M sub( lambda )*) in nuclear matter is investigated within the framework of the lowest-order Brueckner theory by employing the Nijmegen OBE lambda -N interaction model D and F. The non-locality mass (M tilde sub( lamda )) and the energy mass (anti M sub( lambda )) are evaluated and discussed in the light of the characteristics of the two models. In comparison with the model D, the model F yields smaller anti M sub( lambda ) and larger anti M sub( lamb da ) reflecting the stronger Majorana exchange force and the stronger lambda N- sigma N coupling tensor force. Final results of M sub( lambda )*/M sub( lambda ) are 0.85 for D and 0.79 for F. In view of the effective lambda mass inferred from observed properties of the single particle potential for lambda , the model D interaction seems to be more adequate. (author)
International Nuclear Information System (INIS)
Hajek, B.K.; Stasenko, J.E.; Hashemi, S.; Bhatnagar, R.; Yamada, N.; Punch, W.F. III.
1987-01-01
Two prototype knowledge based systems have been developed at the Ohio State University. These systems were the result of collaboration between the Nuclear Engineering Program and the Laboratory for Artificial Intelligence Research (LAIR). The first system uses hierarchical classification to diagnose malfunctions of the coolant system in a General Electric Boiling Water Reactor (BWR). The second system provides a plan of action, through a process of dynamic procedure synthesis, to stabilize the plant once an abnormal transient has occurred. The objective of this paper is to discuss a structure that will integrate the two systems. The combined system will be capable of informing plant personnel about the nature of malfunctions, and of supplying to the operator the most direct corrective procedure available. Two important features of the integrated system are faulty sensor detection, based on malfunction context and unlike sensor data, and procedure synthesis based on the initial state of the plant
Energy Technology Data Exchange (ETDEWEB)
Moore, Murray E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reeves, Kirk Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2015-02-24
Two LANL FTS (Filter Test System ) devices for nuclear material storage canisters are fully operational. One is located in PF-4 ( i.e. the TA-55 FTS) while the other is located at the Radiation Protection Division’s Aerosol Engineering Facility ( i.e. the TA-3 FTS). The systems are functionally equivalent , with the TA-3 FTS being the test-bed for new additions and for resolving any issues found in the TA-55 FTS. There is currently one unresolved issue regarding the TA-55 FTS device. The canister lid clamp does not give a leak tight seal when testing the 1 QT (quart) or 2 QT SAVY lids. An adapter plate is being developed that will ensure a correct test configuration when the 1 or 2 QT SAVY lid s are being tested .
On the two-loop corrections to the pole mass of the B quark in the gaugeless limit of the MSSM
International Nuclear Information System (INIS)
Bednyakov, A.V.; Kazakov, D.I.; )
2007-01-01
The result for the two-loop corrections to the pole mass of the b quark in the gaugeless limit of the MSSM is presented. In this limit it is assumed that the contribution from the electroweak gauge interactions is small. The result presented here differs from one obtained earlier, especially in some particular regions of the MSSM parameter space [ru
Mass and Elite Views on Nuclear Security: US National Security Surveys 1993-1999
Energy Technology Data Exchange (ETDEWEB)
HERRON,KERRY G.; JENKINS-SMITH,HANK C.; HUGHES,SCOTT D.
2000-06-01
This is the fourth report in an ongoing series of studies examining how US perspectives about nuclear security are evolving in the post-Cold War era. In Volume 1 the authors present findings from a nationwide telephone survey of randomly selected members of the US general public conducted from 13 September to 14 October 1999. Results are compared to findings from previous surveys in this series conducted in 1993, 1995, and 1997, and trends are analyzed. Key areas of investigation reported in Volume 1 include evolving perceptions of nuclear weapons risks and benefits, preferences for related policy and spending issues, and views about three emerging issue areas: deterrent utility of precision guided munitions; response options to attacks in which mass casualty weapons are used; and expectations about national missile defenses. In this volume they relate respondent beliefs about nuclear security to perceptions of nuclear risks and benefits and to policy preferences. They develop causal models to partially explain key preferences, and they employ cluster analysis to group respondents into four policy relevant clusters characterized by similar views and preferences about nuclear security within each cluster. Systematic links are found among respondent demographic characteristics, perceptions of nuclear risks and benefits, policy beliefs, and security policy and spending preferences. In Volume 2 they provide analysis of in-depth interviews with fifty members of the US security policy community.
Mass and Elite Views on Nuclear Security: US National Security Surveys 1993-1999
International Nuclear Information System (INIS)
Herron, Kerry G.; Jenkins-Smith, Hank C.; Hughes, Scott D.
2000-01-01
This is the fourth report in an ongoing series of studies examining how US perspectives about nuclear security are evolving in the post-Cold War era. In Volume 1 the authors present findings from a nationwide telephone survey of randomly selected members of the US general public conducted from 13 September to 14 October 1999. Results are compared to findings from previous surveys in this series conducted in 1993, 1995, and 1997, and trends are analyzed. Key areas of investigation reported in Volume 1 include evolving perceptions of nuclear weapons risks and benefits, preferences for related policy and spending issues, and views about three emerging issue areas: deterrent utility of precision guided munitions; response options to attacks in which mass casualty weapons are used; and expectations about national missile defenses. In this volume they relate respondent beliefs about nuclear security to perceptions of nuclear risks and benefits and to policy preferences. They develop causal models to partially explain key preferences, and they employ cluster analysis to group respondents into four policy relevant clusters characterized by similar views and preferences about nuclear security within each cluster. Systematic links are found among respondent demographic characteristics, perceptions of nuclear risks and benefits, policy beliefs, and security policy and spending preferences. In Volume 2 they provide analysis of in-depth interviews with fifty members of the US security policy community
DEFF Research Database (Denmark)
Niu, Yubiao; Schlexer, Philomena; Sebök, Béla
2018-01-01
with a reactive metal, Ti. Mass-selected Au/Ti clusters (400 000 amu) and Au2057 clusters (405 229 amu) were produced with a magnetron sputtering, gas condensation cluster beam source in conjunction with a lateral time-of-flight mass filter, deposited onto a silica support and characterised by XPS and LEIS....... The sintering dynamics of mass-selected Au and Au/Ti alloy nanoclusters were investigated in real space and real time with atomic resolution aberration-corrected HAADF-STEM imaging, supported by model DFT calculations. A strong anchoring effect was revealed in the case of the Au/Ti clusters, because of a much...
The nuclear flow and the mass number dependence of the balance point
International Nuclear Information System (INIS)
Sebille, F.; de la Mota, V.; Remaud, B.; Schuck, P.
1990-01-01
The nuclear flow is studied theoretically with the Landau Vlasov equation in the E/A = 50 to 150 MeV energy domain using the finite range Gogny force. For comparison also other equations of states based on velocity independent mean fields are used. In this paper the mass number dependence of the balance point is investigated. A sensitivity of the flow on the equation of state as a function of mass and energies around and above the balance point can tentatively be advanced
Double-arm time-of-flight mass-spectrometer of nuclear fragments
International Nuclear Information System (INIS)
Ajvazian, G.M.; Astabatyan, R.A.
1995-01-01
A double-arm time-of-flight spectrometer of nuclear fragments for the investigation of heavy nuclei photofission in the intermediate energy range is described. The calibration results and working characteristics of the spectrometer, obtained using 252 Cf as a source of spontaneous fission, are presented. A mass resolution of σ m ∼2-3 a.m.u. was obtained within the registered fragments mass range of 80-160 a.m.u. The spectrometer was tested in the experiment on the investigation of 238 U nuclei fission by Bremsstahlung photons with Eγ max=1.75 GeV
International Nuclear Information System (INIS)
Ducatti, C.; Salati, E.
1982-01-01
A review is made of analytical procedures to calculate correction factors, proposed by CRAIG (1957) to determine isotopic enrichment relating to the international PBD standard sample, obtained from analysis of carbon dioxide gas samples by mass spectrometry. Using such correction factors, the isotopic composition of the secondary CENA-standard sample is characterized through calculation of the main isotopic ratios of this sample. It is then possible to obtain correction factors for the determination of the isotopic enrichment relating to the secondary CENA-standard sample itself. New correction factors are proposed taking into account the interference of various isotopic species and the variability in sample and secondary standard preparation, that make possible the detemination of carbon-13 and oxygen-18 isotopic enrichment relating to the international PBD standard sample, with a total analytical error σ = + - 0.2 0 /00 in normal routine work. (Author) [pt
2010-03-01
Isotope Ratio Analysis of Actinides , Fission Products, and Geolocators by High- efficiency Multi-collector Thermal Ionization Mass Spectrometry...Information, 1999. Hou, Xiaolin, and Per Roos. “ Critical Comparison of radiometric and Mass Spectrometric Methods for the Determination of...NUCLEAR FORENSICS: MEASUREMENTS OF URANIUM OXIDES USING TIME-OF-FLIGHT SECONDARY ION MASS
Coupling of mass and charge distributions for low excited nuclear fission
International Nuclear Information System (INIS)
Salamatin, V.S.; )
2000-01-01
The simple model for calculation of charge distributions of fission fragments for low exited nuclear fission from experimental mass distributions is offered. The model contains two parameters, determining amplitude of even-odd effect of charge distributions and its dependence on excitation energy. Results for reactions 233 U(n th ,f), 235 U(n th ,f), 229 Th(n th ,f), 249 Cf(n th ,f) are spent [ru
Combating the terrorist use of mass destruction weapons, particularly nuclear weapons
International Nuclear Information System (INIS)
Barakat, M.
2008-01-01
The risks of mass destruction weapons vary and also forms of damages resulting therefrom. While the effects of nuclear weapons are focused, sudden and comprehensive, the chemical weapons have limited impacts relatively unless used intensively severe prejudice to the element of surprise, and thus impaired the efficacy of their influences,especially that they affect exceptionally the individuals in the area of injury and biological weapons do not announce themselves except through their effect that appears later than the time of use as they affect exceptionally the organisms in the area of injury.The mass destruction weapons have turned from being a purely military means in the early twentieth century and have now become the means of violence against governments and countries that they should prepare themselves for and respond in ways of successful and effective countermeasures. Despite the fact that the acquisition of mass destruction weapons can be considered as a priority objective, which terrorist groups and organizations steadily seek but their accessibility is flanked by a lot of difficulties. Addressing the risk of further spread of nuclear weapons, and especially after doubling the power of those high-risk weapons, the international community has an approach to take a number of arrangements that complement each other to control and resist nuclear proliferation, either for the states or for terrorist groups.
: Nuclear Spirals and Mass Accretion to Supermassive Black Holes in Weakly-Barred Galaxies
Kim, Woong-Tae; Elmegreen, Bruce
2018-01-01
Disk galaxies, especially barred-spiral galaxies, abound with rings and spirals in their nuclear regions. Nuclear spirals existing even in weakly barred galaxies are thought to channel gas inflows to supermassive black holes residing at the centers. We use high-resolution hydrodynamic simulations to study the properties of nuclear gas spirals driven by weak bar-like or oval potentials. The amplitude of the spirals increases toward the center by a geometric effect, readily developing into shocks at small radii even for very weak potentials. The shape of the spirals and shocks depends rather sensitively on the background shear. When shear is low, the nuclear spirals are loosely wound and the shocks are almost straight, resulting in large mass inflows toward the center. When shear is high, on the other hand, the spirals are tightly wound and the shocks are oblique, forming a circumnuclear disk through which gas flows inward at a relatively lower rate. The induced mass inflow rates are enough to power black hole accretion in various types of Seyfert galaxies.
International Nuclear Information System (INIS)
2003-01-01
The Centre for nuclear and mass spectroscopy (CSNSM) is a CNRS (National Centre for Scientific Research) laboratory affiliated with Paris-Sud University. The CSNSM is involved in pluri-disciplinary activities covering various scientific domains: Nuclear Structure (SNO), Nuclear Astrophysics (AN), Solid State Astrophysics (AS), Solid State Physics (PS) and Chemical Physics of Irradiation. This document presents the activity of the Centre during the 2001-2002 years: 1 - Foreword; 2 - Research topics: Nuclear structure; EFIX: study of exotic nuclei-induced fission; Nuclear Astrophysics; Accelerator-based mass spectroscopy; Solid State Astrophysics; Physics and Chemistry of Irradiation; Solid State Physics; SEMIRAMIS (ion source and ion beam handling); Digest science; 3 - Publications; 4 - Dissertations; 5 - Seminars; 6 - Technical services: Computer Department; Electronics Group; Mechanics Department; Permanent training; Health and safety; 7 - Staff
International Nuclear Information System (INIS)
2003-01-01
The Centre for nuclear and mass spectroscopy (CSNSM) is a CNRS (National Centre for Scientific Research) laboratory affiliated with Paris-Sud University. The CSNSM is involved in pluri-disciplinary activities covering various scientific domains: Nuclear Structure (SNO), Nuclear Astrophysics (AN), Solid State Astrophysics (AS), Solid State Physics (PS) and Chemical Physics of Irradiation. This document presents the activity of the Centre during the 1995-1997 years: 1 - Nuclear structure: structure of first well states, superdeformation, high-spin state populations of stable or neutron-rich nuclei, high-k isomers physics, theoretical works, technical developments; 2 - Nuclear astrophysics; 3 - Basic symmetries; 4 - Accelerator-based mass spectroscopy; 5 - Solid State Astrophysics; 6 - Physics and Chemistry of Irradiation; 7 - Solid State Physics; 8 - SEMIRAMIS (ion source and ion beam handling); 9 - Computer Department; 10 - Electronics Group; 11 - Mechanics Department; 12 - Permanent training; 13 - Health and safety; 14 - Seminars and communications; 15 - Dissertations; 16 - Publications; 17 - Staff
International Nuclear Information System (INIS)
2003-01-01
The Centre for nuclear and mass spectroscopy (CSNSM) is a CNRS (National Centre for Scientific Research) laboratory affiliated with Paris-Sud University. The CSNSM is involved in pluri-disciplinary activities covering various scientific domains: Nuclear Structure (SNO), Nuclear Astrophysics (AN), Solid State Astrophysics (AS), Solid State Physics (PS) and Chemical Physics of Irradiation. This document presents the activity of the Centre during the 1992-1994 years: 1 - Nuclear structure; 2 - Nuclear astrophysics; 3 - Basic symmetries; 4 - Accelerator-based mass spectroscopy; 5 - Solid State Astrophysics; 6 - Physics and Chemistry of Irradiation; 7 - Solid State Physics; 8 - SEMIRAMIS (ion source and ion beam handling); 9 - Computer Department; 10 - Electronics Group; 11 - Mechanics Department; 12 - Permanent training; 13 - Health and safety; 14 - Seminars; 15 - Dissertations; 16 - Publications; 17 - Staff
Energy Technology Data Exchange (ETDEWEB)
Rosenbusch, Marco [Ernst-Moritz-Arndt-Universitaet, Institut fuer Physik, 17487 Greifswald (Germany); Collaboration: ISOLTRAP-Collaboration
2013-07-01
The mass is a unique property of an atomic nucleus reflecting its binding energy and thus the sum of all interactions at work. Precise measurements of nuclear masses especially of short-lived exotic nuclides provide important input for nuclear structure, nuclear astrophysics, tests of the Standard Model, and weak interaction studies. The Penning-trap mass spectrometer ISOLTRAP at the on-line isotope separator ISOLDE/CERN has been set up for precision mass measurements and continuously improved for accessing more exotic nuclides. The mass uncertainty is typically δm / m=10{sup -8} and the accessible half-life has been reduced to about 50 ms. In this contribution, the results of a measurement campaign of neutron-rich francium and radium isotopes will be presented, i.e. the masses of the isotopic chain of {sup 224-233}Fr and {sup 233,234}Ra, one of the most neutron-rich ensemble obtainable at ISOL facilities. The mass {sup 234}Ra denotes the heaviest mass ever measured with ISOLTRAP. Experimental data in the neutron-rich, heavy mass region is of great interest for studies of structural evolution far from stability, especially because the knowledge from nuclear mass models is scarce. The impact of the new data on the physics in this mass region as well as recent technical developments of ISOLTRAP are discussed.
International Nuclear Information System (INIS)
Anon.
1981-01-01
These analytical procedures are designed to show whether a given material meets the purchaser's specifications as to plutonium content, effective fissile content, and impurity content. The following procedures are described in detail: plutonium by controlled-potential coulometry; plutonium by amperometric titration with iron(II); free acid by titration in an oxalate solution; free acid by iodate precipitation-potentiometric titration method; uranium by Arsenazo I spectrophotometric method; thorium by thorin spectrophotometric method; iron by 1,10-phenanthroline spectrophotometric method; chloride by thiocyanate spectrophotometric method; fluoride by distillation-spectrophotometric method; sulfate by barium sulfate turbidimetric method; isotopic composition by mass spectrometry; americium-241 by extraction and gamma counting; americium-241 by gamma counting; gamma-emitting fission products, uranium, and thorium by gamma-ray spectroscopy; rare earths by copper spark spectrochemical method; tungsten, niobium (columbium), and tantalum by spectrochemical method; simple preparation by spectrographic analysis for general impurities
Isotopic abundance measurements on solid nuclear-type samples by glow discharge mass spectrometry
International Nuclear Information System (INIS)
Betti, M.; Rasmussen, G.; Koch, L.
1996-01-01
A double-focusing glow discharge mass spectrometer (GDMS) installed in a glovebox for nuclear sample screening has been employed for isotopic measurements. Isotopic compositions of zirconium, silicon, lithium, boron, uranium and plutonium which are elements of nuclear concern have been determined. Interferences arising from the matrix sample and the discharge gas (Ar) for each of these elements are discussed. The GDMS results are compared with those from thermal ionization mass spectrometry (TIMS). For boron and lithium at μg/g-ng/g levels, the two methods gave results in good agreement. In samples containing uranium the isotopic composition obtained by GDMS was in agreement with those from TIMS independently of the enrichment. Attempts for the determination of plutonium isotopic composition were also made. In this case, due to the interferences of uranium at mass 238 and americium at mass 241, the GDMS raw data are complementary with those values obtained from physical non-destructive techniques. (orig.). With 2 figs., 4 tabs
Low-mass neutron stars: universal relations, the nuclear symmetry energy and gravitational radiation
O. Silva, Hector; Berti, Emanuele; Sotani, Hajime
2016-03-01
Compact objects such as neutron stars are ideal astrophysical laboratories to test our understanding of the fundamental interactions in the regime of supranuclear densities, unachievable by terrestrial experiments. Despite recent progress, the description of matter (i.e., the equation of state) at such densities is still debatable. This translates into uncertainties in the bulk properties of neutron stars, masses and radii for instance. Here we will consider low-mass neutron stars. Such stars are expected to carry important information on nuclear matter near the nuclear saturation point. It has recently been shown that the masses and surface redshifts of low-mass neutron stars smoothly depend on simple functions of the central density and of a characteristic parameter η associated with the choice of equation of state. Here we extend these results to slowly-rotating and tidally deformed stars and obtain empirical relations for various quantities, such as the moment of inertia, quadrupole moment and ellipticity, tidal and rotational Love numbers, and rotational apsidal constants. We discuss how these relations might be used to constrain the equation of state by future observations in the electromagnetic and gravitational-wave spectra.
Advertising campaigns on the necessity of nuclear energy through mass-media in Japan
International Nuclear Information System (INIS)
Niwano, Sadaji
1998-01-01
provide the public with materials and elements to think and decide with as information. In the background of those circumstances, the attitudes of PA activities toward the public-has changed recently to draw public attention to the wide range of issues from current severe energy conditions in Japan to global environmental problems connecting to the role and the position of nuclear power among overall national energy policies in Japan and let have urgent feelings among the public. Followings are the examples that we are taking up in promotion of advertising campaigns through mass media, including inter- net and other information tools. (1) To show concrete measures to be taken to meet national long- term energy supply/demand outlook for the year to 2030 that encourage energy- saving efforts, increased use of new energy sources and further development of nuclear power generation. (2) In this December, the 3rd Conference of the Parties to United Nations Framework Convention on Climate Change will be held at Kyoto, Japan. At this very moment that national attentions are increasingly concentrating toward the energy and environment issues, we will intend to hold advertising campaigns widely through mass media to heighten public awareness on the necessity of nuclear power promotion, as well as conservation and energy efficiency measures, introduction of alternative energy sources, such as solar, wind etc. in connection with the necessity of tackling the environmental problems, especially global warming phenomenon due to the greenhouse gas emissions. At this occasion, taking up some topics of specifically rapid energy demand which will obviously continue well into the next century and will very likely cause impending energy situations in Asian countries, expectations of serious environmental problems particularly in those of Asian countries, and among that appealing the role of nuclear energy as a clean energy source
Low mass dilepton production at the SPS probing hot and dense nuclear matter
Pérez de los Heros, C; Baur, R; Breskin, Amos; Chechik, R; Drees, A; Jacob, C; Faschingbauer, U; Fisher, P H; Fraenkel, Zeev; Fuchs, C; Gatti, E; Glässel, P; Günzel, T F; Hess, F; Irmscher, D; Lenkeit, B C; Olsen, L H; Panebratsev, Yu A; Pfeiffer, A; Ravinovich, I; Rehak, P; Schön, A; Schükraft, Jürgen; Sampietro, M; Shimansky, S S; Shor, A; Specht, H J; Steiner, V; Tapprogge, Stefan; Tel-Zur, G; Tserruya, Itzhak; Ullrich, T S; Wurm, J P; Yurevich, V I
1996-01-01
CERES and HELIOS-3 have detected a significant enhancement of low--mass dileptons in nuclear collisions at 200 GeV/nucleon with respect to the expected ``conventional'' sources. The onset of the excess, starting at a mass of $\\sim2m_{\\pi}$, and the possibility of a quadratic dependence on the event multiplicity suggest the opening of the $\\pi^+\\pi^-\\rightarrow e^+e^-(\\mu^+\\mu^-)$ annihilation channel. This would be the first observation of thermal radiation from dense hadronic matter. Possible interpretations of these results are presented, including the reduction of the $\\rho$ mass due to partial restoration of chiral symmetry in the dense fireball formed in the collision.
EFFECT OF CENTRAL MASS CONCENTRATION ON THE FORMATION OF NUCLEAR SPIRALS IN BARRED GALAXIES
International Nuclear Information System (INIS)
Thakur, Parijat; Jiang, I.-G.; Ann, H. B.
2009-01-01
We have performed smoothed particle hydrodynamics simulations to study the response of the central kiloparsec region of a gaseous disk to the imposition of nonaxisymmetric bar potentials. The model galaxies are composed of three axisymmetric components (halo, disk, and bulge) and a nonaxisymmetric bar. These components are assumed to be invariant in time in the frame corotating with the bar. The potential of spherical γ-models of Dehnen is adopted for the bulge component whose density varies as r -γ near the center and r -4 at larger radii and, hence, possesses a central density core for γ = 0 and cusps for γ>0. Since the central mass concentration of the model galaxies increases with the cusp parameter γ, we have examined here the effect of the central mass concentration by varying the cusp parameter γ on the mechanism responsible for the formation of the symmetric two-armed nuclear spirals in barred galaxies. Our simulations show that the symmetric two-armed nuclear spirals are formed by hydrodynamic spiral shocks driven by the gravitational torque of the bar for the models with γ = 0 and 0.5. On the other hand, the symmetric two-armed nuclear spirals in the models with γ = 1 and 1.5 are explained by gas density waves. Thus, we conclude that the mechanism responsible for the formation of symmetric two-armed nuclear spirals in barred galaxies changes from hydrodynamic shocks to gas density waves as the central mass concentration increases from γ = 0 to 1.5.
International Nuclear Information System (INIS)
Nath, N.M.; Mukharjee, A.; Das, M.K.; Sarma, J.K.
2016-01-01
We present an analysis of the xF 3 (x,Q 2 ) structure function and Gross-Llewellyn Smith(GLS) sum rule taking into account the nuclear effects and higher twist correction. This analysis is based on the results presented in [N.M. Nath, et al, Indian J. Phys. 90 (2016) 117]. The corrections due to nuclear effects predicted in several earlier analysis are incorporated to our results of xF 3 (x,Q 2 ) structure function and GLS sum rule for free nucleon, corrected upto next-next-to-leading order (NNLO) perturbative order and calculate the nuclear structure function as well as sum rule for nuclei. In addition, by means of a simple model we have extracted the higher twist contributions to the non-singlet structure function xF 3 (x,Q 2 ) and GLS sum rule in NNLO perturbative orders and then incorporated them to our results. Our NNLO results along with nuclear effect and higher twist corrections are observed to be compatible with corresponding experimental data and other phenomenological analysis. (paper)
Rock mass modification around a nuclear waste repository in welded tuff
International Nuclear Information System (INIS)
Mack, M.G.; Brandshaug, T.; Brady, B.H.
1989-08-01
This report presents the results of numerical analyses to estimate the extent of rock mass modification resulting from the presence of a High Level Waste (HLW) repository. Changes in rock mass considered are stresses and joint deformations resulting from disposal room excavation and thermal efffects induced by the heat generated by nuclear waste. rock properties and site conditions are taken from the Site Characterization Plan Conceptual Design Report for the potential repository site at Yucca Mountain, Nevada. Analyses were conducted using boundary element and distinct element methods. Room-scale models and repository-scale models were investigated for up to 500 years after waste emplacement. Results of room-scale analyses based on the thermoelastic boundary element model indicate that a zone of modified rock develops around the disposal rooms for both vertical and horizontal waste emplacement. This zone is estimated to extend a distance of roughly two room diameters from the room surface. Results from the repository-scale model, which are based on the thermoelastic boundary element model and the distinct element model, indicate a zone with modified rock mass properties starting approximately 100 m above and below the repository, with a thickness of approximately 200 m above and 150 m below the repository. Slip-prone subhorizontal features are shown to have a substantial effect on rock mass response. The estimates of rock mass modification reflect uncertainties and simplifying assumptions in the models. 32 refs., 57 figs., 1 tab
International Nuclear Information System (INIS)
Sagar, Anil; Kademani, B.S.; Vijai Kumar
2007-01-01
This paper attempts to analyse quantitatively the growth and development of Mass Spectrometry research in Nuclear Science and Technology in terms of publication output as reflected in International Nuclear Information System (INIS) database (1970-2005). During 1970-2005, a total of 10913 papers were published in various domains: Chemistry, Materials and Earth Sciences (5286) (48.44%), Physical Sciences (2367) (21.69%), Engineering and Technology (1434) (13.14), Life and Environmental Sciences (1212) (11.11), other aspects of Nuclear and Non Nuclear Energy (492) (4.51%) and Isotopes, Isotope and Radiation Applications (122) (1.12%). There were only three papers published in 1970. The highest number of papers (816) were published in 2004. The average number of publications published per year was 303.13. United States topped the list with 2247 publications followed by Germany with 1333 publications, Japan with 820 publications, France with 525 publications, and India with 460 publications. Authorship and collaboration trend was towards multi-authored papers as 81.83 percent of the papers were collaborative is indicative of the multidisciplinary nature of research activity. The most prolific authors were: S.K. Aggarwal, Bhabha Atomic Research Centre, Mumbai, India with 113 publications, W. Kutschera, University of Vienna, Austria with 85 publications, and H.C. Jain, Bhabha Atomic Research Centre, Mumbai, India with 70 publications. The highly productive institutions were: Bhabha Atomic Research Centre, Mumbai (India) with 233 publications, Argonne National Laboratory (USA) with 150 publications, Oak Ridge National Laboratory (USA) with 146 publications, University of California (USA) with 118 publications, Los Alamos National Laboratory (USA) with 104 publications and Japan Atomic Energy Research Institute (Japan) with 91 publications. The journals most preferred by the scientists for publication of papers were: Nuclear Instruments and Methods in Physics Research
Cho, Yunju; Qi, Yulin; O'Connor, Peter B; Barrow, Mark P; Kim, Sunghwan
2014-01-01
In this study, a phase-correction technique was applied to the study of crude oil spectra obtained using a 7 T Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). 7 T FT-ICR MS had not been widely used for oil analysis due to the lower resolving power compared with high field FT-ICR MS. For low field instruments, usage of data that has not been phase-corrected results in an inability to resolve critical mass splits of C3 and SH4 (3.4 mDa), and (13)C and CH (4.5 mDa). This results in incorrect assignments of molecular formulae, and discontinuous double bond equivalents (DBE) and carbon number distributions of S1, S2, and hydrocarbon classes are obtained. Application of phase correction to the same data, however, improves the reliability of assignments and produces continuous DBE and carbon number distributions. Therefore, this study clearly demonstrates that phase correction improves data analysis and the reliability of assignments of molecular formulae in crude oil anlayses.
Prockop, Leon D
2006-11-01
The events of September 11, 2001, made citizens of the world acutely aware of disasters consequent to present-day terrorism. This is a war being waged for reasons obscure to many of its potential victims. The term "NBCs" was coined in reference to terrorist weapons of mass destruction, i.e., nuclear, biological and chemical. The currently accepted acronym is "CBRNE" which includes Chemical, Biological, Radiological, Nuclear, and Explosive weapons. Non-nuclear explosives are the most common terrorist weapon now in use. Nuclear and radiological weapons are beyond the scope of this publication, which focuses on the "CBEs", i.e. chemical, biological and explosive weapons. Although neurologists will not be the first responders to CBEs, they must know about the neurological effects in order to provide diagnosis and treatment to survivors. Neurological complications of chemical, biological and explosive weapons which have or may be used by terrorists are reviewed by international experts in this publication. Management and treatment profiles are outlined.
International Nuclear Information System (INIS)
Hajek, B.K.; Stasenko, J.E.; Hashemi, S.; Bhatnagar, R.; Punch, W.F. III; Yamada, N.
1987-01-01
During the past two years, two prototype knowledge based systems have been developed at the Ohio State University. These systems were the result of collaboration between the Nuclear Engineering Program and the Laboratory for Artificial Intelligence Research (LAIR). The first system uses hierarchical classification to diagnose malfunctions of the coolant system in a General Electric Boiling Water Reactor (BWR). The second system provides a plan of action, through a process of dynamic procedure management, to stabilize the plant once an abnormal transient has occurred. The objective of this paper is to discuss the structure that has been designed to integrate the two systems. The combined system will be capable of informing plant personnel about the nature of malfunctions, and of supplying to the operator the most direct corrective procedure available. Two important features of the integrated system are faulty sensor detection, based on malfunction context and unlike sensor data, and procedure management based on the initial state of the plant. Since the two knowledge based systems were developed separately, the integration has required a separate component currently under development, the Plant Status Monitoring System (PSMS). The task of PSMS is to monitor plant parameters in order to detect an abnormal condition developing within the plant. Based on the nature of the event, PSMS is capable of directing control to either the procedure management or diagnosis component. The integrated system plays only an advisory role, and any suggested action would be executed by the plant personnel
International Nuclear Information System (INIS)
Ross, G.G.
1994-01-01
Only two techniques are really appropriate for the depth profiling of hydrogen isotopes: nuclear microanalysis (NMA) and secondary ion mass spectrometry (SIMS). The intent of this paper is to give an up to date review of both techniques and to show how they can be used in conjunction. Both techniques (SIMS and NMA) will be described briefly. NMA will divided into two different categories: nuclear reaction analysis (NRA) and elastic recoil detection (ERD). Both techniques (SIMS and NMA) will be discussed in terms of sensitivity, resolution, probing depth, quantitative measurement, generality and selectivity, beam induced effects and surface roughness effects. The principal advantages and disadvantages of each of these techniques will be specified, supporting the contention that SIMS and NMA are complementary and should be used in conjunction. Finally, some examples of, and perspectives for, the complementary use of both techniques will be presented. (Author)
International Nuclear Information System (INIS)
Blix, H.; Journe, V.
2010-01-01
This book approaches in 8 chapters the ambitious challenge of ridding the world of all mass destruction weapons: 1 - re-launching disarmament; 2 - terror weapons: nature of threats and answers (weakness of traditional answers, counter-proliferation); 3 - nuclear weapons: preventing proliferation and terrorism, reducing threat and nuclear weapons number, from regulation to banning); 4 - biological or toxin weapons; 5 - chemical weapons; 6 - vectors, anti-missile defenses and space weapons; 7 - exports control, international assistance and non-governmental actors; 8 - respect, verification, enforcement and role of the United Nations. The recommendations and works of the Commission are presented in appendix together with the declaration adopted on April 30, 2009. (J.S.)
Simple, empirical approach to predict neutron capture cross sections from nuclear masses
Couture, A.; Casten, R. F.; Cakirli, R. B.
2017-12-01
Background: Neutron capture cross sections are essential to understanding the astrophysical s and r processes, the modeling of nuclear reactor design and performance, and for a wide variety of nuclear forensics applications. Often, cross sections are needed for nuclei where experimental measurements are difficult. Enormous effort, over many decades, has gone into attempting to develop sophisticated statistical reaction models to predict these cross sections. Such work has met with some success but is often unable to reproduce measured cross sections to better than 40 % , and has limited predictive power, with predictions from different models rapidly differing by an order of magnitude a few nucleons from the last measurement. Purpose: To develop a new approach to predicting neutron capture cross sections over broad ranges of nuclei that accounts for their values where known and which has reliable predictive power with small uncertainties for many nuclei where they are unknown. Methods: Experimental neutron capture cross sections were compared to empirical mass observables in regions of similar structure. Results: We present an extremely simple method, based solely on empirical mass observables, that correlates neutron capture cross sections in the critical energy range from a few keV to a couple hundred keV. We show that regional cross sections are compactly correlated in medium and heavy mass nuclei with the two-neutron separation energy. These correlations are easily amenable to predict unknown cross sections, often converting the usual extrapolations to more reliable interpolations. It almost always reproduces existing data to within 25 % and estimated uncertainties are below about 40 % up to 10 nucleons beyond known data. Conclusions: Neutron capture cross sections display a surprisingly strong connection to the two-neutron separation energy, a nuclear structure property. The simple, empirical correlations uncovered provide model-independent predictions of
International Nuclear Information System (INIS)
Helberg, P.M.L.; Wallenius, M.; Vincent, C.; Albert, N.; Peres, P.; Truyens, J.
2013-01-01
A new LG-SIMS (Large Geometry Secondary Ion Mass Spectrometry) laboratory is currently being established at the Joint Research Centre, the Institute of Transuranium Elements for the purpose of improving the analytical capabilities within the European Commission. The laboratory will mainly be used for analysing uranium bearing aerosol particles collected on cotton swipes from nuclear Safeguards inspections but it will also be used for Nuclear Forensics and other Safeguards related applications. Until recently, this type of analysis has predominantly been performed using the small geometry CAMECA IMS 3F-7F instrument series. These instruments provide both particle screening and isotope ratio capabilities. The performance of these instruments was however limited by the occurrence of isobaric interferences, in particular for the minor isotopes ( 234 U, 236 U), that could not be resolved without compromising the transmission of the instrument. A recent breakthrough to solve this problem has been the implementation of Large Geometry SIMS, the CAMECA 1270 / 1280 / 1280-HR models, for this type of analysis. This instrument has originally been developed for geosciences applications requiring both high transmission and high mass resolution capabilities. This came out to be a key instrumental advantage also for uranium particle analyses, as it allows efficient removal of common molecular interferences with minimum loss in transmission. Furthermore an electrostatic ion optical device has been added for increasing the mass dispersion which allows the simultaneous detection of all uranium isotopes. The Automated Particle Measurement (APM) software has been developed to perform screening measurement in an automated mode. Combined with the APM screening software, LG-SIMS instruments greatly improve the overall performance and throughput of isotopic analyses of U particles for nuclear Safeguards purposes. The paper is followed by the slides of the presentation. (A.C.)
International Nuclear Information System (INIS)
Stan-Sion, C.; Catana, D.; Plostinaru, D.; Radulescu, M.; Enachescu, M.; Ivascu, M.; Marinescu, L.; Dima, R.
2000-01-01
The Accelerator Mass Spectrometry (AMS) is today the experimental physical method capable to measure the lowest concentration of a particular nuclide in a sample material. Ratios of radionuclides in the range 10 -13 - 10 -15 are normally measured with this technique, corresponding to a sensitivity which makes possible the detection of only 1 Atom in a surrounding material of about 1 Million of Billions of other Atoms. Thus, the AMS has advanced the art of Classical Mass Spectrometry (sensitivity 10 -11 ) to a sensitivity which allows for the first time the performance of special applications in environmental physics, medicine, pharmacology, geology, archaeology, measurements of radio nuclides in the Earth's atmosphere produced by cosmic-rays or by nuclear power plants, applications in astrophysics and in nuclear physics.An Accelerator Mass Spectrometry facility was constructed at the FN - 8 MV tandem accelerator of the National Institute of Physics and Nuclear Engineering . The construction was possible in the frame of a co-operation with the Technical University Munich and with financial support from IAEA-Vienna. It represents the first experimental set-up of this type in the large geographical area of Eastern Europe. The main components of the facility are: the ion injector deck, the AMS beam line and the detector systems. The injector deck is polarized at 50 kV and contains the high current sputtering ion source (spherical ionizer) followed, for beam transport, by electrostatic devices (single lenses, steerers, quadrupole lenses) a double focussing, 90 angle analyzing magnet (Danfysik), a pre-acceleration tube (NEC) and several diagnose and defining elements. The AMS samples are placed in an eight-stack magazine attached to the ion source. On the exit side of the tandem accelerator tank, a velocity filter and the particle detection system are mounted. The beam line, on the high-energy side, is optically achromatic and contains two 90 angle analyzing magnets of
Nuclear-moment studies in the odd-mass In isotopes up to N=82 using the Tilted Foils technique
We propose to study the magnetic moments of the neutron-rich odd-even In isotopes up to N=82 using the Tilted Foils technique and the recently installed $\\beta$-NMR setup at REX -ISOLDE. With only one proton hole in Z=50 and a neutron number approaching N=82, the indium isotopes should be a very good test ground for the extreme single-particle approximation and could provide essential data for tuning the nuclear interaction in the vicinity of the doubly-magic $^{132}$ Sn. Moments of single-particle states adjacent to closed shells are also crucial to determine the corrections to the M1 operator from core polarization and meson exchange effects. In addition to the 9/2$^{+}$, presumed to be of pure single proton hole configuration, the ½$^{-}$ isomeric states should shed light on a recent hypothesis of low-energy vibration/collectivity in the region. The detailed study of the Tilted Foils technique at higher masses is of crucial importance for its application for further g-factor studies and for the production...
Ftreign system studieo of hydrodynamics and heat-mass transfer at nuclear power plants
International Nuclear Information System (INIS)
Saltanov, G.A.
1981-01-01
Status and the main problems of system studies on hydrodynamics and heat-and-mass transfer at nuclear power plant transients and accidents are considered. Experimental benchmarks used for studying the loss of coolant accidents are described. The conclusion is made that contemporary level of measuring apparatus development and a large number of fast-response monitors of temperature, pressure and coolant level at most of described benchmarks permit to obtain sufficiently complete information of the behaviour of most important parts of a reactor unit during transients and accidents of different type [ru
Precision Mass Measurements of Cr-6358 : Nuclear Collectivity Towards the N =40 Island of Inversion
Mougeot, M.; Atanasov, D.; Blaum, K.; Chrysalidis, K.; Goodacre, T. Day; Fedorov, D.; Fedosseev, V.; George, S.; Herfurth, F.; Holt, J. D.; Lunney, D.; Manea, V.; Marsh, B.; Neidherr, D.; Rosenbusch, M.; Rothe, S.; Schweikhard, L.; Schwenk, A.; Seiffert, C.; Simonis, J.; Stroberg, S. R.; Welker, A.; Wienholtz, F.; Wolf, R. N.; Zuber, K.
2018-06-01
The neutron-rich isotopes Cr 58 - 63 were produced for the first time at the ISOLDE facility and their masses were measured with the ISOLTRAP spectrometer. The new values are up to 300 times more precise than those in the literature and indicate significantly different nuclear structure from the new mass-surface trend. A gradual onset of deformation is found in this proton and neutron midshell region, which is a gateway to the second island of inversion around N =40 . In addition to comparisons with density-functional theory and large-scale shell-model calculations, we present predictions from the valence-space formulation of the ab initio in-medium similarity renormalization group, the first such results for open-shell chromium isotopes.
American Society for Testing and Materials. Philadelphia
2011-01-01
1.1 These test methods cover procedures for subsampling and for chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of uranium hexafluoride UF6. Most of these test methods are in routine use to determine conformance to UF6 specifications in the Enrichment and Conversion Facilities. 1.2 The analytical procedures in this document appear in the following order: Note 1—Subcommittee C26.05 will confer with C26.02 concerning the renumbered section in Test Methods C761 to determine how concerns with renumbering these sections, as analytical methods are replaced with stand-alone analytical methods, are best addressed in subsequent publications. Sections Subsampling of Uranium Hexafluoride 7 - 10 Gravimetric Determination of Uranium 11 - 19 Titrimetric Determination of Uranium 20 Preparation of High-Purity U3O 8 21 Isotopic Analysis 22 Isotopic Analysis by Double-Standard Mass-Spectrometer Method 23 - 29 Determination of Hydrocarbons, Chlorocarbons, and Partially Substitut...
Measurement of particle size distribution and mass concentration of nuclear fuel aerosols
International Nuclear Information System (INIS)
Pickering, S.
1982-01-01
The particle size distribution and particle mass concentration of a nuclear fuel aerosol is measured by admitting the aerosol into a vertically-extending container, positioning an alpha particle detector within the container so that its window is horizontal and directed vertically, stopping the admission of aerosol into the container, detecting the alpha-activity of the particles of the aerosol sedimenting onto the detector window (for example in a series of equal time intervals until a constant level is reached), and converting the alpha-activity measurements into particle size distribution and/or particle mass concentration measurements. The detector is attached to a pivotted arm and by raising a counterweight can be lowered from the container for cleaning. (author)
American Society for Testing and Materials. Philadelphia
2004-01-01
1.1 These test methods cover procedures for the chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade boron carbide powder and pellets to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Total Carbon by Combustion and Gravimetry 7-17 Total Boron by Titrimetry 18-28 Isotopic Composition by Mass Spectrometry 29-38 Chloride and Fluoride Separation by Pyrohydrolysis 39-45 Chloride by Constant-Current Coulometry 46-54 Fluoride by Ion-Selective Electrode 55-63 Water by Constant-Voltage Coulometry 64-72 Impurities by Spectrochemical Analysis 73-81 Soluble Boron by Titrimetry 82-95 Soluble Carbon by a Manometric Measurement 96-105 Metallic Impurities by a Direct Reader Spectrometric Method 106-114
Nuclear quantum shape-phase transitions in odd-mass systems
Quan, S.; Li, Z. P.; Vretenar, D.; Meng, J.
2018-03-01
Microscopic signatures of nuclear ground-state shape-phase transitions in odd-mass Eu isotopes are explored starting from excitation spectra and collective wave functions obtained by diagonalization of a core-quasiparticle coupling Hamiltonian based on energy density functionals. As functions of the physical control parameter—the number of nucleons—theoretical low-energy spectra, two-neutron separation energies, charge isotope shifts, spectroscopic quadrupole moments, and E 2 reduced transition matrix elements accurately reproduce available data and exhibit more-pronounced discontinuities at neutron number N =90 compared with the adjacent even-even Sm and Gd isotopes. The enhancement of the first-order quantum phase transition in odd-mass systems can be attributed to a shape polarization effect of the unpaired proton which, at the critical neutron number, starts predominantly coupling to Gd core nuclei that are characterized by larger quadrupole deformation and weaker proton pairing correlations compared with the corresponding Sm isotopes.
International Nuclear Information System (INIS)
Quigg, Chris
2007-01-01
In the classical physics we inherited from Isaac Newton, mass does not arise, it simply is. The mass of a classical object is the sum of the masses of its parts. Albert Einstein showed that the mass of a body is a measure of its energy content, inviting us to consider the origins of mass. The protons we accelerate at Fermilab are prime examples of Einsteinian matter: nearly all of their mass arises from stored energy. Missing mass led to the discovery of the noble gases, and a new form of missing mass leads us to the notion of dark matter. Starting with a brief guided tour of the meanings of mass, the colloquium will explore the multiple origins of mass. We will see how far we have come toward understanding mass, and survey the issues that guide our research today.
International Nuclear Information System (INIS)
Moeller, P.; Myers, W.D.
1984-01-01
The possibility of extending the model used by Moeller and Nix in 1980 to calculate nuclear masses and fission barriers for nuclei throughout the periodic system to include provision for the existence of a neutron skin is studied. The model gives excellent fit to masses and fission barriers and improves predictions of isotopic trends in charge radii
Secondary-ion mass spectrometry: some applications in the analysis of nuclear material
International Nuclear Information System (INIS)
Christie, W.H.; Eby, R.E.; Warmack, R.J.; Landau, L.
1981-01-01
Secondary ion mass spectrometry (SIMS) has been shown to offer some significant advantages over conventional mass spectrometry for the analysis of radioactive samples. We have used SIMS for the rapid, accurate analysis of B, Li, Cs, U and Pu in various nuclear materials. In many instances, SIMS allows one to perform mass and isotopic analysis on samples that are not amenable to other mass spectrometric techniques (e.g., surface ionization, electron impact, etc.). The significant advantage that accrues from the use of SIMS for isotopic analysis of these materials is the cmplete elimination of any chemical sample preparation steps, and only sample dissolution is necessary for the application of isotope dilution methods for quantitative analysis. The high sensitivity of SIMS for B, Li, U and Pu makes it possible to analyze sufficiently small radioactive samples so that radiation is reduced to acceptable levels for safe handling. The precision of SIMS isotopic analysis for natural B samples is about 0.5% and is about 1% for natural Li samples
Isospin splitting of nucleon effective mass and symmetry energy in isotopic nuclear reactions
Guo, Ya-Fei; Chen, Peng-Hui; Niu, Fei; Zhang, Hong-Fei; Jin, Gen-Ming; Feng, Zhao-Qing
2017-10-01
Within an isospin and momentum dependent transport model, the dynamics of isospin particles (nucleons and light clusters) in Fermi-energy heavy-ion collisions are investigated for constraining the isospin splitting of nucleon effective mass and the symmetry energy at subsaturation densities. The impacts of the isoscalar and isovector parts of the momentum dependent interaction on the emissions of isospin particles are explored, i.e., the mass splittings of and (). The single and double neutron to proton ratios of free nucleons and light particles are thoroughly investigated in the isotopic nuclear reactions of 112Sn+112Sn and 124Sn+124Sn at incident energies of 50 and 120 MeV/nucleon, respectively. It is found that both the effective mass splitting and symmetry energy impact the kinetic energy spectra of the single ratios, in particular at the high energy tail (larger than 20 MeV). The isospin splitting of nucleon effective mass slightly impacts the double ratio spectra at the energy of 50 MeV/nucleon. A soft symmetry energy with stiffness coefficient of γ s=0.5 is constrained from the experimental data with the Fermi-energy heavy-ion collisions. Supported by Major State Basic Research Development Program in China (2014CB845405, 2015CB856903), National Natural Science Foundation of China (11722546, 11675226, 11675066, U1332207) and Youth Innovation Promotion Association of Chinese Academy of Sciences
Chatterjee, D.; Gulminelli, F.; Raduta, Ad. R.; Margueron, J.
2017-12-01
The question of correlations among empirical equation of state (EoS) parameters constrained by nuclear observables is addressed in a Thomas-Fermi meta-modeling approach. A recently proposed meta-modeling for the nuclear EoS in nuclear matter is augmented with a single finite size term to produce a minimal unified EoS functional able to describe the smooth part of the nuclear ground state properties. This meta-model can reproduce the predictions of a large variety of models, and interpolate continuously between them. An analytical approximation to the full Thomas-Fermi integrals is further proposed giving a fully analytical meta-model for nuclear masses. The parameter space is sampled and filtered through the constraint of nuclear mass reproduction with Bayesian statistical tools. We show that this simple analytical meta-modeling has a predictive power on masses, radii, and skins comparable to full Hartree-Fock or extended Thomas-Fermi calculations with realistic energy functionals. The covariance analysis on the posterior distribution shows that no physical correlation is present between the different EoS parameters. Concerning nuclear observables, a strong correlation between the slope of the symmetry energy and the neutron skin is observed, in agreement with previous studies.
Jankowska, Marzena; Kupka, Teobald; Stobiński, Leszek; Faber, Rasmus; Lacerda, Evanildo G; Sauer, Stephan P A
2016-02-05
Hartree-Fock and density functional theory with the hybrid B3LYP and general gradient KT2 exchange-correlation functionals were used for nonrelativistic and relativistic nuclear magnetic shielding calculations of helium, neon, argon, krypton, and xenon dimers and free atoms. Relativistic corrections were calculated with the scalar and spin-orbit zeroth-order regular approximation Hamiltonian in combination with the large Slater-type basis set QZ4P as well as with the four-component Dirac-Coulomb Hamiltonian using Dyall's acv4z basis sets. The relativistic corrections to the nuclear magnetic shieldings and chemical shifts are combined with nonrelativistic coupled cluster singles and doubles with noniterative triple excitations [CCSD(T)] calculations using the very large polarization-consistent basis sets aug-pcSseg-4 for He, Ne and Ar, aug-pcSseg-3 for Kr, and the AQZP basis set for Xe. For the dimers also, zero-point vibrational (ZPV) corrections are obtained at the CCSD(T) level with the same basis sets were added. Best estimates of the dimer chemical shifts are generated from these nuclear magnetic shieldings and the relative importance of electron correlation, ZPV, and relativistic corrections for the shieldings and chemical shifts is analyzed. © 2015 Wiley Periodicals, Inc.
International Nuclear Information System (INIS)
Warters, R.L.; Brizgys, L.M.; Lyons, B.W.
1987-01-01
The total protein mass co-isolating with the nuclear matrix or nucleoid from Chinese hamster ovary (CHO) cells was observed to increase in heated cells as a function of increasing exposure temperature between 43 0 C and 45 0 C or of exposure time at any temperature. The sedimentation distance of the CHO cell nucleoid in sucrose gradients increased with increasing exposure time at 45 0 C. Both these nuclear alterations correlated in a log-linear manner with heat-induced inhibition of DNA strand break repair. A two-fold threshold increase in nuclear matrix protein mass preceded any substantial inhibition of repair of DNA single-strand breaks. When preheated cells were incubated at 37 0 C the nuclear matrix protein mass and nucleoid sedimentation recovered with a half-time of about 5 h, while DNA single-strand-break repair recovered with a half-time of about 2 h. When preheated cells were placed at 41 0 C a further increase was observed in the nuclear matrix protein mass and the half-time of DNA strand break repair, while nucleoid sedimentation recovered toward control values. These results implicate alterations in the protein mass of the nuclear matrix in heat-induced inhibition of repair of DNA single-strand breaks. (author)
International Nuclear Information System (INIS)
Guenther-Leopold, Ines; Wernli, Beat; Kopajtic, Zlatko
2003-01-01
The determination of the burn-up is one of the essential parts in post-irradiation examinations on nuclear fuel samples. In the frame of national and international research programs the analysis of the isotopic vectors of uranium, plutonium, neodymium and some other fission products and actinides was carried out in the Hot lab of the Paul Scherrer Institute in the last years by using high-performance liquid chromatography coupled online with an inductively coupled plasma quadrupole mass spectrometer. In the meantime a multicollector ICP-MS, suitable for high precision isotope ratio measurements, was installed within the Hot lab and has been used now in combination with a chromatographic separation system for the first time for burn-up determinations of nuclear fuel samples. The results of these investigations, a comparison of both methods with the classical technique for burn-up analyses (thermal ionization mass spectrometry), the advantages and limitations of the methods and the accuracy and precision of this type of analyses are presented in the paper. (author)
Double Beta Decay and Neutrino Masses Accuracy of the Nuclear Matrix Elements
International Nuclear Information System (INIS)
Faessler, Amand
2005-01-01
The neutrinoless double beta decay is forbidden in the standard model of the electroweak and strong interaction but allowed in most Grand Unified Theories (GUT's). Only if the neutrino is a Majorana particle (identical with its antiparticle) and if it has a mass, the neutrinoless double beta decay is allowed. Apart of one claim that the neutrinoless double beta decay in 76 Ge is measured, one has only upper limits for this transition probability. But even the upper limits allow to give upper limits for the electron Majorana neutrino mass and upper limits for parameters of GUT's and the minimal R-parity violating supersymmetric model. One further can give lower limits for the vector boson mediating mainly the right-handed weak interaction and the heavy mainly right-handed Majorana neutrino in left-right symmetric GUT's. For that one has to assume that the specific mechanism is the leading one for the neutrinoless double beta decay and one has to be able to calculate reliably the corresponding nuclear matrix elements. In the present contribution, one discusses the accuracy of the present status of calculating the nuclear matrix elements and the corresponding limits of GUT's and supersymmetric parameters
International Nuclear Information System (INIS)
Bulyha, S.; Cunningham, A.; Koepf, A.; Macsik, Z.; Poths, J.
2015-01-01
In the frame of the ECAS project (Enhancing Capabilities of Safeguards Analytical Services) the IAEA Office of Safeguards Analytical Services has implemented the latest-generation inductively coupled plasma mass spectrometers, or ICP-MS, for (i) bulk analysis of uranium and plutonium isotopes in environmental inspection samples and (ii) impurity analyzes in uranium samples. The measurement accuracy for n(U-235)/ n(U-238) ratios has been improved by approximately five times with the new multi-collector ICP-MS equipment. Use of modern ICP-MS enabled also an improvement of instrumental detection limits for U-233 and U-236 and Pu isotopes by at least one order of magnitude in comparison to the values, which had been achieved with the previously used methods. The improved accuracy and precision for isotope ratio measurements is mainly due to the higher sensitivity and the possibility to simultaneously detect several U isotopes with a multi-collector detector block. Implementation of the ICP-MS has also demonstrated a possibility for an increased sample throughput. In parallel to the implementation of the ICP-MS, a new version of the ''modified total evaporation'' (MTE) method has been developed for isotopic analysis of uranium samples by multi-collector thermal ionization mass spectrometry (TIMS). The MTE method provides a measurement performance which is, in particular for minor uranium isotopes, by several orders of magnitude superior compared to the commonly used ''total evaporation'' method. The new mass spectrometric techniques significantly improve the capability of the IAEA safeguards laboratories to detect the presence of non-natural uranium and plutonium isotopes in environmental swipe samples and to identify previously imperceptible differences in nuclear ''signatures''. Thus, they enhance the IAEA's ability to obtain independent, timely and quality-assured safeguards-relevant data and ensure
International Nuclear Information System (INIS)
2010-01-01
The Centre for nuclear and mass spectroscopy (CSNSM) is a CNRS (National Centre for Scientific Research) laboratory affiliated with Paris-Sud University. The CSNSM is involved in pluri-disciplinary activities covering various scientific domains: Nuclear Structure (SNO), Nuclear Astrophysics (AN), Solid State Astrophysics (AS), Solid State Physics (PS) and Chemical Physics of Irradiation. This document presents the activity of the Centre during the 2007-2009 years: Nuclear Astrophysics; Solid State Astrophysics; Physics and Chemistry of Irradiation; Solid State Physics and cryogenic detectors; Solid State Physics, Condensed Matter and Irradiation; Structure of the Atomic Nucleus; Teaching and training activities; Spreading scientific culture; Administrative services; Electronics Group; Computer Department; Mechanics Department; RESET Service (Radiation-Environment-Safety- Maintenance-Work); SEMIRAMIS (ion source and ion beam handling)
International Nuclear Information System (INIS)
2013-07-01
The Centre for nuclear and mass spectroscopy (CSNSM) is a CNRS (National Centre for Scientific Research) laboratory affiliated with Paris-Sud University. The CSNSM is involved in pluri-disciplinary activities covering various scientific domains: Nuclear Structure (SNO), Nuclear Astrophysics (AN), Solid State Astrophysics (AS), Solid State Physics (PS) and Chemical Physics of Irradiation. This document presents the activity of the Centre during the 2010-2012 years: Nuclear Astrophysics; Solid State Astrophysics; Physics and Chemistry of Irradiation; Solid State Physics Group; Condensed Matter and Irradiation: from fundamental to functional; Structure of the Atomic Nucleus; Teaching activities; Spreading scientific culture; Administrative services; Electronics Group; Computer Department; Mechanics Department; RESET Service (Radiation-Environment-Safety- Maintenance-Work); SEMIRAMIS (ion source and ion beam handling)
Conti, C. C.; Anjos, M. J.; Salgado, C. M.
2014-09-01
X-ray fluorescence technique plays an important role in nondestructive analysis nowadays. The development of equipment, including portable ones, enables a wide assortment of possibilities for analysis of stable elements, even in trace concentrations. Nevertheless, despite of the advantages, one important drawback is radiation self-attenuation in the sample being measured, which needs to be considered in the calculation for the proper determination of elemental concentration. The mass attenuation coefficient can be determined by transmission measurement, but, in this case, the sample must be in slab shape geometry and demands two different setups and measurements. The Rayleigh to Compton scattering ratio, determined from the X-ray fluorescence spectrum, provides a link to the mass attenuation coefficient by means of a polynomial type equation. This work presents a way to construct a Rayleigh to Compton scattering ratio versus mass attenuation coefficient curve by using the MCNP5 Monte Carlo computer code. The comparison between the calculated and literature values of the mass attenuation coefficient for some known samples showed to be within 15%. This calculation procedure is available on-line at www.macx.net.br.
Faustov, R. N.; Martynenko, A. P.; Martynenko, F. A.; Sorokin, V. V.
2017-01-01
On the basis of quasipotential method in quantum electrodynamics we calculate nuclear finite size radiative corrections of order Î±(ZÎ±)5 to the Lamb shift in muonic hydrogen and helium. To construct the interaction potential of particles, which gives the necessary contributions to the energy spectrum, we use the method of projection operators to states with a definite spin. Separate analytic expressions for the contributions of the muon self-energy, the muon vertex operator and the amplitude...
Mariappan, S V Santhana; Cheng, Xun; van Breemen, Richard B; Silks, Louis A; Gupta, Goutam
2004-11-15
The formation of a GAA/TTC DNA triplex has been implicated in Friedreich's ataxia. The destabilization of GAA/TTC DNA triplexes either by pH or by binding to appropriate ligands was analyzed by nuclear magnetic resonance (NMR) and positive-ion electrospray mass spectrometry. The triplexes and duplexes were identified by changes in the NMR chemical shifts of H8, H1, H4, 15N7, and 15N4. The lowest pH at which the duplex is detectable depends upon the overall stability and the relative number of Hoogsteen C composite function G to T composite function A basepairs. A melting pH (pHm) of 7.6 was observed for the destabilization of the (GAA)2T4(TTC)2T4(CTT)2 triplex to the corresponding Watson-Crick duplex and the T4(CTT)2 overhang. The mass spectrometric analyses of (TTC)6.(GAA)6 composite function(TTC)6 triplex detected ions due to both triplex and single-stranded oligonucleotides under acidic conditions. The triplex ions disappeared completely at alkaline pH. Duplex and single strands were detectable only at neutral and alkaline pH values. Mass spectrometric analyses also showed that minor groove-binding ligands berenil, netropsin, and distamycin and the intercalating ligand acridine orange destabilize the (TTC)6.(GAA)6 composite function (TTC)6 triplex. These NMR and mass spectrometric methods may function as screening assays for the discovery of agents that destabilize GAA/TTC triplexes and as general methods for the characterization of structure, dynamics, and stability of DNA and DNA-ligand complexes.
International Nuclear Information System (INIS)
Xie Shengkai; Guo Dongfa; Tan Jing; Zhang Yanhui; Huang Qiuhong; Gao Aiguo
2013-01-01
It is very important for the rapid and reliable determination of 230 Th/ 232 Th in the thorium-230 dating. A method of measuring 230 Th/ 232 Th in natural samples by high resolution inductively coupled plasma mass spectrometer (HR-ICP-MS) was developed on the base of our former work. The precise and accurate of natural 230 Th in geology samples is challenging, as the peak tailing to the high intensity of neighboring peak at 232 Th and the mass discrimination of the instrument. The peak tailing of 238 U to 236 U was used to decrease the peak tailing effect of 232 Th to 230 Th. The mass discrimination factor K between ture and measured isotope ratio was calculated after measuring different 230 Th/ 232 Th ratio solutions. Lab used standard samples was digested in mixed acids of HN0 3 -HF-HCI-HCl0 4 , and separated by the Bio-rad AG 1 × 8 Cl - resin. The measurement method of blank-standard-blank-sample procession was used to determinate the 230 Th/ 232 Th. The measured result of 230 Th/ 232 Th was at (7.29 ± 0.34) × 10 -6 , which agreed with the reference value of (7.33 ± 0.17) × 10 -6 . (authors)
International Nuclear Information System (INIS)
Gorbunova, A.; Kramchaninov, A.
2015-01-01
Information and Analytical Centre for nuclear materials investigations was established in Russian Federation in the February 2 of 2009 by ROSATOM State Atomic Energy Corporation (the order #80). Its purpose is in preventing unauthorized access to nuclear materials and excluding their illicit traffic. Information and Analytical Centre includes analytical laboratory to provide composition and properties of nuclear materials of unknown origin for their identification. According to Regulation the Centre deals with: · identification of nuclear materials of unknown origin to provide information about their composition and properties; · arbitration analyzes of nuclear materials; · comprehensive research of nuclear and radioactive materials for developing techniques characterization of materials; · interlaboratory measurements; · measurements for control and accounting; · confirmatory measurements. Complex of non-destructive and mass-spectroscopy techniques was developed for the measurements. The complex consists of: · gamma-ray techniques on the base of MGAU, MGA and FRAM codes for uranium and plutonium isotopic composition; · gravimetrical technique with gamma-spectroscopy in addition for uranium content; · calorimetric technique for plutonium mass; · neutron multiplicity technique for plutonium mass; · measurement technique on the base of mass-spectroscopy for uranium isotopic composition; · measurement technique on the base of mass-spectroscopy for metallic impurities. Complex satisfies the state regulation requirements of ensuring the uniformity of measurements including the Russian Federation Federal Law on Ensuring the Uniformity of Measurements #102-FZ, Interstate Standard GOST R ISO/IEC 17025-2006, National Standards of Russian Federation GOST R 8.563-2009, GOST R 8.703-2010, Federal Regulations NRB-99/2009, OSPORB 99/2010. Created complex is provided in reference materials, equipment end certificated techniques. The complex is included in accredited
Estimation of the Waste Mass from a Pyro-Process of Spent Nuclear Fuel
Energy Technology Data Exchange (ETDEWEB)
Lee, Min Soo; Choi, Jong Won; Choi, Heui Joo (and others)
2008-04-15
Pyro-Process is now developing to retrieve reusable uranium and TRU, and to reduce the volume of high level waste from a nuclear power plant. In this situation, it is strongly required for the estimation of expected masses and their physical properties of the wastes. In this report, the amount of wastes and their physical properties are presupposed through some assumptions in regard to 10MTHM of Oxide Fuel with 4.5wt% U-235, 45,000 MWD/MTU, and 5yrs cooling. The produced wastes can be divided into three categories such as metal, CWF(Ceramic Waste Form), and VWF(Vitrified Waste Form). The 42 nuclrides in a spent nuclear fuel are distributed into the waste categories on the their physical and thermodynamic properties when they exist in metal, oxide, or chloride forms. The treated atomic groups are Uranium, TRU, Noble metal, Rare earth, Alkali metal, Halogens, and others. The mass of each waste is estimated by the distribution results. The off-gas waste is included into a CWF. The heat generations by the wastes in this Pyro-Process are calculated using a ORIGEN-ARP program. It is possible to estimate the amounts of wastes and their heat generation rates in this Pyro-Process analysis. These information are very helpful to design a waste container and its quantity also can be determined. The number of container and its heat generation rate will be key factor for the construction of interim storage facilities including a underground disposal site.
Jain, Anupriya; Kumar, Suneel
2014-10-01
We study the effect of isospin degree of freedom on nuclear stopping throughout the mass range 50 and 350 for two sets of isotopic systems with N/Z ≈ 1.5 and 1.8, as well as isobaric systems with N/Z = 1.0 and 1.4. Analysis is carried out at incident energies below, at, and above the energy of vanishing flow (EVF) using the isospin-dependent quantum molecular dynamics model. Our findings reveal that nuclear stopping does not show any particular behavior at the EVF. Moreover, system size effects dominate the isospin effects throughout the range of colliding geometry. The Coulomb effects, however, become important at peripheral geometry. The comparative study of the counterbalancing of Coulomb and mean field by removing the nucleon-nucleon collisions and symmetry potential clearly indicates the dominance of nucleon-nucleon cross-section over the Coulomb repulsions. Moreover, the theoretical results presented in this manuscript for the set of reactions can be experimentally verified.
International Nuclear Information System (INIS)
Jain, Anupriya; Kumar, Suneel
2014-01-01
We study the effect of isospin degree of freedom on nuclear stopping throughout the mass range 50 and 350 for two sets of isotopic systems with N/Z ≈ 1.5 and 1.8, as well as isobaric systems with N/Z = 1.0 and 1.4. Analysis is carried out at incident energies below, at, and above the energy of vanishing flow (EVF) using the isospin-dependent quantum molecular dynamics model. Our findings reveal that nuclear stopping does not show any particular behavior at the EVF. Moreover, system size effects dominate the isospin effects throughout the range of colliding geometry. The Coulomb effects, however, become important at peripheral geometry. The comparative study of the counterbalancing of Coulomb and mean field by removing the nucleon–nucleon collisions and symmetry potential clearly indicates the dominance of nucleon–nucleon cross-section over the Coulomb repulsions. Moreover, the theoretical results presented in this manuscript for the set of reactions can be experimentally verified. (paper)
International Nuclear Information System (INIS)
Boulyga, S.F.; Becker, J.S.
2000-01-01
As a result of the accident at the Chernobyl nuclear power plant (NPP) the environment was contaminated with spent nuclear fuel. The 236 U isotope was used in this study to monitor the spent uranium from nuclear fallout in soil samples collected in the vicinity of the Chernobyl NPP. A rapid and sensitive analytical procedure was developed for uranium isotopic ratio measurement in environmental samples based on inductively coupled plasma quadrupole mass spectrometry with a hexapole collision cell (HEX-ICP-QMS). The figures of merit of the HEX-ICP-QMS were studied with a plasma-shielded torch using different nebulizers (such as an ultrasonic nebulizer (USN) and Meinhard nebulizer) for solution introduction. A 238 U + ion intensity of up to 27000 MHz/ppm in HEX-ICP-QMS with USN was observed by introducing helium into the hexapole collision cell as the collision gas at a flow rate of 10 ml min -1 . The formation rate of uranium hydride ions UH + /U + of 2 x 10 -6 was obtained by using USN with a membrane desolvator. The limit of 236 U/ 238 U ratio determination in 10 μg 1 -1 uranium solution was 3 x 10 -7 corresponding to the detection limit for 236 U of 3 pg 1 -1 . The precision of uranium isotopic ratio measurements in 10 μg 1 -1 laboratory uranium isotopic standard solution was 0.13% ( 235 U/ 238 U) and 0.33% ( 236 U/ 238 U) using a Meinhard nebulizer and 0.45% ( 235 U/ 238 U) and 0.88% ( 236 U/ 238 U) using a USN. The isotopic composition of all investigated Chernobyl soil samples differed from those of natural uranium; i.e. in these samples the 236 U/ 238 U ratio ranged from 10 -5 to 10 -3 . (orig.)
International Nuclear Information System (INIS)
Airapetian, A.; Akopov, Z.
2009-11-01
The nuclear-mass dependence of azimuthal cross section asymmetries with respect to charge and longitudinal polarization of the lepton beam is studied for hard exclusive electroproduction of real photons. The observed beam-charge and beam-helicity asymmetries are attributed to the interference between the Bethe-Heitler and deeply virtual Compton scattering processes. For various nuclei, the asymmetries are extracted for both coherent and incoherent-enriched regions, which involve different (combinations of) generalized parton distributions. For both regions, the asymmetries are compared to those for a free proton, and no nuclear-mass dependence is found. (orig.)
American Society for Testing and Materials. Philadelphia
2006-01-01
1.1 These test methods cover procedures for the chemical and mass spectrometric analysis of nuclear-grade gadolinium oxide powders to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Carbon by Direct CombustionThermal Conductivity C1408 Test Method for Carbon (Total) in Uranium Oxide Powders and Pellets By Direct Combustion-Infrared Detection Method Total Chlorine and Fluorine by Pyrohydrolysis Ion Selective Electrode C1502 Test Method for Determination of Total Chlorine and Fluorine in Uranium Dioxide and Gadolinium Oxide Loss of Weight on Ignition 7-13 Sulfur by CombustionIodometric Titration Impurity Elements by a Spark-Source Mass Spectrographic C761 Test Methods for Chemical, Mass Spectrometric, Spectrochemical,Nuclear, and Radiochemical Analysis of Uranium Hexafluoride C1287 Test Method for Determination of Impurities In Uranium Dioxide By Inductively Coupled Plasma Mass Spectrometry Gadolinium Content in Gadolinium Oxid...
Directory of Open Access Journals (Sweden)
Fábio Lúcio Santos
2009-06-01
Full Text Available This paper deals with an analytical model of a rigid rotor supported by hydrodynamic journal bearings where the plane separation technique together with the Artificial Neural Network (ANN is used to predict the location and magnitude of the correction masses for balancing the rotor bearing system. The rotating system is modeled by applying the rigid shaft Stodola-Green model, in which the shaft gyroscopic moments and rotatory inertia are accounted for, in conjunction with the hydrodynamic cylindrical journal bearing model based on the classical Reynolds equation. A linearized perturbation procedure is employed to render the lubrication equations from the Reynolds equation, which allows predicting the eight linear force coefficients associated with the bearing direct and cross-coupled stiffness and damping coefficients. The results show that the methodology presented is efficient for balancing rotor systems. This paper gives a step further in the monitoring process, since Artificial Neural Network is normally used to predict, not to correct the mass unbalance. The procedure presented can be used in turbo machinery industry to balance rotating machinery that require continuous inspections. Some simulated results will be used in order to clarify the methodology presented.
International Nuclear Information System (INIS)
Sterbentz, J.W.
1997-03-01
Parametric burnup calculations are performed to estimate radionuclide isotopic mass and activity concentrations for four different Training, Research, and Isotope General Atomics (TRIGA) nuclear reactor fuel element types: (1) Aluminum-clad standard, (2) Stainless Steel-clad standard, (3) High-enrichment Fuel Life Improvement Program (FLIP), and (4) Low-enrichment Fuel Life Improvement Program (FLIP-LEU-1). Parametric activity data are tabulated for 145 important radionuclides that can be used to generate gamma-ray emission source terms or provide mass quantity estimates as a function of decay time. Fuel element decay heats and dose rates are also presented parametrically as a function of burnup and decay time. Dose rates are given at the fuel element midplane for contact, 3.0-feet, and 3.0-meter detector locations in air. The data herein are estimates based on specially derived Beginning-of-Life (BOL) neutron cross sections using geometrically-explicit TRIGA reactor core models. The calculated parametric data should represent good estimates relative to actual values, although no experimental data were available for direct comparison and validation. However, because the cross sections were not updated as a function of burnup, the actinide concentrations may deviate from the actual values at the higher burnups
International Nuclear Information System (INIS)
Marguet, S.D.
1993-01-01
Owing to the prevalence in France of nuclear generated electricity, the french utility, EDF focuses much research on fuel cycle strategy. In this context, analysis of scenarios combining problems related to planning and economics, but also reactor physics, necessitate a relatively thorough understanding of fuel response to irradiation. The main purpose of the fuel strategy program codes is to predict mass balance modifications with time for the main actinides involved in the cycle, including the minor actinides associated with the current back end fuel cycle key issues. Considering the large number of calculations performed by a strategy code in an iterative process covering a range of about a hundred years, it was important to develop basic computation modules for both the ''reactor'' and ''fabrication'' items. These had to be high speed routines, but on an accuracy level compatible with the strategy code efficiency. At the end of 1992, the EDF Research and Development Division (EDF/DER) developed a very simple, extremely fast method of calculating transuranian isotope masses. This approach, which resulted in the STRAPONTIN software, considerably increased the scope of the EDF/DER fuel strategy code TIRELIRE without undue impairment of machine time requirements for a scenario. (author). 2 figs., 2 tabs., 3 refs
Nuclear Gas Dynamics of NGC2110: A Black Hole Offset from the Host Galaxy Mass Center?
Mundell, C. G.; Ferruit, P.; Nagar, N.; Wilson, A. S.
2004-01-01
It has been suggested that the central regions of many galaxies are unlikely to be in a static steady state, with instabilities caused by sinking satellites, the influence of a supermassive black hole or residuals of galaxy formation, resulting in the nuclear black hole orbiting the galaxy center. The observational signature of such an orbiting black hole is an offset of the active nucleus (AGN) from the kinematic center defined by the galaxy rotation curve. This orbital motion may provide fuel for the AGN, as the hole 'grazes' on the ISM, and bent radio jets, due to the motion of their source. The early type (E/SO) Seyfert galaxy, NGC2210, with its striking twin, 'S'-shaped radio jets, is a unique and valuable test case for the offset-nucleus phenomenon since, despite its remarkably normal rotation curve, its kinematically-measured mass center is displaced both spatially (260 pc) and kinematically (170 km/s) from the active nucleus located in optical and radio studies. However, the central kinematics, where the rotation curve rises most steeply, have been inaccessible with ground-based resolutions. We present new, high resolution WFPC2 imaging and long-slit STIS spectroscopy of the central 300 pc of NGC2110. We discuss the structure and kinematics of gas moving in the galactic potential on subarcsecond scales and the reality of the offset between the black hole and the galaxy mass center.
Tian, Tze-Feng; Wang, San-Yuan; Kuo, Tien-Chueh; Tan, Cheng-En; Chen, Guan-Yuan; Kuo, Ching-Hua; Chen, Chi-Hsin Sally; Chan, Chang-Chuan; Lin, Olivia A; Tseng, Y Jane
2016-11-01
Two-dimensional gas chromatography time-of-flight mass spectrometry (GC×GC/TOF-MS) is superior for chromatographic separation and provides great sensitivity for complex biological fluid analysis in metabolomics. However, GC×GC/TOF-MS data processing is currently limited to vendor software and typically requires several preprocessing steps. In this work, we implement a web-based platform, which we call GC 2 MS, to facilitate the application of recent advances in GC×GC/TOF-MS, especially for metabolomics studies. The core processing workflow of GC 2 MS consists of blob/peak detection, baseline correction, and blob alignment. GC 2 MS treats GC×GC/TOF-MS data as pictures and clusters the pixels as blobs according to the brightness of each pixel to generate a blob table. GC 2 MS then aligns the blobs of two GC×GC/TOF-MS data sets according to their distance and similarity. The blob distance and similarity are the Euclidean distance of the first and second retention times of two blobs and the Pearson's correlation coefficient of the two mass spectra, respectively. GC 2 MS also directly corrects the raw data baseline. The analytical performance of GC 2 MS was evaluated using GC×GC/TOF-MS data sets of Angelica sinensis compounds acquired under different experimental conditions and of human plasma samples. The results show that GC 2 MS is an easy-to-use tool for detecting peaks and correcting baselines, and GC 2 MS is able to align GC×GC/TOF-MS data sets acquired under different experimental conditions. GC 2 MS is freely accessible at http://gc2ms.web.cmdm.tw .
Nuclear structure studies in A∼100 and A∼130 mass regions
International Nuclear Information System (INIS)
Sihotra, S.
2012-01-01
This paper reports the nuclear structure studies in the mass A∼ 100 and A∼130 regions. The investigations were performed in 98,99 Rh, 99 Pd, 96 Tc, 106,107 In, and 129,131 Cs nuclei near the proton (Z = 50) and neutron (N = 50, 64) shell closures with a view to understand the structural features that result from interplay between single particle and collective degrees of freedom. The nuclei in these regions are characterized by a small quadrupole deformation and soft to gamma deformation at low spins. In order to compare experimental results directly with the theoretical calculations, the experimental spins and level energies have been transformed into the rotating (intrinsic) frame of nucleus. The level schemes have been interpreted in the framework of theoretical model calculations. Configurations assigned to various bands are discussed in the framework of Principal/Tilted Axis Cranking (PAC/TAC) model and the deformed Hartree-Fock and angular momentum projection (PHF) calculations. Level energies and B(M1)/B(E2) ratios have, on the whole, been reproduced for the assigned configurations. Triaxial deformation in these mass regions has been inferred from the observed rotational-alignment frequencies, staggering behavior, M1 reduced transition probabilities and chiral-twin bands. Another important feature observed in these isotopes is the magnetic dipole bands generated through the shears mechanism. Observation of new E1 transitions linking the opposite-parity bands based on the proton/neutron h 11/2 and d 5/2 orbitals (Δl = 3, Δj = 1, Δπ = -1) in 131 Cs and 99 Pd provide fingerprints of possible octupole correlations in these mass-regions. (author)
Lunøe, Kristoffer; Martínez-Sierra, Justo Giner; Gammelgaard, Bente; Alonso, J Ignacio García
2012-03-01
The analytical methodology for the in vivo study of selenium metabolism using two enriched selenium isotopes has been modified, allowing for the internal correction of spectral interferences and mass bias both for total selenium and speciation analysis. The method is based on the combination of an already described dual-isotope procedure with a new data treatment strategy based on multiple linear regression. A metabolic enriched isotope ((77)Se) is given orally to the test subject and a second isotope ((74)Se) is employed for quantification. In our approach, all possible polyatomic interferences occurring in the measurement of the isotope composition of selenium by collision cell quadrupole ICP-MS are taken into account and their relative contribution calculated by multiple linear regression after minimisation of the residuals. As a result, all spectral interferences and mass bias are corrected internally allowing the fast and independent quantification of natural abundance selenium ((nat)Se) and enriched (77)Se. In this sense, the calculation of the tracer/tracee ratio in each sample is straightforward. The method has been applied to study the time-related tissue incorporation of (77)Se in male Wistar rats while maintaining the (nat)Se steady-state conditions. Additionally, metabolically relevant information such as selenoprotein synthesis and selenium elimination in urine could be studied using the proposed methodology. In this case, serum proteins were separated by affinity chromatography while reverse phase was employed for urine metabolites. In both cases, (74)Se was used as a post-column isotope dilution spike. The application of multiple linear regression to the whole chromatogram allowed us to calculate the contribution of bromine hydride, selenium hydride, argon polyatomics and mass bias on the observed selenium isotope patterns. By minimising the square sum of residuals for the whole chromatogram, internal correction of spectral interferences and mass
International Nuclear Information System (INIS)
1994-01-01
Approve it the amendments to the Treaty for the Proscription of the Nuclear Weapons in the Latin America (Treaty of TLATELOLCO), adopted for the General Conference of the Organism for the Proscription of the Nuclear Weapons in the Latin America and the Caribbean in their seventh extraordinary period of Sessions, in Mexico D:F., August of 1992, resolution 26 Not. 290(VII) [es
Kaiser, Jan; Röckmann, Thomas
2008-12-01
Gas isotope ratio mass spectrometers usually measure ion current ratios of molecules, not atoms. Often several isotopologues contribute to an ion current at a particular mass-to-charge ratio (m/z). Therefore, corrections have to be applied to derive the desired isotope ratios. These corrections are usually formulated in terms of isotope ratios (R), but this does not reflect the practice of measuring the ion current ratios of the sample relative to those of a reference material. Correspondingly, the relative ion current ratio differences (expressed as delta values) are first converted into isotopologue ratios, then into isotope ratios and finally back into elemental delta values. Here, we present a reformulation of this data reduction procedure entirely in terms of delta values and the 'absolute' isotope ratios of the reference material. This also shows that not the absolute isotope ratios of the reference material themselves, but only product and ratio combinations of them, are required for the data reduction. These combinations can be and, for carbon and oxygen have been, measured by conventional isotope ratio mass spectrometers. The frequently implied use of absolute isotope ratios measured by specially calibrated instruments is actually unnecessary. Following related work on CO2, we here derive data reduction equations for the species O2, CO, N2O and SO2. We also suggest experiments to measure the required absolute ratio combinations for N2O, SO2 and O2. As a prelude, we summarise historic and recent measurements of absolute isotope ratios in international isotope reference materials. Copyright 2008 John Wiley & Sons, Ltd.
Li, Xinpeng; Li, Hong; Liu, Yun; Xiong, Wei; Fang, Sheng
2018-03-05
The release rate of atmospheric radionuclide emissions is a critical factor in the emergency response to nuclear accidents. However, there are unavoidable biases in radionuclide transport models, leading to inaccurate estimates. In this study, a method that simultaneously corrects these biases and estimates the release rate is developed. Our approach provides a more complete measurement-by-measurement correction of the biases with a coefficient matrix that considers both deterministic and stochastic deviations. This matrix and the release rate are jointly solved by the alternating minimization algorithm. The proposed method is generic because it does not rely on specific features of transport models or scenarios. It is validated against wind tunnel experiments that simulate accidental releases in a heterogonous and densely built nuclear power plant site. The sensitivities to the position, number, and quality of measurements and extendibility of the method are also investigated. The results demonstrate that this method effectively corrects the model biases, and therefore outperforms Tikhonov's method in both release rate estimation and model prediction. The proposed approach is robust to uncertainties and extendible with various center estimators, thus providing a flexible framework for robust source inversion in real accidents, even if large uncertainties exist in multiple factors. Copyright © 2017 Elsevier B.V. All rights reserved.
International Nuclear Information System (INIS)
Haffner, D.R.
1976-01-01
1 - Description of problem or function: PACTOLUS is a code for computing nuclear power costs using the discounted cash flow method. The cash flows are generated from input unit costs, time schedules and burnup data. CLOTHO calculates and communicates to PACTOLUS mass flow data to match a specified load factor history. 2 - Method of solution: Plant lifetime power costs are calculated using the discounted cash flow method. 3 - Restrictions on the complexity of the problem - Maxima of: 40 annual time periods into which all costs and mass flows are accumulated, 20 isotopic mass flows charged into and discharged from the reactor model
2017-12-01
9 2. The Time -Dependent Schrödinger Equation ............................12 3. Stimulated Excitation to Bound States...response, including the time for reviewing instruction, searching existing data sources, gathering and maintaining the data needed, and completing and...SNM Special Nuclear Material TDC Time to Digital Converter Ti:Saph Titanium Sapphire TOF-MS Time -of-Flight Mass Spectrometry xvi THIS
International Nuclear Information System (INIS)
Gubler, Philipp; Ohtani, Keisuke
2015-01-01
The modification of the ϕ-meson at finite density is studied by using QCD sum rules in combination with the maximum entropy method. As a result, it is found that the mass shift of the ϕ-meson is strongly correlated to the strangeness content of the nucleon, , which governs the depletion of the strange quark condensate in nuclear matter. (author)
International Nuclear Information System (INIS)
Moeller, P.; Myers, W.D.
1984-03-01
We study the possibility of extending the model used by Moeller and Nix in 1980 to calculate nuclear masses and fission barriers for nuclei throughout the periodic system, to describe compressibility effects and the existence of a neutron skin. 9 references
Energy Technology Data Exchange (ETDEWEB)
Moeller, P.; Myers, W.D.
1984-03-01
We study the possibility of extending the model used by Moeller and Nix in 1980 to calculate nuclear masses and fission barriers for nuclei throughout the periodic system, to describe compressibility effects and the existence of a neutron skin. 9 references. (WHK)
Chaiamnuay, Sumapa; Bertoli, Ana M; Fernández, Mónica; Apte, Mandar; Vilá, Luis M; Reveille, John D; Alarcón, Graciela S
2007-06-01
The aim of this study was to examine the impact of an increased body mass index (BMI) on disease activity, damage accrual, fatigue, self-reported health-related quality of life (HRQOL), and fibromyalgia in patients with lupus using longitudinal data from LUMINA, a large multiethnic cohort. SLE patients (>/=4 ACR revised criteria), BMI was ascertained at T0 or first recorded. The average scores from all visits for disease activity (SLAM-R), self-reported HRQOL (physical and mental component summary measures of the SF-36) and fatigue (Fatigue Severity Scale), the score at last visit for damage accrual (SLICC Damage Index), and fibromyalgia (ACR criteria), if present at any visit, were examined for their association with an increased BMI by univariable and multivariable analyses. Three-hundred sixty-four patients were included; 28% were obese (BMI >/=30 kg/m). An increased BMI was associated with older age, less social support, higher degree of helplessness, depression, more abnormal illness-related behaviors, poorer self-reported HRQOL, fatigue, and fibromyalgia, but not with disease activity or damage accrual by univariable analyses. In multivariable analyses, BMI was independently associated with fibromyalgia but not with disease activity, fatigue, or self-reported HRQOL. An increased BMI is independently associated with presence of fibromyalgia but not with disease activity, damage accrual, fatigue or self-reported quality of life in patients with SLE. Optimizing weight merits investigation to see if it can significantly impact this pervasive SLE-associated manifestation.
International Nuclear Information System (INIS)
Bhatia, R.K.; Yadav, V.K.; Ravisankar, E.; Nataraju, V.; Gadkari, S.C.
2017-01-01
High precision isotope ratio analysis of materials of interest in nuclear and geological applications is carried out by thermal ionization mass spectrometry (TIMS) technique. One of the important mandates of Bhabha Atomic Research Centre (BARC) has been developing these instruments and several TIMS instruments have been developed and deployed at user sites covering a wide range material of interest relevant to various stages of the nuclear power cycle. The instrument designs for above applications are based on two geometries of magnetic sector ie., 15 cm sector radius and 30 cm sector radius with resolutions as 200 and 400 respectively. There has been a conscious effort to improve the the sensitivity and precision of these models by modifying the designs of the sub-systems. In the recent past, a new ion optical element viz., variable dispersion zoom optics (VDZO) was introduced in the collector system of the standard model with 30cm radius magnet, to increase the dispersion of the ion beams which enabled to fix the locations of the Faraday cups (upto 6 nos.) instead of the conventional movable ones. After establishing the usefulness of VDZO, an attempt is being made to design and develop a 20 cm magnet based TIMS which will have a much smaller foot print compared to the standard 30 cm model and also covers the usual range of elements (viz. Li - U). The ion optical design was optimized using computer simulations with SIMION 7.0 software and subsequently the mechanical design was carried out using Autocad computer software. Some of the details of this new design are presented in this abstract
Energy Technology Data Exchange (ETDEWEB)
Boulyga, S.F. [Forschungszentrum Juelich GmbH (Germany). Zentralabteilung fuer Chemische Analysen]|[Radiation Physics and Chemistry Problems Inst., Minsk (Belarus); Becker, J.S. [Forschungszentrum Juelich GmbH (Germany). Zentralabteilung fuer Chemische Analysen
2000-11-01
As a result of the accident at the Chernobyl nuclear power plant (NPP) the environment was contaminated with spent nuclear fuel. The {sup 236}U isotope was used in this study to monitor the spent uranium from nuclear fallout in soil samples collected in the vicinity of the Chernobyl NPP. A rapid and sensitive analytical procedure was developed for uranium isotopic ratio measurement in environmental samples based on inductively coupled plasma quadrupole mass spectrometry with a hexapole collision cell (HEX-ICP-QMS). The figures of merit of the HEX-ICP-QMS were studied with a plasma-shielded torch using different nebulizers (such as an ultrasonic nebulizer (USN) and Meinhard nebulizer) for solution introduction. A {sup 238}U{sup +} ion intensity of up to 27000 MHz/ppm in HEX-ICP-QMS with USN was observed by introducing helium into the hexapole collision cell as the collision gas at a flow rate of 10 ml min{sup -1}. The formation rate of uranium hydride ions UH{sup +}/U{sup +} of 2 x 10{sup -6} was obtained by using USN with a membrane desolvator. The limit of {sup 236}U/{sup 238}U ratio determination in 10 {mu}g 1{sup -1} uranium solution was 3 x 10{sup -7} corresponding to the detection limit for {sup 236}U of 3 pg 1{sup -1}. The precision of uranium isotopic ratio measurements in 10 {mu}g 1{sup -1} laboratory uranium isotopic standard solution was 0.13% ({sup 235}U/{sup 238}U) and 0.33% ({sup 236}U/{sup 238}U) using a Meinhard nebulizer and 0.45% ({sup 235}U/{sup 238}U) and 0.88% ({sup 236}U/{sup 238}U) using a USN. The isotopic composition of all investigated Chernobyl soil samples differed from those of natural uranium; i.e. in these samples the {sup 236}U/{sup 238}U ratio ranged from 10{sup -5} to 10{sup -3}. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Broeckman, A. [Rijksuniversiteit Utrecht (Netherlands)
1978-12-15
In thermal ionization mass spectrometry the phenomenon of mass discrimination has led to the use of a correction factor for isotope ratio-measurements. The correction factor is defined as the measured ratio divided by the true or accepted value of this ratio. In fact this factor corrects for systematic errors of the whole procedure; however mass discrimination is often associated just with the mass spectrometer.
Methodology for nuclear magnetic resonance and ion cyclotron resonance mass spectrometry
International Nuclear Information System (INIS)
Sehgal, Akansha
2014-01-01
This thesis encompasses methodological developments in both nuclear magnetic resonance and Fourier transform ion cyclotron resonance mass spectrometry. The NMR section explores the effects of scalar relaxation on a coupled nucleus to measure fast exchange rates. In order to quantify these rates accurately, a precise knowledge of the chemical shifts of the labile protons and of the scalar couplings is normally required. We applied the method to histidine where no such information was available a priori, neither about the proton chemical shifts nor about the one-bond scalar coupling constants J( 1 H 15 N), since the protons were invisible due to fast exchange. We have measured the exchange rates of the protons of the imidazole ring and of amino protons in histidine by indirect detection via 15 N. Not only the exchange rate constants, but also the elusive chemical shifts of the protons and the coupling constants could be determined. For the mass spectrometry section, the ion isolation project was initiated to study the effect of phase change of radiofrequency pulses. Excitation of ions in the ICR cell is a linear process, so that the pulse voltage required for ejecting ions must be inversely proportional to the pulse duration. A continuous sweep pulse propels the ion to a higher radius, whereas a phase reversal causes the ion to come to the centre. This represents the principle of 'notch ejection', wherein the ion for which the phase is reversed is retained in the ICR cell, while the remaining ions are ejected. The manuscript also contains a theoretical chapter, wherein the ion trajectories are plotted by solving the Lorentzian equation for the three-pulse scheme used for two-dimensional ICR. Through our simulations we mapped the ion trajectories for different pulse durations and for different phase relations. (author)
Energy Technology Data Exchange (ETDEWEB)
Faustov, R.N. [Dorodnicyn Computing Centre, Russian Academy of Science, Vavilov Str. 40, 119991 Moscow (Russian Federation); Martynenko, A.P. [Samara State University, Pavlov Str. 1, 443011 Samara (Russian Federation); Samara State Aerospace University named after S.P. Korolyov, Moskovskoye Shosse 34, 443086 Samara (Russian Federation); Martynenko, G.A.; Sorokin, V.V. [Samara State University, Pavlov Str. 1, 443011 Samara (Russian Federation)
2014-06-02
On the basis of quasipotential method in quantum electrodynamics we calculate nuclear finite size radiative corrections of order α(Zα){sup 5} to the hyperfine structure of S-wave energy levels in muonic hydrogen and muonic deuterium. For the construction of the particle interaction operator we employ the projection operators on the particle bound states with definite spins. The calculation is performed in the infrared safe Fried–Yennie gauge. Modern experimental data on the electromagnetic form factors of the proton and deuteron are used.
International Nuclear Information System (INIS)
Faustov, R.N.; Martynenko, A.P.; Martynenko, G.A.; Sorokin, V.V.
2014-01-01
On the basis of quasipotential method in quantum electrodynamics we calculate nuclear finite size radiative corrections of order α(Zα) 5 to the hyperfine structure of S-wave energy levels in muonic hydrogen and muonic deuterium. For the construction of the particle interaction operator we employ the projection operators on the particle bound states with definite spins. The calculation is performed in the infrared safe Fried–Yennie gauge. Modern experimental data on the electromagnetic form factors of the proton and deuteron are used.
Hayes, Alison J; Clarke, Philip M; Lung, Tom Wc
2011-09-25
Many studies have documented the bias in body mass index (BMI) determined from self-reported data on height and weight, but few have examined the change in bias over time. Using data from large, nationally-representative population health surveys, we examined change in bias in height and weight reporting among Australian adults between 1995 and 2008. Our study dataset included 9,635 men and women in 1995 and 9,141 in 2007-2008. We investigated the determinants of the bias and derived correction equations using 2007-2008 data, which can be applied when only self-reported anthropometric data are available. In 1995, self-reported BMI (derived from height and weight) was 1.2 units (men) and 1.4 units (women) lower than measured BMI. In 2007-2008, there was still underreporting, but the amount had declined to 0.6 units (men) and 0.7 units (women) below measured BMI. The major determinants of reporting error in 2007-2008 were age, sex, measured BMI, and education of the respondent. Correction equations for height and weight derived from 2007-2008 data and applied to self-reported data were able to adjust for the bias and were accurate across all age and sex strata. The diminishing reporting bias in BMI in Australia means that correction equations derived from 2007-2008 data may not be transferable to earlier self-reported data. Second, predictions of future overweight and obesity in Australia based on trends in self-reported information are likely to be inaccurate, as the change in reporting bias will affect the apparent increase in self-reported obesity prevalence.
Farag, Mohamed A
2014-01-01
The number of botanical dietary supplements in the market has recently increased primarily due to increased health awareness. Standardization and quality control of the constituents of these plant extracts is an important topic, particularly when such ingredients are used long term as dietary supplements, or in cases where higher doses are marketed as drugs. The development of fast, comprehensive, and effective untargeted analytical methods for plant extracts is of high interest. Nuclear magnetic resonance spectroscopy and mass spectrometry are the most informative tools, each of which enables high-throughput and global analysis of hundreds of metabolites in a single step. Although only one of the two techniques is utilized in the majority of plant metabolomics applications, there is a growing interest in combining the data from both platforms to effectively unravel the complexity of plant samples. The application of combined MS and NMR in the quality control of nutraceuticals forms the major part of this review. Finally I will look at the future developments and perspectives of these two technologies for the quality control of herbal materials.
Cleveland, M. J.; Ziemba, L. D.; Griffin, R. J.; Dibb, J. E.; Anderson, C. H.; Lefer, B.; Rappenglück, B.
2012-07-01
Particulate matter was measured during August and September of 2006 in Houston as part of the Texas Air Quality Study II Radical and Aerosol Measurement Project. Aerosol size and composition were determined using an Aerodyne quadrupole aerosol mass spectrometer. Aerosol was dominated by sulfate (4.1 ± 2.6 μg m-3) and organic material (5.5 ± 4.0 μg m-3), with contributions of organic material from both primary (˜32%) and secondary (˜68%) sources. Secondary organic aerosol appears to be formed locally. In addition, 29 aerosol filter samples were analyzed using proton nuclear magnetic resonance (1H NMR) spectroscopy to determine relative concentrations of organic functional groups. Houston aerosols are less oxidized than those observed elsewhere, with smaller relative contributions of carbon-oxygen double bonds. These particles do not fit 1H NMR source apportionment fingerprints for identification of secondary, marine, and biomass burning organic aerosol, suggesting that a new fingerprint for highly urbanized and industrially influenced locations be established.
International Nuclear Information System (INIS)
Pond, R.B.; Matos, J.E.
1996-05-01
As part of the Department of Energy's spent nuclear fuel acceptance criteria, the mass of uranium and transuranic elements in spent research reactor fuel must be specified. These data are, however, not always known or readily determined. It is the purpose of this report to provide estimates of these data for some of the more common research reactor fuel assembly types. The specific types considered here are MTR, TRIGA and DIDO fuel assemblies. The degree of physical protection given to spent fuel assemblies is largely dependent upon the photon dose rate of the spent fuel material. These data also, are not always known or readily determined. Because of a self-protecting dose rate level of radiation (dose rate greater than 100 ren-x/h at I m in air), it is important to know the dose rate of spent fuel assemblies at all time. Estimates of the photon dose rate for spent MTR, TRIGA and DIDO-type fuel assemblies are given in this report
Jallu, F.; Loche, F.
2008-08-01
Within the framework of radioactive waste control, non-destructive assay (NDA) methods may be employed. The active neutron interrogation (ANI) method is now well-known and effective in quantifying low α-activity fissile masses (mainly 235U, 239Pu, 241Pu) with low densities, i.e. less than about 0.4, in radioactive waste drums of volumes up to 200 l. The PROMpt Epithermal and THErmal interrogation Experiment (PROMETHEE [F. Jallu, A. Mariani, C. Passard, A.-C. Raoux, H. Toubon, Alpha low level waste control: improvement of the PROMETHEE 6 assay system performances. Nucl. Technol. 153 (January) (2006); C. Passard, A. Mariani, F. Jallu, J. Romeyer-Dherber, H. Recroix, M. Rodriguez, J. Loridon, C. Denis, PROMETHEE: an alpha low level waste assay system using passive and active neutron measurement methods. Nucl. Technol. 140 (December) (2002) 303-314]) based on ANI has been under development since 1996 to reach the incinerating α low level waste (LLW) criterion of about 50 Bq[α] per gram of crude waste (≈50 μg Pu) in 118 l drums on the date the drums are conditioned. Difficulties arise when dealing with matrices containing neutron energy moderators such as H and neutron absorbents such as Cl. These components may have a great influence on the fissile mass deduced from the neutron signal measured by ANI. For example, the calibration coefficient measured in a 118 l drum containing a cellulose matrix (density d = 0.144 g cm -3) may be 50 times higher than that obtained in a poly-vinyl-chloride matrix ( d = 0.253 g cm -3). Without any information on the matrix, the fissile mass is often overestimated due to safety procedures and by considering the most disadvantageous calibration coefficient corresponding to the most absorbing and moderating calibration matrix. The work discussed in this paper was performed at the CEA Nuclear Measurement Laboratory in France. It concerns the development of a matrix effect correction method, which consists in identifying and quantifying
International Nuclear Information System (INIS)
Jallu, F.; Loche, F.
2008-01-01
Within the framework of radioactive waste control, non-destructive assay (NDA) methods may be employed. The active neutron interrogation (ANI) method is now well-known and effective in quantifying low α-activity fissile masses (mainly 235 U, 239 Pu, 241 Pu) with low densities, i.e. less than about 0.4, in radioactive waste drums of volumes up to 200 l. The PROMpt Epithermal and THErmal interrogation Experiment (PROMETHEE [F. Jallu, A. Mariani, C. Passard, A.-C. Raoux, H. Toubon, Alpha low level waste control: improvement of the PROMETHEE 6 assay system performances. Nucl. Technol. 153 (January) (2006); C. Passard, A. Mariani, F. Jallu, J. Romeyer-Dherber, H. Recroix, M. Rodriguez, J. Loridon, C. Denis, PROMETHEE: an alpha low level waste assay system using passive and active neutron measurement methods. Nucl. Technol. 140 (December) (2002) 303-314]) based on ANI has been under development since 1996 to reach the incinerating α low level waste (LLW) criterion of about 50 Bq[α] per gram of crude waste (∼50 μg Pu) in 118 l drums on the date the drums are conditioned. Difficulties arise when dealing with matrices containing neutron energy moderators such as H and neutron absorbents such as Cl. These components may have a great influence on the fissile mass deduced from the neutron signal measured by ANI. For example, the calibration coefficient measured in a 118 l drum containing a cellulose matrix (density d = 0.144 g cm -3 ) may be 50 times higher than that obtained in a poly-vinyl-chloride matrix (d = 0.253 g cm -3 ). Without any information on the matrix, the fissile mass is often overestimated due to safety procedures and by considering the most disadvantageous calibration coefficient corresponding to the most absorbing and moderating calibration matrix. The work discussed in this paper was performed at the CEA Nuclear Measurement Laboratory in France. It concerns the development of a matrix effect correction method, which consists in identifying and
Energy Technology Data Exchange (ETDEWEB)
Jallu, F. [Commissariat a l' Energie Atomique, CEA, DEN, Nuclear Measurement Laboratory, Bat. 224, 13108 Saint Paul lez Durance (France)], E-mail: fanny.jallu@cea.fr; Loche, F. [Commissariat a l' Energie Atomique, CEA, DEN, Nuclear Measurement Laboratory, Bat. 224, 13108 Saint Paul lez Durance (France)
2008-08-15
Within the framework of radioactive waste control, non-destructive assay (NDA) methods may be employed. The active neutron interrogation (ANI) method is now well-known and effective in quantifying low {alpha}-activity fissile masses (mainly {sup 235}U, {sup 239}Pu, {sup 241}Pu) with low densities, i.e. less than about 0.4, in radioactive waste drums of volumes up to 200 l. The PROMpt Epithermal and THErmal interrogation Experiment (PROMETHEE [F. Jallu, A. Mariani, C. Passard, A.-C. Raoux, H. Toubon, Alpha low level waste control: improvement of the PROMETHEE 6 assay system performances. Nucl. Technol. 153 (January) (2006); C. Passard, A. Mariani, F. Jallu, J. Romeyer-Dherber, H. Recroix, M. Rodriguez, J. Loridon, C. Denis, PROMETHEE: an alpha low level waste assay system using passive and active neutron measurement methods. Nucl. Technol. 140 (December) (2002) 303-314]) based on ANI has been under development since 1996 to reach the incinerating {alpha} low level waste (LLW) criterion of about 50 Bq[{alpha}] per gram of crude waste ({approx}50 {mu}g Pu) in 118 l drums on the date the drums are conditioned. Difficulties arise when dealing with matrices containing neutron energy moderators such as H and neutron absorbents such as Cl. These components may have a great influence on the fissile mass deduced from the neutron signal measured by ANI. For example, the calibration coefficient measured in a 118 l drum containing a cellulose matrix (density d = 0.144 g cm{sup -3}) may be 50 times higher than that obtained in a poly-vinyl-chloride matrix (d = 0.253 g cm{sup -3}). Without any information on the matrix, the fissile mass is often overestimated due to safety procedures and by considering the most disadvantageous calibration coefficient corresponding to the most absorbing and moderating calibration matrix. The work discussed in this paper was performed at the CEA Nuclear Measurement Laboratory in France. It concerns the development of a matrix effect correction
International Nuclear Information System (INIS)
Tsuchida, Tatsuro; Kimura, Hiroshi
2011-01-01
The mass media has the potential to effect the utilization of nuclear power in Japan. In most cases journalists contact PR staff of the nuclear energy industry (hereinafter called 'the industry') to collect information about various events of nuclear energy. The industry is always ready to distribute related information and hold a press conference timely when necessary. In terms of the organizational structure for the PR activities each electric power company organizes the PR section in-house. The PR staff provides journalists with information on a daily basis. For the purpose of grasping the mass media's awareness, the author conducted interviews with 22 journalists who had experience in reporting news on nuclear energy subjects. The result showed that the journalists recognized the necessity of nuclear energy. The interviewees suggested that a proper press launch should be needed at just the right time especially in emergency situations and a press release should be more easily understandable. This interview showed that journalists considered the media reports as reflection of citizens' opinion. Most of the journalists realize that the influence of the media coverage should not be negligible and they acknowledge commutation between the two sides is gradually improved compared to before. (author)
International Nuclear Information System (INIS)
Anon.
1977-01-01
This guide describes the type of information needed to evaluate an application for a specific license for receipt, possession, use, and transfer of special nuclear material. It is intended for applicants requesting authorization to possess and use up to 2000 grams of plutonium, total, in the form of sealed plutonium-beryllium neutron sources, and any special nuclear material in quantities and forms not sufficient to form a critical mass. The latter quantities are considered to be 350 grams of contained uranium-235, 200 grams of uranium-233, 200 grams of plutonium (in any form other than plutonium-beryllium neutron sources) or any combination of them
Isochronicity correction in the CR storage ring
International Nuclear Information System (INIS)
Litvinov, S.; Toprek, D.; Weick, H.; Dolinskii, A.
2013-01-01
A challenge for nuclear physics is to measure masses of exotic nuclei up to the limits of nuclear existence which are characterized by low production cross-sections and short half-lives. The large acceptance Collector Ring (CR) [1] at FAIR [2] tuned in the isochronous ion-optical mode offers unique possibilities for measuring short-lived and very exotic nuclides. However, in a ring designed for maximal acceptance, many factors limit the resolution. One point is a limit in time resolution inversely proportional to the transverse emittance. But most of the time aberrations can be corrected and others become small for large number of turns. We show the relations of the time correction to the corresponding transverse focusing and that the main correction for large emittance corresponds directly to the chromaticity correction for transverse focusing of the beam. With the help of Monte-Carlo simulations for the full acceptance we demonstrate how to correct the revolution times so that in principle resolutions of Δm/m=10 −6 can be achieved. In these calculations the influence of magnet inhomogeneities and extended fringe fields are considered and a calibration scheme also for ions with different mass-to-charge ratio is presented
Energy Technology Data Exchange (ETDEWEB)
Boatto, Gianpiero [Department of Toxicological Chemistry, University of Sassari, Sassari (Italy); Culeddu, Nicola [CNR Biomolecular Chemistry Institute, Sassari (Italy); Testa, Cecilia [IZS della Sardegna, Sassari (Italy); Neri, Bruno [IZS delle Regioni Lazio e Toscana, Rome (Italy); Brambilla, Gianfranco [Istituto Superiore di Sanita, Environment Department, Toxicological Chemistry Unit, Rome (Italy)]. E-mail: g.brambi@iss.it; Barbosa, Jorge [LNIV, Lisbon (Portugal); Cruz, Clara [LNIV, Lisbon (Portugal)
2007-03-14
In animal production, it is consolidated the synthesis and the illegal use of growth promoters of new generation, able to skip routine screening and confirmatory analysis. In this work it is reported the nuclear magnetic resonance (NMR) and the mass spectrometry identification of a probable new adrenergic drug found in a feed premix. The substance was selectively purified on alpha 1 acid glycoprotein affinity columns; then its structure was first achieved by recording the {sup 13}C NMR spectrum that gave the total number of carbons of the molecule, successively sorted by DEPT experiments into quaternary, CH, CH{sub 2}, and CH{sub 3} groups. However, the complete assignments of all resonances were derived from the bi-dimensional analysis and the crucial indications from the {sup 1}H-{sup 13}C reverse experiments. Further characterisation was performed by atmospheric pressure chemical ionisation both in positive and negative ion mode, matching the molecular ion and the fragmentation pattern with those of most recently described new adrenergic agonists. After the loss of a ter-butylic group, the structure shows an internal symmetry along with the presence of Chlorine clusters. The proposed formula of the compound, the 8,8'-diamino-9,9'-dichloro-1-terbutyl-1,1',4,4-tetrahydro-5H,5'H-2,2'-bi -1-benzazepine-5,5'-dione, partially resembles that of Zilpaterol for the presence of a heterocyclic ring; Further work is in progress to characterise the structure-activity relationship.
Role of cytogenetic biodosimetry in meeting the needs of a mass casualty radiological/nuclear event
International Nuclear Information System (INIS)
Balajee, A.S.; Dainiak, N.
2016-01-01
Radiological/nuclear (R/N) terrorism constitutes a potential threat to all nations that can result in significant morbidity and mortality among hundreds of thousands individuals. In addition to the timing and severity of clinical signs and symptoms, individual radiation dose informs risk assessment and mitigation of radiation-associated injuries. The 'gold standard' for individual whole-body radiation dosimetry is the dicentric chromosome assay. The Cytogenetics Biodosimetry Laboratory at REAC/TS is a WHO Collaborating Centre and member of IAEA's RANET that employs DCA, as well as fluorescence in situ hybridization, premature chromosome condensation, and micronuclei assays to assess radiation dose. The quality of dose estimates and standard operating procedures for DCA at REAC/TS have been validated in multiple inter-comparison studies involving CBLs in Asia, Europe, North America and South America. DCA is scalable to meet the needs of a mass casualty R/N incident. The CBL at REAC/TS has made seminal contributions to augment surge capacity for DCA and develop CBLs worldwide through initiatives such as modification of 'Share Point' in 2010 to transmit images of metaphases for simultaneous telescoring; (2) development of an on-line training program for metaphase scoring; (3) proactive participation as a WCC to create ISO standards; and (4) guidance of regulatory agencies to monitor quality of results and SOPs. The precision of dose estimates by DCA can be vastly improved by using a universal calibration curve. With this view, REAC/TS has organized a collaboration with CBLs at Health Canada and Yale University to construct and validate a common calibration curve for gamma rays
International Nuclear Information System (INIS)
Persaud, K.
1965-01-01
We have carried out the synthesis of: - phenanthrene - its five monomethyl derivatives - three dimethyl derivatives - two trimethyl derivatives. We have then purified these products as well as a certain number of others obtained from various sources. We have been able to obtain in the majority of cases, a purity of 99.5 per cent or over, these figures being obtained by low voltage mass spectrometry. Finally we have recorded the infrared, ultraviolet, nuclear magnetic resonance and mass spectra of these products for which an atlas has been drawn up. (author) [fr
International Nuclear Information System (INIS)
Boudjema, Fawzi; Dombey, Norman
1989-01-01
The standard 'electroweak' picture, synthesizing electromagnetism with the weak nuclear force (via the gauge symmetry group SU(2) x U(1)) agrees so far with all experimental results. Despite these impressive successes, it is only a crude overall check of the model since only the results of first-order approximations (perturbations) have been verified
International Nuclear Information System (INIS)
Gallego, Eduardo; Cantone, Marie Claire; Oughton, Deborah H.; Tomkiv, Yevgeniya; Perko, Tanja; Prezelj, Iztok
2017-01-01
This paper presents the results of a large study of 1340 articles published by two major newspapers in six European countries (Belgium, Italy, Norway, Slovenia, Spain and Russia) in the first 2 months after the Fukushima Daiichi nuclear disaster. The focus of the analysis is on the application and overall impact of protective actions, both during the emergency phase and later, how the newspapers describe those actions, which differences were apparent between countries and what recommendations can be extracted in order to improve general communication about these issues. A clear lesson is that, even under uncertainty and recognising limitations, responsible authorities need to provide transparent, clear and understandable information to the public and the mass media right from the beginning of the early phase of any nuclear emergency. Clear, concise messages should be given. Mass media could play a key role in reassuring the public if the countermeasures are clearly explained. (authors)
2016-12-01
masses collide, they form a supercritical mass . Criticality refers to the neutron population within the system. A critical system is one that can...Spectrometry, no. 242, pp. 161–168, 2005. [9] S. Raeder, “Trace analysis of actinides in the environment by means of resonance ionization mass ...first ionization potential of actinide elements by resonance ionization mass spectrometry.” Spectrochimica Acta part B: Atomic Spectroscopy. vol. 52
Chakrabarti, Suman; Schmidt, George R.; Thio, Y. C.; Hurst, Chantelle M.
1999-01-01
A preliminary model for spacecraft propulsion performance analysis based on nuclear gain and subsystem mass-power balances are presented in viewgraph form. For very fast missions with straight-line trajectories, it has been shown that mission trip time is proportional to the cube root of alpha. Analysis of spacecraft power systems via a power balance and examination of gain vs. mass-power ratio has shown: 1) A minimum gain is needed to have enough power for thruster and driver operation; and 2) Increases in gain result in decreases in overall mass-power ratio, which in turn leads to greater achievable accelerations. However, subsystem mass-power ratios and efficiencies are crucial: less efficient values for these can partially offset the effect of nuclear gain. Therefore, it is of interest to monitor the progress of gain-limited subsystem technologies and it is also possible that power-limited systems with sufficiently low alpha may be competitive for such ambitious missions. Topics include Space flight requirements; Spacecraft energy gain; Control theory for performance; Mission assumptions; Round trips: Time and distance; Trip times; Vehicle acceleration; and Minimizing trip times.
On-line nuclear half life and spectroscopic measurements on mass-separated fission product nuclei
International Nuclear Information System (INIS)
McDonald, J.; Fogelberg, B.; Baecklin, A.
1979-01-01
A description is given of the methods and equipment employed for nuclear spectroscopy studies of short lived fission product nuclei at the OSIRIS ISOL facility in Studsvik, Sweden. Furthermore a table of new nuclear half-lives measured with this equipment is presented. (author)
International Nuclear Information System (INIS)
Beenakker, W.J.P.
1989-01-01
The prospect of high accuracy measurements investigating the weak interactions, which are expected to take place at the electron-positron storage ring LEP at CERN and the linear collider SCL at SLAC, offers the possibility to study also the weak quantum effects. In order to distinguish if the measured weak quantum effects lie within the margins set by the standard model and those bearing traces of new physics one had to go beyond the lowest order and also include electroweak radiative corrections (EWRC) in theoretical calculations. These higher-order corrections also can offer the possibility of getting information about two particles present in the Glashow-Salam-Weinberg model (GSW), but not discovered up till now, the top quark and the Higgs boson. In ch. 2 the GSW standard model of electroweak interactions is described. In ch. 3 some special techniques are described for determination of integrals which are responsible for numerical instabilities caused by large canceling terms encountered in the calculation of EWRC effects, and methods necessary to get hold of the extensive algebra typical for EWRC. In ch. 4 various aspects related to EWRC effects are discussed, in particular the dependence of the unknown model parameters which are the masses of the top quark and the Higgs boson. The processes which are discussed are production of heavy fermions from electron-positron annihilation and those of the fermionic decay of the Z gauge boson. (H.W.). 106 refs.; 30 figs.; 6 tabs.; schemes
American Society for Testing and Materials. Philadelphia
2010-01-01
1.1 These test methods cover procedures for the chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade plutonium dioxide powders and pellets to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Plutonium Sample Handling 8 to 10 Plutonium by Controlled-Potential Coulometry Plutonium by Ceric Sulfate Titration Plutonium by Amperometric Titration with Iron(II) Plutonium by Diode Array Spectrophotometry Nitrogen by Distillation Spectrophotometry Using Nessler Reagent 11 to 18 Carbon (Total) by Direct Combustion–Thermal Conductivity 19 to 30 Total Chlorine and Fluorine by Pyrohydrolysis 31 to 38 Sulfur by Distillation Spectrophotometry 39 to 47 Plutonium Isotopic Analysis by Mass Spectrometry Rare Earth Elements by Spectroscopy 48 to 55 Trace Elements by Carrier–Distillation Spectroscopy 56 to 63 Impurities by ICP-AES Impurity Elements by Spark-Source Mass Spectrography 64 to 70 Moisture by the Coulomet...
Directory of Open Access Journals (Sweden)
R.N. Faustov
2017-12-01
Full Text Available On the basis of quasipotential method in quantum electrodynamics we calculate nuclear finite size radiative corrections of order Î±(ZÎ±5 to the Lamb shift in muonic hydrogen and helium. To construct the interaction potential of particles, which gives the necessary contributions to the energy spectrum, we use the method of projection operators to states with a definite spin. Separate analytic expressions for the contributions of the muon self-energy, the muon vertex operator and the amplitude with spanning photon are obtained. We present also numerical results for these contributions using modern experimental data on the electromagnetic form factors of light nuclei. Keywords: Lamb shift, Muonic atoms, Quantum electrodynamics
Intracellular lysyl oxidase: Effect of a specific inhibitor on nuclear mass in proliferating cells
Energy Technology Data Exchange (ETDEWEB)
Saad, Fawzy A. [Laboratory for the Study of Skeletal Disorders and Rehabilitation, Department of Orthopedics, Children' s Hospital Boston, 300 Longwood Avenue EN926, Boston, MA 02115 (United States); Harvard Medical School, Boston, MA 02115 (United States); Torres, Marie [Laboratory for the Study of Skeletal Disorders and Rehabilitation, Department of Orthopedics, Children' s Hospital Boston, 300 Longwood Avenue EN926, Boston, MA 02115 (United States); Wang, Hao [Laboratory for the Study of Skeletal Disorders and Rehabilitation, Department of Orthopedics, Children' s Hospital Boston, 300 Longwood Avenue EN926, Boston, MA 02115 (United States); Harvard Medical School, Boston, MA 02115 (United States); Graham, Lila, E-mail: lilagraham@cs.com [Laboratory for the Study of Skeletal Disorders and Rehabilitation, Department of Orthopedics, Children' s Hospital Boston, 300 Longwood Avenue EN926, Boston, MA 02115 (United States); Harvard Medical School, Boston, MA 02115 (United States)
2010-06-11
LOX, the principal enzyme involved in crosslinking of collagen, was the first of several lysyl oxidase isotypes to be characterized. Its active form was believed to be exclusively extracellular. Active LOX was later reported to be present in cell nuclei; its function there is unknown. LOX expression opposes the effect of mutationally activated Ras, which is present in about 30% of human cancers. The mechanism of LOX in countering the action of Ras is also unknown. In the present work, assessment of nuclear protein for possible effects of lysyl oxidase activity led to the discovery that proliferating cells dramatically increase their nuclear protein content when exposed to BAPN ({beta}-aminopropionitrile), a highly specific lysyl oxidase inhibitor that reportedly blocks LOX inhibition of Ras-induced oocyte maturation. In three cell types (PC12 cells, A7r5 smooth muscle cells, and NIH 3T3 fibroblasts), BAPN caused a 1.8-, 1.7-, and 2.1-fold increase in total nuclear protein per cell, respectively, affecting all major components in both nuclear matrix and chromatin fractions. Since nuclear size is correlated with proliferative status, enzyme activity restricting nuclear growth may be involved in the lysyl oxidase tumor suppressive effect. Evidence is also presented for the presence of apparent lysyl oxidase isotype(s) containing a highly conserved LOX active site sequence in the nuclei of PC12 cells, which do not manufacture extracellular lysyl oxidase substrates. Results reported here support the hypothesis that nuclear lysyl oxidase regulates nuclear growth, and thereby modulates cell proliferation.
Energy Technology Data Exchange (ETDEWEB)
Giordanengo, Remi [Universites Aix-Marseille I, II et III - CNRS, UMR 6264: Laboratoire Chimie Provence, Spectrometries Appliquees a la Chimie Structurale, F-13397 Marseille (France); Viel, Stephane [Aix-Marseille Universite - CNRS, UMR 6263: Institut des Sciences Moleculaires de Marseille, Chimiometrie et Spectrometries, F-13397 Marseille (France); Hidalgo, Manuel; Allard-Breton, Beatrice [ARKEMA, Centre de Recherche Rhone Alpes, Rue Henri Moissan, F-69493 Pierre-Benite (France); Thevand, Andre [Universites Aix-Marseille I, II et III - CNRS, UMR 6264: Laboratoire Chimie Provence, Spectrometries Appliquees a la Chimie Structurale, F-13397 Marseille (France); Charles, Laurence, E-mail: laurence.charles@univ-provence.fr [Universites Aix-Marseille I, II et III - CNRS, UMR 6264: Laboratoire Chimie Provence, Spectrometries Appliquees a la Chimie Structurale, F-13397 Marseille (France)
2009-11-03
Mass spectrometry (MS) and nuclear magnetic resonance (NMR) have been combined to achieve the complete microstructural characterization of a poly(methacrylic acid)-poly(methyl methacrylate) (PMAA-PMMA) copolymer synthesized by nitroxide-mediated polymerization. Various PMAA-PMMA species could be identified which mainly differ in terms of terminaisons. {sup 1}H and {sup 13}C NMR experiments revealed the structure of the end-groups as well as the proportion of each co-monomer in the copolymers. These end-group masses were further confirmed from m/z values of doubly charged copolymer anions detected in the single stage mass spectrum. In contrast, copolymer composition derived from MS data was not consistent with NMR results, obviously due to strong mass bias well known to occur during electrospray ionization of these polymeric species. Tandem mass spectrometry could reveal the random nature of the copolymer based on typical dissociation reactions, i.e., water elimination occurred from any two contiguous MAA units while MAA-MMA pairs gave rise to the loss of a methanol molecule. Polymer backbone cleavages were also observed to occur and gave low abundance fragment ions which allowed the structure of the initiating end-group to be confirmed.
Chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade mixed oxides [(U,Pu)O2
International Nuclear Information System (INIS)
Anon.
1981-01-01
Mixed oxide, a mixture of uranium and plutonium oxides, is used as a nuclear-reactor fuel in the form of pellets. The plutonium content may be up to 10 wt %, and the diluent uranium may be of any U-235 enrichment. In order to be suitable for use as a nuclear fuel, the material must meet certain criteria for combined uranium and plutonium content, effective fissile content, and impurity content. Analytical procedures used to determine if mixed oxides comply with specifications are: uranium by controlled-potential coulometry; plutonium by controlled-potential coulometry; plutonium by amperometric titration with iron (II); nitrogen by distillation spectrophotometry using Nessler reagent; carbon (total) by direct combustion-thermal-conductivity; total chlorine and fluorine by pyrohydrolysis; sulfur by distillation-spectrophotometry; moisture by the coulometric, electrolytic moisture analyzer; isotopic composition by mass spectrometry; rare earths by copper spark spectroscopy; trace impurities by carrier distillation spectroscopy; impurities by spark-source mass spectrography; total gas in reactor-grade mixed dioxide pellets; tungsten by dithiol-spectrophotometry; rare earth elements by spectroscopy; plutonium-238 isotopic abundance by alpha spectrometry; uranium and plutonium isotopic analysis by mass spectrometry; oxygen-to-metal atom ratio by gravimetry
American Society for Testing and Materials. Philadelphia
1999-01-01
1.1 These test methods cover procedures for the chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade uranium dioxide powders and pellets to determine compliance with specifications. 1.2 This test method covers the determination of uranium and the oxygen to uranium atomic ratio in nuclear-grade uranium dioxide powder and pellets. 1.4 This test method covers the determination of chlorine and fluorine in nuclear-grade uranium dioxide. With a 1 to 10-g sample, concentrations of 5 to 200 g/g of chlorine and 1 to 200 μg/g of fluorine are determined without interference. 1.5 This test method covers the determination of moisture in uranium dioxide samples. Detection limits are as low as 10 μg. 1.6 This test method covers the determination of nitride nitrogen in uranium dioxide in the range from 10 to 250 μg. 1.7 This test method covers the spectrographic analysis of nuclear-grade UO2 for the 26 elements in the ranges indicated in Table 2. 1.8 For simultaneous determination of trace ele...
Gareev, F. A.; Zhidkova, I. E.
2007-03-01
We come to the conclusion that all atomic models based on either the Newton equation and the Kepler laws, or the Maxwell equations, or the Schrodinger and Dirac equations are in reasonable agreement with experimental data. We can only suspect that these equations are grounded on the same fundamental principle(s) which is (are) not known or these equations can be transformed into each other. We proposed a new mechanism of LENR: cooperative processes in the whole system nuclei + atoms + condensed matter - nuclear reactions in plasma - can occur at smaller threshold energies than the corresponding ones on free constituents. We were able to quantize phenomenologically the first time the differences between atomic and nuclear rest masses by the formula: δδM =n1/n2 X 0.0076294 (in MeV/ c^2), ni=1,2,3,.... Note that this quantization rule is justified for atoms and nuclei with different A, N and Z and the nuclei and atoms represent a coherent synchronized systems - a complex of coupled oscillators (resonators). The cooperative resonance synchronization mechanisms can explain how electron volt (atomic-) scale processes can induce and control nuclear MeV (nuclear-) scale processes and reactions., F.A. Gareev, I.E. Zhidkova, E-print arXiv Nucl-th/ 0610002 2006.
International Nuclear Information System (INIS)
Tarantin, N.I.
2001-01-01
Data on nuclear masses provide a basis for creating and testing various nuclear models. A tandem system of FLNR comprised of the U-400M cyclotron, the COMBAS magnetic separator and the mass-spectrometric ion trap of an 'in-flight capture' type is considered as a possible complex for producing of the short-lived nuclei in fragmentation reactions by heavy ions and for precise mass measurement of these nuclei. The plan of scientific and technical FLNR research includes a project DRIBs for producing beams of accelerated radioactive nuclear reaction products and photofission fragments. This project proposes also precise mass measurements of the fission fragment with the help of the ion trap. The in-flight entrance of the ions and their capture in the mass-spectrometric ion trap using the monochromatizing degrader, the static electric and magnetic fields and a new invention, a magnetic unidirectional transporting ventil, is considered
Roh, Hwasung; Lee, Huseok; Lee, Jong Seh
2013-06-01
In this study, a new lumped-mass-stick model (LMSM) is developed based on the modal characteristics of a structure such as eigenvalues and eigenvectors. The simplified model, named the "frequency adaptive lumped-massstick model," hasonly a small number of stick elements and nodes to provide the same natural frequencies of the structure and is applied to a nuclear containment building. To investigate the numerical performance of the LMSM, a time history analysis is carried out on both the LMSM and the finite element model (FEM) for a nuclear containment building. A comparison of the results shows that the dynamic responses of the LMSM in terms of displacement and acceleration are almost identical to those of the FEM. In addition, the results in terms of fl oor response spectra at certain elevations are also in good agreement.
International Nuclear Information System (INIS)
1994-12-01
The design process for determining the mass increase for the substitution of low-enriched uranium (LEU) for high-enriched uranium (HEU) in space nuclear reactor systems is an optimization process which must simultaneously consider several variables. This process becomes more complex whenever the reactor core operates on an in-core thermionic power conversion, in which the fissioning of the nuclear fuel is used to directly heat thermionic emitters, with the subsequent elimination of external power conversion equipment. The increased complexity of the optimization process for this type of system is reflected in the work reported herein, where considerably more information has been developed for the moderated in-core thermionic reactors
International Nuclear Information System (INIS)
Betti, M.; Rasmussen, G.; Hiernaut, T.; Koch, L.
1994-01-01
A VG9000 glow discharge mass spectrometer has been modified for the direct analysis of solid nuclear samples within a glove-box environment. Because containment is needed for the analysis of this kind of material, the glove-box encloses all parts of the instrument that come into contact with the sample, namely the ion source chamber, sample interlock and associated pumping system. External modifications eliminate outside contamination by the fitting of absolute filters on all source supplies. Internally the design of the ion source has been altered to minimize the number of operations performed inside the glove-box thereby simplifying operation and routine maintenance. These modifications retain the ion extraction and focusing properties of the instrument. The data presented show that there is no compromise in the analytical performance of the instrument when placed in the glove-box. Data representative of nuclear materials is also shown. (Author)
Regnier, D.; Dubray, N.; Schunck, N.; Verrière, M.
2016-05-01
Background: Accurate knowledge of fission fragment yields is an essential ingredient of numerous applications ranging from the formation of elements in the r process to fuel cycle optimization for nuclear energy. The need for a predictive theory applicable where no data are available, together with the variety of potential applications, is an incentive to develop a fully microscopic approach to fission dynamics. Purpose: In this work, we calculate the pre-neutron emission charge and mass distributions of the fission fragments formed in the neutron-induced fission of 239Pu using a microscopic method based on nuclear density functional theory (DFT). Methods: Our theoretical framework is the nuclear energy density functional (EDF) method, where large-amplitude collective motion is treated adiabatically by using the time-dependent generator coordinate method (TDGCM) under the Gaussian overlap approximation (GOA). In practice, the TDGCM is implemented in two steps. First, a series of constrained EDF calculations map the configuration and potential-energy landscape of the fissioning system for a small set of collective variables (in this work, the axial quadrupole and octupole moments of the nucleus). Then, nuclear dynamics is modeled by propagating a collective wave packet on the potential-energy surface. Fission fragment distributions are extracted from the flux of the collective wave packet through the scission line. Results: We find that the main characteristics of the fission charge and mass distributions can be well reproduced by existing energy functionals even in two-dimensional collective spaces. Theory and experiment agree typically within two mass units for the position of the asymmetric peak. As expected, calculations are sensitive to the structure of the initial state and the prescription for the collective inertia. We emphasize that results are also sensitive to the continuity of the collective landscape near scission. Conclusions: Our analysis confirms
International Nuclear Information System (INIS)
Silva Neto, A.J. da; Alvim, A.C.M.
1989-01-01
This work describes the thermalhydraulics code CROSS, designed for micro-computer calculation of heat and mass flow distributions in LWR nuclear reactor cores using the Hardy Cross method. Equations to calculate the pressure variations in the coolant channels are presented, along with derivation of a linear system of equations to calculate the energy balance. This system is solved through the Benachievicz method. A case study is presented, showing that the methodology developed in this work can be used in place of the forward marching multi-channel codes. (author) [pt
International Nuclear Information System (INIS)
Abdrahmanov, J.; Tsai, E.; Zaitsev, V.; Mamadaliev, S.; Popov, L.; Sukurov, B.
1996-01-01
Objectives of the project: The first objective is clearing of state of immune system of humans exposed to gamma radiation during long period of their life in Semipalatinsk province. The second objective is establishing relations between type of disorders of immune system and rate of particular diseases. The third objective is development of method of the treatment of immuno deficits via plasmaphaeresis in residents with postradiation immune disorders. Scientific and technical approaches based on following tasks: Completing of large scale examination of immune system of residents of Semipalatinsk province Evaluating of immuno deficit's types of people affected from consequences of nuclear explosions in Semipalatinsk polygon Analysis of diseases rates and evaluating of correlation between particular diseases and type of immune disorders Development of rehabilitation methods in experimental animals exposed to different radiation dose during different period of time Development of experimental model of main postradiation immuno deficits and analysis of morbidity linked with immune disorders Experimental trial of plasmaphaeresis and analysis of morbidity changes in animals Clinical trial of plasmaphaeresis in patients with postradiation immuno deficits and analysis clinical responses Project will use: histochemical assay for identification of main subpopulations of T lymphocytes immunochemical assay for evaluated of serum concentration of immunoglobulins of types A,M,G dosimetric methods, limited gamma radiation of experimental animals, computerized data processing experimental and clinical trials using plasmaphaeresis. Possible results: The project will evaluate of characters and types of postradiation T immuno deficits and their correlation with definite diseases, which can be geographic health problem for regions polluted with radioactive wastes. Also, a new methods for determination of T immuno deficit will be developed. Existed data, concerning to project from
International Nuclear Information System (INIS)
Queipo-Ruiz, J.; Guzman-Martinez, F.; Rodriguez-Hoyos, O.
2011-01-01
The level density parameter is a very important ingredient in statistic study of nuclear reaction, it has been studied to low energies excitation E < 2MeV where it values is approximately constant, experimental results to energies of excitation more than 2 MeV has been obtained of evaporation spectrum, to nuclei with A=160. In this work we present a calculation of densities level parameter, for a wide range of mass and temperature, taking in accounts the shell effects and the mass effective interaction. The result has been carried out within the semi classical approximation, for the single particle level densities. We results have a reasonable agreement with the experimental data available. (Author)
Direct Energy Conversion for Nuclear Propulsion at Low Specific Mass Project
National Aeronautics and Space Administration — Low specific mass (< 3 kg/kW) in-space electric power and propulsion can drastically alter the paradigm for exploration of the Solar System, changing human...
Mass extraction rates of radionuclides in fallout material from a 170-kt nuclear crater
Energy Technology Data Exchange (ETDEWEB)
Fleming, E H [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)
1969-07-01
The quantity k is defined as the fraction of a nuclide in the environment which must be ingested each day over a given time period to receive a maximum allowable dose, in accordance with the International Commission on Radiological Protection guidelines. Values of k were computed for radionuclides produced in a single cratering detonation using current design technology. A new concept, called the 'Mass Extraction Rate,' is presented. This concept is defined as the mass of earth material from which the entire quantity of the radionuclide must be extracted and ingested each day by some natural process over a given time interval, which results in a permissible dose. Mass Extraction Rate values are tabulated. A comparison is made between the Mass Extraction Rate and the specific activity methods. (author)
Mass extraction rates of radionuclides in fallout material from a 170-kt nuclear crater
International Nuclear Information System (INIS)
Fleming, E.H.
1969-01-01
The quantity k is defined as the fraction of a nuclide in the environment which must be ingested each day over a given time period to receive a maximum allowable dose, in accordance with the International Commission on Radiological Protection guidelines. Values of k were computed for radionuclides produced in a single cratering detonation using current design technology. A new concept, called the 'Mass Extraction Rate,' is presented. This concept is defined as the mass of earth material from which the entire quantity of the radionuclide must be extracted and ingested each day by some natural process over a given time interval, which results in a permissible dose. Mass Extraction Rate values are tabulated. A comparison is made between the Mass Extraction Rate and the specific activity methods. (author)
The origin of nuclear mass number dependence in EMC-effect
International Nuclear Information System (INIS)
Kurihara, Y.; Date, S.; Nakamura, A.; Sato, H.; Sumiyoshi, H.; Yoshinada, K.
1985-03-01
The origin of the mass number dependence of the nucleon structure functions extracted from the deep inelastic lepton-nucleus scattering is investigated by factorizing the structure function into A and x dependent parts. It is found that the mass number dependence is determined by the probability of exotic components in multi-nucleon overlap. This suggests that the deformation of the nucleon structure function is caused by the interaction among nucleons during their overlap. (author)
The effect of nuclear gas distribution on the mass determination of supermassive black holes
Mejía-Restrepo, J. E.; Lira, P.; Netzer, H.; Trakhtenbrot, B.; Capellupo, D. M.
2018-01-01
Supermassive black holes reside in the nuclei of most galaxies. During their active episodes, black holes are powered by accretion discs where gravitational energy is converted into radiation1. Accurately determining black hole masses is key to understand how the population evolves over time and how the black holes relate to their host galaxies2-4. Beyond the local universe, z ≳ 0.2, the mass is commonly estimated assuming a virialized motion of gas in the close vicinity of the active black holes, traced through broad emission lines5,6. However, this procedure has uncertainties associated with the unknown distribution of the gas clouds. Here, we show that the black hole masses derived from the properties of the accretion disk and virial mass estimates differ by a factor that is inversely proportional to the width of the broad emission lines. This leads to virial mass misestimations up to a factor of six. Our results suggest that a planar gas distribution that is inclined with respect to the line of sight may account for this effect. However, radiation pressure effects on the distribution of gas can also reproduce our results. Regardless of the physical origin, our findings contribute to mitigating the uncertainties in current black hole mass estimations and, in turn, will help us to better understand the evolution of distant supermassive black holes and their host galaxies.
International Nuclear Information System (INIS)
Gareev, F.A.; Zhidkova, I.E.; )
2007-01-01
Full text: We come to the conclusion that all atomic models based on either the Newton equation and the Kepler laws, or the Maxwell equations, or the Schroedinger and Dirac equations are in reasonable agreement with experimental data. We can only suspect that these equations are grounded on the same fundamental principles which are not known or these equations can be transformed into each other. We proposed a new mechanism of LENR: cooperative processes in the whole system - nuclei + atoms + condensed matter - nuclear reactions in plasma - can occur at smaller threshold energies than the corresponding ones on free constituents. We were able to quantize phenomenologically the first time the differences between atomic and nuclear rest masses by the formula: ΔΔM = n 1 /n 2 ·0.0076294 (in MeV/ ), n i =1,.2,3... Note that this quantization rule is justified for atoms and nuclei with different A, N and Z and the nuclei and atoms represent a coherent synchronized open systems - a complex of coupled oscillators (resonators). The cooperative resonance synchronization mechanisms are responsible for explanation of how the electron volt world can influence on the nuclear mega electron volt world. It means that we created new possibilities for inducing and controlling nuclear reactions by atomic processes grounded on the fundamental low of physics - conservation law of energy. The results of these research field can provide new ecologically pure mobile sources of energy independent from oil, gas and coal, new substances, and technologies. For example, this discovery gives us a simple and cheep method for utilization of nuclear waste
International Nuclear Information System (INIS)
Guigues, E.; Janulyte, A.; Zerega, Y.; Pontillon, Y.
2013-06-01
The work presented in this paper has been performed in the framework of a joint research program between Aix-Marseille University and CEA Cadarache. The aim is to develop a mass spectrometer (MS) device for the MERARG facility. MERARG is devoted to the study of fission gas release measurement, from nuclear fuels submitted to annealing tests in high activity laboratory such as LECA-STAR, thanks to gamma spectrometry. The mass spectrometer will then extend the measurement capability from the γ-emitters gases to all the gases involved in the release in order to have a better understanding of the fission gas release dynamics from fuel during thermal transients. Furthermore, the mass spectrometer instrument combines the capabilities and performances of both on-line (for release kinetic) and off-line implementations (for delayed accurate analysis of capacities containing total release gas). The paper deals with two main axes: (1) the modelling of gas sampling inlet device and its performance and (2) the first MS qualification/calibration results. The inlet device samples the gas and also adapts the pressure between MERARG sweeping line at 1.2 bar and mass spectrometer chamber at high vacuum. It is a two-stage device comprising a capillary at inlet, an intermediate vacuum chamber, a molecular leak inlet and a two-stage pumping device. Pressure drops, conductance and throughputs are estimated both for mass spectrometer operation and for exhaust gas recovery. Possible gas segregation is also estimated and device modification is proposed to attain a more accurate calibration. First experimental results obtained from a standard gas bottle show that the quantitative analysis at a few ppm level can be achieved for all isotopes of Kr and Xe, as well as masses 2 and 4 u. (authors)
Nuclear triaxiality in the A ∼ 160–170 mass region: the story so far
Indian Academy of Sciences (India)
2014-11-01
Nov 1, 2014 ... 1Nuclear Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085, India ... According to the calculated shell gaps, among Lu isotopes, 165Lu94 and 168Lu97 .... Based on a systematic investigation of the .... A brief review of recent discoveries and ongoing experimental and theoretical investi-.
The mass media role in acceptance activities of Slovak Republic's Nuclear Regulatory Authority
International Nuclear Information System (INIS)
Seliga, Mojmir
1998-01-01
Communication is the vital link between Nuclear Regulatory Authority and the public. If people do not know and understand the facts on which optimal a safety energy choice decisions should be based they cannot make informed decisions on how their own objectives can be met. The following ten commandments of communications are pointed out: be yourself; be comfortable and confident; be honest; be brief; be human; be personal; be positive and consistent; be attentive; be energetic; be committed and sincere. The important aspect is to test whether the nuclear energy in the Slovak Republic is acceptable according to mandatory rules and if its operation is regulated by the state through the independent institution - the Nuclear Regulatory Authority of the Slovak Republic (UJD). The media in Slovakia has on important power. Many organizations are therefore apprehensive when dealing with the press, radio and television. Many people would simply prefer not to get panicked when the dreaded microphones and cameras do appear. UJD considers the whole area of public relations as an essential component of its activity. UJD intends to offer the public true, systematic, qualified, understandable and independent information, regarding the safety of nuclear power plants, as well as regarding the methods and results of UJD work. Generally, public information is considered a significant contribution to the creation of confidence into the regulatory work. The paper presents the UJD communication program and relations with media as well as the preparedness of public information in case of emergency
Energy Technology Data Exchange (ETDEWEB)
Billon, J P [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes
1970-07-01
Some of basic principles in spark source mass spectrometry are recalled. It is shown how this method can lead to quantitative analysis when attention is paid to some theoretical aspects. A time constant relation being assumed between the analysed solid sample and the ionic beam it gives we determined experimental relative sensitivity factors for impurities in uranium matrix. Results being in fairly good agreement with: an unelaborate theory on ionization yield in spark-source use of theoretically obtained relative sensitivity factors in uranium matrix has been developed. (author) [French] Apres avoir rappele quelques principes fondamentaux regissant la spectrometrie de masse a etincelles, nous avons montre que moyennant un certain nombre de precautions, il etait possible d'utiliser cette methode en analyse quantitative. Ayant admis qu'il existait une relation constante dans le temps entre l'echantillon solide analyse et le faisceau ionique qui en est issu, nous avons d'abord entrepris de determiner des coefficients de correction experimentaux pour des matrices d'uranium. Les premiers resultats pratiques semblant en accord avec une theorie simple relative au rendement d'ionisation dans la source a etincelles, nous avons etudie la possibilite d'appliquer directement les coefficients theoriques ainsi definis, l'application etant toujours faite sur des matrices d'uranium. (auteur)
Determination of burn-up of irradiated nuclear fuels using mass spectrometry
International Nuclear Information System (INIS)
Jagadish Kumar, S.; Telmore, V.M.; Shah, R.V.; Sasi Bhushan, K.; Paul, Sumana; Kumar, Pranaw; Rao, Radhika M.; Jaison, P.G.
2017-01-01
Burn-up defined as the atom percent fission, is a vital parameter used for assessing the performance of nuclear fuel during its irradiation in the reactor. Accurate data on the actinide isotopes are also essential for the reliable accountability of nuclear materials and for nuclear safeguards. Both destructive and non-destructive methods are employed in the post-irradiation analysis for the burn-up measurements. Though non-destructive methods are preferred from the point view of remote handling of irradiated fuels with high radioactivity, they do not provide the high accuracy as achieved by the chemical analysis methods. Thus destructive radiochemical and chemical analyses are still the established reference methods for accurate and reliable burn-up determination of irradiated nuclear fuels. In the destructive method, burn-up of irradiated nuclear fuel is determined by correlating the amount of a fission product formed during irradiation with that of heavy elements. Thus the destructive experimental determination of burn-up involves the dissolution of irradiated fuel samples followed by the separation and determination of heavy elements and fission product(s) to be used as burn-up monitor(s). Another approach for the experimental determination of burn-up is based on the changes in the abundances of the heavy element isotopes. A widely accepted method for burn-up determination is based on stable "1"4"8Nd and "1"3"9La as burn-up monitors. Several properties such as non-volatility, nearly same yields for thermal fissions of "2"3"5U and "2"3"9Pu etc justifies the selection of "1"4"8Nd as a burn-up monitor
ICT: isotope correction toolbox.
Jungreuthmayer, Christian; Neubauer, Stefan; Mairinger, Teresa; Zanghellini, Jürgen; Hann, Stephan
2016-01-01
Isotope tracer experiments are an invaluable technique to analyze and study the metabolism of biological systems. However, isotope labeling experiments are often affected by naturally abundant isotopes especially in cases where mass spectrometric methods make use of derivatization. The correction of these additive interferences--in particular for complex isotopic systems--is numerically challenging and still an emerging field of research. When positional information is generated via collision-induced dissociation, even more complex calculations for isotopic interference correction are necessary. So far, no freely available tools can handle tandem mass spectrometry data. We present isotope correction toolbox, a program that corrects tandem mass isotopomer data from tandem mass spectrometry experiments. Isotope correction toolbox is written in the multi-platform programming language Perl and, therefore, can be used on all commonly available computer platforms. Source code and documentation can be freely obtained under the Artistic License or the GNU General Public License from: https://github.com/jungreuc/isotope_correction_toolbox/ {christian.jungreuthmayer@boku.ac.at,juergen.zanghellini@boku.ac.at} Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Gallego, Eduardo; Cantone, Marie Claire; Oughton, Deborah H; Perko, Tanja; Prezelj, Iztok; Tomkiv, Yevgeniya
2017-04-01
This paper presents the results of a large study of 1340 articles published by two major newspapers in six European countries (Belgium, Italy, Norway, Slovenia, Spain and Russia) in the first 2 months after the Fukushima Daiichi nuclear disaster. The focus of the analysis is on the application and overall impact of protective actions, both during the emergency phase and later, how the newspapers describe those actions, which differences were apparent between countries and what recommendations can be extracted in order to improve general communication about these issues. A clear lesson is that, even under uncertainty and recognising limitations, responsible authorities need to provide transparent, clear and understandable information to the public and the mass media right from the beginning of the early phase of any nuclear emergency. Clear, concise messages should be given. Mass media could play a key role in reassuring the public if the countermeasures are clearly explained. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Gourgiotis, Alkiviadis; Ducasse, Thomas; Barker, Evelyne; Jollivet, Patrick; Gin, Stéphane; Bassot, Sylvain; Cazala, Charlotte
2017-02-15
High-level, long-lived nuclear waste arising from spent fuel reprocessing is vitrified in silicate glasses for final disposal in deep geologic formations. In order to better understand the mechanisms driving glass dissolution, glass alteration studies, based on silicon isotope ratio monitoring of 29 Si-doped aqueous solutions, were carried out in laboratories. This work explores the capabilities of the new type of quadrupole-based ICP-MS, the Agilent 8800 tandem quadrupole ICP-MS/MS, for accurate silicon isotope ratio determination for alteration studies of nuclear waste glasses. In order to avoid silicon polyatomic interferences, a new analytical method was developed using O 2 as the reaction gas in the Octopole Reaction System (ORS), and silicon isotopes were measured in mass-shift mode. A careful analysis of the potential polyatomic interferences on SiO + and SiO 2 + ion species was performed, and we found that SiO + ion species suffer from important polyatomic interferences coming from the matrix of sample and standard solutions (0.5M HNO 3 ). For SiO 2 + , no interferences were detected, and thus, these ion species were chosen for silicon isotope ratio determination. A number of key settings for accurate isotope ratio analysis like, detector dead time, integration time, number of sweeps, wait time offset, memory blank and instrumental mass fractionation, were considered and optimized. Particular attention was paid to the optimization of abundance sensitivity of the quadrupole mass filter before the ORS. We showed that poor abundance sensitivity leads to a significant shift of the data away from the Exponential Mass Fractionation Law (EMFL) due to the spectral overlaps of silicon isotopes combined with different oxygen isotopes (i.e. 28 Si 16 O 18 O + , 30 Si 16 O 16 O + ). The developed method was validated by measuring a series of reference solutions with different 29 Si enrichment. Isotope ratio trueness, uncertainty and repeatability were found to be
Energy Technology Data Exchange (ETDEWEB)
Gourgiotis, Alkiviadis, E-mail: alkiviadis.gourgiotis@irsn.fr [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-DGE/SRTG/LT2S, Fontenay-aux-Roses (France); Ducasse, Thomas [CEA, DEN, DTCD, SECM, F-30207 Bagnols-sur-Cèze (France); Barker, Evelyne [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-DGE/SRTG/LT2S, Fontenay-aux-Roses (France); Jollivet, Patrick; Gin, Stéphane [CEA, DEN, DTCD, SECM, F-30207 Bagnols-sur-Cèze (France); Bassot, Sylvain; Cazala, Charlotte [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-DGE/SRTG/LT2S, Fontenay-aux-Roses (France)
2017-02-15
High-level, long-lived nuclear waste arising from spent fuel reprocessing is vitrified in silicate glasses for final disposal in deep geologic formations. In order to better understand the mechanisms driving glass dissolution, glass alteration studies, based on silicon isotope ratio monitoring of {sup 29}Si-doped aqueous solutions, were carried out in laboratories. This work explores the capabilities of the new type of quadrupole-based ICP-MS, the Agilent 8800 tandem quadrupole ICP-MS/MS, for accurate silicon isotope ratio determination for alteration studies of nuclear waste glasses. In order to avoid silicon polyatomic interferences, a new analytical method was developed using O{sub 2} as the reaction gas in the Octopole Reaction System (ORS), and silicon isotopes were measured in mass-shift mode. A careful analysis of the potential polyatomic interferences on SiO{sup +} and SiO{sub 2}{sup +} ion species was performed, and we found that SiO{sup +} ion species suffer from important polyatomic interferences coming from the matrix of sample and standard solutions (0.5M HNO{sub 3}). For SiO{sub 2}{sup +}, no interferences were detected, and thus, these ion species were chosen for silicon isotope ratio determination. A number of key settings for accurate isotope ratio analysis like, detector dead time, integration time, number of sweeps, wait time offset, memory blank and instrumental mass fractionation, were considered and optimized. Particular attention was paid to the optimization of abundance sensitivity of the quadrupole mass filter before the ORS. We showed that poor abundance sensitivity leads to a significant shift of the data away from the Exponential Mass Fractionation Law (EMFL) due to the spectral overlaps of silicon isotopes combined with different oxygen isotopes (i.e. {sup 28}Si{sup 16}O{sup 18}O{sup +}, {sup 30}Si{sup 16}O{sup 16}O{sup +}). The developed method was validated by measuring a series of reference solutions with different {sup 29}Si
Aymard, François; Gulminelli, Francesca; Margueron, Jérôme
2016-08-01
We have recently addressed the problem of the determination of the nuclear surface energy for symmetric nuclei in the framework of the extended Thomas-Fermi (ETF) approximation using Skyrme functionals. We presently extend this formalism to the case of asymmetric nuclei and the question of the surface symmetry energy. We propose an approximate expression for the diffuseness and the surface energy. These quantities are analytically related to the parameters of the energy functional. In particular, the influence of the different equation of state parameters can be explicitly quantified. Detailed analyses of the different energy components (local/non-local, isoscalar/isovector, surface/curvature and higher order) are also performed. Our analytical solution of the ETF integral improves previous models and leads to a precision of better than 200 keV per nucleon in the determination of the nuclear binding energy for dripline nuclei.
2015-06-01
woman I know. She is the true cornerstone of my career. Through the tribulations of deployments and long hours in port, she steadily provided me...right diagram (b), shows an odd isotope with the nuclear spin angular momenta of I = 3/2. In contrast with the even isotope, there is two states, F...The electron spin angular momentum is not affected by the dipole operator. The even isotopes have equal squares of their Clebsch-Gordan
New measurement capabilities of mass spectrometry in the nuclear fuel cycle
International Nuclear Information System (INIS)
Perrin, R.E.
1979-01-01
Three recent developments, when combined, have the potential for greatly improving accountability measurements in the nuclear fuel cycle. The techniques are particularly valuable when measuring the contents of vessels which are difficult to calibrate by weight or volume. Input dissolver accountability measurements, inparticular, benefit from the application of these techniques. Los Alamos Scientific Laboratory has developed the capability for isotopic analysis of U and Pu samples at the nanogram level with an accuracy of 0.1 relative %. The Central Bureau for Nuclear Materials Measurement in Geel, Belgium has developed the capability of preparing mixed, solid metal U and Pu spikes with an accuracy of better than 0.1 relative %. Idaho Nuclear Energy Laboratory and C.K. Mathews at Bhabha Atomic Research have demonstrated a technique for determining the ratio of sample size to total solution measured which is independent of both the weight and the volume of the solution being measured. The advantages and limitations of these techniques are discussed. An analytical scheme which takes advantage of the special features of these techniques is proposed. 4 refs
Ordenes-Briceño, Yasna; Puzia, Thomas H.; Eigenthaler, Paul; Taylor, Matthew A.; Muñoz, Roberto P.; Zhang, Hongxin; Alamo-Martínez, Karla; Ribbeck, Karen X.; Grebel, Eva K.; Ángel, Simón; Côté, Patrick; Ferrarese, Laura; Hilker, Michael; Lançon, Ariane; Mieske, Steffen; Miller, Bryan W.; Rong, Yu; Sánchez-Janssen, Ruben
2018-06-01
We present the analysis of 61 nucleated dwarf galaxies in the central regions (≲R vir/4) of the Fornax galaxy cluster. The galaxies and their nuclei are studied as part of the Next Generation Fornax Survey using optical imaging obtained with the Dark Energy Camera mounted at Blanco/Cerro Tololo Inter-American Observatory and near-infrared data obtained with VIRCam at VISTA/ESO. We decompose the nucleated dwarfs in nucleus and spheroid, after subtracting the surface brightness profile of the spheroid component and studying the nucleus using point source photometry. In general, nuclei are consistent with colors of confirmed metal-poor globular clusters, but with significantly smaller dispersion than other confirmed compact stellar systems in Fornax. We find a bimodal nucleus mass distribution with peaks located at {log}({{ \\mathcal M }}* /{M}ȯ )≃ 5.4 and ∼6.3. These two nucleus subpopulations have different stellar population properties: the more massive nuclei are older than ∼2 Gyr and have metal-poor stellar populations (Z ≤ 0.02 Z ⊙), while the less massive nuclei are younger than ∼2 Gyr with metallicities in the range 0.02 < Z/Z ⊙ ≤ 1. We find that the nucleus mass ({{ \\mathcal M }}nuc}) versus galaxy mass ({{ \\mathcal M }}gal}) relation becomes shallower for less massive galaxies starting around 108 M ⊙, and the mass ratio {η }n={{ \\mathcal M }}nuc}/{{ \\mathcal M }}gal} shows a clear anticorrelation with {{ \\mathcal M }}gal} for the lowest masses, reaching 10%. We test current theoretical models of nuclear cluster formation and find that they cannot fully reproduce the observed trends. A likely mixture of in situ star formation and star cluster mergers seems to be acting during nucleus growth over cosmic time.
International Nuclear Information System (INIS)
Deron, S.; )
1996-01-01
Gravimetry, titration, coulometry and isotope dilution mass spectrometry are alternative techniques which can be used to obtain elemental assays of the desirable accuracy. The communication briefly describes the characteristics of the procedure and summarizes a wealth of experience accumulated during actual accountability verification activities
International Nuclear Information System (INIS)
KLEM, M.J.
2000-01-01
The purpose of these calculations is to develop the material balances for documentation of the Canister Storage Building (CSB) Process Flow Diagram (PFD) and future reference. The attached mass balances were prepared to support revision two of the PFD for the CSB. The calculations refer to diagram H-2-825869
International Nuclear Information System (INIS)
KLEM, M.J.
2000-01-01
The purpose of this calculation document is to develop the bases for the material balances of the Multi-Canister Overpack (MCO) Level 1 Process Flow Diagram (PFD). The attached mass balances support revision two of the PFD for the MCO and provide future reference
Determination of nuclear fuel burn-up using mass spectrometric techniques
International Nuclear Information System (INIS)
Saha, B.; Bagyalakshmi, R.; Periaswami, G.; Kavimandan, V.D.; Chitambar, S.A.; Jain, H.C.; Mathews, C.K.
1977-01-01
Determination of burn-up using a stable fission product monitor such as 148 Nd and heavy elements, determined by isotope dilution mass spectrometry gives the most accurate data. This report describes the work carried out to standardise the conditions for burn-up determination. Some typical results are given. (author)
Energy Technology Data Exchange (ETDEWEB)
Tanikawa, Ataru; Sato, Yushi; Hachisu, Izumi [Department of Earth Science and Astronomy, College of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Nomoto, Ken’ichi; Maeda, Keiichi [Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Nakasato, Naohito, E-mail: tanikawa@ea.c.u-tokyo.ac.jp [Department of Computer Science and Engineering, University of Aizu, Tsuruga Ikki-machi Aizu-Wakamatsu, Fukushima 965-8580 (Japan)
2017-04-20
We investigate nucleosynthesis in tidal disruption events (TDEs) of white dwarfs (WDs) by intermediate-mass black holes. We consider various types of WDs with different masses and compositions by means of three-dimensional (3D) smoothed particle hydrodynamics (SPH) simulations. We model these WDs with different numbers of SPH particles, N , from a few 10{sup 4} to a few 10{sup 7} in order to check mass resolution convergence, where SPH simulations with N > 10{sup 7} (or a space resolution of several 10{sup 6} cm) have unprecedentedly high resolution in this kind of simulation. We find that nuclear reactions become less active with increasing N and that these nuclear reactions are excited by spurious heating due to low resolution. Moreover, we find no shock wave generation. In order to investigate the reason for the absence of a shock wave, we additionally perform one-dimensional (1D) SPH and mesh-based simulations with a space resolution ranging from 10{sup 4} to 10{sup 7} cm, using a characteristic flow structure extracted from the 3D SPH simulations. We find shock waves in these 1D high-resolution simulations, one of which triggers a detonation wave. However, we must be careful of the fact that, if the shock wave emerged in an outer region, it could not trigger the detonation wave due to low density. Note that the 1D initial conditions lack accuracy to precisely determine where a shock wave emerges. We need to perform 3D simulations with ≲10{sup 6} cm space resolution in order to conclude that WD TDEs become optical transients powered by radioactive nuclei.
International Nuclear Information System (INIS)
Fifield, L.K.; Hausladen, P.A.; Cresswell, R.G.; Di Tada, M.L.; Day, J.P.; Carling, R.S.; Oughton, D.H.
1999-01-01
Historical discharges of plutonium from the Russian nuclear processing plant at Mayak in the Urals have been traced in sediments, soils and river water using ultra-sensitive detection of plutonium isotopes by accelerator mass spectrometry (AMS). Significant advantages of AMS over other techniques are its very high sensitivity. which is presently ∼10 6 atoms (1 μBq), and its ability to determine the 240 Pu/ 239 Pu ratio. The latter is a sensitive indicator of the source of the plutonium, being very low (1-2%) for weapons grade plutonium, and higher (∼ 20%) for plutonium from civil reactors or fallout from nuclear weapons testing. Since this ratio has changed significantly over the years of discharges from Mayak, a measurement can provide important information about the source of plutonium at a particular location. Similar measurements have been performed on samples from the Kara Sea which contains a graveyard of nuclear submarines from the former Soviet Union. AMS techniques have also been developed for detection of 99 Tc down to levels of a few femtograms. This isotope is one of the most prolific fission products and has a very long half-life of 220 ka. Hundreds of kg have been discharged from the nuclear reprocessing plant at Sellafield in the UK. While there may be public health issues associated with these discharges which can be addressed with AMS, these discharges may also constitute a valuable oceanographic tracer experiment in this climatically-important region of the world's oceans. Applications to date have included a human uptake study to assess long-term retention of 99 Tc in the body, and a survey of seaweeds from northern Europe to establish a baseline for a future oceanographic study
International Nuclear Information System (INIS)
Prasad, Mahendra; Gaikwad, Avinash J.; Sridharan, Arunkumar; Parida, Smrutiranjan
2015-01-01
The flow of fluid in pipes cause corrosion wherein the inner surface of pipe becomes progressively thinner and susceptible to failure. This form of corrosion dependent on flow dynamics is called Flow Accelerated Corrosion (FAC) and has been observed in Nuclear Power Plants (NPPs). Mass transfer coefficient (MTC) is related to extent of wall thinning and it changes from its value in a straight pipe (with same fluid parameters) for flow in orifices, bends, junctions etc. due to gross disturbance of the velocity profile. This paper presents two-dimensional computational fluid dynamics (CFD) simulations for an orifice configuration in a straight pipe. Turbulent model K- ω with shear stress transport and transition flow was the model used for simulation studies. The mass transfer boundary layer (MTBL) thickness δ mtbl is related to the Schmidt number (Sc) and hydrodynamic boundary layer thickness δ h , as δ mtbl ~ δh/(Sc 1/3 ). MTBL is significantly smaller than δ h and hence boundary layer meshing was carried out deep into δ mtbl . Uniform velocity profile was applied at the inlet. Post orifice fluid shows large recirculating flows on the upper and lower wall. At various locations after orifice, mass transfer coefficient is calculated and compared with the value in straight pipe with fully developed turbulent flow. The MTC due to the orifice increases and it is correlated with enhanced FAC in region after orifice. (author)
International Nuclear Information System (INIS)
Nottoli, Emmanuelle; Bourlès, Didier; Bienvenu, Philippe; Labet, Alexandre; Arnold, Maurice; Bertaux, Maité
2013-01-01
The radiological characterisation of nuclear waste is essential for managing storage sites. Determining the concentration of Long‐Lived RadioNuclides (LLRN) is fundamental for their long-term management. This paper focuses on the measurement of low 41 Ca concentrations in ions exchange resins used for primary fluid purification in Pressurised Water Reactors (PWR). 41 Ca concentrations were successfully measured by Accelerator Mass Spectrometry (AMS) after the acid digestion of resin samples, followed by radioactive decontamination and isobaric suppression through successive hydroxide, carbonate, nitrate and final CaF 2 precipitations. Measured 41 Ca concentrations ranged from 0.02 to 0.03 ng/g, i.e. from 0.06 to 0.09 Bq/g. The 41 Ca/ 60 Co activity ratios obtained were remarkably reproducible and in good agreement with the current ratio used for resins management. - Highlights: • In the context of radioactive waste management, this study aimed at measuring 41 Ca in spent resins using Accelerator Mass Spectrometry. • A chemical treatment procedure was developed to quantitatively recover calcium in solution and selectively extract it. • Developed firstly on synthetic matrices, the chemical treatment procedure was then successfully applied to real resin samples. • Accelerator mass spectrometry allowed measuring concentrations of 41 Ca in spent resins as low as 0.02 ng/g of dry resin. • Final results are in agreement with current data used for spent resins management
Aymard, François; Gulminelli, Francesca; Margueron, Jérôme
2016-08-01
The problem of determination of nuclear surface energy is addressed within the framework of the extended Thomas Fermi (ETF) approximation using Skyrme functionals. We propose an analytical model for the density profiles with variationally determined diffuseness parameters. In this first paper, we consider the case of symmetric nuclei. In this situation, the ETF functional can be exactly integrated, leading to an analytical formula expressing the surface energy as a function of the couplings of the energy functional. The importance of non-local terms is stressed and it is shown that they cannot be deduced simply from the local part of the functional, as it was suggested in previous works.
Analysis of heat and mass transport processes near an emplaced nuclear waste canister
International Nuclear Information System (INIS)
Keller, C.
1990-01-01
A review has been performed of the models and experimental plans for evaluation of the spent fuel canister environment in a nuclear repository, e.g., the planned Yucca Mountain facilities. Special emphasis was placed on the relevance of the models and experiments to the 100 to 10,000 year prediction. The question was addressed whether one could justify testing in materials other than Yucca Mountain rock and obtain results in a relatively short time which would be relevant to the long time in Yucca Mountain. The paper discusses steam evolution in calculations and experiments, fracture models, possible measurements of relative permeability, and long time scale effects. 5 figs. (MB)
International Nuclear Information System (INIS)
Loche, F.
2006-10-01
In the framework of radioactive waste drums control, difficulties arise in the nondestructive measurement of fissile mass ( 235 U, 239 Pu..) by Active Neutron Interrogation (ANI), when dealing with matrices containing materials (Cl, H...) influencing the neutron flux. The idea is to use the neutron capture reaction (n,γ) to determine the matrix composition to adjust the ANI calibration coefficient value. This study, dealing with 118 litres, homogeneous drums of density less than 0,4 and composed of chlorinated and/or hydrogenated materials, leads to build abacus linking the γ ray peak areas to the ANI calibration coefficient. Validation assays of these abacus show a very good agreement between the corrected and true fissile masses for hydrogenated matrices (max. relative standard deviation: 23 %) and quite good for chlorinated and hydrogenated matrices (58 %). The developed correction method improves the measured values. It may be extended to 0,45 density, heterogeneous drums. (author)
Carena, M S; Herfurth, F; Ames, F; Audi, G; Beck, D; Blaum, K; Bollen, G; Kellerbauer, A G; Kluge, H J; Kuckein, M; Lunney, M D; Moore, R B; Oinonen, M; Rodríguez, D; Sauvan, E; Scheidenberger, C
2003-01-01
Precision electroweak data presently-favors a weakly-coupled Higgs sector as the mechanism responsible for electroweak symmetry breaking. Low-energy supersymmetry provides a natural framework for weakly-coupled elementary scalars. In this review, we summarize the theoretical properties of the Standard Model (SM) Higgs boson and the Higgs sector of the minimal super-symmetric extension of the Standard Model (MSSM). We then survey the phenomenology of the SM and MSSM Higgs bosons at the Tevatron, LHC and a future e**+e**- linear collider. We focus on the Higgs discovery potential of present and future colliders and stress the importance of precision measurements of Higgs boson properties. 459 Refs.31 The Penning trap mass spectrometer ISOLTRAP is a facility for high- precision mass measurements of short-lived radioactive nuclei installed at ISOLDE/CERN in Geneva. More than 200 masses have been measured with relative uncertainties of 1 multiplied by 10**-**7 or even close to 1 multiplied by 10**-**8 in special c...
On-line mass spectometry of nuclear reactions induced by heavy ions
International Nuclear Information System (INIS)
Saint Simon, M. de.
1977-01-01
The adaptation of the on-line mass-spectrometric technique to the special conditions of heavy ion induced reactions is described. The method is very selective about A and Z, even for the very heavy reaction products in counterpart of the limitation of its applications to the alkaline elements only. This method is used in order to study the effects of angular momentum brought by the projectile in the complete fusion process and in the following neutron evaporation. The analysis of excitation functions shows that the increase in mass of the projectile has not always the effect of increasing the rotation energy of the compound nucleus. The on-line mass spectrometry has allowed to study heavy ion induced fission. Measurements of complementary isotopic distributions of fission products make it possible to explain that the total number of neutrons emitted per fission can be always deduced from the fragment excitation energy. The study of the isotope distribution variance shows that the statistical model for fission is in good agreement with experimental results after taking into account the non-fusion processes [fr
Carter, Holly; Amlôt, Richard; Williams, Richard; Rubin, G. James; Drury, John
2016-01-01
This short report presents a response to an article written by Cibulsky et al. (2016). The paper by Cibulsky et al. presents a useful and timely overview of the evidence surrounding the technical and operational aspects of mass casualty decontamination. It identifies three priority targets for future research, the third of which is how casualties' needs can be met in ways that best support compliance with and effectiveness of casualty decontamination. While further investigation into behavioural, communication and privacy issues during mass decontamination is warranted, there is now a substantial body of research in this area which is not considered in detail in the succinct summary provided by Cibulsky et al. (2016). In this short report, we summarise the available evidence around likely public behaviour during mass decontamination, effective communication strategies, and potential issues resulting from a lack of privacy. Our intention is to help further focus the research needs in this area and highlight topics on which more research is needed. PMID:27790381
Low mass dielectrons radiated off cold nuclear matter measured with HADES
Directory of Open Access Journals (Sweden)
Lorenz M.
2014-03-01
Full Text Available The High Acceptance DiElectron Spectrometer HADES [1] is installed at the Helmholtzzentrum für Schwerionenforschung (GSI accelerator facility in Darmstadt. It investigates dielectron emission and strangeness production in the 1-3 AGeV regime. A recent experiment series focusses on medium-modifications of light vector mesons in cold nuclear matter. In two runs, p+p and p+Nb reactions were investigated at 3.5 GeV beam energy; about 9·109 events have been registered. In contrast to other experiments the high acceptance of the HADES allows for a detailed analysis of electron pairs with low momenta relative to nuclear matter, where modifications of the spectral functions of vector mesons are predicted to be most prominent. Comparing these low momentum electron pairs to the reference measurement in the elementary p+p reaction, we find in fact a strong modification of the spectral distribution in the whole vector meson region.
The congruence energy: A contribution to nuclear masses and deformation energies
International Nuclear Information System (INIS)
Myers, W.D.; Swiatecki, W.J.
1995-06-01
The difference between measured binding energies and those calculated using a shell- and pairing-corrected Thomas-Fermi model can be described approximately by C(I) = -10exp(-4.2|I|) MeV. The authors' interpretation of this extra binding is in terms of the granularity of quantal nucleonic density distributions, which leads to a stronger interaction for a neutron and proton with congruent nodal structures of their wave functions. The predicted doubling of this congruence energy in fission is supported by an analysis of measured fission barriers and by a study of wave functions in a dividing Hill-Wheeler box potential. A semi-empirical formula for the shape-dependent congruence energy is described
The congruence energy: a contribution to nuclear masses, deformation energies and fission barriers
International Nuclear Information System (INIS)
Myers, W.D.; Swiatecki, W.J.
1997-01-01
The difference between measured binding energies and those calculated using a shell- and pairing-corrected Thomas-Fermi model can be described approximately by C(I)=-10 exp(-4.2 vertical stroke I vertical stroke) MeV, where I=(N-Z)/A. Our interpretation of this extra binding is in terms of the granularity of quantal nucleonic density distributions, which leads to a stronger interaction for a neutron and proton with congruent nodal structures of their wave functions. The predicted doubling of this congruence energy in fission is supported by an analysis of measured fission barriers and by a study of wave functions in a dividing Hill-Wheeler box potential. A semi-empirical formula for the shape-dependent congruence energy is described. (orig.)
Nuclear physics: Macroscopic aspects
International Nuclear Information System (INIS)
Swiatecki, W.J.
1993-12-01
A systematic macroscopic, leptodermous approach to nuclear statics and dynamics is described, based formally on the assumptions ℎ → 0 and b/R << 1, where b is the surface diffuseness and R the nuclear radius. The resulting static model of shell-corrected nuclear binding energies and deformabilities is accurate to better than 1 part in a thousand and yields a firm determination of the principal properties of the nuclear fluid. As regards dynamics, the above approach suggests that nuclear shape evolutions will often be dominated by dissipation, but quantitative comparisons with experimental data are more difficult than in the case of statics. In its simplest liquid drop version the model exhibits interesting formal connections to the classic astronomical problem of rotating gravitating masses
International Nuclear Information System (INIS)
Travis, J.R.
1985-01-01
It is now possible to analyze the time-dependent, fully three-dimensional behavior of hydrogen diffusion flames in nuclear reactor containments. This analysis involves coupling the full Navier-Stokes equations with multi-species transport to the global chemical kinetics of hydrogen combustion. A transport equation for the subgrid scale turbulent kinetic energy density is solved to produce the time and space dependent turbulent transport coefficients. The heat transfer coefficient governing the exchange of heat between fluid computational cells adjacent to wall cells is calculated by a modified Reynolds analogy formulation. The analysis of a MARK-III containment indicates very complex flow patterns that greatly influence fluid and wall temperatures and heat fluxes. 18 refs., 24 figs
Squeeze-out of nuclear matter as a function of projectile energy and mass
International Nuclear Information System (INIS)
Gutbrod, H.H.; Kampert, K.H.; Kolb, B.; Poskanzer, A.M.; Ritter, H.G.; Schicker, R.; Schmidt, H.R.
1990-01-01
Squeeze-out, a component of the collective flow of nuclear matter, is the preferential emission of particles out of the reaction plane. Using the sphericity method the out-of-plane/in-plane ratio of the kinetic energy flow has been analyzed as a function of multiplicity and beam energy for Ca+Ca, Nb+Nb, and Au+Au collisions measured with the Plastic Ball detector at the Bevalac. Also, azimuthal distribution of the particles around the flow axis are presented together with the extracted out-of-plane/in-plane ratios. Finally, the rapidity dependence of the out-of-plane/in-plane ratio has been investigated with a new method using the transverse momentum components of the particles
Analysis of heat and mass transfer in sub-seabed disposal of nuclear waste
International Nuclear Information System (INIS)
Hickox, C.E.; Gartling, D.K.; McVey, D.F.; Russo, A.J.; Nuttall, H.E.
1980-01-01
A mathematical basis is developed for the prediction of thermal and radionuclide transport in marine sediments. The theory is applied to the study of radioactive waste disposal by emplacement, in specially designed containers, well below the sediment/water interface. Numerical results are obtained for a specified model problem through use of two computer programs designed primarily for the analysis of waste disposal problems. One program (MARIAH) provides descriptions of the temperature and velocity fields induced by the presence of a container of thermally active nuclear waste. A second program (IONMIG), which utilizes the results of the thermal analysis, is used to provide predictions for the migration of four representative radionuclides: 239 Pu, 137 Cs, 129 I, and 99 Tc
International Nuclear Information System (INIS)
Hermanns, H.J.
1977-04-01
By the example of light-water cooled nuclear reactors, the state of the calculation methods at disposal for calculating mass flow and steam quality distribution (sub-channel analysis) is indicated. Particular regard was paid to the transport phenomena occurring in reactor fuel elements in the range of two phase flow. Experimentally determined values were compared with recalculations of these experiments with the sub-channel code COBRA; from the results of these comparing calculations, conclusions could be drawn on the suitability of this code for defined applications. Limits of reliability could be determined to some extent. Based on the experience gained and the study of individual physical model concepts, recognized as being important, a sub-channel model was drawn up and the corresponding numerical computer code (SIEWAS) worked out. Experiments made at GE could be reproduced with the code SIEWAS with sufficient accuracy. (orig.) [de
International Nuclear Information System (INIS)
Malinowski, E.R.
1978-01-01
Based on the theory of error for abstract factor analysis described earlier, a theory of error for target factor analysis is developed. The theory shows how the error in the data matrix mixes with the error in the target test vector. The apparent error in a target test is found to be a vector sum of the real error in the target vector and the real error in the predicted vector. The theory predicts the magnitudes of these errors without requiring any a priori knowledge of the error in the data matrix or the target vector. A reliability function and a spoil function are developed for the purpose of assessing the validity and the worthiness of a target vector. Examples from model data, mass spectrometry and nuclear magnetic resonance spectrometry are presented. (Auth.)
International Nuclear Information System (INIS)
Anon.
1975-01-01
All methods described for subsampling and analysis of UF 6 are in routine use at United States Atomic Energy Commission installations. A gravimetric method is included for U and titrimetric methods, for Cl 2 and U. Mass spectrometric methods are given for both double and single standard procedures for U-isotopic content and for semiquantitative determination of hydrocarbons, chlorocarbons, and partially substituted halohydrocarbons. Spectroscopic methods are described for 232 U, fission products, Pu, and Np. In some instances an ion exchange- or extraction-separation is specified prior to the spectroscopic determination. Mass spectroscopic procedures for 31 trace elements are included, as are spectrophotometric methods for Br 2 , Si, P, Ti, V, W, Th, and Mo. Following a preliminary separation for some elements, emission spectroscopic procedures are described for B, Si, Ru, Hf, Mo, Nb, Ta, Ti, W, Zr, V, Th, rare earths, and other elements. Procedures for the determination of Sb, Ru, Al, Cd, Co, Ca, Cr, Fe, Pb, Mg, Mn, Ni, K, Na, and Zn by atomic absorption methods are included. The preparation of high-purity U 3 O 8 by the hydrolysis of UF 6 to UO 2 F 2 which upon drying and pyrohydrolysis yields U 3 O 8 is described
DEFF Research Database (Denmark)
Turcot, Valérie; Lu, Yingchang; Highland, Heather M
2018-01-01
In the published version of this paper, the name of author Emanuele Di Angelantonio was misspelled. This error has now been corrected in the HTML and PDF versions of the article.......In the published version of this paper, the name of author Emanuele Di Angelantonio was misspelled. This error has now been corrected in the HTML and PDF versions of the article....
DEFF Research Database (Denmark)
Grundle, D S; Löscher, C R; Krahmann, G
2018-01-01
A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.......A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper....
International Nuclear Information System (INIS)
SanLaholma, Juhani
1989-01-01
The ENS Information Committee carried out an assessment of public opinion and news media. The conclusions of this assessment are presented. The ENS recognized fully the significant role of the news media in reflecting public opinion in the nuclear field. It was concluded that it is worthwhile and important for the nuclear organizations to consider why unverified, even false, information appears so often in the media. The study emphasized that the nuclear organizations' relations with the news media are of high significance. ENS emphasized that it is important for the nuclear sector sector to pursue an active and frank information policy with the news media. ENS recognized that it is our task to prepare and provide the news media and the public with prompt, correct and objective information it is endless work but, at the same time, our only way of winning and attaining credibility and confidence among the public
International Nuclear Information System (INIS)
Gu Haiwei; Pan Zhengzheng; Xi Bowei; Asiago, Vincent; Musselman, Brian; Raftery, Daniel
2011-01-01
Nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) are the two most commonly used analytical tools in metabolomics, and their complementary nature makes the combination particularly attractive. A combined analytical approach can improve the potential for providing reliable methods to detect metabolic profile alterations in biofluids or tissues caused by disease, toxicity, etc. In this paper, 1 H NMR spectroscopy and direct analysis in real time (DART)-MS were used for the metabolomics analysis of serum samples from breast cancer patients and healthy controls. Principal component analysis (PCA) of the NMR data showed that the first principal component (PC1) scores could be used to separate cancer from normal samples. However, no such obvious clustering could be observed in the PCA score plot of DART-MS data, even though DART-MS can provide a rich and informative metabolic profile. Using a modified multivariate statistical approach, the DART-MS data were then reevaluated by orthogonal signal correction (OSC) pretreated partial least squares (PLS), in which the Y matrix in the regression was set to the PC1 score values from the NMR data analysis. This approach, and a similar one using the first latent variable from PLS-DA of the NMR data resulted in a significant improvement of the separation between the disease samples and normals, and a metabolic profile related to breast cancer could be extracted from DART-MS. The new approach allows the disease classification to be expressed on a continuum as opposed to a binary scale and thus better represents the disease and healthy classifications. An improved metabolic profile obtained by combining MS and NMR by this approach may be useful to achieve more accurate disease detection and gain more insight regarding disease mechanisms and biology.
Gu, Haiwei; Pan, Zhengzheng; Xi, Bowei; Asiago, Vincent; Musselman, Brian; Raftery, Daniel
2011-02-07
Nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) are the two most commonly used analytical tools in metabolomics, and their complementary nature makes the combination particularly attractive. A combined analytical approach can improve the potential for providing reliable methods to detect metabolic profile alterations in biofluids or tissues caused by disease, toxicity, etc. In this paper, (1)H NMR spectroscopy and direct analysis in real time (DART)-MS were used for the metabolomics analysis of serum samples from breast cancer patients and healthy controls. Principal component analysis (PCA) of the NMR data showed that the first principal component (PC1) scores could be used to separate cancer from normal samples. However, no such obvious clustering could be observed in the PCA score plot of DART-MS data, even though DART-MS can provide a rich and informative metabolic profile. Using a modified multivariate statistical approach, the DART-MS data were then reevaluated by orthogonal signal correction (OSC) pretreated partial least squares (PLS), in which the Y matrix in the regression was set to the PC1 score values from the NMR data analysis. This approach, and a similar one using the first latent variable from PLS-DA of the NMR data resulted in a significant improvement of the separation between the disease samples and normals, and a metabolic profile related to breast cancer could be extracted from DART-MS. The new approach allows the disease classification to be expressed on a continuum as opposed to a binary scale and thus better represents the disease and healthy classifications. An improved metabolic profile obtained by combining MS and NMR by this approach may be useful to achieve more accurate disease detection and gain more insight regarding disease mechanisms and biology. Copyright © 2010 Elsevier B.V. All rights reserved.
Hydrogeological evidence of low rock mass permeabilities in ordovician strata: Bruce nuclear site
International Nuclear Information System (INIS)
Beauheim, R.L.; Roberts, R.M.; Avis, J.D.; Heagle, D.
2011-01-01
One of the key attributes contributing to the suitability of the Bruce nuclear site to host a Deep Geologic Repository (DGR) for Low and Intermediate Level Waste (L&ILW) is the low permeability of the Ordovician host rock and of the overlying and underlying strata. The permeability of these rocks is so low that diffusion is a much more significant transport mechanism than advection. Hydrogeological evidence for the low permeability of the Ordovician strata comes from two principal sources, direct and indirect. Direct evidence of low permeability is provided by the hydraulic testing performed in deep boreholes, DGR-2 through DGR-6. Straddle-packer hydraulic testing was performed in 57 Ordovician intervals in these five holes. The testing provided continuous coverage using ~30-m straddle intervals of the Ordovician strata exposed in boreholes DGR-2, DGR-3, DGR-4, and DGR-5, while testing was targeted on discontinuous 10.2-m intervals in DGR-6. The average horizontal hydraulic conductivities of these intervals determined from the tests ranged from 2E-16 to 2E-10 m/s. The Lower Member of the Cobourg Formation, which is the proposed host formation for the DGR, was found to have a horizontal hydraulic conductivity of 4E-15 to 3E-14 m/s. The only horizontal hydraulic conductivity values measured that were greater than 2E-12 m/s are from the Black River Group, located at the base of the Ordovician sedimentary sequence. Indirect evidence of low permeability is provided by the observed distribution of hydraulic heads through the Ordovician sequence. Hydraulic head profiles, defined by hydraulic testing and confirmed by Westbay multilevel monitoring systems, show significant underpressures relative to a density-compensated hydrostatic condition throughout most of the Ordovician strata above the Black River Group, whereas the Black River Group is overpressured. Pressure differences of 1 MPa or more are observed between adjacent intervals in the boreholes. The observed
Baryon interactions from lattice QCD with physical quark masses - Nuclear forces and ΞΞ forces -
Doi, Takumi; Iritani, Takumi; Aoki, Sinya; Gongyo, Shinya; Hatsuda, Tetsuo; Ikeda, Yoichi; Inoue, Takashi; Ishii, Noriyoshi; Miyamoto, Takaya; Nemura, Hidekatsu; Sasaki, Kenji
2018-03-01
We present the latest lattice QCD results for baryon interactions obtained at nearly physical quark masses. Nf = 2 + 1 nonperturbatively O(a)-improved Wilson quark action with stout smearing and Iwasaki gauge action are employed on the lattice of (96a)4 ≃(8.1fm)4 with a-1 ≃2.3 GeV, where mπ ≃146 MeV and mK ≃525 MeV. In this report, we study the two-nucleon systems and two-Ξ systems in 1S0 channel and 3S1-3D1 coupled channel, and extract central and tensor interactions by the HAL QCD method. We also present the results for the NΩ interaction in 5S2 channel which is relevant to the NΩ pair-momentum correlation in heavy-ion collision experiments.
Fission product nuclear data obtained by use of an on-line mass spectrometer
International Nuclear Information System (INIS)
Reeder, P.L.; Wright, J.F.; Anderl, R.A.
1975-01-01
A Spectrometer for On-Line Analysis of Radionuclides (SOLAR) has been installed at a 1 MW TRIGA reactor at Washington State University. Fission product ions from a combination target/ion source located within the thermal column are brought out to a 60 0 magnetic sector mass spectrometer. Surface ionization provides copious beams of Rb + and Cs + ions and less intense beams of Br - and I - ions with negligible contamination by other elements. About 40 fission product nuclides can thus be chemically and physically separated in times of less than 1 second. Past results on independent and cumulative fission yields along with measurements of half-lives of some very neutron-rich nuclides are presented. Current work on delayed-neutron emission probabilities and energy spectra of delayed neutrons from individual nuclides is described. (7 tables, 2 figures) (U.S.)
International Nuclear Information System (INIS)
2014-01-01
This document proposes a presentation and discussion of the main notions, issues, principles, or characteristics related to nuclear energy: radioactivity (presence in the environment, explanation, measurement, periods and activities, low doses, applications), fuel cycle (front end, mining and ore concentration, refining and conversion, fuel fabrication, in the reactor, back end with reprocessing and recycling, transport), the future of the thorium-based fuel cycle (motivations, benefits and drawbacks), nuclear reactors (principles of fission reactors, reactor types, PWR reactors, BWR, heavy-water reactor, high temperature reactor of HTR, future reactors), nuclear wastes (classification, packaging and storage, legal aspects, vitrification, choice of a deep storage option, quantities and costs, foreign practices), radioactive releases of nuclear installations (main released radio-elements, radioactive releases by nuclear reactors and by La Hague plant, gaseous and liquid effluents, impact of releases, regulation), the OSPAR Convention, management and safety of nuclear activities (from control to quality insurance, to quality management and to sustainable development), national safety bodies (mission, means, organisation and activities of ASN, IRSN, HCTISN), international bodies, nuclear and medicine (applications of radioactivity, medical imagery, radiotherapy, doses in nuclear medicine, implementation, the accident in Epinal), nuclear and R and D (past R and D programmes and expenses, main actors in France and present funding, main R and D axis, international cooperation)
Ross, Charles W; Simonsick, William J; Bogusky, Michael J; Celikay, Recep W; Guare, James P; Newton, Randall C
2016-06-28
Ceramides are a central unit of all sphingolipids which have been identified as sites of biological recognition on cellular membranes mediating cell growth and differentiation. Several glycosphingolipids have been isolated, displaying immunomodulatory and anti-tumor activities. These molecules have generated considerable interest as potential vaccine adjuvants in humans. Accurate analyses of these and related sphingosine analogues are important for the characterization of structure, biological function, and metabolism. We report the complementary use of direct laser desorption ionization (DLDI), sheath flow electrospray ionization (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) and high-field nuclear magnetic resonance (NMR) analysis for the rapid, accurate identification of hexacosanoylceramide and starting materials. DLDI does not require stringent sample preparation and yields representative ions. Sheath-flow ESI yields ions of the product and byproducts and was significantly better than monospray ESI due to improved compound solubility. Negative ion sheath flow ESI provided data of starting materials and products all in one acquisition as hexacosanoic acid does not ionize efficiently when ceramides are present. NMR provided characterization of these lipid molecules complementing the results obtained from MS analyses. NMR data was able to differentiate straight chain versus branched chain alkyl groups not easily obtained from mass spectrometry.
Directory of Open Access Journals (Sweden)
Charles W. Ross
2016-06-01
Full Text Available Ceramides are a central unit of all sphingolipids which have been identified as sites of biological recognition on cellular membranes mediating cell growth and differentiation. Several glycosphingolipids have been isolated, displaying immunomodulatory and anti-tumor activities. These molecules have generated considerable interest as potential vaccine adjuvants in humans. Accurate analyses of these and related sphingosine analogues are important for the characterization of structure, biological function, and metabolism. We report the complementary use of direct laser desorption ionization (DLDI, sheath flow electrospray ionization (ESI Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS and high-field nuclear magnetic resonance (NMR analysis for the rapid, accurate identification of hexacosanoylceramide and starting materials. DLDI does not require stringent sample preparation and yields representative ions. Sheath-flow ESI yields ions of the product and byproducts and was significantly better than monospray ESI due to improved compound solubility. Negative ion sheath flow ESI provided data of starting materials and products all in one acquisition as hexacosanoic acid does not ionize efficiently when ceramides are present. NMR provided characterization of these lipid molecules complementing the results obtained from MS analyses. NMR data was able to differentiate straight chain versus branched chain alkyl groups not easily obtained from mass spectrometry.
International Nuclear Information System (INIS)
Nottoli, Emmanuelle; Bienvenu, Philippe; Labet, Alexandre; Bourlès, Didier; Arnold, Maurice; Bertaux, Maité
2014-01-01
Determining long-lived radionuclide concentrations in radioactive waste has fundamental implications for the long-term management of storage sites. This paper focuses on the measurement of low 129 I contents in ion exchange resins used for primary fluid purification in Pressurised Water Reactors (PWR). Iodine-129 concentrations were successfully determined using Accelerator Mass Spectrometry (AMS) following a chemical procedure which included (1) acid digestion of resin samples in HNO 3 /HClO 4 , (2) radioactive decontamination by selective iodine extraction using a new chromatographic resin (CL Resin), and (3) AgI precipitation. Measured 129 I concentrations ranged from 4 to 12 ng/g, i.e. from 0.03 to 0.08 Bq/g. The calculation of 129 I/ 137 Cs activity ratios used for routine waste management produced values in agreement with the few available data for PWR resin samples. - Highlights: • In the context of radioactive waste management, this study aimed at measuring 129 I in spent resins using accelerator mass spectrometry. • The treatment procedure included microwave acid digestion of samples, iodine extraction by CL resins and AgI precipitation. • Developed first on synthetic matrices, the chemical treatment procedure was then successfully applied to real resin samples. • 129 I concentrations ranged from 4 to 12 ng/g of dry resin. • Results are in agreement with previous measurements and support reference values currently used for nuclear resin management
International Nuclear Information System (INIS)
GRASHER, A.A.
2001-01-01
The purpose of this report is to provide a discussion of the accountable inventory of Hanford Site nuclear material (NM) over the operating period. This report does not provide judgments on impacts to the Hanford Site environs by the reported waste streams or inventory. The focus of this report is on the processes, facilities, and process streams that constituted the flow primarily of plutonium and uranium through the Hanford Site. The material balance reports (MBRS) are the basis of the NM accountable inventory maintained by each of the various contractors used by the U.S. Department of Energy (DOE) and its predecessors to operate the Hanford Site. The inventory was tracked in terms of a starting inventory, receipts, transfers, and ending inventory. The various components of the inventory are discussed as well as the uncertainty in the measurement values used to establish plant inventory and material transfers. The accountable NM inventory does not report all the NM on the Hanford Site and this difference is discussed relative to some representative nuclides. The composition and location of the current accountable inventory are provided, as well as the latest approved set (2000) of flow diagrams of the proposed disposition of the excess accountable NM inventory listed on the Idaho National Engineering and Environmental Laboratory (INEEL) web page
International Nuclear Information System (INIS)
Nottoli, Emmanuelle; Bienvenu, Philippe; Labet, Alexandre; Bertaux, Maite; Bourles, Didier; Arnold, Maurice
2013-01-01
Radiological characterization of nuclear waste is essential for storage sites management. However, most of Long-Lived Radionuclides (LLRN), important for long-term management, are difficult to measure since concentration levels are very low and waste matrices generally complex. In an industrial approach, LLRN concentrations are not directly measured in waste samples but assessed from scaling factors with respect to easily measured gamma emitters. Ideally, the key nuclide chosen ( 60 Co, 137 Cs) should be produced by a similar mechanism (fission or activation) as the LLRN of interest and should have similar physicochemical properties. However, the uncertainty on the scaling factors, determined from experimental and/or calculation data, can be quite important. Consequently, studies are performed to develop analytical procedures which would lead to determine precisely the concentration of LLRN in nuclear waste. In this context, the aim of this study was to determine the concentrations of three LLRN: 129 I (T 1/2 = 15.7*10 6 a), 41 Ca (T 1/2 = 9.94*10 4 a) and 10 Be (T 1/2 = 1.387*10 6 a) in spent resins used for primary fluid purification in Pressurized Water Reactors using Accelerator Mass Spectrometry (AMS) for measurement. The AMS technique combined mass spectrometry and nuclear physics to achieve highly efficient molecular and elemental isobars separation. Energies of several Million Electron-Volt transferred to the ions in the first accelerating part of specifically developed tandem accelerators lead to molecular isobars destruction through interaction with the argon gas used to strip the injected negative ions to positive ones. At the exit of the tandem accelerator, the energy acquired in both accelerating parts allows an elemental isobars separation based on their significantly different energy loss (dE) while passing through a thickness of matter dx that is proportional to their atomic number (Z) and inversely proportional to ions velocity (v) according to the
International Nuclear Information System (INIS)
Avrigeanu, M.
1982-01-01
A detailed analysis is presented, based on Hauser-Feshbach statistical model calculations of the γ-ray excitation functions measured in the sup(74,76)Ge ( 12 C, xn) and sup(72,73)Ge ( 16 O,xnyp) reactions. The most usual quantities provided by the in beam γ-ray measurements such as the cross sections for the population of the final states as well as the decay scheme and the degree of alignment of these states mainly offer the means of testing models of both the reaction mechanism and nuclear properties of high excitation energies, since they concentrate information on the whole reaction process. Experimental information on sup(85,86)Sr and sup(85,86)Y, γ-decay scheme and the excitation functions for the population of the final states were obtained by sub(74,76)Ge ( 12 C,αn), n = 2-4, sup(74,76)Ge ( 14 N,xn) n = 3-5, sup(72,73)Ge ( 16 O,xnyp), x = 1-3, y=1 reactions at incident energies between 35 and 60 MW. Statistical model calculations in the Hauser-Feshbach formalism have been compared with the experimental γ-ray excitation functions. The competitive emission of neutrons, protons, alpha particles and gamma rays from the compound nucleus has been considered in the calculations. The calculations describe satisfactorily the total cross sections for the population of the 2n, 3n and 4n channels for 12 C + sup(74,76)Ge and 2n, np, 3n and 2np channels for 16 O + 72 Ge. The calculations are sensitive to the characteristics of the excited levels (such as spin values) but htis this sensitivity could be exploited with some reliability only if one makes use of a rather complete level scheme in the calculations. In the case of 2n, np, 3n and 2 np channels for 16 O+ 73 Ge one concludes on the reliability of consideration some structural aspects in the calculations
Nuclear analysis of the Chornobyl fuel containing masses with heterogeneous fuel distribution
International Nuclear Information System (INIS)
Turski, R. B.
1998-01-01
Although significant data has been obtained on the condition and composition of the fuel containing masses (FCM) located in the concrete chambers under the Chernobyl Unit 4 reactor cavity, there is still uncertainty regarding the possible recriticality of this material. The high radiation levels make access extremely difficult, and most of the samples are from the FCM surface regions. There is little information on the interior regions of the FCM, and one cannot assume with confidence that the surface measurements are representative of the interior regions. Therefore, reasonable assumptions on the key parameters such as fuel concentration, the concentrations of impurities and neutron poisons (especially boron), the void fraction of the FCM due to its known porosity, and the degrees of fuel heterogeneity, are necessary to evaluate the possibility of recriticality. The void fraction is important since it introduces the possibility of water moderator being distributed throughout the FCM. Calculations indicate that the addition of 10 to 30 volume percent (v/o) water to the FCM has a significant impact on the calculated reactivity of the FCM. Therefore, water addition must be considered carefully. The other possible moderators are graphite and silicone dioxide. As discussed later in this paper, silicone dioxide moderation does not represent a criticality threat. For graphite, both heterogeneous fuel arrangements and very large volume fractions of graphite are necessary for a graphite moderated system to go critical. Based on the observations and measurements of the FCM compositions, these conditions do not appear creditable for the Chernobyl FCM. Therefore, the focus of the analysis reported in this paper will be on reasonable heterogeneous fuel arrangements and water moderation. The analysis will evaluate a range of fuel and diluent compositions
Moco, S.I.A.; Forshed, J.; Vos, de C.H.; Bino, R.J.; Vervoort, J.J.M.
2008-01-01
Nuclear magnetic resonance (NMR) and liquid chromatography-mass spectrometry (LCMS) are frequently used as technological platforms for metabolomics applications. In this study, the metabolic profiles of ripe fruits from 50 different tomato cultivars, including beef, cherry and round types, were
International Nuclear Information System (INIS)
Cheng Lan; Huang Weizhi; Zhou Baosen
1996-01-01
Using the matrix elements of M-3Y force as the equivalent G-matrix elements, the spectra of 210 Pb, 206 Pb, 206 Hg and 210 Po are calculated in the framework of the Folded Diagram Method. The results show that such equivalent matrix elements are suitable for microscopic calculations of the nuclear structure in heavy mass region
du Bois de Maquillé, Laurence; Renaudin, Laetitia; Goutelard, Florence; Jardy, Alain; Vial, Jérôme; Thiébaut, Didier
2013-02-08
EDTA is a chelating agent that has been used in decontamination processes. Its quantification is required for nuclear waste management because it affects the mobility of radionuclides and metals in environment and, thus, can harm the safety of the storage. Ion-pair chromatography coupled with electrospray mass spectrometry detection is a convenient method for quantitative analysis of EDTA but EDTA should be present as a single anionic chelate form. However, radioactive liquid wastes contain high concentrations of heavy metals and salts and consequently, EDTA is present as several chelates. Speciation studies were carried out to choose a metal cation to be added in excess to the solution to obtain a major chelate form. Fe is the predominant cation and Fe(III)-EDTA is thermodynamically favored but these speciation studies showed that ferric hydroxide precipitated above pH 2. Consequently, it was not possible to quantify EDTA as Fe(III)-EDTA complex. Therefore, Ni(2+) was chosen but its use implied pretreatment with a base of the solution to eliminate Fe. Deuterated EDTA was used as tracer in order to validate the whole procedure, from the treatment with a base to the final analysis by HPLC-ESI-MS. This analytical method was successfully applied for EDTA quantification in two real effluents resulting from a nuclear liquid waste process. A recovery rate between 60 and 80% was obtained. The limit of detection of this method was determined at 34×10(-9)mol L(-1). Copyright © 2012 Elsevier B.V. All rights reserved.
Turcot, Valérie; Lu, Yingchang; Highland, Heather M; Schurmann, Claudia; Justice, Anne E; Fine, Rebecca S; Bradfield, Jonathan P; Esko, Tõnu; Giri, Ayush; Graff, Mariaelisa; Guo, Xiuqing; Hendricks, Audrey E; Karaderi, Tugce; Lempradl, Adelheid; Locke, Adam E; Mahajan, Anubha; Marouli, Eirini; Sivapalaratnam, Suthesh; Young, Kristin L; Alfred, Tamuno; Feitosa, Mary F; Masca, Nicholas G D; Manning, Alisa K; Medina-Gomez, Carolina; Mudgal, Poorva; Ng, Maggie C Y; Reiner, Alex P; Vedantam, Sailaja; Willems, Sara M; Winkler, Thomas W; Abecasis, Gonçalo; Aben, Katja K; Alam, Dewan S; Alharthi, Sameer E; Allison, Matthew; Amouyel, Philippe; Asselbergs, Folkert W; Auer, Paul L; Balkau, Beverley; Bang, Lia E; Barroso, Inês; Bastarache, Lisa; Benn, Marianne; Bergmann, Sven; Bielak, Lawrence F; Blüher, Matthias; Boehnke, Michael; Boeing, Heiner; Boerwinkle, Eric; Böger, Carsten A; Bork-Jensen, Jette; Bots, Michiel L; Bottinger, Erwin P; Bowden, Donald W; Brandslund, Ivan; Breen, Gerome; Brilliant, Murray H; Broer, Linda; Brumat, Marco; Burt, Amber A; Butterworth, Adam S; Campbell, Peter T; Cappellani, Stefania; Carey, David J; Catamo, Eulalia; Caulfield, Mark J; Chambers, John C; Chasman, Daniel I; Chen, Yii-Der I; Chowdhury, Rajiv; Christensen, Cramer; Chu, Audrey Y; Cocca, Massimiliano; Collins, Francis S; Cook, James P; Corley, Janie; Corominas Galbany, Jordi; Cox, Amanda J; Crosslin, David S; Cuellar-Partida, Gabriel; D'Eustacchio, Angela; Danesh, John; Davies, Gail; Bakker, Paul I W; Groot, Mark C H; Mutsert, Renée; Deary, Ian J; Dedoussis, George; Demerath, Ellen W; Heijer, Martin; Hollander, Anneke I; Ruijter, Hester M; Dennis, Joe G; Denny, Josh C; Di Angelantonio, Emanuele; Drenos, Fotios; Du, Mengmeng; Dubé, Marie-Pierre; Dunning, Alison M; Easton, Douglas F; Edwards, Todd L; Ellinghaus, David; Ellinor, Patrick T; Elliott, Paul; Evangelou, Evangelos; Farmaki, Aliki-Eleni; Farooqi, I Sadaf; Faul, Jessica D; Fauser, Sascha; Feng, Shuang; Ferrannini, Ele; Ferrieres, Jean; Florez, Jose C; Ford, Ian; Fornage, Myriam; Franco, Oscar H; Franke, Andre; Franks, Paul W; Friedrich, Nele; Frikke-Schmidt, Ruth; Galesloot, Tessel E; Gan, Wei; Gandin, Ilaria; Gasparini, Paolo; Gibson, Jane; Giedraitis, Vilmantas; Gjesing, Anette P; Gordon-Larsen, Penny; Gorski, Mathias; Grabe, Hans-Jörgen; Grant, Struan F A; Grarup, Niels; Griffiths, Helen L; Grove, Megan L; Gudnason, Vilmundur; Gustafsson, Stefan; Haessler, Jeff; Hakonarson, Hakon; Hammerschlag, Anke R; Hansen, Torben; Harris, Kathleen Mullan; Harris, Tamara B; Hattersley, Andrew T; Have, Christian T; Hayward, Caroline; He, Liang; Heard-Costa, Nancy L; Heath, Andrew C; Heid, Iris M; Helgeland, Øyvind; Hernesniemi, Jussi; Hewitt, Alex W; Holmen, Oddgeir L; Hovingh, G Kees; Howson, Joanna M M; Hu, Yao; Huang, Paul L; Huffman, Jennifer E; Ikram, M Arfan; Ingelsson, Erik; Jackson, Anne U; Jansson, Jan-Håkan; Jarvik, Gail P; Jensen, Gorm B; Jia, Yucheng; Johansson, Stefan; Jørgensen, Marit E; Jørgensen, Torben; Jukema, J Wouter; Kahali, Bratati; Kahn, René S; Kähönen, Mika; Kamstrup, Pia R; Kanoni, Stavroula; Kaprio, Jaakko; Karaleftheri, Maria; Kardia, Sharon L R; Karpe, Fredrik; Kathiresan, Sekar; Kee, Frank; Kiemeney, Lambertus A; Kim, Eric; Kitajima, Hidetoshi; Komulainen, Pirjo; Kooner, Jaspal S; Kooperberg, Charles; Korhonen, Tellervo; Kovacs, Peter; Kuivaniemi, Helena; Kutalik, Zoltán; Kuulasmaa, Kari; Kuusisto, Johanna; Laakso, Markku; Lakka, Timo A; Lamparter, David; Lange, Ethan M; Lange, Leslie A; Langenberg, Claudia; Larson, Eric B; Lee, Nanette R; Lehtimäki, Terho; Lewis, Cora E; Li, Huaixing; Li, Jin; Li-Gao, Ruifang; Lin, Honghuang; Lin, Keng-Hung; Lin, Li-An; Lin, Xu; Lind, Lars; Lindström, Jaana; Linneberg, Allan; Liu, Ching-Ti; Liu, Dajiang J; Liu, Yongmei; Lo, Ken S; Lophatananon, Artitaya; Lotery, Andrew J; Loukola, Anu; Luan, Jian'an; Lubitz, Steven A; Lyytikäinen, Leo-Pekka; Männistö, Satu; Marenne, Gaëlle; Mazul, Angela L; McCarthy, Mark I; McKean-Cowdin, Roberta; Medland, Sarah E; Meidtner, Karina; Milani, Lili; Mistry, Vanisha; Mitchell, Paul; Mohlke, Karen L; Moilanen, Leena; Moitry, Marie; Montgomery, Grant W; Mook-Kanamori, Dennis O; Moore, Carmel; Mori, Trevor A; Morris, Andrew D; Morris, Andrew P; Müller-Nurasyid, Martina; Munroe, Patricia B; Nalls, Mike A; Narisu, Narisu; Nelson, Christopher P; Neville, Matt; Nielsen, Sune F; Nikus, Kjell; Njølstad, Pål R; Nordestgaard, Børge G; Nyholt, Dale R; O'Connel, Jeffrey R; O'Donoghue, Michelle L; Olde Loohuis, Loes M; Ophoff, Roel A; Owen, Katharine R; Packard, Chris J; Padmanabhan, Sandosh; Palmer, Colin N A; Palmer, Nicholette D; Pasterkamp, Gerard; Patel, Aniruddh P; Pattie, Alison; Pedersen, Oluf; Peissig, Peggy L; Peloso, Gina M; Pennell, Craig E; Perola, Markus; Perry, James A; Perry, John R B; Pers, Tune H; Person, Thomas N; Peters, Annette; Petersen, Eva R B; Peyser, Patricia A; Pirie, Ailith; Polasek, Ozren; Polderman, Tinca J; Puolijoki, Hannu; Raitakari, Olli T; Rasheed, Asif; Rauramaa, Rainer; Reilly, Dermot F; Renström, Frida; Rheinberger, Myriam; Ridker, Paul M; Rioux, John D; Rivas, Manuel A; Roberts, David J; Robertson, Neil R; Robino, Antonietta; Rolandsson, Olov; Rudan, Igor; Ruth, Katherine S; Saleheen, Danish; Salomaa, Veikko; Samani, Nilesh J; Sapkota, Yadav; Sattar, Naveed; Schoen, Robert E; Schreiner, Pamela J; Schulze, Matthias B; Scott, Robert A; Segura-Lepe, Marcelo P; Shah, Svati H; Sheu, Wayne H-H; Sim, Xueling; Slater, Andrew J; Small, Kerrin S; Smith, Albert V; Southam, Lorraine; Spector, Timothy D; Speliotes, Elizabeth K; Starr, John M; Stefansson, Kari; Steinthorsdottir, Valgerdur; Stirrups, Kathleen E; Strauch, Konstantin; Stringham, Heather M; Stumvoll, Michael; Sun, Liang; Surendran, Praveen; Swift, Amy J; Tada, Hayato; Tansey, Katherine E; Tardif, Jean-Claude; Taylor, Kent D; Teumer, Alexander; Thompson, Deborah J; Thorleifsson, Gudmar; Thorsteinsdottir, Unnur; Thuesen, Betina H; Tönjes, Anke; Tromp, Gerard; Trompet, Stella; Tsafantakis, Emmanouil; Tuomilehto, Jaakko; Tybjaerg-Hansen, Anne; Tyrer, Jonathan P; Uher, Rudolf; Uitterlinden, André G; Uusitupa, Matti; Laan, Sander W; Duijn, Cornelia M; Leeuwen, Nienke; van Setten, Jessica; Vanhala, Mauno; Varbo, Anette; Varga, Tibor V; Varma, Rohit; Velez Edwards, Digna R; Vermeulen, Sita H; Veronesi, Giovanni; Vestergaard, Henrik; Vitart, Veronique; Vogt, Thomas F; Völker, Uwe; Vuckovic, Dragana; Wagenknecht, Lynne E; Walker, Mark; Wallentin, Lars; Wang, Feijie; Wang, Carol A; Wang, Shuai; Wang, Yiqin; Ware, Erin B; Wareham, Nicholas J; Warren, Helen R; Waterworth, Dawn M; Wessel, Jennifer; White, Harvey D; Willer, Cristen J; Wilson, James G; Witte, Daniel R; Wood, Andrew R; Wu, Ying; Yaghootkar, Hanieh; Yao, Jie; Yao, Pang; Yerges-Armstrong, Laura M; Young, Robin; Zeggini, Eleftheria; Zhan, Xiaowei; Zhang, Weihua; Zhao, Jing Hua; Zhao, Wei; Zhao, Wei; Zhou, Wei; Zondervan, Krina T; Rotter, Jerome I; Pospisilik, John A; Rivadeneira, Fernando; Borecki, Ingrid B; Deloukas, Panos; Frayling, Timothy M; Lettre, Guillaume; North, Kari E; Lindgren, Cecilia M; Hirschhorn, Joel N; Loos, Ruth J F
2018-05-01
In the version of this article originally published, one of the two authors with the name Wei Zhao was omitted from the author list and the affiliations for both authors were assigned to the single Wei Zhao in the author list. In addition, the ORCID for Wei Zhao (Department of Biostatistics and Epidemiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA) was incorrectly assigned to author Wei Zhou. The errors have been corrected in the HTML and PDF versions of the article.
Querejeta, Miguel; Meidt, Sharon E.; Schinnerer, Eva; Cisternas, Mauricio; Muñoz-Mateos, Juan Carlos; Sheth, Kartik; Knapen, Johan; van de Ven, Glenn; Norris, Mark A.; Peletier, Reynier; Laurikainen, Eija; Salo, Heikki; Holwerda, Benne W.; Athanassoula, E.; Bosma, Albert; Groves, Brent; Ho, Luis C.; Gadotti, Dimitri A.; Zaritsky, Dennis; Regan, Michael; Hinz, Joannah; Gil de Paz, Armando; Menendez-Delmestre, Karin; Seibert, Mark; Mizusawa, Trisha; Kim, Taehyun; Erroz-Ferrer, Santiago; Laine, Jarkko; Comerón, Sébastien
2015-07-01
The mid-infrared is an optimal window to trace stellar mass in nearby galaxies and the 3.6 μ {{m}} IRAC band has been exploited to this effect, but such mass estimates can be biased by dust emission. We present our pipeline to reveal the old stellar flux at 3.6 μm and obtain stellar mass maps for more than 1600 galaxies available from the Spitzer Survey of Stellar Structure in Galaxies (S4G). This survey consists of images in two infrared bands (3.6 and 4.5 μ {{m}}), and we use the Independent Component Analysis (ICA) method presented in Meidt et al. to separate the dominant light from old stars and the dust emission that can significantly contribute to the observed 3.6 μ {{m}} flux. We exclude from our ICA analysis galaxies with low signal-to-noise ratio ({{S}}/{{N}}\\lt 10) and those with original [3.6]-[4.5] colors compatible with an old stellar population, indicative of little dust emission (mostly early Hubble types, which can directly provide good mass maps). For the remaining 1251 galaxies to which ICA was successfully applied, we find that as much as 10%-30% of the total light at 3.6 μ {{m}} typically originates from dust, and locally it can reach even higher values. This contamination fraction shows a correlation with specific star formation rates, confirming that the dust emission that we detect is related to star formation. Additionally, we have used our large sample of mass estimates to calibrate a relationship of effective mass-to-light ratio (M/L) as a function of observed [3.6]-[4.5] color: {log}({\\text{}}M/L) = -0.339(+/- 0.057) × ([3.6]-[4.5])-0.336(+/- 0.002). Our final pipeline products have been made public through IRSA, providing the astronomical community with an unprecedentedly large set of stellar mass maps ready to use for scientific applications.
International Nuclear Information System (INIS)
Pereira de Oliveira, O. Jr.; Sarkis, J.E.S.; Ponzevera, E.; Alonso, A.; De Bolle, W.; Quetel, C.
2008-01-01
The n(U 235 )/n(U 238 ) isotope amount ratio in a set of samples was measured using two modern analytical techniques: quadrupole inductively coupled plasma mass spectrometry (ICP-QMS) and multi-collector magnetic sector inductively coupled plasma mass spectrometry (MC-ICPMS). The measured ratios were compared to the certified ratios provided by the high accuracy gas source mass spectrometry (GSMS). The components of the uncertainty were identified and their contribution to the combined standard uncertainty was estimated using the recommendations of the ISO-GUM guide. The values of the measurement uncertainty and bias were determined and then compared to the International Target Values for Measurement Uncertainties in Safeguarding Nuclear Materials. It appears that only the measurements performed by MC-ICPMS can meet the stringent requirements of international nuclear safeguards. (authors)
Energy Technology Data Exchange (ETDEWEB)
Nadykto, B.A. [RFNC-VNIIEF, Nizhni Novgorod Region (Russian Federation)
2001-07-01
The nuclear weapons production has resulted in accumulation of a large quantity of plutonium and uranium highly enriched with uranium-235 isotope (many tons). The work under ISTC Project 332B-97 treated the issues of safe plutonium storage through making critical-mass-free plutonium oxide compositions with neutron poisons. This completely excludes immediate utilization (without chemical reprocessing) of retained plutonium in nuclear devices. It is therewith possible to locate plutonium most compactly in the storage facility, which would allow reduction in required storage areas and costs. The issues of the surplus weapon-grade plutonium management and utilization have been comprehensively studied in the recent decade. The issues are treated in multiple scientific publications, conferences, and seminars. At the same time, issues of nuclear power engineering actinide waste storage are studied no less extensively. The general issues are material radioactivity and energy release and nuclear accident hazards due to critical mass generation. Plutonium accumulated in nuclear power plant spent fuel is more accessible than weapon-grade plutonium and can become of higher and higher interest with time as its activity reduces, including as material for nuclear devices. The urgency of plutonium management is presently related not only to accumulation of surplus weapon-grade plutonium, but also to the fact that it is high time to decide what has to be done regarding reactor plutonium. Presently, the possibility of actinide separation from NPP spent nuclear fuel and compact underground burial separately from other (mainly fragment) activity is being considered. Actinide and neutron poison base critical-mass-free ceramic materials (similar to plutonium ceramics) may be useful for this burial method. (author)
International Nuclear Information System (INIS)
Nadykto, B.A.
2001-01-01
The nuclear weapons production has resulted in accumulation of a large quantity of plutonium and uranium highly enriched with uranium-235 isotope (many tons). The work under ISTC Project 332B-97 treated the issues of safe plutonium storage through making critical-mass-free plutonium oxide compositions with neutron poisons. This completely excludes immediate utilization (without chemical reprocessing) of retained plutonium in nuclear devices. It is therewith possible to locate plutonium most compactly in the storage facility, which would allow reduction in required storage areas and costs. The issues of the surplus weapon-grade plutonium management and utilization have been comprehensively studied in the recent decade. The issues are treated in multiple scientific publications, conferences, and seminars. At the same time, issues of nuclear power engineering actinide waste storage are studied no less extensively. The general issues are material radioactivity and energy release and nuclear accident hazards due to critical mass generation. Plutonium accumulated in nuclear power plant spent fuel is more accessible than weapon-grade plutonium and can become of higher and higher interest with time as its activity reduces, including as material for nuclear devices. The urgency of plutonium management is presently related not only to accumulation of surplus weapon-grade plutonium, but also to the fact that it is high time to decide what has to be done regarding reactor plutonium. Presently, the possibility of actinide separation from NPP spent nuclear fuel and compact underground burial separately from other (mainly fragment) activity is being considered. Actinide and neutron poison base critical-mass-free ceramic materials (similar to plutonium ceramics) may be useful for this burial method. (author)
Energy Technology Data Exchange (ETDEWEB)
Tudela, X.; Garcia-Vila, J. H.; Jornet, J. [Hospital General de Castello. Castello de la Plana (Spain)
2001-07-01
Stromal tumors of the gastrointestinal tract encompass a group of neoplasms representing 1% to 3% of all digestive system tumors. When located in the stomach, their tendency to exhibit and exophytic growth pattern makes it necessary to establish the differential diagnosis with respect to other gastric tumors (lymphoma, exophytic adenocarcinoma) and nongastrointestinal masses. We present a case that illustrated the difficulties associated with the imaging diagnosis of these lesions and the importance of modern radiological techniques (helical computed tomography and magnetic resonance) and the correct interpretation on the part of radiologists to orient pathologists and clinicians toward the diagnosis and proper treatment. (Author) 10 refs.
International Nuclear Information System (INIS)
Ozdemir, A.; Sevnic, C.; Selamaet, U.; Kamaci, B.; Atalay, S.
2007-01-01
No prospective studies have evaluated the effects of correction of iron deficiency anemia on insulin resistance in non-diabetic premenopausal women with iron deficiency anemia. All patients were treated with oral iron preparations. Insulin resistance was calculated with the Homeostasis Model Assessment formula. All patients were dichotomized by the median for age and BMI to assess how the relationship between iron deficiency anemia and insulin resistance was affected by the age and BMI. Although the fasting glucose levels did not change meaningfully, statistically significant decreases were found in fasting insulin levels following anemia treatment both in the younger age ( = 40 years) and the high BMI (>-27Kg/m) subgroups. Post-treatment fasting insulin levels were positively correlated both with BMI (r=0.386, P=0.004) and post-treatment hemoglobin levels. (r=0.285, P=0.036). Regression analysis revealed that the factors affecting post-treatment insulin levels were BMI (P=0.001) and post-treatment hemoglobin levels (p=0.030). Our results show that following he correction of iron deficiency anemia, insulin levels and HOMA scores decrease in younger and lean non-diabetic premenopausal women. (author)
American Society for Testing and Materials. Philadelphia
2010-01-01
1.1 This test method covers the determination of 67 elements in uranium dioxide samples and nuclear grade uranium compounds and solutions without matrix separation by inductively coupled plasma mass spectrometry (ICP-MS). The elements are listed in Table 1. These elements can also be determined in uranyl nitrate hexahydrate (UNH), uranium hexafluoride (UF6), triuranium octoxide (U3O8) and uranium trioxide (UO3) if these compounds are treated and converted to the same uranium concentration solution. 1.2 The elements boron, sodium, silicon, phosphorus, potassium, calcium and iron can be determined using different techniques. The analyst's instrumentation will determine which procedure is chosen for the analysis. 1.3 The test method for technetium-99 is given in Annex A1. 1.4 The values stated in SI units are to be regarded as standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish ...
International Nuclear Information System (INIS)
McVey, D.F.; Erickson, K.L.; Seyfried, W.E. Jr.
1983-01-01
In this chapter the authors discuss the current status of heat and mass transport studies in the marine red clay sediments that are being considered as a nuclear waste isolation medium and review analytical and experimental studies. Calculations based on numerical models indicate that for a maximum allowable sediment-canister interface temperatures of 200 0 to 250 0 C, the sediment can absorb about 1.5kW initial power from waste buried 30 m in the sediment in a canister that is 3 m long and 0.3 m in diameter. The resulting fluid displacement due to convections is found to be small, less than 1 m. Laboratory studies of the geochemical effects induced by heating sediment-seawater mixtures indicate that the canister and waste form should be designed to resist a hot, relatively acidic oxidizing environment. Since the thermally altered sediment volume of about 5.5 m/sup 3/ is small relative to the sediment volume overlying the canister, the acid and oxidizing conditions should significantly affect the properties of the far field only if thermodiffusional process (Soret effect) prove to be significant. If thermodiffusional effects are important, however, near-field chemistry will differ considerably from that predicted from results of constant temperature sediment-seawater interaction experiments
Manea, V.; Ascher, P.; Atanasov, D.; Barzakh, A. E.; Beck, D.; Blaum, K.; Borgmann, Ch.; Breitenfeldt, M.; Cakirli, R. B.; Cocolios, T. E.; Day Goodacre, T.; Fedorov, D. V.; Fedosseev, V. N.; George, S.; Herfurth, F.; Kowalska, M.; Kreim, S.; Litvinov, Yu. A.; Lunney, D.; Marsh, B.; Neidherr, D.; Rosenbusch, M.; Rossel, R. E.; Rothe, S.; Schweikhard, L.; Wienholtz, F.; Wolf, R. N.; Zuber, K.
2017-05-01
We present a study of nuclear shape coexistence in the region of neutron-deficient lead isotopes. The midshell gold isotopes 180,185,188,190Au (Z =79 ), the two long-lived nuclear states in 197At (Z =85 ), and the neutron-rich nuclide 219At were produced by the ISOLDE facility at CERN and their masses were determined with the high-precision Penning-trap mass spectrometer ISOLTRAP. The studied gold isotopes address the trend of binding energies in a region of the nuclear chart where the nuclear charge radii show pronounced discontinuities. Significant deviations from the atomic-mass evaluation were found for Au,190188. The new trend of two-neutron separation energies is smoother, although it does reveal the onset of deformation. The origin of this effect is interpreted in connection to the odd-even staggering of binding energies, as well as theoretically by Hartree-Fock-Bogoliubov calculations including quasiparticle blocking. The role of blocking for reproducing the large odd-even staggering of charge radii in the mercury isotopic chain is illustrated.
Energy Technology Data Exchange (ETDEWEB)
Loche, F
2006-10-15
In the framework of radioactive waste drums control, difficulties arise in the nondestructive measurement of fissile mass ({sup 235}U, {sup 239}Pu..) by Active Neutron Interrogation (ANI), when dealing with matrices containing materials (Cl, H...) influencing the neutron flux. The idea is to use the neutron capture reaction (n,{gamma}) to determine the matrix composition to adjust the ANI calibration coefficient value. This study, dealing with 118 litres, homogeneous drums of density less than 0,4 and composed of chlorinated and/or hydrogenated materials, leads to build abacus linking the {gamma} ray peak areas to the ANI calibration coefficient. Validation assays of these abacus show a very good agreement between the corrected and true fissile masses for hydrogenated matrices (max. relative standard deviation: 23 %) and quite good for chlorinated and hydrogenated matrices (58 %). The developed correction method improves the measured values. It may be extended to 0,45 density, heterogeneous drums. (author)
DEFF Research Database (Denmark)
Stokholm, Jakob; Blaser, Martin J.; Thorsen, Jonathan
2018-01-01
The originally published version of this Article contained an incorrect version of Figure 3 that was introduced following peer review and inadvertently not corrected during the production process. Both versions contain the same set of abundance data, but the incorrect version has the children...
DEFF Research Database (Denmark)
Flachsbart, Friederike; Dose, Janina; Gentschew, Liljana
2018-01-01
The original version of this Article contained an error in the spelling of the author Robert Häsler, which was incorrectly given as Robert Häesler. This has now been corrected in both the PDF and HTML versions of the Article....
DEFF Research Database (Denmark)
Roehle, Robert; Wieske, Viktoria; Schuetz, Georg M
2018-01-01
The original version of this article, published on 19 March 2018, unfortunately contained a mistake. The following correction has therefore been made in the original: The names of the authors Philipp A. Kaufmann, Ronny Ralf Buechel and Bernhard A. Herzog were presented incorrectly....
Activities report in nuclear physics
Jansen, J. F. W.; Scholten, O.
1987-01-01
Experimental studies of giant resonances, nuclear structure, light mass systems, and heavy mass systems are summarized. Theoretical studies of nuclear structure, and dynamics are described. Electroweak interactions; atomic and surface physics; applied nuclear physics; and nuclear medicine are
International Nuclear Information System (INIS)
Poinssot, Ch.; Ecole Normale Superieure, 92 - Fontenay-aux-Roses
1998-01-01
The initial stage of a high level nuclear waste disposal will be characterised by a large heat release within the near-field environment of the canisters. This heat flux caused by radioactive decay will lead to an increase of temperature and a subsequent thermal gradient between the 'hot' canisters and the 'cold'geological medium. In addition, this thermal gradient will decrease with time due to the heat decay although it could last hundred years. What will be the consequences of such a thermal field varying both on space and time for the alteration of the different constituents of the near field environment. In particular, what could be the effects on the radionuclides migration in the accidental case of an early breach of a canister during the thermal stage? This study brings significant answers to these questions in the light of a performance assessment study. This work is supported by a triple methodological approach involving experimental studies, modelling calculations and a natural analogues study. This complete work demonstrates that a thermal gradient leads to a large re-distribution of elements within the system: some elements are incorporated in the solid phases of the hot end (Si, Zr, Ca) whereas some others are in those of the cold end (Fe, Al, Zn). The confrontation of the results of very simple experiments with the results of a model built on equilibrium thermodynamics allow us to evidence the probable mechanisms causing this mass transport: out-of-equilibrium thermodiffusion processes coupled to irreversible precipitation. Moreover, the effects of the variation of temperatures with time is studied by the way of a natural system which underwent a similar temperature evolution as a disposal and which was initially rich in uranium: the Jurassic Alpine bauxites. In addition, part of the initial bauxite escaped this temperature transformations due to their incorporation in outer thrusting nappes. They are used as a reference. (author)
Full Text Available ... out more. Corrective Jaw Surgery Corrective Jaw Surgery Orthognathic surgery is performed to correct the misalignment of jaws ... out more. Corrective Jaw Surgery Corrective Jaw Surgery Orthognathic surgery is performed to correct the misalignment of jaws ...
International Nuclear Information System (INIS)
Anon.
2000-01-01
The first text deals with a new circular concerning the collect of the medicine radioactive wastes, containing radium. This campaign wants to incite people to let go their radioactive wastes (needles, tubes) in order to suppress any danger. The second text presents a decree of the 31 december 1999, relative to the limitations of noise and external risks resulting from the nuclear facilities exploitation: noise, atmospheric pollution, water pollution, wastes management and fire prevention. (A.L.B.)
The Romanian nuclear regulatory body as a nuclear communicator
International Nuclear Information System (INIS)
Cluculescu, Cristina
2000-01-01
A comprehensive nuclear law environment could be a relevant tool to promote greater confidence in the nuclear energy. Romania has had laws in place governing the regulation of nuclear activities since 1974, which remained in force throughout and subsequent to the national constitutional changes. Up to December 1996, the CNCAN activities were based on Law No. 61/1974 for the development of the nuclear activities in Romania and Law No. 61982 on the quality assurance of the nuclear facilities and nuclear power plants. The Nuclear Safety legislation has been enacted in November 1974 (Law No. 61/1974) and it followed as closely as possible (for that time) the US Atomic Energy Act of 1954, as amended subsequently. The Romanian nuclear regulatory body, called National Commission for Nuclear Activities Control (CNCAN) is a governmental organization responsible for the development of the regulatory framework, the control of its implementation and for the licensing of nuclear facilities. An important issue of CNCAN is to provide the correct and reasoning information to the public. The most important topics focused on nuclear activities for the interest of mass media in Romania are: Radioactive waste management; The cost and benefit of nuclear energy compared by conventional energy; The conditions for transportation of radioactive materials; The consequences of a suppositional nuclear accidents; The safety in operation for nuclear installations. The information provided to press and public by regulatory body is clearly and well structured. The target is to clearly explain to mass media and the public should understand very well the difference between the meaning of a nuclear accident, nuclear incident or nuclear event. CNCAN monitories and surveys the operation in safe conditions the nuclear facilities and plants, the protection against nuclear radiation of the professionally exposed personnel, of the population, of the environment and the material goods. It is also
Maldonado, Alejandro F; Aucar, Gustavo A; Melo, Juan I
2014-09-01
The nuclear magnetic shieldings of Si, Ge, and Sn in MH(4-n) Y(n) (M = Si, Ge, Sn; Y = F, Cl, Br, I and n = 1-4) molecular systems are highly influenced by the substitution of one or more hydrogens by heavy-halogen atoms. We applied the linear response elimination of small components (LRESC) formalism to calculate those shieldings and learn whether including only a few of the leading relativistic correction terms is sufficient to be able to quantitatively reproduce the full relativistic value. It was observed that the nuclear magnetic shieldings change as the number of heavy halogen substituents and their weights vary, and the pattern of σ(M) generally does not exhibit the normal halogen dependence (NHD) behavior that can be seen in similar molecular systems containing carbon atoms. We also analyzed each relativistic correction afforded by the LRESC method and split them in two: core-dependent and ligand-dependent contributions; we then looked for the electronic mechanisms involved in the different relativistic effects and in the total relativistic value. Based on this analysis, we were able to study the electronic mechanism involved in a recently proposed relativistic effect, the "heavy atom effect on vicinal heavy atom" (HAVHA), in more detail. We found that the main electronic mechanism is the spin-orbit or σ p (T(3)) correction, although other corrections such as σ p (S(1)) and σ p (S(3)) are also important. Finally, we analyzed proton magnetic shieldings and found that, for molecules containing Sn as the central atom, σ(H) decreases as the number of heavy halogen substituents (of the same type: either F, Cl, or Br) increases, albeit at different rates for different halogens. σ(H) only increase as the number of halogen substituents increases if the halogen is iodine.
Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Banerjee, A.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Bouchet, J.; Brandin, A. V.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Caines, H.; Calder'on de la Barca S'anchez, M.; Campbell, J. M.; Cebra, D.; Cervantes, M. C.; Chakaberia, I.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, J. H.; Chen, X.; Cheng, J.; Cherney, M.; Christie, W.; Codrington, M. J. M.; Contin, G.; Crawford, H. J.; Das, S.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; di Ruzza, B.; Didenko, L.; Dilks, C.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Eppley, G.; Esha, R.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Federic, P.; Fedorisin, J.; Feng; Filip, P.; Fisyak, Y.; Flores, C. E.; Fulek, L.; Gagliardi, C. A.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, S.; Gupta, A.; Guryn, W.; Hamad, A.; Hamed, A.; Haque, R.; Harris, J. W.; He, L.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, H. Z.; Huang, X.; Huang, B.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jang, H.; Jiang, K.; Judd, E. G.; Kabana, S.; Kalinkin, D.; Kang, K.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Khan, Z. H.; Kikola, D. P.; Kisel, I.; Kisiel, A.; Klein, S. R.; Koetke, D. D.; Kollegger, T.; Kosarzewski, L. K.; Kotchenda, L.; Kraishan, A. F.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Kycia, R. A.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Li, X.; Li, X.; Li, W.; Li, Z. M.; Li, Y.; Li, C.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, L.; Ma, R.; Ma, G. L.; Ma, Y. G.; Magdy, N.; Majka, R.; Manion, A.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; Meehan, K.; Minaev, N. G.; Mioduszewski, S.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Okorokov, V.; Olvitt, D. L.; Page, B. S.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Peterson, A.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Poniatowska, K.; Porter, J.; Posik, M.; Poskanzer, A. M.; Pruthi, N. K.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandacz, A.; Sandweiss, J.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, W. B.; Schmitz, N.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shanmuganathan, P. V.; Shao, M.; Sharma, M. K.; Sharma, B.; Shen, W. Q.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Sikora, R.; Simko, M.; Skoby, M. J.; Smirnov, N.; Smirnov, D.; Solanki, D.; Song, L.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Summa, B. J.; Sun, Y.; Sun, Z.; Sun, X. M.; Sun, X.; Surrow, B.; Svirida, D. N.; Szelezniak, M. A.; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarnowsky, T.; Tawfik, A. N.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Tripathy, S. K.; Trzeciak, B. A.; Tsai, O. D.; Ullrich, T.; Underwood, D. G.; Upsal, I.; Van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Varma, R.; Vasiliev, A. N.; Vertesi, R.; Videbaek, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wang, Y.; Wang, F.; Wang, H.; Wang, J. S.; Wang, G.; Wang, Y.; Webb, J. C.; Webb, G.; Wen, L.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, Z.; Xu, Q. H.; Xu, N.; Xu, H.; Xu, Y. F.; Yang, Y.; Yang, C.; Yang, S.; Yang, Q.; Yang, Y.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I.-K.; Yu, N.; Zbroszczyk, H.; Zha, W.; Zhang, J. B.; Zhang, X. P.; Zhang, S.; Zhang, J.; Zhang, Z.; Zhang, Y.; Zhang, J. L.; Zhao, F.; Zhao, J.; Zhong, C.; Zhou, L.; Zhu, X.; Zoulkarneeva, Y.; Zyzak, M.
2015-11-01
The acceptance-corrected dielectron excess mass spectra, where the known hadronic sources have been subtracted from the inclusive dielectron mass spectra, are reported for the first time at mid-rapidity |yee | < 1 in minimum-bias Au +Au collisions at √{sNN} = 19.6 and 200 GeV. The excess mass spectra are consistently described by a model calculation with a broadened ρ spectral function for Mee < 1.1 GeV /c2. The integrated dielectron excess yield at √{sNN} = 19.6 GeV for 0.4
Directory of Open Access Journals (Sweden)
L. Adamczyk
2015-11-01
Full Text Available The acceptance-corrected dielectron excess mass spectra, where the known hadronic sources have been subtracted from the inclusive dielectron mass spectra, are reported for the first time at mid-rapidity |yee|<1 in minimum-bias Au+Au collisions at sNN=19.6 and 200 GeV. The excess mass spectra are consistently described by a model calculation with a broadened ρ spectral function for Mee<1.1 GeV/c2. The integrated dielectron excess yield at sNN=19.6 GeV for 0.4
Geological Corrections in Gravimetry
Mikuška, J.; Marušiak, I.
2015-12-01
Applying corrections for the known geology to gravity data can be traced back into the first quarter of the 20th century. Later on, mostly in areas with sedimentary cover, at local and regional scales, the correction known as gravity stripping has been in use since the mid 1960s, provided that there was enough geological information. Stripping at regional to global scales became possible after releasing the CRUST 2.0 and later CRUST 1.0 models in the years 2000 and 2013, respectively. Especially the later model provides quite a new view on the relevant geometries and on the topographic and crustal densities as well as on the crust/mantle density contrast. Thus, the isostatic corrections, which have been often used in the past, can now be replaced by procedures working with an independent information interpreted primarily from seismic studies. We have developed software for performing geological corrections in space domain, based on a-priori geometry and density grids which can be of either rectangular or spherical/ellipsoidal types with cells of the shapes of rectangles, tesseroids or triangles. It enables us to calculate the required gravitational effects not only in the form of surface maps or profiles but, for instance, also along vertical lines, which can shed some additional light on the nature of the geological correction. The software can work at a variety of scales and considers the input information to an optional distance from the calculation point up to the antipodes. Our main objective is to treat geological correction as an alternative to accounting for the topography with varying densities since the bottoms of the topographic masses, namely the geoid or ellipsoid, generally do not represent geological boundaries. As well we would like to call attention to the possible distortions of the corrected gravity anomalies. This work was supported by the Slovak Research and Development Agency under the contract APVV-0827-12.
Nuclear Effects on Heavy Boson Production at RHIC and LHC
Zhang, X; Zhang, Xiaofei; Fai, George
2002-01-01
We predict W and Z transverse momentum distributions from proton-proton and nuclear collisions at RHIC and LHC. A resummation formalism with power corrections to the renormalization group equations is used. The dependence of the resummed QCD results on the non-perturbative input is very weak for the systems considered. Shadowing effects are discussed and found to be unimportant at RHIC, but important for LHC. We study the enhancement of power corrections due to multiple scattering in nuclear collisions and numerically illustrate the weak effects of the dependence on the nuclear mass.
Atomic mass prediction from the mass formula with empirical shell terms
International Nuclear Information System (INIS)
Uno, Masahiro; Yamada, Masami
1982-08-01
The mass-excess prediction of about 8000 nuclides was calculated from two types of the atomic mass formulas with empirical shell terms of Uno and Yamada. The theoretical errors to accompany the calculated mass excess are also presented. These errors have been obtained by a new statistical method. The mass-excess prediction includes the term of the gross feature of a nuclear mass surface, the shell terms and a small correction term for odd-odd nuclei. Two functional forms for the shell terms were used. The first is the constant form, and the sencond is the linear form. In determining the values of shell parameters, only the data of even-even and odd-A nuclei were used. A new statistical method was applied, in which the error inherent to the mass formula was taken account. The obtained shell parameters and the values of mass excess are shown in tables. (Kato, T.)
DEFF Research Database (Denmark)
Faber, Rasmus; Buczek, Aneta; Kupka, Teobald
2017-01-01
), coupled cluster singles and doubles (CCSD), coupled cluster singles and doubles with perturbative triples corrections (CCSD(T)) and Kohn-Sham density functional theory (DFT) with the B3LYP exchange-correlation functional methods in combination with the second order vibrational perturbation theory (VPT2...
Development of the Heated Length Correction Factor
International Nuclear Information System (INIS)
Park, Ho-Young; Kim, Kang-Hoon; Nahm, Kee-Yil; Jung, Yil-Sup; Park, Eung-Jun
2008-01-01
The Critical Heat Flux (CHF) on a nuclear fuel is defined by the function of flow channel geometry and flow condition. According to the selection of the explanatory variable, there are three hypotheses to explain CHF at uniformly heated vertical rod (inlet condition hypothesis, exit condition hypothesis, local condition hypothesis). For inlet condition hypothesis, CHF is characterized by function of system pressure, rod diameter, rod length, mass flow and inlet subcooling. For exit condition hypothesis, exit quality substitutes for inlet subcooling. Generally the heated length effect on CHF in exit condition hypothesis is smaller than that of other variables. Heated length is usually excluded in local condition hypothesis to describe the CHF with only local fluid conditions. Most of commercial plants currently use the empirical CHF correlation based on local condition hypothesis. Empirical CHF correlation is developed by the method of fitting the selected sensitive local variables to CHF test data using the multiple non-linear regression. Because this kind of method can not explain physical meaning, it is difficult to reflect the proper effect of complex geometry. So the recent CHF correlation development strategy of nuclear fuel vendor is making the basic CHF correlation which consists of basic flow variables (local fluid conditions) at first, and then the geometrical correction factors are compensated additionally. Because the functional forms of correction factors are determined from the independent test data which represent the corresponding geometry separately, it can be applied to other CHF correlation directly only with minor coefficient modification
International Nuclear Information System (INIS)
Yukhnovs'kij, Yi.R.; Kobrin, O.Je.; Tokarchuk, M.V.; Tokarevs'kij, V.V.
1997-01-01
The main forms of the existence of nuclear fuel and major concomitant factors of nuclear and ecological danger of the object 'Shelter' are presented. The processes of interaction between water and fuel containing materials have been analysed on the basis of experimental data
Directory of Open Access Journals (Sweden)
Hojae Lee
2016-04-01
Full Text Available Severe accident scenarios in nuclear reactors, such as nuclear meltdown, reveal that an extremely hot molten core may fall into the nuclear reactor cavity and seriously affect the safety of the nuclear containment vessel due to the chain reaction caused by the reaction between the molten core and concrete. This paper reports on research focused on the type and amount of vapor produced during the reaction between a high-temperature molten core and concrete, as well as on the erosion rate of concrete and the heat transfer characteristics at its vicinity. This study identifies the mass fraction and melting temperature as the most influential properties of concrete necessary for a safety analysis conducted in relation to the thermal interaction between the molten core and the basemat concrete. The types of concrete that are actually used in nuclear reactor cavities were investigated. The H2O content in concrete required for the computation of the relative amount of gases generated by the chemical reaction of the vapor, the quantity of CO2 necessary for computing the cooling speed of the molten core, and the melting temperature of concrete are evaluated experimentally for the molten core–concrete interaction analysis.