Science.gov

Sample records for nuclear properties

  1. Transport Properties in Nuclear Pasta

    NASA Astrophysics Data System (ADS)

    Caplan, Matthew; Horowitz, Charles; Berry, Donald; da Silva Schneider, Andre

    2016-09-01

    At the base of the inner crust of neutron stars, where matter is near the nuclear saturation density, nuclear matter arranges itself into exotic shapes such as cylinders and slabs, called `nuclear pasta.' Lepton scattering from these structures may govern the transport properties of the inner crust; electron scattering from protons in the pasta determines the thermal and electrical conductivity, as well as the shear viscosity of the inner crust. These properties may vary in pasta structures which form at various densities, temperatures, and proton fractions. In this talk, we report on our calculations of lepton transport in nuclear pasta and the implication for neutron star observables.

  2. Properties of the nuclear medium.

    PubMed

    Baldo, M; Burgio, G F

    2012-02-01

    We review our knowledge on the properties of the nuclear medium that have been studied, over many years, on the basis of many-body theory, laboratory experiments and astrophysical observations. Throughout the presentation particular emphasis is placed on the possible relationship and links between the nuclear medium and the structure of nuclei, including the limitations of such an approach. First we consider the realm of phenomenological laboratory data and astrophysical observations and the hints they can give on the characteristics that the nuclear medium should possess. The analysis is based on phenomenological models, that however have a strong basis on physical intuition and an impressive success. More microscopic models are also considered, and it is shown that they are able to give invaluable information on the nuclear medium, in particular on its equation of state. The interplay between laboratory experiments and astrophysical observations is particularly stressed, and it is shown how their complementarity enormously enriches our insights into the structure of the nuclear medium. We then introduce the nucleon-nucleon interaction and the microscopic many-body theory of nuclear matter, with a critical discussion about the different approaches and their results. The Landau-Fermi liquid theory is introduced and briefly discussed, and it is shown how fruitful it can be in discussing the macroscopic and low-energy properties of the nuclear medium. As an illustrative example, we discuss neutron matter at very low density, and it is shown how it can be treated within the many-body theory. The general bulk properties of the nuclear medium are reviewed to indicate at which stage of our knowledge we stand, taking into account the most recent developments both in theory and experiments. A section is dedicated to the pairing problem. The connection with nuclear structure is then discussed, on the basis of the energy density functional method. The possibility of linking

  3. Nuclear properties of mendelevium

    SciTech Connect

    Hoffman, D.C.

    1980-01-01

    The heavy Fm isotopes (/sup 258/Fm and /sup 259/Fm) so far appear to be unique in exhibiting very symmetric mass distributions and anomolously high fragment total kinetic energies. This effect appears to be associated with the Z = 100 proton configuration of the fissioning nuclide which can fission symmetrically into two fragments having the Z = 50 closed-proton shell configuration; /sup 256/Cf which has the same number of neutrons but only 98 protons does not exhibit these fission properties. Furthermore, /sup 259/Md, also having 158 neutrons but with 101 protons, fissions symmetrically but with a normal total kinetic energy. However, the total kinetic-energy distribution is extremely broad, indicating a range of fragment shapes at scission from spherical to highly distorted. It is extremely important to check more nuclides with Z greater than 100 and N greater than or equal to 158 to check the relative importance of the fragement proton and neutron shells. New methods are needed for measurements of half lives of ms or less and for providing positive identification of the Z and A of the fissioning species. Recent experiments indicate that /sup 259/Fm is produced with a 10 to 15 nb cross section in bombardments of /sup 248/Cm with /sup 18/O and that therefore extreme caution must be exercised in making assignments. However, transfer or deep inelastic reactions of this kind would appear to offer a good possibility for making the heavier isotopes of Md or Lr for study by bombarding Bk or Es targets with /sup 18/O.

  4. Nuclear properties for astrophysical applications

    SciTech Connect

    Moeller, P.; Nix, J.R.; Kratz, K.L.

    1994-09-23

    We tabulate the ground-state odd-proton and odd-neutron spins, proton and neutron pairing gaps, binding energies, neuton separation energies, quantities related to {beta}-delayed one, two and three neutron emission probabilities, {beta}-decay Q values and half-lives with respect to Gamow-Teller decay, proton separation energies, and {alpha}-decay Q values and half-lives. The starting point of the calculations is a calculation of nuclear ground-states and (information based on the finite-range droplet model and the folded-Yukawa single-particle model published in a previous issue of ATOMIC DATA AND NUCLEAR DATA TABLES. The {beta}-delayed neutron-emission probabilities and Gamow-Teller {beta}-decay rates are obtained from a QRPA model that uses single-particle levels and wave-functions at the calculated nuclear ground-state shape as the starting point.

  5. Nuclear property insurance: status and outlook

    SciTech Connect

    Long, J.D.

    1982-05-01

    This study was undertaken by the author in his capacity as a consultant to the United States Nuclear Regulatory Commission. His specific assignment was to ascertain the nature of the market for nuclear property insurance as purchased by utilities, identify the distinguishing characteristics of each type of insurance, verify the amount of insurance of each type available per nuclear site, speculate about the likely changes in such availability, define the major problems that contribute to the inadequacy of the insurance, and recommend the remedial action that NRC should take.

  6. The NUBASE2016 evaluation of nuclear properties

    NASA Astrophysics Data System (ADS)

    Audi, G.; Kondev, F. G.; Wang, Meng; Huang, W. J.; Naimi, S.

    2017-03-01

    This paper presents the NUBASE2016 evaluation that contains the recommended values for nuclear and decay properties of 3437 nuclides in their ground and excited isomeric (T1/2 >= 100 ns) states. All nuclides for which any experimental information is known were considered. NUBASE2016 covers all data published by October 2016 in primary (journal articles) and secondary (mainly laboratory reports and conference proceedings) references, together with the corresponding bibliographical information. During the development of NUBASE2016, the data available in the 'Evaluated Nuclear Structure Data File' (ENSDF) database were consulted and critically assessed for their validity and completeness. Furthermore, a large amount of new data and some older experimental results that were missing from ENSDF were compiled, evaluated and included in NUBASE2016. The atomic mass values were taken from the 'Atomic Mass Evaluation' (AME2016, second and third parts of the present issue). In cases where no experimental data were available for a particular nuclide, trends in the behavior of specific properties in neighboring nuclides (TNN) were examined. This approach allowed to estimate values for a range of properties that are labeled in NUBASE2016 as 'non-experimental' (flagged '#'). Evaluation procedures and policies used during the development of this database are presented, together with a detailed table of recommended values and their uncertainties. AMDC: http://amdc.impcas.ac.cn/ Contents The NUBASE2016 evaluation of nuclear propertiesAcrobat PDF (1.1 MB) Table I. The NUBASE2016 table of nuclear and decay propertiesAcrobat PDF (706 KB)

  7. Thorium dioxide: properties and nuclear applications

    SciTech Connect

    Belle, J.; Berman, R.M.

    1984-01-01

    This is the sixth book on reactor materials published under sponsorship of the Naval Reactors Office of the United States Department of Energy, formerly the United States Atomic Energy Commission. This book presents a comprehensive compilation of the most significant properties of thorium dioxide, much like the book Uranium Dioxide: Properties and Nuclear Applications presented information on the fuel material used in the Shippingport Pressurized Water Reactor core.

  8. NUBASE2012 Evaluation of Nuclear Properties

    SciTech Connect

    Wang, M.; Audi, G.; Pfeiffer, B.; Blachot, J.; Sun, X.

    2014-06-15

    NUBASE is a database containing the recommended values for the main properties of all known nuclides in their ground and excited isomeric states. Since the publication of the first version in 1997, NUBASE has been widely used in the nuclear science community. The latest version (NUBASE2012) was published in December 2012. Two specific examples are given to illustrate the evaluation policy of NUBASE2012.

  9. The NUBASE2016 evaluation of nuclear properties *

    SciTech Connect

    Audi, G.; Kondev, F. G.; Wang, Meng; Huang, W. J.; Naimi, S.

    2017-01-01

    This paper presents the NUBASE2016 evaluation that contains the recommended values for nuclear and decay properties of 3437 nuclides in their ground and excited isomeric (T1/2≥100 ns) states. All nuclides for which any experimental information is known were considered. NUBASE2016 covers all data published by October 2016 in primary (journal articles) and secondary (mainly laboratory reports and conference proceedings) references, together with the corresponding bibliographical information. During the development of NUBASE2016, the data available in the “Evaluated Nuclear Structure Data File” (ENSDF) database were consulted and critically assessed for their validity and completeness. Furthermore, a large amount of new data and some older experimental results that were missing from ENSDF were compiled, evaluated and included in NUBASE2016. The atomic mass values were taken from the “Atomic Mass Evaluation” (AME2016, second and third parts of the present issue). In cases where no experimental data were available for a particular nuclide, trends in the behavior of specific properties in neighboring nuclides (TNN) were examined. This approach allowed to estimate values for a range of properties that are labeled in NUBASE2016 as “non-experimental” (flagged “#”). Evaluation procedures and policies used during the development of this database are presented, together with a detailed table of recommended values and their uncertainties. AMDC: http://amdc.impcas.ac.cn/

  10. Hot magnetized nuclear matter: Thermodynamic and saturation properties

    NASA Astrophysics Data System (ADS)

    Rezaei, Z.; Bordbar, G. H.

    2017-03-01

    We have used a realistic nuclear potential, AV_{18}, and a many-body technique, the lowest-order constraint variational (LOCV) approach, to calculate the properties of hot magnetized nuclear matter. By investigating the free energy, spin polarization parameter, and symmetry energy, we have studied the temperature and magnetic field dependence of the saturation properties of magnetized nuclear matter. In addition, we have calculated the equation of state of magnetized nuclear matter at different temperatures and magnetic fields. It was found that the flashing temperature of nuclear matter decreases by increasing the magnetic field. In addition, we have studied the effect of the magnetic field on liquid gas phase transition of nuclear matter. The liquid gas coexistence curves, the order parameter of the liquid gas phase transition, and the properties of critical point at different magnetic fields have been calculated.

  11. D Meson Properties in Nuclear Medium from QCD Sum Rules

    NASA Astrophysics Data System (ADS)

    Suzuki, Kei; Gubler, Philipp; Oka, Makoto

    Properties of the pseudoscalar D meson in the nuclear medium are discussed from the point of view of QCD sum rules. QCD sum rules can relate condensates in the QCD vacuum to the properties of hadrons, so that in-medium modifications of hadron spectra naively correspond to condensate modifications through nuclear matter effects. We found that the reduction of the chiral-symmetry-breaking condensates including < \\bar{q}q> leads to increasing masses of both D+ and D- mesons at finite density. Furthermore, charge-symmetry-breaking condensates cause D+-D- (particle and anti-particle) mass splitting in the nuclear medium.

  12. Medium modifications of baryon properties in nuclear matter and hypernuclei

    NASA Astrophysics Data System (ADS)

    Liang, J. S.; Shen, H.

    2013-09-01

    We study the medium modifications of baryon properties in nuclear many-body systems, especially in Λ hypernuclei. The nucleon and the Λ hyperon are described in the Friedberg-Lee model as nontopological solitons which interact through the self-consistent exchange of scalar and vector mesons. The quark degrees of freedom are explicitly considered in the model, so that the medium effects on baryons could be investigated. It is found that the model can provide reasonable descriptions for nuclear matter, finite nuclei, and Λ hypernuclei. The present model predicts a significant increase of the baryon radius in nuclear medium.

  13. Mechanical Properties of Nuclear Fuel Surrogates using Picosecond Laser Ultrasonics

    SciTech Connect

    David Hurley; Marat Khafizov; Farhad Farzbod; Eric Burgett

    2013-05-01

    Detailed understanding between microstructure evolution and mechanical properties is important for designing new high burnup nuclear fuels. In this presentation we discuss the use of picosecond ultrasonics to measure localize changes in mechanical properties of fuel surrogates. We develop measurement techniques that can be applied to investigate heterogeneous elastic properties caused by localize changes in chemistry, grain microstructure caused by recrystallization, and mechanical properties of small samples prepared using focused ion beam sample preparation. Emphasis is placed on understanding the relationship between microstructure and mechanical properties

  14. Atomic, Crystal, Elastic, Thermal, Nuclear, and Other Properties of Beryllium

    SciTech Connect

    Goldberg, A

    2006-02-01

    This report is part of a series of documents that provide a background to those involved in the construction of beryllium components and their applications. This report is divided into five sub-sections: Atomic/Crystal Structure, Elastic Properties, Thermal Properties, Nuclear Properties, and Miscellaneous Properties. In searching through different sources for the various properties to be included in this report, inconsistencies were at times observed between these sources. In such cases, the values reported by the Handbook of Chemistry and Physics was usually used. In equations, except where indicated otherwise, temperature (T) is in degrees Kelvin.

  15. Nuclear magnetic resonance properties of lunar samples.

    NASA Technical Reports Server (NTRS)

    Kline, D.; Weeks, R. A.

    1972-01-01

    Nuclear magnetic resonance spectra of Na-23, Al-27, and P-31 in fines samples 10084,60 and 14163,168 and in crystalline rock samples 12021,55 and 14321,166, have been recorded over a range of frequencies up to 20 MHz. A shift in the field at which maximum absorption occurs for all of the spectra relative to the field at which maximum absorption occurs for terrestrial analogues is attributed to a sample-dependent magnetic field at the Na, Al, and P sites opposing the laboratory field. The magnitude of these fields internal to the samples is sample dependent and varies from 5 to 10 G. These fields do not correlate with the iron content of the samples. However, the presence of single-domain particles of iron distributed throughout the plagioclase fraction that contains the principal fraction of Na and Al is inferred from electron magnetic resonance spectra shapes.

  16. Properties of the yeast nuclear histone deacetylase.

    PubMed Central

    Sanchez del Pino, M M; Lopez-Rodas, G; Sendra, R; Tordera, V

    1994-01-01

    A nuclear histone deacetylase from yeast was partially purified and some of its characteristics were studied. Histone deacetylase activity was stimulated in vitro by high-mobility-group nonhistone chromatin proteins 1 and 2 and ubiquitin and inhibited by spermine and spermidine, whereas n-butyrate had no significant inhibitory effect. Like the mammalian enzyme, partially purified histone deacetylase from yeast was strongly inhibited by trichostatin A. However, in crude extract preparations the yeast enzyme was not inhibited and treatment with trichostatin in vivo did not show any effect, either on the histone acetylation level or on cell viability. At low ionic strength, the enzyme can be isolated as a complex of high molecular mass that is much less inhibited by trichostatin A than is partially purified histone deacetylase activity. Furthermore, radiolabelled oligonucleosomes were more efficiently deacetylated by the complex than by the low-molecular-mass form of the enzyme. The histone deacetylase activity was separated from a polyamine deacetylase activity and its specificity studied. Using h.p.l.c.-purified core histone species as substrate, histone deacetylase from yeast is able to deacetylate all core histones with a slight preference for H3. Our results support the idea that the yeast histone deacetylase may act as a high-molecular-mass complex in vivo. Images Figure 3 PMID:7980438

  17. 41 CFR 109-45.309-53 - Nuclear-related or proliferation sensitive property.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Nuclear-related or proliferation sensitive property. 109-45.309-53 Section 109-45.309-53 Public Contracts and Property Management... Personal Property § 109-45.309-53 Nuclear-related or proliferation sensitive property. Nuclear-related or...

  18. 41 CFR 109-45.309-53 - Nuclear-related or proliferation sensitive property.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Nuclear-related or proliferation sensitive property. 109-45.309-53 Section 109-45.309-53 Public Contracts and Property Management... Personal Property § 109-45.309-53 Nuclear-related or proliferation sensitive property. Nuclear-related or...

  19. 41 CFR 109-45.309-53 - Nuclear-related or proliferation sensitive property.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Nuclear-related or proliferation sensitive property. 109-45.309-53 Section 109-45.309-53 Public Contracts and Property Management... Personal Property § 109-45.309-53 Nuclear-related or proliferation sensitive property. Nuclear-related or...

  20. 41 CFR 109-45.309-53 - Nuclear-related or proliferation sensitive property.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Nuclear-related or proliferation sensitive property. 109-45.309-53 Section 109-45.309-53 Public Contracts and Property Management... Personal Property § 109-45.309-53 Nuclear-related or proliferation sensitive property. Nuclear-related or...

  1. 41 CFR 109-45.309-53 - Nuclear-related or proliferation sensitive property.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Nuclear-related or proliferation sensitive property. 109-45.309-53 Section 109-45.309-53 Public Contracts and Property Management... Personal Property § 109-45.309-53 Nuclear-related or proliferation sensitive property. Nuclear-related...

  2. Spectral nuclear properties of NLS1 galaxies

    NASA Astrophysics Data System (ADS)

    Schmidt, E. O.; Ferreiro, D.; Vega Neme, L.; Oio, G. A.

    2016-12-01

    Context. It is not yet well known whether narrow line Seyfert 1 (NLS1) galaxies follow the MBH - σ⋆ relation found for normal galaxies. Emission lines, such as [SII] or [OIII]λ5007, have been used as a surrogate of the stellar velocity dispersion and various results have been obtained. On the other hand, some active galactic nuclei (AGNs) have shown Balmer emission with an additional intermediate component (IC) besides the well-known narrow and broad lines. The properties of this IC have not yet been fully studied. Aims: In order to re-examine the location of NLS1 in the MBH - σ⋆ relation, we test some emission lines, such as the narrow component (NC) of Hα and the forbidden [NII]λλ6548,6584 and [SII]λλ6716,6731 lines, as replacements for σ⋆. On the other hand, we study the properties of the IC of Hα found in 14 galaxies of the sample to find a link between this component, the central engine, and the remaining lines. We also compare the emission among the broad component (BC) of Hα and those emitted at the narrow line region (NLR) to detect differences in the ionizing source in each emitting region. Methods: We have obtained and studied medium-resolution spectra (170 km s-1 FWHM at Hα) of 36 NLS1 galaxies in the optical range 5800-6800 Å. We performed a Gaussian decomposition of the Hα +[NII]λλ6548,6584 profile to study the distinct components of Hα and [NII] lines. We also measured the [SII] lines. Results: We obtained black hole (BH) masses in the range log (MBH/M⊙) = 5.4-7.5 for our sample. We found that, in general, most of the galaxies lie below the MBH - σ⋆ relation when the NC of Hα and [NII] lines are used as a surrogate of σ⋆. The objects are closer to the relation when [SII] lines are used. Nevertheless, the galaxies are still below this relation and we do not see a clear correlation between the BH masses and FWHM[SII]. Besides this, we found that 13 galaxies show an IC, most of which are in the velocity range 700-1500 km s

  3. 41 CFR 109-43.305-50 - Nuclear-related and proliferation-sensitive personal property.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Nuclear-related and proliferation-sensitive personal property. 109-43.305-50 Section 109-43.305-50 Public Contracts and Property... Excess § 109-43.305-50 Nuclear-related and proliferation-sensitive personal property. Nuclear-related and...

  4. 41 CFR 109-43.305-50 - Nuclear-related and proliferation-sensitive personal property.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Nuclear-related and proliferation-sensitive personal property. 109-43.305-50 Section 109-43.305-50 Public Contracts and Property... Excess § 109-43.305-50 Nuclear-related and proliferation-sensitive personal property. Nuclear-related and...

  5. 41 CFR 109-43.305-50 - Nuclear-related and proliferation-sensitive personal property.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Nuclear-related and proliferation-sensitive personal property. 109-43.305-50 Section 109-43.305-50 Public Contracts and Property... Excess § 109-43.305-50 Nuclear-related and proliferation-sensitive personal property. Nuclear-related and...

  6. 41 CFR 109-43.305-50 - Nuclear-related and proliferation-sensitive personal property.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Nuclear-related and proliferation-sensitive personal property. 109-43.305-50 Section 109-43.305-50 Public Contracts and Property... Excess § 109-43.305-50 Nuclear-related and proliferation-sensitive personal property. Nuclear-related and...

  7. 41 CFR 109-43.305-50 - Nuclear-related and proliferation-sensitive personal property.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Nuclear-related and proliferation-sensitive personal property. 109-43.305-50 Section 109-43.305-50 Public Contracts and Property... Excess § 109-43.305-50 Nuclear-related and proliferation-sensitive personal property. Nuclear-related...

  8. The effect of elastic properties of nuclear matter on nuclear fission

    SciTech Connect

    Bastrukov, S.I.; Molodtsova, I.V.; Yuldashbaeva, E.Kh.

    1994-07-01

    Spheroidal nuclear vibrations are considered using a macroscopic model based on the assumption that nuclear matter possesses the properties of elastic medium. Emphasis is laid on the analysis of instability of the quadrupole configuration. It is presumed that the onset of this instability is associated with the commencement of fission. The proposed fluid-dynamics model predicts the values of the parameters of nuclear fission that differ somewhat from the values given by the standard liquid drop-model. In particular, the obtained critical ratio Z{sup 2}/A, which characterizes the loss of stability of the quadrupole mode, is equal to 35. It follows from this estimate that fission induced by an external perturbation should be expected for nuclei (from the {beta}-stability valley) with A{>=}230. 16 refs.

  9. 41 CFR 109-43.307-52 - Nuclear-related or proliferation-sensitive personal property.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Nuclear-related or... Excess § 109-43.307-52 Nuclear-related or proliferation-sensitive personal property. (a) Recognizing that property disposal officials will not have the technical knowledge to identify nuclear-related and...

  10. 41 CFR 109-43.307-52 - Nuclear-related or proliferation-sensitive personal property.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Nuclear-related or... Excess § 109-43.307-52 Nuclear-related or proliferation-sensitive personal property. (a) Recognizing that property disposal officials will not have the technical knowledge to identify nuclear-related and...

  11. 41 CFR 109-43.307-52 - Nuclear-related or proliferation-sensitive personal property.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Nuclear-related or... Excess § 109-43.307-52 Nuclear-related or proliferation-sensitive personal property. (a) Recognizing that property disposal officials will not have the technical knowledge to identify nuclear-related and...

  12. 41 CFR 109-43.307-52 - Nuclear-related or proliferation-sensitive personal property.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Nuclear-related or... Excess § 109-43.307-52 Nuclear-related or proliferation-sensitive personal property. (a) Recognizing that property disposal officials will not have the technical knowledge to identify nuclear-related and...

  13. 41 CFR 109-43.307-52 - Nuclear-related or proliferation-sensitive personal property.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Nuclear-related or... Excess § 109-43.307-52 Nuclear-related or proliferation-sensitive personal property. (a) Recognizing that property disposal officials will not have the technical knowledge to identify nuclear-related...

  14. Quantitative properties of clustering within modern microscopic nuclear models

    SciTech Connect

    Volya, A.; Tchuvil’sky, Yu. M.

    2016-09-15

    A method for studying cluster spectroscopic properties of nuclear fragmentation, such as spectroscopic amplitudes, cluster form factors, and spectroscopic factors, is developed on the basis of modern precision nuclear models that take into account the mixing of large-scale shell-model configurations. Alpha-cluster channels are considered as an example. A mathematical proof of the need for taking into account the channel-wave-function renormalization generated by exchange terms of the antisymmetrization operator (Fliessbach effect) is given. Examples where this effect is confirmed by a high quality of the description of experimental data are presented. By and large, the method in question extends substantially the possibilities for studying clustering phenomena in nuclei and for improving the quality of their description.

  15. Distributional properties of stochastic shortest paths for smuggled nuclear material

    SciTech Connect

    Cuellar, Leticia; Pan, Feng; Roach, Fred; Saeger, Kevin J

    2011-01-05

    The shortest path problem on a network with fixed weights is a well studied problem with applications to many diverse areas such as transportation and telecommunications. We are particularly interested in the scenario where a nuclear material smuggler tries to succesfully reach herlhis target by identifying the most likely path to the target. The identification of the path relies on reliabilities (weights) associated with each link and node in a multi-modal transportation network. In order to account for the adversary's uncertainty and to perform sensitivity analysis we introduce random reliabilities. We perform some controlled experiments on the grid and present the distributional properties of the resulting stochastic shortest paths.

  16. Properties of nuclear matter from macroscopic-microscopic mass formulas

    NASA Astrophysics Data System (ADS)

    Wang, Ning; Liu, Min; Ou, Li; Zhang, Yingxun

    2015-12-01

    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.

  17. Bulk Properties of Nuclear Matter From Excitations of Nuclei

    SciTech Connect

    Shlomo, Shalom

    2007-10-26

    We consider the predictive power of Hartree-Fock (HF) approximation in determining properties of finite nuclei and thereby in extracting bulk properties of infinite nuclear matter (NM) by extrapolation. In particular, we review the current status of determining the value of NM incompressibility coefficient K, considering the most sensitive method of analyzing the recent accurate experimental data on excitation strengths of compression modes of nuclei within microscopic relativistic and non-relativistic theoretical models. We discuss the consequences of common violations of self-consistency in HF based random-phase-approximation calculations of strength functions and present results of highly accurate calculations of centroid energies and excitation cross sections of giant resonances. Explanations (resolutions) of long standing discrepancies in the value of K are presented.

  18. Nuclear Well Log Properties of Natural Gas Hydrate Reservoirs

    NASA Astrophysics Data System (ADS)

    Burchwell, A.; Cook, A.

    2015-12-01

    Characterizing gas hydrate in a reservoir typically involves a full suite of geophysical well logs. The most common method involves using resistivity measurements to quantify the decrease in electrically conductive water when replaced with gas hydrate. Compressional velocity measurements are also used because the gas hydrate significantly strengthens the moduli of the sediment. At many gas hydrate sites, nuclear well logs, which include the photoelectric effect, formation sigma, carbon/oxygen ratio and neutron porosity, are also collected but often not used. In fact, the nuclear response of a gas hydrate reservoir is not known. In this research we will focus on the nuclear log response in gas hydrate reservoirs at the Mallik Field at the Mackenzie Delta, Northwest Territories, Canada, and the Gas Hydrate Joint Industry Project Leg 2 sites in the northern Gulf of Mexico. Nuclear logs may add increased robustness to the investigation into the properties of gas hydrates and some types of logs may offer an opportunity to distinguish between gas hydrate and permafrost. For example, a true formation sigma log measures the thermal neutron capture cross section of a formation and pore constituents; it is especially sensitive to hydrogen and chlorine in the pore space. Chlorine has a high absorption potential, and is used to determine the amount of saline water within pore spaces. Gas hydrate offers a difference in elemental composition compared to water-saturated intervals. Thus, in permafrost areas, the carbon/oxygen ratio may vary between gas hydrate and permafrost, due to the increase of carbon in gas hydrate accumulations. At the Mallik site, we observe a hydrate-bearing sand (1085-1107 m) above a water-bearing sand (1107-1140 m), which was confirmed through core samples and mud gas analysis. We observe a decrease in the photoelectric absorption of ~0.5 barnes/e-, as well as an increase in the formation sigma readings of ~5 capture units in the water-bearing sand as

  19. Nuclear Technology Series. Course 15: Metallurgy and Metals Properties.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

  20. Nuclear Technology Series. Course 15: Metallurgy and Metals Properties.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

  1. Spectroscopic properties of nuclear skyrme energy density functionals.

    PubMed

    Tarpanov, D; Dobaczewski, J; Toivanen, J; Carlsson, B G

    2014-12-19

    We address the question of how to improve the agreement between theoretical nuclear single-particle energies (SPEs) and observations. Empirically, in doubly magic nuclei, the SPEs can be deduced from spectroscopic properties of odd nuclei that have one more or one less neutron or proton. Theoretically, bare SPEs, before being confronted with observations, must be corrected for the effects of the particle vibration coupling (PVC). In the present work, we determine the PVC corrections in a fully self-consistent way. Then, we adjust the SPEs, with PVC corrections included, to empirical data. In this way, the agreement with observations, on average, improves; nevertheless, large discrepancies still remain. We conclude that the main source of disagreement is still in the underlying mean fields, and not in including or neglecting the PVC corrections.

  2. NUCLEAR CONSTRAINTS ON PROPERTIES OF NEUTRON STAR CRUSTS

    SciTech Connect

    Xu Jun; Chen Liewen; Ma Hongru; Li Baoan E-mail: hrma@sjtu.edu.cn E-mail: Bao-An_Li@tamu-commerce.edu

    2009-06-01

    The transition density {rho} {sub t} and pressure P{sub t} at the inner edge separating the liquid core from the solid crust of neutron stars are systematically studied using a modified Gogny (MDI) and 51 popular Skyrme interactions within well established dynamical and thermodynamical methods. First of all, it is shown that the widely used parabolic approximation to the full equation of state (EOS) of isospin asymmetric nuclear matter may lead to huge errors in estimating the transition density and pressure, especially for stiffer symmetry energy functionals E {sub sym}({rho}), compared to calculations using the full EOS within both the dynamical and thermodynamical methods mainly because of the energy curvatures involved. Thus, fine details of the EOS of asymmetric nuclear matter are important for locating accurately the inner edge of the neutron star crust. Second, the transition density and pressure decrease roughly linearly with increasing slope parameter L of E {sub sym}({rho}) at normal nuclear matter density using the full EOS within both the dynamical and thermodynamical methods. It is also shown that the thickness, fractional mass, and moment of inertia of the neutron star crust are all very sensitive to the parameter L through the transition density {rho} {sub t} whether one uses the full EOS or its parabolic approximation. Moreover, it is shown that E {sub sym}({rho}) constrained in the same subsaturation density range as the neutron star crust by the isospin diffusion data in heavy-ion collisions at intermediate energies limits the transition density and pressure to 0.040 fm{sup -3} {<=}{rho} {sub t} {<=} 0.065 fm{sup -3} and 0.01 MeV fm{sup -3} {<=}P{sub t} {<=} 0.26 MeV fm{sup -3}, respectively. These constrained values for the transition density and pressure are significantly lower than their fiducial values currently used in the literature. Furthermore, the mass-radius relation and several other properties closely related to the neutron star crust

  3. Soft viscoelastic properties of nuclear actin age oocytes due to gravitational creep

    PubMed Central

    Feric, Marina; Broedersz, Chase P.; Brangwynne, Clifford P.

    2015-01-01

    The actin cytoskeleton helps maintain structural organization within living cells. In large X. laevis oocytes, gravity becomes a dominant force and is countered by a nuclear actin network that prevents liquid-like nuclear bodies from immediate sedimentation and coalescence. However, nuclear actin’s mechanical properties, and how they facilitate the stabilization of nuclear bodies, remain unknown. Using active microrheology, we find that nuclear actin forms a weak viscoelastic network, with a modulus of roughly 0.1 Pa. Embedded probe particles subjected to a constant force exhibit continuous displacement, due to viscoelastic creep. Gravitational forces also cause creep displacement of nuclear bodies, resulting in their asymmetric nuclear distribution. Thus, nuclear actin does not indefinitely support the emulsion of nuclear bodies, but only kinetically stabilizes them by slowing down gravitational creep to ~2 months. This is similar to the viability time of large oocytes, suggesting gravitational creep ages oocytes, with fatal consequences on long timescales. PMID:26577186

  4. Soft viscoelastic properties of nuclear actin age oocytes due to gravitational creep.

    PubMed

    Feric, Marina; Broedersz, Chase P; Brangwynne, Clifford P

    2015-11-18

    The actin cytoskeleton helps maintain structural organization within living cells. In large X. laevis oocytes, gravity becomes a dominant force and is countered by a nuclear actin network that prevents liquid-like nuclear bodies from immediate sedimentation and coalescence. However, nuclear actin's mechanical properties, and how they facilitate the stabilization of nuclear bodies, remain unknown. Using active microrheology, we find that nuclear actin forms a weak viscoelastic network, with a modulus of roughly 0.1 Pa. Embedded probe particles subjected to a constant force exhibit continuous displacement, due to viscoelastic creep. Gravitational forces also cause creep displacement of nuclear bodies, resulting in their asymmetric nuclear distribution. Thus, nuclear actin does not indefinitely support the emulsion of nuclear bodies, but only kinetically stabilizes them by slowing down gravitational creep to ~2 months. This is similar to the viability time of large oocytes, suggesting gravitational creep ages oocytes, with fatal consequences on long timescales.

  5. OPTICAL PROPERTIES OF HOST GALAXIES OF EXTRAGALACTIC NUCLEAR WATER MASERS

    SciTech Connect

    Zhu Guangtun; Zaw, Ingyin; Blanton, Michael R.; Greenhill, Lincoln J.

    2011-12-01

    We study the optical properties of the host galaxies of nuclear 22 GHz ({lambda} = 1.35 cm) water masers. To do so, we cross-match the galaxy sample surveyed for water maser emission (123 detections and 3806 non-detections) with the Sloan Digital Sky Survey (SDSS) low-redshift galaxy sample (z < 0.05). Out of 1636 galaxies with SDSS photometry, we identify 48 detections; out of the 1063 galaxies that also have SDSS spectroscopy, we identify 33 detections. We find that maser detection rate is higher at higher optical luminosity (M{sub B} ), larger velocity dispersion ({sigma}), and higher [O III] {lambda}5007 luminosity, with [O III] {lambda}5007 being the dominant factor. These detection rates are essentially the result of the correlations of isotropic maser luminosity with all three of these variables. These correlations are natural if maser strength increases with central black hole mass and the level of active galactic nucleus (AGN) activity. We also find that the detection rate is higher in galaxies with higher extinction. Based on these results, we propose that maser surveys seeking to efficiently find masers should rank AGN targets by extinction-corrected [O III] {lambda}5007 flux when available. This prioritization would improve maser detection efficiency, from an overall {approx}3% without pre-selection to {approx}16% for the strongest intrinsic [O III] {lambda}5007 emitters, by a factor of {approx}5.

  6. Optical Properties of Host Galaxies of Extragalactic Nuclear Water Masers

    NASA Astrophysics Data System (ADS)

    Zhu, Guangtun; Zaw, Ingyin; Blanton, Michael R.; Greenhill, Lincoln J.

    2011-12-01

    We study the optical properties of the host galaxies of nuclear 22 GHz (λ = 1.35 cm) water masers. To do so, we cross-match the galaxy sample surveyed for water maser emission (123 detections and 3806 non-detections) with the Sloan Digital Sky Survey (SDSS) low-redshift galaxy sample (z < 0.05). Out of 1636 galaxies with SDSS photometry, we identify 48 detections; out of the 1063 galaxies that also have SDSS spectroscopy, we identify 33 detections. We find that maser detection rate is higher at higher optical luminosity (MB ), larger velocity dispersion (σ), and higher [O III] λ5007 luminosity, with [O III] λ5007 being the dominant factor. These detection rates are essentially the result of the correlations of isotropic maser luminosity with all three of these variables. These correlations are natural if maser strength increases with central black hole mass and the level of active galactic nucleus (AGN) activity. We also find that the detection rate is higher in galaxies with higher extinction. Based on these results, we propose that maser surveys seeking to efficiently find masers should rank AGN targets by extinction-corrected [O III] λ5007 flux when available. This prioritization would improve maser detection efficiency, from an overall ~3% without pre-selection to ~16% for the strongest intrinsic [O III] λ5007 emitters, by a factor of ~5.

  7. Nuclear Quantum Effects on Aqueous Electron Attachment and Redox Properties.

    PubMed

    Rybkin, Vladimir V; VandeVondele, Joost

    2017-04-06

    Nuclear quantum effects (NQEs) on the reduction and oxidation properties of small aqueous species (CO2, HO2, and O2) are quantified and rationalized by first-principles molecular dynamics and thermodynamic integration. Vertical electron attachment, or electron affinity, and detachment energies (VEA and VDE) are strongly affected by NQEs, decreasing in absolute value by 0.3 eV going from a classical to a quantum description of the nuclei. The effect is attributed to NQEs that lessen the solvent response upon oxidation/reduction. The reduction of solvent reorganization energy is expected to be general for small solutes in water. In the thermodynamic integral that yields the free energy of oxidation/reduction, these large changes enter with opposite sign, and only a small net effect (0.1 eV) remains. This is not obvious for CO2, where the integrand is strongly influenced by NQEs due to the onset of interaction of the reduced orbital with the conduction band of the liquid during thermodynamic integration. We conclude that NQEs might not have to be included in the computation of redox potentials, unless high accuracy is needed, but are important for VEA and VDE calculations.

  8. 10 CFR 770.8 - May DOE transfer real property at defense nuclear facilities for economic development at less...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false May DOE transfer real property at defense nuclear facilities for economic development at less than fair market value? 770.8 Section 770.8 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.8 May DOE transfer real property at defense nuclear...

  9. 10 CFR 770.8 - May DOE transfer real property at defense nuclear facilities for economic development at less...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false May DOE transfer real property at defense nuclear facilities for economic development at less than fair market value? 770.8 Section 770.8 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.8 May DOE transfer real property at defense nuclear...

  10. Kaon properties in dense nuclear matter: are there experimental evidences of in medio effects?

    NASA Astrophysics Data System (ADS)

    Mangiarotti, A.

    2009-06-01

    Beyond the general interest for nuclear matter theory, the K- in medio mass modification could have important astrophysical consequences. Experimental evidences of how a nuclear medium affects K+ and K- properties will be summarised. To reach a firm conclusion about the K-, the missing information on the flow will be shown to be still relevant.

  11. Thermal and statistical properties of nuclei and nuclear systems

    SciTech Connect

    Moretto, L.G.; Wozniak, G.J.

    1989-07-01

    The term statistical decay, statistical or thermodynamic equilibrium, thermalization, temperature, etc., have been used in nuclear physics since the introduction of the compound nucleus (CN) concept, and they are still used, perhaps even more frequently, in the context of intermediate- and high-energy heavy-ion reactions. Unfortunately, the increased popularity of these terms has not made them any clearer, and more often than not one encounters sweeping statements about the alleged statisticity of a nuclear process where the statistical'' connotation is a more apt description of the state of the speaker's mind than of the nuclear reaction. It is our goal, in this short set of lectures, to set at least some ideas straight on this broad and beautiful subject, on the one hand by clarifying some fundamental concepts, on the other by presenting some interesting applications to actual physical cases. 74 refs., 38 figs.

  12. Effect of oxidation on physical properties of nuclear grade graphites

    NASA Astrophysics Data System (ADS)

    Matsuo, Hideto; Fujii, Kimio; Imai, Hisashi; Kurosawa, Takeshi

    1985-11-01

    Changes in thermal conductivity, coefficient of thermal expansion (CTE). electrical resistivity, and Young's modulus were measured for the two nuclear grade graphites IG-11 and H451 oxidized thermally in air at 723 K and by water vapor at 1123 K. Thermal conductivity, CTE and Young's modulus decreased and electrical resistivity increased owing to the oxidation. The changes were dependent on the graphites as well as the oxidation condition. The results were analyzed and discussed. Furthermore the changes in thermal shock resistance were discussed for the thermally oxidized nuclear grade graphites.

  13. Properties of nucleon in nuclear matter: once more

    NASA Astrophysics Data System (ADS)

    Azizi, K.; Er, N.

    2014-05-01

    We calculate the mass and residue of the nucleon in nuclear matter in the frame work of QCD sum rules using the nucleon's interpolating current with an arbitrary mixing parameter. We evaluate the effects of the nuclear medium on these quantities and compare the results obtained with the existing theoretical predictions. The results are also compared with those obtained in vacuum to find the shifts in the quantities under consideration. Our calculations show that these shifts in the mass and residue are about and , respectively.

  14. Three-body properties in nuclear matter at thermal equilibrium

    NASA Astrophysics Data System (ADS)

    Beyer, M.; Schadow, W.; Kuhrts, C.; Röpke, G.

    1999-09-01

    We derive three-body equations valid at finite densities and temperatures. The equations are based on the cluster mean field approach consistently including proper self-energy corrections and Pauli blocking. As an application we investigate the binding energies of triton and determine the Mott densities and momenta relevant for a many particle description of nuclear matter in a generalized Beth-Uhlenbeck approach. The method, however, is not restricted to nuclear physics problems but may also be relevant, e.g., to treat three-particle correlations in weakly doped semiconductors or strongly coupled dense plasmas.

  15. Method and apparatus for measuring nuclear magnetic properties

    DOEpatents

    Weitekamp, D.P.; Bielecki, A.; Zax, D.B.; Zilm, K.W.; Pines, A.

    1987-12-01

    A method for studying the chemical and structural characteristics of materials is disclosed. The method includes placement of a sample material in a high strength polarizing magnetic field to order the sample nuclei. The condition used to order the sample is then removed abruptly and the ordering of the sample allowed to evolve for a time interval. At the end of the time interval, the ordering of the sample is measured by conventional nuclear magnetic resonance techniques. 5 figs.

  16. Method and apparatus for measuring nuclear magnetic properties

    DOEpatents

    Weitekamp, Daniel P.; Bielecki, Anthony; Zax, David B.; Zilm, Kurt W.; Pines, Alexander

    1987-01-01

    A method for studying the chemical and structural characteristics of materials is disclosed. The method includes placement of a sample material in a high strength polarizing magnetic field to order the sample nucleii. The condition used to order the sample is then removed abruptly and the ordering of the sample allowed to evolve for a time interval. At the end of the time interval, the ordering of the sample is measured by conventional nuclear magnetic resonance techniques.

  17. Patenting the bomb: nuclear weapons, intellectual property, and technological control.

    PubMed

    Wellerstein, Alex

    2008-03-01

    During the course of the Manhattan Project, the U.S. government secretly attempted to acquire a monopoly on the patent rights for inventions used in the production of nuclear weapons and nuclear energy. The use of patents as a system of control, while common for more mundane technologies, would seem at first glance to conflict with the regimes of secrecy that have traditionally been associated with nuclear weapons. In explaining the origins and operations of the Manhattan Project patent system, though, this essay argues that the utilization of patents was an ad hoc attempt at legal control of the atomic bomb by Manhattan Project administrators, focused on the monopolistic aspects of the patent system and preexisting patent secrecy legislation. From the present perspective, using patents as a method of control for such weapons seems inadequate, if not unnecessary; but at the time, when the bomb was a new and essentially unregulated technology, patents played an important role in the thinking of project administrators concerned with meaningful postwar control of the bomb.

  18. Effects of neutrino trapping on thermodynamic properties of nuclear ``pasta''

    NASA Astrophysics Data System (ADS)

    Watanabe, G.; Iida, K.; Sato, K.

    2001-05-01

    Geometrical structure of matter at subnuclear densities is investigated in the presence of a degenerate gas of neutrinos as encountered in stellar collapse. The crystalline phases with spherical, cylindrical and planar nuclei as well as with spherical and cylindrical nuclear bubbles are considered by using a compressible liquid-drop model. This model allows for uncertainties in the lepton fraction YL in addition to those in the nuclear surface tension Esurf and in the proton chemical potential in bulk neutron matter μp(0). The phase diagrams obtained at zero temperature show that only the phases with rod-like and slab-like nuclei occur at typical values of YL, Esurf and μp(0), whereas the bubble phases, especially with spherical bubbles, are at best expected at hypothetically low values of YL and/or Esurf. For the rod-like and slab-like nuclei, thermally induced displacements are calculated from their respective elastic constants. It is found that at temperatures appropriate to supernova cores, thermal fluctuations would destroy a layered lattice of slab-like nuclei rather than a triangular lattice of rod-like nuclei, almost independently of the nuclear models and of the degree of the neutrino degeneracy.

  19. Reverse engineering nuclear properties from rare earth abundances in the r process

    NASA Astrophysics Data System (ADS)

    Mumpower, M. R.; McLaughlin, G. C.; Surman, R.; Steiner, A. W.

    2017-03-01

    The bulk of the rare earth elements are believed to be synthesized in the rapid neutron capture process or r process of nucleosynthesis. The solar r-process residuals show a small peak in the rare earths around A∼ 160, which is proposed to be formed dynamically during the end phase of the r process by a pileup of material. This abundance feature is of particular importance as it is sensitive to both the nuclear physics inputs and the astrophysical conditions of the main r process. We explore the formation of the rare earth peak from the perspective of an inverse problem, using Monte Carlo studies of nuclear masses to investigate the unknown nuclear properties required to best match rare earth abundance sector of the solar isotopic residuals. When nuclear masses are changed, we recalculate the relevant β-decay properties and neutron capture rates in the rare earth region. The feedback provided by this observational constraint allows for the reverse engineering of nuclear properties far from stability where no experimental information exists. We investigate a range of astrophysical conditions with this method and show how these lead to different predictions in the nuclear properties influential to the formation of the rare earth peak. We conclude that targeted experimental campaigns in this region will help to resolve the type of conditions responsible for the production of the rare earth nuclei, and will provide new insights into the longstanding problem of the astrophysical site(s) of the r process.

  20. Nuclear matter properties with nucleon-nucleon forces up to fifth order in the chiral expansion

    NASA Astrophysics Data System (ADS)

    Hu, Jinniu; Zhang, Ying; Epelbaum, Evgeny; Meißner, Ulf-G.; Meng, Jie

    2017-09-01

    The properties of nuclear matter are studied using state-of-the-art nucleon-nucleon forces up to fifth order in chiral effective field theory. The equations of state of symmetric nuclear matter and pure neutron matter are calculated in the framework of the Brueckner-Hartree-Fock theory. We discuss in detail the convergence pattern of the chiral expansion and the regulator dependence of the calculated equations of state and provide an estimation of the truncation uncertainty. For all employed values of the regulator, the fifth-order chiral two-nucleon potential is found to generate nuclear saturation properties similar to the available phenomenological high precision potentials. We also extract the symmetry energy of nuclear matter, which is shown to be quite robust with respect to the chiral order and the value of the regulator.

  1. Characterization of nuclear graphite elastic properties using laser ultrasonic methods

    NASA Astrophysics Data System (ADS)

    Zeng, Fan W.; Han, Karen; Olasov, Lauren R.; Gallego, Nidia C.; Contescu, Cristian I.; Spicer, James B.

    2015-05-01

    Laser ultrasonic methods have been used to characterize the elastic behaviors of commercially-available and legacy nuclear graphites. Since ultrasonic techniques are sensitive to various aspects of graphite microstructure including preferred grain orientation, microcrack orientation and porosity, laser ultrasonics is a candidate technique for monitoring graphite degradation and structural integrity in environments expected in high-temperature, gas-cooled nuclear reactors. Aspects of materials texture can be assessed by studying ultrasonic wavespeeds as a function of propagation direction and polarization. Shear wave birefringence measurements, in particular, can be used to evaluate elastic anisotropy. In this work, laser ultrasonic measurements of graphite moduli have been made to provide insight into the relationship between the microstructures and the macroscopic stiffnesses of these materials. In particular, laser ultrasonic measurements have been made using laser line sources to produce shear waves with specific polarizations. By varying the line orientation relative to the sample, shear wave birefringence measurements have been recorded. Results from shear wave birefringence measurements show that an isostatically molded graphite, such as PCIB, behaves isotropically, while an extruded graphite, such as H-451, displays significant ultrasonic texture. Graphites have complicated microstructures that depend on the manufacturing processes used, and ultrasonic texture in these materials could originate from grain orientation and preferred microcrack alignment. Effects on material isotropy due to service related microstructural changes are possible and the ultimate aim of this work is to determine the degree to which these changes can be assessed nondestructively using laser ultrasonics measurements.

  2. Nuclear Properties and Decay Data Chart of Nuclides.

    SciTech Connect

    OSORIO, V. B.

    2008-04-04

    Version 00 NUCHART displays nuclear decay data graphically on a PC and, includes a search routine for assigning gamma-ray energies to radionuclides. The numerical data included in NUCHART were taken from the online database "NUDAT" Version of March 1994. The following information is presented: (1) Nuclide information: for each nuclide, abundance, mass excess, (main) decay mode, half-life and uncertainty, branching ratio, decay Q; (2) decay radiation: for each nuclide, tables of radiation energy, intensity and equivalent dose for the 5 most intense decay radiations of beta+, beta-, conversion electrons, gammas, alphas and x-rays, including electron Augers; (3) adopted gammas: for each nuclide, table containing energy, relative intensity, energy level of the main gamma lines and year of publication in Nuclear Data Sheets; (4) search gamma energies: for a specified interval of gamma energies all know gamma lines and their nuclides are displayed; the database contains 132,000 gamma lines; (5) a search mode by specific nuclide is also available. For the latest data and online tools for viewing the data, see NuDat 2.4 on the NNDC and IAEA NDS websites: http://www.nndc.bnl.gov/ and http://www-nds.iaea.org/.

  3. Characterization of nuclear graphite elastic properties using laser ultrasonic methods

    SciTech Connect

    Zeng, Fan W; Han, Karen; Olasov, Lauren R; Gallego, Nidia C; Contescu, Cristian I; Spicer, James B

    2015-01-01

    Laser ultrasonic methods have been used to characterize the elastic behaviors of commercially-available and legacy nuclear graphites. Since ultrasonic techniques are sensitive to various aspects of graphite microstructure including preferred grain orientation, microcrack orientation and porosity, laser ultrasonics is a candidate technique for monitoring graphite degradation and structural integrity in environments expected in high-temperature, gas-cooled nuclear reactors. Aspects of materials texture can be assessed by studying ultrasonic wavespeeds as a function of propagation direction and polarization. Shear wave birefringence measurements, in particular, can be used to evaluate elastic anisotropy. In this work, laser ultrasonic measurements of graphite moduli have been made to provide insight into the relationship between the microstructures and the macroscopic stiffnesses of these materials. In particular, laser ultrasonic measurements have been made using laser line sources to produce shear waves with specific polarizations. By varying the line orientation relative to the sample, shear wave birefringence measurements have been recorded. Results from shear wave birefringence measurements show that an isostatically molded graphite, such as PCIB, behaves isotropically, while an extruded graphite, such as H-451, displays significant ultrasonic texture. Graphites have complicated microstructures that depend on the manufacturing processes used, and ultrasonic texture in these materials could originate from grain orientation and preferred microcrack alignment. Effects on material isotropy due to service related microstructural changes are possible and the ultimate aim of this work is to determine the degree to which these changes can be assessed nondestructively using laser ultrasonics measurements

  4. Unified description of equation of state and transport properties of nuclear matter

    SciTech Connect

    Benhar, Omar; Farina, Nicola; Valli, Marco; Fiorilla, Salvatore

    2008-10-13

    Correlated basis function perturbation theory and the formalism of cluster expansions have been recently employed to obtain an effective interaction from a state-of-the-art nucleon nucleon potential model. The approach based on the effective interaction allows for a consistent description of the nuclear matter ground state and nucleon-nucleon scattering in the nuclear medium. This paper reports the the results of numerical calculations of different properties of nuclear and neutron matter, including the equation of state and the shear viscosity and thermal conductivity transport coefficients, carried out using the effective interaction.

  5. Nuclear magnetic resonance spectral analysis and molecular properties of berberine

    NASA Astrophysics Data System (ADS)

    Huang, Ming-Ju; Lee, Ken S.; Hurley, Sharon J.

    An extensive theoretical study of berberine has been performed at the ab initio HF/6-31G**, HF/6-311G**, and B3LYP/6-311G** levels with and without solvent effects. The optimized structures are compared with X-ray data. We found that the optimized structures with solvent effects are in slightly better agreement with X-ray data than those without solvent effects. The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of berberine were calculated by using the gauge-independent atomic orbital (GIAO) (with and without solvent effects), CSGT, and IGAIM methods. The calculated chemical shifts were compared with the two-dimensional NMR experimental data. Overall, the calculated chemical shifts show very good agreement with the experimental results. The harmonic vibrational frequencies for berberine were calculated at the B3LYP/6-311G** level.

  6. Properties of zirconium carbide for nuclear fuel applications

    NASA Astrophysics Data System (ADS)

    Katoh, Yutai; Vasudevamurthy, Gokul; Nozawa, Takashi; Snead, Lance L.

    2013-10-01

    Zirconium carbide (ZrC) is a potential coating, oxygen-gettering, or inert matrix material for advanced high temperature reactor fuels. ZrC has demonstrated attractive properties for these fuel applications including excellent resistance against fission product corrosion and fission product retention capabilities. However, fabrication of ZrC results in a range of stable sub-stoichiometric and carbon-rich compositions with or without substantial microstructural inhomogeneity, textural anisotropy, and a phase separation, leading to variations in physical, chemical, thermal, and mechanical properties. The effects of neutron irradiation at elevated temperatures, currently only poorly understood, are believed to be substantially influenced by those compositional and microstructural features further adding complexity to understanding the key ZrC properties. This article provides a survey of properties data for ZrC, as required by the United States Department of Energy's advanced fuel programs in support of the current efforts toward fuel performance modeling and providing guidance for future research on ZrC for fuel applications.

  7. State-of-the-art review of materials properties of nuclear waste forms.

    SciTech Connect

    Mendel, J. E.; Nelson, R. D.; Turcotte, R. P.; Gray, W. J.; Merz, M. D.; Roberts, F. P.; Weber, W. J.; Westsik, Jr., J. H.; Clark, D. E.

    1981-04-01

    The Materials Characterization Center (MCC) was established at the Pacific Northwest Laboratory to assemble a standardized nuclear waste materials data base for use in research, systems and facility design, safety analyses, and waste management decisions. This centralized data base will be provided through the means of a Nuclear Waste Materials Handbook. The first issue of the Handbook will be published in the fall of 1981 in looseleaf format so that it can be updated as additional information becomes available. To ensure utmost reliability, all materials data appearing in the Handbook will be obtained by standard procedures defined in the Handbook and approved by an independent Materials Review Board (MRB) comprised of materials experts from Department of Energy laboratories and from universities and industry. In the interim before publication of the Handbook there is need for a report summarizing the existing materials data on nuclear waste forms. This review summarizes materials property data for the nuclear waste forms that are being developed for immobilization of high-level radioactive waste. It is intended to be a good representation of the knowledge concerning the properties of HLW forms as of March 1981. The table of contents lists the following topics: introduction which covers waste-form categories, and important waste-form materials properties; physical properties; mechanical properties; chemical durability; vaporization; radiation effects; and thermal phase stability.

  8. Recent studies of nuclear and chemical properties of elements 103, 104 and 105

    SciTech Connect

    Hoffman, D.C. . Dept. of Chemistry Lawrence Berkeley Lab., CA )

    1990-08-01

    Information obtained since 1983 on the nuclear and chemical properties of element 103, the last on the actinide series, and elements 104 and 105, at the beginning of the transactinide series, is reviewed. Their chemical properties are compared with their lanthanide and lighter group 4 and 5 homologs and evidence for possible relativistic effects is discussed. The current knowledge of the nuclear properties of these elements and how these affect of the study of chemical properties is discussed. Some of the challenges involved in the study of short-lived isotopes which can only be produced an atom-at-a-time'' at an appropriate accelerator and the prognosis for future studies of these and still heavier elements are considered. 40 refs., 4 figs.

  9. Status of geometry effects on structural nuclear composite properties

    SciTech Connect

    Will Windes; Y. Katoh; L.L. Snead; E. Lara-Curzio; C. Henagar, Jr.

    2005-09-01

    structural ceramic composites being considered for control rod applications within the VHTR design. While standard sized (i.e. 150-mm long or longer) test specimens can be used for baseline non-irradiated thermal creep studies, very small, compact, tensile specimens will be required for the irradiated creep studies. Traditionally, it is standard practice to use small, representative test samples in place of full-size components for an irradiated study. However, a real problem exists for scale-up of composite materials. Unlike monolithic materials, these composites are engineered from two distinct materials using complicated infiltration techniques to provide full density and maximum mechanical properties. The material properties may be significantly affected when the component geometry or size is changed. It must be demonstrated that the smaller test samples used in an irradiated study will adequately represent larger composite tubes used for control rod applications. To accomplish this, two different test programs are being implemented to establish that small, flat test specimens are representative of the mechanical response for large, cylindrical composite tubes: a size effect study and a geometry effect study.

  10. Damage dosimetry and embrittlement monitoring of nuclear pressure vessels in real time by magnetic properties measurement

    SciTech Connect

    Stubbins, J.F.; Ougouag, A.M.; Williams, J.G.

    1992-07-01

    The objective of this project is to develop a technique for real-time monitoring of neutron dose and of the onset and progression of embrittlement in operating nuclear pressure vessels. The technique relies on the measurement of magnetic properties of steel and other magnetic materials which are extremely sensitive to radiation-induced properties changes. The approach being developed here is innovative and unique. It promises to be readily applicable to all existing and planned reactor structures. The significance of this program is that it addresses a major concern in the operation of existing nuclear pressure vessels. The development of microscopic defect clusters during irradiation in the nuclear pressure vessel beltline region leads to an increase in material yield strength and a concomitant decrease in ductility, or ability to absorb energy in fracture (i.e. fracture toughness). This decrease in fracture toughness is alarming since it may impair the ability of the pressure vessel to resist fracture during unusual loading situations.

  11. Generator coordinate method and nuclear collective motions (VII): the preservation of symmetry properties

    SciTech Connect

    XU Gong-ou

    1985-01-01

    In order to preserve all the symmetry properties for the effective collective Hamiltonian obtained with the generator coordinate method, it is necessary for the trial wave function to have proper transformation properties. The generator coordinates should then transform in the same way as the represented collective operators. Also, the center-of-mass motion should be independent of the internal motion in conformity with the invariance of the nuclear Hamiltonian with respect to space rotation and Galilean transformation.

  12. The Thermal Properties of Asymmetric Nuclear Matter within the Extended Brueckner-Hartree-Fock Approach

    NASA Astrophysics Data System (ADS)

    Hassaneen, Khaled; Mansour, Hesham

    2017-02-01

    The single-particle potentials and other properties at absolute zero temperature in isospin asymmetric nuclear matter are investigated in the frame of an extended Brueckner theory. Also thermal quantities are calculated in asymmetric nuclear matter using CD-Bonn potential and the Urbana three-body forces (3BF). Also, the effects of the hole-hole contributions are investigated within the self-consistent Greens function approach. The inclusion of 3BF or the hole-hole contributions improves the predicted saturation property of symmetric nuclear matter within the Brueckner-Hartree-Fock approach and it leads to a significant stiffening of the density dependence of symmetry energy at high densities but the exact saturation point is not reproduced. This is of great importance in astrophysical calculation. A phenomenological term simulating the three-body interaction is introduced to assure the empirical saturation property. The hot properties of asymmetric nuclear matter such as the internal energy and the pressure are analyzed using T2-approximation method at low temperatures.

  13. Properties of two Lymantria dispar nuclear polyhedrosis virus isolates obtained from the microbial pesticide Gypchek

    Treesearch

    James M. Slavicek; John Podgwaite; Carita. Lanner-Herrera

    1992-01-01

    Two Lymantria dispar nuclear polyhedrosis virus isolates, 5-6 and A2-1, differing in the phenotypic characteristic of the number of viral occlusions in infected cells, were obtained from a production lot of the microbial pesticide Gypchek and several of their replication properties were investigated and compared. Budded virus titer produced in cell...

  14. 10 CFR 770.7 - What procedures are to be used to transfer real property at defense nuclear facilities for...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false What procedures are to be used to transfer real property at defense nuclear facilities for economic development? 770.7 Section 770.7 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.7...

  15. 10 CFR 770.6 - May interested persons and entities request that real property at defense nuclear facilities be...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false May interested persons and entities request that real property at defense nuclear facilities be transferred for economic development? 770.6 Section 770.6 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT §...

  16. 10 CFR 770.5 - How does DOE notify persons and entities that defense nuclear facility real property is available...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false How does DOE notify persons and entities that defense nuclear facility real property is available for transfer for economic development? 770.5 Section 770.5 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR...

  17. 10 CFR 770.8 - May DOE transfer real property at defense nuclear facilities for economic development at less...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false May DOE transfer real property at defense nuclear facilities for economic development at less than fair market value? 770.8 Section 770.8 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.8 May...

  18. 10 CFR 770.7 - What procedures are to be used to transfer real property at defense nuclear facilities for...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false What procedures are to be used to transfer real property at defense nuclear facilities for economic development? 770.7 Section 770.7 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.7...

  19. 10 CFR 770.5 - How does DOE notify persons and entities that defense nuclear facility real property is available...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false How does DOE notify persons and entities that defense nuclear facility real property is available for transfer for economic development? 770.5 Section 770.5 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR...

  20. 10 CFR 770.8 - May DOE transfer real property at defense nuclear facilities for economic development at less...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false May DOE transfer real property at defense nuclear facilities for economic development at less than fair market value? 770.8 Section 770.8 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.8 May...

  1. 10 CFR 770.6 - May interested persons and entities request that real property at defense nuclear facilities be...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false May interested persons and entities request that real property at defense nuclear facilities be transferred for economic development? 770.6 Section 770.6 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT §...

  2. 10 CFR 770.6 - May interested persons and entities request that real property at defense nuclear facilities be...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false May interested persons and entities request that real property at defense nuclear facilities be transferred for economic development? 770.6 Section 770.6 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT §...

  3. 10 CFR 770.7 - What procedures are to be used to transfer real property at defense nuclear facilities for...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false What procedures are to be used to transfer real property at defense nuclear facilities for economic development? 770.7 Section 770.7 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.7...

  4. 10 CFR 770.5 - How does DOE notify persons and entities that defense nuclear facility real property is available...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false How does DOE notify persons and entities that defense nuclear facility real property is available for transfer for economic development? 770.5 Section 770.5 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR...

  5. 10 CFR 770.8 - May DOE transfer real property at defense nuclear facilities for economic development at less...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false May DOE transfer real property at defense nuclear facilities for economic development at less than fair market value? 770.8 Section 770.8 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.8 May...

  6. 10 CFR 770.6 - May interested persons and entities request that real property at defense nuclear facilities be...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false May interested persons and entities request that real property at defense nuclear facilities be transferred for economic development? 770.6 Section 770.6 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.6...

  7. 10 CFR 770.5 - How does DOE notify persons and entities that defense nuclear facility real property is available...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false How does DOE notify persons and entities that defense nuclear facility real property is available for transfer for economic development? 770.5 Section 770.5 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC...

  8. 10 CFR 770.6 - May interested persons and entities request that real property at defense nuclear facilities be...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false May interested persons and entities request that real property at defense nuclear facilities be transferred for economic development? 770.6 Section 770.6 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.6...

  9. Distinct structural and mechanical properties of the nuclear lamina in Hutchinson-Gilford progeria syndrome.

    PubMed

    Dahl, Kris Noel; Scaffidi, Paola; Islam, Mohammad F; Yodh, Arjun G; Wilson, Katherine L; Misteli, Tom

    2006-07-05

    The nuclear lamina is a network of structural filaments, the A and B type lamins, located at the nuclear envelope and throughout the nucleus. Lamin filaments provide the nucleus with mechanical stability and support many basic activities, including gene regulation. Mutations in LMNA, the gene encoding A type lamins, cause numerous human diseases, including the segmental premature aging disease Hutchinson-Gilford progeria syndrome (HGPS). Here we show that structural and mechanical properties of the lamina are altered in HGPS cells. We demonstrate by live-cell imaging and biochemical analysis that lamins A and C become trapped at the nuclear periphery in HGPS patient cells. Using micropipette aspiration, we show that the lamina in HGPS cells has a significantly reduced ability to rearrange under mechanical stress. Based on polarization microscopy results, we suggest that the lamins are disordered in the healthy nuclei, whereas the lamins in HGPS nuclei form orientationally ordered microdomains. The reduced deformability of the HGPS nuclear lamina possibly could be due to the inability of these orientationally ordered microdomains to dissipate mechanical stress. Surprisingly, intact HGPS cells exhibited a degree of resistance to acute mechanical stress similar to that of cells from healthy individuals. Thus, in contrast to the nuclear fragility seen in lmna null cells, the lamina network in HGPS cells has unique mechanical properties that might contribute to disease phenotypes by affecting responses to mechanical force and misregulation of mechanosensitive gene expression.

  10. Distinct structural and mechanical properties of the nuclear lamina in Hutchinson–Gilford progeria syndrome

    PubMed Central

    Dahl, Kris Noel; Scaffidi, Paola; Islam, Mohammad F.; Yodh, Arjun G.; Wilson, Katherine L.; Misteli, Tom

    2006-01-01

    The nuclear lamina is a network of structural filaments, the A and B type lamins, located at the nuclear envelope and throughout the nucleus. Lamin filaments provide the nucleus with mechanical stability and support many basic activities, including gene regulation. Mutations in LMNA, the gene encoding A type lamins, cause numerous human diseases, including the segmental premature aging disease Hutchinson–Gilford progeria syndrome (HGPS). Here we show that structural and mechanical properties of the lamina are altered in HGPS cells. We demonstrate by live-cell imaging and biochemical analysis that lamins A and C become trapped at the nuclear periphery in HGPS patient cells. Using micropipette aspiration, we show that the lamina in HGPS cells has a significantly reduced ability to rearrange under mechanical stress. Based on polarization microscopy results, we suggest that the lamins are disordered in the healthy nuclei, whereas the lamins in HGPS nuclei form orientationally ordered microdomains. The reduced deformability of the HGPS nuclear lamina possibly could be due to the inability of these orientationally ordered microdomains to dissipate mechanical stress. Surprisingly, intact HGPS cells exhibited a degree of resistance to acute mechanical stress similar to that of cells from healthy individuals. Thus, in contrast to the nuclear fragility seen in lmna null cells, the lamina network in HGPS cells has unique mechanical properties that might contribute to disease phenotypes by affecting responses to mechanical force and misregulation of mechanosensitive gene expression. PMID:16801550

  11. Universally Conserved Relationships between Nuclear Shape and Cytoplasmic Mechanical Properties in Human Stem Cells

    PubMed Central

    Lozoya, Oswaldo A.; Gilchrist, Christopher L.; Guilak, Farshid

    2016-01-01

    The ability of cells to proliferate, differentiate, transduce extracellular signals and assemble tissues involves structural connections between nucleus and cytoskeleton. Yet, how the mechanics of these connections vary inside stem cells is not fully understood. To address those questions, we combined two-dimensional particle-tracking microrheology and morphological measures using variable reduction techniques to measure whether cytoplasmic mechanics allow for discrimination between different human adherent stem cell types and across different culture conditions. Here we show that nuclear shape is a quantifiable discriminant of mechanical properties in the perinuclear cytoskeleton (pnCSK) of various stem cell types. Also, we find the pnCSK is a region with different mechanical properties than elsewhere in the cytoskeleton, with heterogeneously distributed locations exhibiting subdiffusive features, and which obeys physical relations conserved among various stem cell types. Finally, we offer a prospective basis to discriminate between stem cell types by coupling perinuclear mechanical properties to nuclear shape. PMID:26976044

  12. Nuclear power plant containment metallic pressure boundary materials and plans for collecting and presenting their properties

    SciTech Connect

    Oland, C.B.

    1995-04-01

    A program is being conducted at the Oak Ridge National Laboratory (ORNL to assist the Nuclear Regulatory Commission (NRC)) in their assessment of the effects of degradation (primarily corrosion) on the structural capacity and leaktight integrity of metal containments and steel liners of reinforced concrete structures in nuclear power plants. One of the program objectives is to characterize and quantify manifestations of corrosion on the properties of steels used to construct containment pressure boundary components. This report describes a plan for use in collecting and presenting data and information on ferrous alloys permitted for use in construction of pressure retaining components in concrete and metal containments. Discussions about various degradation mechanisms that could potentially affect the mechanical properties of these materials are also included. Conclusions and recommendations presented in this report will be used to guide the collection of data and information that will be used to prepare a material properties data base for containment steels.

  13. Final technical report: Effects of water on properties of the simulated nuclear waste glasses

    SciTech Connect

    Li, H.; Tomozawa, M.

    1996-02-01

    For isolation of nuclear wastes through the vitrification process, waste slurry is mixed with borosilicate based glass and remelted at high temperature. During these processes, water can enter into the final waste glass. It is known that water in silica and silicate glasses changes various glass properties, such as chemical durability, viscosity and electrical conductivity. These properties are very important for processing and assuring the quality and safety controls of the waste glasses. The objective of this project was to investigate the effect of water in the simulated nuclear waste glasses on various glass properties, including chemical durability, glass transition temperature, liquidus temperature, viscosity and electrical conductivity. This report summarizes the results of this investigation conducted at Rensselaer during the past one year.

  14. Universally Conserved Relationships between Nuclear Shape and Cytoplasmic Mechanical Properties in Human Stem Cells

    NASA Astrophysics Data System (ADS)

    Lozoya, Oswaldo A.; Gilchrist, Christopher L.; Guilak, Farshid

    2016-03-01

    The ability of cells to proliferate, differentiate, transduce extracellular signals and assemble tissues involves structural connections between nucleus and cytoskeleton. Yet, how the mechanics of these connections vary inside stem cells is not fully understood. To address those questions, we combined two-dimensional particle-tracking microrheology and morphological measures using variable reduction techniques to measure whether cytoplasmic mechanics allow for discrimination between different human adherent stem cell types and across different culture conditions. Here we show that nuclear shape is a quantifiable discriminant of mechanical properties in the perinuclear cytoskeleton (pnCSK) of various stem cell types. Also, we find the pnCSK is a region with different mechanical properties than elsewhere in the cytoskeleton, with heterogeneously distributed locations exhibiting subdiffusive features, and which obeys physical relations conserved among various stem cell types. Finally, we offer a prospective basis to discriminate between stem cell types by coupling perinuclear mechanical properties to nuclear shape.

  15. Properties of colloidal corrosion products and their effects on nuclear plants. Final report. [PWR; BWR

    SciTech Connect

    Matijevic, E.

    1982-09-01

    Detailed results from the first two years of work on the properties of corrosion product oxides common to light water nuclear reactor systems are presented. A smaller companion volume describes the results in overview fashion. Numerous methods are described for producing these model oxides in forms making their study simpler, i.e., particles with uniform diameter and composition. A number of studies of particle adhesion to simulated power plant surfaces are described. The magnetic properties of hematite of various particle sizes are described - a property important to the use of electromagnetic filtration in LWRs.

  16. The effect of chromium oxide on the properties of simulated nuclear waste glasses

    SciTech Connect

    Vojtech, O.; Sussmilch, J.; Urbanec, Z.

    1996-02-01

    A study of the effect of chromium on the properties of selected glasses was performed in the frame of a Contract between Battelle, Pacific Northwest Laboratories and Nuclear Research Institute, ReZ. In the period from July 1994 to June 1995 two borosilicate glasses of special composition were prepared according to the PNL procedure and their physical and structural characteristics of glasses were studied. This Final Report contains a vast documentation on the properties of all glasses studied. For the preparation of the respective technology more detailed study of physico-chemical properties and crystallinity of investigated systems would be desirable.

  17. Chemical and nuclear properties of Rutherfordium (Element 104)

    SciTech Connect

    Kacher, Christian D.

    1995-10-30

    The chemical-properties of rutherfordium (Rf) and its group 4 homologs were studied by sorption on glass support surfaces coated with cobalt(II)ferrocyanide and by solvent extraction with tributylphosphate (TBP) and triisooctylamine (TIOA). The surface studies showed that the hydrolysis trend in the group 4 elements and the pseudogroup 4 element, lb, decreases in the order Rf>Zr≈Hf>Th. This trend was attributed to relativistic effects which predicted that Rf would be more prone to having a coordination number of 6 than 8 in most aqueous solutions due to a destabilization of the 6d5/2 shell and a stabilization of the 7pI/2 shell. This hydrolysis trend was confirmed in the TBP/HBr solvent extraction studies which showed that the extraction trend decreased in the order Zr>Hf>Rf?Ti for HBr, showing that Rf and Ti did not extract as well because they hydrolyzed more easily than Zr and Hf. The TIOA/HF solvent extraction studies showed that the extraction trend for the group 4 elements decreased in the order Ti>Zr≈Hf>Rf, in inverse order from the trend of ionic radii Rf>Zr≈Hf>Ti. An attempt was made to produce 263Rf (a) via the 248Cm(22Ne, α3n) reaction employing thenoyltrifluoroacetone (TTA) solvent extraction chemistry and (b) via the 249Bk(18O,4n) reaction employing the Automated Rapid Chemistry Apparatus (ARCA). In the TTA studies, 16 fissions were observed but were all attributed to 256Fm. No alpha events were observed in the Rf chemical fraction. A 0.2 nb upper limit production cross section for the 248Cm(22Ne, α3n)263Rf reaction was calculated assuming the 500-sec half-life reported previously by Czerwinski et al. [CZE92A].

  18. Sequence-encoded material properties dictate the structure and function of nuclear bodies.

    PubMed

    Weber, Stephanie C

    2017-06-01

    Concomitant with packaging the genome, the cell nucleus must also spatially organize the nucleoplasm. This complex mixture of proteins and nucleic acids partitions into a variety of phase-separated, membraneless organelles called nuclear bodies. Significant progress has been made in understanding the relationship between the material properties of nuclear bodies and their structural and functional consequences. Furthermore, the molecular basis of these condensed phases is beginning to emerge. Here, I review the latest work in this exciting field, highlighting recent advances and new challenges. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Temperature and density dependence of properties of nuclear matter deduced from heavy ion collisions

    SciTech Connect

    Shlomo, Shalom

    2010-11-24

    Heavy-ion collision experiments are often employed to determine properties of nuclear matter under extreme conditions of temperature and density. This has been the subject of many investigations in recent decades, since understanding the equation of state of hot nuclear matter is very important in the study supernovae, neutron stars and nuclei. We present a short and limited review of the theoretical and experimental status of determining the temperature and density of the disassembling hot nucleus from ratios of the yields of emitted fragments.

  20. International Nuclear Safety Center database on thermophysical properties of reactor materials

    SciTech Connect

    Fink, J.K.; Sofu, T.; Ley, H.

    1997-08-01

    The International Nuclear Safety Center (INSC) database has been established at Argonne National Laboratory to provide easily accessible data and information necessary to perform nuclear safety analyses and to promote international collaboration through the exchange of nuclear safety information. The INSC database, located on the World Wide Web at http://www.insc.anl.gov, contains critically assessed recommendations for reactor material properties for normal operating conditions, transients, and severe accidents. The initial focus of the database is on thermodynamic and transport properties of materials for water reactors. Materials that are being included in the database are fuel, absorbers, cladding, structural materials, coolant, and liquid mixtures of combinations of UO{sub 2}, ZrO{sub 2}, Zr, stainless steel, absorber materials, and concrete. For each property, the database includes: (1) a summary of recommended equations with uncertainties; (2) a detailed data assessment giving the basis for the recommendations, comparisons with experimental data and previous recommendations, and uncertainties; (3) graphs showing recommendations, uncertainties, and comparisons with data and other equations; and (4) property values tabulated as a function of temperature.

  1. Sigma omega meson coupling and properties of nuclei and nuclear matter

    NASA Astrophysics Data System (ADS)

    Haidari, Maryam M.; Sharma, Madan M.

    2008-05-01

    We have constructed a Lagrangian model with a coupling of σ and ω mesons in the relativistic mean-field theory. Properties of finite nuclei and nuclear matter are explored with the new Lagrangian model SIG-OM. The study shows that an excellent description of binding energies and charge radii of nuclei over a large range of isospin is achieved with SIG-OM. With an incompressibility of nuclear matter K=265 MeV, it is also able to describe the breathing-mode isoscalar giant monopole resonance energies appropriately. It is shown that the high-density behaviour of the equation of state of nuclear and neutron matter with the σ-ω coupling is much softer than that of the non-linear scalar coupling model.

  2. 10 CFR 770.7 - What procedures are to be used to transfer real property at defense nuclear facilities for...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false What procedures are to be used to transfer real property at defense nuclear facilities for economic development? 770.7 Section 770.7 Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.7 What procedures are to be used to transfer real property...

  3. Dynamic properties of nuclear pore complex proteins in gp210 deficient cells.

    PubMed

    Eriksson, Charlotta; Rustum, Cecilia; Hallberg, Einar

    2004-08-13

    Gp210, an integral membrane protein of the nuclear pore complex (NPC), is believed to be involved in NPC biogenesis. To test this hypothesis, we have investigated dynamic properties of the NPC and distribution of NPC proteins in NIH/3T3 cells lacking gp210. POM121 (the other integral NPC protein) and NUP107 (of the NUP107/160 complex) were correctly distributed at the nuclear pores in the absence of gp210. Furthermore, fluorescence recovery after photobleaching experiments showed that POM121 and NUP107 remained stably associated at the NPCs. We conclude that gp210 cannot be required for incorporation of POM121 or NUP107 or be required for maintaining NPC stability.

  4. Effect of oxidation on physical properties of neutron irradiated nuclear grade graphite

    NASA Astrophysics Data System (ADS)

    Matsuo, Hideto

    1986-04-01

    Changes in thermal conductivity, electrical resistivity and Young's modulus due to thermal oxidation in air were studied for the neutron irradiated nuclear grade graphite IG-11. Samples were irradiated and then oxidized in air at 450°C up to the maximum weight loss of 27%. Neutron irradiation caused the increases of the rate of oxidation in air, electrical resistivity and Young's modulus, and the decrease of thermal conductivity as well. Subsequent oxidation led to the results of the increase of electrical resistivity, and the decreases of Young's modulus and thermal conductivity. An analytical expression was given to the present experimental results, and the tendencies of the changes in the properties of neutron irradiated nuclear grade graphite due to the oxidation were clarified to be the same as those of unirradiated samples.

  5. Approach to modify the properties of titanium alloys for use in nuclear industry

    NASA Astrophysics Data System (ADS)

    Bilobrov, Iurii; Trachevsky, Vladimir

    2011-08-01

    This article discusses the metallurgical aspects of the modification of titanium alloys for use in the nuclear industry in the future. Irradiation leads to hardening, plastic instability and reduction in fracture toughness in Ti alloys. Sintered compositions Ti-6Al-4V, Ti-6Al-4V/LaB 6 have shown methods to reduce embrittlement. Residual porosity may serve as a temporary storage of products of nuclear decay H and He. High uniformity of the element distribution reduces the number of places predisposed to defect cluster formation. The plasticity reserve of Ti-6Al-4V/LaB 6 in comparison with international standards is ≈10%. The boron compounds to the partial absorption of neutrons fill the volume of residual pores in the material without degrading the properties of the matrix Ti-6Al-4V/LaB 6 alloy.

  6. Diffusion, Thermal Properties and Chemical Compatibilities of Select MAX Phases with Materials For Advanced Nuclear Systems

    SciTech Connect

    Barsoum, Michel; Bentzel, Grady; Tallman, Darin J.; Sindelar, Robert; Garcia-Diaz, Brenda; Hoffman, Elizabeth

    2016-04-04

    The demands of Gen IV nuclear power plants for long service life under neutron irradiation at high temperature are severe. Advanced materials that would withstand high temperatures (up to 1000+ ºC) to high doses in a neutron field would be ideal for reactor internal structures and would add to the long service life and reliability of the reactors. The objective of this work is to investigate the chemical compatibility of select MAX with potential materials that are important for nuclear energy, as well as to measure the thermal transport properties as a function of neutron irradiation. The chemical counterparts chosen for this work are: pyrolytic carbon, SiC, U, Pd, FLiBe, Pb-Bi and Na, the latter 3 in the molten state. The thermal conductivities and heat capacities of non-irradiated MAX phases will be measured.

  7. Magnetic hysteresis properties of neutron-irradiated VVER440-type nuclear reactor pressure vessel steels

    NASA Astrophysics Data System (ADS)

    Kobayashi, S.; Gillemot, F.; Horváth, Á.; Székely, R.; Horváth, M.

    2012-11-01

    The development of non-destructive evaluation methods for irradiation embrittlement in nuclear reactor pressure vessel steels has a key role for safe and long-term operation of nuclear power plants. In this study, we have investigated the effect of neutron irradiation on base and weld metals of Russian VVER440-type reactor pressure vessel steels by measurements of magnetic minor hysteresis loops. A minor-loop coefficient, which is obtained from a scaling power-law relation of minor-loop parameters and is a sensitive indicator of internal stress, is found to change with neutron fluence for both metals. While the coefficient for base metal exhibits a local maximum at low fluence and a subsequent slow decrease, that for weld metal monotonically decreases with fluence. The observed results are explained by competing mechanisms of nanoscale defect formation and recovery, among which the latter process plays a dominant role for magnetic property changes in weld metal due to its ferritic microstructure.

  8. Towards the improvement of spin-isospin properties in nuclear energy density functionals

    NASA Astrophysics Data System (ADS)

    Roca-Maza, X.; Colò, G.; Liang, H. Z.; Meng, J.; Ring, P.; Sagawa, H.; Zhao, P. W.

    2016-06-01

    We address the problem of improving existing nuclear Energy Density Functionals (EDFs) in the spin-isospin channel. For that, we propose two different ways. The first one is to carefully take into account in the fitting protocol some of the key ground state properties for an accurate description of the most studied spin-isospin resonances: the Gamow-Teller Resonance (GTR) [1]. The second consists in providing a strategy to build local covariant EDF keeping the main features from their non-local counterparts [2]. The RHF model based on a Lagrangian where heavy mesons carry the nuclear effective interaction have been shown to be successful in the description of spin-isospin resonances [3].

  9. NES-REBS: A novel nuclear export signal prediction method using regular expressions and biochemical properties.

    PubMed

    Wu, Tingfang; Wang, Xun; Zhang, Zheng; Gong, Faming; Song, Tao; Chen, Zhihua; Zhang, Pan; Zhao, Yang

    2016-06-01

    A nuclear export signal (NES) is a protein localization signal, which is involved in binding of cargo proteins to nuclear export receptor, thus contributes to regulate localization of cellular proteins. Consensus sequences of NES have been used to detect NES from protein sequences, but suffer from poor predictive power. Some recent peering works were proposed to use biochemical properties of experimental verified NES to refine NES candidates. Those methods can achieve high prediction rates, but their execution time will become unacceptable for large-scale NES searching if too much properties are involved. In this work, we developed a novel computational approach, named NES-REBS, to search NES from protein sequences, where biochemical properties of experimental verified NES, including secondary structure and surface accessibility, are utilized to refine NES candidates obtained by matching popular consensus sequences. We test our method by searching 262 experimental verified NES from 221 NES-containing protein sequences. It is obtained that NES-REBS runs in 2-3[Formula: see text]mins and performs well by achieving precision rate 47.2% and sensitivity 54.6%.

  10. 10 CFR 770.7 - What procedures are to be used to transfer real property at defense nuclear facilities for...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false What procedures are to be used to transfer real property... ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC DEVELOPMENT § 770.7 What... congressional defense committees through the Secretary of Energy. (d) Transfer. After the congressional...

  11. The properties of nuclear matter with lattice NN potential in relativistic Brueckner-Hartree-Fock theory

    PubMed Central

    Hu, Jinniu; Toki, Hiroshi; Shen, Hong

    2016-01-01

    We study the properties of nuclear matter with lattice nucleon-nucleon (NN) potential in the relativistic Brueckner-Hartree-Fock (RBHF) theory. To use this potential in such a microscopic many-body theory, we firstly have to construct a one-boson-exchange potential (OBEP) based on the latest lattice NN potential. Three mesons, pion, σ meson, and ω meson, are considered. Their coupling constants and cut-off momenta are determined by fitting the on-shell behaviors and phase shifts of the lattice force, respectively. Therefore, we obtain two parameter sets of the OBEP potential (named as LOBEP1 and LOBEP2) with these two fitting ways. We calculate the properties of symmetric and pure neutron matter with LOBEP1 and LOBEP2. In non-relativistic Brueckner-Hartree-Fock case, the binding energies of symmetric nuclear matter are around −3 and −5 MeV at saturation density, while it becomes −8 and −12 MeV in relativistic framework with 1S0, 3S1, and 3D1 channels using our two parameter sets. For the pure neutron matter, the equations of state in non-relativistic and relativistic cases are very similar due to only consideration 1S0 channel with isospin T = 1 case. PMID:27752124

  12. The properties of nuclear matter with lattice NN potential in relativistic Brueckner-Hartree-Fock theory

    NASA Astrophysics Data System (ADS)

    Hu, Jinniu; Toki, Hiroshi; Shen, Hong

    2016-10-01

    We study the properties of nuclear matter with lattice nucleon-nucleon (NN) potential in the relativistic Brueckner-Hartree-Fock (RBHF) theory. To use this potential in such a microscopic many-body theory, we firstly have to construct a one-boson-exchange potential (OBEP) based on the latest lattice NN potential. Three mesons, pion, σ meson, and ω meson, are considered. Their coupling constants and cut-off momenta are determined by fitting the on-shell behaviors and phase shifts of the lattice force, respectively. Therefore, we obtain two parameter sets of the OBEP potential (named as LOBEP1 and LOBEP2) with these two fitting ways. We calculate the properties of symmetric and pure neutron matter with LOBEP1 and LOBEP2. In non-relativistic Brueckner-Hartree-Fock case, the binding energies of symmetric nuclear matter are around ‑3 and ‑5 MeV at saturation density, while it becomes ‑8 and ‑12 MeV in relativistic framework with 1S0, 3S1, and 3D1 channels using our two parameter sets. For the pure neutron matter, the equations of state in non-relativistic and relativistic cases are very similar due to only consideration 1S0 channel with isospin T = 1 case.

  13. Nuclear microprobe studies of the electronic transport properties of cadmium zinc telluride (CZT) radiation detectors

    NASA Astrophysics Data System (ADS)

    Vizkelethy, Gyorgy; Doyle, Barney L.; Walsh, David S.; James, Ralph B.

    2000-11-01

    Ion Beam Induced Charge Collection (IBICC) is a proven albeit relatively new method to measure the electronic transport properties of room temperature radiation detectors. Using an ion microbeam, the charge collection efficiency of CZT detectors can be mapped with submicron resolution and maps of the electron mobility and lifetime can be calculated. The nuclear microprobe can be used not only for characterizing detectors but also with the use of Time Resolved IBICC (TRIBICC) and lateral IBICC/TRIBICC we can deduce information about the electron and hole mobility and lifetime profiles, and about the variation of electric field along the detectors' axes. The Sandia Nuclear Microprobe has been and is being used routinely to characterize CZT detectors and measure their electronic transport properties. In this paper we will present the results of these measurements for different detectors. Furthermore the damage effects caused by the probing beam will be discussed and a simple model will be presented to explain the characteristic charge collection efficiency pattern observed after high dose irradiation.

  14. Nuclear fuel cycle waste stream immobilization with cermets for improved thermal properties and waste consolidation

    NASA Astrophysics Data System (ADS)

    Ortega, Luis H.; Kaminski, Michael D.; Zeng, Zuotao; Cunnane, James

    2013-07-01

    In the pursuit of methods to improve nuclear waste form thermal properties and combine potential nuclear fuel cycle wastes, a bronze alloy was combined with an alkali, alkaline earth metal bearing ceramic to form a cermet. The alloy was prepared from copper and tin (10 mass%) powders. Pre-sintered ceramic consisting of cesium, strontium, barium and rubidium alumino-silicates was mixed with unalloyed bronze precursor powders and cold pressed to 300 × 103 kPa, then sintered at 600 °C and 800 °C under hydrogen. Cermets were also prepared that incorporated molybdenum, which has a limited solubility in glass, under similar conditions. The cermet thermal conductivities were seven times that of the ceramic alone. These improved thermal properties can reduce thermal gradients within the waste forms thus lowering internal temperature gradients and thermal stresses, allowing for larger waste forms and higher waste loadings. These benefits can reduce the total number of waste packages necessary to immobilize a given amount of high level waste and immobilize troublesome elements.

  15. Transport properties of isospin asymmetric nuclear matter using the time-dependent Hartree-Fock method

    NASA Astrophysics Data System (ADS)

    Umar, A. S.; Simenel, C.; Ye, W.

    2017-08-01

    Background: The study of deep-inelastic reactions of nuclei provides a vehicle to explore nuclear transport phenomena for a full range of equilibration dynamics. These investigations provide us the ingredients to model such phenomena and help answer important questions about the nuclear equation of state and its evolution as a function of neutron-to-proton (N /Z ) ratio. Purpose: The motivation is to examine the real-time dynamics of nuclear transport phenomena and its dependence on N /Z asymmetry from a microscopic point of view to avoid any pre-conceived assumptions about the involved processes. Method: The time-dependent Hartree-Fock (TDHF) method in full three dimensions is employed to calculate deep-inelastic reactions of 78Kr+208Pb and 92Kr+208Pb systems at 8.5 MeV/nucleon. The impact parameter and energy-loss dependence of relevant observables are calculated. In addition, the density-constrained TDHF method is used to compute excitation energies of the primary fragments. The statistical deexcitation code gemini is utilized to examine the final reaction products. Results: The kinetic energy loss and sticking times as a function of impact parameter are calculated. The final properties of the fragments (charge, mass, scattering angle, and kinetic energy) are computed. Their evolution as a function of energy loss is studied and various intra-relations are investigated. The fragment excitation energy sharing is computed. Conclusions: We find a smooth dependence of the energy loss, Eloss, on the impact parameter for both systems. However, the transfer properties for low Eloss values are very different for the two systems but become similar in the higher Eloss regime. The mean lifetime of the charge equilibration process, obtained from the final (N -Z )/A value of the fragments, is shown to be ˜0.5 zs. This value is slightly larger than (but of the same order as) the value obtained from reactions at Fermi energies.

  16. Considerations of Alloy 617 Application in the Gen IV Nuclear Reactor Systems - Part II: Metallurgical Property Challenges

    SciTech Connect

    Ren, Weiju

    2010-01-01

    Alloy 617 is currently considered as a leading candidate material for high temperature components in the Gen IV Nuclear Reactor Systems. Because of the unprecedented severe working conditions beyond its commercial service experience required by the Gen IV systems, the alloy faces various challenges in both mechanical and metallurgical properties. Following a previous paper discussing the mechanical property challenges, this paper is focused on the challenges and issues in metallurgical properties of the alloy for the intended nuclear application. Considerations are given in details about its metallurgical stability and aging evolution, aging effects on mechanical properties, potential Co hazard, and internal oxidation. Some research and development activities are suggested with discussions on viability to satisfy the Gen IV Nuclear Reactor System needs.

  17. Comparison of Property-Oriented Basis Sets for the Computation of Electronic and Nuclear Relaxation Hyperpolarizabilities.

    PubMed

    Zaleśny, Robert; Baranowska-Łączkowska, Angelika; Medveď, Miroslav; Luis, Josep M

    2015-09-08

    In the present work, we perform an assessment of several property-oriented atomic basis sets in computing (hyper)polarizabilities with a focus on the vibrational contributions. Our analysis encompasses the Pol and LPol-ds basis sets of Sadlej and co-workers, the def2-SVPD and def2-TZVPD basis sets of Rappoport and Furche, and the ORP basis set of Baranowska-Łączkowska and Łączkowski. Additionally, we use the d-aug-cc-pVQZ and aug-cc-pVTZ basis sets of Dunning and co-workers to determine the reference estimates of the investigated electric properties for small- and medium-sized molecules, respectively. We combine these basis sets with ab initio post-Hartree-Fock quantum-chemistry approaches (including the coupled cluster method) to calculate electronic and nuclear relaxation (hyper)polarizabilities of carbon dioxide, formaldehyde, cis-diazene, and a medium-sized Schiff base. The primary finding of our study is that, among all studied property-oriented basis sets, only the def2-TZVPD and ORP basis sets yield nuclear relaxation (hyper)polarizabilities of small molecules with average absolute errors less than 5.5%. A similar accuracy for the nuclear relaxation (hyper)polarizabilites of the studied systems can also be reached using the aug-cc-pVDZ basis set (5.3%), although for more accurate calculations of vibrational contributions, i.e., average absolute errors less than 1%, the aug-cc-pVTZ basis set is recommended. It was also demonstrated that anharmonic contributions to first and second hyperpolarizabilities of a medium-sized Schiff base are particularly difficult to accurately predict at the correlated level using property-oriented basis sets. For instance, the value of the nuclear relaxation first hyperpolarizability computed at the MP2/def2-TZVPD level of theory is roughly 3 times larger than that determined using the aug-cc-pVTZ basis set. We link the failure of the def2-TZVPD basis set with the difficulties in predicting the first-order field

  18. Local fracture properties and dissimilar weld integrity in nuclear power plants

    NASA Astrophysics Data System (ADS)

    Wang, Guozhen; Wang, Haitao; Xuan, Fuzhen; Tu, Shantung; Liu, Changjun

    2013-09-01

    In this paper, the local fracture properties in a Alloy52M dissimilar metal welded joint (DMWJ) between A508 ferritic steel and 316 L stainless steel in nuclear power plants were investigated by using the single-edge notched bend (SENB) specimens, and their use in integrity assessment of DMWJ structures was analyzed. The results show that the local fracture resistance in the DMWJ is determined by local fracture mechanism, and which is mainly related to the microstructures and local strength mismatches of materials at the crack locations. The initial cracks always grow towards the materials with lower strength, and the crack path deviation is mainly controlled by the local strength mismatch. If the local fracture properties could not be used for cracks in the heat affected zones (HAZs), interface and near interface zones, the use of the fracture properties ( J-resistance curves) of base metals or weld metals following present codes will unavoidably produce non-conservative (unsafe) or excessive conservative assessment results. In most cases, the assessment results will be potentially unsafe. Therefore, it is recommended to obtain and use local mechanical and fracture properties in the integrity assessment of DMWJs.

  19. Chemical and nuclear properties of lawrencium (element 103) and hahnium (element 105)

    SciTech Connect

    Henderson, R.A.

    1990-09-10

    The chemical and nuclear properties of Lr and Ha have been studied, using 3-minute {sup 260}Lr and 35-second {sup 262}Ha. The crystal ionic radius of Lr{sup 3+} was determined by comparing its elution position from a cation-exchange resin column with those of lanthanide elements having known ionic radii. Comparisons are made to the ionic radii of the heavy actinides, Am{sup 3+} through Es{sup 3+}, obtained by x-ray diffraction methods, and to Md{sup 3+} and Fm{sup 3+} which were determined in the same manner as Lr{sup 3+}. The hydration enthalpy of {minus}3622 kJ/mol was calculated from the crystal ionic radius using an empirical form of the Born equation. Comparisons to the spacings between the ionic radii of the heaviest members of the lanthanide series show that the 2Z spacing between Lr{sup 3+} and Md{sup 3+} is anomalously small, as the ionic radius of Lr{sup 3+} of 0.0886 nm is significantly smaller than had been expected. The chemical properties of Ha were determined relative to the lighter homologs in group 5, Nb and Ta. Group 4 and group 5 tracer activities, as well as Ha, were absorbed onto glass surfaces as a first step toward the determination of the chemical properties of Ha. Ha was found to adsorb on surfaces, a chemical property unique to the group 5 elements, and as such demonstrates that Ha has the chemical properties of a group 5 element. A solvent extraction procedure was adapted for use as a micro-scale chemical procedure to examine whether or not Ha displays eka-Ta-like chemical under conditions where Ta will be extracted into the organic phase and Nb will not. Under the conditions of this experiment Ha did not extract, and does not show eka-Ta-like chemical properties.

  20. 73Ge-Nuclear Magnetic Resonance/Nuclear Quadrupole Resonance Investigation of Magnetic Properties of URhGe

    NASA Astrophysics Data System (ADS)

    Kotegawa, Hisashi; Fukumoto, Kenta; Toyama, Toshihiro; Tou, Hideki; Harima, Hisatomo; Harada, Atsushi; Kitaoka, Yoshio; Haga, Yoshinori; Yamamoto, Etsuji; Ōnuki, Yoshichika; Itoh, Kohei M.; Haller, Eugene E.

    2015-05-01

    We report on the 73Ge-nuclear magnetic resonance (NMR)/nuclear quadrupole resonance (NQR) results for the ferromagnetic (FM) superconductor URhGe. The magnitude and direction of the internal field, Hint, and the parameters of the electric field gradient at the Ge site were determined experimentally. By using powdered polycrystalline samples oriented by different methods, the field dependences of NMR shift and nuclear spin relaxation rates for H0 || c (easy axis) and H0 || b were obtained. From the NMR shifts for H0 || b, we confirmed a gradual suppression of the Curie temperature and observed a phase separation near the spin reorientation. The observation of the phase separation gives microscopic evidence that the spin reorientation under H0 || b is of first order at low temperatures. The nuclear spin-lattice relaxation rate 1/T1 indicates that the magnetic fluctuations are suppressed for H0 || c, whereas the fluctuations remain strongly for H0 || b. The enhancements of both 1/T1T and the nuclear spin-spin relaxation rate 1/T2 for H0 || b toward the spin reorientation field suggest that the field-induced superconductivity in URhGe emerges under the magnetic fluctuations along the b- and c-axes.

  1. Muscular Dystrophy Mutations Impair the Nuclear Envelope Emerin Self-assembly Properties.

    PubMed

    Herrada, Isaline; Samson, Camille; Velours, Christophe; Renault, Louis; Östlund, Cecilia; Chervy, Pierre; Puchkov, Dmytro; Worman, Howard J; Buendia, Brigitte; Zinn-Justin, Sophie

    2015-12-18

    More than 100 genetic mutations causing X-linked Emery-Dreifuss muscular dystrophy have been identified in the gene encoding the integral inner nuclear membrane protein emerin. Most mutations are nonsense or frameshift mutations that lead to the absence of emerin in cells. Only very few cases are due to missense or short in-frame deletions. Molecular mechanisms explaining the corresponding emerin variants' loss of function are particularly difficult to identify because of the mostly intrinsically disordered state of the emerin nucleoplasmic region. We now demonstrate that this EmN region can be produced as a disordered monomer, as revealed by nuclear magnetic resonance, but rapidly self-assembles in vitro. Increases in concentration and temperature favor the formation of long curvilinear filaments with diameters of approximately 10 nm, as observed by electron microscopy. Assembly of these filaments can be followed by fluorescence through Thioflavin-T binding and by Fourier-transform Infrared spectrometry through formation of β-structures. Analysis of the assembly properties of five EmN variants reveals that del95-99 and Q133H impact filament assembly capacities. In cells, these variants are located at the nuclear envelope, but the corresponding quantities of emerin-emerin and emerin-lamin proximities are decreased compared to wild-type protein. Furthermore, variant P183H favors EmN aggregation in vitro, and variant P183T provokes emerin accumulation in cytoplasmic foci in cells. Substitution of residue Pro183 might systematically favor oligomerization, leading to emerin aggregation and mislocalization in cells. Our results suggest that emerin self-assembly is necessary for its proper function and that a loss of either the protein itself or its ability to self-assemble causes muscular dystrophy.

  2. Properties of colloidal corrosion products and their effects on nuclear plants: Final report

    SciTech Connect

    Matijevic, E.

    1986-12-01

    A number of different solid particles found in nuclear reactor coolant have been produced in the laboratory. Such particles result from corrosion processes at metal piping and component surfaces. The particles produced and studied in this work differ from those observed in power plant water in two respects: (1) they are all of one narrowly controlled particle diameter and particle shape; (2) they are all of one simple composition - such as magnetite or hematite. The methods for making new supplies of these particles are provided for use by those wishing to study, for example, how best to dissolve surface oxides during a decontamination of plant piping surfaces. The model oxides aid in sorting out the proper dissolution procedures by providing a well-defined simulation of each separate constituent of plant surfaces in a form where dissolution rates are easily measured. Measurements of the properties of magnetite, hematite, and nickel-iron-cobalt ferrites relevant to radioactive cobalt-60 transport have been made and are reported in summary form. Some of these properties studied are (1) cobalt adsorption as a function of temperature and pH; (2) magnetic properties to assess the ease of magnetic filtration; (3) dissolution rates by the commonly employed decontamination chemicals. Copies of 41 separate scientific journal publications resulting from this work are reproduced in microfiche in the back cover pocket.

  3. The optimization of mechanical properties for nuclear transportation casks in ASTM A350 LF5

    SciTech Connect

    Price, S.; Honeyman, G.A.

    1997-12-31

    Transport flasks are required for the movement of spent nuclear fuel. Due to their nature of operation, it is necessary that these flasks are produced from forged steels with exceptional toughness properties. The material specification generally cited for flask manufacture is ASTM A350 Grade LF5 Class 1, a carbon-manganese-nickel alloy. The range of chemical analysis permitted by this specification is very broad and it is the responsibility of the material manufacturer to select a composition within this range which will satisfy all the mechanical properties requirements, and to ensure safe and reliable performance. Forgemasters Steel and Engineering Limited have experience in the manufacture of large high integrity fuel element flask forgings which extend over several decades. This experience and involvement in international standards in US, Europe and Japan has facilitated the development of an optimized analysis with a low carbon content, nickel levels towards the top end of the allowed range, a deliberate aluminum addition to control grain size and strictly controlled residual element levels. The resultant steel has excellent low temperature impact properties which greatly exceed the requirements of the specification. This analysis is now being adopted for the manufacture of all current transport flasks.

  4. Modeling of Some Physical Properties of Zirconium Alloys for Nuclear Applications in Support of UFD Campaign

    SciTech Connect

    Michael V. Glazoff

    2013-08-01

    Zirconium-based alloys Zircaloy-2 and Zircaloy-4 are widely used in the nuclear industry as cladding materials for light water reactor (LWR) fuels. These materials display a very good combination of properties such as low neutron absorption, creep behavior, stress-corrosion cracking resistance, reduced hydrogen uptake, corrosion and/or oxidation, especially in the case of Zircaloy-4. However, over the last couple of years, in the post-Fukushima Daiichi world, energetic efforts have been undertaken to improve fuel clad oxidation resistance during off-normal temperature excursions. Efforts have also been made to improve upon the already achieved levels of mechanical behavior and reduce hydrogen uptake. In order to facilitate the development of such novel materials, it is very important to achieve not only engineering control, but also a scientific understanding of the underlying material degradation mechanisms, both in working conditions and in storage of used nuclear fuel. This report strives to contribute to these efforts by constructing the thermodynamic models of both alloys; constructing of the respective phase diagrams, and oxidation mechanisms. A special emphasis was placed upon the role of zirconium suboxides in hydrogen uptake reduction and the atomic mechanisms of oxidation. To that end, computational thermodynamics calculations were conducted concurrently with first-principles atomistic modeling.

  5. KPNA7, a nuclear transport receptor, promotes malignant properties of pancreatic cancer cells in vitro

    SciTech Connect

    Laurila, Eeva; Vuorinen, Elisa; Savinainen, Kimmo; Rauhala, Hanna; Kallioniemi, Anne

    2014-03-10

    Pancreatic cancer is an aggressive malignancy and one of the leading causes of cancer deaths. The high mortality rate is mostly due to the lack of appropriate tools for early detection of the disease and a shortage of effective therapies. We have previously shown that karyopherin alpha 7 (KPNA7), the newest member of the alpha karyopherin family of nuclear import receptors, is frequently amplified and overexpressed in pancreatic cancer. Here, we report that KPNA7 expression is absent in practically all normal human adult tissues but elevated in several pancreatic cancer cell lines. Inhibition of KPNA7 expression in AsPC-1 and Hs700T pancreatic cancer cells led to a reduction in cell growth and decreased anchorage independent growth, as well as increased autophagy. The cell growth effects were accompanied by an induction of the cell cycle regulator p21 and a G1 arrest of the cell cycle. Interestingly, the p21 induction was caused by increased mRNA synthesis and not defective nuclear transport. These data strongly demonstrate that KPNA7 silencing inhibits the malignant properties of pancreatic cancer cells in vitro and thereby provide the first evidence on the functional role for KPNA7 in human cancer. - Highlights: • KPNA7 expression is elevated in several pancreatic cancer cell lines. • KPNA7 silencing in high expressing cancer cells leads to growth inhibition. • The cell growth reduction is associated with p21 induction and G1 arrest. • KPNA7 silencing is also accompanied with increased autophagy.

  6. Oscillator strengths, first-order properties, and nuclear gradients for local ADC(2)

    SciTech Connect

    Schütz, Martin

    2015-06-07

    We describe theory and implementation of oscillator strengths, orbital-relaxed first-order properties, and nuclear gradients for the local algebraic diagrammatic construction scheme through second order. The formalism is derived via time-dependent linear response theory based on a second-order unitary coupled cluster model. The implementation presented here is a modification of our previously developed algorithms for Laplace transform based local time-dependent coupled cluster linear response (CC2LR); the local approximations thus are state specific and adaptive. The symmetry of the Jacobian leads to considerable simplifications relative to the local CC2LR method; as a result, a gradient evaluation is about four times less expensive. Test calculations show that in geometry optimizations, usually very similar geometries are obtained as with the local CC2LR method (provided that a second-order method is applicable). As an exemplary application, we performed geometry optimizations on the low-lying singlet states of chlorophyllide a.

  7. Oscillator strengths, first-order properties, and nuclear gradients for local ADC(2)

    NASA Astrophysics Data System (ADS)

    Schütz, Martin

    2015-06-01

    We describe theory and implementation of oscillator strengths, orbital-relaxed first-order properties, and nuclear gradients for the local algebraic diagrammatic construction scheme through second order. The formalism is derived via time-dependent linear response theory based on a second-order unitary coupled cluster model. The implementation presented here is a modification of our previously developed algorithms for Laplace transform based local time-dependent coupled cluster linear response (CC2LR); the local approximations thus are state specific and adaptive. The symmetry of the Jacobian leads to considerable simplifications relative to the local CC2LR method; as a result, a gradient evaluation is about four times less expensive. Test calculations show that in geometry optimizations, usually very similar geometries are obtained as with the local CC2LR method (provided that a second-order method is applicable). As an exemplary application, we performed geometry optimizations on the low-lying singlet states of chlorophyllide a.

  8. Heavy-flavor production and medium properties in high-energy nuclear collisions --What next?

    DOE PAGES

    Aarts, G.; Aichelin, J.; Allton, C.; ...

    2017-05-16

    Open and hidden heavy-flavor physics in high-energy nuclear collisions are entering a new and exciting stage towards reaching a clearer understanding of the new experimental results with the possibility to link them directly to the advancement in lattice Quantum Chromo-Dynamics (QCD). Some recent results from experiments and theoretical developments regarding open and hidden heavy-flavor dynamics have been debated at the Lorentz Workshop Tomography of the Quark-Gluon Plasma with Heavy Quarks, which was held in October 2016 in Leiden, The Netherlands. Here, we summarize identified common understandings and developed strategies for the upcoming five years, which aim at achieving a profoundmore » knowledge of the dynamical properties of the quark-gluon plasma.« less

  9. Temperature and momentum dependence of single-particle properties in hot asymmetric nuclear matter

    SciTech Connect

    Moustakidis, Ch. C.

    2008-11-15

    We have studied the effects of momentum-dependent interactions on the single-particle properties of hot asymmetric nuclear matter. In particular, the single-particle potential of protons and neutrons as well as the symmetry potential have been studied within a self-consistent model using a momentum-dependent effective interaction. In addition, the isospin splitting of the effective mass has been derived from the above model. In each case temperature effects have been included and analyzed. The role of the specific parametrization of the effective interaction used in the present work has been investigated. It has been concluded that the behavior of the symmetry potential depends strongly on the parametrization of the interaction part of the energy density and the momentum dependence of the regulator function. The effects of the parametrization have been found to be less pronounced on the isospin mass splitting.

  10. Heavy-flavor production and medium properties in high-energy nuclear collisions -What next?

    NASA Astrophysics Data System (ADS)

    Aarts, G.; Aichelin, J.; Allton, C.; Arnaldi, R.; Bass, S. A.; Bedda, C.; Brambilla, N.; Bratkovskaya, E.; Braun-Munzinger, P.; Bruno, G. E.; Dahms, T.; Das, S. K.; Dembinski, H.; Djordjevic, M.; Ferreiro, E.; Frawley, A.; Gossiaux, P.-B.; Granier de Cassagnac, R.; Grelli, A.; He, M.; Horowitz, W. A.; Innocenti, G. M.; Jo, M.; Kaczmarek, O.; Kuijer, P. G.; Laine, M.; Lombardo, M. P.; Mischke, A.; Munhoz, M. G.; Nahrgang, M.; Nguyen, M.; Oliveira da Silva, A. C.; Petreczky, P.; Rothkopf, A.; Schmelling, M.; Scomparin, E.; Song, T.; Stachel, J.; Suaide, A. A. P.; Tolos, L.; Trzeciak, B.; Uras, A.; van Doremalen, L.; Vermunt, L.; Vigolo, S.; Xu, N.; Ye, Z.; Zanoli, H. J. C.; Zhuang, P.

    2017-05-01

    Open and hidden heavy-flavor physics in high-energy nuclear collisions are entering a new and exciting stage towards reaching a clearer understanding of the new experimental results with the possibility to link them directly to the advancement in lattice Quantum Chromo-Dynamics (QCD). Recent results from experiments and theoretical developments regarding open and hidden heavy-flavor dynamics have been debated at the Lorentz Workshop Tomography of the Quark-Gluon Plasma with Heavy Quarks, which was held in October 2016 in Leiden, The Netherlands. In this contribution, we summarize identified common understandings and developed strategies for the upcoming five years, which aim at achieving a profound knowledge of the dynamical properties of the quark-gluon plasma.

  11. Properties of colloidal corrosion products and their effects on nuclear plants. Volume 1. Executive summary. Final report. [PWR; BWR

    SciTech Connect

    Matijevic, E.

    1982-10-01

    The properties of aqueous dispersions of finely divided oxides of iron, nickel, cobalt, chromium, and copper are described in overview fashion. More detailed aspects of this work will be found in a separate, larger report, NP-2606, Volume 2. The properties of these oxide corrosion products of importance to nuclear reactor water system technology are emphasized: adhesion, desorption, dissolution, transformation, and adsorption of dissolved species such as Co/sup 60/ ions. The work is fundamental to many LWR problems - radiation transport to piping surfaces, avoidance of crud buildup on nuclear fuel rods, decontamination and chemical cleaning of heat exchangers, and control of corrosion of piping.

  12. Characterizing petrophysical properties of carbonate rocks using nuclear magnetic resonance and spectral induced polarization

    NASA Astrophysics Data System (ADS)

    Zhang, Fan; Zhang, Chi; Rankey, Eugene

    2016-04-01

    Unlike sandstones, with well-characterized correlations between porosity and permeability, carbonate rocks are well known for their highly complex petrophysical behaviors due to their intrinsically heterogeneous pore shape, pore size, and pore distributions and connectivity. The characterization of petrophysical properties of carbonate rocks, including rock properties and rock-fluid interactions, remains big challenges. This laboratory study focuses on integrating two geophysical methods: nuclear magnetic resonance (NMR) and spectral induced polarization (SIP) to determine porosity, pore size distribution, and permeability of carbonate rocks. NMR measures the relaxation of hydrogen nuclei at pore scale. Samples with different pore structures saturated by fluids have molecular relaxation responses to the external magnetic field which could generate various NMR signals. Permeability estimation from NMR in siliciclastic rocks is routine, however, is problematic in carbonates. SIP determines complex resistivity of a sample across a wide range of frequency and is sensitive to variations in the properties of solid-fluid and fluid-fluid interfaces in porous media. Previous studies investigated the relationships between permeability and parameters derived from SIP data, but are restricted to narrow lithology range. Our study used carbonate core samples from three depositional environments: tidal zone, shallow marine, and platform/reef margin of an atoll. Samples were fully saturated by water for T2 relaxation measurements and complex conductivity measurements at low frequencies. We compare the pore volume to surface area ratio measured from NMR and SIP and assess the applicability of established petrophysical models to estimate permeability from NMR and SIP data. We hope to build a relationship between NMR signals, SIP responses and petrophysical properties in carbonate rocks. The results could also provide new data and help further understand the unique and complex pore

  13. A review: applications of the phase field method in predicting microstructure and property evolution of irradiated nuclear materials

    DOE PAGES

    Li, Yulan; Hu, Shenyang; Sun, Xin; ...

    2017-04-14

    Here, complex microstructure changes occur in nuclear fuel and structural materials due to the extreme environments of intense irradiation and high temperature. This paper evaluates the role of the phase field method in predicting the microstructure evolution of irradiated nuclear materials and the impact on their mechanical, thermal, and magnetic properties. The paper starts with an overview of the important physical mechanisms of defect evolution and the significant gaps in simulating microstructure evolution in irradiated nuclear materials. Then, the phase field method is introduced as a powerful and predictive tool and its applications to microstructure and property evolution in irradiatedmore » nuclear materials are reviewed. The review shows that (1) Phase field models can correctly describe important phenomena such as spatial-dependent generation, migration, and recombination of defects, radiation-induced dissolution, the Soret effect, strong interfacial energy anisotropy, and elastic interaction; (2) The phase field method can qualitatively and quantitatively simulate two-dimensional and three-dimensional microstructure evolution, including radiation-induced segregation, second phase nucleation, void migration, void and gas bubble superlattice formation, interstitial loop evolution, hydrate formation, and grain growth, and (3) The Phase field method correctly predicts the relationships between microstructures and properties. The final section is dedicated to a discussion of the strengths and limitations of the phase field method, as applied to irradiation effects in nuclear materials.« less

  14. A review: applications of the phase field method in predicting microstructure and property evolution of irradiated nuclear materials

    NASA Astrophysics Data System (ADS)

    Li, Yulan; Hu, Shenyang; Sun, Xin; Stan, Marius

    2017-04-01

    Complex microstructure changes occur in nuclear fuel and structural materials due to the extreme environments of intense irradiation and high temperature. This paper evaluates the role of the phase field method in predicting the microstructure evolution of irradiated nuclear materials and the impact on their mechanical, thermal, and magnetic properties. The paper starts with an overview of the important physical mechanisms of defect evolution and the significant gaps in simulating microstructure evolution in irradiated nuclear materials. Then, the phase field method is introduced as a powerful and predictive tool and its applications to microstructure and property evolution in irradiated nuclear materials are reviewed. The review shows that (1) Phase field models can correctly describe important phenomena such as spatial-dependent generation, migration, and recombination of defects, radiation-induced dissolution, the Soret effect, strong interfacial energy anisotropy, and elastic interaction; (2) The phase field method can qualitatively and quantitatively simulate two-dimensional and three-dimensional microstructure evolution, including radiation-induced segregation, second phase nucleation, void migration, void and gas bubble superlattice formation, interstitial loop evolution, hydrate formation, and grain growth, and (3) The Phase field method correctly predicts the relationships between microstructures and properties. The final section is dedicated to a discussion of the strengths and limitations of the phase field method, as applied to irradiation effects in nuclear materials.

  15. Glass Property Models, Constraints, and Formulation Approaches for Vitrification of High-Level Nuclear Wastes at the US Hanford Site

    SciTech Connect

    Kim, Dong-Sang

    2015-03-02

    The legacy nuclear wastes stored in underground tanks at the US Department of Energy’s Hanford site is planned to be separated into high-level waste and low-activity waste fractions and vitrified separately. Formulating optimized glass compositions that maximize the waste loading in glass is critical for successful and economical treatment and immobilization of nuclear wastes. Glass property-composition models have been developed and applied to formulate glass compositions for various objectives for the past several decades. The property models with associated uncertainties and combined with composition and property constraints have been used to develop preliminary glass formulation algorithms designed for vitrification process control and waste form qualification at the planned waste vitrification plant. This paper provides an overview of current status of glass property-composition models, constraints applicable to Hanford waste vitrification, and glass formulation approaches that have been developed for vitrification of hazardous and highly radioactive wastes stored at the Hanford site.

  16. Two lanthanide-hydroxo clusters with different nuclearity: Synthesis, structures, luminescent and magnetic properties

    NASA Astrophysics Data System (ADS)

    Li, Xi-Li; Zhu, Cancan; Zhang, Xue-Li; Hu, Ming; Wang, Ai-Ling; Xiao, Hong-Ping

    2017-01-01

    Under the identical reaction conditions, two new TbIII and SmIII-hydroxo clusters with different nuclearity have been prepared and characterized by X-ray crystallography, spectroscopic methods and magnetic measurements. Solid-state structure analyses reveal that the TbIII cluster shows a pentanuclear square pyramidal shape of the composition [Tb5(μ3-OH)4(μ4-OH)(dbm)10]·2H2O (1, dbm- = dibenzoylmethanate) with the dbm ligands presenting two types of coordination modes [η2-and (μ-O)-η2-]. The SmIII species presents a tetranuclear parallelogram structure formulated as [Sm4(μ3-OH)2(dbm)10]·12H2O (2), and three types of coordination modes [η2-, (μ-O)-η2- and (μ-O)2-η2-] for dbm ligands are observed. The measurements of magnetic properties indicate that the direct-current (dc) magnetic behaviors of two clusters mainly result from the thermal depopulation of the Stark sublevels of the TbIII and SmIII ions, respectively. Meanwhile, alternating current (ac) magnetic susceptibility of 1 is also assessed. Investigations on luminescence properties show that 2 displays characteristic emission of the SmIII ion in visible range, while 1 does not exhibit any detectable emission. The interpretations of different emission behaviors for 1 and 2 are also presented in detail.

  17. Asymmetric nuclear matter and neutron star properties within the extended Brueckner theory

    NASA Astrophysics Data System (ADS)

    Hassaneen, Khaled S. A.

    2017-01-01

    Microscopically, the equation of state (EOS) and other properties of asymmetric nuclear matter at zero temperature have been investigated extensively by adopting the non-relativistic Brueckner-Hartree-Fock (BHF) and the extended BHF approaches by using the self-consistent Green's function approach or by including a phenomenological three-body force. Once three-body forces are introduced, the phenomenological saturation point is reproduced and the theory is applied to the study of neutron star properties. We can calculate the total mass and radius for neutron stars using various equations of state at high densities in β-equilibrium without hyperons. A comparison with other microscopic predictions based on non-relativistic and density-dependent relativistic mean-field calculations has been done. It is found that relativistic EOS yields however larger mass and radius for neutron star than predictions based on non-relativistic approaches. Also the three-body force plays a crucial role to deduce the theoretical value of the maximum mass of neutron stars in agreement with recent measurements of the neutron star mass.

  18. Nuclear matter properties in the relativistic mean-field theory at finite temperature with interaction between sigma-omega mesons

    SciTech Connect

    Costa, R. S.; Duarte, S. B.; Oliveira, J. C. T.; Chiapparini, M.

    2010-05-21

    We study the nuclear matter properties in the regime of high temperatures using a relativistic mean-field theory. Contrasting with the usual linear Walecka model, we include the sigma-omega meson coupling in order to investigate the role of this interaction in the nucleon effective mass behavior. Some numerical results are presented and discussed.

  19. 10 CFR 770.5 - How does DOE notify persons and entities that defense nuclear facility real property is available...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false How does DOE notify persons and entities that defense... Energy DEPARTMENT OF ENERGY TRANSFER OF REAL PROPERTY AT DEFENSE NUCLEAR FACILITIES FOR ECONOMIC... available for transfer for economic development? (a) Field Office Managers annually make available to...

  20. Distinctive Properties of the Nuclear Localization Signals of Inner Nuclear Membrane Proteins Heh1 and Heh2

    SciTech Connect

    Lokareddy, Ravi K.; Hapsari, Rizqiya A.; van Rheenen, Mathilde; Pumroy, Ruth A.; Bhardwaj, Anshul; Steen, Anton; Veenhoff, Liesbeth M.; Cingolani, Gino

    2015-06-04

    Targeting of ER-synthesized membrane proteins to the inner nuclear membrane (INM) has long been explained by the diffusion-retention model. However, several INM proteins contain non-classical nuclear localization signal (NLS) sequences, which, in a few instances, have been shown to promote importin α/β- and Ran-dependent translocation to the INM. Here, using structural and biochemical methods, we show that yeast INM proteins Heh2 and Src1/Heh1 contain bipartite import sequences that associate intimately with the minor NLS-binding pocket of yeast importin α and unlike classical NLSs efficiently displace the IBB domain in the absence of importin β. In vivo, the intimate interactions at the minor NLS-binding pocket make the h2NLS highly efficient at recruiting importin α at the ER and drive INM localization of endogenous Heh2. Thus, h1/h2NLSs delineate a novel class of super-potent, IBB-like membrane protein NLSs, distinct from classical NLSs found in soluble cargos and of general interest in biology.

  1. Distinctive Properties of the Nuclear Localization Signals of Inner Nuclear Membrane Proteins Heh1 and Heh2.

    PubMed

    Lokareddy, Ravi K; Hapsari, Rizqiya A; van Rheenen, Mathilde; Pumroy, Ruth A; Bhardwaj, Anshul; Steen, Anton; Veenhoff, Liesbeth M; Cingolani, Gino

    2015-07-07

    Targeting of ER-synthesized membrane proteins to the inner nuclear membrane (INM) has long been explained by the diffusion-retention model. However, several INM proteins contain non-classical nuclear localization signal (NLS) sequences, which, in a few instances, have been shown to promote importin α/β- and Ran-dependent translocation to the INM. Here, using structural and biochemical methods, we show that yeast INM proteins Heh2 and Src1/Heh1 contain bipartite import sequences that associate intimately with the minor NLS-binding pocket of yeast importin α and unlike classical NLSs efficiently displace the IBB domain in the absence of importin β. In vivo, the intimate interactions at the minor NLS-binding pocket make the h2NLS highly efficient at recruiting importin α at the ER and drive INM localization of endogenous Heh2. Thus, h1/h2NLSs delineate a novel class of super-potent, IBB-like membrane protein NLSs, distinct from classical NLSs found in soluble cargos and of general interest in biology. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Black Hole Demographics in and Nuclear Properties of Nearby Low Luminosity Radio Galaxies; Connections to Radio Activity?

    NASA Technical Reports Server (NTRS)

    Baum, S. A.; Kleijn, G. A. Verdoes; Xu, C.; ODea, C. P.; deZeeuw, P. T.

    2004-01-01

    We combine the results of an HST STIS and WFPC study of a complete sample of 21 nearby UGC low luminosity radio galaxies with the results of a radio VLA and VLBA study of the same sample. We examine the relationship between the stellar and gaseous properties of the galaxies on tens to hundreds of parsec scale with the properties of the radio jets on the same scale. From the VLA and VLBA data we constrain the physics of the outflowing radio plasma from the tens of parsecs to hundreds of kiloparsec scales. From the WFPC2 H alpha and dust images and the STIS kinematics of the near nuclear gas we obtain constraints on the orientation of near nuclear disks of gas and measures of the nuclear stellar, continuum point source, and line emission fluxes. Under the statistically supported assumption that the radio jet issues perpendicular to the disk, we use the orientation of the optical (large scale accretion?) disks to constrain the three-dimensional orientation of the radio ejection. From HST/STIS spectroscopy of the near-nuclear emission line gas we obtain measures/limits on the black hole masses. We examine correlations between the VLBA and VLA-scale radio emission, the nuclear line emission, and the nuclear optical and radio continuum emission. Though our sample is relatively small, it is uniquely well defined, spans a narrow range in redshift and we have a consistent set of high resolution data with which to carefully examine these relationships. We use the combined radio and optical data to: 1) Constrain the orientation, physics, and bulk outflow speed of the radio plasma; 2) Put limits on the mass accretion rate and study the relationship between black hole mass, radio luminosity, and near nuclear gaseous content; 3) Provide insight into the relationship between BL Lac objects and low luminosity radio galaxies.

  3. Analytic nuclear forces and molecular properties from full configuration interaction quantum Monte Carlo

    NASA Astrophysics Data System (ADS)

    Thomas, Robert E.; Opalka, Daniel; Overy, Catherine; Knowles, Peter J.; Alavi, Ali; Booth, George H.

    2015-08-01

    Unbiased stochastic sampling of the one- and two-body reduced density matrices is achieved in full configuration interaction quantum Monte Carlo with the introduction of a second, "replica" ensemble of walkers, whose population evolves in imaginary time independently from the first and which entails only modest additional computational overheads. The matrices obtained from this approach are shown to be representative of full configuration-interaction quality and hence provide a realistic opportunity to achieve high-quality results for a range of properties whose operators do not necessarily commute with the Hamiltonian. A density-matrix formulated quasi-variational energy estimator having been already proposed and investigated, the present work extends the scope of the theory to take in studies of analytic nuclear forces, molecular dipole moments, and polarisabilities, with extensive comparison to exact results where possible. These new results confirm the suitability of the sampling technique and, where sufficiently large basis sets are available, achieve close agreement with experimental values, expanding the scope of the method to new areas of investigation.

  4. Molecular properties in the Tamm-Dancoff approximation: indirect nuclear spin-spin coupling constants

    NASA Astrophysics Data System (ADS)

    Cheng, Chi Y.; Ryley, Matthew S.; Peach, Michael J. G.; Tozer, David J.; Helgaker, Trygve; Teale, Andrew M.

    2015-07-01

    The Tamm-Dancoff approximation (TDA) can be applied to the computation of excitation energies using time-dependent Hartree-Fock (TD-HF) and time-dependent density-functional theory (TD-DFT). In addition to simplifying the resulting response equations, the TDA has been shown to significantly improve the calculation of triplet excitation energies in these theories, largely overcoming issues associated with triplet instabilities of the underlying reference wave functions. Here, we examine the application of the TDA to the calculation of another response property involving triplet perturbations, namely the indirect nuclear spin-spin coupling constant. Particular attention is paid to the accuracy of the triplet spin-dipole and Fermi-contact components. The application of the TDA in HF calculations leads to vastly improved results. For DFT calculations, the TDA delivers improved stability with respect to geometrical variations but does not deliver higher accuracy close to equilibrium geometries. These observations are rationalised in terms of the ground- and excited-state potential energy surfaces and, in particular, the severity of the triplet instabilities associated with each method. A notable feature of the DFT results within the TDA is their similarity across a wide range of different functionals. The uniformity of the TDA results suggests that some conventional evaluations may exploit error cancellations between approximations in the functional forms and those arising from triplet instabilities. The importance of an accurate treatment of correlation for evaluating spin-spin coupling constants is highlighted by this comparison.

  5. Nuclear resonant inelastic x-ray scattering: Methodology and extraction of vibrational properties of minerals

    NASA Astrophysics Data System (ADS)

    Hu, M. Y.; Alp, E. E.; Bi, W.; Sturhahn, W.; Toellner, T. S.; Zhao, J.

    2013-12-01

    Nuclear resonant inelastic x-ray scattering (NRIXS) is a synchrotron radiation based experimental method [1]. Since its introduction almost 20 years ago [2], NRIXS has found an expanding range of applications of studying lattice dynamics in condensed matter physics, materials science, high-pressure research, geosciences, and biophysics. After the first high pressure application in geophysics of measuring sound velocity of iron up to 153 GPa [3], it has become a widely used method to investigate deep earth compositions through sound velocity measurements [4,5]. Thermodynamic properties are also explored, in particular Grueneisen parameters [6]. Later, it was realized that isotope fractionaton factors can be derived from NRIXS measurements [7,8]. Sum rules and moments of NRIXS is a critical part of this methodology [9,10]. We will discuss this and in general the data analysis of NRIXS which enables the above mentioned applications. [1] Alp et al. Hyperfine Interactions 144/145, 3 (2002) [2] Sturhahn et al., PRL 74, 3832 (1995) [3] Mao et al., Science 292, 914 (2001) [4] Hu et al., PRB 67, 094304 (2003) [5] Sturhahn & Jackson, GSA special paper 421 (2007) [6] Murphy et al., Geophys. Res. Lett. 38, L24306 (2011) [7] Polyakov, Science 323, 912 (2009) [8] Dauphas et al., Geochimica et Cosmochimica Acta 94, 254 (2012) [9] Lipkin, PRB 52, 10073 (1995) [10] Hu et al., PRB 87, 064301 (2013)

  6. Analytic nuclear forces and molecular properties from full configuration interaction quantum Monte Carlo

    SciTech Connect

    Thomas, Robert E.; Overy, Catherine; Opalka, Daniel; Alavi, Ali; Knowles, Peter J.; Booth, George H.

    2015-08-07

    Unbiased stochastic sampling of the one- and two-body reduced density matrices is achieved in full configuration interaction quantum Monte Carlo with the introduction of a second, “replica” ensemble of walkers, whose population evolves in imaginary time independently from the first and which entails only modest additional computational overheads. The matrices obtained from this approach are shown to be representative of full configuration-interaction quality and hence provide a realistic opportunity to achieve high-quality results for a range of properties whose operators do not necessarily commute with the Hamiltonian. A density-matrix formulated quasi-variational energy estimator having been already proposed and investigated, the present work extends the scope of the theory to take in studies of analytic nuclear forces, molecular dipole moments, and polarisabilities, with extensive comparison to exact results where possible. These new results confirm the suitability of the sampling technique and, where sufficiently large basis sets are available, achieve close agreement with experimental values, expanding the scope of the method to new areas of investigation.

  7. Electronic properties of Cs-intercalated single-walled carbon nanotubes derived from nuclear magnetic resonance

    NASA Astrophysics Data System (ADS)

    Abou-Hamad, E.; Goze-Bac, C.; Nitze, F.; Schmid, M.; Aznar, R.; Mehring, M.; Wågberg, T.

    2011-05-01

    We report on the electronic properties of Cs-intercalated single-walled carbon nanotubes (SWNTs). A detailed analysis of the 13C and 133Cs nuclear magnetic resonance (NMR) spectra reveals an increased metallization of the pristine SWNTs under Cs intercalation. The 'metallization' of CsxC materials where x=0-0.144 is evidenced from the increased local electronic density of states (DOS) n(EF) at the Fermi level of the SWNTs as determined from spin-lattice relaxation measurements. In particular, there are two distinct electronic phases called α and β and the transition between these occurs around x=0.05. The electronic DOS at the Fermi level increases monotonically at low intercalation levels x<0.05 (α-phase), whereas it reaches a plateau in the range 0.05<=x<=0.143 at high intercalation levels (β-phase). The new β-phase is accompanied by a hybridization of Cs(6s) orbitals with C(sp2) orbitals of the SWNTs. In both phases, two types of metallic nanotubes are found with a low and a high local n(EF), corresponding to different local electronic band structures of the SWNTs.

  8. Nuclear magnetic resonance relaxation and diffusion measurements as a proxy for soil properties

    NASA Astrophysics Data System (ADS)

    Duschl, Markus; Pohlmeier, Andreas; Galvosas, Petrik; Vereecken, Harry

    2013-04-01

    Nuclear Magnetic Resonance (NMR) relaxation and NMR diffusion measurements are two of a series of fast and non-invasive NMR applications widely used e.g. as well logging tools in petroleum exploration [1]. For experiments with water, NMR relaxation measures the relaxation behaviour of former excited water molecules, and NMR diffusion evaluates the self-diffusion of water. Applied in porous media, both relaxation and diffusion measurements depend on intrinsic properties of the media like pore size distribution, connectivity and tortuosity of the pores, and water saturation [2, 3]. Thus, NMR can be used to characterise the pore space of porous media not only in consolidated sediments but also in soil. The physical principle behind is the relaxation of water molecules in an external magnetic field after excitation. In porous media water molecules in a surface layer of the pores relax faster than the molecules in bulk water because of interactions with the pore wall. Thus, the relaxation in smaller pores is generally faster than in bigger pores resulting in a relaxation time distribution for porous media with a range of pore sizes like soil [4]. In NMR diffusion experiments, there is an additional encoding of water molecules by application of a magnetic field gradient. Subsequent storage of the magnetization and decoding enables the determination of the mean square displacement and therefore of the self-diffusion of the water molecules [5]. Employing various relaxation and diffusion experiments, we get a measure of the surface to volume ratio of the pores and the tortuosity of the media. In this work, we show the characterisation of a set of sand and soil samples covering a wide range of textural classes by NMR methods. Relaxation times were monitored by the Carr-Purcell-Meiboom-Gill sequence and analysed using inverse Laplace transformation. Apparent self-diffusion constants were detected by a 13-intervall pulse sequence and variation of the storage time. We

  9. Description of induced nuclear fission with Skyrme energy functionals: Static potential energy surfaces and fission fragment properties

    NASA Astrophysics Data System (ADS)

    Schunck, N.; Duke, D.; Carr, H.; Knoll, A.

    2014-11-01

    Eighty years after its experimental discovery, a description of induced nuclear fission based solely on the interactions between neutrons and protons and quantum many-body methods still poses formidable challenges. The goal of this paper is to contribute to the development of a predictive microscopic framework for the accurate calculation of static properties of fission fragments for hot fission and thermal or slow neutrons. To this end, we focus on the 239Pu(n ,f ) reaction and employ nuclear density functional theory with Skyrme energy densities. Potential energy surfaces are computed at the Hartree-Fock-Bogoliubov approximation with up to five collective variables. We find that the triaxial degree of freedom plays an important role, both near the fission barrier and at scission. The impact of the parametrization of the Skyrme energy density and the role of pairing correlations on deformation properties from the ground state up to scission are also quantified. We introduce a general template for the quantitative description of fission fragment properties. It is based on the careful analysis of scission configurations, using both advanced topological methods and recently proposed quantum many-body techniques. We conclude that an accurate prediction of fission fragment properties at low incident neutron energies, although technologically demanding, should be within the reach of current nuclear density functional theory.

  10. Review of fracture properties of nuclear materials determined by Hertzian indentation

    SciTech Connect

    Routbort, J.; Matzke, H.

    1985-01-01

    A brief description of the determination of the surface fracture energy and the fracture toughness from a Hertzian indentation test is given. A number of theoretical and experimental problems are discussed. Results obtained on a variety of nuclear fuels and nuclear-waste-containment materials are reviewed and compared with values measured by other techniques. The Hertzian indentation test yields reliable fracture parameters.

  11. Characterization of Mechanical Properties of Nuclear Graphite Using Subsize Specimens and Reusing Tested Specimens

    SciTech Connect

    Ji Hyun, Yoon; Byun, Thak Sang; Strizak, Joe P; Snead, Lance Lewis

    2011-01-01

    The mechanical properties of NBG-18 nuclear grade graphite have been characterized using small specimen test techniques and statistical treatment on the test results. New fracture strength and toughness test techniques were developed to use subsize cylindrical specimens with glued heads and to reuse their broken halves. Three sets of subsize cylindrical specimens with the different diameters of 4 mm, 8 mm, and 12 mm were tested to obtain tensile fracture strength. The longer piece of the broken halves was cracked from side surfaces and tested under three-point bend loading to obtain fracture toughness. Both the strength and fracture toughness data were analyzed using Weibull distribution models focusing on size effect. The mean fracture strength decreased from 22.9 MPa to 21.5 MPa as the diameter increased from 4 mm to 12 mm, and the mean strength of 15.9 mm diameter standard specimen, 20.9 MPa, was on the extended trend line. These fracture strength data indicate that in the given diameter range the size effect is not significant and much smaller than that predicted by the Weibull statistics-based model. Further, no noticeable size effect existed in the fracture toughness data, whose mean values were in a narrow range of 1.21 1.26 MPa. The Weibull moduli measured for fracture strength and fracture toughness datasets were around 10. It is therefore believed that the small or negligible size effect enables to use the subsize specimens and that the new fracture toughness test method to reuse the broken specimens to help minimize irradiation space and radioactive waste.

  12. Nuclear structure properties and stellar weak rates for 76Se: Unblocking of the Gamow Teller strength

    NASA Astrophysics Data System (ADS)

    Nabi, Jameel-Un; Ishfaq, Mavra; Böyükata, Mahmut; Riaz, Muhammad

    2017-10-01

    At finite temperatures (≥ 107K), 76Se is abundant in the core of massive stars and electron capture on 76Se has a consequential role to play in the dynamics of core-collapse. The present work may be classified into two main categories. In the first phase we study the nuclear structure properties of 76Se using the interacting boson model-1 (IBM-1). The IBM-1 investigations include the energy levels, B (E 2) values and the prediction of the geometry. We performed the extended consistent-Q formalism (ECQF) calculation and later the triaxial formalism calculation (constructed by adding the cubic term to the ECQF). The geometry of 76Se can be envisioned within the formalism of the potential energy surface based on the classical limit of IBM-1 model. In the second phase, we reconfirm the unblocking of the Gamow-Teller (GT) strength in 76Se (a test case for nuclei having N > 40 and Z < 40). Using the deformed pn-QRPA model we calculate GT transitions, stellar electron capture cross section (within the limit of low momentum transfer) and stellar weak rates for 76Se. The distinguishing feature of our calculation is a state-by-state evaluation of stellar weak rates in a fully microscopic fashion. Results are compared with experimental data and previous calculations. The calculated GT distribution fulfills the Ikeda sum rule. Rates for β-delayed neutrons and emission probabilities are also calculated. Our study suggests that at high stellar temperatures and low densities, the β+-decay on 76Se should not be neglected and needs to be taken into consideration along with electron capture rates for simulation of presupernova evolution of massive stars.

  13. Smoke inputs to climate models: optical properties and height distribution for nuclear winter studies

    SciTech Connect

    Penner, J.E.; Haselman, L.C. Jr.

    1985-04-01

    Smoke from fires produced in the aftermath of a major nuclear exchange has been predicted to cause large decreases in land surface temperatures. The extent of the decrease and even the sign of the temperature change depend on the optical characteristics of the smoke and how it is distributed with altitude. The height distribution of smoke over a fire is determined by the amount of buoyant energy produced by the fire and the amount of energy released by the latent heat of condensation of water vapor. The optical properties of the smoke depend on the size distribution of smoke particles which changes due to coagulation within the lofted plume. We present calculations demonstrating these processes and estimate their importance for the smoke source term input for climate models. For high initial smoke densities and for absorbing smoke ( m = 1.75 - 0.3i), coagulation of smoke particles within the smoke plume is predicted to first increase, then decrease, the size-integrated extinction cross section. However, at the smoke densities predicted in our model (assuming a 3% emission rate for smoke) and for our assumed initial size distribution, the attachment rates for brownian and turbulent collision processes are not fast enough to alter the smoke size distribution enough to significantly change the integrated extinction cross section. Early-time coagulation is, however, fast enough to allow further coagulation, on longer time scales, to act to decrease the extinction cross section. On these longer time scales appropriate to climate models, coagulation can decrease the extinction cross section by almost a factor of two before the smoke becomes well mixed around the globe. This process has been neglected in past climate effect evaluations, but could have a significant effect, since the extinction cross section enters as an exponential factor in calculating the light attenuation due to smoke. 10 refs., 20 figs.

  14. Nuclear Halos

    SciTech Connect

    Vogt, Erich

    2010-07-27

    We show that extreme nuclear halos are caused only by pairs of s-wave neutrons (or single s-wave neutrons) and that such states occur much more frequently in the periodic table than previously believed. Besides lingering long near zero neutron separation energy such extreme halos have very remarkable properties: they can contribute significantly to the nuclear density at more than twice the normal nuclear radius and their spreading width can be very narrow. The properties of these states are primarily determined by the ''thickness'' of the nuclear surface in the mean-free nuclear potential and thus their importance increases greatly as we approach the neutron drip line. We discuss what such extreme halos are, where they occur, what their properties are and some of their impact on nuclear observations.

  15. Nuclear Pasta

    NASA Astrophysics Data System (ADS)

    da Silva Schneider, Andre; Horowitz, Charles; Berry, Don; Briggs, Christian

    2014-03-01

    For decades it has been theorized that just below nuclear saturation density matter undergoes a series of phase transitions. These phases, which are expected to exist in core-collapse supernovae and neutron stars, involve a range of exotic nuclear shapes collectively known as nuclear pasta. Recently, Jose Pons and collaborators suggested that ``the maximum period of isolated X-ray pulsars may be the first observational evidence for an amorphous inner crust, ..., possibly owing to the existence of a nuclear pasta phase.'' In this talk we present results of semi-classical molecular dynamics simulations of nuclear pasta and discuss how each phase might contribute to neutron star crust properties.

  16. The Alarmin Properties of DNA and DNA-associated Nuclear Proteins.

    PubMed

    Magna, Melinda; Pisetsky, David S

    2016-05-01

    The communication of cell injury and death is a critical element in host defense. Although immune cells can serve this function by elaborating cytokines and chemokines, somatic cells can repurpose nuclear macromolecules to function as damage-associated molecular patterns (DAMPs) or alarmins to exert similar activity. Among these molecules, DNA, high-mobility group box-1, and histone proteins can all act as DAMPs once they are in an extracellular location. This review describes current information on the role of the nuclear DAMPs, their translocation to the outside of cells, and pathways of activation after uptake into the inside of immune cells. MEDLINE and PubMed databases were searched for citations (1990-2016) in English related to the following terms: DAMPs, high-mobility group box-1, DNA, histones, cell death, danger, and immune activation. Selected articles with the most relevant studies were included for a more detailed consideration. Although nuclear molecules have important structural and genetic regulatory roles inside the cell nucleus, when released into the extracellular space during cell death, these molecules can acquire immune activity and serve as alarmins or DAMPs. Although apoptosis is generally considered the source of extracellular nuclear material, other cell death pathways such as necroptosis, NETosis, and pyroptosis can contribute to the release of nuclear molecules. Importantly, the release of nuclear DAMPs occurs with both soluble and particulate forms of these molecules. The activity of nuclear molecules may depend on posttranslational modifications, redox changes, and the binding of other molecules. Once in an extracellular location, nuclear DAMPs can engage the same pattern recognition receptors as do pathogen-associated molecular patterns. These interactions can activate immune cells and lead to cytokine and chemokine production. Among these receptors, internal receptors for DNA are key to the response to this molecule; the likely

  17. Nuclear magnetic resonance properties of marine sediments from the Nankai Trough

    NASA Astrophysics Data System (ADS)

    Thomas, B.; Daigle, H.

    2013-12-01

    We performed nuclear magnetic resonance (NMR) measurements of longitudinal (T1) and transverse (T2) relaxation times on samples from Integrated Ocean Drilling Program (IODP) Expedition 333 Sites C0011, C0012, and C0018. We compared these measurements with independent measurements of pore size distribution and permeability to develop methods for determining pore structure and permeability directly from NMR data. Geometric means of the T1 and T2 distributions ranged from 0.87 to 7.95 and 0.45 to 6.04 ms, respectively. We compared the T1 and T2 distributions to pore size distributions determined from Mercury Injection Capillary Pressure (MICP) measurements to determine the longitudinal and transverse surface relaxivities, which link relaxation time distribution to pore size. Longitudinal and transverse surface relaxivities ranged generally from 12.2 to 21.8 and 17.51 to 44.04 μm/s, respectively, with one outlier from the sediment-basement interface at Site C0012 having relaxivity values of 256.9 and 335.6 μm/s. Larger surface relaxivities were found to correlate with higher iron content in the sediments. The ratio of the geometric means of the relaxation time distributions (T1LM/T2LM) and the ratio of the surface relaxivities (ρ2/ρ1) both increase linearly with magnetic susceptibility, but magnetic susceptibility displays no relationship with the individual relaxation times or surface relaxivities. We additionally compared T2 values to measured permeabilities using the Schlumberger-Doll Research (SDR) equation. SDR equation coefficient A values were generally in the range of 7x10-18 to 8x10-17 m2/ms2 (0.007 to 0.080 mD/ms2). A is inversely correlated with clay-size particle fraction and specific surface, which suggests that A is mainly controlled by changes in pore or grain structure rather than mineralogy. Our results provide constraints for NMR determinations of pore size and permeability in marine sediments and illustrate the links between NMR properties

  18. High nuclearity complexes of lanthanide involving tetrathiafulvalene ligands: structural, magnetic, and photophysical properties.

    PubMed

    Pointillart, Fabrice; Le Guennic, Boris; Golhen, Stéphane; Cador, Olivier; Maury, Olivier; Ouahab, Lahcène

    2013-02-04

    The reaction between the tetrakis(2-pyridyl-N-oxidemethylthio)tetrathiafulvalene ligand (L) and Ln(hfac)(3)·2H(2)O precursors (where hfac(-) = 1,1,1,5,5,5-hexafluoroacetylacetonate anion and Ln = Tb(III) (1), Dy(III) (2), Er(III) (3), and Yb(III) (4) and (4b)) leads to the formation of five tetranuclear complexes of formula [Ln(4)(hfac)(12)(L)(2)](n)·xCHCl(3)·yC(6)H(14) (n = 1, x = 2, y = 0 for (1), (2), and (4), n = 1, x = 4 for (3), and n = 2, x = 2.5, y = 1 for (4b)). Their X-ray structures reveal that the surrounding of each Ln(III) center is filled by two N-oxide groups coming from two different ligands L. These tetranuclear complexes have the highest nuclearity which is reported until now for coordination compounds of lanthanide involving TTF-based ligands. Direct current (dc) measurements highlight the paramagnetic behavior of the compounds with a significant crystal field effect. The temperature dependences of static magnetic measurements for 4 have been fitted. The ground state corresponds to M(J) = ±5/2 while the first excited state (M(J) = ±3/2) was localized at +214 cm(-1) which was well correlated with the luminescence transition. UV-visible absorption properties have been experimentally measured and rationalized by time-dependent density functional theory (TD-DFT) calculations. Upon irradiation at 77 K and room temperature, in the range 24390-20835 cm(-1), both compounds 3 and 4 display a metal-centered luminescence attributed to (4)I(13/2) → (4)I(15/2) (6660 cm(-1)) and (2)F(5/2) → (2)F(7/2) (signal centered around the value of 9966 cm(-1)) transitions, respectively. The observed six transitions could be attributed to the M(J) state splitting due to the existence of two Yb1 and Yb2 ions with slightly different polyhedra in 4.

  19. Operational level for unconditional release of contaminated property from affected areas around Fukushima Daiichi nuclear power plant

    PubMed Central

    Ogino, Haruyuki; Hattori, Takatoshi

    2013-01-01

    This paper focuses on the surface contamination control of slightly contaminated property after the Fukushima nuclear accident. The operational level for the unconditional release of contaminated properties is calculated in counts per minute (cpm) to enable the use of a typical Geiger-Muller (GM) survey meter with a 50-mm bore, on the basis of the surficial clearance level of 10 Bq cm−2 for 134Cs and 137Cs derived in the previous studies of the authors. By applying a factor for the conversion of the unit surface contamination to the count rate of a survey meter widely used after the Fukushima accident, the operational level for the unconditional release of contaminated properties was calculated to be 2300 cpm on average and 23 000 cpm at the highest-contamination part. The calculated numerical values of the operational levels are effective as long as the typical GM survey meter is used in the radiation measurement. PMID:23778575

  20. Operational level for unconditional release of contaminated property from affected areas around Fukushima Daiichi nuclear power plant.

    PubMed

    Ogino, Haruyuki; Hattori, Takatoshi

    2013-12-01

    This paper focuses on the surface contamination control of slightly contaminated property after the Fukushima nuclear accident. The operational level for the unconditional release of contaminated properties is calculated in counts per minute (cpm) to enable the use of a typical Geiger-Muller (GM) survey meter with a 50-mm bore, on the basis of the surficial clearance level of 10 Bq cm(-2) for (134)Cs and (137)Cs derived in the previous studies of the authors. By applying a factor for the conversion of the unit surface contamination to the count rate of a survey meter widely used after the Fukushima accident, the operational level for the unconditional release of contaminated properties was calculated to be 2300 cpm on average and 23 000 cpm at the highest-contamination part. The calculated numerical values of the operational levels are effective as long as the typical GM survey meter is used in the radiation measurement.

  1. Nuclear matter properties from local chiral interactions with Δ isobar intermediate states

    NASA Astrophysics Data System (ADS)

    Logoteta, Domenico; Bombaci, Ignazio; Kievsky, Alejandro

    2016-12-01

    Using two-nucleon and three-nucleon interactions derived in the framework of chiral perturbation theory (ChPT) with and without the explicit Δ isobar contributions, we calculate the energy per particle of symmetric nuclear matter and pure neutron matter in the framework of the microscopic Brueckner-Hartree-Fock approach. In particular, we present for the first time nuclear matter calculations using the new fully local in coordinate-space two-nucleon interaction at the next-to-next-to-next-to-leading-order (N3LO) of ChPT with Δ isobar intermediate states (N 3 LO Δ ) recently developed by Piarulli et al. [arXiv:1606.06335]. We find that using this N 3 LO Δ potential, supplemented with a local N2LO three-nucleon interaction with explicit Δ isobar degrees of freedom, it is possible to obtain a satisfactory saturation point of symmetric nuclear matter. For this combination of two- and three-nucleon interactions we also calculate the nuclear symmetry energy and we compare our results with the empirical constraints on this quantity obtained using the excitation energies to isobaric analog states in nuclei and using experimental data on the neutron skin thickness of heavy nuclei, finding a very good agreement in all the considered nucleonic density range. In addition, we find that the explicit inclusion of Δ isobars diminishes the strength of the three-nucleon interactions needed to get a good saturation point of symmetric nuclear matter. We also compare the results of our calculations with those obtained by other research groups using chiral nuclear interactions with different many-body methods, finding in many cases a very satisfactory agreement.

  2. Nuclear Matter Properties with the Re-evaluated Coefficients of Liquid Drop Model

    NASA Astrophysics Data System (ADS)

    Chowdhury, P. Roy; Basu, D. N.

    2006-06-01

    The coefficients of the volume, surface, Coulomb, asymmetry and pairing energy terms of the semiempirical liquid drop model mass formula have been determined by furnishing best fit to the observed mass excesses. Slightly different sets of the weighting parameters for liquid drop model mass formula have been obtained from minimizations of \\chi 2 and mean square deviation. The most recent experimental and estimated mass excesses from Audi-Wapstra-Thibault atomic mass table have been used for the least square fitting procedure. Equation of state, nuclear incompressibility, nuclear mean free path and the most stable nuclei for corresponding atomic numbers, all are in good agreement with the experimental results.

  3. Nuclear matter properties in the non-linear Walecka model at finite temperature with interaction between the σ - ω mesons

    SciTech Connect

    Costa, R. S.; Cortes, M. R.; Nunes, D. R.; Batista, A. S. A.

    2014-11-11

    In this work in contrast to the usual Walecka model [1] we include the interaction between the σ – ω mesons [2,3] with the aim of studying the nuclear matter properties in the relativistic mean-field theory in the regime of high temperatures. Therefore in our work we use the non-linear Walecka model. We investigate whether the phase transition characteristic of other models without these interactions vanishes for a given value of chemical potential μ and baryon density ρ{sub N}.

  4. Nuclear spin coherence properties of 151Eu3+ and 153Eu3+ in a Y2O3 transparent ceramic

    NASA Astrophysics Data System (ADS)

    Karlsson, J.; Kunkel, N.; Ikesue, A.; Ferrier, A.; Goldner, P.

    2017-03-01

    We have measured inhomogeneous linewidths and coherence times (T 2) of nuclear spin transitions in a Eu3+ :Y2O3 transparent ceramic by an all-optical spin echo technique. The nuclear spin echo decay curves showed a strong modulation which was attributed to interaction with Y nuclei in the host. The coherence time of the 29 MHz spin transition in 151Eu3+ was 16 ms in a small applied magnetic field. Temperature dependent measurements showed that the coherence time was constant up to 18 K and was limited by spin-lattice relaxation for higher temperatures. Nuclear spin echoes in 153Eu3+ gave much weaker signals than for the case of 151Eu3+ . The spin coherence time for the 73 MHz spin transition in 153Eu3+ was estimated to 14 ms in a small magnetic field. The study shows that the spin transitions of ceramic Eu3+ :Y2O3 have coherence properties comparable to the best rare-earth-doped materials available.

  5. Nuclear Fission

    NASA Astrophysics Data System (ADS)

    Denschlag, J. O.

    This chapter first gives a survey on the history of the discovery of nuclear fission. It briefly presents the liquid-drop and shell models and their application to the fission process. The most important quantities accessible to experimental determination such as mass yields, nuclear charge distribution, prompt neutron emission, kinetic energy distribution, ternary fragment yields, angular distributions, and properties of fission isomers are presented as well as the instrumentation and techniques used for their measurement. The contribution concentrates on the fundamental aspects of nuclear fission. The practical aspects of nuclear fission are discussed in http://dx.doi.org/10.1007/978-1-4419-0720-2_57 of Vol. 6.

  6. Mycalamide A Shows Cytotoxic Properties and Prevents EGF-Induced Neoplastic Transformation through Inhibition of Nuclear Factors

    PubMed Central

    Dyshlovoy, Sergey A.; Fedorov, Sergey N.; Kalinovsky, Anatoly I.; Shubina, Larisa K.; Bokemeyer, Carsten; Stonik, Valentin A.; Honecker, Friedemann

    2012-01-01

    Mycalamide A, a marine natural compound previously isolated from sponges, is known as a protein synthesis inhibitor with potent antitumor activity. However, the ability of this compound to prevent malignant transformation of cells has never been examined before. Here, for the first time, we report the isolation of mycalamide A from ascidian Polysincraton sp. as well as investigation of its cancer preventive properties. In murine JB6 Cl41 P+ cells, mycalamide A inhibited epidermal growth factor (EGF)-induced neoplastic transformation, and induced apoptosis at subnanomolar or nanomolar concentrations. The compound inhibited transcriptional activity of the oncogenic nuclear factors AP-1 and NF-κB, a potential mechanism of its cancer preventive properties. Induction of phosphorylation of the kinases MAPK p38, JNK, and ERK was also observed at high concentrations of mycalamide A. The drug shows promising potential for both cancer-prevention and cytotoxic therapy and should be further developed. PMID:22822368

  7. Analytical mass formula and nuclear surface properties in the ETF approximation. Part II: asymmetric nuclei

    NASA Astrophysics Data System (ADS)

    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.

  8. EQUATION OF STATE AND NEUTRON STAR PROPERTIES CONSTRAINED BY NUCLEAR PHYSICS AND OBSERVATION

    SciTech Connect

    Hebeler, K.; Lattimer, J. M.; Pethick, C. J.; Schwenk, A.

    2013-08-10

    Microscopic calculations of neutron matter based on nuclear interactions derived from chiral effective field theory, combined with the recent observation of a 1.97 {+-} 0.04 M{sub Sun} neutron star, constrain the equation of state of neutron-rich matter at sub- and supranuclear densities. We discuss in detail the allowed equations of state and the impact of our results on the structure of neutron stars, the crust-core transition density, and the nuclear symmetry energy. In particular, we show that the predicted range for neutron star radii is robust. For use in astrophysical simulations, we provide detailed numerical tables for a representative set of equations of state consistent with these constraints.

  9. Nuclear properties of the exotic high-spin isomer 178Hfm2 from collinear laser spectroscopy

    NASA Astrophysics Data System (ADS)

    Boos, N.; Le Blanc, F.; Krieg, M.; Pinard, J.; Huber, G.; Lunney, M. D.; Le Du, D.; Meunier, R.; Hussonnois, M.; Constantinescu, O.; Kim, J. B.; Briançon, Ch.; Crawford, J. E.; Duong, H. T.; Gangrski, Y. P.; Kühl, T.; Markov, B. N.; Oganessian, Yu. Ts.; Quentin, P.; Roussière, B.; Sauvage, J.

    1994-04-01

    The complete hyperfine spectrum in the optical transition 5d26s2 3P2-->5d6s26p 1P1 of 178Hfm2 was recorded by collinear laser spectroscopy using nanogram amounts of samples. The quadrupole moment and isomer shift were determined for the first time as well as a precise value and the sign of the magnetic dipole moment. The change in nuclear mean-square charge radius between the isomeric state 178Hfm2 and the ground state 178Hfg was evaluated as δ178.178m2=-0.059(9) fm2. From the hyperfine A and B factors the magnetic moment μ178m2I=+8.16(4) nuclear magnetons and the spectroscopic quadrupole moment Q178m2s=+6.00(7) b were were extracted.

  10. Surface properties of neutron-rich exotic nuclei: A source for studying the nuclear symmetry energy

    SciTech Connect

    Gaidarov, M. K.; Antonov, A. N.; Sarriguren, P.; Moya de Guerra, E.

    2011-09-15

    We study the correlation between the thickness of the neutron skin in finite nuclei and the nuclear symmetry energy for isotopic chains of even-even Ni, Sn, and Pb nuclei in the framework of the deformed self-consistent mean-field Skyrme HF + BCS method. The symmetry energy, the neutron pressure, and the asymmetric compressibility in finite nuclei are calculated within the coherent density fluctuation model using the symmetry energy as a function of density within the Brueckner energy density functional. The mass dependence of the nuclear symmetry energy and the neutron-skin thickness are also studied together with the role of the neutron-proton asymmetry. A correlation between the parameters of the equation of state (symmetry energy and its density slope) and the neutron skin is suggested in the isotopic chains of Ni, Sn, and Pb nuclei.

  11. Warm unstable asymmetric nuclear matter: Critical properties and the density dependence of the symmetry energy

    NASA Astrophysics Data System (ADS)

    Alam, N.; Pais, H.; Providência, C.; Agrawal, B. K.

    2017-05-01

    The spinodal instabilities in hot asymmetric nuclear matter and some important critical parameters derived thereof are studied by using six different families of relativistic mean-field models. The slopes of the symmetry energy coefficient vary over a wide range within each family. The critical densities and proton fractions are more sensitive to the symmetry energy slope parameter at temperatures much below its critical value (Tc˜14 -16 MeV ). The spread in the critical proton fraction at a given symmetry energy slope parameter is noticeably larger near Tc, indicating that the equation of state of warm asymmetric nuclear matter at subsaturation densities is not sufficiently constrained. The distillation effects are sensitive to the density dependence of the symmetry energy at low temperatures which tend to wash out with increasing temperature.

  12. Mineralogy and thermodynamic properties of magnesium phyllosilicates formed during the alteration of a simplified nuclear glass

    NASA Astrophysics Data System (ADS)

    Debure, Mathieu; De Windt, Laurent; Frugier, Pierre; Gin, Stéphane; Vieillard, Philippe

    2016-07-01

    The precipitation of crystallized magnesium phyllosilicates generally sustains the alteration rate of nuclear waste containment glass. However, glass alteration slows down to a residual rate as soon as Mg disappears from the solution. The identification of the phyllosilicates formed is therefore crucial for modeling the long-term behavior of nuclear glass. This study deals with batch alteration of the simplified nuclear glass ISG in presence of magnesium, and the characterization of the secondary phases. Morphological, chemical and structural analyses (MET, EDX, XRD) were performed to determine the nature and structure of the precipitated phases identified as trioctahedral smectites. Analyses conducted on the secondary phases proved the presence of Al, Na and Ca in the Mg-phyllosilicate phases. Such elements had been suspected but never quantitatively measured. The experimental results were then used to determine the thermodynamic solubility constants for each precipitated secondary phase at various temperatures. The calculated values were consistent with those available for sodium and magnesium saponites in the existing thermodynamic databases.

  13. Nuclear localization of tricellulin promotes the oncogenic property of pancreatic cancer

    PubMed Central

    Takasawa, Akira; Murata, Masaki; Takasawa, Kumi; Ono, Yusuke; Osanai, Makoto; Tanaka, Satoshi; Nojima, Masanori; Kono, Tsuyoshi; Hirata, Koichi; Kojima, Takashi; Sawada, Norimasa

    2016-01-01

    Accumulating evidence has shown that dysregulation of tight junctions (TJs) is involved in tumor development and progression. In this study, we investigated the expression and subcellular distribution of tricellulin, which constitutes tricellular TJs, using human pancreatic adenocarcinomas. In well-differentiated pancreatic adenocarcinoma tissues, tricellulin immunostaining was prominent in the cytoplasm and the plasma membrane. In contrast, in poorly differentiated tissues, its immunostaining was predominantly observed in the nuclei and was almost absent in the plasma membrane. The distinct immunostaining of tricellulin successfully distinguished poorly differentiated adenocarcinoma from moderately and well-differentiated adenocarcinomas with high levels of sensitivity and specificity. Nuclear tricellulin expression significantly correlated with lymph node metastasis, lymphatic invasion and poor survival. In pancreatic cancer cell lines, tricellulin localization shifted from the membrane to nucleus with decreasing differentiation status. Nuclear localization of tricellulin promoted cell proliferation and invasiveness possibly in association with MAPK and PKC pathways in pancreatic cancers. Our results provide new insights into the function of tricellulin, and its nuclear localization may become a new prognostic factor for pancreatic cancers. PMID:27641742

  14. Deflection by Kinetic Impact or Nuclear Ablation: Sensitivity to Asteroid Properties

    NASA Astrophysics Data System (ADS)

    Bruck Syal, M.

    2015-12-01

    Impulsive deflection of a threatening asteroid can be achieved by deploying either a kinetic impactor or a standoff nuclear device to impart a modest velocity change to the body. Response to each of these methods is sensitive to the individual asteroid's characteristics, some of which may not be well constrained before an actual deflection mission. Numerical simulations of asteroid deflection, using both hypervelocity impacts and nuclear ablation of the asteroid's surface, provide detailed information on asteroid response under a range of initial conditions. Here we present numerical results for the deflection of asteroids by both kinetic and nuclear methods, focusing on the roles of target body composition, strength, porosity, rotational state, shape, and internal structure. These results provide a framework for evaluating the planetary defense-related value of future asteroid characterization missions and capture some of the uncertainty that may be present in a real threat scenario. Part of this work was funded by the Laboratory Directed Research and Development Program at LLNL under project tracking code 12-ERD-005, performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. LLNL-ABS-675914.

  15. AMUSE-Field I: NUCLEAR X-RAY PROPERTIES OF LOCAL FIELD AND GROUP SPHEROIDS ACROSS THE STELLAR MASS SCALE

    SciTech Connect

    Miller, Brendan; Gallo, Elena; Treu, Tommaso; Woo, Jong-Hak

    2012-03-01

    We present the first results from AMUSE-Field, a Chandra survey designed to characterize the occurrence and intensity of low-level accretion onto supermassive black holes (SMBHs) at the center of local early-type field galaxies. This is accomplished by means of a Large Program targeting a distance-limited (<30 Mpc) sample of 103 early types spanning a wide range in stellar masses. We acquired new ACIS-S observations for 61 objects down to a limiting (0.3-10 keV) luminosity of 2.5 Multiplication-Sign 10{sup 38} erg s{sup -1}, and we include an additional 42 objects with archival (typically deeper) coverage. A nuclear X-ray source is detected in 52 out of the 103 galaxies. After accounting for potential contamination from low-mass X-ray binaries, we estimate that the fraction of accreting SMBHs within the sample is 45% {+-} 7%, which sets a firm lower limit on the occupation fraction within the field. The measured nuclear X-ray luminosities are invariably highly sub-Eddington, with L{sub X}/L{sub Edd} ratios between {approx}10{sup -4} and 10{sup -8}. As also found in a companion survey targeting Virgo early types, the active fraction increases with increasing host galaxy stellar mass, reflective of 'Eddington incompleteness' within the lower-mass objects. For the Field sample, the average nuclear X-ray luminosity scales with the host stellar mass as M{sup 0.71{+-}0.10}{sub star}, with an intrinsic scatter of 0.73 {+-} 0.09 dex. Qualitatively similar results hold for morphologically homogeneous (type E) or uniform sensitivity (new observations only) subsets. A majority of the AMUSE-Field galaxies (78%) inhabit groups, enabling us to investigate the influence of group richness on nuclear activity. We see no evidence for a positive correlation between nuclear X-ray luminosity, normalized to host properties, and galaxy density. Rather, while the scatter is substantial, it appears that the Eddington-scaled X-ray luminosity of group members may be slightly lower than for

  16. AMUSE-Field I: Nuclear X-Ray Properties of Local Field and Group Spheroids across the Stellar Mass Scale

    NASA Astrophysics Data System (ADS)

    Miller, Brendan; Gallo, Elena; Treu, Tommaso; Woo, Jong-Hak

    2012-03-01

    We present the first results from AMUSE-Field, a Chandra survey designed to characterize the occurrence and intensity of low-level accretion onto supermassive black holes (SMBHs) at the center of local early-type field galaxies. This is accomplished by means of a Large Program targeting a distance-limited (<30 Mpc) sample of 103 early types spanning a wide range in stellar masses. We acquired new ACIS-S observations for 61 objects down to a limiting (0.3-10 keV) luminosity of 2.5 × 1038 erg s-1, and we include an additional 42 objects with archival (typically deeper) coverage. A nuclear X-ray source is detected in 52 out of the 103 galaxies. After accounting for potential contamination from low-mass X-ray binaries, we estimate that the fraction of accreting SMBHs within the sample is 45% ± 7%, which sets a firm lower limit on the occupation fraction within the field. The measured nuclear X-ray luminosities are invariably highly sub-Eddington, with L X/L Edd ratios between ~10-4 and 10-8. As also found in a companion survey targeting Virgo early types, the active fraction increases with increasing host galaxy stellar mass, reflective of "Eddington incompleteness" within the lower-mass objects. For the Field sample, the average nuclear X-ray luminosity scales with the host stellar mass as M 0.71 ± 0.10 star, with an intrinsic scatter of 0.73 ± 0.09 dex. Qualitatively similar results hold for morphologically homogeneous (type E) or uniform sensitivity (new observations only) subsets. A majority of the AMUSE-Field galaxies (78%) inhabit groups, enabling us to investigate the influence of group richness on nuclear activity. We see no evidence for a positive correlation between nuclear X-ray luminosity, normalized to host properties, and galaxy density. Rather, while the scatter is substantial, it appears that the Eddington-scaled X-ray luminosity of group members may be slightly lower than for isolated galaxies, and that this trend continues to cluster early types.

  17. Evaluation of Mechanical Properties of Nuclear Materials Using Non-Destructive Ball Indentation Technique

    SciTech Connect

    Mathew, M.D.; Linga Murty, K.

    2002-07-01

    Integrity of structural components depends on the deformation and fracture behavior of materials. For evaluating the material condition in-service, it is generally not feasible or practical or advisable to cut samples from operating structures. Non-destructive testing (NDT) techniques are required to evaluate the mechanical properties. Although several NDT techniques such as ultrasound, magnetic strength, Barkhausen noise, microhardness etc., are employed for estimating the mechanical property degradation, these methodologies are generally empirical and indirect. Automated Ball Indentation (ABI) is a non-destructive testing technique for direct measurement of mechanical and fracture properties of metallic engineering materials. Because of the small area over which the test is carried out, it is possible to determine point to point variations in the mechanical and fracture properties, such as those that exist in weldments. Although ABI technique is non-intrusive, it is a state-of-the-art mechanical test that measures directly the current/local deformation behavior of the material. In this paper, we present results from studies on the application of ABI technique to determine tensile and fracture properties of ferritic steels, an austenitic stainless steel, a nickel base superalloy and Zircaloy in different thermo-mechanical conditions. The effects of aging and cold work on these properties were determined from the ABI tests. Gradients in mechanical properties of ferritic steel welds, particularly in the narrow heat-affected zone, were clearly established. ABI technique was found to be useful in determining the anisotropy in the tensile properties of Zircaloy cladding tubes. The technique has potential as a non-destructive method for assessing structural integrity of aged components. (authors)

  18. Investigation of the Electronic Properties of Cadmium Zinc Telluride (CZT) Detectors using a Nuclear Microprobe

    SciTech Connect

    BRUNETT,BRUCE A.; DOYLE,BARNEY L.; JAMES,RALPH B.; VIZKELETHY,GYORGY; WALSH,DAVID S.

    1999-10-18

    The electronic transport properties of Cadmium Zinc Telluride (CZT) determine the charge collection efficiency (i.e. the signal quality) of CZT detectors. These properties vary on both macroscopic and microscopic scale and depend on the presence of impurities and defects introduced during the crystal growth. Ion Beam Induced Charge Collection (IBICC) is a proven method to measure the charge collection efficiency. Using an ion microbeam, the charge collection efficiency can be mapped with submicron resolution, and the map of electronic properties (such as drift length) can be calculated from the measurement. A more sophisticated version of IBICC, the Time Resolved IBICC (TRIBICC) allows them to determine the mobility and the life time of the charge carriers by recording and analyzing the transient waveform of the detector signal. Furthermore, lateral IBICC and TRIBICC can provide information how the charge collection efficiency depends on the depth where the charge carriers are generated. This allows one to deduce information on the distribution of the electric field and transport properties of the charge carriers along the detector axis. IBICC and TRIBICC were used at the Sandia microbeam facility to image electronic properties of several CZT detectors. From the lateral TRIBICC measurement the electron and hole drift length profiles were calculated.

  19. In silico modelling of prostacyclin and other lipid mediators to nuclear receptors reveal novel thyroid hormone receptor antagonist properties.

    PubMed

    Perez Diaz, Noelia; Zloh, Mire; Patel, Pryank; Mackenzie, Louise S

    2016-01-01

    Prostacyclin (PGI2) is a key mediator involved in cardiovascular homeostasis, acting predominantly on two receptor types; cell surface IP receptor and cytosolic peroxisome proliferator activated receptor (PPAR) β/δ. Having a very short half-life, direct methods to determine its long term effects on cells is difficult, and little is known of its interactions with nuclear receptors. Here we used computational chemistry methods to investigate the potential for PGI2, beraprost (IP receptor agonist), and GW0742 (PPARβ/δ agonist), to bind to nuclear receptors, confirmed with pharmacological methods. In silico screening predicted that PGI2, beraprost, and GW0742 have the potential to bind to different nuclear receptors, in particular thyroid hormone β receptor (TRβ) and thyroid hormone α receptor (TRα). Docking analysis predicts a binding profile to residues thought to have allosteric control on the TR ligand binding site. Luciferase reporter assays confirmed that beraprost and GW0742 display TRβ and TRα antagonistic properties; beraprost IC50 6.3 × 10(-5)mol/L and GW0742 IC50 4.9 × 10(-6) mol/L. Changes to triiodothyronine (T3) induced vasodilation of rat mesenteric arteries measured on the wire myograph were measured in the presence of the TR antagonist MLS000389544 (10(-5) mol/L), beraprost (10(-5) mol/L) and GW0742 (10(-5) mol/L); all significantly inhibited T3 induced vasodilation compared to controls. We have shown that both beraprost and GW0742 exhibit TRβ and TRα antagonist behaviour, and suggests that PGI2 has the ability to affect the long term function of cells through binding to and inactivating thyroid hormone receptors. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. A probabilistic approach to rock mechanical property characterization for nuclear waste repository design

    SciTech Connect

    Kim, Kunsoo; Gao, Hang

    1996-04-01

    A probabilistic approach is proposed for the characterization of host rock mechanical properties at the Yucca Mountain site. This approach helps define the probability distribution of rock properties by utilizing extreme value statistics and Monte Carlo simulation. We analyze mechanical property data of tuff obtained by the NNWSI Project to assess the utility of the methodology. The analysis indicates that laboratory measured strength and deformation data of Calico Hills and Bullfrog tuffs follow an extremal. probability distribution (the third type asymptotic distribution of the smallest values). Monte Carlo simulation is carried out to estimate rock mass deformation moduli using a one-dimensional tuff model proposed by Zimmermann and Finley. We suggest that the results of these analyses be incorporated into the repository design.

  1. Bulk nuclear properties from dynamical description of heavy-ion collisions

    NASA Astrophysics Data System (ADS)

    Hong, Jun

    Mapping out the equation of state (EOS) of nuclear matter is a long standing problem in nuclear physics. Both experimentalists and theoretical physicists spare no effort in improving understanding of the EOS. In this thesis, we examine observables sensitive to the EOS within the pBUU transport model based on the Boltzmann equation. By comparing theoretical predictions with experimental data, we arrive at new constraints for the EOS. Further we propose novel promising observables for analysis of future experimental data. One set of observables that we examine within the pBUU model are pion yields. First, we find that net pion yields in central heavy-ion collisions (HIC) are strongly sensitive to the momentum dependence of the isoscalar nuclear mean field. We reexamine the momentum dependence that is assumed in the Boltzmann equation model for the collisions and optimize that dependence to describe the FOPI measurements of pion yields from the Au+Au collisions at different beam energies. Alas such optimized dependence yields a somewhat weaker baryonic elliptic flow than seen in measurements. Subsequently, we use the same pBUU model to generate predictions for baryonic elliptic flow observable in HIC, while varying the incompressibility of nuclear matter. In parallel, we test the sensitivity of pion multiplicity to the density dependence of EOS, and in particular to incompressibility, and optimize that dependence to describe both the elliptic flow and pion yields. Upon arriving at acceptable regions of density dependence of pressure and energy, we compare our constraints on EOS with those recently arrived at by the joint experiment and theory effort FOPI-IQMD. We should mention that, for the more advanced observables from HIC, there remain discrepancies of up to 30%, depending on energy, between the theory and experiment, indicating the limitations of the transport theory. Next, we explore the impact of the density dependence of the symmetry energy on observables

  2. Development and property evaluation of nuclear grade wrought FeCrAl fuel cladding for light water reactors

    SciTech Connect

    Yamamoto, Yukinori; Pint, Bruce A.; Terrani, Kurt A.; Field, Kevin G.; Yang, Ying; Snead, Lance Lewis

    2015-10-19

    Development of nuclear grade, iron-based wrought FeCrAl alloys has been initiated for light water reactor (LWR) fuel cladding to serve as a substitute for zirconium-based alloys with enhanced accident tolerance. Ferritic alloys with sufficient chromium and aluminum additions can exhibit significantly improved oxidation kinetics in high-temperature steam environments when compared to zirconium-based alloys. In the first phase, a set of model FeCrAl alloys containing 10–20Cr, 3–5Al, and 0–0.12Y in weight percent, were prepared by conventional arc-melting and hot-working processes to explore the effect of composition on the properties of FeCrAlY alloys. It was found that the tensile properties were insensitive to the alloy compositions studied; however, the steam oxidation resistance strongly depended on both the chromium and the aluminum contents. The second phase development focused on strengthening Fe-13Cr-5Al with minor alloying additions of molybdenum, niobium, and silicon. Combined with an optimized thermo-mechanical treatment, a thermally stable microstructure was produced with improved tensile properties at temperatures up to 741°C.

  3. Development and property evaluation of nuclear grade wrought FeCrAl fuel cladding for light water reactors

    NASA Astrophysics Data System (ADS)

    Yamamoto, Y.; Pint, B. A.; Terrani, K. A.; Field, K. G.; Yang, Y.; Snead, L. L.

    2015-12-01

    Development of nuclear grade, iron-based wrought FeCrAl alloys has been initiated for light water reactor (LWR) fuel cladding to serve as a substitute for zirconium-based alloys with enhanced accident tolerance. Ferritic alloys with sufficient chromium and aluminum additions can exhibit significantly improved oxidation kinetics in high-temperature steam environments when compared to zirconium-based alloys. In the first phase, a set of model FeCrAl alloys containing 10-20Cr, 3-5Al, and 0-0.12Y in weight percent, were prepared by conventional arc-melting and hot-working processes to explore the effect of composition on the properties of FeCrAlY alloys. It was found that the tensile properties were insensitive to the alloy compositions studied; however, the steam oxidation resistance strongly depended on both the chromium and the aluminum contents. The second phase development focused on strengthening Fe-13Cr-5Al with minor alloying additions of molybdenum, niobium, and silicon. Combined with an optimized thermo-mechanical treatment, a thermally stable microstructure was produced with improved tensile properties at temperatures up to 741 °C.

  4. Development and property evaluation of nuclear grade wrought FeCrAl fuel cladding for light water reactors

    DOE PAGES

    Yamamoto, Yukinori; Pint, Bruce A.; Terrani, Kurt A.; ...

    2015-10-19

    Development of nuclear grade, iron-based wrought FeCrAl alloys has been initiated for light water reactor (LWR) fuel cladding to serve as a substitute for zirconium-based alloys with enhanced accident tolerance. Ferritic alloys with sufficient chromium and aluminum additions can exhibit significantly improved oxidation kinetics in high-temperature steam environments when compared to zirconium-based alloys. In the first phase, a set of model FeCrAl alloys containing 10–20Cr, 3–5Al, and 0–0.12Y in weight percent, were prepared by conventional arc-melting and hot-working processes to explore the effect of composition on the properties of FeCrAlY alloys. It was found that the tensile properties were insensitivemore » to the alloy compositions studied; however, the steam oxidation resistance strongly depended on both the chromium and the aluminum contents. The second phase development focused on strengthening Fe-13Cr-5Al with minor alloying additions of molybdenum, niobium, and silicon. Combined with an optimized thermo-mechanical treatment, a thermally stable microstructure was produced with improved tensile properties at temperatures up to 741°C.« less

  5. Phylogenetic properties of 50 nuclear loci in Medicago (Leguminosae) generated using multiplexed sequence capture and next-generation sequencing.

    PubMed

    de Sousa, Filipe; Bertrand, Yann J K; Nylinder, Stephan; Oxelman, Bengt; Eriksson, Jonna S; Pfeil, Bernard E

    2014-01-01

    Next-generation sequencing technology has increased the capacity to generate molecular data for plant biological research, including phylogenetics, and can potentially contribute to resolving complex phylogenetic problems. The evolutionary history of Medicago L. (Leguminosae: Trifoliae) remains unresolved due to incongruence between published phylogenies. Identification of the processes causing this genealogical incongruence is essential for the inference of a correct species phylogeny of the genus and requires that more molecular data, preferably from low-copy nuclear genes, are obtained across different species. Here we report the development of 50 novel LCN markers in Medicago and assess the phylogenetic properties of each marker. We used the genomic resources available for Medicago truncatula Gaertn., hybridisation-based gene enrichment (sequence capture) techniques and Next-Generation Sequencing to generate sequences. This alternative proves to be a cost-effective approach to amplicon sequencing in phylogenetic studies at the genus or tribe level and allows for an increase in number and size of targeted loci. Substitution rate estimates for each of the 50 loci are provided, and an overview of the variation in substitution rates among a large number of low-copy nuclear genes in plants is presented for the first time. Aligned sequences of major species lineages of Medicago and its sister genus are made available and can be used in further probe development for sequence-capture of the same markers.

  6. Phylogenetic Properties of 50 Nuclear Loci in Medicago (Leguminosae) Generated Using Multiplexed Sequence Capture and Next-Generation Sequencing

    PubMed Central

    de Sousa, Filipe; Bertrand, Yann J. K.; Nylinder, Stephan; Oxelman, Bengt; Eriksson, Jonna S.; Pfeil, Bernard E.

    2014-01-01

    Next-generation sequencing technology has increased the capacity to generate molecular data for plant biological research, including phylogenetics, and can potentially contribute to resolving complex phylogenetic problems. The evolutionary history of Medicago L. (Leguminosae: Trifoliae) remains unresolved due to incongruence between published phylogenies. Identification of the processes causing this genealogical incongruence is essential for the inference of a correct species phylogeny of the genus and requires that more molecular data, preferably from low-copy nuclear genes, are obtained across different species. Here we report the development of 50 novel LCN markers in Medicago and assess the phylogenetic properties of each marker. We used the genomic resources available for Medicago truncatula Gaertn., hybridisation-based gene enrichment (sequence capture) techniques and Next-Generation Sequencing to generate sequences. This alternative proves to be a cost-effective approach to amplicon sequencing in phylogenetic studies at the genus or tribe level and allows for an increase in number and size of targeted loci. Substitution rate estimates for each of the 50 loci are provided, and an overview of the variation in substitution rates among a large number of low-copy nuclear genes in plants is presented for the first time. Aligned sequences of major species lineages of Medicago and its sister genus are made available and can be used in further probe development for sequence-capture of the same markers. PMID:25329401

  7. Analysis of filamentous process induction and nuclear localization properties of the HSV-2 serine/threonine kinase Us3

    SciTech Connect

    Finnen, Renee L.; Roy, Bibhuti B.; Zhang Hui; Banfield, Bruce W.

    2010-02-05

    The Us3 serine/threonine kinase encoded by all alphaherpesviruses performs several important functions during virus multiplication. For example, expression of pseudorabies virus (PRV) Us3 causes reorganization of the actin cytoskeleton into filamentous processes (FPs) that promote cell-to-cell spread of virus infection. PRV Us3-induced FP formation requires Us3 kinase activity. To determine whether these characteristics were shared by HSV-2 Us3, expression plasmids for wild type (WT) and kinase dead (KD) Us3 variants were constructed. Expression of WT Us3 resulted in robust FP formation whereas expression of the KD Us3 variants did not. In the course of these experiments we noted that KD/K220 mutant Us3s were excluded from the nucleus in comparison to WT or KD/D305A Us3, prompting us to investigate Us3 nuclear shuttling properties. Herein we describe determinants of HSV-2 Us3-induced FP formation and present evidence for the presence of a leucine-rich nuclear export signal within HSV-2 Us3.

  8. Physicochemical properties of aerosol released in the case of a fire involving materials used in the nuclear industry.

    PubMed

    Ouf, F-X; Mocho, V-M; Pontreau, S; Wang, Z; Ferry, D; Yon, J

    2015-01-01

    For industrial concerns, and more especially for nuclear applications, the characterization of soot is essential for predicting the behaviour of containment barriers in fire conditions. This study deals with the characterization (emission factor, composition, size, morphology, microstructure) of particles produced during thermal degradation of materials found in nuclear facilities (electrical cables, polymers, oil and solvents). Small-scale experiments have been conducted for oxygen concentrations [O2] ranging from 15% to 21% in order to imitate the oxygen depletion encountered during a confined fire. Particles denote distinct shapes, from aggregates composed of monomers with diameters ranging from 31.2 nm to 52.8 nm, to compact nanoparticles with diameters ranging from 15 nm to 400 nm, and their composition strongly depends on fuel type. Despite the organic to total carbon ratio (OC/TC), their properties are poorly influenced by the decrease in [O2]. Finally, two empirical correlations are proposed for predicting the OC/TC ratio and the monomer diameter, respectively, as a function of the fuel's carbon to hydrogen ratio and the emission factor. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Nuclear-data input to the classical r-process: The case of β-decay properties

    NASA Astrophysics Data System (ADS)

    Kratz, Karl-Ludwig; Farouqi, Khalil; Pfeiffer, Bernd

    2017-06-01

    Attempts to explain the origin of r-process elements in our Solar System (S.S.) still face entwined uncertainties, stemming from the extrapolation of nuclear structure from the line of β-stability to the neutron drip line, inconsistent sources of different properties (e.g. nuclear masses and β-decay quantities), and the poor understanding of astrophysical conditions, which are often hard to disentangle. In this paper, we will focus on the two interrelated gross β-decay quantities T1/2 and Pn. We compare the recent experimental T1/2 of very neutron-rich isotopes in the 36Kr to 50Sn region (measured at RIKEN) with consistent QRPA(GT+ff) predictions based on the two global deformed mass models ETFSI-Q(1996) and FRDM(2012). Analyzing the observed agreement and remaining deficiencies of the T1/2 trends, we predict the still unknown β-delayed neutron-emission probabilities (Pn) for these isotopes using the empirical Kratz-Herrmann formula (KHF) and the microscopic ETFSI-Q/QRPA(GT+ff) model combination.

  10. Prediction of low-field nuclear singlet lifetimes with molecular dynamics and quantum-chemical property surface.

    PubMed

    Håkansson, Pär

    2017-01-25

    Molecular dynamics and quantum chemistry methods are implemented to quantify nuclear spin-1/2 pair singlet-state relaxation rates for three molecular systems at low magnetic field and room temperature. Computational methodology is developed for weak interactions, particularly important for singlet states at low field. These include spin-rotation and spin-internal-motion effects, which describe the coupling of the spin-carrying nuclei to fluctuating local magnetic fields induced by the overall and internal molecular fluctuations, respectively. A high-dimensional tensor property surface using Kriging interpolation is developed to circumvent costly quantum-chemical calculations. Together with the intramolecular dipolar relaxation, all the simulated relaxation mechanisms are accounted for with a common theoretical framework. Comparison with experiment indicates that quantitative accuracy is obtained, sufficient to enable guidance in the molecular design of molecules with long-lived singlet order.

  11. Improved mechanical properties of A 508 class 3 steel for nuclear pressure vessel through steelmaking

    SciTech Connect

    Kim, J.T.; Kwon, H.K.; Kim, K.C.; Kim, J.M.

    1997-12-31

    The present work is concerned with the steelmaking practices which improve the mechanical properties of the A 508 class 3 steel for reactor pressure vessel. Three kinds of steelmaking practices were applied to manufacture the forged heavy wall shell for reactor pressure vessel, that is, the vacuum carbon deoxidation (VCD), modified VCD containing aluminum and silicon-killing. The segregation of the chemical elements through the thickness was quite small so that the variations of the tensile properties at room temperature were small and the anisotropy of the impact properties was hardly observed regardless of the steelmaking practices. The Charpy V-notch impact properties and the reference nil-ductile transition temperature by drop weight test were significantly improved by the modified VCD and silicon-killing as compared with those of the steel by VCD. Moreover, the plane strain fracture toughness values of the materials by modified VCD and silicon-killing practices was much higher than those of the steel by VCD. These were resulted from the fining of austenite grain size. It was observed that the grain size was below 20 {micro}m (ASTM No. 8.5) when using the modified VCD and silicon-killing, compared to 50 {micro}m (ASTM No. 7.0) when using VCD.

  12. NMR crystallography: structure and properties of materials from solid-state nuclear magnetic resonance observables.

    PubMed

    Bryce, David L

    2017-07-01

    This topical review provides a brief overview of recent developments in NMR crystallography and related NMR approaches to studying the properties of molecular and ionic solids. Areas of complementarity with diffraction-based methods are underscored. These include the study of disordered systems, of dynamic systems, and other selected examples where NMR can provide unique insights. Highlights from the literature as well as recent work from my own group are discussed.

  13. Adenovirus replication is coupled with the dynamic properties of the PML nuclear structure.

    PubMed

    Doucas, V; Ishov, A M; Romo, A; Juguilon, H; Weitzman, M D; Evans, R M; Maul, G G

    1996-01-15

    Wild-type PML and at least four other novel proteins are localized within discrete nuclear structures known as PODs. We demonstrate here that during adenovirus infection, immediate early viral proteins from the E1 and E4 transcription units associate with the POD, which in turn undergoes a dramatic morphological change. During this process, the auto-antigen Sp-100 and NDP55 but not PML, relocate from the POD to the viral inclusion bodies, the sites of adenovirus DNA replication and late RNA transcription. The E4-ORF3 11-kD protein alone will induce this reorganization and reciprocally, viruses carrying mutations in the E4-domain fail to do so. These same viral mutants are defective in viral replication as well as the accumulation of late viral mRNAs and host cell transcription shutoff. We show that interferon (INF) treatment enhances the expression of PML, reduces or blocks PODs reorganization, and inhibits BrdU incorporation into viral inclusion bodies. In addition, cell lines engineered to overexpress PML prevent PODs from viral-induced reorganization and block or severely delay adenovirus replication. These results suggest that viral replication relies on components of the POD and that the structure is a target of early viral proteins.

  14. In vivo aggregation properties of the nuclear poly(A)-binding protein PABPN1.

    PubMed

    Tavanez, João Paulo; Calado, Patricia; Braga, José; Lafarga, Miguel; Carmo-Fonseca, Maria

    2005-05-01

    A broad range of degenerative diseases is associated with intracellular inclusions formed by toxic, aggregation-prone mutant proteins. Intranuclear inclusions constitute a pathological hallmark of oculopharyngeal muscular dystrophy (OPMD), a dominantly inherited disease caused by (GCG) repeat expansions in the gene that encodes for nuclear poly(A) binding protein (PABPN1). The mutation results in an extended polyalanine stretch that has been proposed to induce protein aggregation and formation of intranuclear inclusions. Here we show that normal PABPN1 is inherently aggregation-prone when exogenously expressed in either HeLa or myogenic C2 cells. Similar deposits of insoluble PABPN1 are formed by variant forms of the protein containing either a polyalanine expansion or a complete deletion of the polyalanine tract, indicating that the mutation responsible for OPMD is not essential for formation of PABPN1 inclusions. In contrast, interfering with any of the protein domains required for stimulation of poly(A) polymerase prevents the formation of inclusions. Most surprisingly, photobleaching experiments reveal that both normal and expanded PABPN1 molecules are not irreversibly sequestered into aggregates, but rather move rapidly in and out of the inclusions. These findings have important implications for the interpretation of OPMD model systems based on exogenous expression of PABPN1.

  15. Dynamical properties of nuclear and stellar matter and the symmetry energy

    SciTech Connect

    Pais, Helena; Santos, Alexandre; Brito, Lucilia; Providencia, Constanca

    2010-08-15

    The effects of density dependence of the symmetry energy on the collective modes and dynamical instabilities of cold and warm nuclear and stellar matter are studied in the framework of relativistic mean-field hadron models. The existence of the collective isovector and possibly an isoscalar collective mode above saturation density is discussed. It is shown that soft equations of state do not allow for a high-density isoscalar collective mode; however, if the symmetry energy is hard enough, an isovector mode will not disappear at high densities. The crust-core transition density and pressure are obtained as a function of temperature for {beta}-equilibrium matter with and without neutrino trapping. Estimations of the size of the clusters formed in the nonhomogeneous phase, as well as the corresponding growth rates and distillation effect, are made. It is shown that cluster sizes increase with temperature, that the distillation effect close to the inner edge of the crust-core transition is very sensitive to the symmetry energy, and that, within a dynamical instability calculation, the pasta phase exists in warm compact stars up to 10-12 MeV.

  16. IFU spectroscopy of 10 early-type galactic nuclei - II. Nuclear emission line properties

    NASA Astrophysics Data System (ADS)

    Ricci, T. V.; Steiner, J. E.; Menezes, R. B.

    2014-05-01

    Although it is well known that massive galaxies have central black holes, most of them accreting at low Eddington ratios, many important questions still remain open. Among them are the nature of the ionizing source, the characteristics and frequencies of the broad-line region and of the dusty torus. We report observations of 10 early-type galactic nuclei, observed with the Gemini Multi Object Spectrograph in integral field unit mode, installed on the Gemini South telescope, analysed with standard techniques for spectral treatment and compared with results obtained with principal component analysis Tomography (Paper I). We performed spectral synthesis of each spaxel of the data cubes and subtracted the stellar component from the original cube, leaving a data cube with emission lines only. The emission lines were decomposed in multi-Gaussian components. We show here that, for eight galaxies previously known to have emission lines, the narrow-line region can be decomposed in two components with distinct line widths. In addition to this, broad Hα emission was detected in six galaxies. The two galaxies not previously known to have emission lines show weak Hα+[N II] lines. All 10 galaxies may be classified as low-ionization nuclear emission regions in diagnostic diagrams and seven of them have bona fide active galactic nuclei with luminosities between 1040 and 1043 erg s-1. Eddington ratios are always <10-3.

  17. Using Surface NMR Nuclear Magnetic Resonance to Determine Sediment Structure and Properties Beneath Thermokarst Lakes

    NASA Astrophysics Data System (ADS)

    Creighton, A.; Parsekian, A.; Arp, C. D.; Jones, B. M.; Walter Anthony, K. M.; Bondurant, A.

    2015-12-01

    Thermokarst lakes form following the subsidence of ice-rich permafrost terrain and concurrent infilling of the depression with water. Areas of unfrozen sediment, called taliks, can form under lakes that have a mean annual bottom temperature greater than 0°C. Taliks are thought to play an important role in permafrost hydrology and carbon cycling. Sub-lake taliks can extend to depths of tens of meters, making them difficult and costly to measure by direct methods such as boreholes. Surface nuclear magnetic resonance (NMR) provides an unambiguous measurement of the liquid water content associated with unfrozen taliks; however, limitations of the measurements and the interpretation of the data still remain. Forward models were created to test the effect of varying water column thicknesses on the ability to resolve the depth and water content of taliks with parameters similar to geometries measured in late-winter field studies in the Arctic and Boreal regions of Alaska. The results of the forward modeling show that talik depth resolution decreases with a larger water column thickness, a shallower talik depth, and a lower water content. These results place constraints on our field measurements, with lakes greater than 9 m deep yielding potentially misleading inversion results. Field data was collected at a small, 4.6 m deep thermokarst lake near Fairbanks, Alaska, which had a known subsurface structure including talik depth, and available talik sediments from cores. Known subsurface structure was not used to inform the inversion model to determine how well talik depth could be resolved in lakes with unknown structure. With constraints placed on ice and water thickness, which are easily measured in the field, the blocky inversion model was able to accurately resolve the talik depth and water content for lakes less than 9 m deep.

  18. Simulation of CdTe:Ge crystal properties for nuclear radiation detectors

    NASA Astrophysics Data System (ADS)

    Sochinskii, N. V.; Lozano, M.; Pellegrini, G.; Ullan, M.

    2006-11-01

    We report on the simulation results of the electrical properties of a coplanar detector made from Ge-doped CdTe crystals. The simulations have been performed using the commercial modeling package MEDICI. The detailed models of material behavior have been created by varying the concentration of three standard traps associated with CdTe:Ge crystals. These traps are the A-center related to Cd vacancy-residual impurity complex, the Te vacancy defect and the Ge impurity. Their energetic positions were measured by photoluminescence technique. The simulation has revealed the effects of the traps on several important detector characteristics such as leakage current and electric field distribution.

  19. Thermophysical property and pore structure evolution in stressed and non-stressed neutron irradiated IG-110 nuclear graphite

    NASA Astrophysics Data System (ADS)

    Snead, L. L.; Contescu, C. I.; Byun, T. S.; Porter, W.

    2016-08-01

    The nuclear graphite, IG-110, was irradiated with and without a compressive load of 5 MPa at ∼400 °C up to 9.3 × 1025 n/m2 (E > 0.1 MeV). Following irradiation physical properties were studied to compare the effect of graphite irradiation on microstructure developed under compression and in stress-free conditions. Properties included: dimensional change, thermal conductivity, dynamic modulus, and CTE. The effect of stress on open internal porosity was determined through nitrogen adsorption. The IG-110 graphite experienced irradiation-induced creep that is differentiated from irradiation-induced swelling. Irradiation under stress resulted in somewhat greater thermal conductivity and coefficient of thermal expansion. While a significant increase in dynamic modulus occurs, no differentiation between materials irradiated with and without compressive stress was observed. Nitrogen adsorption analysis suggests a difference in pore evolution in the 0.3-40 nm range for graphite irradiated with and without stress, but this evolution is seen to be a small contributor to the overall dimensional change.

  20. Thermophysical property and pore structure evolution in stressed and non-stressed neutron irradiated IG-110 nuclear graphite

    SciTech Connect

    Snead, Lance L.; Contescu, C. I.; Byun, T. S.; Porter, W.

    2016-04-23

    The nuclear graphite, IG-110, was irradiated with and without a compressive load of 5 MPa at ~400 C up to 9.3x1025 n/m2 (E>0.1 MeV.) Following irradiation physical properties were studied to compare the effect of graphite irradiation on microstructure developed under compression and in stress-free condition. Properties included: dimensional change, thermal conductivity, dynamic modulus, and CTE. The effect of stress on open internal porosity was determined through nitrogen adsorption. The IG-110 graphite experienced irradiation-induced creep that is differentiated from irradiation-induced swelling. Irradiation under stress resulted in somewhat greater thermal conductivity and coefficient of thermal expansion. While a significant increase in dynamic modulus occurs, no differentiation between materials irradiated with and without compressive stress was observed. Nitrogen adsorption analysis suggests a difference in pore evolution in the 0.3-40 nm range for graphite irradiated with and without stress, but this evolution is seen to be a small contributor to the overall dimensional change.

  1. Thermophysical property and pore structure evolution in stressed and non-stressed neutron irradiated IG-110 nuclear graphite

    SciTech Connect

    Snead, Lance; Contescu, Christian I.; Byun, Thak Sang; Porter, Wallace D.

    2016-08-01

    The nuclear graphite, IG-110, was irradiated with and without a compressive load of 5 MPa at ~400 *C up to 9.3E25 n/m2 (E > 0.1 MeV). Following irradiation physical properties were studied to compare the effect of graphite irradiation on microstructure developed under compression and in stress-free conditions. Properties included: dimensional change, thermal conductivity, dynamic modulus, and CTE. The effect of stress on open internal porosity was determined through nitrogen adsorption. The IG-110 graphite experienced irradiation-induced creep that is differentiated from irradiation-induced swelling. Irradiation under stress resulted in somewhat greater thermal conductivity and coefficient of thermal expansion. While a significant increase in dynamic modulus occurs, no differentiation between materials irradiated with and without compressive stress was observed. Nitrogen adsorption analysis suggests a difference in pore evolution in the 0.3e40 nm range for graphite irradiated with and without stress, but this evolution is seen to be a small contributor to the overall dimensional change.

  2. Laboratory characterization of hydraulic properties of sandstones using induced polarization and nuclear magnetic resonance for a joint permeability model

    NASA Astrophysics Data System (ADS)

    Osterman, G. K.; Keating, K.; Binley, A. M.; Slater, L. D.

    2015-12-01

    The permeability of sandstones can be modeled using the Katz and Thompson (KT) model which relates permeability to a characteristic hydraulic length scale, typically measured by mercury injection, and the electrically interconnected porosity. In situ estimation of these hydraulic parameters remains a challenge in hydrogeology; emerging geophysical technologies may help to solve this problem. Induced polarization (IP) and nuclear magnetic resonance (NMR) are two geophysical methods shown to be sensitive to physical properties of the pore space that control fluid flow, such as the pore size distribution. Using laboratory data collected on sandstone cores with a diverse range of properties, we demonstrate that our measured NMR parameters best predict the characteristic hydraulic length scale of the KT model, while the IP data can be used to improve estimates of the true formation factor. We incorporate these estimated hydraulic parameters into a KT model to derive an IP-NMR permeability model that compares favorably to permeability estimates from the KT model using mercury injection measurements. Furthermore, the resulting model uses parameters that are potentially measureable in the field; future work will focus on implementing the model at the field scale.

  3. Thermophysical property and pore structure evolution in stressed and non-stressed neutron irradiated IG-110 nuclear graphite

    SciTech Connect

    Snead, Lance L.; Contescu, C. I.; Byun, T. S.; Porter, W.

    2016-04-23

    The nuclear graphite, IG-110, was irradiated with and without a compressive load of 5 MPa at ~400 C up to 9.3x1025 n/m2 (E>0.1 MeV.) Following irradiation physical properties were studied to compare the effect of graphite irradiation on microstructure developed under compression and in stress-free condition. Properties included: dimensional change, thermal conductivity, dynamic modulus, and CTE. The effect of stress on open internal porosity was determined through nitrogen adsorption. The IG-110 graphite experienced irradiation-induced creep that is differentiated from irradiation-induced swelling. Irradiation under stress resulted in somewhat greater thermal conductivity and coefficient of thermal expansion. While a significant increase in dynamic modulus occurs, no differentiation between materials irradiated with and without compressive stress was observed. Nitrogen adsorption analysis suggests a difference in pore evolution in the 0.3-40 nm range for graphite irradiated with and without stress, but this evolution is seen to be a small contributor to the overall dimensional change.

  4. Thermophysical property and pore structure evolution in stressed and non-stressed neutron irradiated IG-110 nuclear graphite

    DOE PAGES

    Snead, Lance L.; Contescu, C. I.; Byun, T. S.; ...

    2016-04-23

    The nuclear graphite, IG-110, was irradiated with and without a compressive load of 5 MPa at ~400 C up to 9.3x1025 n/m2 (E>0.1 MeV.) Following irradiation physical properties were studied to compare the effect of graphite irradiation on microstructure developed under compression and in stress-free condition. Properties included: dimensional change, thermal conductivity, dynamic modulus, and CTE. The effect of stress on open internal porosity was determined through nitrogen adsorption. The IG-110 graphite experienced irradiation-induced creep that is differentiated from irradiation-induced swelling. Irradiation under stress resulted in somewhat greater thermal conductivity and coefficient of thermal expansion. While a significant increase inmore » dynamic modulus occurs, no differentiation between materials irradiated with and without compressive stress was observed. Nitrogen adsorption analysis suggests a difference in pore evolution in the 0.3-40 nm range for graphite irradiated with and without stress, but this evolution is seen to be a small contributor to the overall dimensional change.« less

  5. Nonaqueous magnetic nanoparticle suspensions with controlled particle size and nuclear magnetic resonance properties.

    PubMed

    Meledandri, Carla J; Stolarczyk, Jacek K; Ghosh, Swapankumar; Brougham, Dermot F

    2008-12-16

    We report the preparation of monodisperse maghemite (gamma-Fe2O3) nanoparticle suspensions in heptane, by thermal decomposition of iron(III) acetylacetonate in the presence of oleic acid and oleylamine surfactants. By varying the surfactant/Fe precursor mole ratio during synthesis, control was exerted both over the nanocrystal core size, in the range from 3 to 6 nm, and over the magnetic properties of the resulting nanoparticle dispersions. We report field-cycling 1H NMR relaxation analysis of the superparamagnetic relaxation rate enhancement of nonaqueous suspensions for the first time. This approach permits measurement of the relaxivity and provides information on the saturation magnetization and magnetic anisotropy energy of the suspended particles. The saturation magnetization was found to be in the expected range for maghemite particles of this size. The anisotropy energy was found to increase significantly with decreasing particle size, which we attribute to increased shape anisotropy. This study can be used as a guide for the synthesis of maghemite nanoparticles with selected magnetic properties for a given application.

  6. Damage dosimetry and embrittlement monitoring of nuclear pressure vessels in real time by magnetic properties measurement. Technical progress report for year 2, October 1, 1991--September 30, 1992

    SciTech Connect

    Stubbins, J.F.; Ougouag, A.M.; Williams, J.G.

    1992-07-01

    The objective of this project is to develop a technique for real-time monitoring of neutron dose and of the onset and progression of embrittlement in operating nuclear pressure vessels. The technique relies on the measurement of magnetic properties of steel and other magnetic materials which are extremely sensitive to radiation-induced properties changes. The approach being developed here is innovative and unique. It promises to be readily applicable to all existing and planned reactor structures. The significance of this program is that it addresses a major concern in the operation of existing nuclear pressure vessels. The development of microscopic defect clusters during irradiation in the nuclear pressure vessel beltline region leads to an increase in material yield strength and a concomitant decrease in ductility, or ability to absorb energy in fracture (i.e. fracture toughness). This decrease in fracture toughness is alarming since it may impair the ability of the pressure vessel to resist fracture during unusual loading situations.

  7. Properties of nuclear waste melts and glasses: Contact-refractory corrosion and vapor phase hydration

    NASA Astrophysics Data System (ADS)

    Lu, Xiaodong

    Control of refractory corrosion in waste glass melts and meeting vapor phase hydration test (VHT) requirement for Hanford low-activity waste (LAW) glass product are two critical issues among many technical challenges of nuclear waste vitrification. In this study, refractory corrosion was treated as a complex non-equilibrium, multi-component and multi-phase reactive transport process and studied both thermodynamically and kinetically. Dissolution tests of granular refractory materials into under-saturated melts coupled with crystallization tests from supersaturated melts were used to determine the possible equilibrium points. The test results show that spinet phase is the most stable phase of K-3 refractory. Solubility of glass-refractory interface material controls the long term refractory corrosion rate and protects refractory from further corrosion. Therefore, refractory corrosion rate can be possibly adjusted by controlling the underlying solubility of the interface material. A set of monolithic refractory corrosion and dissolution tests was carried out to study the kinetic effects of refractory porosity and glass melt viscosity, the two major kinetic factors associated with reactive transport process. The test results show that temperature and glass melt viscosity have intensive effects on refractory material dissolution rate. Fast closure of channels near the glass-refractory interface during corrosion reaction by fast transformation of solid solution to spinel and spinel re-crystallization helps stop further corrosion reaction. Glass composition can be "passivated" by engineering the formulation to maximizing the beneficial alteration process. For the study of VHT kinetics, data from simulated LAW glasses studied previously at Pacific Northwest National Laboratory and Vitreous State Laboratory was modeled based on Avrami equation and its variant, the so-called generalized Avrami equation for better modeling of the VHT data. The results show that the kinetics

  8. Quantification of Petrophysical Properties and Their Correlations with Nuclear Magnetic Resonance and Spectral Induced Polarization Responses in Carbonate

    NASA Astrophysics Data System (ADS)

    Zhang, F.; Zhang, C.

    2016-12-01

    Carbonate rocks are well known for their highly complex petrophysical behaviors due to their intrinsically heterogeneous pore geometry. This laboratory study focuses on integrating two geophysical methods: nuclear magnetic resonance (NMR) and spectral induced polarization (SIP) to determine porosity, pore size distribution, and permeability of various carbonate rock samples. Carbonate samples from Pennsylvanian and Mississippian reservoir are selected from four classes (mudstones, packstones, wackstones and grainstones), with distinct depositional fabrics and pore system. NMR measures the relaxation of hydrogen nuclei at pore scale, and SIP determines dielectric property of a sample and is sensitive to the interfacial properties at mineral-fluid. Samples were fully saturated for T2 relaxation and complex conductivity measurements. The permeability and porosity were also obtained from Klinkenberg K-air tests. Additionally, the results from thin section, mercury intrusion, and gas adsorption will be used to calibrate NMR and SIP datasets and further analyze the control of porosity, pore size distribution, and specific surface on NMR and SIP signals. Comparing T2 relaxation and complex conductivity with petrographic and analytical data on pore attributes, our results elucidate how porosity, pore size distribution, and permeability correlate in carbonate pore system. Porosity (phi)-permeability (K)-T2,ML plots illustrate the general distribution of samples' petrophysical properties. Clusters of four rock classes, as well as linear correlations between phi-K, and phi-T2 can be identified from these plots. Furthermore, variations of peak frequencies of phase changes in samples indicate that pore size distribution has the critical impact on SIP responses. As the first attempt to characterize carbonates with integrated NMR and SIP method, these results would help establish correlations among pore attributes, permeability and NMR/SIP responses, and provide reasonable

  9. Homometallic and Heterometallic Antiferromagnetic Rings: Magnetic Properties Studied by Nuclear Magnetic Resonance

    SciTech Connect

    Casadei, Cecilia

    2011-01-01

    The aim of the present thesis is to investigate the local magnetic properties of homometallic Cr8 antiferromagnetic (AFM) ring and the changes occurring by replacing one Cr3+ ion with diamagnetic Cd2+ (Cr7Cd) and with Ni2+ (Cr7Ni). In the heterometallic ring a redistribution of the local magnetic moment is expected in the low temperature ground state. We have investigated those changes by both 53Cr-NMR and 19F-NMR. We have determined the order of magnitude of the transferred hyperfine coupling constant 19F - M+ where M+ = Cr3+, Ni2+ in the different rings. This latter result gives useful information about the overlapping of the electronic wavefunctions involved in the coordinative bond.

  10. The influence of roughness on tribological properties of nuclear grade graphite

    NASA Astrophysics Data System (ADS)

    Xiaowei, Luo; Suyuan, Yu; Xuanyu, Sheng; Shuyan, He

    2006-03-01

    The influence of surface roughness on tribological properties of graphite IG-11 was investigated on a standard SRV tester. The experimental condition was selected as: 30 N normal load, room temperature and a 10 Hz frequency with different strokes. The experiments environments included helium and air. Five types of roughness were studied in the experiments. The experiments revealed that the surface roughness greatly affected the graphite friction behavior. When the friction surface was smooth, the friction coefficient was high because of intensive adhesion accompanied by many pits at the friction surface. When the friction surface was rough, the adhesion was very poor, but the wear was excessive and generated many graphite particles at the friction surface. These particles can separate the friction surfaces, which reduced the friction action between them. For very rough specimens, the friction coefficient decreased with sliding velocity at about 0.004 m/s and then increases gradually.

  11. Structure and mechanical properties of improved cast stainless steels for nuclear applications

    NASA Astrophysics Data System (ADS)

    Kenik, E. A.; Busby, J. T.; Gussev, M. N.; Maziasz, P. J.; Hoelzer, D. T.; Rowcliffe, A. F.; Vitek, J. M.

    2017-01-01

    Casting of stainless steels is a promising and cost saving way of directly producing large and complex structures, such a shield modules or divertors for the ITER. In the present work, a series of modified high-nitrogen cast stainless steels has been developed and characterized. The steels, based on the cast equivalent of the composition of 316 stainless steel, have increased N (0.14-0.36%) and Mn (2-5.1%) content; copper was added to one of the heats. Mechanical tests were conducted with non-irradiated and 0.7 dpa neutron irradiated specimens. It was established that alloying by nitrogen significantly improves the yield stress of non-irradiated steels and the deformation hardening rate. Manganese tended to decrease yield stress but increased radiation hardening. The role of copper on mechanical properties was negligibly small. Analysis of structure was conducted using SEM-EDS and the nature and compositions of the second phases and inclusions were analyzed in detail. No ferrite formation or significant precipitation were observed in the modified steels. It was shown that the modified steels, compared to reference material (commercial cast 316L steel), had better strength level, exhibit significantly reduced elemental inhomogeneity and only minor second phase formation.

  12. Effects of prehydrostatic loading on mechanical and physical properties of nuclear-grade graphites

    NASA Astrophysics Data System (ADS)

    Yoda, S.; Eto, M.; Ioka, I.

    1984-06-01

    The effects of prehydrostatic loading on mechanical and physical properties were examined for two isostatistically-molded graphites, grades IG-11 and Iso-20. The increase in loading levels caused the monotonic decrease in specimen volume of both graphites, the change of which was much larger in the case of IG-11 graphite than of Iso-20. The electrical resistivity increased continuously with an increase in prehydrostatic loading levels, where the effect was more pronounced for IG-11 than for Iso-20 graphite. The manner in which the Young's moduli of the two materials changed after prehydrostatic loading was clearly different from each other, i.e., for IG-11 it decreased continuously with increasing pressure, whereas it increased at small hydrostatic pressures and leveled off above 300 MPa for Iso-20. A clear difference was also observed for the flexural strength of both materials: Its continuous decrease was caused by prehydrostatic loading for IG-11 graphite, whereas for Iso-20 it remained at the original value up to 500 MPa and decreased abruptly above that pressure level. An explanation of these features was provided from the viewpoint that microcracks are induced by hydrostatic loading.

  13. Influence of the octupole mode on nuclear high-K isomeric properties

    NASA Astrophysics Data System (ADS)

    Minkov, Nikolay; Walker, Phil

    2014-05-01

    The influence of quadrupole-octupole deformations on the energy and magnetic properties of high-K isomeric states in even-even actinide (U, Pu, Cm, Fm, No), rare-earth (Nd, Sm and Gd), and superheavy (^{270}\\text{Ds}) nuclei is examined within a deformed shell model with pairing interaction. The neutron two-quasiparticle (2qp) isomeric energies and magnetic dipole moments are calculated over a wide range in the plane of quadrupole and octupole deformations. In most cases the magnetic moments exhibit a pronounced sensitivity to the octupole deformation. At the same time, the calculations outline three different groups of nuclei: with pronounced, shallow, and missing minima in the 2qp energy surfaces with respect to the octupole deformation. The result indicates regions of nuclei with octupole softness as well as with possible octupole deformation in the high-K isomeric states. These findings show the need for further theoretical analysis as well as of detailed experimental measurements of magnetic moments in heavy deformed nuclei.

  14. Structure and mechanical properties of improved cast stainless steels for nuclear applications

    SciTech Connect

    Kenik, Edward A.; Busby, Jeremy T.; Gussev, Maxim N.; Maziasz, Philip J.; Hoelzer, David T.; Rowcliffe, Arthur F.; Vitek, John M.

    2016-10-27

    Casting of stainless steels is a promising and cost saving way of directly producing large and complex structures, such a shield modules or divertors for the ITER. Here, a series of modified high-nitrogen cast steels has been developed and characterized. The steels, based on the cast equivalent of 316 composition, have increased N (0.14-0.36%) and Mn (2-5.1%) content; copper was added to one of the heats. Mechanical tests were conducted with non-irradiated and neutron irradiated specimens at 0.7 dpa. It was established that alloying by nitrogen significantly improves the yield stress of non-irradiated steels and the deformation hardening rate. Manganese tended to decrease yield stress, but increased radiation hardening. Furthermore, the role of copper on mechanical properties was negligibly small. Analysis of structure was conducted using SEM-EDS and the nature and compositions of the second phases and inclusions were analyzed in detail. We show that the modified steels, compared to reference material, exhibit significantly reduced elemental inhomogeneity and second phase formation.

  15. Structure and mechanical properties of improved cast stainless steels for nuclear applications

    DOE PAGES

    Kenik, Edward A.; Busby, Jeremy T.; Gussev, Maxim N.; ...

    2016-10-27

    Casting of stainless steels is a promising and cost saving way of directly producing large and complex structures, such a shield modules or divertors for the ITER. Here, a series of modified high-nitrogen cast steels has been developed and characterized. The steels, based on the cast equivalent of 316 composition, have increased N (0.14-0.36%) and Mn (2-5.1%) content; copper was added to one of the heats. Mechanical tests were conducted with non-irradiated and neutron irradiated specimens at 0.7 dpa. It was established that alloying by nitrogen significantly improves the yield stress of non-irradiated steels and the deformation hardening rate. Manganesemore » tended to decrease yield stress, but increased radiation hardening. Furthermore, the role of copper on mechanical properties was negligibly small. Analysis of structure was conducted using SEM-EDS and the nature and compositions of the second phases and inclusions were analyzed in detail. We show that the modified steels, compared to reference material, exhibit significantly reduced elemental inhomogeneity and second phase formation.« less

  16. Properties of Plutonium-Containing Colloids Released from Glass-Bonded Sodalite Nuclear Waste Form

    SciTech Connect

    Morss, L.R.; Mertz, C.J.; Kropf, A.J.; Holly, J.L.

    2004-10-11

    In glass-bonded sodalite, which is the ceramic waste form (CWF) to immobilize radioactive electrorefiner salt from spent metallic reactor fuel, uranium and plutonium are found as 20-50 nm (U,Pu)O{sub 2} particles encapsulated in glass near glass-sodalite phase boundaries. In order to determine whether the (U,Pu)O{sub 2} affects the durability of the CWF, and to determine release behavior of uranium and plutonium during CWF corrosion, tests were conducted to measure the release of matrix and radioactive elements from crushed CWF samples into water and the properties of released plutonium. Released colloids have been characterized by sequential filtration of test solutions followed by elemental analysis, dynamic light scattering, transmission electron microscopy (TEM), and X-ray absorption spectroscopy. This paper reports the composition, size, and agglomeration of these colloids. Significant amounts of colloidal, amorphous aluminosilicates and smaller amounts of colloidal crystalline (U,Pu)O{sub 2} were identified in test solutions. The normalized releases of uranium and plutonium were significantly less than the normalized releases of matrix elements.

  17. Comparative study of predictive FE methods for mechanical properties of nuclear composites

    NASA Astrophysics Data System (ADS)

    Ali, Joshim; Farooqi, Johar K.; Buckthorpe, Derek; Cheyne, Allister; Mummery, Paul

    2009-01-01

    Carbon fiber reinforced carbon (C/C) composites are candidate materials for plasma facing components in experimental fusion reactors such as: the ITER; the JT-60 - a Tokamak fusion test facility (JAEA); and for control rods in the next generation fission reactors. Therefore, determining their thermo-mechanical properties under irradiation is essential for safe design-cum-operation of future reactors. Development of reliable models which can predict such materials' behavior is of massive advantage against the conventional experimental verification which is hugely expensive and time-consuming. Three-dimensional finite element (FE) methods are used here for predicting Young's modulus of two woven C/C composites where tensile tests are performed for validation. Stress distribution results indicate that a novel image-based route for FE meshes compared to a unit cell approach gives stronger agreement with experimental data. The image-based approach captures true porosity as fine microstructural details are converted from X-ray tomographic data. In comparison, the unit cell model represents idealizations of composite architecture that ignores porosities.

  18. Thermal Properties of LiCl-KCl Molten Salt for Nuclear Waste Separation

    SciTech Connect

    Sridharan, Kumar; Allen, Todd; Anderson, Mark; Simpson, Mike

    2012-11-30

    This project addresses both practical and fundamental scientific issues of direct relevance to operational challenges of the molten LiCl-KCl salt pyrochemical process, while providing avenues for improvements in the process. In order to understand the effects of the continually changing composition of the molten salt bath during the process, the project team will systematically vary the concentrations of rare earth surrogate elements, lanthanum, cerium, praseodymium, and neodymium, which will be added to the molten LiCl-KCl salt. They will also perform a limited number of focused experiments by the dissolution of depleted uranium. All experiments will be performed at 500 deg C. The project consists of the following tasks. Researchers will measure density of the molten salts using an instrument specifically designed for this purpose, and will determine the melting points with a differential scanning calorimeter. Knowledge of these properties is essential for salt mass accounting and taking the necessary steps to prevent melt freezing. The team will use cyclic voltammetry studies to determine redox potentials of the rare earth cations, as well as their diffusion coefficients and activities in the molten LiCl-KCl salt. In addition, the team will perform anodic stripping voltammetry to determine the concentration of the rare earth elements and their solubilities, and to develop the scientific basis for an on-line diagnostic system for in situ monitoring of the cation species concentration (rare earths in this case). Solubility and activity of the cation species are critically important for the prediction of the salt's useful lifetime and disposal.

  19. Nuclear astrophysics

    SciTech Connect

    Penionzhkevich, Yu. E.

    2010-08-15

    The International Year of Astronomy 2009 (IYA2009) was declared by the 62nd General Assembly of the United Nations and was also endorsed by UNESCO. Investigations in the realms of particle and nuclear physicsmake a large contribution in the development of our ideas of the properties of the Universe. The present article discusses some problems of the evolution of the Universe, nucleosyntheses, and cosmochronology from the point of view of nuclear and particle physics. Processes occurring in the Universe are compared with the mechanisms of the production and decay of nuclei, as well as with the mechanisms of their interaction at high energies. Examples that demonstrate the potential of nuclearphysics methods for studying cosmic objects and the properties of the Universe are given. The results that come from investigations into nuclear reactions induced by beams of radioactive nuclei and which make it possible to take a fresh look at the nucleosynthesis scenario in the range at light nuclei are presented.

  20. Gordon Conference on Nuclear Research

    SciTech Connect

    Austin, S.M.

    1983-09-01

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

  1. Anomalous solute transport in saturated porous media: Relating transport model parameters to electrical and nuclear magnetic resonance properties

    NASA Astrophysics Data System (ADS)

    Swanson, Ryan D.; Binley, Andrew; Keating, Kristina; France, Samantha; Osterman, Gordon; Day-Lewis, Frederick D.; Singha, Kamini

    2015-02-01

    The advection-dispersion equation (ADE) fails to describe commonly observed non-Fickian solute transport in saturated porous media, necessitating the use of other models such as the dual-domain mass-transfer (DDMT) model. DDMT model parameters are commonly calibrated via curve fitting, providing little insight into the relation between effective parameters and physical properties of the medium. There is a clear need for material characterization techniques that can provide insight into the geometry and connectedness of pore spaces related to transport model parameters. Here, we consider proton nuclear magnetic resonance (NMR), direct-current (DC) resistivity, and complex conductivity (CC) measurements for this purpose, and assess these methods using glass beads as a control and two different samples of the zeolite clinoptilolite, a material that demonstrates non-Fickian transport due to intragranular porosity. We estimate DDMT parameters via calibration of a transport model to column-scale solute tracer tests, and compare NMR, DC resistivity, CC results, which reveal that grain size alone does not control transport properties and measured geophysical parameters; rather, volume and arrangement of the pore space play important roles. NMR cannot provide estimates of more-mobile and less-mobile pore volumes in the absence of tracer tests because these estimates depend critically on the selection of a material-dependent and flow-dependent cutoff time. Increased electrical connectedness from DC resistivity measurements are associated with greater mobile pore space determined from transport model calibration. CC was hypothesized to be related to length scales of mass transfer, but the CC response is unrelated to DDMT.

  2. Conserved cell cycle regulatory properties within the amino terminal domain of the Epstein-Barr virus nuclear antigen 3C

    SciTech Connect

    Sharma, Nikhil; Knight, Jason S.; Robertson, Erle S. . E-mail: erle@mail.med.upenn.edu

    2006-03-15

    The gammaherpesviruses Rhesus lymphocryptovirus (LCV) and Epstein-Barr virus (EBV) are closely related phylogenetically. Rhesus LCV efficiently immortalizes Rhesus B cells in vitro. However, despite a high degree of conservation between the Rhesus LCV and EBV genomes, Rhesus LCV fails to immortalize human B cells in vitro. This species restriction may, at least in part, be linked to the EBV nuclear antigens (EBNAs) and latent membrane proteins (LMPs), known to be essential for B cell transformation. We compared specific properties of EBNA3C, a well-characterized and essential EBV protein, with its Rhesus counterpart to determine whether EBNA3C phenotypes which contribute to cell cycle regulation are conserved in the Rhesus LCV. We show that both EBNA3C and Rhesus EBNA3C bind to a conserved region of mammalian cyclins, regulate pRb stability, and modulate SCF{sup Skp2}-dependent ubiquitination. These results suggest that Rhesus LCV restriction from human B cell immortalization is independent of the conserved cell cycle regulatory functions of the EBNA3C protein.

  3. Properties of K,Rb-intercalated C60 encapsulated inside carbon nanotubes called peapods derived from nuclear magnetic resonance

    NASA Astrophysics Data System (ADS)

    Mahfouz, R.; Bouhrara, M.; Kim, Y.; Wâgberg, T.; Goze-Bac, C.; Abou-Hamad, E.

    2015-09-01

    We present a detailed experimental study on how magnetic and electronic properties of Rb,K-intercalated C60 encapsulated inside carbon nanotubes called peapods can be derived from 13C nuclear magnetic resonance investigations. Ring currents do play a basic role in those systems; in particular, the inner cavities of nanotubes offer an ideal environment to investigate the magnetism at the nanoscale. We report the largest diamagnetic shifts down to -68.3 ppm ever observed in carbon allotropes, which is connected to the enhancement of the aromaticity of the nanotube envelope upon intercalation. The metallization of intercalated peapods is evidenced from the chemical shift anisotropy and spin-lattice relaxation (T1) measurements. The observed relaxation curves signal a three-component model with two slow and one fast relaxing components. We assigned the fast component to the unpaired electrons charged C60 that show a phase transition near 100 K. The two slow components can be rationalized by the two types of charged C60 at two different positions with a linear regime following Korringa behavior, which is typical for metallic system and allow us to estimate the density of sate at Fermi level n(EF).

  4. Nuclear quadrupole double resonance spectrometer with magnetic property measurement system direct current superconducting quantum interference device detector and automatic tuning.

    PubMed

    Shroyer, Mark H; Day, Edmund P

    2011-05-01

    A new nuclear quadrupole double resonance spectrometer based on a commercial superconducting quantum interference device (SQUID) setup (a Magnetic Property Measurement System (MPMS) from Quantum Design) is described. The experiment involves the indirect detection of pure quadrupole resonances (PQR) of a dilute spin system via the direct SQUID detected NMR of an abundant spin system. The experiment is conducted at low (3-20 K) temperatures and the magnetic field is cycled between a high (5.5 T) polarizing field, to an intermediate (0.1 T) detection field, to zero field where the sample is irradiated with a modulated search RF and back to the detection field. Loss of the NMR signal indicates the detection of a PQR. The RF circuit used for both the NMR and zero field irradiation is digitally controlled. Use of the External Device Control allows for the complete automation of the system. Test measurements on diphenyl ether are in good agreement with previously reported results. Pure (17)O quadrupole resonances were detected for spin systems with concentrations as low as 120 μM.

  5. The nuclear dynamo; Can a nuclear tornado annihilate nations

    SciTech Connect

    McNally, J.R. Jr.

    1991-01-01

    This paper reports on the development of the hypothesis of a nuclear dynamo for a controlled nuclear fusion reactor. This dynamo hypothesis suggests properties for a nuclear tornado that could annihilate nations if accidentally triggered by a single high yield to weight nuclear weapon detonation. The formerly classified reports on ignition of the atmosphere, the properties of a nuclear dynamo, methods to achieve a nuclear dynamo in the laboratory, and the analogy of a nuclear dynamo to a nuclear tornado are discussed. An unclassified international study of this question is urged.

  6. Investigating the binding properties of porous drug delivery systems using nuclear sensors (radiotracers) and positron annihilation lifetime spectroscopy--predicting conditions for optimum performance.

    PubMed

    Mume, Eskender; Lynch, Daniel E; Uedono, Akira; Smith, Suzanne V

    2011-06-21

    Understanding how the size, charge and number of available pores in porous material influences the uptake and release properties is important for optimising their design and ultimately their application. Unfortunately there are no standard methods for screening porous materials in solution and therefore formulations must be developed for each encapsulated agent. This study investigates the potential of a library of radiotracers (nuclear sensors) for assessing the binding properties of hollow silica shell materials. Uptake and release of Cu(2+) and Co(2+) and their respective complexes with polyazacarboxylate macrocycles (dota and teta) and a series of hexa aza cages (diamsar, sarar and bis-(p-aminobenzyl)-diamsar) from the hollow silica shells was monitored using their radioisotopic analogues. Coordination chemistry of the metal (M) species, subtle alterations in the molecular architecture of ligands (Ligand) and their resultant complexes (M-Ligand) were found to significantly influence their uptake over pH 3 to 9 at room temperature. Positively charged species were selectively and rapidly (within 10 min) absorbed at pH 7 to 9. Negatively charged species were preferentially absorbed at low pH (3 to 5). Rates of release varied for each nuclear sensor, and time to establish equilibrium varied from minutes to days. The subtle changes in design of the nuclear sensors proved to be a valuable tool for determining the binding properties of porous materials. The data support the development of a library of nuclear sensors for screening porous materials for use in optimising the design of porous materials and the potential of nuclear sensors for high through-put screening of materials.

  7. Integrin α4β1 controls G9a activity that regulates epigenetic changes and nuclear properties required for lymphocyte migration

    PubMed Central

    Zhang, Xiaohong; Cook, Peter C.; Zindy, Egor; Williams, Craig J.; Jowitt, Thomas A.; Streuli, Charles H.; MacDonald, Andrew S.; Redondo-Muñoz, Javier

    2016-01-01

    The mechanical properties of the cell nucleus change to allow cells to migrate, but how chromatin modifications contribute to nuclear deformability has not been defined. Here, we demonstrate that a major factor in this process involves epigenetic changes that underpin nuclear structure. We investigated the link between cell adhesion and epigenetic changes in T-cells, and demonstrate that T-cell adhesion to VCAM1 via α4β1 integrin drives histone H3 methylation (H3K9me2/3) through the methyltransferase G9a. In this process, active G9a is recruited to the nuclear envelope and interacts with lamin B1 during T-cell adhesion through α4β1 integrin. G9a activity not only reorganises the chromatin structure in T-cells, but also affects the stiffness and viscoelastic properties of the nucleus. Moreover, we further demonstrated that these epigenetic changes were linked to lymphocyte movement, as depletion or inhibition of G9a blocks T-cell migration in both 2D and 3D environments. Thus, our results identify a novel mechanism in T-cells by which α4β1 integrin signaling drives specific chromatin modifications, which alter the physical properties of the nucleus and thereby enable T-cell migration. PMID:26657637

  8. Differentially expressed nuclear proteins in human CCRF-CEM, HL-60, MEC-1 and Raji cells correlate with cellular properties.

    PubMed

    Henrich, Silke; Crossett, Ben; Christopherson, Richard I

    2007-10-01

    The human cell lines CCRF-CEM (T-cell acute lymphocytic leukemia), HL-60 (acute myeloid leukemia), MEC-1 (B-cell chronic lymphocytic leukemia) and Raji (Burkitt's B-cell lymphoma) have been analysed for differences in their nuclear proteomes. Using 2-D DIGE, 55 nuclear proteins have been identified that are differentially expressed (p<0.025) between the four cell lines, including proteins associated with transcription, proliferation, DNA repair and apoptosis. Of these 55 proteins, 22 were over-expressed in just one cell line, and four were down-regulated in one cell line. Proteins uniquely over-expressed between myeloid and lymphoid cell lines include those that may have use as markers for diagnosis, disease progression and B-cell maturation and differentiation. Expression of various proliferation-associated nuclear proteins correlated with relative growth rates of the cell lines, giving these proteins potential diagnostic applications for distinction of chronic versus acute subtypes of haematological malignancies. Identification of these differentially expressed nuclear proteins should facilitate elucidation of the molecular mechanisms underlying leukocyte differentiation and transformation to leukemias and lymphomas. The nuclear expression profiles should enable classification of subtypes of leukemia, and identify potential nuclear protein targets for development of diagnostic and therapeutic strategies.

  9. Complete genome sequence and integrated protein localization and interaction map for alfalfa dwarf virus, which combines properties of both cytoplasmic and nuclear plant rhabdoviruses

    SciTech Connect

    Bejerman, Nicolás; Giolitti, Fabián; Breuil, Soledad de; Trucco, Verónica; Nome, Claudia; Lenardon, Sergio; Dietzgen, Ralf G.

    2015-09-15

    Summary: We have determined the full-length 14,491-nucleotide genome sequence of a new plant rhabdovirus, alfalfa dwarf virus (ADV). Seven open reading frames (ORFs) were identified in the antigenomic orientation of the negative-sense, single-stranded viral RNA, in the order 3′-N-P-P3-M-G-P6-L-5′. The ORFs are separated by conserved intergenic regions and the genome coding region is flanked by complementary 3′ leader and 5′ trailer sequences. Phylogenetic analysis of the nucleoprotein amino acid sequence indicated that this alfalfa-infecting rhabdovirus is related to viruses in the genus Cytorhabdovirus. When transiently expressed as GFP fusions in Nicotiana benthamiana leaves, most ADV proteins accumulated in the cell periphery, but unexpectedly P protein was localized exclusively in the nucleus. ADV P protein was shown to have a homotypic, and heterotypic nuclear interactions with N, P3 and M proteins by bimolecular fluorescence complementation. ADV appears unique in that it combines properties of both cytoplasmic and nuclear plant rhabdoviruses. - Highlights: • The complete genome of alfalfa dwarf virus is obtained. • An integrated localization and interaction map for ADV is determined. • ADV has a genome sequence similarity and evolutionary links with cytorhabdoviruses. • ADV protein localization and interaction data show an association with the nucleus. • ADV combines properties of both cytoplasmic and nuclear plant rhabdoviruses.

  10. Nuclear Models

    NASA Astrophysics Data System (ADS)

    Fossión, Rubén

    2010-09-01

    The atomic nucleus is a typical example of a many-body problem. On the one hand, the number of nucleons (protons and neutrons) that constitute the nucleus is too large to allow for exact calculations. On the other hand, the number of constituent particles is too small for the individual nuclear excitation states to be explained by statistical methods. Another problem, particular for the atomic nucleus, is that the nucleon-nucleon (n-n) interaction is not one of the fundamental forces of Nature, and is hard to put in a single closed equation. The nucleon-nucleon interaction also behaves differently between two free nucleons (bare interaction) and between two nucleons in the nuclear medium (dressed interaction). Because of the above reasons, specific nuclear many-body models have been devised of which each one sheds light on some selected aspects of nuclear structure. Only combining the viewpoints of different models, a global insight of the atomic nucleus can be gained. In this chapter, we revise the the Nuclear Shell Model as an example of the microscopic approach, and the Collective Model as an example of the geometric approach. Finally, we study the statistical properties of nuclear spectra, basing on symmetry principles, to find out whether there is quantum chaos in the atomic nucleus. All three major approaches have been rewarded with the Nobel Prize of Physics. In the text, we will stress how each approach introduces its own series of approximations to reduce the prohibitingly large number of degrees of freedom of the full many-body problem to a smaller manageable number of effective degrees of freedom.

  11. Nuclear Models

    SciTech Connect

    Fossion, Ruben

    2010-09-10

    The atomic nucleus is a typical example of a many-body problem. On the one hand, the number of nucleons (protons and neutrons) that constitute the nucleus is too large to allow for exact calculations. On the other hand, the number of constituent particles is too small for the individual nuclear excitation states to be explained by statistical methods. Another problem, particular for the atomic nucleus, is that the nucleon-nucleon (n-n) interaction is not one of the fundamental forces of Nature, and is hard to put in a single closed equation. The nucleon-nucleon interaction also behaves differently between two free nucleons (bare interaction) and between two nucleons in the nuclear medium (dressed interaction).Because of the above reasons, specific nuclear many-body models have been devised of which each one sheds light on some selected aspects of nuclear structure. Only combining the viewpoints of different models, a global insight of the atomic nucleus can be gained. In this chapter, we revise the the Nuclear Shell Model as an example of the microscopic approach, and the Collective Model as an example of the geometric approach. Finally, we study the statistical properties of nuclear spectra, basing on symmetry principles, to find out whether there is quantum chaos in the atomic nucleus. All three major approaches have been rewarded with the Nobel Prize of Physics. In the text, we will stress how each approach introduces its own series of approximations to reduce the prohibitingly large number of degrees of freedom of the full many-body problem to a smaller manageable number of effective degrees of freedom.

  12. Bench Marking Accuracies of Variational Methods for Studying Molecular and Solid State Properties by Application to Nuclear Quadrupole Interactions in Boron and Aluminum Atoms

    NASA Astrophysics Data System (ADS)

    Pink, R. H.; Dubey, Archan; Badu, S. R.; Scheicher, R. H.; Chow, Lee; Das, T. P.

    2011-03-01

    As part of a test of the accuracy of the variational methods (VHFMBPT) and (VDFT) for energy and wave-function dependent properties in molecular and solid state systems, the nuclear quadrupole interactions in the ground state of boron and aluminum atoms are being studied by these methods. Results for the electric field gradients will be presented for these atoms and compared with experiment , and with results , of the highly accurate LCMBPT procedure for the atoms. Conclusions about the factors governing the accuracies of the variational methods will be presented. J.S.M. Harvey, L. Evans, and H. Lew, Can. J. Phys. 50, 1719 (1972)

  13. Calculation of binary magnetic properties and potential energy curve in xenon dimer: second virial coefficient of (129)Xe nuclear shielding.

    PubMed

    Hanni, Matti; Lantto, Perttu; Runeberg, Nino; Jokisaari, Jukka; Vaara, Juha

    2004-09-22

    Quantum chemical calculations of the nuclear shielding tensor, the nuclear quadrupole coupling tensor, and the spin-rotation tensor are reported for the Xe dimer using ab initio quantum chemical methods. The binary chemical shift delta, the anisotropy of the shielding tensor Delta sigma, the nuclear quadrupole coupling tensor component along the internuclear axis chi( parallel ), and the spin-rotation constant C( perpendicular ) are presented as a function of internuclear distance. The basis set superposition error is approximately corrected for by using the counterpoise correction (CP) method. Electron correlation effects are systematically studied via the Hartree-Fock, complete active space self-consistent field, second-order Møller-Plesset many-body perturbation, and coupled-cluster singles and doubles (CCSD) theories, the last one without and with noniterative triples, at the nonrelativistic all-electron level. We also report a high-quality theoretical interatomic potential for the Xe dimer, gained using the relativistic effective potential/core polarization potential scheme. These calculations used valence basis set of cc-pVQZ quality supplemented with a set of midbond functions. The second virial coefficient of Xe nuclear shielding, which is probably the experimentally best-characterized intermolecular interaction effect in nuclear magnetic resonance spectroscopy, is computed as a function of temperature, and compared to experiment and earlier theoretical results. The best results for the second virial coefficient, obtained using the CCSD(CP) binary chemical shift curve and either our best theoretical potential or the empirical potentials from the literature, are in good agreement with experiment. Zero-point vibrational corrections of delta, Delta sigma, chi (parallel), and C (perpendicular) in the nu=0, J=0 rovibrational ground state of the xenon dimer are also reported.

  14. Differences in rates of decrease of environmental radiation dose rates by ground surface property in Fukushima City after the Fukushima Daiichi nuclear power plant accident.

    PubMed

    Kakamu, Takeyasu; Kanda, Hideyuki; Tsuji, Masayoshi; Kobayashi, Daisuke; Miyake, Masao; Hayakawa, Takehito; Katsuda, Shin-ichiro; Mori, Yayoi; Okouchi, Toshiyasu; Hazama, Akihiro; Fukushima, Tetsuhito

    2013-01-01

    After the Great East Japan Earthquake on 11 March 2011, the environmental radiation dose in Fukushima City increased. On 11 April, 1 mo after the earthquake, the environmental radiation dose rate at various surfaces in the same area differed greatly by surface property. Environmental radiation measurements continue in order to determine the estimated time to 50% reduction in environmental radiation dose rates by surface property in order to make suggestions for decontamination in Fukushima. The measurements were carried out from 11 April to 11 November 2011. Forty-eight (48) measurement points were selected, including four kinds of ground surface properties: grass (13), soil (5), artificial turf (7), and asphalt (23). Environmental radiation dose rate was measured at heights of 100 cm above the ground surface. Time to 50% reduction of environmental radiation dose rates was estimated for each ground surface property. Radiation dose rates on 11 November had decreased significantly compared with those on 11 April for all surface properties. Artificial turf showed the longest time to 50% reduction (544.32 d, standard error: 96.86), and soil showed the shortest (213.20 d, standard error: 35.88). The authors found the environmental radiation dose rate on artificial materials to have a longer 50% reduction time than that on natural materials. These results contribute to determining an order of priority for decontamination after nuclear disasters.

  15. Nuclear Wallet Cards from the National Nuclear Data Center (NNDC)

    DOE Data Explorer

    Tuli, Jagdish K.

    Nuclear Wallet Cards present properties for ground and isomeric states of all known nuclides. Properties given are: spin and parity assignments, nuclear mass excesses, half-life, isotopic abundances, and decay modes. Appendices contain properties of elements, fundamental constants and other useful information. Nuclear Wallet Cards booklet is published by the National Nuclear Data Center and its electronic (current) version is periodically updated. The Nuclear Wallet Cards by Dr. Jagdish K. Tuli, presently in its 8th edition, is distributed in print as well as in PDA-adaptable Palm Pilot format; the data table as an ASCII file is available upon request. [Taken from http://www.nndc.bnl.gov/wallet/

  16. Changes in the thermal properties of PADC film-based nuclear track detectors produced by high doses of γ-radiation

    NASA Astrophysics Data System (ADS)

    Saad, A. F.; Saad, Noura; Abdalla, Y. K.

    2014-04-01

    Irradiation effects on the thermal properties of poly allyl diglycol carbonate (PADC) polymer-based nuclear track detectors (in the form of CR-39) have been investigated. PADC films were exposed to γ-rays at high doses ranging from 5.0 × 105 to 1.0 × 106 Gy. The induced modifications were analyzed by means of thermogravimetric analysis, which indicated that the PADC film decomposed in three main stages. The activation energy for thermal decomposition was determined using a type of Arrhenius equation based on the TGA experimental results. This study presents quantitative results showing that the exposed PADC films do not undergo continual further degradation from high-energy γ-photons with increase in dose. The experimental results also provide insight into the specific property changes induced by γ-rays, which may be of use for industrial applications.

  17. Microscopic properties of the heavy-fermion superconductor PuCoIn5 explored by nuclear quadrupole resonance

    NASA Astrophysics Data System (ADS)

    Koutroulakis, G.; Yasuoka, H.; Chudo, H.; Tobash, P. H.; Mitchell, J. N.; Bauer, E. D.; Thompson, J. D.

    2014-05-01

    We report 115In nuclear quadrupolar resonance (NQR) measurements on the heavy-fermion superconductor PuCoIn5, in the temperature range 0.29K ≤ T ≤ 75K. The NQR parameters for the two crystallographically inequivalent In sites are determined, and their temperature dependence is investigated. A linear shift of the quadrupolar frequency with lowering temperature below the critical value Tc is revealed, in agreement with the prediction for composite pairing. The nuclear spin-lattice relaxation rate T1-1(T) clearly signals a superconducting (SC) phase transition at Tc ≃ 2.3 K, with strong spin fluctuations, mostly in-plane, dominating the relaxation process in the normal state near to Tc. Analysis of the T1-1 data in the SC state suggests that PuCoIn5 is a strong-coupling d-wave superconductor.

  18. A study on nuclear properties of Zr, Nb, and Ta nuclei used as structural material in fusion reactor

    NASA Astrophysics Data System (ADS)

    Sahan, Halide; Tel, Eyyup; Sahan, Muhittin; Aydin, Abdullah; Hakki Sarpun, Ismail; Kara, Ayhan; Doner, Mesut

    2015-07-01

    Fusion has a practically limitless fuel supply and is attractive as an energy source. The main goal of fusion research is to construct and operate an energy generating system. Fusion researches also contains fusion structural materials used fusion reactors. Material issues are very important for development of fusion reactors. Therefore, a wide range of fusion structural materials have been considered for fusion energy applications. Zirconium (Zr), Niobium (Nb) and Tantalum (Ta) containing alloys are important structural materials for fusion reactors and many other fields. Naturally Zr includes the 90Zr (%51.5), 91Zr (%11.2), 92Zr (%17.1), 94Zr (%17.4), 96Zr (%2.80) isotopes and 93Nb and 181Ta include the 93Nb (%100) and 181Ta (%99.98), respectively. In this study, the charge, mass, proton and neutron densities and the root-mean-square (rms) charge radii, rms nuclear mass radii, rms nuclear proton, and neutron radii have been calculated for 87-102Zr, 93Nb, 181Ta target nuclei isotopes by using the Hartree-Fock method with an effective Skyrme force with SKM*. The calculated results have been compared with those of the compiled experimental taken from Atomic Data and Nuclear Data Tables and theoretical values of other studies.

  19. Nuclear power and nuclear weapons

    SciTech Connect

    Vaughen, V.C.A.

    1983-01-01

    The proliferation of nuclear weapons and the expanded use of nuclear energy for the production of electricity and other peaceful uses are compared. The difference in technologies associated with nuclear weapons and nuclear power plants are described.

  20. Magnetic and superconducting properties of a heavy-fermion CeCoIn5 epitaxial film probed by nuclear quadrupole resonance

    NASA Astrophysics Data System (ADS)

    Yamanaka, Takayoshi; Shimozawa, Masaaki; Shishido, Hiroaki; Kitagawa, Shunsaku; Ikeda, Hiroaki; Shibauchi, Takasada; Terashima, Takahito; Matsuda, Yuji; Ishida, Kenji

    2017-08-01

    Since the progress in the fabrication techniques of thin films of exotic materials such as strongly correlated heavy-fermion compounds, microscopic studies of the magnetic and electronic properties inside the films have been needed. Herein, we report the observation of 115In nuclear quadrupole resonance (NQR) in an epitaxial film of the heavy-fermion superconductor CeCoIn5, for which the microscopic field gradient within the unit cell as well as magnetic and superconducting properties at zero field are evaluated. We find that the nuclear spin-lattice relaxation rate in the film is in excellent agreement with that of bulk crystals, whereas the NQR spectra show noticeable shifts and significant broadening indicating a change in the electric-field distribution inside the film. The analysis implies a displacement of In layers in the film, which, however, does not affect the magnetic fluctuations and superconducting pairing. This implies that inhomogeneity of the electronic field gradient in the film sample causes no pair-breaking effect.

  1. Towards novel efficient and stable nuclear import signals: synthesis and properties of trimethylguanosine cap analogs modified within the 5',5'-triphosphate bridge.

    PubMed

    Zytek, Malgorzata; Kowalska, Joanna; Lukaszewicz, Maciej; Wojtczak, Blazej A; Zuberek, Joanna; Ferenc-Mrozek, Aleksandra; Darzynkiewicz, Edward; Niedzwiecka, Anna; Jemielity, Jacek

    2014-12-07

    A trimethylguanosine (TMG) cap is present at the 5' end of several small nuclear and nucleolar RNAs. Recently, it has been reported that the TMG cap is a potential nuclear import signal for nucleus-targeting therapeutic nucleic acids and proteins. The import is mediated by recognition of the TMG cap by the snRNA transporting protein, snurportin1. This work describes the synthesis and properties of a series of dinucleotide TMG cap (m3(2,2,7)GpppG) analogs modified in the 5',5'-triphosphate bridge as tools to study TMG cap-dependent biological processes. The bridge was altered at different positions by introducing either bridging (imidodiphosphate, O to NH and methylenebisphosphonate, O to CH2) or non-bridging (phosphorothioate, O to S and boranophosphate, O to BH3) modifications, or by elongation to tetraphosphate. The stability of novel analogs in blood serum was studied to reveal that the α,β-bridging O to NH substitution (m3(2,2,7)GppNHpG) confers the highest resistance. Short RNAs capped with analogs containing α,β-bridging (m3(2,2,7)GppNHpG) or β-non-bridging (m3(2,2,7)GppSpG D2) modifications were resistant to decapping pyrophosphatase, hNudt16. Preliminary studies on binding by human snurportin1 revealed that both O to NH and O to S substitutions support this binding. Due to favorable properties in all three assays, m3(2,2,7)GppNHpG was selected as a promising candidate for further studies on the efficiency of the TMG cap as a nuclear import signal.

  2. Nuclear exoticism

    NASA Astrophysics Data System (ADS)

    Penionzhkevich, Yu. E.

    2016-07-01

    Extreme states of nuclearmatter (such that feature high spins, large deformations, high density and temperature, or a large excess of neutrons and protons) play an important role in studying fundamental properties of nuclei and are helpful in solving the problem of constructing the equation of state for nuclear matter. The synthesis of neutron-rich nuclei near the nucleon drip lines and investigation of their properties permit drawing conclusions about the positions of these boundaries and deducing information about unusual states of such nuclei and about their decays. At the present time, experimental investigations along these lines can only be performed via the cooperation of leading research centers that possess powerful heavy-ion accelerators, such as the Large Hadron Collider (LHC) at CERN and the heavy-ion cyclotrons at the Joint Institute for Nuclear Research (JINR, Dubna), where respective experiments are being conducted by physicists from about 20 JINR member countries. The present article gives a survey of the most recent results in the realms of super neutron-rich nuclei. Implications of the change in the structure of such nuclei near the nucleon drip lines are discussed. Information about the results obtained by measuring the masses (binding energies) of exotic nuclei, the nucleon-distribution radii (neutron halo) and momentum distributions in them, and their deformations and quantum properties is presented. It is shown that the properties of nuclei lying near the stability boundaries differ strongly from the properties of other nuclei. The problem of the stability of nuclei that is associated with the magic numbers of 20 and 28 is discussed along with the effect of new magic numbers.

  3. Nuclear exoticism

    SciTech Connect

    Penionzhkevich, Yu. E.

    2016-07-15

    Extreme states of nuclearmatter (such that feature high spins, large deformations, high density and temperature, or a large excess of neutrons and protons) play an important role in studying fundamental properties of nuclei and are helpful in solving the problem of constructing the equation of state for nuclear matter. The synthesis of neutron-rich nuclei near the nucleon drip lines and investigation of their properties permit drawing conclusions about the positions of these boundaries and deducing information about unusual states of such nuclei and about their decays. At the present time, experimental investigations along these lines can only be performed via the cooperation of leading research centers that possess powerful heavy-ion accelerators, such as the Large Hadron Collider (LHC) at CERN and the heavy-ion cyclotrons at the Joint Institute for Nuclear Research (JINR, Dubna), where respective experiments are being conducted by physicists from about 20 JINR member countries. The present article gives a survey of the most recent results in the realms of super neutron-rich nuclei. Implications of the change in the structure of such nuclei near the nucleon drip lines are discussed. Information about the results obtained by measuring the masses (binding energies) of exotic nuclei, the nucleon-distribution radii (neutron halo) and momentum distributions in them, and their deformations and quantum properties is presented. It is shown that the properties of nuclei lying near the stability boundaries differ strongly from the properties of other nuclei. The problem of the stability of nuclei that is associated with the magic numbers of 20 and 28 is discussed along with the effect of new magic numbers.

  4. Nuclear rights - nuclear wrongs

    SciTech Connect

    Paul, E.F.; Miller, F.D.; Paul, J.; Ahrens, J.

    1986-01-01

    This book contains 11 selections. The titles are: Three Ways to Kill Innocent Bystanders: Some Conundrums Concerning the Morality of War; The International Defense of Liberty; Two Concepts of Deterrence; Nuclear Deterrence and Arms Control; Ethical Issues for the 1980s; The Moral Status of Nuclear Deterrent Threats; Optimal Deterrence; Morality and Paradoxical Deterrence; Immoral Risks: A Deontological Critique of Nuclear Deterrence; No War Without Dictatorship, No Peace Without Democracy: Foreign Policy as Domestic Politics; Marxism-Leninism and its Strategic Implications for the United States; Tocqueveille War.

  5. NUCLEAR REACTORS

    DOEpatents

    Long, E.; Ashley, J.W.

    1958-12-16

    A graphite moderator structure is described for a gas-cooled nuclear reactor having a vertical orlentation wherein the structure is physically stable with regard to dlmensional changes due to Wigner growth properties of the graphite, and leakage of coolant gas along spaces in the structure is reduced. The structure is comprised of stacks of unlform right prismatic graphite blocks positioned in layers extending in the direction of the lengths of the blocks, the adjacent end faces of the blocks being separated by pairs of tiles. The blocks and tiles have central bores which are in alignment when assembled and are provided with cooperatlng keys and keyways for physical stability.

  6. Nuclear physics and cosmology

    SciTech Connect

    Coc, Alain

    2014-05-09

    There are important aspects of Cosmology, the scientific study of the large scale properties of the universe as a whole, for which nuclear physics can provide insights. Here, we will focus on Standard Big-Bang Nucleosynthesis and we refer to the previous edition of the School [1] for the aspects concerning the variations of constants in nuclear cosmo-physics.

  7. Molecular analysis of elastic properties of the stratum corneum by solid-state 13C-nuclear magnetic resonance spectroscopy.

    PubMed

    Jokura, Y; Ishikawa, S; Tokuda, H; Imokawa, G

    1995-05-01

    To elucidate the precise molecular mechanisms underlying stratum corneum (SC) elasticity, we investigated the molecular dynamics of chemical residues within keratin fibers of human plantar SC under various conditions by cross polarization/magic angle spinning 13C-nuclear magnetic resonance. The intensities of nuclear magnetic resonance spectra responsible for amide carbonyl, C alpha methine, and side-chain aliphatic carbons in the intact SC decreased markedly with increasing water content of up to 30% in dry SC, and then remained constant at greater than 30%. Lipid extraction of intact SC with acetone/ether (1:1) did not induce any significant change in the nuclear magnetic resonance spectrum, whereas additional treatment with water, which released natural moisturizing factors (mainly amino acids), caused the SC to lose elasticity. The observed decrease in elasticity of the SC recovered after treatment with basic and neutral amino acids, but not after treatment with acidic amino acid. With the latter treatment, movement of amino acid molecules was significantly disturbed, suggesting a strong interaction with keratin fibers. Parallel studies of the complex elastic modulus of a pig SC sheet with a rheovibron also demonstrated that removal of natural moisturizing factor reduced the elasticity of the SC; this effect was also reversed by the application of basic and neutral amino acids, but not by the application of acidic amino acid. These findings suggest that structural keratin proteins, mainly consisting of 10-nm filaments, acquire their elasticity with the help of hydrated natural moisturizing factor via the reduction of intermolecular forces, probably through nonhelical regions between keratin fibers.

  8. Thermodynamics of neutron-rich nuclear matter

    SciTech Connect

    López, Jorge A.; Porras, Sergio Terrazas Gutiérrez, Araceli Rodríguez

    2016-07-07

    This manuscript presents methods to obtain properties of neutron-rich nuclear matter from classical molecular dynamics. Some of these are bulk properties of infinite nuclear matter, phase information, the Maxwell construction, spinodal lines and symmetry energy.

  9. Quantum nuclear pasta and nuclear symmetry energy

    NASA Astrophysics Data System (ADS)

    Fattoyev, F. J.; Horowitz, C. J.; Schuetrumpf, B.

    2017-05-01

    Complex and exotic nuclear geometries, collectively referred to as "nuclear pasta," are expected to appear naturally in dense nuclear matter found in the crusts of neutron stars and supernovae environments. The pasta geometries depend on the average baryon density, proton fraction, and temperature and are critically important in the determination of many transport properties of matter in supernovae and the crusts of neutron stars. Using a set of self-consistent microscopic nuclear energy density functionals, we present the first results of large scale quantum simulations of pasta phases at baryon densities 0.03 ≤ρ ≤0.10 fm-3 , proton fractions 0.05 ≤Yp≤0.40 , and zero temperature. The full quantum simulations, in particular, allow us to thoroughly investigate the role and impact of the nuclear symmetry energy on pasta configurations. We use the Sky3D code that solves the Skyrme Hartree-Fock equations on a three-dimensional Cartesian grid. For the nuclear interaction we use the state-of-the-art UNEDF1 parametrization, which was introduced to study largely deformed nuclei, hence is suitable for studies of the nuclear pasta. Density dependence of the nuclear symmetry energy is simulated by tuning two purely isovector observables that are insensitive to the current available experimental data. We find that a minimum total number of nucleons A =2000 is necessary to prevent the results from containing spurious shell effects and to minimize finite size effects. We find that a variety of nuclear pasta geometries are present in the neutron star crust, and the result strongly depends on the nuclear symmetry energy. The impact of the nuclear symmetry energy is less pronounced as the proton fractions increase. Quantum nuclear pasta calculations at T =0 MeV are shown to get easily trapped in metastable states, and possible remedies to avoid metastable solutions are discussed.

  10. Universality of nucleon-nucleon short-range correlations: The factorization property of the nuclear wave function, the relative and center-of-mass momentum distributions, and the nuclear contacts

    NASA Astrophysics Data System (ADS)

    Alvioli, M.; Ciofi degli Atti, C.; Morita, H.

    2016-10-01

    Background: The two-nucleon momentum distributions of nucleons N1 and N2 in a nucleus A , nAN1N2(krel,Kc .m .) , is a relevant quantity that determines the probability of finding two nucleons with relative momentum krel and center-of-mass (c.m.) momentum Kc .m .; at high values of the relative momentum and, at the same time, low values of the c.m. momentum, nAN1N2(krel,Kc .m .) provides information on the short-range structure of nuclei. Purpose: Our purpose is to calculate the momentum distributions of proton-neutron and proton-proton pairs in 3He, 4He, 12C, 16O, and 40Ca, in correspondence to various values of krel and Kc .m .. Methods: The momentum distributions for A >4 nuclei are calculated as a function of the relative, krel, and center-of-mass, Kc.m., momenta and relative angle Θ , within a linked cluster many-body expansion approach, based upon realistic local two-nucleon interaction of the Argonne family and variational wave functions featuring central, tensor, and spin-isospin correlations. Results: Independently of the mass number A , at values of the relative momentum krel≳1.5 -2 fm-1 the momentum distributions exhibit the property of factorization, nAN1N2(krel,Kc .m .) ≃nrelN1N2(krel) nc.m . N1N2(Kc .m .) ; in particular, for p n back-to-back pairs one has nAp n(krel,Kc .m .=0 ) ≃CAp nnD(krel) nc.m . p n(Kc .m .=0 ) , where nD is the deuteron momentum distribution, nc.m . p n(Kc .m .=0 ) the c.m. motion momentum distribution of the pair, and CAp n the p n nuclear contact measuring the number of back-to-back p n pairs with deuteron-like momenta (kp≃-kn,Kc .m .=0 ). Conclusions: The values of the p n nuclear contact are extracted from the general properties of the two-nucleon momentum distributions corresponding to Kc .m .=0 . The Kc .m .-integrated p n momentum distributions exhibit the property nAp n(krel) ≃CAp nnD(krel) but only at very high values of krel, ≳3.5 -4 fm-1. The theoretical ratio of the p p /p n momentum distributions of 4He

  11. Synthesis, structure, and magnetic properties of (6-9)-nuclear Ni(II) trimethylacetates and their heterospin complexes with nitroxides.

    PubMed

    Ovcharenko, Victor; Fursova, Elena; Romanenko, Galina; Eremenko, Igor; Tretyakov, Evgeny; Ikorskii, Vladimir

    2006-07-10

    New polynuclear nickel trimethylacetates [Ni6(OH)4(C5H9O2)8(C5H10O2)4] (6), [Ni7(OH)7(C5H9O2)7(C5H10O2)6(H2O)] x 0.5 C6H14 x 0.5 H2O (7), [Ni8(OH)4(H2O)2(C5H9O2)12] (8), and [Ni9(OH)6(C5H9O2)12(C5H10O2)4] x C5H10O2 x 3 H2O (9), where C5H9O2 is trimethylacetate and C5H10O2 is trimethylacetic acid, have been found. Their structures were determined by X-ray crystallography. Because of their high solubility in low-polarity organic solvents, compounds 6-9 reacted with stable organic radicals to form the first heterospin compounds based on polynuclear Ni(II) trimethylacetate and nitronyl nitroxides containing pyrazole (L(1)-L(3)), methyl (L(4)), or imidazole (L(5)) substituent groups, respectively, in side chain [Ni7(OH)5(C5H9O2)9(C5H10O2)2(L(1))2(H2O)] x 0.5 C6H14 x H2O (6+1a), [Ni7(OH)5(C5H9O2)9(C5H10O2)2(L2)2(H2O)] x H2O (6+1b), [Ni7(OH)5(C5H9O2)9(C5H10O2)2(L(3))2(H2O)] x H2O (6+1c), [Ni6(OH)3(C5H9O2)9(C5H10O2)4(L(4))] x 1.5 C6H14 (6''), and [Ni4OH)3(C5H9O2)5(C5H10O2)4(L(5))] x 1.5 C7H8 (4). Their structures were also determined by X-ray crystallography. Although Ni(II) trimethylacetates may have varying nuclearity and can change their nuclearity during recrystallization or interactions with nitroxides, this family of compounds is easy to study because of its topological relationship. For any of these complexes, the polynuclear framework may be derived from the [Ni6] polynuclear fragment {Ni6(mu4-OH)2(mu3-OH)2(mu2-C5H9O2-O,O')6(mu2-C5H9O2-O,O)(mu4-C5H9O2-O,O,O',O')(C5H10O2)4}, which is shaped like an open book. On the basis of this fragment, the structure of 7-nuclear compounds (7 and 6+1a-c) is conveniently represented as the result of symmetric addition of other mononuclear fragments to the four Ni(II) ions lying at the vertexes of the [Ni6] open book. The 9-nuclear complex is formed by the addition of trinuclear fragments to two Ni(II) ions lying on one of the lateral edges of the [Ni6] open book. This wing of the 9-nuclear complex preserves its structure in

  12. Effect of specimen size and grain orientation on the mechanical and physical properties of NBG-18 nuclear graphite

    NASA Astrophysics Data System (ADS)

    Vasudevamurthy, G.; Byun, T. S.; Pappano, P.; Snead, L. L.; Burchell, T. D.

    2015-07-01

    We present here a comparison of the measured baseline mechanical and physical properties of with grain (WG) and against grain (AG) non-ASTM size NBG-18 graphite. The objectives of the experiments were twofold: (1) assess the variation in properties with grain orientation; (2) establish a correlation between specimen tensile strength and size. The tensile strength of the smallest sized (4 mm diameter) specimens were about 5% higher than the standard specimens (12 mm diameter) but still within one standard deviation of the ASTM specimen size indicating no significant dependence of strength on specimen size. The thermal expansion coefficient and elastic constants did not show significant dependence on specimen size. Experimental data indicated that the variation of thermal expansion coefficient and elastic constants were still within 5% between the different grain orientations, confirming the isotropic nature of NBG-18 graphite in physical properties.

  13. Effect of specimen size and grain orientation on the mechanical and physical properties of NBG-18 nuclear graphite

    SciTech Connect

    Vasudevamurthy, Gokul; Byun, Thak Sang; Pappano, Pete; Snead, Lance L.; Burchell, Tim D.

    2015-03-13

    We present here a comparison of the measured baseline mechanical and physical properties of with grain (WG) and against grain (AG) non-ASTM size NBG-18 graphite. The objectives of the experiments were twofold: (1) assess the variation in properties with grain orientation; (2) establish a correlation between specimen tensile strength and size. The tensile strength of the smallest sized (4 mm diameter) specimens were about 5% higher than the standard specimens (12 mmdiameter) but still within one standard deviation of the ASTM specimen size indicating no significant dependence of strength on specimen size. The thermal expansion coefficient and elastic constants did not show significant dependence on specimen size. Experimental data indicated that the variation of thermal expansion coefficient and elastic constants were still within 5% between the different grain orientations, confirming the isotropic nature of NBG-18 graphite in physical properties.

  14. Effect of specimen size and grain orientation on the mechanical and physical properties of NBG-18 nuclear graphite

    SciTech Connect

    Vasudevamurthy, G.; Byun, T. S.; Pappano, Pete; Snead, Lance L.; Burchell, Tim D.

    2015-03-13

    Here we present a comparison of the measured baseline mechanical and physical properties of with grain (WG) and against grain (AG) non-ASTM size NBG-18 graphite. The objectives of the experiments were twofold: (1) assess the variation in properties with grain orientation; (2) establish a correlation between specimen tensile strength and size. The tensile strength of the smallest sized (4 mm diameter) specimens were about 5% higher than the standard specimens (12 mm diameter) but still within one standard deviation of the ASTM specimen size indicating no significant dependence of strength on specimen size. The thermal expansion coefficient and elastic constants did not show significant dependence on specimen size. Lastly, experimental data indicated that the variation of thermal expansion coefficient and elastic constants were still within 5% between the different grain orientations, confirming the isotropic nature of NBG-18 graphite in physical properties.

  15. Effect of specimen size and grain orientation on the mechanical and physical properties of NBG-18 nuclear graphite

    DOE PAGES

    Vasudevamurthy, G.; Byun, T. S.; Pappano, Pete; ...

    2015-03-13

    Here we present a comparison of the measured baseline mechanical and physical properties of with grain (WG) and against grain (AG) non-ASTM size NBG-18 graphite. The objectives of the experiments were twofold: (1) assess the variation in properties with grain orientation; (2) establish a correlation between specimen tensile strength and size. The tensile strength of the smallest sized (4 mm diameter) specimens were about 5% higher than the standard specimens (12 mm diameter) but still within one standard deviation of the ASTM specimen size indicating no significant dependence of strength on specimen size. The thermal expansion coefficient and elastic constantsmore » did not show significant dependence on specimen size. Lastly, experimental data indicated that the variation of thermal expansion coefficient and elastic constants were still within 5% between the different grain orientations, confirming the isotropic nature of NBG-18 graphite in physical properties.« less

  16. Properties of mixtures of cholesterol with phosphatidylcholine or with phosphatidylserine studied by (13)C magic angle spinning nuclear magnetic resonance.

    PubMed Central

    Epand, Richard M; Bain, Alex D; Sayer, Brian G; Bach, Diana; Wachtel, Ellen

    2002-01-01

    The behavior of cholesterol is different in mixtures with phosphatidylcholine as compared with phosphatidylserine. In (13)C cross polarization/magic angle spinning nuclear magnetic resonance spectra, resonance peaks of the vinylic carbons of cholesterol are a doublet in samples containing 0.3 or 0.5 mol fraction cholesterol with 1-palmitoyl-2-oleoyl phosphatidylserine (POPS) or in cholesterol monohydrate crystals, but a singlet with mixtures of cholesterol and 1-palmitoyl-2-oleoyl phosphatidylcholine (POPC). At these molar fractions of cholesterol with POPS, resonances of the C-18 of cholesterol appear at the same chemical shifts as in pure cholesterol monohydrate crystals. These resonances do not appear in samples of POPS with 0.2 mol fraction cholesterol or with POPC up to 0.5 mol fraction cholesterol. In addition, there is another resonance from the cholesterol C18 that appears in all of the mixtures of phospholipid and cholesterol but not in pure cholesterol monohydrate crystals. Using direct polarization, the fraction of cholesterol present as crystallites in POPS with 0.5 mol fraction cholesterol is found to be 80%, whereas with the same mol fraction of cholesterol and POPC none of the cholesterol is crystalline. After many hours of incubation, cholesterol monohydrate crystals in POPS undergo a change that results in an increase in the intensity of certain resonances of cholesterol monohydrate in (13)C cross polarization/magic angle spinning nuclear magnetic resonance, indicating a rigidification of the C and D rings of cholesterol but not other regions of the molecule. PMID:12324423

  17. Theoretical constraints on the properties of low-mass neutron stars from the equation of state of nuclear matter in the inner crust

    NASA Astrophysics Data System (ADS)

    Wen, Yong-Mei; Wen, De-Hua

    2017-06-01

    By employing four typical equation of states (EOSs) of nuclear matter in the inner crust, the properties of low-mass neutron stars are investigated theoretically. Based on the well-known fact that there is a big gap between the neutron stars and white dwarfs in the mass-radius sequence of compact stars, according to the mass-radius relations of the four adopted EOSs, we conclude that there is a rough forbidden region for the central density and stellar radius to form a compact star; that is, there is no compact star in nature having central density in the region from about 1012kgm-3 to 1017kgm-3 , and there is also no compact star having a radius in the region from about 400 km to 2000 km. Moreover, the properties of the low-mass neutron stars are also explored. It is shown that for a stable neutron star near the minimum mass point, the stellar size (with radius >200 km) is much larger than that of normal neutron stars, and there is a compact "core" concentrated at about 95% of the stellar mass in the inner core with a radius of about 13 km and density higher than the neutron-drip point (4.3 ×1014kgm-3) . This property totally differs from that of normal neutron stars and white dwarfs. Furthermore, the Keplerian period, the moment of inertia, and the surface gravitational redshift of the star near the minimum-mass point are also investigated.

  18. Nuclear Medicine.

    ERIC Educational Resources Information Center

    Badawi, Ramsey D.

    2001-01-01

    Describes the use of nuclear medicine techniques in diagnosis and therapy. Describes instrumentation in diagnostic nuclear medicine and predicts future trends in nuclear medicine imaging technology. (Author/MM)

  19. Nuclear ventriculography

    MedlinePlus

    ... ventriculography (RNV); Multiple gate acquisition scan (MUGA); Nuclear cardiology; Cardiomyopathy - nuclear ventriculography ... 56. Udelson JE, Dilsizian V, Bonow RO. Nuclear cardiology. In: Bonow RO, Mann DL, Zipes DP, Libby ...

  20. Nuclear Medicine.

    ERIC Educational Resources Information Center

    Badawi, Ramsey D.

    2001-01-01

    Describes the use of nuclear medicine techniques in diagnosis and therapy. Describes instrumentation in diagnostic nuclear medicine and predicts future trends in nuclear medicine imaging technology. (Author/MM)

  1. Nuclear data for nuclear transmutation

    SciTech Connect

    Harada, Hideo

    2009-05-04

    Current status on nuclear data for the study of nuclear transmutation of radioactive wastes is reviewed, mainly focusing on neutron capture reactions. It is stressed that the highest-precision frontier research in nuclear data measurements should be a key to satisfy the target accuracies on the nuclear data requested for realizing the nuclear transmutation.

  2. Nuclear data for nuclear transmutation

    NASA Astrophysics Data System (ADS)

    Harada, Hideo

    2009-05-01

    Current status on nuclear data for the study of nuclear transmutation of radioactive wastes is reviewed, mainly focusing on neutron capture reactions. It is stressed that the highest-precision frontier research in nuclear data measurements should be a key to satisfy the target accuracies on the nuclear data requested for realizing the nuclear transmutation.

  3. Physical properties, structure, and shape of radioactive Cs from the Fukushima Daiichi Nuclear Power Plant accident derived from soil, bamboo and shiitake mushroom measurements.

    PubMed

    Niimura, Nobuo; Kikuchi, Kenji; Tuyen, Ninh Duc; Komatsuzaki, Masakazu; Motohashi, Yoshinobu

    2015-01-01

    We conducted an elution experiment with contaminated soils using various aqueous reagent solutions and autoradiography measurements of contaminated bamboo shoots and shiitake mushrooms to determine the physical and chemical characteristics of radioactive Cs from the Fukushima Daiichi Nuclear Power Plant accident. Based on our study results and data in the literature, we conclude that the active Cs emitted by the accident fell to the ground as granular non-ionic materials. Therefore, they were not adsorbed or trapped by minerals in the soil, but instead physically adhere to the rough surfaces of the soil mineral particles. Granular Cs* can be transferred among media, such as soils and plants. The physical properties and dynamic behavior of the granular Cs* is expected to be helpful in considering methods for decontamination of soil, litter, and other media.

  4. Tight Reservoir Properties Derived by Nuclear Magnetic Resonance, Mercury Porosimetry and Computed Microtomography Laboratory Techniques. Case Study of Palaeozoic Clastic Rocks

    NASA Astrophysics Data System (ADS)

    Krakowska, Paulina I.; Puskarczyk, Edyta

    2015-06-01

    Results of the nuclear magnetic resonance (NMR) investigations, mercury porosimetry measurements (MP) and computed microtomography (micro-CT), applied to the tight Palaeozoic rocks from the depths lower than 3000 m, were presented to estimate their reservoir potential. NMR signal analysis and interpretation were performed. Based on NMR driven models, permeability and Free Fluid Index were calculated for data sets divided into homogeneous clusters. Computerized mercury porosimetry results visualization and processing provided useful information, as the automatically determined Swanson parameter is correlated with petrophysical properties of rocks. Micro-CT enriched the image of porous space in qualitative and quantitative ways. Homogeneity of pore space structure was discussed using micro-CT approach. Integration of the results in the frame of reservoir parameters from standard laboratory methods and the modern ones resulted in the improvement of methodology for determining the old, deep-seated, hard sedimentary rocks reservoir potential.

  5. Evaluation of tuff as a medium for a nuclear waste repository: interim status report on the properties of tuff

    SciTech Connect

    Johnstone, J.K.; Wolfsberg, K.

    1980-07-01

    This report is the second in a series of summary briefings to the National Academy of Science`s (NAS) Committee on Radioactive Waste Management dealing with feasibility of disposal of heat-producing radioactive waste in silicic tuff. The interim status of studies of tuff properties determined on samples obtained from Yucca Mountain and Rainier Mesa (G-tunnel) located on the Nevada Test Site (NTS) are discussed. In particular, progress is described on resolving issues identified during the first briefing to the NAS which include behavior of water in tuff when heated, the effect of the presence or absence of water and joints on the thermal/physical properties of tuff and the detailed/complex sorptive properties of highly altered and unaltered tuff. Initial correlations of thermal/physical and sorptive properties with the highly variable porosity and mineralogy are described. Three in-situ, at-depth field experiments, one nearly completed and two just getting underway are described. In particular, the current status of mineralogy and petrology, geochemistry, thermal and mechanical, radiation effects and water behavior studies are described. The goals and initial results of a Mine Design Working Group are discussed. Regional factors such as seismicity, volcanism and hydrology are not discussed.

  6. Coordination compounds in nuclear medicine

    SciTech Connect

    Jurisson, S.; Berning, D.; Wei Jia; Dangshe Ma )

    1993-05-01

    Radiopharmaceuticals, drugs containing a radionuclide, are used routinely in nuclear medicine departments for the diagnosis of disease and are under investigation for use in the treatment of disease. Nuclear medicine takes advantage of both the nuclear properties of the radionuclide and the pharmacological properties of the radiopharmaceutical. Herein lies the real strength of nuclear medicine, the ability to monitor biochemical and physiological functions in vivo. This review discusses the coordination chemistry that forms the basis for nuclear medicine applications of the FDA-approved radiopharmaceuticals that are in clinical use, and of the most promising diagnostic and therapeutic radiopharmaceuticals that are in various stages of development. 232 refs.

  7. Nuclear effects in Neutrino Nuclear Cross-sections

    SciTech Connect

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

    2008-02-21

    Nuclear effects in the quasielastic and inelastic scattering of neutrinos(antineutrinos) from nuclear targets have been studied. The calculations are done in the local density approximation which take into account the effect of nucleon motion as well as renormalisation of weak transition strengths in the nuclear medium. The inelastic reaction leading to production of pions is calculated in a {delta} dominance model taking into account the renormalization of {delta} properties in the nuclear medium.

  8. Synthesis, crystal structure and properties of a novel tetra-nuclear Cu complex of ANPyO

    SciTech Connect

    Liu Jinjian; Liu Zuliang; Cheng Jian

    2013-01-15

    A transition metal Cu complex with 2,6-diamino-3,5-dinitropyridine-N-oxide (ANPyO) ligand has been synthesized and its crystal structure has been analyzed by X-ray diffraction methods. The crystal belongs to Triclinic system with space group P-1. The cell parameters are a=8.6710(17) nm, b=11.226(2) nm, c=18.741(4) nm, {alpha}=98.26(3), {beta}=102.60(3), {gamma}=109.17(3), V=1635.1(6) nm{sup 3}, D{sub c}=1.957 g/cm{sup 3}, {mu}=2.663 mm{sup -1}, F(000)=968, Z=2, R{sub 1}=0.0764, WR{sub 2}=0.1608. The thermal decomposition process of the title complex was studied by means of the TG-DTG and DSC at a heating rate of 20 K/min. It consists of two slow endothermic peaks and one violent exothermic peak with 37.22% residues. The apparent activation energy and pre-exponential factor of the complex in thermal decomposition process were calculated by means of the Kissinger method and Ozawa-Doyle method. The thermal decomposition of AP was accelerated due to the catalyst of the complex, it suggests that the complex can provide theoretical support to further performance study as it is added to the propellant formulations to regulate the burning rate. - Graphical abstract: A novel tetra-nuclear Cu complex of ANPyO was synthesized and its molecular structure was measured. Highlights: Black-Right-Pointing-Pointer We have synthesized and characterized a new tetra-nuclear Cu complex. Black-Right-Pointing-Pointer We have measured its molecular structure and thermal decomposition. Black-Right-Pointing-Pointer A special coordination mode between ligand and central copper atoms has been obtained. Black-Right-Pointing-Pointer It provides theoretical support to further performance study as energetic catalyst.

  9. The Prediction of Middle Distillate Fuel Properties Using Liquid Chromatography-Proton Nuclear Magnetic Resonance Spectroscopy Data

    DTIC Science & Technology

    1989-06-01

    It is mandatory that all factors influencing operability be understood because it is essential that DOD’s mission not be unduly influenced by short...affecting other properties such as gravity, viscosity, etc., which are essential for diesel engine performance. Generally at or above 20F, the wax...emissions from the fuel tank, especially if recent engine operation has heated the fuel by recirculation. It is essential that blending be done

  10. Synthesis, crystal structures, photoluminescent, magnetic and chiroptical properties of two homochiral ErIII complexes with different nuclearity

    NASA Astrophysics Data System (ADS)

    Li, Xi-Li; Liu, Ying-Fan; Zhang, Xue-Li; Cheng, Conghui; Zheng, Xianjun; Zhu, Cancan; Zhou, Liming

    2017-06-01

    Employing chiral bis-bidentate N-donor ligand, (+)-2,5-bis(4,5-pinene-2-pyridyl) pyrazine (L), as a bridging ligand for Er(dbm)3H2O, and depending on the ratio control of reactants, two mono- and dinuclear homochiral ErIII complexes with the formulae Er(dbm)3L·2H2O (1) (dbm- = dibenzoylmethanate) and Er2(dbm)6L·6H2O (2) have been synthesized and structurally characterized. Circular dichroic (CD) spectra verify their chiroptical activities. Investigations on the luminescent properties of complexes 1 and 2 demonstrate that they exhibit characteristic near-infrared (NIR) luminescence of the ErIII ion at around 1533 nm and the emission intensity of the mononuclear complex 1 is much larger than that of dinuclear species 2, the reason of which is elucidated in this work. In addition, the measurements of magnetic properties indicate that the direct-current (dc) magnetic behaviors of complexes 1 and 2 mainly result from the thermal depopulation of the excited MJ sublevels of the ErIII ions. Notablely, complex 2 is the first example of chiral polynuclear lanthanide complexes with NIR-luminescence property.

  11. Corrosion property of 9Cr-ODS steel in nitric acid solution for spent nuclear fuel reprocessing

    SciTech Connect

    Takeuchi, M.; Koizumi, T.; Inoue, M.; Koyama, S.I.

    2013-07-01

    Corrosion tests of oxide dispersion strengthened with 9% Cr (9Cr-ODS) steel, which is one of the desirable materials for cladding tube of sodium-cooled fast reactors, in pure nitric acid solution, spent FBR fuel solution, and its simulated solution were performed to understand the corrosion behavior in a spent nuclear fuel reprocessing. In this study, the 9Cr-ODS steel with lower effective chromium content was evaluated to understand the corrosion behavior conservatively. As results, the tube-type specimens of the 9Cr-ODS steels suffered severe weight loss owing to active dissolution at the beginning of the immersion test in pure nitric acid solution in the range from 1 to 3.5 M. In contrast, the weight loss was decreased and they showed a stable corrosion in the higher nitric acid concentration, the dissolved FBR fuel solution, and its simulated solution by passivation. The corrosion rates of the 9Cr-ODS steel in the dissolved FBR fuel solution and its simulated solution were 1-2 mm/y and showed good agreement with each other. The passivation was caused by the shift of corrosion potential to noble side owing to increase in nitric acid concentration or oxidative ions in the dissolved FBR fuel solution and the simulated spent fuel solution. (authors)

  12. A Fungal Effector With Host Nuclear Localization and DNA-Binding Properties Is Required for Maize Anthracnose Development.

    PubMed

    Vargas, Walter A; Sanz-Martín, José M; Rech, Gabriel E; Armijos-Jaramillo, Vinicio D; Rivera, Lina P; Echeverria, María Mercedes; Díaz-Mínguez, José M; Thon, Michael R; Sukno, Serenella A

    2016-02-01

    Plant pathogens have the capacity to manipulate the host immune system through the secretion of effectors. We identified 27 putative effector proteins encoded in the genome of the maize anthracnose pathogen Colletotrichum graminicola that are likely to target the host's nucleus, as they simultaneously contain sequence signatures for secretion and nuclear localization. We functionally characterized one protein, identified as CgEP1. This protein is synthesized during the early stages of disease development and is necessary for anthracnose development in maize leaves, stems, and roots. Genetic, molecular, and biochemical studies confirmed that this effector targets the host's nucleus and defines a novel class of double-stranded DNA-binding protein. We show that CgEP1 arose from a gene duplication in an ancestor of a lineage of monocot-infecting Colletotrichum spp. and has undergone an intense evolution process, with evidence for episodes of positive selection. We detected CgEP1 homologs in several species of a grass-infecting lineage of Colletotrichum spp., suggesting that its function may be conserved across a large number of anthracnose pathogens. Our results demonstrate that effectors targeted to the host nucleus may be key elements for disease development and aid in the understanding of the genetic basis of anthracnose development in maize plants.

  13. Structural and dynamic properties of amorphous solid dispersions: the role of solid-state nuclear magnetic resonance spectroscopy and relaxometry.

    PubMed

    Paudel, Amrit; Geppi, Marco; Van den Mooter, Guy

    2014-09-01

    Amorphous solid dispersions (ASDs) are one of the frontier strategies to improve solubility and dissolution rate of poorly soluble drugs and hence tackling the growing challenges in oral bioavailability. Pharmaceutical performance, physicochemical stability, and downstream processability of ASD largely rely on the physical structure of the product. This necessitates in-depth characterization of ASD microstructure. Solid-state nuclear magnetic resonance (SS-NMR) techniques bear the ultimate analytical capabilities to provide the molecular level information on the dynamics and phase compositions of amorphous dispersions. SS-NMR spectroscopy/relaxometry, as a single and nondestructive technique, can reveal diverse and critical structural information of complex ASD formulations that are barely amenable from any other existing technique. The purpose of the current article is to review the recent most important studies on various sophisticated and information-rich one-dimensional and two-dimensional SS-NMR spectroscopy/relaxometry for the analysis of molecular mobility, miscibility, drug-carrier interactions, crystallinity, and crystallization in ASD. Some specific examples on microstructural elucidations of challenging ASD using multidimensional and multinuclear SS-NMR are presented. Additionally, some relevant examples on the utility of solution-NMR and NMR-imaging techniques for the investigation of the dissolution behavior of ASD are gathered.

  14. Anomalous Solute Transport in Saturated Porous Media: Linking Transport Model Parameters to Electrical and Nuclear Magnetic Resonance Properties

    NASA Astrophysics Data System (ADS)

    Swanson, R. D.; Binley, A. M.; Keating, K.; France, S.; Osterman, G. K.; Day-Lewis, F. D.; Singha, K.

    2013-12-01

    The advection-dispersion equation fails to describe non-Fickian solute transport in saturated porous media, necessitating the use of other models. The dual-domain mass transfer (DDMT) model partitions the total porosity into mobile and less-mobile domains with solute exchange between the domains; consequently, the DDMT model can produce a better fit to breakthrough curves (BTCs) in systems defined by more- and less-mobile components. However, direct experimental estimation of DDMT model parameters such as rate of exchange and the mobile and less-mobile porosities remains elusive. Consequently, model parameters are often calculated purely as a model fitting exercise. There is a clear need for material characterization techniques that can offer some insight into the pore space geometrical arrangement, particularly if such techniques can be extended to the field scale. Here, we interpret static direct-current (DC) resistivity, complex resistivity (CR) and nuclear magnetic resonance (NMR) geophysical measurements in the characterization of mass transfer parameters. We use two different samples of the zeolite clinoptilolite, a material shown to demonstrate solute mass transfer due to a significant intragranular porosity, along with glass beads as a control. We explore the relation between geophysical and DDMT parameters in conjunction with supporting material characterization methods. Our results reveal how these geophysical measurements can offer some insight into the pore structures controlling the observed anomalous transport behavior.

  15. Evaluated nuclear structure data file

    NASA Astrophysics Data System (ADS)

    Tuli, J. K.

    The Evaluated Nuclear Structure Data File (ENSDF) contains the evaluated nuclear properties of all known nuclides. These properties are derived both from nuclear reaction and radioactive decay measurements. All experimental data are evaluated to create the adopted properties for each nuclide. ENSDF, together with other numeric and biographic files, can be accessed on-line through the INTERNET or modem. Some of the databases are also available on the World Wide Web. The structure and the scope of ENSDF are presented along with the on-line access system of the National Nuclear Data Center at Brookhaven National Laboratory.

  16. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.

    Several court cases involving acquisition, use, and disposal of property by institutions of higher education are briefly summarized in this chapter. Cases discussed touch on such topics as municipal annexation of university property; repurchase of properties temporarily allocated to faculty members; implications of zoning laws and zoning board…

  17. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.

    Several court cases involving acquisition, use, and disposal of property by institutions of higher education are briefly summarized in this chapter. Cases discussed touch on such topics as municipal annexation of university property; repurchase of properties temporarily allocated to faculty members; implications of zoning laws and zoning board…

  18. Structural features and ligand binding properties of tandem WW domains from YAP and TAZ, nuclear effectors of the Hippo pathway.

    PubMed

    Webb, Claire; Upadhyay, Abhishek; Giuntini, Francesca; Eggleston, Ian; Furutani-Seiki, Makoto; Ishima, Rieko; Bagby, Stefan

    2011-04-26

    The paralogous multifunctional adaptor proteins YAP and TAZ are the nuclear effectors of the Hippo pathway, a central mechanism of organ size control and stem cell self-renewal. WW domains, mediators of protein-protein interactions, are essential for YAP and TAZ function, enabling interactions with PPxY motifs of numerous partner proteins. YAP has single and double WW domain isoforms (YAP1 and YAP2) whereas only a single WW domain isoform of TAZ has been described to date. Here we identify the first example of a double WW domain isoform of TAZ. Using NMR, we have characterized conformational features and peptide binding of YAP and TAZ tandem WW domains (WW1-WW2). The solution structure of YAP WW2 confirms that it has a canonical three-stranded antiparallel β-sheet WW domain fold. While chemical shift-based analysis indicates that the WW domains in the tandem WW pairs retain the characteristic WW domain fold, 15N relaxation data show that, within the respective WW pairs, YAP WW1 and both WW1 and WW2 of TAZ undergo conformational exchange. 15N relaxation data also indicate that the linker between the WW domains is flexible in both YAP and TAZ. Within both YAP and TAZ tandem WW pairs, WW1 and WW2 bind single PPxY-containing peptide ligand concurrently and noncooperatively with sub-mM affinity. YAP and TAZ WW1-WW2 bind a dual PPxY-containing peptide with approximately 6-fold higher affinity. Our results indicate that both WW domains in YAP and TAZ are functional and capable of enhanced affinity binding to multi-PPxY partner proteins such as LATS1, ErbB4, and AMOT.

  19. Cytotoxic Properties and Complete Nuclear Magnetic Resonance Assignment of Isolated Xanthones from the Root of Garcinia cowa Roxb.

    PubMed Central

    Wahyuni, Fatma Sri; Shaari, Khozirah; Stanslas, Johnson; Lajis, Nordin HJ; Hamidi, Dachriyanus

    2016-01-01

    Objective: To isolate compounds from the roots of Garcinia cowa and to evaluated their cytotoxic activity against breast (MCF-7), prostate (DU-145), and lung (H-460) cell lines. Materials and Methods: The ground air-dried root was sequentially macerated with hexane, dichloromethane (DCM), ethyl acetate (EtOAc), and methanol. The DCM soluble extract was fractionated by vacuum liquid chromatography, column chromatography, and radial chromatography over silica gel with hexane, EtOAc and methanol as eluent in progressively increasing polarity manner; to yield three compounds. Their structures were elucidated based on their spectroscopic data and their comparison with those of the literature. The cytotoxicity of isolated compounds was carried out against human cell lines by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide colorimetric assay. The extract was added at various concentrations (0.1, 1, 10 and 100 mg/ml). The level of cytotoxicity was determined by calculating the level of IC50 that was based on the percentage of the cell death following the 24 h incubation with the extract. Results: Phytochemical study on the roots of G. cowa yielded rubraxanthone (3), cowanine (4) and 1,5-dihydroxyxanthone (5). Compound 4 with an IC50 value of 4.1 ± 1.0 μM, 5.4 ± 2.3 μM and 11.3 ± 10.0 μM against MCF-7, H-460, and DU-145, respectively while compound 3 was found to be in active. Conclusion: The results indicate that G. cowa roots could be important sources of natural cytotoxic compounds. SUMMARY Isolation of cytotoxic compounds from Garcinia cowaCowanine is the active constituent from the roots of Garcinia cowaComplete nuclear magnetic resonance assignment of isolated compoundsMS fragmentation of rubraxanthone. PMID:27041859

  20. Dynamic nuclear polarization properties of nitroxyl radical in high viscous liquid using Overhauser-enhanced Magnetic Resonance Imaging (OMRI)

    NASA Astrophysics Data System (ADS)

    Kumara Dhas, M.; Utsumi, Hideo; Jawahar, A.; Milton Franklin Benial, A.

    2015-08-01

    The dynamic nuclear polarization (DNP) studies were carried out for 15N labeled carbamoyl-PROXYL in pure water and pure water/glycerol mixtures of different viscosities (1.8 cP, 7 cP and 14 cP). The dependence of DNP parameters was demonstrated over a range of agent concentration, viscosities, RF power levels and ESR irradiation time. DNP spectra were also recorded for 2 mM concentration of 15N labeled carbamoyl-PROXYL in pure water and pure water/glycerol mixtures of different viscosities. The DNP factors were measured as a function of ESR irradiation time, which increases linearly up to 2 mM agent concentration in pure water and pure water/glycerol mixtures of different viscosities. The DNP factor started declining in the higher concentration region (∼3 mM), which is due to the ESR line width broadening. The water proton spin-lattice relaxation time was measured at very low Zeeman field (14.529 mT). The increased DNP factor (35%) was observed for solvent 2 (η = 1.8 cP) compared with solvent 1 (η = 1 cP). The increase in the DNP factor was brought about by the shortening of water proton spin-lattice relaxation time of solvent 2. The decreased DNP factors (30% and 53%) were observed for solvent 3 (η = 7 cP) and solvent 4 (η = 14 cP) compared with solvent 2, which is mainly due to the low value of coupling parameter in high viscous liquid samples. The longitudinal relaxivity, leakage factor and coupling parameter were estimated. The coupling parameter values reveal that the dipolar interaction as the major mechanism. The longitudinal relaxivity increases with the increasing viscosity of pure water/glycerol mixtures. The leakage factor showed an asymptotic increase with the increasing agent concentration. It is envisaged that the results reported here may provide guidelines for the design of new viscosity prone nitroxyl radicals, suited to the biological applications of DNP.

  1. Dynamic nuclear polarization properties of nitroxyl radical in high viscous liquid using Overhauser-enhanced Magnetic Resonance Imaging (OMRI).

    PubMed

    Kumara Dhas, M; Utsumi, Hideo; Jawahar, A; Milton Franklin Benial, A

    2015-08-01

    The dynamic nuclear polarization (DNP) studies were carried out for (15)N labeled carbamoyl-PROXYL in pure water and pure water/glycerol mixtures of different viscosities (1.8cP, 7cP and 14cP). The dependence of DNP parameters was demonstrated over a range of agent concentration, viscosities, RF power levels and ESR irradiation time. DNP spectra were also recorded for 2mM concentration of (15)N labeled carbamoyl-PROXYL in pure water and pure water/glycerol mixtures of different viscosities. The DNP factors were measured as a function of ESR irradiation time, which increases linearly up to 2mM agent concentration in pure water and pure water/glycerol mixtures of different viscosities. The DNP factor started declining in the higher concentration region (∼3mM), which is due to the ESR line width broadening. The water proton spin-lattice relaxation time was measured at very low Zeeman field (14.529mT). The increased DNP factor (35%) was observed for solvent 2 (η=1.8cP) compared with solvent 1 (η=1cP). The increase in the DNP factor was brought about by the shortening of water proton spin-lattice relaxation time of solvent 2. The decreased DNP factors (30% and 53%) were observed for solvent 3 (η=7cP) and solvent 4 (η=14cP) compared with solvent 2, which is mainly due to the low value of coupling parameter in high viscous liquid samples. The longitudinal relaxivity, leakage factor and coupling parameter were estimated. The coupling parameter values reveal that the dipolar interaction as the major mechanism. The longitudinal relaxivity increases with the increasing viscosity of pure water/glycerol mixtures. The leakage factor showed an asymptotic increase with the increasing agent concentration. It is envisaged that the results reported here may provide guidelines for the design of new viscosity prone nitroxyl radicals, suited to the biological applications of DNP. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Signalling properties of identified deep cerebellar nuclear neurons related to eye and head movements in the alert cat.

    PubMed Central

    Gruart, A; Delgado-García, J M

    1994-01-01

    1. The spike activity of deep cerebellar nuclear neurons was recorded in the alert cat during spontaneous and during vestibularly and visually induced eye movements. 2. Neurons were classified according to their location in the nuclei, their antidromic activation from projection sites, their sensitivity to eye position and velocity during spontaneous eye movements, and their responses to vestibular and optokinetic stimuli. 3. Type I EPV (eye position and velocity) neurons were located mainly in the posterior part of the fastigial nucleus and activated antidromically almost exclusively from the medial longitudinal fasciculus close to the oculomotor complex. These neurons, reported here for the first time, increased their firing rate during saccades and eye fixations towards the contralateral hemifield. Their position sensitivity to eye fixations in the horizontal plane was 5.3 +/- 2.6 spikes s-1 deg-1 (mean +/- S.D.). Eye velocity sensitivity during horizontal saccades was 0.71 +/- 0.52 spikes s-1 deg-1 s-1. Variability of their firing rate during a given eye fixation was higher than that shown by abducens motoneurons. 4. Type I EPV neurons increased their firing rate during ipsilateral head rotations at 0.5 Hz with a mean phase lead over eye position of 95.3 +/- 9.5 deg. They were also activated by contralateral optokinetic stimulation at 30 deg s-1. Their sensitivity to eye position and velocity in the horizontal plane during vestibular and optokinetic stimuli yielded values similar to those obtained for spontaneous eye movements. 5. Type II neurons were located in both fastigial and dentate nuclei and were activated antidromically from the restiform body, the medial longitudinal fasciculus close to the oculomotor complex, the red nucleus and the pontine nuclei. Type II neurons were not related to spontaneous eye movements. These neurons increased their firing rate in response to contralateral head rotation and during ipsilateral optokinetic stimulation, and

  3. Nuclear magnetic resonance and optosensing properties of di-2-thienyl ketone p-nitrophenylhydrazone (DSKNPH) in non-aqueous media.

    PubMed

    Bakir, Mohammed; Green, Orville; Gyles, Colin; Mangaro, Basil; Porter, Roy

    2004-03-10

    The compound di-2-thienyl ketone p-nitrophenylhydrazone (DSKNPH) melting point 168-170 degrees C was isolated in good yield from the reaction between di-2-thienyl ketone (DSK) and p-nitrophenylhydrazine in refluxing ethanol containing a few drop of concentrated HCl. Nuclear magnetic resonance studies on DSKNPH in non-aqueous solvents revealed strong solvent and temperature dependence due to solvent-solute interactions. Optical measurements on DSKNPH in DMSO in the presence and absence of KPF(6) gave extinction coefficients of 83,300+/-2000 and 25,600+/-2000M(-1)cm(-1) at 612 and 427nm at 295K. In CH(2)Cl(2), extinction coefficient of 34,000+/-2000M(-1)cm(-1) was calculated at 422nm. When DMSO solutions of DSKNPH were allowed to interact with DMSO solutions of NaBH(4) the low energy electronic state becomes favorable and when DMSO solutions of DSPKNPH where allowed to interact with DMSO solutions of KPF(6) or NaBF(4), the high energy electronic state becomes favorable. The reversible BH(4)(-)/BF(4)(-) interconversion points to physical interactions between these species and DSKNPH and hints to the possible use of DSKNPH as a spectrophotometric sensor for a variety of physical and chemical stimuli. Thermo-optical measurements on DSKNPH in DMSO confirmed the reversible interconversion between the high and low energy electronic states of DSKNPH and allowed for the calculations of the thermodynamic activation parameters of DSKNPH. Changes in enthalpy (DeltaH(slashed circle)) of +57.67+/-4.20; 27.15+/-0.90kJmol(-1), entropy (DeltaS(slashed circle)) of +160+/-12.88; 83+/-2.91Jmol(-1) and free energy (DeltaG(slashed circle)) of -8.52+/-0.40; 2.66+/-0.25kJmol(-1) were calculated at 295K in the absence and presence of NaBH(4), respectively. Manipulation of the equilibrium distribution of the high and low energy electronic states of DSKNPH allowed for the use of these systems (DSKNPH and surrounding solvent molecules) as molecular sensors for group I and II metal ions. Group

  4. Method and apparatus for studying high-temperature properties of conductive materials in the interests of nuclear power engineering

    SciTech Connect

    Savvatimskiy, A. I. Onufriev, S. V.

    2016-12-15

    Physical processes during a rapid (microsecond) heating of metals, carbon, and their compounds by a single pulse of electric current are discussed. Effects arising in such short-term heating near the melting point are noted: the electron emission and heat capacity anomalies and the possible occurrence of Frenkel pair (interstitial atom and vacancy). The problem of measuring the temperature using optical methods under pulse heating is considered, including the use of a specimen in the form of a blackbody model. The melting temperature of carbon (4800–4900 K) is measured at increased pulse pressure. The results of studying the properties of metals (by example of zirconium and hafnium) and of zirconium carbide at high temperatures are discussed. The schematics of the pulse setups and the instrumentation, as well as specimens for a pulse experiment, are presented.

  5. Formation and physical properties of uranium hydride under conditions relevant to metallic fuel and nuclear waste storage

    NASA Astrophysics Data System (ADS)

    Orr, Robin; Godfrey, Hugh; Broan, Chris; Goddard, Dave; Woodhouse, Guy; Durham, Peter; Diggle, Andrew; Bradshaw, John

    2016-08-01

    The formation of uranium hydride is recognised as a hazard during the storage of uranium metal owing to its potentially pyrophoric properties. This study has assessed the influence of water vapour on the potential for uranium hydride to form at low temperatures and shows that it increases the duration of the induction period but does not necessarily prevent uranium hydride formation and also does not significantly change the reaction rate with hydrogen. It is further shown that the α-UH3 fraction in the uranium hydride gradually increases at decreasing temperatures and is likely to be the dominant phase formed under typical storage conditions. Particle morphology and specific surface area of uranium hydride prepared between 30 °C and 200 °C have also been characterised but show only modest variation compared with the phase composition.

  6. Method and apparatus for studying high-temperature properties of conductive materials in the interests of nuclear power engineering

    NASA Astrophysics Data System (ADS)

    Savvatimskiy, A. I.; Onufriev, S. V.

    2016-12-01

    Physical processes during a rapid (microsecond) heating of metals, carbon, and their compounds by a single pulse of electric current are discussed. Effects arising in such short-term heating near the melting point are noted: the electron emission and heat capacity anomalies and the possible occurrence of Frenkel pair (interstitial atom and vacancy). The problem of measuring the temperature using optical methods under pulse heating is considered, including the use of a specimen in the form of a blackbody model. The melting temperature of carbon (4800-4900 K) is measured at increased pulse pressure. The results of studying the properties of metals (by example of zirconium and hafnium) and of zirconium carbide at high temperatures are discussed. The schematics of the pulse setups and the instrumentation, as well as specimens for a pulse experiment, are presented.

  7. The nuclear properties and extended morphologies of powerful radio galaxies: the roles of host galaxy and environment

    NASA Astrophysics Data System (ADS)

    Miraghaei, H.; Best, P. N.

    2017-04-01

    Powerful radio Galaxies exist as either compact or extended sources, with the extended sources traditionally classified by their radio morphologies as Fanaroff-Riley (FR) type I and II sources. FRI/FRII and compact radio galaxies have also been classified by their optical spectra into two different types: high excitation (HERG; quasar-mode) and low excitation (LERG; jet-mode). We present a catalogue of visual morphologies for a complete sample of >1000 1.4-GHz-selected extended radio sources from the Sloan Digital Sky Survey. We study the environment and host galaxy properties of FRI/FRII and compact sources, classified into HERG/LERG types, in order to separate and distinguish the factors that drive the radio morphological variations from those responsible for the spectral properties. Comparing FRI LERGs with FRII LERGs at fixed stellar mass and radio luminosity, we show that FRIs typically reside in richer environments and are hosted by smaller galaxies with higher mass surface density; this is consistent with extrinsic effects of jet disruption driving the Fanaroff-Riley (FR) dichotomy. Using matched samples of HERGs and LERGs, we show that HERG host galaxies are more frequently star forming, with more evidence for disc-like structure than LERGs, in accordance with currently favoured models of fundamentally different fuelling mechanisms. Comparing FRI/FRII LERGs with compact LERGs, we find the primary difference is that compact objects typically harbour less massive black holes. This suggests that lower mass black holes may be less efficient at launching stable radio jets, or do so for shorter times. Finally, we investigate rarer sub-classes: wide-angle-tailed, head-tail, FR-hybrid and double-double sources.

  8. The nuclear properties and extended morphologies of powerful radio galaxies: the roles of host galaxy and environment

    NASA Astrophysics Data System (ADS)

    Miraghaei, H.; Best, P. N.

    2017-01-01

    Powerful radio galaxies exist as either compact or extended sources, with the extended sources traditionally classified by their radio morphologies as Fanaroff-Riley (FR) type I and II sources. FRI/II and compact radio galaxies have also been classified by their optical spectra into two different types: high excitation (HERG; quasar-mode) and low excitation (LERG; jet-mode). We present a catalogue of visual morphologies for a complete sample of >1000 1.4-GHz-selected extended radio sources from the Sloan Digital Sky Survey. We study the environment and host galaxy properties of FRI/II and compact sources, classified into HERG/LERG types, in order to separate and distinguish the factors that drive the radio morphological variations from those responsible for the spectral properties. Comparing FRI LERGs with FRII LERGs at fixed stellar mass and radio luminosity, we show that FRIs typically reside in richer environments and are hosted by smaller galaxies with higher mass surface density; this is consistent with extrinsic effects of jet disruption driving the FR dichotomy. Using matched samples of HERGs and LERGs, we show that HERG host galaxies are more frequently star-forming, with more evidence for disk-like structure than LERGs, in accordance with currently-favoured models of fundamentally different fuelling mechanisms. Comparing FRI/II LERGs with compact LERGs, we find the primary difference is that compact objects typically harbour less massive black holes. This suggests that lower-mass black holes may be less efficient at launching stable radio jets, or do so for shorter times. Finally, we investigate rarer sub-classes: wide-angle tail, head-tail, FR-hybrid and double-double sources.

  9. A Tat-grafted anti-nucleic acid antibody acquires nuclear-localization property and a preference for TAR RNA

    SciTech Connect

    Jeong, Jong-Geun; Kim, Dong-Sik; Kim, Yong-Sung; Kwon, Myung-Hee

    2011-03-18

    Highlights: {yields} We generate '{sub H3}Tat-3D8' by grafting Tat{sub 48-60} peptide to VH CDR of 3D8 scFv antibody. {yields} {sub H3}Tat-3D8 antibody retains nucleic acid binding and hydrolyzing activities. {yields} {sub H3}Tat-3D8 acquires a preference for TAR RNA structure. {yields} Properties of Tat{sub 48-60} is transferred to an antibody via Tat-grafting into a CDR. -- Abstract: The 3D8 single chain variable fragment (3D8 scFv) is an anti-nucleic acid antibody that can hydrolyze nucleic acids and enter the cytosol of cells without reaching the nucleus. The Tat peptide, derived from the basic region of the HIV-1 Tat protein, translocates to cell nuclei and has TAR RNA binding activity. In this study, we generated a Tat-grafted antibody ({sub H3}Tat-3D8) by replacing complementarity-determining region 3 (CDR3) within the VH domain of the 3D8 scFv with a Tat{sub 48-60} peptide (GRKKRRQRRRPPQ). {sub H3}Tat-3D8 retained the DNA-binding and DNA-hydrolyzing activity of the scFv, and translocated to the nuclei of HeLa cells and preferentially recognized TAR RNA. Thus, the properties associated with the Tat peptide were transferred to the antibody via Tat-grafting without loss of the intrinsic DNA-binding and hydrolyzing activities of the 3D8 scFv antibody.

  10. Nuclear "waffles"

    NASA Astrophysics Data System (ADS)

    Schneider, A. S.; Berry, D. K.; Briggs, C. M.; Caplan, M. E.; Horowitz, C. J.

    2014-11-01

    Background: The dense neutron-rich matter found in supernovae and inside neutron stars is expected to form complex nonuniform phases, often referred to as nuclear pasta. The pasta shapes depend on density, temperature and proton fraction and determine many transport properties in supernovae and neutron star crusts. Purpose: To characterize the topology and compute two observables, the radial distribution function (RDF) g (r ) and the structure factor S (q ) , for systems with proton fractions Yp=0.10 ,0.20 ,0.30 , and 0.40 at about one-third of nuclear saturation density, n =0.050 fm-3 , and temperatures near k T =1 MeV . Methods: We use two recently developed hybrid CPU/GPU codes to perform large scale molecular dynamics (MD) simulations with 51 200 and 409 600 nucleons. From the output of the MD simulations we obtain the two desired observables. Results: We compute and discuss the differences in topology and observables for each simulation. We observe that the two lowest proton fraction systems simulated, Yp=0.10 and 0.20 , equilibrate quickly and form liquidlike structures. Meanwhile, the two higher proton fraction systems, Yp=0.30 and 0.40 , take a longer time to equilibrate and organize themselves in solidlike periodic structures. Furthermore, the Yp=0.40 system is made up of slabs, lasagna phase, interconnected by defects while the Yp=0.30 systems consist of a stack of perforated plates, the nuclear waffle phase. Conclusions: The periodic configurations observed in our MD simulations for proton fractions Yp≥0.30 have important consequences for the structure factors S (q ) of protons and neutrons, which relate to many transport properties of supernovae and neutron star crust. A detailed study of the waffle phase and how its structure depends on temperature, size of the simulation, and the screening length showed that finite-size effects appear to be under control and, also, that the plates in the waffle phase merge at temperatures slightly above 1.0 MeV and

  11. Nuclear Mechanics in Disease

    PubMed Central

    Zwerger, Monika; Ho, Chin Yee; Lammerding, Jan

    2015-01-01

    Over the past two decades, the biomechanical properties of cells have emerged as key players in a broad range of cellular functions, including migration, proliferation, and differentiation. Although much of the attention has focused on the cytoskeletal networks and the cell’s microenvironment, relatively little is known about the contribution of the cell nucleus. Here, we present an overview of the structural elements that determine the physical properties of the nucleus and discuss how changes in the expression of nuclear components or mutations in nuclear proteins can affect not only nuclear mechanics but also modulate cytoskeletal organization and diverse cellular functions. These findings illustrate that the nucleus is tightly integrated into the surrounding cellular structure. Consequently, changes in nuclear structure and composition are highly relevant to normal development and physiology and can contribute to many human diseases, such as muscular dystrophy, dilated cardiomyopathy, (premature) aging, and cancer. PMID:21756143

  12. Nuclear Structure Near the Drip Lines

    SciTech Connect

    Nazarewicz, W.

    1998-08-10

    Experiments with beams of unstable nuclei will make it possible to look closely into many aspects of the nuclear many-body problem. Theoretically, exotic nuclei represent a formidable challenge for the nuclear many-body theories and their power to predict nuclear properties in nuclear terra incognita.

  13. Nuclear physics: Macroscopic aspects

    SciTech Connect

    Swiatecki, W.J.

    1993-12-01

    A systematic macroscopic, leptodermous approach to nuclear statics and dynamics is described, based formally on the assumptions {h_bar} {yields} 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.

  14. Ultraviolet radiation-induced modifications of the optical and registration properties of a CR-39 nuclear track detector

    NASA Astrophysics Data System (ADS)

    Saad, A. F.; Al-Faitory, N. M.; Hussein, M.; Mohamed, R. A.

    2015-09-01

    The UV-VIS (ultraviolet-visible) spectra and etching characteristics of poly allyl diglycol carbonate (PADC, a form of the CR-39 polymer) detector films after exposure to UV radiation for various times have been studied. Etching experiments were carried out on the UV-exposed CR-39 detectors after alpha particle and fission-fragment irradiation using a 252Cf source. The bulk and track etch rates were measured using the alpha and fission-fragment track diameters, and the sensitivity and the detection efficiency were also determined. The optical band gap for both indirect and direct transitions was calculated based on the absorption edge of the UV spectra of the pristine and variously UV-exposed detectors. The optical band gap evidently indicates a gradual change in the optical properties of the CR-39 detector that is induced by the UV radiation. This study shows that the UV-exposed CR-39 detectors were demonstrated to be highly sensitive to alpha particles, but proved to be somewhat less sensitive to the fission fragments.

  15. Property.

    ERIC Educational Resources Information Center

    Goldblatt, Steven M.; Piele, Philip K.

    This chapter reviews 1982 cases related to school property. Cases involving citizen efforts to overturn school board decisions to close schools dominate the property chapter, and courts continue to uphold school board authority to close schools, transfer students, and sell or lease the buildings. Ten cases involving detachment and attachment of…

  16. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.; Johnson, Margaret M.

    This chapter deals with 1981 cases involving disputes over property. Cases involving the detachment and attachment of land continue to dominate the property chapter with 11 cases reported, the same number summarized in last year's chapter. One case involving school board referenda raised the interesting question of whether or not a state could…

  17. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.

    Chapter 7 of a book on school law, this chapter deals with 1979 cases involving disputes over property. Cases involving taxpayer attempts to prevent the construction of school buildings dominate this year's property chapter, as they did last year's. Yet, paradoxically, there is also a significant increase in cases in which taxpayers tried to…

  18. Property.

    ERIC Educational Resources Information Center

    Bickel, Robert D.; Zeller, Trisha A.

    A number of cases related to property issues involving institutions of higher education are examined in this chapter. Cases discussed touch on such topics as funding for property and equipment acquisition; opposition to building construction or demolition; zoning issues; building construction and equipment contracts; and lease agreements. Current…

  19. Property.

    ERIC Educational Resources Information Center

    Bickel, Robert D.; Zeller, Trisha A.

    A number of cases related to property issues involving institutions of higher education are examined in this chapter. Cases discussed touch on such topics as funding for property and equipment acquisition; opposition to building construction or demolition; zoning issues; building construction and equipment contracts; and lease agreements. Current…

  20. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.; Johnson, Margaret M.

    This chapter deals with 1981 cases involving disputes over property. Cases involving the detachment and attachment of land continue to dominate the property chapter with 11 cases reported, the same number summarized in last year's chapter. One case involving school board referenda raised the interesting question of whether or not a state could…

  1. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.

    Chapter 7 of a book on school law, this chapter deals with 1979 cases involving disputes over property. Cases involving taxpayer attempts to prevent the construction of school buildings dominate this year's property chapter, as they did last year's. Yet, paradoxically, there is also a significant increase in cases in which taxpayers tried to…

  2. Evaluated nuclear structure data file

    NASA Astrophysics Data System (ADS)

    Tuli, J. K.

    1996-02-01

    The Evaluated Nuclear Structure Data File (ENSDF) contains the evaluated nuclear properties of all known nuclides, as derived both from nuclear reaction and radioactive decay measurements. All experimental data are evaluated to create the adopted properties for each nuclide. ENSDF, together with other numeric and bibliographic files, can be accessed on-line through the INTERNET or modem, and some of the databases are also available on the World Wide Web. The structure and the scope of ENSDF are presented along with the on-line access system of the National Nuclear Data Center at Brookhaven National Laboratory.

  3. Nuclear Chemistry.

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1979

    1979-01-01

    Provides a brief review of the latest developments in nuclear chemistry. Nuclear research today is directed toward increased activity in radiopharmaceuticals and formation of new isotopes by high-energy, heavy-ion collisions. (Author/BB)

  4. Nuclear Scans

    MedlinePlus

    Nuclear scans use radioactive substances to see structures and functions inside your body. They use a special ... images. Most scans take 20 to 45 minutes. Nuclear scans can help doctors diagnose many conditions, including ...

  5. Nuclear Winter.

    ERIC Educational Resources Information Center

    Ehrlich, Anne

    1984-01-01

    "Nuclear Winter" was recently coined to describe the climatic and biological effects of a nuclear war. These effects are discussed based on models, simulations, scenarios, and projections. Effects on human populations are also considered. (JN)

  6. Nuclear Medicine

    MedlinePlus

    ... Home » Science Education » Science Topics » Nuclear Medicine SCIENCE EDUCATION SCIENCE EDUCATION Science Topics Resource Links for General Public Resource ... Related Documents: Nuclear Medicine Fact Sheet.pdf SCIENCE EDUCATION Science Topics Resource Links for General Public Resource ...

  7. Nuclear Chemistry.

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1979

    1979-01-01

    Provides a brief review of the latest developments in nuclear chemistry. Nuclear research today is directed toward increased activity in radiopharmaceuticals and formation of new isotopes by high-energy, heavy-ion collisions. (Author/BB)

  8. Nuclear Winter.

    ERIC Educational Resources Information Center

    Ehrlich, Anne

    1984-01-01

    "Nuclear Winter" was recently coined to describe the climatic and biological effects of a nuclear war. These effects are discussed based on models, simulations, scenarios, and projections. Effects on human populations are also considered. (JN)

  9. Measurement of Sedimentary Interbed Hydraulic Properties and Their Hydrologic Influence near the Idaho Nuclear Technology and Engineering Center at the Idaho National Engineering and Environmental Laboratory

    USGS Publications Warehouse

    Perkins, Kim S.

    2003-01-01

    Disposal of wastewater to unlined infiltration ponds near the Idaho Nuclear Technology and Engineering Center (INTEC), formerly known as the Idaho Chemical Processing Plant, at the Idaho National Engineering and Environmental Laboratory (INEEL) has resulted in the formation of perched water bodies in the unsaturated zone (Cecil and others, 1991). The unsaturated zone at INEEL comprises numerous basalt flows interbedded with thinner layers of coarse- to fine-grained sediments and perched ground-water zones exist at various depths associated with massive basalts, basalt-flow contacts, sedimentary interbeds, and sediment-basalt contacts. Perched ground water is believed to result from large infiltration events such as seasonal flow in the Big Lost River and wastewater discharge to infiltration ponds. Evidence from a large-scale tracer experiment conducted in 1999 near the Radioactive Waste Management Complex (RWMC), approximately 13 km from the INTEC, indicates that rapid lateral flow of perched water in the unsaturated zone may be an important factor in contaminant transport at the INEEL (Nimmo and others, 2002b). Because sedimentary interbeds, and possibly baked-zone alterations at sediment-basalt contacts (Cecil and other, 1991) play an important role in the generation of perched water it is important to assess the hydraulic properties of these units.

  10. Properties of K,Rb-intercalated C{sub 60} encapsulated inside carbon nanotubes called peapods derived from nuclear magnetic resonance

    SciTech Connect

    Mahfouz, R.; Bouhrara, M.; Kim, Y.; Wågberg, T.; Goze-Bac, C.; Abou-Hamad, E.

    2015-09-21

    We present a detailed experimental study on how magnetic and electronic properties of Rb,K-intercalated C{sub 60} encapsulated inside carbon nanotubes called peapods can be derived from {sup 13}C nuclear magnetic resonance investigations. Ring currents do play a basic role in those systems; in particular, the inner cavities of nanotubes offer an ideal environment to investigate the magnetism at the nanoscale. We report the largest diamagnetic shifts down to −68.3 ppm ever observed in carbon allotropes, which is connected to the enhancement of the aromaticity of the nanotube envelope upon intercalation. The metallization of intercalated peapods is evidenced from the chemical shift anisotropy and spin-lattice relaxation (T{sub 1}) measurements. The observed relaxation curves signal a three-component model with two slow and one fast relaxing components. We assigned the fast component to the unpaired electrons charged C{sub 60} that show a phase transition near 100 K. The two slow components can be rationalized by the two types of charged C{sub 60} at two different positions with a linear regime following Korringa behavior, which is typical for metallic system and allow us to estimate the density of sate at Fermi level n(E{sub F})

  11. 15N nuclear magnetic resonance studies of acid-base properties of pyridoxal-5'-phosphate aldimines in aqueous solution.

    PubMed

    Sharif, Shasad; Huot, Monique Chan; Tolstoy, Peter M; Toney, Michael D; Jonsson, K Hanna M; Limbach, Hans-Heinrich

    2007-04-19

    By use of 15N NMR spectroscopy, we have measured the pKa values of the aldimines 15N-(pyridoxyl-5'-phosphate-idine)-methylamine (2a), N-(pyridoxyl-5'-phosphate-15N-idine)-methylamine (2b), and 15N-(pyridoxyl-idine)-methylamine (3). These aldimines model the cofactor pyridoxal-5'-phosphate (PLP, 1) in a variety of PLP-dependent enzymes. The acid-base properties of the aldimines differ substantially from those of the free cofactor in the aldehyde form 1a or in the hydrated form 1b, which were also investigated using 15N NMR for comparison. All compounds contain three protonation sites, the pyridine ring, the phenol group, and the side chain phosphate (1, 2) or hydroxyl group (3). In agreement with the literature, 1a exhibits one of several pKas at 2.9 and 1b at 4.2. The 15N chemical shifts indicate that the corresponding deprotonation occurs partially in the pyridine and partially in the phenolic site, which compete for the remaining proton. The equilibrium constant of this ring-phenolate tautomerism was measured to be 0.40 for 1a and 0.06 for 1b. The tautomerism is essentially unaltered above pH 6.1, where the phosphate group is deprotonated to the dianion. This means that the pyridine ring is more basic than the phenolate group. Pyridine nitrogen deprotonation occurs at 8.2 for 1a and at 8.7 for 1b. By contrast, above pH 4 the phosphate site of 2 is deprotonated, while the pyridine ring pKa is 5.8. The Schiff base nitrogen does not deprotonate below pH 11.4. When the phosphate group is removed, the pKa of the Schiff base nitrogen decreases to 10.5. The phenol site cannot compete for the proton of the Schiff base nitrogen and is present in the entire pH range as a phenolate, preferentially hydrogen bonded to the solvent. The intrinsic 15N chemical shifts provide information about the hydrogen bond structures of the protonated and unprotonated species involved. Evidence is presented that the intramolecular OHN hydrogen bond of PLP aldimines is broken in aqueous

  12. Nuclear weapons, nuclear effects, nuclear war

    SciTech Connect

    Bing, G.F.

    1991-08-20

    This paper provides a brief and mostly non-technical description of the militarily important features of nuclear weapons, of the physical phenomena associated with individual explosions, and of the expected or possible results of the use of many weapons in a nuclear war. Most emphasis is on the effects of so-called ``strategic exchanges.``

  13. Nuclear Fuels.

    ERIC Educational Resources Information Center

    Nash, J. Thomas

    1983-01-01

    Trends in and factors related to the nuclear industry and nuclear fuel production are discussed. Topics addressed include nuclear reactors, survival of the U.S. uranium industry, production costs, budget cuts by the Department of Energy and U.S. Geological survey for resource studies, mining, and research/development activities. (JN)

  14. Nuclear Fuels.

    ERIC Educational Resources Information Center

    Nash, J. Thomas

    1983-01-01

    Trends in and factors related to the nuclear industry and nuclear fuel production are discussed. Topics addressed include nuclear reactors, survival of the U.S. uranium industry, production costs, budget cuts by the Department of Energy and U.S. Geological survey for resource studies, mining, and research/development activities. (JN)

  15. Spatial variability of sedimentary interbed properties near the Idaho Nuclear Technology and Engineering Center at the Idaho National Engineering and Environmental Laboratory, Idaho

    USGS Publications Warehouse

    Winfield, Kari A.

    2003-01-01

    The subsurface at the Idaho National Engineering and Environmental Laboratory (INEEL) is complex, comprised primarily of thick, fractured basalt flows interbedded with thinner sedimentary intervals. The unsaturated zone can be as thick as 200 m in the southwestern part of the INEEL. The Vadose Zone Research Park (VZRP), located approximately 10 km southwest of the Idaho Nuclear Technology and Engineering Center (INTEC), was established in 2001 to study the subsurface of a relatively undisturbed part of the INEEL. Waste percolation ponds for the INTEC were relocated to the VZRP due to concerns that perched water within the vadose zone under the original infiltration ponds (located immediately south of the INTEC) could contribute to migration of contaminants to the Snake River Plain aquifer. Knowledge of the spatial distribution of texture and hydraulic properties is important for developing a better understanding of subsurface flow processes within the interbeds, for example, by identifying low permeability layers that could lead to the formation of perched ground-water zones. Because particle-size distributions are easier to measure than hydraulic properties, particle size serves as an analog for determining how the unsaturated hydraulic properties vary both vertically within particular interbeds and laterally within the VZRP. As part of the characterization program for the subsurface at the VZRP, unsaturated and saturated hydraulic properties were measured on 10 core samples from six boreholes. Bulk properties, including particle size, bulk density, particle density, and specific surface area, were determined on material from the same depth intervals as the core samples, with an additional 66 particle- size distributions measured on bulk samples from the same boreholes. From lithologic logs of the 32 boreholes at the VZRP, three relatively thick interbeds (in places up to 10 m thick) were identified at depths of 35, 45, and 55 m below land surface. The 35-m

  16. White Paper on Nuclear Astrophysics and Low Energy Nuclear Physics - Part 1. Nuclear Astrophysics

    SciTech Connect

    Arcones, Almudena; Escher, Jutta E.; Others, M.

    2016-04-04

    This white paper informs the nuclear astrophysics community and funding agencies about the scientific directions and priorities of the field and provides input from this community for the 2015 Nuclear Science Long Range Plan. It summarizes the outcome of the nuclear astrophysics town meeting that was held on August 21 - 23, 2014 in College Station at the campus of Texas A&M University in preparation of the NSAC Nuclear Science Long Range Plan. It also reflects the outcome of an earlier town meeting of the nuclear astrophysics community organized by the Joint Institute for Nuclear Astrophysics (JINA) on October 9 - 10, 2012 Detroit, Michigan, with the purpose of developing a vision for nuclear astrophysics in light of the recent NRC decadal surveys in nuclear physics (NP2010) and astronomy (ASTRO2010). The white paper is furthermore informed by the town meeting of the Association of Research at University Nuclear Accelerators (ARUNA) that took place at the University of Notre Dame on June 12 - 13, 2014. In summary we find that nuclear astrophysics is a modern and vibrant field addressing fundamental science questions at the intersection of nuclear physics and astrophysics. These questions relate to the origin of the elements, the nuclear engines that drive life and death of stars, and the properties of dense matter. A broad range of nuclear accelerator facilities, astronomical observatories, theory efforts, and computational capabilities are needed. With the developments outlined in this white paper, answers to long-standing key questions are well within reach in the coming decade.

  17. Nuclear orientation and nuclear structure

    SciTech Connect

    Krane, K.S.

    1988-01-01

    The present generation of on-line nuclear orientation facilities promises to revolutionize the gathering of nuclear structure information, especially for the hitherto poorly known and understood nuclei far from stability. Following a brief review of the technological developments that have facilitated these experiments, the nuclear spectroscopic information that can be obtained is summarized. Applications to understanding nuclear structure are reviewed, and challenges for future studies are discussed. 14 refs., 4 figs., 3 tabs.

  18. Nuclear networking.

    PubMed

    Xie, Wei; Burke, Brian

    2017-07-04

    Nuclear lamins are intermediate filament proteins that represent important structural components of metazoan nuclear envelopes (NEs). By combining proteomics and superresolution microscopy, we recently reported that both A- and B-type nuclear lamins form spatially distinct filament networks at the nuclear periphery of mouse fibroblasts. In particular, A-type lamins exhibit differential association with nuclear pore complexes (NPCs). Our studies reveal that the nuclear lamina network in mammalian somatic cells is less ordered and more complex than that of amphibian oocytes, the only other system in which the lamina has been visualized at high resolution. In addition, the NPC component Tpr likely links NPCs to the A-type lamin network, an association that appears to be regulated by C-terminal modification of various A-type lamin isoforms. Many questions remain, however, concerning the structure and assembly of lamin filaments, as well as with their mode of association with other nuclear components such as peripheral chromatin.

  19. Concise nuclear isobar charts

    SciTech Connect

    Bucka, H.

    1986-01-01

    In the Concise Nuclear Isobar Charts, data on binding energies of protons and neutrons in the ground state and excitation energies for low-lying nuclear energy levels are displayed, both of which are of great interest for transition processes as well as for questions of nuclear structure. Also, quantum numbers for angular momentum and parity are shown for these energy levels. For the stable nuclei, data for the relative abundances, and for unstable nucleon configurations, the transition probabilities are included in the data displayed. Due to the representation chosen for the atomic nuclei, in many cases a very clear first survey of systematic properties of nuclear energy states as well as spontaneous decay processes is achieved.

  20. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.

    The author notes that controversies over construction bids and contracts continue to represent the largest number of property cases reported in this year's chapter. Most of these cases are routine disputes between colleges or universities and contractors over such issues as the return of bid bonds, recovery of additional costs for construction…

  1. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.

    Numerous cases in this year's chapter dealt with the same topics of previous years--contracts and bids for building construction, and detachment and annexation of a portion of a school district. The courts continued to attribute board discretionary authority to school boards in school property matters. Intergovernmental disputes over ownership or…

  2. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.; Forsberg, James R.

    This chapter summarizes and analyze all state supreme court and federal court decisions as well as other significant court decisions involving school property. The cases discussed are generally limited to those decided during 1974 and reported in the General Digest on or before March 1, 1975. In their discussion, the authors attempt to integrate…

  3. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.; Forsberg, James R.

    This chapter summarizes recent state supreme court and federal court decisions involving school property. The cases discussed are generally limited to those decided during 1975 and reported in the General Digest as of March 1976. In their discussion, the authors attempt to integrate related cases and to illuminate any unifying legal principles…

  4. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.

    A review of cases involving higher education property matters shows that many are concerned with building construction, equipment installation, or repair contracts. A number of other cases involve routine conflicts between colleges or universities and other governmental entities over matters such as requests for special exceptions to zoning…

  5. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.

    Numerous cases in this year's chapter dealt with the same topics of previous years--contracts and bids for building construction, and detachment and annexation of a portion of a school district. The courts continued to attribute board discretionary authority to school boards in school property matters. Intergovernmental disputes over ownership or…

  6. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.; Forsberg, James R.

    This chapter summarizes and analyze all state supreme court and federal court decisions as well as other significant court decisions involving school property. The cases discussed are generally limited to those decided during 1974 and reported in the General Digest on or before March 1, 1975. In their discussion, the authors attempt to integrate…

  7. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.

    A review of cases involving higher education property matters shows that many are concerned with building construction, equipment installation, or repair contracts. A number of other cases involve routine conflicts between colleges or universities and other governmental entities over matters such as requests for special exceptions to zoning…

  8. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.; Forsberg, James R.

    This chapter summarizes recent state supreme court and federal court decisions involving school property. The cases discussed are generally limited to those decided during 1975 and reported in the General Digest as of March 1976. In their discussion, the authors attempt to integrate related cases and to illuminate any unifying legal principles…

  9. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.

    Reflecting widespread unhappiness with the growing tax burdens in this country, the most active area of litigation reported in the property chapter this year involves various attempts by taxpayers to prevent the construction or remodeling of public school facilities. While some taxpayers fought to keep schools from being built, others in New York…

  10. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.

    The author notes that controversies over construction bids and contracts continue to represent the largest number of property cases reported in this year's chapter. Most of these cases are routine disputes between colleges or universities and contractors over such issues as the return of bid bonds, recovery of additional costs for construction…

  11. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.; Johnson, Margaret M.

    While the number of cases dealing with school property issues was significantly lower than in previous years, a significant number of cases involving the detachment and attachment of land to school districts arose. Eight of the eleven cases dealing with land detachment come from Illinois. The cases concerned requests from parents that their…

  12. Property.

    ERIC Educational Resources Information Center

    Piele, Philip K.; Forsberg, James R.

    While the types of cases reported in this year's chapter are essentially the same as those reported in last year's, the number of certain types of cases have changed--in some instances significantly. For example, the number of cases raising constitutional issues in the areas of school construction, location, and property use have declined. On the…

  13. Charge transport properties of p-CdTe/n-CdTe/n{sup +}-Si diode-type nuclear radiation detectors based on metalorganic vapor-phase epitaxy-grown epilayers

    SciTech Connect

    Niraula, M.; Yasuda, K.; Wajima, Y.; Yamashita, H.; Tsukamoto, Y.; Suzuki, Y.; Matsumoto, M.; Takai, N.; Tsukamoto, Y.; Agata, Y.

    2013-10-28

    Charge transport properties of p-CdTe/n-CdTe/n{sup +}-Si diode-type nuclear radiation detectors, fabricated by growing p-and n-type CdTe epilayers on (211) n{sup +}-Si substrates using metalorganic vapor-phase epitaxy (MOVPE), were studied by analyzing current-voltage characteristics measured at various temperatures. The diode fabricated shows good rectification properties, however, both forward and reverse biased currents deviate from their ideal behavior. The forward current exhibits typical feature of multi-step tunneling at lower biases; however, becomes space charge limited type when the bias is increased. On the other hand, the reverse current exhibits thermally activated tunneling-type current. It was found that trapping centers at the p-CdTe/n-CdTe junction, which were formed due to the growth induced defects, determine the currents of this diode, and hence limit the performance of the nuclear radiation detectors developed.

  14. Quantification of aquifer properties with surface nuclear magnetic resonance in the Platte River valley, central Nebraska, using a novel inversion method

    USGS Publications Warehouse

    Irons, Trevor P.; Hobza, Christopher M.; Steele, Gregory V.; Abraham, Jared D.; Cannia, James C.; Woodward, Duane D.

    2012-01-01

    Surface nuclear magnetic resonance, a noninvasive geophysical method, measures a signal directly related to the amount of water in the subsurface. This allows for low-cost quantitative estimates of hydraulic parameters. In practice, however, additional factors influence the signal, complicating interpretation. The U.S. Geological Survey, in cooperation with the Central Platte Natural Resources District, evaluated whether hydraulic parameters derived from surface nuclear magnetic resonance data could provide valuable input into groundwater models used for evaluating water-management practices. Two calibration sites in Dawson County, Nebraska, were chosen based on previous detailed hydrogeologic and geophysical investigations. At both sites, surface nuclear magnetic resonance data were collected, and derived parameters were compared with results from four constant-discharge aquifer tests previously conducted at those same sites. Additionally, borehole electromagnetic-induction flowmeter data were analyzed as a less-expensive surrogate for traditional aquifer tests. Building on recent work, a novel surface nuclear magnetic resonance modeling and inversion method was developed that incorporates electrical conductivity and effects due to magnetic-field inhomogeneities, both of which can have a substantial impact on the data. After comparing surface nuclear magnetic resonance inversions at the two calibration sites, the nuclear magnetic-resonance-derived parameters were compared with previously performed aquifer tests in the Central Platte Natural Resources District. This comparison served as a blind test for the developed method. The nuclear magnetic-resonance-derived aquifer parameters were in agreement with results of aquifer tests where the environmental noise allowed data collection and the aquifer test zones overlapped with the surface nuclear magnetic resonance testing. In some cases, the previously performed aquifer tests were not designed fully to characterize

  15. High-sensitivity nuclear magnetic resonance at Giga-Pascal pressures: a new tool for probing electronic and chemical properties of condensed matter under extreme conditions.

    PubMed

    Meier, Thomas; Haase, Jürgen

    2014-10-10

    Nuclear Magnetic Resonance (NMR) is one of the most important techniques for the study of condensed matter systems, their chemical structure, and their electronic properties. The application of high pressure enables one to synthesize new materials, but the response of known materials to high pressure is a very useful tool for studying their electronic structure and developing theories. For example, high-pressure synthesis might be at the origin of life; and understanding the behavior of small molecules under extreme pressure will tell us more about fundamental processes in our universe. It is no wonder that there has always been great interest in having NMR available at high pressures. Unfortunately, the desired pressures are often well into the Giga-Pascal (GPa) range and require special anvil cell devices where only very small, secluded volumes are available. This has restricted the use of NMR almost entirely in the past, and only recently, a new approach to high-sensitivity GPa NMR, which has a resonating micro-coil inside the sample chamber, was put forward. This approach enables us to achieve high sensitivity with experiments that bring the power of NMR to Giga-Pascal pressure condensed matter research. First applications, the detection of a topological electronic transition in ordinary aluminum metal and the closing of the pseudo-gap in high-temperature superconductivity, show the power of such an approach. Meanwhile, the range of achievable pressures was increased tremendously with a new generation of anvil cells (up to 10.1 GPa), that fit standard-bore NMR magnets. This approach might become a new, important tool for the investigation of many condensed matter systems, in chemistry, geochemistry, and in physics, since we can now watch structural changes with the eyes of a very versatile probe.

  16. Extracellular-signal regulated kinase 8 of Trypanosoma brucei uniquely phosphorylates its proliferating cell nuclear antigen homolog and reveals exploitable properties

    PubMed Central

    Valenciano, Ana L.; Knudsen, Giselle M.; Mackey, Zachary B.

    2016-01-01

    ABSTRACT The Trypanosoma brucei subspecies T. brucei gambiense and T. brucei rhodesiense are vector-borne pathogens that cause sleeping sickness also known as Human African Trypanosomiasis (HAT), which is fatal if left untreated. The drugs that treat HAT are ineffective and cause toxic side effects. One strategy for identifying safer and more effective HAT drugs is to therapeutically exploit essential gene targets in T. brucei. Genes that make up a basic mitogen-activated protein kinase (MAPK) network are present in T. brucei. Tb927.10.5140 encodes an essential MAPK that is homologous to the human extracellular-signal regulated kinase 8 (HsERK8) which forms a tight complex with the replication factor proliferating cell nuclear antigen (PCNA) to stabilize intracellular PCNA levels. Here we demonstrate that (TbPCNA) is uniquely phos-phorylated on serine (S) and threonine (T) residues in T. brucei and that TbERK8 phosphorylates TbPCNA at each of these residues. The ability of an ERK8 homolog to phosphorylate a PCNA homolog is a novel biochemical property that is first demonstrated here in T. brucei and may be unique to this pathogen. We demonstrate that the potent HsERK8 inhibitor Ro318220, has an IC50 for TbERK8 that is several hundred times higher than its reported IC50 for HsERK8. This indicated that the active sites of TbERK8 and HsERK8 can be selectively inhibited, which provides a rational basis for discovering inhibitors that specifically target this essential parasite MAPK to kill the parasite. PMID:27589575

  17. High-Sensitivity Nuclear Magnetic Resonance at Giga-Pascal Pressures: A New Tool for Probing Electronic and Chemical Properties of Condensed Matter under Extreme Conditions

    PubMed Central

    Meier, Thomas; Haase, Jürgen

    2014-01-01

    Nuclear Magnetic Resonance (NMR) is one of the most important techniques for the study of condensed matter systems, their chemical structure, and their electronic properties. The application of high pressure enables one to synthesize new materials, but the response of known materials to high pressure is a very useful tool for studying their electronic structure and developing theories. For example, high-pressure synthesis might be at the origin of life; and understanding the behavior of small molecules under extreme pressure will tell us more about fundamental processes in our universe. It is no wonder that there has always been great interest in having NMR available at high pressures. Unfortunately, the desired pressures are often well into the Giga-Pascal (GPa) range and require special anvil cell devices where only very small, secluded volumes are available. This has restricted the use of NMR almost entirely in the past, and only recently, a new approach to high-sensitivity GPa NMR, which has a resonating micro-coil inside the sample chamber, was put forward. This approach enables us to achieve high sensitivity with experiments that bring the power of NMR to Giga-Pascal pressure condensed matter research. First applications, the detection of a topological electronic transition in ordinary aluminum metal and the closing of the pseudo-gap in high-temperature superconductivity, show the power of such an approach. Meanwhile, the range of achievable pressures was increased tremendously with a new generation of anvil cells (up to 10.1 GPa), that fit standard-bore NMR magnets. This approach might become a new, important tool for the investigation of many condensed matter systems, in chemistry, geochemistry, and in physics, since we can now watch structural changes with the eyes of a very versatile probe. PMID:25350694

  18. Towards a Conceptual Diagnostic Survey in Nuclear Physics

    ERIC Educational Resources Information Center

    Kohnle, Antje; Mclean, Stewart; Aliotta, Marialuisa

    2011-01-01

    Understanding students' prior beliefs in nuclear physics is a first step towards improving nuclear physics instruction. This paper describes the development of a diagnostic survey in nuclear physics covering the areas of radioactive decay, binding energy, properties of the nuclear force and nuclear reactions, that was administered to students at…

  19. Towards a Conceptual Diagnostic Survey in Nuclear Physics

    ERIC Educational Resources Information Center

    Kohnle, Antje; Mclean, Stewart; Aliotta, Marialuisa

    2011-01-01

    Understanding students' prior beliefs in nuclear physics is a first step towards improving nuclear physics instruction. This paper describes the development of a diagnostic survey in nuclear physics covering the areas of radioactive decay, binding energy, properties of the nuclear force and nuclear reactions, that was administered to students at…

  20. Predictions of nuclear charge radii

    NASA Astrophysics Data System (ADS)

    Bao, M.; Lu, Y.; Zhao, Y. M.; Arima, A.

    2016-12-01

    The nuclear charge radius is a fundamental property of an atomic nucleus. In this article we study the predictive power of empirical relations for experimental nuclear charge radii of neighboring nuclei and predict the unknown charge radii of 1085 nuclei based on the experimental CR2013 database within an uncertainty of 0.03 fm.

  1. Nuclear astrophysics

    SciTech Connect

    Haxton, W.C.

    1992-01-01

    The problem of core-collapse supernovae is used to illustrate the many connections between nuclear astrophysics and the problems nuclear physicists study in terrestrial laboratories. Efforts to better understand the collapse and mantle ejection are also motivated by a variety of interdisciplinary issues in nuclear, particle, and astrophysics, including galactic chemical evolution, neutrino masses and mixing, and stellar cooling by the emission of new particles. The current status of theory and observations is summarized.

  2. Nuclear astrophysics

    SciTech Connect

    Haxton, W.C.

    1992-12-31

    The problem of core-collapse supernovae is used to illustrate the many connections between nuclear astrophysics and the problems nuclear physicists study in terrestrial laboratories. Efforts to better understand the collapse and mantle ejection are also motivated by a variety of interdisciplinary issues in nuclear, particle, and astrophysics, including galactic chemical evolution, neutrino masses and mixing, and stellar cooling by the emission of new particles. The current status of theory and observations is summarized.

  3. Nuclear Safety

    SciTech Connect

    Silver, E G

    1989-01-01

    This document is a review journal that covers significant developments in the field of nuclear safety. Its scope includes the analysis and control of hazards associated with nuclear energy, operations involving fissionable materials, and the products of nuclear fission and their effects on the environment. Primary emphasis is on safety in reactor design, construction, and operation; however, the safety aspects of the entire fuel cycle, including fuel fabrication, spent-fuel processing, nuclear waste disposal, handling of radioisotopes, and environmental effects of these operations, are also treated.

  4. Nuclear Structure at the Limits

    SciTech Connect

    Nazarewicz, Witold

    1997-12-31

    One of the frontiers of today`s nuclear science is the ``journey to the limits``: of atomic charge and nuclear mass, of neutron-to-proton ratio, and of angular momentum. The tour to the limits is not only a quest for new, exciting phenomena but the new data are expected, as well, to bring qualitatively new information about the fundamental properties of the nucleonic many-body system, the nature of the nuclear interaction, and nucleonic correlations at various energy-distance scales. In this talk, current developments in nuclear structure at the limits are discussed from a theoretical perspective.

  5. Nuclear safety

    NASA Technical Reports Server (NTRS)

    Buden, D.

    1991-01-01

    Topics dealing with nuclear safety are addressed which include the following: general safety requirements; safety design requirements; terrestrial safety; SP-100 Flight System key safety requirements; potential mission accidents and hazards; key safety features; ground operations; launch operations; flight operations; disposal; safety concerns; licensing; the nuclear engine for rocket vehicle application (NERVA) design philosophy; the NERVA flight safety program; and the NERVA safety plan.

  6. A New Look to Nuclear Data

    DOE PAGES

    McCutchan, E. A.; Brown, D. A.; Sonzogni, A. A.

    2017-03-30

    Databases of evaluated nuclear data form a cornerstone on which we build academic nuclear structure physics, reaction physics, astrophysics, and many applied nuclear technologies. In basic research, nuclear data are essential for selecting, designing and conducting experiments, and for the development and testing of theoretical models to understand the fundamental properties of atomic nuclei. Likewise, the applied fields of nuclear power, homeland security, stockpile stewardship and nuclear medicine, all have deep roots requiring evaluated nuclear data. Each of these fields requires rapid and easy access to up-to-date, comprehensive and reliable databases. The DOE-funded US Nuclear Data Program is a specificmore » and coordinated effort tasked to compile, evaluate and disseminate nuclear structure and reaction data such that it can be used by the world-wide nuclear physics community.« less

  7. Nuclear privatization

    SciTech Connect

    Jeffs, E.

    1995-11-01

    The United Kingdom government announced in May 1995 plans to privatize the country`s two nuclear generating companies, Nuclear Electric and Scottish Nuclear. Under the plan, the two companies will become operating divisions of a unified holding company, to be called British Electric, with headquarters in Scotland. Britain`s nuclear plants were left out of the initial privatization in 1989 because the government believed the financial community would be unwilling to accept the open-ended liability of decommissioning the original nine stations based on the Magnox gas-cooled reactor. Six years later, the government has found a way around this by retaining these power stations in state ownership, leaving the new nuclear company with the eight Advanced Gas-cooled Reactor (AGR) stations and the recently completed Sizewell B PWR stations. The operating Magnox stations are to be transferred to BNFL, which operates two Magnox stations of their own at Calder Hall and Chapelcross.

  8. Nuclear materials

    SciTech Connect

    Not Available

    1992-08-01

    The Department of Energy (DOE) processes plutonium for use in nuclear weapons. This fact sheet responds to your September 6, 1991, request, that we describe the methods and facilities for DOE's plutonium processing. Plutonium, which is used to make nuclear weapons, does not exist in nature and has to be produced. However, DOE no longer produces plutonium for use in nuclear weapons. Instead, DOE processes and recycles the plutonium from retired nuclear weapons and the plutonium that remains as scrap or residue from plutonium processing. This paper reports that DOE recovers plutonium through two basic processes-aqueous and pyrochemical-at four processing sites-Rocky Flats, Savannah River, Hanford, and Los Alamos. However, because of environmental and safety concerns and reductions in nuclear weapons, DOE has closed or may close most of the processing facilities. Only Los Alamos' processing facilities are currently operating.

  9. Nuclear magnetic resonance (NMR) solution structure, dynamics, and binding properties of the kringle IV type 8 module of apolipoprotein(a).

    PubMed

    Chitayat, Seth; Kanelis, Voula; Koschinsky, Marlys L; Smith, Steven P

    2007-02-20

    The plasma lipoprotein lipoprotein(a) [Lp(a)] comprises a low-density lipoprotein (LDL)-like particle covalently attached to the glycoprotein apolipoprotein(a) [apo(a)]. Apo(a) consists of multiple tandem repeating kringle modules, similar to plasminogen kringle IV (designated KIV1-KIV10), followed by modules homologous to the kringle V module and protease domain of plasminogen. The apo(a) KIV modules have been classified on the basis of their binding affinity for lysine and lysine analogues. The strong lysine-binding apo(a) KIV10 module mediates lysine-dependent interactions with fibrin and cell-surface receptors. Weak lysine-binding apo(a) KIV7 and KIV8 modules display a 2-3-fold difference in lysine affinity and play a direct role in the noncovalent step in Lp(a) assembly through binding to unique lysine-containing sequences in apolipoproteinB-100 (apoB-100). The present study describes the nuclear magnetic resonance solution structure of apo(a) KIV8 and its solution dynamics properties, the first for an apo(a) kringle module, and compares the effects of epsilon-aminocaproic acid (epsilon-ACA) binding on the backbone and side-chain conformation of KIV7 and KIV8 on a per residue basis. Apo(a) KIV8 adopts a well-ordered structure that shares the general tri-loop kringle topology with apo(a) KIV6, KIV7, and KIV10. Mapping of epsilon-ACA-induced chemical-shift changes on KIV7 and KIV8 indicate that the same residues are affected, despite a 2-3-fold difference in epsilon-ACA affinity. A unique loop conformation within KIV8, involving hydrophobic interactions with Tyr40, affects the positioning of Arg35 relative to the lysine-binding site (LBS). A difference in the orientation of the aromatic side chains comprising the hydrophobic center of the LBS in KIV8 decreases the size of the hydrophobic cleft compared to other apo(a) KIV modules. An exposed hydrophobic patch contiguous with the LBS in KIV8 and not conserved in other weak lysine-binding apo(a) kringle modules

  10. Water properties in a novel thermoswelling poly(vinyl alcohol) derivative hydrogel as studied by nuclear magnetic resonance and Fourier transform infrared spectroscopy.

    PubMed

    Wang, Jianquan; Satoh, Mitsuru

    2010-08-17

    Water properties in a novel thermoswelling hydrogel, which was prepared from poly(vinyl alcohol)-trimellitate (PVA-T) by a simple chemical cross-linking and swollen in 0.1-1.0 M Li(2)SO(4) solutions, were investigated through nuclear magnetic resonance and Fourier transform infrared (FTIR) spectroscopies. The spin-spin relaxation of the water proton in the hydrogel was measured at 5-35 degrees C, and the results were analyzed with a two-component model to obtain a long T(2) and a short T(2) as well as their fractions (f(short) = 1 - f(long)). The f(short) values thus obtained proved to be a linear function of the gel swelling ratio, and all of the data, except for an upper deviation at 1.0 M Li(2)SO(4), were found to be on an almost same line irrespective of the temperature and the salt concentration. This dependency of f(short) on the swelling degree strongly suggests that the temperature increment has an equivalent effect as that of the SO(4)(2-) concentration; namely, scission of inter(intra-)molecular hydrogen bonding (HB) between the COOHs on the side group must be responsible for the observed thermoswelling in the sulfate salt solutions. The upper deviation of f(short) at 1.0 M from the "master line" was reasonably interpreted in terms of the salting-out effect by the concentrated sulfate anion. On the other hand, attenuated total reflection-FTIR measurements for a gel plate revealed that an appreciable dissociation of the carboxyl group occurred only in the 1.0 M Li(2)SO(4) system. This finding, in turn, means that gel swelling with an increase in the salt concentration up to 0.5 M is not caused by the ionization of the gel and supports the scission of the intermolecular HB. Hydrophobic hydration around the main chain was investigated via a peak shift of the stretching vibration of -CH(2)-, and the slight red shift observed only at 1.0 M suggested that the salting-out effect onto the hydrophobic hydration is rather limited and the hydration around the main

  11. Nuclear Speckles

    PubMed Central

    Spector, David L.; Lamond, Angus I.

    2011-01-01

    Nuclear speckles, also known as interchromatin granule clusters, are nuclear domains enriched in pre-mRNA splicing factors, located in the interchromatin regions of the nucleoplasm of mammalian cells. When observed by immunofluorescence microscopy, they usually appear as 20–50 irregularly shaped structures that vary in size. Speckles are dynamic structures, and their constituents can exchange continuously with the nucleoplasm and other nuclear locations, including active transcription sites. Studies on the composition, structure, and dynamics of speckles have provided an important paradigm for understanding the functional organization of the nucleus and the dynamics of the gene expression machinery. PMID:20926517

  12. Nuclear reprogramming.

    PubMed

    Halley-Stott, Richard P; Pasque, Vincent; Gurdon, J B

    2013-06-01

    There is currently particular interest in the field of nuclear reprogramming, a process by which the identity of specialised cells may be changed, typically to an embryonic-like state. Reprogramming procedures provide insight into many mechanisms of fundamental cell biology and have several promising applications, most notably in healthcare through the development of human disease models and patient-specific tissue-replacement therapies. Here, we introduce the field of nuclear reprogramming and briefly discuss six of the procedures by which reprogramming may be experimentally performed: nuclear transfer to eggs or oocytes, cell fusion, extract treatment, direct reprogramming to pluripotency and transdifferentiation.

  13. Theoretical studies in nuclear reactions and nuclear structure. Progress report

    SciTech Connect

    Not Available

    1992-05-01

    Research in the Maryland Nuclear Theory Group focusses on problems in four basic areas of current relevance. Hadrons in nuclear matter; the structure of hadrons; relativistic nuclear physics and heavy ion dynamics and related processes. The section on hadrons in nuclear matter groups together research items which are aimed at exploring ways in which the properties of nucleons and the mesons which play a role in the nuclear force are modified in the nuclear medium. A very interesting result has been the finding that QCD sum rules supply a new insight into the decrease of the nucleon`s mass in the nuclear medium. The quark condensate, which characterizes spontaneous chiral symmetry breaking of the late QCD vacuum, decreases in nuclear matter and this is responsible for the decrease of the nucleon`s mass. The section on the structure of hadrons contains progress reports on our research aimed at understanding the structure of the nucleon. Widely different approaches are being studied, e.g., lattice gauge calculations, QCD sum rules, quark-meson models with confinement and other hedgehog models. A major goal of this type of research is to develop appropriate links between nuclear physics and QCD. The section on relativistic nuclear physics represents our continuing interest in developing an appropriate relativistic framework for nuclear dynamics. A Lorentz-invariant description of the nuclear force suggests a similar decrease of the nucleon`s mass in the nuclear medium as has been found from QCD sum rules. Work in progress extends previous successes in elastic scattering to inelastic scattering of protons by nuclei. The section on heavy ion dynamics and related processes reports on research into the e{sup +}e{sup {minus}} problem and heavy ion dynamics.

  14. Theoretical studies in nuclear reactions and nuclear structure

    SciTech Connect

    Not Available

    1992-05-01

    Research in the Maryland Nuclear Theory Group focusses on problems in four basic areas of current relevance. Hadrons in nuclear matter; the structure of hadrons; relativistic nuclear physics and heavy ion dynamics and related processes. The section on hadrons in nuclear matter groups together research items which are aimed at exploring ways in which the properties of nucleons and the mesons which play a role in the nuclear force are modified in the nuclear medium. A very interesting result has been the finding that QCD sum rules supply a new insight into the decrease of the nucleon's mass in the nuclear medium. The quark condensate, which characterizes spontaneous chiral symmetry breaking of the late QCD vacuum, decreases in nuclear matter and this is responsible for the decrease of the nucleon's mass. The section on the structure of hadrons contains progress reports on our research aimed at understanding the structure of the nucleon. Widely different approaches are being studied, e.g., lattice gauge calculations, QCD sum rules, quark-meson models with confinement and other hedgehog models. A major goal of this type of research is to develop appropriate links between nuclear physics and QCD. The section on relativistic nuclear physics represents our continuing interest in developing an appropriate relativistic framework for nuclear dynamics. A Lorentz-invariant description of the nuclear force suggests a similar decrease of the nucleon's mass in the nuclear medium as has been found from QCD sum rules. Work in progress extends previous successes in elastic scattering to inelastic scattering of protons by nuclei. The section on heavy ion dynamics and related processes reports on research into the e{sup +}e{sup {minus}} problem and heavy ion dynamics.

  15. (Nuclear theory). [Research in nuclear physics

    SciTech Connect

    Haxton, W.

    1990-01-01

    This report discusses research in nuclear physics. Topics covered in this paper are: symmetry principles; nuclear astrophysics; nuclear structure; quark-gluon plasma; quantum chromodynamics; symmetry breaking; nuclear deformation; and cold fusion. (LSP)

  16. Atlas of Nuclear Isomers

    SciTech Connect

    Jain, Ashok Kumar; Maheshwari, Bhoomika; Garg, Swati; Patial, Monika; Singh, Balraj

    2015-09-15

    We present an atlas of nuclear isomers containing the experimental data for the isomers with a half-life ≥ 10 ns together with their various properties such as excitation-energy, half-life, decay mode(s), spin-parity, energies and multipolarities of emitted gamma transitions, etc. The ENSDF database complemented by the XUNDL database has been extensively used in extracting the relevant data. Recent literature from primary nuclear physics journals, and the NSR bibliographic database have been searched to ensure that the compiled data Table is as complete and current as possible. The data from NUBASE-12 have also been checked for completeness, but as far as possible original references have been cited. Many interesting systematic features of nuclear isomers emerge, some of them new; these are discussed and presented in various graphs and figures. The cutoff date for the extraction of data from the literature is August 15, 2015.

  17. Nuclear battlefields

    SciTech Connect

    Arkin, W.M.; Fieldhouse, R.W.

    1985-01-01

    This book provides complete data on the nuclear operations and research facilities in the U.S.A., the U.S.S.R., France, China and the U.K. It describes detailed estimates on the U.S.S.R.'s nuclear stockpile for over 500 locations. It shows how non-nuclear countries cooperate with the world-wide war machine. And it maps the U.S. nuclear facilities from Little America, WY, and Charleston, SC, to the battleships patroling the world's oceans and subs stalking under the sea. The data were gathered from unclassified sources through the Freedom of Information Act, from data supplied to military installations, and from weapons source books. It provides guidance for policymakers, government and corporate officials.

  18. NUCLEAR REACTOR

    DOEpatents

    Sherman, J.; Sharbaugh, J.E.; Fauth, W.L. Jr.; Palladino, N.J.; DeHuff, P.G.

    1962-10-23

    A nuclear reactor incorporating seed and blanket assemblies is designed. Means are provided for obtaining samples of the coolant from the blanket assemblies and for varying the flow of coolant through the blanket assemblies. (AEC)

  19. Nuclear Disarmament.

    ERIC Educational Resources Information Center

    Johnson, Christopher

    1982-01-01

    Material about nuclear disarmament and the arms race should be included in secondary school curricula. Teachers can present this technical, controversial, and frightening material in a balanced and comprehensible way. Resources for instructional materials are listed. (PP)

  20. A nuclear chocolate box: the periodic table of nuclear medicine.

    PubMed

    Blower, Philip J

    2015-03-21

    Radioisotopes of elements from all parts of the periodic table find both clinical and research applications in radionuclide molecular imaging and therapy (nuclear medicine). This article provides an overview of these applications in relation to both the radiological properties of the radionuclides and the chemical properties of the elements, indicating past successes, current applications and future opportunities and challenges for inorganic chemistry.

  1. Nuclear Nonproliferation

    SciTech Connect

    Atkins-Duffin, C E

    2008-12-10

    With an explosion equivalent of about 20kT of TNT, the Trinity test was the first demonstration of a nuclear weapon. Conducted on July 16, 1945 in Alamogordo, NM this site is now a Registered National Historic Landmark. The concept and applicability of nuclear power was demonstrated on December 20, 1951 with the Experimental Breeder Reactor Number One (EBR-1) lit four light bulbs. This reactor is now a Registered National Historic Landmark, located near Arco, ID. From that moment forward it had been clearly demonstrated that nuclear energy has both peaceful and military applications and that the civilian and military fuel cycles can overlap. For the more than fifty years since the Atoms for Peace program, a key objective of nuclear policy has been to enable the wider peaceful use of nuclear energy while preventing the spread of nuclear weapons. Volumes have been written on the impact of these two actions on the world by advocates and critics; pundits and practioners; politicians and technologists. The nations of the world have woven together a delicate balance of treaties, agreements, frameworks and handshakes that are representative of the timeframe in which they were constructed and how they have evolved in time. Collectively these vehicles attempt to keep political will, nuclear materials and technology in check. This paper captures only the briefest abstract of the more significant aspects on the Nonproliferation Regime. Of particular relevance to this discussion is the special nonproliferation sensitivity associated with the uranium isotope separation and spent fuel reprocessing aspects of the nuclear fuel cycle.

  2. Nuclear Data

    SciTech Connect

    White, Morgan C.

    2014-01-23

    PowerPoint presentation targeted for educational use. Nuclear data comes from a variety of sources and in many flavors. Understanding where the data you use comes from and what flavor it is can be essential to understand and interpret your results. This talk will discuss the nuclear data pipeline with particular emphasis on providing links to additional resources that can be used to explore the issues you will encounter.

  3. Nuclear cardiac

    SciTech Connect

    Slutsky, R.; Ashburn, W.L.

    1982-01-01

    The relationship between nuclear medicine and cardiology has continued to produce a surfeit of interesting, illuminating, and important reports involving the analysis of cardiac function, perfusion, and metabolism. To simplify the presentation, this review is broken down into three major subheadings: analysis of myocardial perfusion; imaging of the recent myocardial infarction; and the evaluation of myocardial function. There appears to be an increasingly important relationship between cardiology, particularly cardiac physiology, and nuclear imaging techniques. (KRM)

  4. Nuclear accidents

    SciTech Connect

    Mobley, J.A.

    1982-05-01

    A nuclear accident with radioactive contamination can happen anywhere in the world. Because expert nuclear emergency teams may take several hours to arrive at the scene, local authorities must have a plan of action for the hours immediately following an accident. The site should be left untouched except to remove casualties. Treatment of victims includes decontamination and meticulous wound debridement. Acute radiation syndrome may be an overwhelming sequela.

  5. Nuclear telemedicine

    NASA Astrophysics Data System (ADS)

    Morrison, R. T.; Szasz, I. J.

    1990-06-01

    Diagnostic nuclear medicine patient images have been transniitted for 8 years from a regional conununity hospital to a university teaching hospital 700 kiloinetres away employing slow scan TV and telephone. Transruission and interpretation were done at the end of each working day or as circumstances required in cases of emergencies. Referring physicians received the nuclear medicine procedure report at the end of the completion day or within few minutes of completion in case of emergency procedures. To date more than 25 patient studies have been transmitted for interpretation. Blinded reinterpretation of the original hard copy data of 350 patient studies resulted in 100 agreement with the interpretation of transmitted data. This technique provides high quality diagnostic and therapeutic nuclear medicine services in remote hospitals where the services of an on-site nuclear physician is not available. 2. HISTORY Eight years ago when the nuclear medicine physician at Trail Regional Hospital left the Trail area and an other could not be recruited we examined the feasibility of image transmission by phone for interpretation since closing the department would have imposed unacceptable physical and financial hardship and medical constraints on the patient population the nearest nuclear medicine facility was at some 8 hours drive away. In hospital patients would have to be treated either based purely on physical findings or flown to Vancouver at considerable cost to the health care system (estimated cost $1500.

  6. Panel report: nuclear physics

    SciTech Connect

    Carlson, Joseph A; Hartouni, Edward P

    2010-01-01

    project Building a Universal Nuclear Energy Density Fuctional whose goals are to provide the unified approach to calculating the properties of nuclei. The successful outcome of this, and similar projects is a first steps toward a predictive nuclear theory based on fundamental interactions between constituent nucleons. The application of this theory to the domain of nuclei important for national security missions will require computational resources at the extreme scale, beyond what will be available in the near term future.

  7. Graphite for nuclear reactors

    SciTech Connect

    Virgiliev, Yu.S.; Kalyagina, I.P.

    1993-12-31

    Relative dimensional changes and physical properties of structural graphites - {Gamma}p-280 (nuclear graphite) and {Gamma}p{Pi}-2 (modificated variety of nuclear graphite for the rings of elastic contact) irradiated at temperatures ranging from 320 to 1900K with a fluence of about 2.5.10{sup 22}nvt (E {ge} 0.18 MeV) are represented. In order to ensure a long-time serviceability of the VGM - reactor blocks the high-strength graphite of {Gamma}p-1 grade are developed. The properties and its irradiation changes of {Gamma}p-1 graphite are represented. A secondary swelling of the graphite develops similar to the swelling of metals, alloys and high-melting compounds.

  8. White paper on nuclear astrophysics and low energy nuclear physics Part 1: Nuclear astrophysics

    DOE PAGES

    Arcones, Almudena; Bardayan, Dan W.; Beers, Timothy C.; ...

    2016-12-28

    This white paper informs the nuclear astrophysics community and funding agencies about the scientific directions and priorities of the field and provides input from this community for the 2015 Nuclear Science Long Range Plan. It also summarizes the outcome of the nuclear astrophysics town meeting that was held on August 21–23, 2014 in College Station at the campus of Texas A&M University in preparation of the NSAC Nuclear Science Long Range Plan. It also reflects the outcome of an earlier town meeting of the nuclear astrophysics community organized by the Joint Institute for Nuclear Astrophysics (JINA) on October 9–10, 2012more » Detroit, Michigan, with the purpose of developing a vision for nuclear astrophysics in light of the recent NRC decadal surveys in nuclear physics (NP2010) and astronomy (ASTRO2010). Our white paper is informed informed by the town meeting of the Association of Research at University Nuclear Accelerators (ARUNA) that took place at the University of Notre Dame on June 12–13, 2014. In summary we find that nuclear astrophysics is a modern and vibrant field addressing fundamental science questions at the intersection of nuclear physics and astrophysics. These questions relate to the origin of the elements, the nuclear engines that drive life and death of stars, and the properties of dense matter. A broad range of nuclear accelerator facilities, astronomical observatories, theory efforts, and computational capabilities are needed. Answers to long standing key questions are well within reach in the coming decade because of the developments outlined in this white paper.« less

  9. White paper on nuclear astrophysics and low energy nuclear physics Part 1: Nuclear astrophysics

    NASA Astrophysics Data System (ADS)

    Arcones, Almudena; Bardayan, Dan W.; Beers, Timothy C.; Bernstein, Lee A.; Blackmon, Jeffrey C.; Messer, Bronson; Brown, B. Alex; Brown, Edward F.; Brune, Carl R.; Champagne, Art E.; Chieffi, Alessandro; Couture, Aaron J.; Danielewicz, Pawel; Diehl, Roland; El-Eid, Mounib; Escher, Jutta E.; Fields, Brian D.; Fröhlich, Carla; Herwig, Falk; Hix, William Raphael; Iliadis, Christian; Lynch, William G.; McLaughlin, Gail C.; Meyer, Bradley S.; Mezzacappa, Anthony; Nunes, Filomena; O'Shea, Brian W.; Prakash, Madappa; Pritychenko, Boris; Reddy, Sanjay; Rehm, Ernst; Rogachev, Grigory; Rutledge, Robert E.; Schatz, Hendrik; Smith, Michael S.; Stairs, Ingrid H.; Steiner, Andrew W.; Strohmayer, Tod E.; Timmes, F. X.; Townsley, Dean M.; Wiescher, Michael; Zegers, Remco G. T.; Zingale, Michael

    2017-05-01

    This white paper informs the nuclear astrophysics community and funding agencies about the scientific directions and priorities of the field and provides input from this community for the 2015 Nuclear Science Long Range Plan. It summarizes the outcome of the nuclear astrophysics town meeting that was held on August 21-23, 2014 in College Station at the campus of Texas A&M University in preparation of the NSAC Nuclear Science Long Range Plan. It also reflects the outcome of an earlier town meeting of the nuclear astrophysics community organized by the Joint Institute for Nuclear Astrophysics (JINA) on October 9-10, 2012 Detroit, Michigan, with the purpose of developing a vision for nuclear astrophysics in light of the recent NRC decadal surveys in nuclear physics (NP2010) and astronomy (ASTRO2010). The white paper is furthermore informed by the town meeting of the Association of Research at University Nuclear Accelerators (ARUNA) that took place at the University of Notre Dame on June 12-13, 2014. In summary we find that nuclear astrophysics is a modern and vibrant field addressing fundamental science questions at the intersection of nuclear physics and astrophysics. These questions relate to the origin of the elements, the nuclear engines that drive life and death of stars, and the properties of dense matter. A broad range of nuclear accelerator facilities, astronomical observatories, theory efforts, and computational capabilities are needed. With the developments outlined in this white paper, answers to long standing key questions are well within reach in the coming decade.

  10. White paper on nuclear astrophysics and low energy nuclear physics Part 1: Nuclear astrophysics

    SciTech Connect

    Arcones, Almudena; Bardayan, Dan W.; Beers, Timothy C.; Bernstein, Lee A.; Blackmon, Jeffrey C.; Messer, Bronson; Brown, B. Alex; Brown, Edward F.; Brune, Carl R.; Champagne, Art E.; Chieffi, Alessandro; Couture, Aaron J.; Danielewicz, Pawel; Diehl, Roland; El-Eid, Mounib; Escher, Jutta E.; Fields, Brian D.; Fröhlich, Carla; Herwig, Falk; Hix, William Raphael; Iliadis, Christian; Lynch, William G.; McLaughlin, Gail C.; Meyer, Bradley S.; Mezzacappa, Anthony; Nunes, Filomena; O’Shea, Brian W.; Prakash, Madappa; Pritychenko, Boris; Reddy, Sanjay; Rehm, Ernst; Rogachev, Grigory; Rutledge, Robert E.; Schatz, Hendrik; Smith, Michael S.; Stairs, Ingrid H.; Steiner, Andrew W.; Strohmayer, Tod E.; Townsley, Dean M.; Wiescher, Michael; Zegers, Remco G. T.; Zingale, Michael

    2016-12-28

    This white paper informs the nuclear astrophysics community and funding agencies about the scientific directions and priorities of the field and provides input from this community for the 2015 Nuclear Science Long Range Plan. It also summarizes the outcome of the nuclear astrophysics town meeting that was held on August 21–23, 2014 in College Station at the campus of Texas A&M University in preparation of the NSAC Nuclear Science Long Range Plan. It also reflects the outcome of an earlier town meeting of the nuclear astrophysics community organized by the Joint Institute for Nuclear Astrophysics (JINA) on October 9–10, 2012 Detroit, Michigan, with the purpose of developing a vision for nuclear astrophysics in light of the recent NRC decadal surveys in nuclear physics (NP2010) and astronomy (ASTRO2010). Our white paper is informed informed by the town meeting of the Association of Research at University Nuclear Accelerators (ARUNA) that took place at the University of Notre Dame on June 12–13, 2014. In summary we find that nuclear astrophysics is a modern and vibrant field addressing fundamental science questions at the intersection of nuclear physics and astrophysics. These questions relate to the origin of the elements, the nuclear engines that drive life and death of stars, and the properties of dense matter. A broad range of nuclear accelerator facilities, astronomical observatories, theory efforts, and computational capabilities are needed. Answers to long standing key questions are well within reach in the coming decade because of the developments outlined in this white paper.

  11. Nuclear risk

    SciTech Connect

    Levenson, M.

    1989-01-01

    The title of our session, Nuclear Risk Versus Other Power Options, is provocative. It is also a title with different meanings to different people. To the utility chief executive officer, nuclear power is a high-risk financial undertaking because of political and economic barriers to cost recovery. To the utility dispatcher, it is a high-risk future power source since plant completion and start-up dates can be delayed for very long times due to uncertain legal and political issues. To the environmentalist, concerned about global effects such as greenhouse and acid rain, nuclear power is a relatively low risk energy source. To the financial people, nuclear power is a cash cow turned sour because of uncertainties as to what new plants will cost and whether they will even be allowed to operate. The statistics on risk are known and the results of probability risk assessment calculations of risks are known. The challenge is not to make nuclear power safer, it is already one of the safest, if not the safest, source of power currently available. The challenge is to find a way to communicate this to the public.

  12. Nuclear scales

    SciTech Connect

    Friar, J.L.

    1998-12-01

    Nuclear scales are discussed from the nuclear physics viewpoint. The conventional nuclear potential is characterized as a black box that interpolates nucleon-nucleon (NN) data, while being constrained by the best possible theoretical input. The latter consists of the longer-range parts of the NN force (e.g., OPEP, TPEP, the {pi}-{gamma} force), which can be calculated using chiral perturbation theory and gauged using modern phase-shift analyses. The shorter-range parts of the force are effectively parameterized by moments of the interaction that are independent of the details of the force model, in analogy to chiral perturbation theory. Results of GFMC calculations in light nuclei are interpreted in terms of fundamental scales, which are in good agreement with expectations from chiral effective field theories. Problems with spin-orbit-type observables are noted.

  13. Nuclear waste

    SciTech Connect

    Not Available

    1988-05-01

    This paper discusses how, as part of the Department of Energy's implementation of the Nuclear Waste Policy Act of 1982, DOE is required to investigate a site at Yucca Mountain, Nevada and, if it determines that the site is suitable, recommend to the President its selection for a nuclear waste repository. The Nuclear Regulatory Commission, in considering development of the plan, issued five objections, one of which is DOE's failure to recognize the range of alternative conceptual models of the Yucca Mountain site that can be supported by the limited existing technical data. At the end of the quarter DOE directed its project offices in Washington and Texas to begin orderly phase-out of all site-specific repository activities. Costs for this phase-out are $53 million for the Deaf Smith site and $85 million for the Hanford site.

  14. Nuclear pursuits

    SciTech Connect

    Not Available

    1993-05-01

    This table lists quantities of warheads (in stockpile, peak number per year, total number built, number of known test explosions), weapon development milestones (developers of the atomic bomb and hydrogen bomb, date of first operational ICBM, first nuclear-powered naval SSN in service, first MIRVed missile deployed), and testing milestones (first fission test, type of boosted fission weapon, multistage thermonuclear test, number of months from fission bomb to multistage thermonuclear bomb, etc.), and nuclear infrastructure (assembly plants, plutonium production reactors, uranium enrichment plants, etc.). Countries included in the tally are the United States, Soviet Union, Britain, France, and China.

  15. Nuclear physics: a short course

    SciTech Connect

    Hirsch, Jorge G.

    2010-09-10

    Basic properties of atomic nuclei are reviewed. Starting with the energy and length scales for microscopic processes, we go through the charge density inside the nucleus, nuclear masses and abundances, and nuclear decays. The Liquid Drop Model is presented along with some extensions. Microscopic models are introduced, with emphasis in the shell model. Alpha, beta and gamma decays are commented with some detail, including the symmetry laws which govern these decays.

  16. Nuclear winter or nuclear fall?

    NASA Astrophysics Data System (ADS)

    Berger, André

    Climate is universal. If a major modern nuclear war (i.e., with a large number of small-yield weapons) were to happen, it is not even necessary to have a specific part of the world directly involved for there to be cause to worry about the consequences for its inhabitants and their future. Indeed, smoke from fires ignited by the nuclear explosions would be transported by winds all over the world, causing dark and cold. According to the first study, by Turco et al. [1983], air surface temperature over continental areas of the northern mid-latitudes (assumed to be the nuclear war theatre) would fall to winter levels even in summer (hence the term “nuclear winter”) and induce drastic climatic conditions for several months at least. The devastating effects of a nuclear war would thus last much longer than was assumed initially. Discussing to what extent these estimations of long-term impacts on climate are reliable is the purpose of this article.

  17. Emerin plays a crucial role in nuclear invagination and in the nuclear calcium transient.

    PubMed

    Shimojima, Masaya; Yuasa, Shinsuke; Motoda, Chikaaki; Yozu, Gakuto; Nagai, Toshihiro; Ito, Shogo; Lachmann, Mark; Kashimura, Shin; Takei, Makoto; Kusumoto, Dai; Kunitomi, Akira; Hayashiji, Nozomi; Seki, Tomohisa; Tohyama, Shugo; Hashimoto, Hisayuki; Kodaira, Masaki; Egashira, Toru; Hayashi, Kenshi; Nakanishi, Chiaki; Sakata, Kenji; Yamagishi, Masakazu; Fukuda, Keiichi

    2017-03-14

    Alteration of the nuclear Ca(2+) transient is an early event in cardiac remodeling. Regulation of the nuclear Ca(2+) transient is partly independent of the cytosolic Ca(2+) transient in cardiomyocytes. One nuclear membrane protein, emerin, is encoded by EMD, and an EMD mutation causes Emery-Dreifuss muscular dystrophy (EDMD). It remains unclear whether emerin is involved in nuclear Ca(2+) homeostasis. The aim of this study is to elucidate the role of emerin in rat cardiomyocytes by means of hypertrophic stimuli and in EDMD induced pluripotent stem (iPS) cell-derived cardiomyocytes in terms of nuclear structure and the Ca(2+) transient. The cardiac hypertrophic stimuli increased the nuclear area, decreased nuclear invagination, and increased the half-decay time of the nuclear Ca(2+) transient in cardiomyocytes. Emd knockdown cardiomyocytes showed similar properties after hypertrophic stimuli. The EDMD-iPS cell-derived cardiomyocytes showed increased nuclear area, decreased nuclear invagination, and increased half-decay time of the nuclear Ca(2+) transient. An autopsied heart from a patient with EDMD also showed increased nuclear area and decreased nuclear invagination. These data suggest that Emerin plays a crucial role in nuclear structure and in the nuclear Ca(2+) transient. Thus, emerin and the nuclear Ca(2+) transient are possible therapeutic targets in heart failure and EDMD.

  18. Emerin plays a crucial role in nuclear invagination and in the nuclear calcium transient

    PubMed Central

    Shimojima, Masaya; Yuasa, Shinsuke; Motoda, Chikaaki; Yozu, Gakuto; Nagai, Toshihiro; Ito, Shogo; Lachmann, Mark; Kashimura, Shin; Takei, Makoto; Kusumoto, Dai; Kunitomi, Akira; Hayashiji, Nozomi; Seki, Tomohisa; Tohyama, Shugo; Hashimoto, Hisayuki; Kodaira, Masaki; Egashira, Toru; Hayashi, Kenshi; Nakanishi, Chiaki; Sakata, Kenji; Yamagishi, Masakazu; Fukuda, Keiichi

    2017-01-01

    Alteration of the nuclear Ca2+ transient is an early event in cardiac remodeling. Regulation of the nuclear Ca2+ transient is partly independent of the cytosolic Ca2+ transient in cardiomyocytes. One nuclear membrane protein, emerin, is encoded by EMD, and an EMD mutation causes Emery-Dreifuss muscular dystrophy (EDMD). It remains unclear whether emerin is involved in nuclear Ca2+ homeostasis. The aim of this study is to elucidate the role of emerin in rat cardiomyocytes by means of hypertrophic stimuli and in EDMD induced pluripotent stem (iPS) cell-derived cardiomyocytes in terms of nuclear structure and the Ca2+ transient. The cardiac hypertrophic stimuli increased the nuclear area, decreased nuclear invagination, and increased the half-decay time of the nuclear Ca2+ transient in cardiomyocytes. Emd knockdown cardiomyocytes showed similar properties after hypertrophic stimuli. The EDMD-iPS cell-derived cardiomyocytes showed increased nuclear area, decreased nuclear invagination, and increased half-decay time of the nuclear Ca2+ transient. An autopsied heart from a patient with EDMD also showed increased nuclear area and decreased nuclear invagination. These data suggest that Emerin plays a crucial role in nuclear structure and in the nuclear Ca2+ transient. Thus, emerin and the nuclear Ca2+ transient are possible therapeutic targets in heart failure and EDMD. PMID:28290476

  19. Nuclear astrophysics and electron beams

    SciTech Connect

    Schwenk, A.

    2013-11-07

    Electron beams provide important probes and constraints for nuclear astrophysics. This is especially exciting at energies within the regime of chiral effective field theory (EFT), which provides a systematic expansion for nuclear forces and electroweak operators based on quantum chromodynamics. This talk discusses some recent highlights and future directions based on chiral EFT, including nuclear structure and reactions for astrophysics, the neutron skin and constraints for the properties of neutron-rich matter in neutron stars and core-collapse supernovae, and the dark matter response of nuclei.

  20. Nuclear physics and particle therapy

    NASA Astrophysics Data System (ADS)

    Battistoni, G.

    2016-05-01

    The use of charged particles and nuclei in cancer therapy is one of the most successful cases of application of nuclear physics to medicine. The physical advantages in terms of precision and selectivity, combined with the biological properties of densely ionizing radiation, make charged particle approach an elective choice in a number of cases. Hadron therapy is in continuous development and nuclear physicists can give important contributions to this discipline. In this work some of the relevant aspects in nuclear physics will be reviewed, summarizing the most important directions of research and development.

  1. Comparative analysis of oncogenic properties and nuclear factor-kappaB activity of latent membrane protein 1 natural variants from Hodgkin's lymphoma's Reed-Sternberg cells and normal B-lymphocytes.

    PubMed

    Faumont, Nathalie; Chanut, Aurélie; Benard, Alan; Cogne, Nadine; Delsol, Georges; Feuillard, Jean; Meggetto, Fabienne

    2009-03-01

    In Epstein-Barr virus-associated Hodgkin's lymphomas, neoplastic Reed-Sternberg cells and surrounding non-tumor B-cells contain different variants of the LMP1-BNLF1 oncogene. In this study, we raised the question of functional properties of latent membrane protein 1 (LMP1) natural variants from both Reed-Sternberg and non-tumor B-cells. Twelve LMP1 natural variants from Reed-Sternberg cells, non-tumor B-cells of Hodgkin's lymphomas and from B-cells of benign reactive lymph nodes were cloned, sequenced and stably transfected in murine recombinant interleukin-3-dependent Ba/F3 cells to search for relationships between LMP1 cellular origin and oncogenic properties as well as nuclear factor-kappaB activation, and apoptosis protection. LMP1 variants of Reed-Sternberg cell origin were often associated with increased mutation rate and with recurrent genetic events, such as del15bp associated with S to N replacement at codon 309, and four substitutions I85L, F106Y, I122L, and M129I. Oncogenic potential (growth factor-independence plus clonogenicity) was consistently associated with LMP1 variants from Reed-Sternberg cells, but inconstantly for LMP1-variants from non-tumor B-cells. Analysis of LMP1 variants from both normal B-cells and Reed-Sternberg cells indicates that protection against apoptosis through activation of nuclear factor-kappaB - whatever the cellular origin of LMP1 - was maintained intact, regardless of the mutational pattern. Taken together, our results demonstrate that preserved nuclear factor-kappaB activity and protection against apoptosis would be the minimal prerequisites for all LMP1 natural variants from both normal and tumor cells in Hodgkin's lymphomas, and that oncogenic potential would constitute an additional feature for LMP1 natural variants in Reed-Sternberg cells.

  2. Nuclear Science.

    ERIC Educational Resources Information Center

    Pennsylvania State Dept. of Education, Harrisburg. Bureau of Curriculum Services.

    This document is a report on a course in nuclear science for the high school curriculum. The course is designed to provide a basic but comprehensive understanding of the atom in the light of modern knowledge, and to show how people attempt to harness the tremendous energy liberated through fission and fusion reactions. The course crosses what are…

  3. Nuclear Terrorism.

    SciTech Connect

    Hecker, Siegfried S.

    2001-01-01

    As pointed out by several speakers, the level of violence and destruction in terrorist attacks has increased significantly during the past decade. Fortunately, few have involved weapons of mass destruction, and none have achieved mass casualties. The Aum Shinrikyo release of lethal nerve agent, sarin, in the Tokyo subway on March 20, 1995 clearly broke new ground by crossing the threshold in attempting mass casualties with chemical weapons. However, of all weapons of mass destruction, nuclear weapons still represent the most frightening threat to humankind. Nuclear weapons possess an enormous destructive force. The immediacy and scale of destruction are unmatched. In addition to destruction, terrorism also aims to create fear among the public and governments. Here also, nuclear weapons are unmatched. The public's fear of nuclear weapons or, for that matter, of all radioactivity is intense. To some extent, this fear arises from a sense of unlimited vulnerability. That is, radioactivity is seen as unbounded in three dimensions - distance, it is viewed as having unlimited reach; quantity, it is viewed as having deadly consequences in the smallest doses (the public is often told - incorrectly, of course - that one atom of plutonium will kill); and time, if it does not kill you immediately, then it will cause cancer decades hence.

  4. Nuclear medicine

    SciTech Connect

    Wagner, H.N. Jr.

    1986-10-17

    In 1985 and 1986 nuclear medicine became more and more oriented toward in vov chemistry, chiefly as a result of advances in positron emission tomography (PET). The most important trend was the extension of PET technology into the care of patients with brain tumors, epilepsy, and heart disease. A second trend was the increasing use of single-photon emission computed tomography (SPECT).

  5. Nuclear Misinformation

    ERIC Educational Resources Information Center

    Ford, Daniel F.; Kendall, Henry W.

    1975-01-01

    Many scientists feel that research into nuclear safety has been diverted or distorted, and the results of the research concealed or inaccurately reported on a large number of occasions. Of particular concern have been the emergency cooling systems which have not, as yet, been adequately tested. (Author/MA)

  6. Nuclear Science.

    ERIC Educational Resources Information Center

    Pennsylvania State Dept. of Education, Harrisburg. Bureau of Curriculum Services.

    This document is a report on a course in nuclear science for the high school curriculum. The course is designed to provide a basic but comprehensive understanding of the atom in the light of modern knowledge, and to show how people attempt to harness the tremendous energy liberated through fission and fusion reactions. The course crosses what are…

  7. Nuclear orbiting

    SciTech Connect

    Shapira, D.

    1988-01-01

    Nuclear orbiting following collisions between sd and p shell nuclei is discussed. The dependence of this process on the real and imaginary parts of the nucleus-nucleus potential is discussed, as well as the evolution of the dinucleus toward a fully equilibrated fused system. 26 refs., 15 figs.

  8. Nuclear Misinformation

    ERIC Educational Resources Information Center

    Ford, Daniel F.; Kendall, Henry W.

    1975-01-01

    Many scientists feel that research into nuclear safety has been diverted or distorted, and the results of the research concealed or inaccurately reported on a large number of occasions. Of particular concern have been the emergency cooling systems which have not, as yet, been adequately tested. (Author/MA)

  9. Nuclear energy.

    PubMed

    Wilson, Peter D

    2010-01-01

    The technical principles and practices of the civil nuclear industry are described with particular reference to fission and its products, natural and artificial radioactivity elements principally concerned and their relationships, main types of reactor, safety issues, the fuel cycle, waste management, issues related to weapon proliferation, environmental considerations and possible future developments.

  10. NUCLEAR REACTOR

    DOEpatents

    Treshow, M.

    1961-09-01

    A boiling-water nuclear reactor is described wherein control is effected by varying the moderator-to-fuel ratio in the reactor core. This is accomplished by providing control tubes containing a liquid control moderator in the reactor core and providing means for varying the amount of control moderatcr within the control tubes.

  11. Nuclear reaction inputs based on effective interactions

    NASA Astrophysics Data System (ADS)

    Hilaire, S.; Goriely, S.; Péru, S.; Dubray, N.; Dupuis, M.; Bauge, E.

    2016-11-01

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

  12. Nuclear Fuel Cycle; (USA)

    SciTech Connect

    Cason, D.L.; Hicks, S.C.

    1991-01-01

    Nuclear Fuel Cycle (NFC) announces on a monthly basis the current worldwide information available from the open literature on all aspects of the fuel cycle except in-reactor properties and performance of fuels. More information related to radioactive waste and to the transport and storage of spent fuel is included in the current awareness publication, Radioactive Waste Management. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database (EDB) during the past month. Also included are other US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency's Technology Data Exchange, the International Atomic Energy Agency's International Nuclear Information System, or government-to-government agreements. The digests in NFC on nuclear fuel back to 1948 are available for online searching and retrieval in EDB and Nuclear Science Abstracts (NSA) database. Current information, added daily to EDB, is available to DOE and its contractors through the DOE Integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user's needs.

  13. Nuclear Mechanics in Cancer

    PubMed Central

    Denais, Celine; Lammerding, Jan

    2015-01-01

    Despite decades of research, cancer metastasis remains an incompletely understood process that is as complex as it is devastating. In recent years, there has been an increasing push to investigate the biomechanical aspects of tumorigenesis, complementing the research on genetic and biochemical changes. In contrast to the high genetic variability encountered in cancer cells, almost all metastatic cells are subject to the same physical constraints as they leave the primary tumor, invade surrounding tissues, transit through the circulatory system, and finally infiltrate new tissues. Advances in live cell imaging and other biophysical techniques, including measurements of subcellular mechanics, have yielded stunning new insights into the physics of cancer cells. While much of this research has been focused on the mechanics of the cytoskeleton and the cellular microenvironment, it is now emerging that the mechanical properties of the cell nucleus and its connection to the cytoskeleton may play a major role in cancer metastasis, as deformation of the large and stiff nucleus presents a substantial obstacle during the passage through the dense interstitial space and narrow capillaries. Here, we present an overview of the molecular components that govern the mechanical properties of the nucleus and we discuss how changes in nuclear structure and composition observed in many cancers can modulate nuclear mechanics and promote metastatic processes. Improved insights into this interplay between nuclear mechanics and metastatic progression may have powerful implications in cancer diagnostics and therapy and may reveal novel therapeutic targets for pharmacological inhibition of cancer cell invasion. PMID:24563360

  14. Structural characterization and physical properties of P2O5-CaO-Na2O-TiO2 glasses by Fourier transform infrared, Raman and solid-state magic angle spinning nuclear magnetic resonance spectroscopies.

    PubMed

    Kiani, Azadeh; Hanna, John V; King, Scott P; Rees, Gregory J; Smith, Mark E; Roohpour, Nima; Salih, Vehid; Knowles, Jonathan C

    2012-01-01

    Phosphate-based glasses have been investigated for tissue engineering applications. This study details the properties and structural characterization of titanium ultra-phosphate glasses in the 55(P(2)O(5))-30(CaO)-(25-x)(Na(2)O)-x(TiO(2)) (0≤x≤5) system, which have been prepared via melt-quenching techniques. Structural characterization was achieved by a combination of X-ray diffraction (XRD), and solid-state nuclear magnetic resonance, Raman and Fourier transform infrared spectroscopies. Physical properties were also investigated using density, degradation and ion release studies; additionally, differential thermal analysis was used for thermal analysis of these glasses. The results show that with the addition of TiO(2) the density and glass transition temperature increased whereas the degradation and ion release properties are decreased. From XRD data, TiP(2)O(7) and CaP(2)O(6) were detected in 3 and 5 mol.% TiO(2)-containing glasses. Magic angle spinning nuclear magnetic resonance results confirmed that as TiO(2) is incorporated into the glass; the amount of Q(3) increases as the amount of Q(2) consequently decreases, indicating increasing polymerization of the phosphate network. Spectroscopy results also showed that the local structure of glasses changes with increasing TiO(2) content. As TiO(2) is incorporated into the glass, the phosphate connectivity increases, indicating that the addition of TiO(2) content correlates unequivocally with an increase in glass stability. Copyright © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  15. Nuclear Medicine

    PubMed Central

    Streek, Penny Vande; Carretta, Robert; Weiland, Frederick L.

    1994-01-01

    The Council on Scientific Affairs of the California Medical Association presents the following epitomes of progress in nuclear medicine. Each item, in the judgment of a panel of knowledgeable physicians, has recently become reasonably firmly established, both as to scientific fact and clinical importance. The items are presented in simple epitome, and an authoritative reference, both to the item itself and to the subject as a whole, is generally given for those who may be unfamiliar with a particular item. The purpose is to assist busy practitioners, students, researchers, and scholars to stay abreast of progress in medicine, whether in their own field of special interest or another. The epitomes included here were selected by the Advisory Panel to the Section on Nuclear Medicine of the California Medical Association, and the summaries were prepared under the direction of Dr Lyons and the panel. PMID:7529452

  16. NUCLEAR REACTOR

    DOEpatents

    Anderson, C.R.

    1962-07-24

    A fluidized bed nuclear reactor and a method of operating such a reactor are described. In the design means are provided for flowing a liquid moderator upwardly through the center of a bed of pellets of a nentron-fissionable material at such a rate as to obtain particulate fluidization while constraining the lower pontion of the bed into a conical shape. A smooth circulation of particles rising in the center and falling at the outside of the bed is thereby established. (AEC)

  17. NUCLEAR REACTORS

    DOEpatents

    Long, E.; Ashby, J.W.

    1958-09-16

    ABS>A graphite moderator structure is presented for a nuclear reactor compriscd of an assembly of similarly orientated prismatic graphite blocks arranged on spaced longitudinal axes lying in common planes wherein the planes of the walls of the blocks are positioned so as to be twisted reintive to the planes of said axes so thatthe unlmpeded dtrect paths in direction wholly across the walls of the blocks are limited to the width of the blocks plus spacing between the blocks.

  18. NUCLEAR REACTOR

    DOEpatents

    Grebe, J.J.

    1959-07-14

    High temperature reactors which are uniquely adapted to serve as the heat source for nuclear pcwered rockets are described. The reactor is comprised essentially of an outer tubular heat resistant casing which provides the main coolant passageway to and away from the reactor core within the casing and in which the working fluid is preferably hydrogen or helium gas which is permitted to vaporize from a liquid storage tank. The reactor core has a generally spherical shape formed entirely of an active material comprised of fissile material and a moderator material which serves as a diluent. The active material is fabricated as a gas permeable porous material and is interlaced in a random manner with very small inter-connecting bores or capillary tubes through which the coolant gas may flow. The entire reactor is divided into successive sections along the direction of the temperature gradient or coolant flow, each section utilizing materials of construction which are most advantageous from a nuclear standpoint and which at the same time can withstand the operating temperature of that particular zone. This design results in a nuclear reactor characterized simultaneously by a minimum critiral size and mass and by the ability to heat a working fluid to an extremely high temperature.

  19. Nuclear waste

    SciTech Connect

    Not Available

    1991-09-01

    Radioactive waste is mounting at U.S. nuclear power plants at a rate of more than 2,000 metric tons a year. Pursuant to statute and anticipating that a geologic repository would be available in 1998, the Department of Energy (DOE) entered into disposal contracts with nuclear utilities. Now, however, DOE does not expect the repository to be ready before 2010. For this reason, DOE does not want to develop a facility for monitored retrievable storage (MRS) by 1998. This book is concerned about how best to store the waste until a repository is available, congressional requesters asked GAO to review the alternatives of continued storage at utilities' reactor sites or transferring waste to an MRS facility, GAO assessed the likelihood of an MRSA facility operating by 1998, legal implications if DOE is not able to take delivery of wastes in 1998, propriety of using the Nuclear Waste Fund-from which DOE's waste program costs are paid-to pay utilities for on-site storage capacity added after 1998, ability of utilities to store their waste on-site until a repository is operating, and relative costs and safety of the two storage alternatives.

  20. Nuclear photonics

    NASA Astrophysics Data System (ADS)

    Habs, D.; Günther, M. M.; Jentschel, M.; Thirolf, P. G.

    2012-07-01

    With the planned new γ-beam facilities like MEGa-ray at LLNL (USA) or ELI-NP at Bucharest (Romania) with 1013 γ/s and a band width of ΔEγ/Eγ≈10-3, a new era of γ beams with energies up to 20MeV comes into operation, compared to the present world-leading HIγS facility at Duke University (USA) with 108 γ/s and ΔEγ/Eγ≈3ṡ10-2. In the long run even a seeded quantum FEL for γ beams may become possible, with much higher brilliance and spectral flux. At the same time new exciting possibilities open up for focused γ beams. Here we describe a new experiment at the γ beam of the ILL reactor (Grenoble, France), where we observed for the first time that the index of refraction for γ beams is determined by virtual pair creation. Using a combination of refractive and reflective optics, efficient monochromators for γ beams are being developed. Thus, we have to optimize the total system: the γ-beam facility, the γ-beam optics and γ detectors. We can trade γ intensity for band width, going down to ΔEγ/Eγ≈10-6 and address individual nuclear levels. The term "nuclear photonics" stresses the importance of nuclear applications. We can address with γ-beams individual nuclear isotopes and not just elements like with X-ray beams. Compared to X rays, γ beams can penetrate much deeper into big samples like radioactive waste barrels, motors or batteries. We can perform tomography and microscopy studies by focusing down to μm resolution using Nuclear Resonance Fluorescence (NRF) for detection with eV resolution and high spatial resolution at the same time. We discuss the dominating M1 and E1 excitations like the scissors mode, two-phonon quadrupole octupole excitations, pygmy dipole excitations or giant dipole excitations under the new facet of applications. We find many new applications in biomedicine, green energy, radioactive waste management or homeland security. Also more brilliant secondary beams of neutrons and positrons can be produced.

  1. Nuclear photonics

    SciTech Connect

    Habs, D.; Guenther, M. M.; Jentschel, M.; Thirolf, P. G.

    2012-07-09

    With the planned new {gamma}-beam facilities like MEGa-ray at LLNL (USA) or ELI-NP at Bucharest (Romania) with 10{sup 13}{gamma}/s and a band width of {Delta}E{gamma}/E{gamma} Almost-Equal-To 10{sup -3}, a new era of {gamma} beams with energies up to 20MeV comes into operation, compared to the present world-leading HI{gamma}S facility at Duke University (USA) with 10{sup 8}{gamma}/s and {Delta}E{gamma}/E{gamma} Almost-Equal-To 3 Dot-Operator 10{sup -2}. In the long run even a seeded quantum FEL for {gamma} beams may become possible, with much higher brilliance and spectral flux. At the same time new exciting possibilities open up for focused {gamma} beams. Here we describe a new experiment at the {gamma} beam of the ILL reactor (Grenoble, France), where we observed for the first time that the index of refraction for {gamma} beams is determined by virtual pair creation. Using a combination of refractive and reflective optics, efficient monochromators for {gamma} beams are being developed. Thus, we have to optimize the total system: the {gamma}-beam facility, the {gamma}-beam optics and {gamma} detectors. We can trade {gamma} intensity for band width, going down to {Delta}E{gamma}/E{gamma} Almost-Equal-To 10{sup -6} and address individual nuclear levels. The term 'nuclear photonics' stresses the importance of nuclear applications. We can address with {gamma}-beams individual nuclear isotopes and not just elements like with X-ray beams. Compared to X rays, {gamma} beams can penetrate much deeper into big samples like radioactive waste barrels, motors or batteries. We can perform tomography and microscopy studies by focusing down to {mu}m resolution using Nuclear Resonance Fluorescence (NRF) for detection with eV resolution and high spatial resolution at the same time. We discuss the dominating M1 and E1 excitations like the scissors mode, two-phonon quadrupole octupole excitations, pygmy dipole excitations or giant dipole excitations under the new facet of

  2. iNR-PhysChem: a sequence-based predictor for identifying nuclear receptors and their subfamilies via physical-chemical property matrix.

    PubMed

    Xiao, Xuan; Wang, Pu; Chou, Kuo-Chen

    2012-01-01

    Nuclear receptors (NRs) form a family of ligand-activated transcription factors that regulate a wide variety of biological processes, such as homeostasis, reproduction, development, and metabolism. Human genome contains 48 genes encoding NRs. These receptors have become one of the most important targets for therapeutic drug development. According to their different action mechanisms or functions, NRs have been classified into seven subfamilies. With the avalanche of protein sequences generated in the postgenomic age, we are facing the following challenging problems. Given an uncharacterized protein sequence, how can we identify whether it is a nuclear receptor? If it is, what subfamily it belongs to? To address these problems, we developed a predictor called iNR-PhysChem in which the protein samples were expressed by a novel mode of pseudo amino acid composition (PseAAC) whose components were derived from a physical-chemical matrix via a series of auto-covariance and cross-covariance transformations. It was observed that the overall success rate achieved by iNR-PhysChem was over 98% in identifying NRs or non-NRs, and over 92% in identifying NRs among the following seven subfamilies: NR1--thyroid hormone like, NR2--HNF4-like, NR3--estrogen like, NR4--nerve growth factor IB-like, NR5--fushi tarazu-F1 like, NR6--germ cell nuclear factor like, and NR0--knirps like. These rates were derived by the jackknife tests on a stringent benchmark dataset in which none of protein sequences included has ≥60% pairwise sequence identity to any other in a same subset. As a user-friendly web-server, iNR-PhysChem is freely accessible to the public at either http://www.jci-bioinfo.cn/iNR-PhysChem or http://icpr.jci.edu.cn/bioinfo/iNR-PhysChem. Also a step-by-step guide is provided on how to use the web-server to get the desired results without the need to follow the complicated mathematics involved in developing the predictor. It is anticipated that iNR-PhysChem may become a useful

  3. Random matrices and chaos in nuclear physics: Nuclear structure

    SciTech Connect

    Weidenmueller, H. A.; Mitchell, G. E.

    2009-04-15

    Evidence for the applicability of random-matrix theory to nuclear spectra is reviewed. In analogy to systems with few degrees of freedom, one speaks of chaos (more accurately, quantum chaos) in nuclei whenever random-matrix predictions are fulfilled. An introduction into the basic concepts of random-matrix theory is followed by a survey over the extant experimental information on spectral fluctuations, including a discussion of the violation of a symmetry or invariance property. Chaos in nuclear models is discussed for the spherical shell model, for the deformed shell model, and for the interacting boson model. Evidence for chaos also comes from random-matrix ensembles patterned after the shell model such as the embedded two-body ensemble, the two-body random ensemble, and the constrained ensembles. All this evidence points to the fact that chaos is a generic property of nuclear spectra, except for the ground-state regions of strongly deformed nuclei.

  4. Basic Equations Interrelate Atomic and Nuclear Properties to Patterns at the Size Scales of the Cosmos, Extended Clusters of Galaxies, Galaxies, and Nebulae

    NASA Astrophysics Data System (ADS)

    Allen, Rob

    2016-09-01

    Structures within molecules and nuclei have relationships to astronomical patterns. The COBE cosmic scale plots, and large scale surveys of galaxy clusters have patterns also repeating and well known at atomic scales. The Induction, Strong Force, and Nuclear Binding Energy Periods within the Big Bang are revealed to have played roles in the formation of these large scale distributions. Equations related to the enormous patterns also model chemical bonds and likely nucleus and nucleon substructures. ratios of the forces that include gravity are accurately calculated from the distributions and shapes. In addition, particle masses and a great many physical constants can be derived with precision and accuracy from astrophysical shapes. A few very basic numbers can do modelling from nucleon internals to molecules to super novae, and up to the Visible Universe. Equations are also provided along with possible structural configurations for some Cold Dark Matter and Dark Energy.

  5. Heavy hadrons in nuclear matter

    NASA Astrophysics Data System (ADS)

    Hosaka, Atsushi; Hyodo, Tetsuo; Sudoh, Kazutaka; Yamaguchi, Yasuhiro; Yasui, Shigehiro

    2017-09-01

    Current studies on heavy hadrons in nuclear medium are reviewed with a summary of the basic theoretical concepts of QCD, namely chiral symmetry, heavy quark spin symmetry, and the effective Lagrangian approach. The nuclear matter is an interesting place to study the properties of heavy hadrons from many different points of view. We emphasize the importance of the following topics: (i) charm/bottom hadron-nucleon interaction, (ii) structure of charm/bottom nuclei, and (iii) QCD vacuum properties and hadron modifications in nuclear medium. We pick up three different groups of heavy hadrons, quarkonia (J / ψ, ϒ), heavy-light mesons (D/ D ¯ , B ¯ / B) and heavy baryons (Λc, Λb). The modifications of those hadrons in nuclear matter provide us with important information to investigate the essential properties of heavy hadrons. We also give the discussions about the heavy hadrons, not only in infinite nuclear matter, but also in finite-size atomic nuclei with finite baryon numbers, to serve future experiments.

  6. Nuclear Data Sheets for A = 207

    SciTech Connect

    Kondev, F.G.; Lalkovski, S.

    2011-03-15

    Evaluated nuclear structure and decay data for all nuclei within the A=207 mass chain are presented. The experimental data are evaluated and best values for level and gamma-ray energies, quantum numbers, lifetimes, gamma-ray intensities, and other nuclear properties are recommended. Inconsistencies and discrepancies that exist in the literature are noted. This work supersedes the earlier evaluation by M.J. Martin (1993Ma73), published in Nuclear Data Sheets70, 315 (1993).

  7. Nuclear Data Sheets for A = 216

    SciTech Connect

    Wu, S.-C.

    2007-05-15

    Evaluated spectroscopic data for all nuclei with mass number A = 216 are presented together with the relevant level schemes from radioactive decay and nuclear reaction studies. The experimental data are evaluated, inconsistencies and discrepancies are noted, and adopted values for level and {gamma}-ray energies, {gamma} intensities, as well as for other nuclear properties are given. The present evaluation supersedes the earlier one on A = 216 by A. Artna-Cohen (1997Ar04), published in Nuclear Data Sheets 80, 157 (1997)

  8. Nuclear Data Sheets for A = 206

    SciTech Connect

    Kondev, F.G.

    2008-06-15

    Evaluated nuclear structure and decay data for all nuclei within the A = 206 mass chain are presented. The experimental data are evaluated and recommended best values for level and gamma-ray energies, quantum numbers, lifetimes, gamma-ray intensities and other nuclear properties are presented. Inconsistencies and discrepancies that exist in the literature are noted. This work supersedes the earlier evaluation by E. Browne (1999Br39), published in Nuclear Data Sheets88, 29 (1999)

  9. Nuclear Data Sheets for A = 204

    SciTech Connect

    Chiara, C.J.; Kondev, F.G.

    2010-01-15

    Evaluated nuclear structure and decay data for all nuclei within the A = 204 mass chain are presented. The experimental data are evaluated and best values for level and gamma-ray energies, quantum numbers, lifetimes, gamma-ray intensities, and other nuclear properties are recommended. Inconsistencies and discrepancies that exist in the literature are noted. This work supersedes the earlier evaluation by M.R. Schmorak (1994Sc24), published in Nuclear Data Sheets72, 409 (1994)

  10. Nuclear Data Sheets for A = 146

    NASA Astrophysics Data System (ADS)

    Khazov, Yu.; Rodionov, A.; Shulyak, G.

    2016-09-01

    Evaluated nuclear structure and decay data for all nuclei within the A = 146 mass chain are presented. The experimental data are evaluated and best values for level and gamma-ray energies, quantum numbers, lifetimes, gamma-ray intensities, and other nuclear properties are recommended. Inconsistencies and discrepancies that exist in the literature are noted. This work supersedes the earlier evaluation by L.K. Peker, J.K. Tuli (1997Pe22), published in Nuclear Data Sheets82, 187 (1997).

  11. Nuclear Data Sheets for A = 133

    SciTech Connect

    Khazov, Yu.; Rodionov, A.; Kondev, F.G.

    2011-04-15

    Evaluated nuclear structure and decay data for all nuclei within the A=133 mass chain are presented. The experimental data are evaluated and best values for level and gamma-ray energies, quantum numbers, lifetimes, gamma-ray intensities, and other nuclear properties are recommended. Inconsistencies and discrepancies that exist in the literature are noted. This work supersedes the earlier evaluation by S. Raab (1995Ra12), published in Nuclear Data Sheets75, 491 (1995).

  12. Nuclear Data Sheets for A = 112

    SciTech Connect

    Lalkovski, S.; Kondev, F.G.

    2015-02-15

    Evaluated nuclear structure and decay data for all nuclei within the A = 112 mass chain are presented. The experimental data are evaluated and best values for level and gamma-ray energies, quantum numbers, lifetimes, gamma-ray intensities, and other nuclear properties are recommended. Inconsistencies and discrepancies that exist in the literature are noted. This work supersedes the earlier evaluation by D. De Frenne and E. Jacobs (1996De55), published in Nuclear Data Sheets79, 639 (1996)

  13. Global nuclear-structure calculations

    SciTech Connect

    Moeller, P.; Nix, J.R.

    1990-04-20

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

  14. Nuclear Structure at the Limits

    SciTech Connect

    Nazarewicz, W.

    1998-01-12

    One of the frontiers of today�s nuclear science is the �journey to the limits� of atomic charge and nuclear mass, of neutron-to-proton ratio, and of angular momentum. The tour to the limits is not only a quest for new, exciting phenomena, but the new data are expected, as well, to bring qualitatively new information about the fundamental properties of the nucleonic many-body system, the nature of the nuclear interaction, and nucleonic correlations at various energy-distance scales. In this series of lectures, current developments in nuclear structure at the limits are discussed from a theoretical perspective, mainly concentrating on medium-mass and heavy nuclei.

  15. Deuteron distribution in nuclear matter

    NASA Astrophysics Data System (ADS)

    Benhar, O.; Fabrocini, A.; Fantoni, S.; Illarionov, A. Yu.; Lykasov, G. I.

    2002-05-01

    We analyze the properties of deuteron-like structures in infinite, correlated nuclear matter, described by a realistic hamiltonian containing the Urbana v14 two-nucleon and the Urbana TNI many-body potentials. The distribution of neutron-proton pairs, carrying the deuteron quantum numbers, is obtained as a function of the total momentum by computing the overlap between the nuclear matter in its ground state and the deuteron wave functions in correlated basis functions theory. We study the differences between the S- and D-wave components of the deuteron and those of the deuteron-like pair in the nuclear medium. The total number of deuteron type pairs is computed and compared with the predictions of Levinger's quasideuteron model. The resulting Levinger's factor in nuclear matter at equilibrium density is 11.63. We use the local density approximation to estimate the Levinger's factor for heavy nuclei, obtaining results which are consistent with the available experimental data from photoreactions.

  16. The Nuclear Power/Nuclear Weapons Connection.

    ERIC Educational Resources Information Center

    Totten, Sam; Totten, Martha Wescoat

    1985-01-01

    Once they have nuclear power, most countries will divert nuclear materials from commercial to military programs. In excerpts from the book "Facing the Danger" (by Totten, S. and M. W., Crossing Press, 1984), five anti-nuclear activists explain how and why they have been addressing the nuclear connection. (RM)

  17. The Nuclear Power and Nuclear Weapons Connection.

    ERIC Educational Resources Information Center

    Leventhal, Paul

    1990-01-01

    Explains problems enforcing the Nuclear Non-Proliferation Treaty (NPT) of 1968. Provides factual charts and details concerning the production of nuclear energy and arms, the processing and disposal of waste products, and outlines the nuclear fuel cycle. Discusses safeguards, the risk of nuclear terrorism, and ways to deal with these problems. (NL)

  18. The Nuclear Power and Nuclear Weapons Connection.

    ERIC Educational Resources Information Center

    Leventhal, Paul

    1990-01-01

    Explains problems enforcing the Nuclear Non-Proliferation Treaty (NPT) of 1968. Provides factual charts and details concerning the production of nuclear energy and arms, the processing and disposal of waste products, and outlines the nuclear fuel cycle. Discusses safeguards, the risk of nuclear terrorism, and ways to deal with these problems. (NL)

  19. The Nuclear Power/Nuclear Weapons Connection.

    ERIC Educational Resources Information Center

    Totten, Sam; Totten, Martha Wescoat

    1985-01-01

    Once they have nuclear power, most countries will divert nuclear materials from commercial to military programs. In excerpts from the book "Facing the Danger" (by Totten, S. and M. W., Crossing Press, 1984), five anti-nuclear activists explain how and why they have been addressing the nuclear connection. (RM)

  20. Nuclear energy.

    PubMed

    Grandin, Karl; Jagers, Peter; Kullander, Sven

    2010-01-01

    Nuclear energy can play a role in carbon free production of electrical energy, thus making it interesting for tomorrow's energy mix. However, several issues have to be addressed. In fission technology, the design of so-called fourth generation reactors show great promise, in particular in addressing materials efficiency and safety issues. If successfully developed, such reactors may have an important and sustainable part in future energy production. Working fusion reactors may be even more materials efficient and environmental friendly, but also need more development and research. The roadmap for development of fourth generation fission and fusion reactors, therefore, asks for attention and research in these fields must be strengthened.

  1. Nuclear security

    SciTech Connect

    Dingell, J.D.

    1991-02-01

    The Department of Energy's (DOE) Lawrence Livermore National Laboratory, located in Livermore, California, generates and controls large numbers of classified documents associated with the research and testing of nuclear weapons. Concern has been raised about the potential for espionage at the laboratory and the national security implications of classified documents being stolen. This paper determines the extent of missing classified documents at the laboratory and assesses the adequacy of accountability over classified documents in the laboratory's custody. Audit coverage was limited to the approximately 600,000 secret documents in the laboratory's custody. The adequacy of DOE's oversight of the laboratory's secret document control program was also assessed.

  2. Nuclear dualism.

    PubMed

    Karrer, Kathleen M

    2012-01-01

    Nuclear dualism is a characteristic feature of the ciliated protozoa. Tetrahymena have two different nuclei in each cell. The larger, polyploid, somatic macronucleus (MAC) is the site of transcriptional activity in the vegetatively growing cell. The smaller, diploid micronucleus (MIC) is transcriptionally inactive in vegetative cells, but is transcriptionally active in mating cells and responsible for the genetic continuity during sexual reproduction. Although the MICs and MACs develop from mitotic products of a common progenitor and reside in a common cytoplasm, they are different from one another in almost every respect. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Laboratory determination of the mechanical, ultrasonic and hydrologic properties of welded tuff from the Grouse Canyon heated block site: Nevada Nuclear Waste Storage Investigations Project

    SciTech Connect

    Board, M.P.; Wilson, M.L.; Voegele, M.D.

    1987-08-01

    The mechanical, ultrasonic, and hydrologic properties of samples from the Grouse Canyon Member of the Belted Range Tuff exposed in the GTUF Heated Block Alcove, U12G Tunnel, Nevada Test Site are described. These results are similar to measurements made earlier at Sandia National Laboratories. 12 refs., 37 figs., 17 tabs.

  4. Nuclear Force from String Theory

    NASA Astrophysics Data System (ADS)

    Hashimoto, Koji

    2010-04-01

    Recent "technology" called holography, or gauge/string duality (AdS/CFT correspondence) found in string theory, makes it possible to compute various quantities of strongly coupled gauge theories. This technology was applied to QCD, and it was found that it describes surprisingly well important properties of low energy QCD, the hadron physics. We apply it further to nuclear physics. In this talk, I review a part of the developments of the holographic QCD, and show a computation of nuclear force at short distance, derived using the holographic QCD, which was done in collaboration with T. Sakai and S. Sugimoto [K. Hashimoto, T. Sakai, and S. Sugimoto, "Holographic Baryons: Static Properties and Form Factors from Gauge/String Duality," Prog. Theor. Phys. 120 (2008) 1093-1137, arXiv:0806.3122 [hep-th]; K. Hashimoto, T. Sakai, and S. Sugimoto, "Nuclear Force from String Theory," arXiv:0901.4449 [hep-th

  5. In situ small-angle x-ray and nuclear resonant scattering study of the evolution of structural and magnetic properties of an Fe thin film on MgO (001)

    NASA Astrophysics Data System (ADS)

    Sharma, Gagan; Gupta, Ajay; Gupta, Mukul; Schlage, Kai; Wille, H.-C.

    2015-12-01

    Growth of magnetron sputtered Fe films on clean single crystalline MgO (001) substrate has been studied using in situ grazing incidence small angle x-ray scattering (GISAXS) and grazing incidence nuclear resonant scattering (GINRS) measurements. While GISAXS provides information about morphological changes, GINRS provides information about structural and magnetic properties, thus making it possible to correlate the evolution of magnetic properties with that of morphology and structure of the film. The film exhibits a Volmer-Weber type growth, with percolation transition occurring around 2 nm film thickness. Presence of a finite quadrupole splitting, as seen in GINRS measurements, suggests a significant distortion from cubic symmetry up to a film thickness of 3.5 nm, which can be attributed to hybridization between Fe 3 d and O 2 p orbitals at the interface as well as in-plane tensile strain induced as a result of coalescence of islands. Initially Fe islands exhibit superparamagnetic relaxation, while finite magnetic moment appears upon formation of macroscopic percolation islands. The film exhibits a weak perpendicular magnetic anisotropy (PMA), which vanishes concurrently with disappearance of structural distortion, suggesting that the observed PMA at least partly originates from inherent strain in the film. No presence of any known oxide of Fe was detected at the interface. More precise information about topological and magnetic structure of the interfaces between Fe and MgO layers is obtained using combined x-ray reflectivity and nuclear resonance reflectivity measurements on a 57Fe/MgO multilayer. Measurements show that about two monolayers of Fe at the interface have a reduced hyperfine field, providing evidence for hybridization with O atoms, as predicted by theory.

  6. Nuclear Data Sheets for A = 247

    DOE PAGES

    Nesaraja, C. D.

    2015-03-01

    Here, we present available information pertaining to the nuclear structure of all nuclei with mass number A=247. Various decay and reaction data are evaluated and compared. Adopted data, levels, spin, parity and configuration assignments are given. Moreover, when there are insufficient data, expected values from systematics of nuclear properties or/and theoretical calculations are quoted. Unexpected or discrepant experimental resultsare also noted.

  7. Nuclear Data Sheets for A = 247

    SciTech Connect

    Nesaraja, C. D.

    2015-03-01

    Here, we present available information pertaining to the nuclear structure of all nuclei with mass number A=247. Various decay and reaction data are evaluated and compared. Adopted data, levels, spin, parity and configuration assignments are given. Moreover, when there are insufficient data, expected values from systematics of nuclear properties or/and theoretical calculations are quoted. Unexpected or discrepant experimental resultsare also noted.

  8. Nuclear diagnostics for inertial confinement fusion implosions

    SciTech Connect

    Murphy, T.J.

    1997-11-01

    This abstract contains viewgraphs on nuclear diagnostic techniques for inertial confinement fusion implosions. The viewgraphs contain information on: reactions of interest in ICF; advantages and disadvantages of these methods; the properties nuclear techniques can measure; and some specifics on the detectors used.

  9. Applications of nuclear physics

    DOE PAGES

    Hayes-Sterbenz, Anna Catherine

    2017-01-10

    Today the applications of nuclear physics span a very broad range of topics and fields. This review discusses a number of aspects of these applications, including selected topics and concepts in nuclear reactor physics, nuclear fusion, nuclear non-proliferation, nuclear-geophysics, and nuclear medicine. The review begins with a historic summary of the early years in applied nuclear physics, with an emphasis on the huge developments that took place around the time of World War II, and that underlie the physics involved in designs of nuclear explosions, controlled nuclear energy, and nuclear fusion. The review then moves to focus on modern applicationsmore » of these concepts, including the basic concepts and diagnostics developed for the forensics of nuclear explosions, the nuclear diagnostics at the National Ignition Facility, nuclear reactor safeguards, and the detection of nuclear material production and trafficking. The review also summarizes recent developments in nuclear geophysics and nuclear medicine. The nuclear geophysics areas discussed include geo-chronology, nuclear logging for industry, the Oklo reactor, and geo-neutrinos. The section on nuclear medicine summarizes the critical advances in nuclear imaging, including PET and SPECT imaging, targeted radionuclide therapy, and the nuclear physics of medical isotope production. Lastly, each subfield discussed requires a review article unto itself, which is not the intention of the current review; rather, the current review is intended for readers who wish to get a broad understanding of applied nuclear physics.« less

  10. Applications of nuclear physics.

    PubMed

    Hayes, A C

    2017-02-01

    Today the applications of nuclear physics span a very broad range of topics and fields. This review discusses a number of aspects of these applications, including selected topics and concepts in nuclear reactor physics, nuclear fusion, nuclear non-proliferation, nuclear-geophysics, and nuclear medicine. The review begins with a historic summary of the early years in applied nuclear physics, with an emphasis on the huge developments that took place around the time of World War II, and that underlie the physics involved in designs of nuclear explosions, controlled nuclear energy, and nuclear fusion. The review then moves to focus on modern applications of these concepts, including the basic concepts and diagnostics developed for the forensics of nuclear explosions, the nuclear diagnostics at the National Ignition Facility, nuclear reactor safeguards, and the detection of nuclear material production and trafficking. The review also summarizes recent developments in nuclear geophysics and nuclear medicine. The nuclear geophysics areas discussed include geo-chronology, nuclear logging for industry, the Oklo reactor, and geo-neutrinos. The section on nuclear medicine summarizes the critical advances in nuclear imaging, including PET and SPECT imaging, targeted radionuclide therapy, and the nuclear physics of medical isotope production. Each subfield discussed requires a review article unto itself, which is not the intention of the current review; rather, the current review is intended for readers who wish to get a broad understanding of applied nuclear physics.

  11. Applications of nuclear physics

    NASA Astrophysics Data System (ADS)

    Hayes, A. C.

    2017-02-01

    Today the applications of nuclear physics span a very broad range of topics and fields. This review discusses a number of aspects of these applications, including selected topics and concepts in nuclear reactor physics, nuclear fusion, nuclear non-proliferation, nuclear-geophysics, and nuclear medicine. The review begins with a historic summary of the early years in applied nuclear physics, with an emphasis on the huge developments that took place around the time of World War II, and that underlie the physics involved in designs of nuclear explosions, controlled nuclear energy, and nuclear fusion. The review then moves to focus on modern applications of these concepts, including the basic concepts and diagnostics developed for the forensics of nuclear explosions, the nuclear diagnostics at the National Ignition Facility, nuclear reactor safeguards, and the detection of nuclear material production and trafficking. The review also summarizes recent developments in nuclear geophysics and nuclear medicine. The nuclear geophysics areas discussed include geo-chronology, nuclear logging for industry, the Oklo reactor, and geo-neutrinos. The section on nuclear medicine summarizes the critical advances in nuclear imaging, including PET and SPECT imaging, targeted radionuclide therapy, and the nuclear physics of medical isotope production. Each subfield discussed requires a review article unto itself, which is not the intention of the current review; rather, the current review is intended for readers who wish to get a broad understanding of applied nuclear physics.

  12. High-spin nuclear spectroscopy

    SciTech Connect

    Diamond, R.M.

    1986-07-01

    High-spin spectroscopy is the study of the changes in nuclear structure, properties, and behavior with increasing angular momentum. It involves the complex interplay between collective and single-particle motion, between shape and deformation changes, particle alignments, and changes in the pairing correlations. A review of progress in theory, experimentation, and instrumentation in this field is given. (DWL)

  13. Triaxially deformed relativistic point-coupling model for Λ hypernuclei: A quantitative analysis of the hyperon impurity effect on nuclear collective properties

    NASA Astrophysics Data System (ADS)

    Xue, W. X.; Yao, J. M.; Hagino, K.; Li, Z. P.; Mei, H.; Tanimura, Y.

    2015-02-01

    Background: The impurity effect of hyperons on atomic nuclei has received a renewed interest in nuclear physics since the first experimental observation of appreciable reduction of E 2 transition strength in low-lying states of the hypernucleus Λ7Li . Many more data on low-lying states of Λ hypernuclei will be measured soon for s d -shell nuclei, providing good opportunities to study the Λ impurity effect on nuclear low-energy excitations. Purpose: We carry out a quantitative analysis of the Λ hyperon impurity effect on the low-lying states of s d -shell nuclei at the beyond-mean-field level based on a relativistic point-coupling energy density functional (EDF), considering that the Λ hyperon is injected into the lowest positive-parity (Λs) and negative-parity (Λp) states. Method: We adopt a triaxially deformed relativistic mean-field (RMF) approach for hypernuclei and calculate the Λ binding energies of hypernuclei as well as the potential-energy surfaces (PESs) in the (β ,γ ) deformation plane. We also calculate the PESs for the Λ hypernuclei with good quantum numbers by using a microscopic particle rotor model (PRM) with the same relativistic EDF. The triaxially deformed RMF approach is further applied in order to determine the parameters of a five-dimensional collective Hamiltonian (5DCH) for the collective excitations of triaxially deformed core nuclei. Taking 25,27Mg Λ and Si31Λ as examples, we analyze the impurity effects of Λs and Λp on the low-lying states of the core nuclei. Results: We show that Λs increases the excitation energy of the 21+ state and decreases the E 2 transition strength from this state to the ground state by 12 %to17 % . On the other hand, Λp tends to develop pronounced energy minima with larger deformation, although it modifies the collective parameters in such a way that the collectivity of the core nucleus can be either increased or decreased. Conclusions: The quadrupole deformation significantly affects the

  14. HTGR Base Technology Program. Task 2: concrete properties in nuclear environment. A review of concrete material systems for application to prestressed concrete pressure vessels

    SciTech Connect

    Naus, D.J.

    1981-05-01

    Prestressed concrete pressure vessels (PCPVs) are designed to serve as primary pressure containment structures. The safety of these structures depends on a correct assessment of the loadings and proper design of the vessels to accept these loadings. Proper vessel design requires a knowledge of the component (material) properties. Because concrete is one of the primary constituents of PCPVs, knowledge of its behavior is required to produce optimum PCPV designs. Concrete material systems are reviewed with respect to constituents, mix design, placing, curing, and strength evaluations, and typical concrete property data are presented. Effects of extreme loadings (elevated temperature, multiaxial, irradiation) on concrete behavior are described. Finally, specialty concrete material systems (high strength, fibrous, polymer, lightweight, refractory) are reviewed. 235 references.

  15. Nuclear Fuel Cycle: a current awareness bulletin

    SciTech Connect

    McLaren, L.H.

    1985-01-15

    Nuclear Fuel Cycle announces on a semimonthly basis the current worldwide information available on all aspects of fuel cycle except in-reactor properties and fuel performance and the management of radioactive wastes.

  16. Nuclear data sheets for A = 210

    SciTech Connect

    Harmatz, B.

    1981-01-01

    Nuclear structure information pertaining to A = 210 has been reviewed. The level properties obtained from decay and reaction experiments are shown in the drawings. Experimental methods, references, and comment are given in the text.

  17. Nuclear Technology Programs

    SciTech Connect

    Harmon, J.E.

    1990-10-01

    This document reports on the work done by the Nuclear Technology Programs of the Chemical Technology Division, Argonne National Laboratory, in the period April--September 1988. These programs involve R D in three areas: applied physical chemistry, separation science and technology, and nuclear waste management. The work in applied physical chemistry includes investigations into the processes that control the release and transport of fission products under accident-like conditions, the thermophysical properties of selected materials in environments simulating those of fusion energy systems. In the area of separation science and technology, the bulk of the effort is concerned with developing and implementing processes for the removal and concentration of actinides from waste streams contaminated by transuranic elements. Another effort is concerned with examining the feasibility of substituting low-enriched for high-enriched uranium in the production of fission-product {sup 99}Mo. In the area of waste management, investigations are underway on the performance of materials in projected nuclear repository conditions to provide input to the licensing of the nation's high-level waste repositories.

  18. Nuclear and particle astrophysics

    SciTech Connect

    Glendenning, N.K.

    1990-10-31

    We discuss the physics of matter that is relevant to the structure of compact stars. This includes nuclear, neutron star matter and quark matter and phase transitions between them. Many aspects of neutron star structure and its dependance on a number of physical assumptions about nuclear matter properties and hyperon couplings are investigated. We also discuss the prospects for obtaining constraints on the equation of state from astrophysical sources. Neuron star masses although few are known at present, provide a very direct constraint in as much as the connection to the equation of state involves only the assumption that Einstein's general of theory of relativity is correct at the macroscopic scale. Supernovae simulations involve such a plethora of physical processes including those involved in the evolution of the precollapse configuration, not all of them known or understood, that they provide no constraint at the present time. Indeed the prompt explosion, from which a constraint had been thought to follow, is now believed not to be mechanism by which most, if any stars, explode. In any case the nuclear equation of state is but one of a multitude on uncertain factors, and possibly one of the least important. The rapid rotation of pulsars is also discussed. It is shown that for periods below a certain limit it becomes increasingly difficult to reconcile them with neutron stars. Strange stars are possible if strange matter is the absolute ground state. We discuss such stars and their compatibility with observation. 112 refs., 37 figs., 6 tabs.

  19. Properties and behavior of the platinum group metals in the glass resulting from the vitrification of simulated nuclear fuel reprocessing waste

    SciTech Connect

    Krause, C. ); Luckscheiter, B. )

    1991-12-01

    Two types of platinum group metal particles were found in borosilicate nuclear waste glasses: needle-shaped RuO{sub 2} particles and spherical PdRh{sub {ital x}}Te{sub {ital y}} alloys. They form a dense sediment of high electrical conductivity and relatively high viscosity at the bottom of the ceramic melting furnace. The sludge shows a non-Newtonian flow behavior. The viscosity and conductivity of the sludge depend not only on the platinum group metal content but also on the texture and morphology of the RuO{sub 2} particles. RuO{sub 2} forms long, needle-shaped crystals which are caused by alkalimolybdate salt melts that formed in the calcine layer. The salt melts oxidize the Ru present as small RuO{sub 2} particles after calcination to higher oxidation states. Ruthenium (VI) compounds are formed, presumably, which are not stable with respect to RuO{sub 2} under the melting conditions. RuO{sub 2} precipitates and crystallizes into long, needle-like particles.

  20. Nuclear Data Sheets for A=69

    SciTech Connect

    Nesaraja, Caroline D

    2014-01-01

    Experimental data on ground- and excited-state properties for all known nuclei with mass number A=69 have been compiled and evaluated. States populated in radioactive decay, as well as in nuclear reactions, have been considered. For these nuclei, level and decay schemes, as well as tables of nuclear properties, are given in detail. This work supersedes the 2000 evaluation by M.R.Bhat and J.K.Tuli (2000Bh05).

  1. NUCLEAR REACTOR

    DOEpatents

    Grebe, J.J.

    1959-12-15

    A reactor which is particularly adapted tu serve as a heat source for a nuclear powered alrcraft or rocket is described. The core of this reactor consists of a porous refractory modera;or body which is impregnated with fissionable nuclei. The core is designed so that its surface forms tapered inlet and outlet ducts which are separated by the porous moderator body. In operation a gaseous working fluid is circulated through the inlet ducts to the surface of the moderator, enters and passes through the porous body, and is heated therein. The hot gas emerges into the outlet ducts and is available to provide thrust. The principle advantage is that tremendous quantities of gas can be quickly heated without suffering an excessive pressure drop.

  2. NUCLEAR REACTOR

    DOEpatents

    Christy, R.F.

    1958-07-15

    A nuclear reactor of the homogeneous liquid fuel type is described wherein the fissionable isotope is suspended or dissolved in a liquid moderator such as water. The reactor core is comprised essentially of a spherical vessel for containing the reactive composition surrounded by a reflector, preferably of beryllium oxide. The reactive composition may be an ordinary water solution of a soluble salt of uranium, the quantity of fissionable isotope in solution being sufficient to provide a critical mass in the vessel. The liquid fuel is stored in a tank of non-crtttcal geometry below the reactor vessel and outside of the reflector and is passed from the tank to the vessel through a pipe connecting the two by air pressure means. Neutron absorbing control and safety rods are operated within slots in the reflector adjacent to the vessel.

  3. Nuclear reactor

    DOEpatents

    Wade, Elman E.

    1979-01-01

    A nuclear reactor including two rotatable plugs and a positive top core holddown structure. The top core holddown structure is divided into two parts: a small core cover, and a large core cover. The small core cover, and the upper internals associated therewith, are attached to the small rotating plug, and the large core cover, with its associated upper internals, is attached to the large rotating plug. By so splitting the core holddown structures, under-the-plug refueling is accomplished without the necessity of enlarging the reactor pressure vessel to provide a storage space for the core holddown structure during refueling. Additionally, the small and large rotating plugs, and their associated core covers, are arranged such that the separation of the two core covers to permit rotation is accomplished without the installation of complex lifting mechanisms.

  4. NUCLEAR REACTOR

    DOEpatents

    Miller, H.I.; Smith, R.C.

    1958-01-21

    This patent relates to nuclear reactors of the type which use a liquid fuel, such as a solution of uranyl sulfate in ordinary water which acts as the moderator. The reactor is comprised of a spherical vessel having a diameter of about 12 inches substantially surrounded by a reflector of beryllium oxide. Conventionnl control rods and safety rods are operated in slots in the reflector outside the vessel to control the operation of the reactor. An additional means for increasing the safety factor of the reactor by raising the ratio of delayed neutrons to prompt neutrons, is provided and consists of a soluble sulfate salt of beryllium dissolved in the liquid fuel in the proper proportion to obtain the result desired.

  5. Determination of the physical and chemical properties, biokinetics, and dose coefficients of uranium compounds handled during nuclear fuel fabrication in France.

    PubMed

    Ansoborlo, E; Chazel, V; Hengé-Napoli, M H; Pihet, P; Rannou, A; Bailey, M R; Stradling, N

    2002-03-01

    The introduction of new ICRP recommendations, especially the new Human Respiratory Tract Model (HRTM) in ICRP Publication 66 led us to focus on some specific parameters related to industrial uranium aerosols collected between 1990 and 1999 at French nuclear fuel fabrication facilities operated by COGEMA, FBFC, and the CEA. Among these parameters, the activity median aerodynamic diameter (AMAD), specific surface area (SSA), and parameters describing absorption to blood f(r), s(r) and s(s) defined in ICRP Publication 66 were identified as the most relevant influencing dose assessment. This study reviewed the data for 25 pure and impure uranium compounds. The average value of AMAD obtained was 5.7 microm (range 1.1-8.5 microm), which strongly supports the choice of 5 microm as the default value of AMAD for occupational exposures. The SSA varied between 0.4 and 18.3 m2 g(-1). For most materials, values of the absorption parameters f(r), s(r), and s(s) derived from the in vitro experiments were generally consistent with those derived from the in vivo experiments. Using average values for each pure compound allowed us to classify UO2 and U3O8 as Type S, mixed oxides, UF4, UO3 and ADU as Type M, and UO4 as Type F based on the ICRP Publication 71 criteria. Dose coefficients were also calculated for each pure compound, and average values for each type of pure compound were compared with those derived using default values. Finally, the lung retention kinetics and urinary excretion rates for inhaled U03 were compared using material-specific and default absorption parameters, in order to give a practical example of the application of this study.

  6. Nuclear resonance vibrational spectroscopy reveals the FeS cluster composition and active site vibrational properties of an O2-tolerant NAD+-reducing [NiFe] hydrogenase

    DOE PAGES

    Lauterbach, Lars; Wang, Hongxin; Horch, Marius; ...

    2014-10-30

    Hydrogenases are complex metalloenzymes that catalyze the reversible splitting of molecular hydrogen into protons and electrons essentially without overpotential. The NAD+-reducing soluble hydrogenase (SH) from Ralstonia eutropha is capable of H2 conversion even in the presence of usually toxic dioxygen. The molecular details of the underlying reactions are largely unknown, mainly because of limited knowledge of the structure and function of the various metal cofactors present in the enzyme. Here, all iron-containing cofactors of the SH were investigated by 57Fe specific nuclear resonance vibrational spectroscopy (NRVS). Our data provide experimental evidence for one [2Fe2S] center and four [4Fe4S] clusters, whichmore » is consistent with the amino acid sequence composition. Only the [2Fe2S] cluster and one of the four [4Fe4S] clusters were reduced upon incubation of the SH with NADH. This finding explains the discrepancy between the large number of FeS clusters and the small amount of FeS cluster-related signals as detected by electron paramagnetic resonance spectroscopic analysis of several NAD+-reducing hydrogenases. For the first time, Fe–CO and Fe–CN modes derived from the [NiFe] active site could be distinguished by NRVS through selective 13C labeling of the CO ligand. This strategy also revealed the molecular coordinates that dominate the individual Fe–CO modes. The present approach explores the complex vibrational signature of the Fe–S clusters and the hydrogenase active site, thereby showing that NRVS represents a powerful tool for the elucidation of complex biocatalysts containing multiple cofactors.« less

  7. Hydride reorientation and its impact on ambient temperature mechanical properties of high burn-up irradiated and unirradiated recrystallized Zircaloy-2 nuclear fuel cladding with an inner liner

    NASA Astrophysics Data System (ADS)

    Auzoux, Q.; Bouffioux, P.; Machiels, A.; Yagnik, S.; Bourdiliau, B.; Mallet, C.; Mozzani, N.; Colas, K.

    2017-10-01

    Precipitation of radial hydrides in zirconium-based alloy cladding concomitant with the cooling of spent nuclear fuel during dry storage can potentially compromise cladding integrity during its subsequent handling and transportation. This paper investigates hydride reorientation and its impact on ductility in unirradiated and irradiated recrystallized Zircaloy-2 cladding with an inner liner (cladding for boiling water reactors) subjected to hydride reorientation treatments. Cooling from 400 °C, hydride reorientation occurs in recrystallized Zircaloy-2 with liner at a lower effective stress in irradiated samples (below 40 MPa) than in unirradiated specimens (between 40 and 80 MPa). Despite significant hydride reorientation, unirradiated recrystallized Zircaloy-2 with liner cladding containing ∼200 wppm hydrogen shows a high diametral strain at fracture (>15%) during burst tests at ambient temperature. This ductile behavior is due to (1) the lower yield stress of the recrystallized cladding materials in comparison to hydride fracture strength (corrected by the compression stress arising from the precipitation) and (2) the hydride or hydrogen-depleted zone as a result of segregation of hydrogen into the liner layer. In irradiated Zircaloy-2 with liner cladding containing ∼340 wppm hydrogen, the conservation of some ductility during ring tensile tests at ambient temperature after reorientation treatment at 400 °C with cooling rates of ∼60 °C/h is also attributed to the existence of a hydride-depleted zone. Treatments at lower cooling rates (∼6 °C/h and 0.6 °C/h) promote greater levels of hydrogen segregation into the liner and allow for increased irradiation defect annealing, both of which result in a significant increase in ductility. Based on this investigation, given the very low cooling rates typical of dry storage systems, it can be concluded that the thermal transients associated with dry storage should not degrade, and more likely should actually

  8. Ligand design for alkali-metal-templated self-assembly of unique high-nuclearity CuII aggregates with diverse coordination cage units: crystal structures and properties.

    PubMed

    Du, Miao; Bu, Xian-He; Guo, Ya-Mei; Ribas, Joan

    2004-03-19

    The construction of two unique, high-nuclearity Cu(II) supramolecular aggregates with tetrahedral or octahedral cage units, [(mu(3)-Cl)[Li subset Cu(4)(mu-L(1))(3)](3)](ClO(4))(8)(H(2)O)(4.5) (1) and [[Na(2) subset Cu(12)(mu-L(2))(8)(mu-Cl)(4)](ClO(4))(8)(H(2)O)(10)(H(3)O(+))(2)](infinity) (2) by alkali-metal-templated (Li(+) or Na(+)) self-assembly, was achieved by the use of two newly designed carboxylic-functionalized diazamesocyclic ligands, N,N'-bis(3-propionyloxy)-1,4-diazacycloheptane (H(2)L(1)) or 1,5-diazacyclooctane-N,N'-diacetate acid (H(2)L(2)). Complex 1 crystallizes in the trigonal R3c space group (a = b = 20.866(3), c = 126.26(4) A and Z = 12), and 2 in the triclinic P1 space group (a = 13.632(4), b = 14.754(4), c = 19.517(6) A, alpha = 99.836(6), beta = 95.793(5), gamma = 116.124(5) degrees and Z = 1). By subtle variation of the ligand structures and the alkali-metal templates, different polymeric motifs were obtained: a dodecanuclear architecture 1 consisting of three Cu(4) tetrahedral cage units with a Li(+) template, and a supramolecular chain 2 consisting of two crystallographically nonequivalent octahedral Cu(6) polyhedra with a Na(+) template. The effects of ligand functionality and alkali metal template ions on the self-assembly processes of both coordination supramolecular aggregates, and their magnetic behaviors are discussed in detail.

  9. Structures and Properties of Silicate Glasses and Melts at High Pressure: Multi-nuclear 2 Dimensional Solid State NMR and Statistical Mechanical Modeling

    NASA Astrophysics Data System (ADS)

    Lee, S.; Fei, Y.; Cody, G. D.; Mysen, B. O.

    2003-12-01

    Essential to the transport and thermodynamic properties of silicates at high pressure is the full understanding of atomic arrangement of system under pressure. Whereas there have been significant progresses in our understanding of the atomic structures of crystalline materials or molecules at high pressure, much less is known about the structures of amorphous silicates including glasses and melts. This is largely because conventional X-rays or optical spectroscopy can only provide limited information of the various aspects of atomic disorder in densified amorphous silicates. Recent development and advances of 2 dimensional solid state NMR have offered much improved resolution, allowing us to probe structural details of amorphous silicates (Lee, Fei, Cody, & Mysen, Geophys. Res. Lett., 2003, 30, 1845; Lee and Stebbins, J. Phys. Chem. B., 2003, 107, 3141). Here we present recent 2D NMR (MQMAS) spectra of silicate glasses, quenched from melts at 6-15 GPa in a multi-anvil apparatus at Geophysical Laboratory, which reveals previously unknown details of melt structures at high pressure. The atomic structures of model glasses at high pressure are significantly different from those at ambient pressure and show evidence of extensive chemical ordering among highly coordinated network polyhedra, such as [5,6]Al and [5,6]Si, which affects corresponding macroscopic properties. New oxygen sites in serious of sodium silicate and aluminosilicate glasses with varying degree of polymerization at high pressure include [5,6]Al-O-[4]Si, [5,6]Si-O-[4]Si and Na-O-[5,6]Si. The fractions of these sites increase with increasing pressure mainly at the expanse of Na-O-[4]Si. The fraction of [5,6]Al in aluminosilicate glasses increases with pressure, but decreases with increasing degree of polymerization of melts from (Na2O)0.75(Al2O3)0.253SiO2 to NaAlSi3O8 at constant pressure. The effect of these structural changes and chemical ordering to the diffusivity and configurational thermodynamic

  10. Nuclear Education Update.

    ERIC Educational Resources Information Center

    Winter, Metta L.

    1986-01-01

    Addresses the controversial issue of nuclear education in public schools. Highlights include resolutions passed by the National Congress of Parent Teacher Associations, what nuclear education is, distinction between nuclear education and education in the nuclear age, educational materials, a review of teaching materials, nuclear literacy, and…

  11. Nuclear Education Update.

    ERIC Educational Resources Information Center

    Winter, Metta L.

    1986-01-01

    Addresses the controversial issue of nuclear education in public schools. Highlights include resolutions passed by the National Congress of Parent Teacher Associations, what nuclear education is, distinction between nuclear education and education in the nuclear age, educational materials, a review of teaching materials, nuclear literacy, and…

  12. Nuclear reactions from lattice QCD

    DOE PAGES

    Briceño, Raúl A.; Davoudi, Zohreh; Luu, Thomas C.

    2015-01-13

    In this study, one of the overarching goals of nuclear physics is to rigorously compute properties of hadronic systems directly from the fundamental theory of strong interactions, Quantum Chromodynamics (QCD). In particular, the hope is to perform reliable calculations of nuclear reactions which will impact our understanding of environments that occur during big bang nucleosynthesis, the evolution of stars and supernovae, and within nuclear reactors and high energy/density facilities. Such calculations, being truly ab initio, would include all two-nucleon and three- nucleon (and higher) interactions in a consistent manner. Currently, lattice QCD provides the only reliable option for performing calculationsmore » of some of the low-energy hadronic observables. With the aim of bridging the gap between lattice QCD and nuclear many-body physics, the Institute for Nuclear Theory held a workshop on Nuclear Reactions from Lattice QCD on March 2013. In this review article, we report on the topics discussed in this workshop and the path planned to move forward in the upcoming years.« less

  13. Nuclear reactions from lattice QCD

    SciTech Connect

    Briceño, Raúl A.; Davoudi, Zohreh; Luu, Thomas C.

    2015-01-13

    In this study, one of the overarching goals of nuclear physics is to rigorously compute properties of hadronic systems directly from the fundamental theory of strong interactions, Quantum Chromodynamics (QCD). In particular, the hope is to perform reliable calculations of nuclear reactions which will impact our understanding of environments that occur during big bang nucleosynthesis, the evolution of stars and supernovae, and within nuclear reactors and high energy/density facilities. Such calculations, being truly ab initio, would include all two-nucleon and three- nucleon (and higher) interactions in a consistent manner. Currently, lattice QCD provides the only reliable option for performing calculations of some of the low-energy hadronic observables. With the aim of bridging the gap between lattice QCD and nuclear many-body physics, the Institute for Nuclear Theory held a workshop on Nuclear Reactions from Lattice QCD on March 2013. In this review article, we report on the topics discussed in this workshop and the path planned to move forward in the upcoming years.

  14. Nuclear reactions from lattice QCD

    NASA Astrophysics Data System (ADS)

    Briceño, Raúl A.; Davoudi, Zohreh; Luu, Thomas C.

    2015-02-01

    One of the overarching goals of nuclear physics is to rigorously compute properties of hadronic systems directly from the fundamental theory of strong interactions, quantum chromodynamics (QCD). In particular, the hope is to perform reliable calculations of nuclear reactions which will impact our understanding of environments that occur during big bang nucleosynthesis, the evolution of stars and supernovae, and within nuclear reactors and high energy/density facilities. Such calculations, being truly ab initio, would include all two-nucleon and three-nucleon (and higher) interactions in a consistent manner. Currently, lattice quantum chromodynamics (LQCD) provides the only reliable option for performing calculations of some of the low-energy hadronic observables. With the aim of bridging the gap between LQCD and nuclear many-body physics, the Institute for Nuclear Theory held a workshop on Nuclear Reactions from LQCD on March 2013. In this review article, we report on the topics discussed in this workshop and the path planned to move forward in the upcoming years.

  15. Nuclear waste forms for actinides.

    PubMed

    Ewing, R C

    1999-03-30

    The disposition of actinides, most recently 239Pu from dismantled nuclear weapons, requires effective containment of waste generated by the nuclear fuel cycle. Because actinides (e.g., 239Pu and 237Np) are long-lived, they have a major impact on risk assessments of geologic repositories. Thus, demonstrable, long-term chemical and mechanical durability are essential properties of waste forms for the immobilization of actinides. Mineralogic and geologic studies provide excellent candidate phases for immobilization and a unique database that cannot be duplicated by a purely materials science approach. The "mineralogic approach" is illustrated by a discussion of zircon as a phase for the immobilization of excess weapons plutonium.

  16. Nuclear spectroscopic studies. Progress report

    SciTech Connect

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

    1994-02-18

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

  17. Effect of long-term stress relief annealing on properties of low-alloy weld deposit of covered electrodes for welding of thick-walled nuclear constructions

    NASA Astrophysics Data System (ADS)

    Niagaj, Jerzy

    2012-09-01

    The article discusses the results of tests on the impact of long-term stress relief annealing at 620-650°C and cooling at a rate of 10°C/h on the mechanical properties of low-alloy weld deposits of covered electrodes containing 1.5-3% Ni, 0-0.3% Mo and 0.01-0.03% P. The article also contains information on the most advantageous nickel content for obtaining the highest impact energy (KV) values in subzero temperatures. X-ray structural analysis revealed that such weld deposits contain solely Fe3C carbides, which prevents the impact of molybdenum carbides on the change of KV. The study also confirmed the adverse effect of phosphorus on the weld deposit impact energy after long-lasting heat treatment.

  18. Nuclear analytical chemistry

    SciTech Connect

    Brune, D.; Forkman, B.; Persson, B.

    1984-01-01

    This book covers the general theories and techniques of nuclear chemical analysis, directed at applications in analytical chemistry, nuclear medicine, radiophysics, agriculture, environmental sciences, geological exploration, industrial process control, etc. The main principles of nuclear physics and nuclear detection on which the analysis is based are briefly outlined. An attempt is made to emphasise the fundamentals of activation analysis, detection and activation methods, as well as their applications. The book provides guidance in analytical chemistry, agriculture, environmental and biomedical sciences, etc. The contents include: the nuclear periodic system; nuclear decay; nuclear reactions; nuclear radiation sources; interaction of radiation with matter; principles of radiation detectors; nuclear electronics; statistical methods and spectral analysis; methods of radiation detection; neutron activation analysis; charged particle activation analysis; photon activation analysis; sample preparation and chemical separation; nuclear chemical analysis in biological and medical research; the use of nuclear chemical analysis in the field of criminology; nuclear chemical analysis in environmental sciences, geology and mineral exploration; and radiation protection.

  19. Nuclear war: Opposing viewpoints

    SciTech Connect

    Szumski, B.

    1985-01-01

    This book presents opposing viewpoints on nuclear war. Topics discussed include: how nuclear would begin; would humanity survive; would civil defense work; will an arms agreement work; and can space weapons reduce the risk of nuclear war.

  20. Nuclear Quadrupole Moments and Nuclear Shell Structure

    DOE R&D Accomplishments Database

    Townes, C. H.; Foley, H. M.; Low, W.

    1950-06-23

    Describes a simple model, based on nuclear shell considerations, which leads to the proper behavior of known nuclear quadrupole moments, although predictions of the magnitudes of some quadrupole moments are seriously in error.

  1. Nuclear thermal/nuclear electric hybrids

    NASA Technical Reports Server (NTRS)

    Reid, B. D.

    1991-01-01

    A description is given of the nuclear thermal and nuclear electric hybrid. The specifications are described along with its mission performance. Next, the technical status, development requirements, and some cost estimates are provided.

  2. Effects of electronic and nuclear interactions on the excited-state properties and structural dynamics of copper(I) diimine complexes.

    PubMed

    Mara, Michael W; Jackson, Nicholas E; Huang, Jier; Stickrath, Andrew B; Zhang, Xiaoyi; Gothard, Nosheen A; Ratner, Mark A; Chen, Lin X

    2013-02-14

    The effects of structural constraints on the metal-to-ligand charge transfer (MLCT) excited state structural dynamics of cuprous bis-2,9-diphenyl-phenanthroline ([Cu(I)(dpp)(2)](+)) in both coordinating acetonitrile and noncoordinating toluene were studied using X-ray transient absorption (XTA) spectroscopy and density functional theory (DFT) calculations. The phenyl groups attached to the phenanthroline ligands not only effectively shield the Cu(I) center from solvent molecules, but also force a flattened tetrahedral coordination geometry of the Cu(I) center. Consequently, the MLCT state lifetime in [Cu(I)(dpp)(2)](+) is solvent-independent, unlike the previously studied 2,9-methyl substituted bis-phenanthroline Cu(I) complex. The MLCT state of [Cu(I)(dpp)(2)](+) still undergoes a "pseudo Jahn-Teller distortion," with the angle between the two phenanthroline ligand planes decreased further by 7°. The XTA results indicate that, in the MLCT excited state of [Cu(I)(dpp)(2)](+), the phenyls at the 2, 9 positions of the phenanthroline rotate, breaking the π-π interaction with the phenanthroline ligands without ever rotating in-plane with the phenanthroline ligands. Hence, the transferred electron density from the Cu(I) center is localized on the phenanthroline moiety with no charge density present on the phenyl rings. The insight about the effect of the structural constraints on the MLCT state properties will guide the design of Cu(I) diimine complexes with suitable excited-state properties to function as earth-abundant dye sensitizers for solar electricity generation.

  3. Elements of a nuclear criticality safety program

    SciTech Connect

    Hopper, C.M.

    1995-07-01

    Nuclear criticality safety programs throughout the United States are quite successful, as compared with other safety disciplines, at protecting life and property, especially when regarded as a developing safety function with no historical perspective for the cause and effect of process nuclear criticality accidents before 1943. The programs evolved through self-imposed and regulatory-imposed incentives. They are the products of conscientious individuals, supportive corporations, obliged regulators, and intervenors (political, public, and private). The maturing of nuclear criticality safety programs throughout the United States has been spasmodic, with stability provided by the volunteer standards efforts within the American Nuclear Society. This presentation provides the status, relative to current needs, for nuclear criticality safety program elements that address organization of and assignments for nuclear criticality safety program responsibilities; personnel qualifications; and analytical capabilities for the technical definition of critical, subcritical, safety and operating limits, and program quality assurance.

  4. Structure of different grades of nuclear graphite

    NASA Astrophysics Data System (ADS)

    Mironov, B. E.; Westwood, A. V. K.; Scott, A. J.; Brydson, R.; Jones, A. N.

    2012-07-01

    Owing to its low neutron absorption cross-section, large scattering cross section and thermal and chemical stability, graphite is a key component of operational nuclear reactors where it is used as a moderator, reflector and as major structural component for 90% of current UK nuclear plants. It is also of interest for use in developing the future high temperature gas-cooled reactors. The properties of the nuclear graphite are influenced by its structural characteristics, which change as a function of neutron irradiation, temperature and oxidation. The principal structural changes during neutron irradiation that affect the integrity and dimensions of nuclear graphite components, thereby affecting service lifetime, are that the a-axis contracts and the c-axis expands in the crystallites. Characterization of virgin graphite structure and of the damage evolution after irradiation of nuclear graphite has an important role to play in the understanding and development of materials used in current and future nuclear reactors, respectively.

  5. Nuclear Fuel Cycle & Vulnerabilities

    SciTech Connect

    Boyer, Brian D.

    2012-06-18

    The objective of safeguards is the timely detection of diversion of significant quantities of nuclear material from peaceful nuclear activities to the manufacture of nuclear weapons or of other nuclear explosive devices or for purposes unknown, and deterrence of such diversion by the risk of early detection. The safeguards system should be designed to provide credible assurances that there has been no diversion of declared nuclear material and no undeclared nuclear material and activities.

  6. Nuclear South Asia

    DTIC Science & Technology

    2007-11-02

    inseparable from the history of nuclear developments in both India and Pakistan. The timing of India’s tests was determined by the pronuclear stance of the...Rawalpindi, 2001), 17-18. 53 3Robert Boardman, The Politics of Fading Dreams: Britain and the Nuclear Export Business, Nuclear Exports and World Politics (New...disasters of nuclear arms race. 61 BIBLIOGRAPHY Books Boardman, Robert. The Politics of Fading Dreams: Britain and the Nuclear Export Business, Nuclear

  7. Hollow nuclear matter

    NASA Astrophysics Data System (ADS)

    Yong, Gao-Chan

    2016-01-01

    It is generally considered that an atomic nucleus is always compact. Based on the isospin-dependent Boltzmann nuclear transport model, here I show that large block nuclear matter or excited nuclear matter may both be hollow. The size of the inner bubble in these matter is affected by the charge number of nuclear matter. The existence of hollow nuclear matter may have many implications in nuclear or atomic physics or astrophysics as well as some practical applications.

  8. Nuclear reactor

    DOEpatents

    Thomson, Wallace B.

    2004-03-16

    A nuclear reactor comprising a cylindrical pressure vessel, an elongated annular core centrally disposed within and spaced from the pressure vessel, and a plurality of ducts disposed longitudinally of the pressure vessel about the periphery thereof, said core comprising an annular active portion, an annular reflector just inside the active portion, and an annular reflector just outside the active a portion, said annular active portion comprising rectangular slab, porous fuel elements radially disposed around the inner reflector and extending the length of the active portion, wedge-shaped, porous moderator elements disposed adjacent one face of each fuel element and extending the length of the fuel element, the fuel and moderator elements being oriented so that the fuel elements face each other and the moderator elements do likewise, adjacent moderator elements being spaced to provide air inlet channels, and adjacent fuel elements being spaced to provide air outlet channels which communicate with the interior of the peripheral ducts, and means for introducing air into the air inlet channels which passes through the porous moderator elements and porous fuel elements to the outlet channel.

  9. Nuclear Proliferation: A Global Nuclear Strategy

    DTIC Science & Technology

    2007-03-30

    thinking about nuclear weapons as a “ Wild Card ” in this case. Finally, just as North Korea is using nuclear weapons as a “bargaining chip,” we...definite disadvantage for non-nuclear nations not to have a nuclear” Wild Card ”. So some misguided Japanese politicians are attracted to the “ Wild Card ” advantage

  10. Nuclear weapons modernizations

    NASA Astrophysics Data System (ADS)

    Kristensen, Hans M.

    2014-05-01

    This article reviews the nuclear weapons modernization programs underway in the world's nine nuclear weapons states. It concludes that despite significant reductions in overall weapons inventories since the end of the Cold War, the pace of reductions is slowing - four of the nuclear weapons states are even increasing their arsenals, and all the nuclear weapons states are busy modernizing their remaining arsenals in what appears to be a dynamic and counterproductive nuclear competition. The author questions whether perpetual modernization combined with no specific plan for the elimination of nuclear weapons is consistent with the nuclear Non-Proliferation Treaty and concludes that new limits on nuclear modernizations are needed.

  11. General Nuclear Medicine

    MedlinePlus

    ... Children's (Pediatric) Nuclear Medicine Radioactive Iodine (I-131) Therapy Biopsies - Overview Radioimmunotherapy (RIT) Alzheimer's Disease X-ray, Interventional Radiology and Nuclear Medicine ...

  12. Focused technology: Nuclear propulsion

    NASA Technical Reports Server (NTRS)

    Miller, Thomas J.

    1993-01-01

    Five viewgraphs are presented that outline the objectives and elements of the Nuclear Propulsion Program, mission considerations, propulsion technologies, and the logic flow path for nuclear propulsion development.

  13. Nuclear weapons modernizations

    SciTech Connect

    Kristensen, Hans M.

    2014-05-09

    This article reviews the nuclear weapons modernization programs underway in the world's nine nuclear weapons states. It concludes that despite significant reductions in overall weapons inventories since the end of the Cold War, the pace of reductions is slowing - four of the nuclear weapons states are even increasing their arsenals, and all the nuclear weapons states are busy modernizing their remaining arsenals in what appears to be a dynamic and counterproductive nuclear competition. The author questions whether perpetual modernization combined with no specific plan for the elimination of nuclear weapons is consistent with the nuclear Non-Proliferation Treaty and concludes that new limits on nuclear modernizations are needed.

  14. Nuclear magnetic resonance: Its role as a microscopic probe of the electronic and magnetic properties of High-Tc superconductors and related materials

    SciTech Connect

    Suh, Byoung Jin

    1995-12-27

    NMR experiments are reported for Sr2CuO2Cl2, HgBa2CuO4+d, YNi2B2C and YBa2Cu3O7. NMR studies typify three different aspects of microscopic properties of HTSC. In non-superconducting antiferromagnetic (AF) prototype Sr2CuO2Cl2, we used NMR to investigate Cu2+ correlated spin dynamics and AF phase transition in CuO2 layers. In the superconductors, we used NMR both to investigate the electronic properties of the Fermi-liquid in normal and superconducting states and to investigate flux lattice and flux-line dynamics in the superconducting state in presence of magnetic field. A summary of each study is given: 35Cl NMR was measured in Sr2CuO2Cl2 single crystals with TN=257K. 35Cl NMR relaxation rates showed crossover of Cu2+ spin dynamics from Heisenberg to XY-like correlation at 290 K well above TN. A field-dependent TN for H$\\perp$c was observed and explained by a field-induced Ising-like anisotropy in ab plane. 199Hg NMR was measured in HgBa2CuO4+d. Properties of the Fermi-liquid are characterized by a single-spin fluid picture and opening of a spin pseudo-gap at q=0 above Tc. Below Tc spin component of Knight shift decreases rapidly in agreement with prediction for d-wave pairing scheme. 11B and 89Y NMR/magnetization were measured in YNi2B2C. Temperature dependence of 11B Knight shift and of the NSLR gave a normal state which agrees with the Korringa relation, indicating that the AF fluctuations on the Ni sublattice are negligible. Opening of the superconducting gap obeys BCS. A NMR approach to investigate vortex thermal motion in HTSC is presented, based on contribution of thermal flux-lines motion

  15. Nudat: Nuclear Structure and Decay Data from the National Nuclear Data Center (NNDC)

    DOE Data Explorer

    NuDat allows users to search and plot nuclear structure and decay data interactively. NuDat was developed by the National Nuclear Data Center (NNDC)but utilizes contributions from physicists around the world. It provides an interface between web users and several databases containing nuclear structure, nuclear decay and some neutron-induced nuclear reaction information. Users can search for nuclear level properties (energy, half-life, spinparity), gamma-ray information (energy, intensity, multipolarity, coincidences), radiation information following nuclear decay (energy, intensity, dose), and neutron-induced reaction data from the BNL-325 book (thermal cross section and resonance integral). The information provided by NuDat 2 can be viewed in tables, level schemes and an interactive chart of nuclides.

  16. A promoter element with enhancer properties, and the orphan nuclear receptor RORalpha, are required for Purkinje cell-specific expression of a Gi/o modulator.

    PubMed

    Serinagaoglu, Yelda; Zhang, Rui; Zhang, Yufang; Zhang, Linda; Hartt, Greg; Young, Anthony P; Oberdick, John

    2007-03-01

    The promoter and structural portion of the gene, Pcp-2(L7), has frequently been used to target expression of proteins to cerebellar Purkinje cells. In our continuing analysis of the transcription of this gene and how it relates to the G-protein and Ca2+ channel modulatory functions of the encoded protein, we have dissociated the promoter and structural gene and identified cooperative functions. A 0.9 kb fragment of the proximal promoter has positional properties of a classical enhancer, yet its function requires the presence of the structural gene. We demonstrate that RORalpha, the gene product of the mutant mouse locus called staggerer (Rora(sg)), binds to and activates expression through this promoter element using functional assays in vitro and in vivo. The structural gene has a repressive effect on gene expression outside Purkinje cells, and likely participates in the suppression of Pcp-2(L7) gene expression in the many other brain and non-neuronal cell types, besides Purkinje cells, known to express RORalpha. Additional studies in vivo show that while Pcp-2(L7) expression is dependent on RORalpha throughout the cerebellum, this dependence is greatest in the intermediate region between the vermis and far lateral hemispheres. Thus, in addition to its recently indicated role in Ca2+-mediated reciprocal cell-cell signaling in Purkinje cells, RORalpha may also contribute to functional differences in cerebellar subregions.

  17. Metabolic profiling of strawberry grape ( Vitis × labruscana cv. 'Isabella') components by nuclear magnetic resonance (NMR) and evaluation of their antioxidant and antiproliferative properties.

    PubMed

    Pacifico, Severina; D'Abrosca, Brigida; Scognamiglio, Monica; Gallicchio, Marialuisa; Potenza, Nicoletta; Piccolella, Simona; Russo, Aniello; Monaco, Pietro; Fiorentino, Antonio

    2011-07-27

    In the assessment of the antioxidant properties of edible plants, the widely consumed Vitis × labruscana cv. 'Isabella', known in Italy as "fragola" (strawberry) grape, was of interest. Phenol and flavonoid contents of the methanolic extracts of peel, pulp, seed, leaf, and stalk components of the plant were determined. The metabolic profile of the extracts was performed by 1D and 2D NMR. Quantitative analysis, obtained in the presence of 0.01% of internal standard trimethylsilyl propionate, evidenced the presence of catechins in both stalk and seed extracts, whereas caffeic acid and quercetin were the main metabolites of the leaf extract. Furthermore, the extracts were tested for their radical scavenging and reducing capacities by measuring their capacity to scavenge DPPH(•) and ABTS(•+) and to reduce Fe(III) and Mo(VI) salts. The antioxidant efficacy of the extracts in cell-free systems and their antiproliferative activity toward HepG2 and A549 cells were also evaluated. Seed and stalk components are able to reduce by 39.6 and 40.6%, respectively, the amount of the metabolically active HepG2 cells after only 24 h of exposure.

  18. Nuclear astrophysics in the laboratory and in the universe

    SciTech Connect

    Champagne, A. E. Iliadis, C.; Longland, R.

    2014-04-15

    Nuclear processes drive stellar evolution and so nuclear physics, stellar models and observations together allow us to describe the inner workings of stars and their life stories. This Information on nuclear reaction rates and nuclear properties are critical ingredients in addressing most questions in astrophysics and often the nuclear database is incomplete or lacking the needed precision. Direct measurements of astrophysically-interesting reactions are necessary and the experimental focus is on improving both sensitivity and precision. In the following, we review recent results and approaches taken at the Laboratory for Experimental Nuclear Astrophysics (LENA, http://research.physics.unc.edu/project/nuclearastro/Welcome.html )

  19. Three-Dimensional Nuclear Chart--Understanding Nuclear Physics and Nucleosynthesis in Stars

    ERIC Educational Resources Information Center

    Koura, Hiroyuki

    2014-01-01

    Three-dimensional (3D) nuclear charts were created using toy blocks, which represent the atomic masses per nucleon number and the total half-lives for each nucleus in the entire region of the nuclear mass. The bulk properties of the nuclei can be easily understood by using these charts. Subsequently, these charts were used in outreach activities…

  20. Three-Dimensional Nuclear Chart--Understanding Nuclear Physics and Nucleosynthesis in Stars

    ERIC Educational Resources Information Center

    Koura, Hiroyuki

    2014-01-01

    Three-dimensional (3D) nuclear charts were created using toy blocks, which represent the atomic masses per nucleon number and the total half-lives for each nucleus in the entire region of the nuclear mass. The bulk properties of the nuclei can be easily understood by using these charts. Subsequently, these charts were used in outreach activities…

  1. Nuclear reactor

    DOEpatents

    Yant, Howard W.; Stinebiser, Karl W.; Anzur, Gregory C.

    1977-01-01

    A nuclear reactor, particularly a liquid-metal breeder reactor, whose upper internals include outlet modules for channeling the liquid-metal coolant from selected areas of the outlet of the core vertically to the outlet plenum. The modules are composed of a highly-refractory, high corrosion-resistant alloy, for example, INCONEL-718. Each module is disposed to confine and channel generally vertically the coolant emitted from a subplurality of core-component assemblies. Each module has a grid with openings, each opening disposed to receive the coolant from an assembly of the subplurality. The grid in addition serves as a holdown for the assemblies of the corresponding subplurality preventing their excessive ejection upwardly from the core. In the region directly over the core the outlet modules are of such peripheral form that they nest forming a continuum over the core-component assemblies whose outlet coolant they confine. Each subassembly includes a chimney which confines the coolant emitted by its corresponding subassemblies to generally vertical flow between the outlet of the core and the outlet plenum. Each subplurality of assemblies whose emitted coolant is confined by an outlet module includes assemblies which emit lower-temperature coolant, for example, a control-rod assembly, or fertile assemblies, and assemblies which emit coolant of substantially higher temperature, for example, fuel-rod assemblies. The coolants of different temperatures are mixed in the chimneys reducing the effect of stripping (hot-cold temperature fluctuations) on the remainder of the upper internals which are composed typically of AISI-304 or AISI-316 stainless steel.

  2. Nuclear reactor

    DOEpatents

    Pennell, William E.; Rowan, William J.

    1977-01-01

    A nuclear reactor in which the core components, including fuel-rod assemblies, control-rod assemblies, fertile rod-assemblies, and removable shielding assemblies, are supported by a plurality of separate inlet modular units. These units are referred to as inlet module units to distinguish them from the modules of the upper internals of the reactor. The modular units are supported, each removable independently of the others, in liners in the supporting structure for the lower internals of the reactor. The core assemblies are removably supported in integral receptacles or sockets of the modular units. The liners, units, sockets and assmblies have inlet openings for entry of the fluid. The modular units are each removably mounted in the liners with fluid seals interposed between the opening in the liner and inlet module into which the fluid enters and the upper and lower portion of the liner. Each assembly is similarly mounted in a corresponding receptacle with fluid seals interposed between the openings where the fluid enters and the lower portion of the receptacle or fitting closely in these regions. As fluid flows along each core assembly a pressure drop is produced along the fluid so that the fluid which emerges from each core assembly is at a lower pressure than the fluid which enters the core assembly. However because of the seals interposed in the mountings of the units and assemblies the pressures above and below the units and assemblies are balanced and the units are held in the liners and the assemblies are held in the receptacles by their weights as they have a higher specific gravity than the fluid. The low-pressure spaces between each module and its liner and between each core assembly and its module is vented to the low-pressure regions of the vessel to assure that fluid which leaks through the seals does not accumulate and destroy the hydraulic balance.

  3. Nuclear Fission Research at IRMM

    SciTech Connect

    Hambsch, Franz-Josef

    2005-05-24

    The Institute for Reference Materials and Measurements (IRMM) will celebrate its 45th anniversary in 2005. With its 150-MeV Geel Electron Linear Accelerator (GELINA) and 7-MV Van de Graaff accelerator as multi-purpose neutron sources, it served the nuclear physics community for this period.The research in the field of nuclear fission was focused in recent years on both the measurement and calculation of fission cross sections, and the measurement of fission fragment properties.Fission cross sections were determined for 233Pa and 234U; the fission process was studied in the resolved resonance region of 239Pu(n,f) and for 251Cf(nth,f). These measurements derive their interest from accelerator driven systems, the thorium fuel cycle, high temperature reactors, safety issues of current reactors, and basic physics. The measurements are supported by several modeling efforts that aim at improving model codes and nuclear data evaluation.

  4. Nuclear Power in China

    NASA Astrophysics Data System (ADS)

    Zhou, Yun

    2012-02-01

    In response to the Fukushima accident, China is strengthening its nuclear safety at reactors in operation, under construction and in preparation, including efforts to improve nuclear safety regulations and guidelines based on lessons learned from the accident. Although China is one of the major contributors in the global nuclear expansion, China's nuclear power industry is relatively young. Its nuclear safety regulators are less experienced compared to those in other major nuclear power countries. To realize China's resolute commitment to rapid growth of safe nuclear energy, detailed analyses of its nuclear safety regulatory system are required. This talk explains China's nuclear energy program and policy at first. It also explores China's governmental activities and future nuclear development after Fukushima accidents. At last, an overview of China's nuclear safety regulations and practices are provided. Issues and challenges are also identified for police makers, regulators, and industry professionals.

  5. Nuclear physics and astrophysics

    SciTech Connect

    Schramm, D.N.; Olinto, A.V.

    1992-09-01

    We have investigated a variety of research topics on the interface of nuclear physics and astrophysics during the past year. We have continued our study of dihyperon states in dense matter and have started to make a connection between their properties in the core of neutron stars with the ongoing experimental searches at Brookhaven National Laboratory. We started to build a scenario for the origin of gamma-ray bursts using the conversion of neutron stars to strange stars close to an active galactic nucleous. We have been reconsidering the constraints due to neutron star cooling rates on the equation of state for high density matter in the light, of recent findings which show that the faster direct Urca cooling process is possible for a range of nuclear compositions. We have developed a model for the formation of primordial magnetic fields due to the dynamics of the quark-hadron phase transition. Encouraged by the most recent observational developments, we have investigated the possible origin of the boron and beryllium abundances. We have greatly improved the calculations of the primordial abundances of these elements I>y augmenting the reaction networks and by updating the most recent experimental nuclear reaction rates. Our calculations have shown that the primordial abundances are much higher than previously thought but that the observed abundances cannot be explained by primordial sources alone. We have also studied the origin of the boron and beryllium abundances due to cosmic ray spallation. Finally, we have continued to address the solar neutrino problem by investigating the impact of astrophysical uncertainties on the MSW solution for a full three-family treatment of MSW mixing.

  6. Multiple vesiculoviral matrix proteins inhibit both nuclear export and import

    PubMed Central

    Petersen, Jeannine M.; Her, Lu-Shiun; Dahlberg, James E.

    2001-01-01

    The matrix (M) protein of vesicular stomatitis virus inhibits both nuclear import and export. Here, we demonstrate that this inhibitory property is conserved between the M proteins from two other vesiculoviruses, chandipura virus and spring viremia carp virus. All three M proteins completely block nuclear transport of spliced mRNA, small nuclear RNAs, and small nuclear ribonucleoproteins and slow the nuclear transport of many other cargoes. In all cases where transport was merely slowed by the M proteins, the chandipura virus M protein had the strongest inhibitory activity. When expressed in transfected HeLa cells, active M proteins displayed prominent association with the nuclear rim. Moreover, mutation of a conserved methionine abolished both the inhibitory activity and efficient targeting of the M proteins to the nuclear rim. We propose that all of the vesiculoviral M proteins associate with the same nuclear target, which is likely to be a component of the nuclear pore complex. PMID:11447272

  7. Nuclear and magnetic structures and magnetic properties of the layered cobalt hydroxysulfate Co5(OH)6(SO4)2(H2O)4 and its deuterated analogue, Co5(OD)6(SO4)2(D2O)4.

    PubMed

    Salah, Mohsen Ben; Vilminot, Serge; André, Gilles; Richard-Plouet, Mireille; Mhiri, Tahar; Takagi, Seishi; Kurmoo, Mohamedally

    2006-06-21

    The structures (nuclear and magnetic), magnetic properties (2-300 K, 1-10(4) bar), and heat capacity of the layered ferromagnet Co5(OH)6(SO4)2(H2O)4 are reported. The crystal structure consists of brucite-like M(II)-OH layers of edge-sharing octahedra, but having two different Co sites, which are pillared by ...O3SO-Co(H2O)4-OSO3.... The absorption spectrum confirms the presence of divalent Co, and by comparison of the two isotopic materials, the assignment of the vibrational spectra is proposed. The magnetic properties are those of a ferromagnet with a Curie temperature of 14 K. Temperature and field dependence magnetization data taken on an aligned sample suggest an easy-plane magnet. The Curie temperature increases linearly with pressure at a rate of +0.12 K/kbar, suggesting small progressive and uniform modifications of the Co-Co exchange interactions. Rietveld refinement of the neutron powder diffraction data and consideration of a group analysis reveal the direction of the moments of the Co within the layer to be along the b-axis, with a maximum moment of 3.33 micro(B) per cobalt. Those of the pillars remain random. Estimation of the entropy from the heat capacity data accounts for the presence of four ordered moments of Co with spin 1/2 at the long-range ordering temperature, while the moment of the pillaring Co contributes only at lower temperature due to the increase of the internal field as the temperature is lowered. The purely 2D-magnetic ordering in an easy-plane magnet, evidenced by neutron diffraction and heat capacity, challenges the existing theories and is a rare example of a single-layer magnet.

  8. Exotic States of Nuclear Matter

    NASA Astrophysics Data System (ADS)

    Lombardo, Umberto; Baldo, Marcello; Burgio, Fiorella; Schulze, Hans-Josef

    2008-02-01

    pt. A. Theory of nuclear matter EOS and symmetry energy. Constraining the nuclear equation of state from astrophysics and heavy ion reactions / C. Fuchs. In-medium hadronic interactions and the nuclear equation of state / F. Sammarruca. EOS and single-particle properties of isospin-asymmetric nuclear matter within the Brueckner theory / W. Zuo, U. Lombardo & H.-J. Schulze. Thermodynamics of correlated nuclear matter / A. Polls ... [et al.]. The validity of the LOCV formalism and neutron star properties / H. R. Moshfegh ... [et al.]. Ferromagnetic instabilities of neutron matter: microscopic versus phenomenological approaches / I. Vidaã. Sigma meson and nuclear matter saturation / A. B. Santra & U. Lombardo. Ramifications of the nuclear symmetry energy for neutron stars, nuclei and heavy-ion collisions / A. W. Steiner, B.-A. Li & M. Prakash. The symmetry energy in nuclei and nuclear matter / A. E. L. Dieperink. Probing the symmetry energy at supra-saturation densities / M. Di Toro et al. Investigation of low-density symmetry energy via nucleon and fragment observables / H. H. Wolter et al. Instability against cluster formation in nuclear and compact-star matter / C. Ducoin ... [et al.]. Microscopic optical potentials of nucleon-nucleus and nucleus-nucleus scattering / Z.-Y. Ma, J. Rong & Y.-Q. Ma -- pt. B. The neutron star crust: structure, formation and dynamics. Neutron star crust beyond the Wigner-Seitz approximation / N. Chamel. The inner crust of a neutron star within the Wigner-Seitz method with pairing: from drip point to the bottom / E. E. Saperstein, M. Baldo & S. V. Tolokonnikov. Nuclear superfluidity and thermal properties of neutron stars / N. Sandulescu. Collective excitations: from exotic nuclei to the crust of neutron stars / E. Khan, M. Grasso & J. Margueron. Monte Carlo simulation of the nuclear medium: fermi gases, nuclei and the role of Pauli potentials / M. A. Pérez-García. Low-density instabilities in relativistic hadronic models / C. Provid

  9. Terrorists and Nuclear Technology

    ERIC Educational Resources Information Center

    Krieger, David

    1975-01-01

    This essay explores the ways terrorist groups may gain possession of nuclear materials; the way in which they may use nuclear weapons and other nuclear technologies to their benefit; and various courses of action designed to minimize the possibilities of terrorists utilizing nuclear technology to their benefit and society's detriment. (BT)

  10. Terrorists and Nuclear Technology

    ERIC Educational Resources Information Center

    Krieger, David

    1975-01-01

    This essay explores the ways terrorist groups may gain possession of nuclear materials; the way in which they may use nuclear weapons and other nuclear technologies to their benefit; and various courses of action designed to minimize the possibilities of terrorists utilizing nuclear technology to their benefit and society's detriment. (BT)

  11. Nuclear medicine annual, 1984

    SciTech Connect

    Freeman, L.M.; Weissmann, H.S.

    1984-01-01

    The following topics are reviewed in this work: nuclear physicians role in planning for and handling radiation accidents; the role of nuclear medicine in evaluating the hypertensive patient; studies of the heart with radionuclides; role of radionuclide imaging in the patient undergoing chemotherapy; hematologic nuclear medicine; the role of nuclear medicine in sports related injuries; radionuclide evaluation of hepatic function with emphasis on cholestatis.

  12. Frontiers of Nuclear Structure

    SciTech Connect

    Nazarewicz, Witold

    1997-12-31

    Current developments in nuclear structure at the `limits` are discussed. The studies of nuclear behavior at extreme conditions provide us with invaluable information about the nature of the nuclear interaction and nucleonic correlations at various energy-distance scales. In this talk frontiers of nuclear structure are briefly reviewed from a theoretical perspective, mainly concentrating on medium-mass and heavy nuclei.

  13. The New Nuclear Nations.

    ERIC Educational Resources Information Center

    Spector, Leonard S.

    1990-01-01

    Explores the issue of nuclear proliferation, noting that the countries with nuclear capability now include Israel, South Africa, India, and Pakistan. Describes the role and problems of the United States in halting nuclearization. Supplies charts, maps, and information concerning the state of nuclear capability in each country. (NL)

  14. Nuclear energy and security

    SciTech Connect

    BLEJWAS,THOMAS E.; SANDERS,THOMAS L.; EAGAN,ROBERT J.; BAKER,ARNOLD B.

    2000-01-01

    Nuclear power is an important and, the authors believe, essential component of a secure nuclear future. Although nuclear fuel cycles create materials that have some potential for use in nuclear weapons, with appropriate fuel cycles, nuclear power could reduce rather than increase real proliferation risk worldwide. Future fuel cycles could be designed to avoid plutonium production, generate minimal amounts of plutonium in proliferation-resistant amounts or configurations, and/or transparently and efficiently consume plutonium already created. Furthermore, a strong and viable US nuclear infrastructure, of which nuclear power is a large element, is essential if the US is to maintain a leadership or even participatory role in defining the global nuclear infrastructure and controlling the proliferation of nuclear weapons. By focusing on new fuel cycles and new reactor technologies, it is possible to advantageously burn and reduce nuclear materials that could be used for nuclear weapons rather than increase and/or dispose of these materials. Thus, the authors suggest that planners for a secure nuclear future use technology to design an ideal future. In this future, nuclear power creates large amounts of virtually atmospherically clean energy while significantly lowering the threat of proliferation through the thoughtful use, physical security, and agreed-upon transparency of nuclear materials. The authors must develop options for policy makers that bring them as close as practical to this ideal. Just as Atoms for Peace became the ideal for the first nuclear century, they see a potential nuclear future that contributes significantly to power for peace and prosperity.

  15. Nuclear air cushion vehicles

    NASA Technical Reports Server (NTRS)

    Anderson, J. L.

    1973-01-01

    The state-of-the-art of the still-conceptual nuclear air cushion vehicle, particularly the nuclear powerplant is identified. Using mission studies and cost estimates, some of the advantages of nuclear power for large air cushion vehicles are described. The technology studies on mobile nuclear powerplants and conceptual ACV systems/missions studies are summarized.

  16. Detection for Nuclear Nonproliferation

    DOE PAGES

    Pozzi, Sara A.; Hamel, Michael C.; Polack, J. Kyle; ...

    2016-11-13

    The detection and characterization of special nuclear materials is a high priority area for applications in nuclear safeguards and nonproliferation. We are developing new instruments based on organic scintillators to detect and characterize the emissions from special nuclear materials. This paper describes some of the gaps and challenges in nuclear safeguards and proposed approaches.

  17. The New Nuclear Nations.

    ERIC Educational Resources Information Center

    Spector, Leonard S.

    1990-01-01

    Explores the issue of nuclear proliferation, noting that the countries with nuclear capability now include Israel, South Africa, India, and Pakistan. Describes the role and problems of the United States in halting nuclearization. Supplies charts, maps, and information concerning the state of nuclear capability in each country. (NL)

  18. Properties of nonaqueous electrolytes

    NASA Technical Reports Server (NTRS)

    Foster, J. N.; Hanson, D. C.; Hon, J. F.; Keller, R.; Muirhead, J. S.

    1970-01-01

    Physical property measurements and structural studies conducted in aprotic solvents using various solutes are applicable to the further development of lithum batteries. Structural studies utilize nuclear magnetic resonance and electron paramagnetic resonance techniques.

  19. Introductory Nuclear Physics, 2nd Edition

    NASA Astrophysics Data System (ADS)

    Wong, Samuel S. M.

    1998-08-01

    A comprehensive, unified treatment of present-day nuclear physics-the fresh edition of a classic text/reference. "A fine and thoroughly up-to-date textbook on nuclear physics . . . most welcome." -Physics Today (on the First Edition). What sets Introductory Nuclear Physics apart from other books on the subject is its presentation of nuclear physics as an integral part of modern physics. Placing the discipline within a broad historical and scientific context, it makes important connections to other fields such as elementary particle physics and astrophysics. Now fully revised and updated, this Second Edition explores the changing directions in nuclear physics, emphasizing new developments and current research-from superdeformation to quark-gluon plasma. Author Samuel S.M. Wong preserves those areas that established the First Edition as a standard text in university physics departments, focusing on what is exciting about the discipline and providing a concise, thorough, and accessible treatment of the fundamental aspects of nuclear properties. In this new edition, Professor Wong: * Includes a chapter on heavy-ion reactions-from high-spin states to quark-gluon plasma * Adds a new chapter on nuclear astrophysics * Relates observed nuclear properties to the underlying nuclear interaction and the symmetry principles governing subatomic particles * Regroups material and appendices to make the text easier to use * Lists Internet links to essential databases and research projects * Features end-of-chapter exercises using real-world data. Introductory Nuclear Physics, Second Edition is an ideal text for courses in nuclear physics at the senior undergraduate or first-year graduate level. It is also an important resource for scientists and engineers working with nuclei, for astrophysicists and particle physicists, and for anyone wishing to learn more about trends in the field.

  20. [Chilean nuclear policy].

    PubMed

    Bobadilla, E

    1996-06-01

    This official document is statement of the President of the Chilean Nuclear Energy Commission, Dr. Eduardo Bobadilla, about the nuclear policy of the Chilean State, Thanks to the international policy adopted by presidents Aylwin (1990-1994) and his successor Frei Ruiz Tagle (1994-), a nuclear development plan, protected by the Chilean entrance to the nuclear weapons non proliferation treaty and Tlatelolco Denuclearization treaty, has started. Chile will be able to develop without interference, an autonomous nuclear electrical system and other pacific uses of nuclear energy. Chile also supports a new international treaty to ban nuclear weapon tests.