Measurements of Cyclotron Features and Pulse Periods in the High-Mass X-Ray Binaries 4U 1538-522 and 4U 1907+09 with the International Gamma-Ray Astrophysics Laboratory

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Hemphill, Paul B.; Rothschild, Richard E.; Caballero, Isabel; Pottschmidt, Katja; Kuhnel, Matthias; Furst, Felix; Wilms, Jorn

2013-01-01

We present a spectral and timing analysis of International Gamma-Ray Astrophysics Laboratory (INTEGRAL) observations of two high-mass X-ray binaries, 4U 1538-522 and 4U 1907+09. Our timing measurements for 4U 1538-522 find the pulse period to have exhibited a spin-up trend until approximately 2009, after which there is evidence for a torque reversal, with the source beginning to spin down to the most recently measured period of 525.407 plus or minus 0.001 seconds. The most recent INTEGRAL observations of 4U 1907+09 are not found to yield statistically significant pulse periods due to the significantly lower flux from the source compared with 4U 1538-522. A spectral model consisting of a power-law continuum with an exponential cutoff and modified by two cyclotron resonance scattering features is found to fit both sources well, with the cyclotron scattering features detected at approximately 22 and approximately 49 kiloelectronvolts for 4U 1538-522 and at approximately 18 and approximately 36 kiloelectronvolts for 4U 1907+09. The spectral parameters of 4U 1538-522 are generally not found to vary significantly with flux and there is little to no variation across the torque reversal. Examining our results in conjunction with previous work, we find no evidence for a correlation between cyclotron line energy and luminosity for 4U 1538-522. 4U 1907+09 shows evidence for a positive correlation between cyclotron line energy and luminosity, which would make it the fourth, and lowest luminosity, cyclotron line source to exhibit this relationship.

4U 1907+09: an HMXB running away from the Galactic plane

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Gvaramadze, V. V.; Röser, S.; Scholz, R.-D.; Schilbach, E.

2011-05-01

We report the discovery of a bow shock around the high-mass X-ray binary (HMXB) 4U 1907+09 using the Spitzer Space Telescope 24 μm data (after Vela X-1 the second example of bow shocks associated with HMXBs). The detection of the bow shock implies that 4U 1907+09 is moving through space with a high (supersonic) peculiar velocity. To confirm the runaway nature of 4U 1907+09, we measured its proper motion, which for an adopted distance to the system of 4 kpc corresponds to a peculiar transverse velocity of ≃ 160 ± 115 km s-1, meaning that 4U 1907+09 is indeed a runaway system. This also supports the general belief that most HMXBs possess high space velocities. The direction of motion of 4U 1907+09 inferred from the proper motion measurement is consistent with the orientation of the symmetry axis of the bow shock, and shows that the HMXB is running away from the Galactic plane. We also present the Spitzer images of the bow shock around Vela X-1 (a system similar to 4U 1907+09) and compare it with the bow shock generated by 4U 1907+09.

Evolution of tidal capture X-ray binaries - 4U 2127+12 (M15) to 4U 1820-30 (NGC 6624)

International Nuclear Information System (INIS)

Bailyn, C.D.; Grindlay, J.E.

1987-01-01

A new evolutionary scenario for X-ray binaries in globular clusters, which begins with a tidal capture of a main-sequence star by a neutron star and ends with a white dwarf-neutron star system, is presented. For tidal captures of main-sequence stars into orbits too wide to begin mass transfer immediately, the subsequent evolution of the secondary can lead to a common envelope binary similar to what the 9 hr X-ray binary 4U 2127+12 in M15 is suspected to be. If the common envelope is thick enough, it may cause the neutron star and the white dwarf core of the secondary to spiral in, producing a detached white dwarf-neutron star system. Subsequently, gravitational radiation losses may evolve this into the configuration seen in the 11 minute X-ray binary 4U 1820-30 in NGC 6624. This model appears more likely on statistical grounds than formation by collision of a neutron star and a red giant. In some circumstances, the latter process may result in unstable mass transfer, which would result in coalescence rather than a binary system like 4U 1820-30. 34 references

Supporting Table A4 MULLICAN CHARGES (a.u.) and ...

Indian Academy of Sciences (India)

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1.135621. 64 H. 0.01933. -1.132721. 65 H. -0.259245. -1.126795. Supporting Table A5. MULLICAN CHARGES (a.u.) and ELECTROSTATIC POTENTIAL(a.u.). OF ATOMS OF 1CH4@512-METHANOL. ATOM ID. ATOM TYPE MULLIKAN CHARGES.

Comparative study of α and β-ThBr4: structure and luminescence. Spectroscopy of U4+ in α-ThBr4

International Nuclear Information System (INIS)

Simoni, E.

1988-05-01

UV absorption of β-ThBr 4 : presents a plain absorption front and for the same temperature the threshold energy has the same value than the threshold energy of excitation function and photocurrent peak. Emission intensity and lifetime decrease when temperature increases from 300 K to 400K (extinction temperature). Results are interpreted either by molecular orbital levels of the ThBr 8 4- cluster or either by conduction and valence bands of the matrix above. Absorption and emission spectra of U 4+ in α-ThBr 4 (where U 4+ has a S 4 symmetry) between 300 K and 4.2 K allow indexation of 30 levels. Spectroscopic parameters are calculated in D 2d and S 4 symmetry. Comparison of these parameters with those of U 4+ in β-ThBr 4 and β-ThCl 4 shows that crystal field force is practically the same in the three matrices but the structure transformation from β to α has more influence on B q k than ligand change from Br - to Cl - . Owing to very low phonon energy, fluorescence spectra of U 4+ is easy to observe in α-ThBr 4 as it is in β-ThBr 4 and ThCl 4 [fr

9 CFR 102.4 - U.S. Veterinary Biologics Establishment License.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false U.S. Veterinary Biologics... LICENSES FOR BIOLOGICAL PRODUCTS § 102.4 U.S. Veterinary Biologics Establishment License. (a) Before a U.S. Veterinary Biologics Establishment License will be issued by the Administrator for any establishment, an...

Synthesis, crystal structure and optical properties of the catena-metaphosphates Ce(PO3)4 and U(PO3)4

International Nuclear Information System (INIS)

Hoeppe, Henning A.; Daub, Michi

2012-01-01

The catena-metaphosphates of tetravalent cerium and tetravalent uranium were obtained as phase pure crystalline powders by reaction of the respective dioxides with phosphoric acid at 500 C. Ce(PO 3 ) 4 and U(PO 3 ) 4 crystallise in space group C2/c (Z = 16, a Ce = 13.7696(3) Aa, b Ce = 29.7120(7) Aa, c Ce = 8.9269(2) Aa, β Ce = 90.00(1) Aa 3 and a U = 13.786(3) Aa, b U = 29.843(6) Aa, c U = 8.9720(18) Aa, β U = 90.01(3) Aa 3 ). The vibrational and optical spectra of pale yellow Ce(PO 3 ) 4 and emerald-greenish U(PO 3 ) 4 are also reported. (orig.)

Redox equilibrium of U4+/U3+ in molten NaCl-2CsCl by UV-Vis spectrophotometry and cyclic voltammetry

International Nuclear Information System (INIS)

Nagai, Takayuki; Uehara, Akihiro; Fujii, Toshiyuki; Shirai, Osamu; Yamana, Hajimu; Sato, Nobuaki

2005-01-01

In order to investigate the redox equilibrium of uranium ions in molten NaCl-2CsCl, UV-Vis absorption spectro-photometry measurements were performed for U 4+ and U 3+ in molten NaCl-2CsCl at 923 K under simultaneous electrolytic control of their ratio. Prominent absorption bands at 480 and 570 nm were assigned to U 3+ , and their molar absorptivities were determined to be 1,260±42 and 963±32 mol -1 ·l·cm -1 respectively. From the dependence of the rest potential of the melt on the spectrophotometrically determined ratio of [U 4+ ]/[U 3+ ], the standard redox potential of the couple U 4+ /U 3+ at 923 K was determined to be -1.481±0.004 V vs. Cl 2 /Cl - . Cyclic voltammetry measurements were carried out for the couple U 4+ /U 3+ , and the results agreed well with this standard redox potential value. By the results of cyclic voltammetry, a temperature dependence of the standard redox potential was found to be -2.094+6.639 x 10 -4 T (T=823-923K). (author)

4U 1909+07: a Hidden Pearl

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I. Kreykenbohm

2011-01-01

Full Text Available We present a detailed spectral and timing analysis of the High Mass X-ray Binary (HMXB 4U 1909+07 with INTEGRAL and RXTE. 4U1909+07 is a persistent accreting X-ray pulsar with a period of approximately 605 s. The period changes erratically consistent with a random walk expected for a wind accreting system. INTEGRAL detects the source with an average of 2.4 cps (corresponding to 15mCrab, but sometimes exhibits flaring activity up to 50 cps (i.e. 300mCrab. The strongly energy dependent pulse profile shows a double peaked structure at low energies and only a single narrow peak at energies above 20 keV. The phase averaged spectrum is well described by a powerlaw modified at higher energies by an exponential cutoff and photoelectric absorption at low energies. In addition at 6.4 keV a strong iron fluorescence line and at lower energies a blackbody component are present. We performed phase resolved spectroscopy to study the pulse phase dependence of the spectral parameters: while most spectral parameters are constant within uncertainties, the blackbody normalization and the cutoff folding energy vary strongly with phase.

Emergence of a new S U (4 ) symmetry in the baryon spectrum

Science.gov (United States)

Denissenya, M.; Glozman, L. Ya.; Pak, M.

2015-10-01

Recently, a large degeneracy of J =1 mesons—that is, larger than the S U (2 )L×S U (2 )R×U (1 )A symmetry of the QCD Lagrangian—has been discovered upon truncation of the near-zero modes from the valence quark propagators. It has been found that this degeneracy represents the S U (4 ) group that includes the chiral rotations as well as the mixing of left- and right-handed quarks. This symmetry group turns out to be a symmetry of confinement in QCD. Consequently, one expects that the same symmetry should persist upon the near-zero mode removal in other hadron sectors as well. It has been shown that indeed the J =2 mesons follow the same symmetry pattern upon the low-lying mode elimination. Here we demonstrate the S U (4 ) symmetry of baryons once the near-zero modes are removed from the quark propagators. We also show a degeneracy of states belonging to different irreducible representations of S U (4 ). This implies a larger symmetry that includes S U (4 ) as a subgroup.

Electron loss from 1.4 MEV/u U4,6,10+ ions colliding with Ne, N2 and Ar targets

International Nuclear Information System (INIS)

DuBois, R.D.; Santos, A.C.F.; Stoehlker, T.

2004-07-01

Absolute, total, single, and multiple electron loss cross sections are measured for 1.4 MeV/u U 4,6,10+ ions colliding with neon and argon atoms and nitrogen molecules. It is found that the cross sections all have the same dependence on the number of electrons lost and that multiplying the cross sections by the initial number of electrons in the 6s, 6p, and 5f shells yields good agreement between the different projectiles. By combining the present data with previous measurements made at the same velocity, it is shown that the scaled cross sections slowly decrease in magnitude for incoming charge states between 1 and 10 whereas the cross sections for higher charge state ions fall off much more rapidly. (orig.)

BURST AND OUTBURST CHARACTERISTICS OF MAGNETAR 4U 0142+61

Energy Technology Data Exchange (ETDEWEB)

Göğüş, Ersin; Chakraborty, Manoneeta; Kaneko, Yuki [Sabancı University, Orhanlı-Tuzla, İstanbul 34956 (Turkey); Lin, Lin [Department of Astronomy, Beijing Normal University, Beijing 100875 (China); Roberts, Oliver J. [School of Physics, University College Dublin, Stillorgan Road, Belfield, Dublin 4 (Ireland); Gill, Ramandeep; Granot, Jonathan [Department of Natural Sciences, The Open University of Israel, 1 University Road, P.O. Box 808, Ranana 43537 (Israel); Horst, Alexander J. van der; Kouveliotou, Chryssa; Younes, George [Department of Physics, The George Washington University, Washington, DC 20052 (United States); Watts, Anna L. [Anton Pannekoek Institute for Astronomy, University of Amsterdam, Postbus 94249, NL-1090 GE Amsterdam (Netherlands); Baring, Matthew [Department of Physics and Astronomy, Rice University, MS-108, P.O. Box 1892, Houston, TX 77251 (United States); Huppenkothen, Daniela [Center for Data Science, New York University, 726 Broadway, 7th Floor, NY 10003 (United States)

2017-01-20

We have compiled the most comprehensive burst sample from magnetar 4U 0142+61, comprising 27 bursts from its three burst-active episodes in 2011, 2012 and the latest one in 2015 observed with Swift /Burst Alert Telescope and Fermi /Gamma-ray Burst Monitor. Bursts from 4U 0142+61 morphologically resemble typical short bursts from other magnetars. However, 4U 0142+61 bursts are less energetic compared to the bulk of magnetar bursts. We uncovered an extended tail emission following a burst on 2015 February 28, with a thermal nature, cooling over a timescale of several minutes. During this tail emission, we also uncovered pulse peak phase aligned X-ray bursts, which could originate from the same underlying mechanism as that of the extended burst tail, or an associated and spatially coincident but different mechanism.

Neutronic Analysis of the RSG-GAS Compact Core without CIP Silicide 3.55 g U/cc and 4.8 g U/cc

International Nuclear Information System (INIS)

Jati S; Lily S; Tukiran S

2004-01-01

Fuel conversion from U 3 O 8 -Al to U 3 Si 2 -Al 2.96 g U/cc density in the RSG-GAS core had done successfully step by step since 36 th core until 44 th core. So that, since the 45 th core until now (48 th core) had been using full of silicide 2.96 g U/cc. Even though utilization program of silicide fuel with high density (3.55 g U/cc and 4.8 g U/cc) and optimize operation of RSG-GAS core under research. Optimalitation of core with increasing operation cycle have been analyzing about compact core. The mean of compact core is the RSG-GAS core with decrease number of IP or CIP position irradiation. In this research, the neutronic calculation to cover RSG-GAS core and RSG-GAS core without CIP that are using U 3 Si 2 -Al 2.96 g U/cc, 3.55 g U/cc and 4.8 g U/cc had done. Two core calculation done at 15 MW power using SRAC-ASMBURN code. The calculation result show that fuel conversion from 2.96 g U/cc density to 3.55 g U/cc and 4.8 g U/cc will increasing cycle length for both RSG-GAS core and RSG-GAS compact core without CIP. However, increasing of excess reactivity exceeded from nominal value of first design that 9.2%. Change of power peaking factor is not show significant value and still less than 1.4. Core fuelled with U 3 Si 2 -Al 4.8 g U/cc density have maximum discharge burn-up which exceeded from licensing value (70%). RSG-GAS compact core without CIP fuelled U 3 Si 2 -Al 2.96 g U/cc have longer cycle operation then RSG-GAS core and fulfil limitation neutronic parameter at the first design value. (author)

Implementation of PWR steady state self-initialization feature into RELAP4/MOD6/U4/J3

International Nuclear Information System (INIS)

Yoshida, Kazuo

1987-07-01

A PWR steady state self-initialization feature has been implemented into the RELAP4/MOD6/U4/J3 code which is an improved version of RELAP4/MOD6 and can analyze not only large break but also small break LOCA in LWRs. This feature is originated from RELAP4/MOD7 which is the most updated released version of RELAP4 from INEL. Several FORTRAN subroutines in MOD7 related to this feature were transplanted into MOD6/U4/J3 with some improvements, which were the modification of method to take a balance of heat transfer between primary and secondary side at SG-U tubes, and to make it possible to nodalize secondary side of SG as multi-node. Advantages realized by implementation of this option are saving of time in initializaing a new model and an assurance of steady state and self consistency of input data in a small break LOCA analysis of a PWR. (author)

Search for UHE emission from 4U0115+63

International Nuclear Information System (INIS)

Alexandreas, D.E.; Allen, R.C.; Biller, S.D.; Dion, G.M.; Lu, X-Q.; Vishwanath, P.R.; Yodh, G.B.; Berley, D.; Chang, C.Y.; Dingus, B.L.; Dion, C.; Goodman, J.A.; Gupta, S.K.; Haines, T.J.; Kwok, P.W.; Stark, M.J.; Burman, R.L.; Hoffman, C.M.; Lloyd-Evans, J.; Nagle, D.E.; Potter, M.E.; Sandberg, V.D.; Zhang, W.P.; Cady, D.R.; Ellsworth, R.W.; Krakauer, D.A.; Talaga, R.L.

1990-01-01

We report here the preliminary results of our observations of the sporadic x-ray binary system 4U0115 + 63. The CYGNUS air shower array has been collecting data since April 1986. No significant excess is seen from the direction of this source, nor any correlation with its 24-day orbital period. A 90% confidence-level upper limit on the flux from 4U0115 + 63 is 2.8 x 10 -13 cm -2 s -1 above 50 TeV. This flux limit is considerably lower than those reported by other UHE experiments. Search for periodicity at the neutron star frequency is in progress. 12 refs., 3 figs., 1 tab

LILRB4 Decrease on uDCs Exacerbate Abnormal Pregnancy Outcomes Following Toxoplasma gondii Infection

Directory of Open Access Journals (Sweden)

Shaowei Zhan

2018-03-01

Full Text Available Toxoplasma gondii (T. gondii infection in early pregnancy can result in miscarriage, dead fetus, and other abnormalities. The LILRB4 is a central inhibitory receptor in uterine dendritic cells (uDCs that plays essential immune-regulatory roles at the maternal–fetal interface. In this study, T. gondii-infected human primary uDCs and T. gondii-infected LILRB4-/- pregnant mice were utilized. The immune mechanisms underlying the role of LILRB4 on uDCs were explored in the development of abnormal pregnancy outcomes following T. gondii infection in vitro and in vivo. Our results showed that the expression levels of LILRB4 on uDCs from normal pregnant mice were obviously higher than non-pregnant mice, and peaked in mid-gestation. The LILRB4 expression on uDC subsets, especially tolerogenic subsets, from mid-gestation was obviously down-regulated after T. gondii infection and LILRB4 decrease could further regulate the expression of functional molecules (CD80, CD86, and HLA-DR or MHC II on uDCs, contributing to abnormal pregnancy outcomes. Our results will shed light on the molecular immune mechanisms of uDCs in abnormal pregnancy outcomes by T. gondii infection.

48 CFR 15.403-4 - Requiring certified cost or pricing data (10 U.S.C. 2306a and 41 U.S.C. 254b).

Science.gov (United States)

2010-10-01

... or pricing data (10 U.S.C. 2306a and 41 U.S.C. 254b). 15.403-4 Section 15.403-4 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Contract Pricing 15.403-4 Requiring certified cost or pricing data (10 U.S.C. 2306a and 41 U.S.C...

Industrija 4.0 - sadašnjost ili budućnost u Hrvatskoj

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Matejak, Nedeljko

2017-01-01

Tehnološki razvoj generator je dinamičnih promjena gotovo u svim područjima koje dotiče. Jedno od područja koje prolazi kroz intenzivnu tranziciju je industrijska proizvodnja. U prilog tome govori transformacija iz treće industrijske revolucije u četvrtu, dok zapravo dio globalne ekonomije nije napravio potpunu transformaciju u treću industrijsku revoluciju. Pojam Industrija 4.0 opisuje što se nalazi na putu transformacije postojeće industrijske proizvodnje u novu, primarn...

On hyperbolic U4 manifolds with local duality

International Nuclear Information System (INIS)

Wallner, R.P.

1982-01-01

We use the decomposition of the Riemann/Cartan curvature 2-forms Ωsup(ij) in terms of their irreducible parts under the Lorentz group to examine the irreducible content of self- and anti-self double dual curvature forms Ωsup(+-ij) and their further refinements involving left and right duals. In the case of local duality (i.e. Ωsup(ij) = Ωsup(+-ij) locally), some consequences to curvature and torsion are easily derived in this way. As Riemann/Cartan space-times (U 4 -space-times) are subject to generalized gravity theories, some (vacuum) field equations proposed there are also taken into considerations. As an application to the various decompositions of curvature and torsion we point out their utility in the search of exact solutions of U 4 -field equations. To simplify notations and calculations, the calculus of exterior forms is used throughout. (Author)

Theoretical modeling of the uranium 4f XPS for U(VI) and U(IV) oxides

Energy Technology Data Exchange (ETDEWEB)

Bagus, Paul S. [Department of Chemistry, University of North Texas, Denton, Texas 76203-5017 (United States); Nelin, Connie J. [Consulting and Services, 6008 Maury' s Trail, Austin, Texas 78730 (United States); Ilton, Eugene S. [Pacific Northwest National Laboratory, Richland, Washington 99352 (United States)

2013-12-28

A rigorous study is presented of the physical processes related to X-Ray photoelectron spectroscopy, XPS, in the 4f level of U oxides, which, as well as being of physical interest in themselves, are representative of XPS in heavy metal oxides. In particular, we present compelling evidence for a new view of the screening of core-holes that extends prior understandings. Our analysis of the screening focuses on the covalent mixing of high lying U and O orbitals as opposed to the, more common, use of orbitals that are nominally pure U or pure O. It is shown that this covalent mixing is quite different for the initial and final, core-hole, configurations and that this difference is directly related to the XPS satellite intensity. Furthermore, we show that the high-lying U d orbitals as well as the U(5f) orbital may both contribute to the core-hole screening, in contrast with previous work that has only considered screening through the U(5f) shell. The role of modifying the U-O interaction by changing the U-O distance has been investigated and an unexpected correlation between U-O distance and XPS satellite intensity has been discovered. The role of flourite and octahedral crystal structures for U(IV) oxides has been examined and relationships established between XPS features and the covalent interactions in the different structures. The physical views of XPS satellites as arising from shake processes or as arising from ligand to metal charge transfers are contrasted; our analysis provides strong support that shake processes give a more fundamental physical understanding than charge transfer. Our theoretical studies are based on rigorous, strictly ab initio determinations of the electronic structure of embedded cluster models of U oxides with formal U(VI) and U(IV) oxidation states. Our results provide a foundation that makes it possible to establish quantitative relationships between features of the XPS spectra and materials properties.

Theoretical modeling of the uranium 4f XPS for U(VI) and U(IV) oxides

Science.gov (United States)

Bagus, Paul S.; Nelin, Connie J.; Ilton, Eugene S.

2013-12-01

A rigorous study is presented of the physical processes related to X-Ray photoelectron spectroscopy, XPS, in the 4f level of U oxides, which, as well as being of physical interest in themselves, are representative of XPS in heavy metal oxides. In particular, we present compelling evidence for a new view of the screening of core-holes that extends prior understandings. Our analysis of the screening focuses on the covalent mixing of high lying U and O orbitals as opposed to the, more common, use of orbitals that are nominally pure U or pure O. It is shown that this covalent mixing is quite different for the initial and final, core-hole, configurations and that this difference is directly related to the XPS satellite intensity. Furthermore, we show that the high-lying U d orbitals as well as the U(5f) orbital may both contribute to the core-hole screening, in contrast with previous work that has only considered screening through the U(5f) shell. The role of modifying the U-O interaction by changing the U-O distance has been investigated and an unexpected correlation between U-O distance and XPS satellite intensity has been discovered. The role of flourite and octahedral crystal structures for U(IV) oxides has been examined and relationships established between XPS features and the covalent interactions in the different structures. The physical views of XPS satellites as arising from shake processes or as arising from ligand to metal charge transfers are contrasted; our analysis provides strong support that shake processes give a more fundamental physical understanding than charge transfer. Our theoretical studies are based on rigorous, strictly ab initio determinations of the electronic structure of embedded cluster models of U oxides with formal U(VI) and U(IV) oxidation states. Our results provide a foundation that makes it possible to establish quantitative relationships between features of the XPS spectra and materials properties.

LEU fuel development at CERCA. Status as of October 1996: U5Si4: A new phase in the U/Si diagram

International Nuclear Information System (INIS)

Durand, J.P.; Olagnon, G.; Colomb, P.; Lavastre, Y.; Grasse, M.; Noel, H.; Queneau, V.

1996-01-01

A fundamental study has been carried out by CERCA and the French CNRS (National Scientific Research Center) as a partner in order to get a better understanding of the U 3 Si 2 casting process. On the occasion of this study, a new binary phase, U 5 Si 4 , has been discovered in the USi phase equilibrium diagram. Synthesis conditions of U 5 Si 4 have been determined and the impact of such a discovery is evaluated regarding the production process of U 3 Si 2 ingots. It can be concluded that keeping the CERCA's casting tools and within the allowed limits of production parameters, the U 3 Si 2 ingots are homogenous without any detectable trace of U 5 Si 4 even if a long term heat treatment at the hot rolling temperature is carried out. On the production point of view, perfect knowledge of both metallurgical phase synthesis and the casting process guarantee the quality of U 3 Si 2 ingots and powder produced by CERCA. (author)

Adaptable coordination of U(IV) in the 2D-(4,4) uranium oxalate network: From 8 to 10 coordinations in the uranium (IV) oxalate hydrates

International Nuclear Information System (INIS)

Duvieubourg-Garela, L.; Vigier, N.; Abraham, F.; Grandjean, S.

2008-01-01

Crystals of uranium (IV) oxalate hydrates, U(C 2 O 4 ) 2 .6H 2 O (1) and U(C 2 O 4 ) 2 .2H 2 O (2), were obtained by hydrothermal methods using two different U(IV) precursors, U 3 O 8 oxide and nitric U(IV) solution in presence of hydrazine to avoid oxidation of U(IV) into uranyl ion. Growth of crystals of solvated monohydrated uranium (IV) oxalate, U(C 2 O 4 ) 2 .H 2 O.(dma) (3), dma=dimethylamine, was achieved by slow diffusion of U(IV) into a gel containing oxalate ions. The three structures are built on a bi-dimensional complex polymer of U(IV) atoms connected through bis-bidentate oxalate ions forming [U(C 2 O 4 )] 4 pseudo-squares. The flexibility of this supramolecular arrangement allows modifications of the coordination number of the U(IV) atom which, starting from 8 in 1 increases to 9 in 3 and, finally increases, to 10 in 2. The coordination polyhedron changes from a distorted cube, formed by eight oxygen atoms of four oxalate ions, in 1, to a mono-capped square anti-prism in 3 and, finally, to a di-capped square anti-prism in 2, resulting from rotation of the oxalate ions and addition of one and two water oxygen atoms in the coordination of U(IV). In 1, the space between the ∞ 2 [U(C 2 O 4 ) 2 ] planar layers is occupied by non-coordinated water molecules; in 2, the space between the staggered ∞ 2 [U(C 2 O 4 ) 2 .2H 2 O] layers is empty, finally in 3, the solvate molecules occupy the interlayer space between corrugated ∞ 2 [U(C 2 O 4 ) 2 .H 2 O] sheets. The thermal decomposition of U(C 2 O 4 ) 2 .6H 2 O under air and argon atmospheres gives U 3 O 8 and UO 2 , respectively. - Graphical abstract: The adaptable environment of U(IV) in U(IV) oxalates: from eight cubic coordination in U(C 2 O 4 ) 2 .6H 2 O (a) completed by water oxygens to nine in [U(C 2 O 4 ) 2 .H 2 O](C 2 NH 5 ) (b) and ten coordination in U(C 2 O 4 ) 2 .2H 2 O (c)

Mathematical modeling of the radiation-chemical oxidation of U(IV) in HClO4

International Nuclear Information System (INIS)

Vladimirova, M.V.

1995-01-01

Mathematical modeling of U(IV) oxidation in 0.5-12 M HClO 4 upon α, γ-radiolysis, based on the proposed scheme of radiation-chemical reactions, has been performed. The rate constants of the U(VI) + HO 2 , U(IV) + HO 2 , U(IV) + ClO 2 , and U(IV) + ClO 2 - reactions have been determined by the comparison of the calculated and experimental kinetic and dose curves and radiation-chemical yields of U(IV) oxidation or U(VI) formation. General equations for uranium (IV) oxidation constants at various HClO 4 concentrations, based on the analysis of the rates of particular radiation-chemical reactions composing oxidation process, have been obtained

Reduction of UF4 to U-metal

International Nuclear Information System (INIS)

Namkung, H.; Min, B.T.; Kim, J.S.; Whang, S.C.

1982-01-01

In the second years of study for the production of the metallic uranium with reactors which can produce 1 Kg and 4 Kg U-metal, various factors on the yield of U-metal and the leaching condition for uranium recovery with nitric acid are examined. The jolter has been used for the charging with liner (MgF 2 ) while the hand-tamping method for the filling of reaction mixtures (UF 4 -Mg) in the reactor, and their average densities are 1.23g/cc and 2.90g/cc, respectively. The various effects on the yield such as magnesium excess, furnace control temperatue, charge densities of liner and reaction mixtures, have been studied but the yields of crude metal production are in the wide range from 93 % down to about 65 %. Generally, six percent magnesium excess produced higher yields than did either 2 or 10 percent excess. The leaching condition for the uranium recovery from slag are also investigated with dilute nitric acid (3-6N) as well as higher concentrated nitric acid (9.5N) but the leaching yields are same in either solution. Uranium recovery from the slag is very effective with dilute nitric acid (3N) leaching for less than one hour at 60degC. (Author)

The crystal structure of ianthinite, [U24+(UO2)4O6(OH)4(H2O)4](H2O)5: a possible phase for Pu4+ incorporation during the oxidation of spent nuclear fuel

International Nuclear Information System (INIS)

Burns, P.C.; Hawthorne, F.C.; Miller, M.L.; Ewing, R.C.

1997-01-01

Ianthinite, [U 4+ 2 (UO 2 ) 4 O 6 (OH) 4 (H 2 O) 4 ](H 2O) 5 , is the only known uranyl oxide hydrate mineral that contains U 4+ , and it has been proposed that ianthinite may be an important Pu 4+ -bearing phase during the oxidative dissolution of spent nuclear fuel. The crystal structure of ianthinite, orthorhombic, a=0.7178(2), b=1.1473(2), c=3.039(1) nm, V=2.5027 nm 3 , Z=4, space group P2 1 cn, has been solved by direct methods and refined by least-squares methods to an R index of 9.7% and a wR index of 12.6% using 888 unique observed [ vertical stroke F vertical stroke ≥5σ vertical stroke F vertical stroke ] reflections. The structure contains both U 6+ and U 4+ . The U 6+ cations are present as roughly linear (U 6+ O 2 ) 2+ uranyl ions (Ur) that are in turn coordinated by five O 2- and OH - located at the equatorial positions of pentagonal bipyramids. The U 4+ cations are coordinated by O 2- , OH - and H 2 O in a distorted octahedral arrangement. The Urφ 5 and U 4+ φ 6 (φ: O 2- , OH - , H 2 O) polyhedra link by sharing edges to form two symmetrically distinct sheets at z∼0.0 and z∼0.25 that are parallel to (001). The sheets have the β-U 3 O 8 sheet anion-topology. There are five symmetrically distinct H 2 O groups located at z∼0.125 between the sheets of Uφ n polyhedra, and the sheets of Uφ n polyhedra are linked together only by hydrogen bonding to the intersheet H 2 O groups. The crystal-chemical requirements of U 4+ and Pu 4+ are very similar, suggesting that extensive Pu 4+ U 4+ substitution may occur within the sheets of Uφ n polyhedra in the structure of ianthinite. (orig.)

The determination of molar volumes of uranous nitrate and nitric acid in systems of U(NO3)4-HNO3-H2O and U(NO3)4-HNO3-30% TBP kerosene

International Nuclear Information System (INIS)

Tao Chengying

1986-01-01

The data of molar volumes of uranous nitrate and nitric acid are necessary for the calculation of the changes in phase volume during the extraction in U(NO 3 ) 4 -HNO 3 /30%TBP-kerosene system. However, the data of the partial molar volume of U(NO 3 ) 4 are not available in literature. In the present work, the molar volumes of U(NO 3 ) 4 and HNO 3 are calculated by linear fitting of the experimental data. The result of the molar volume of HNO 3 is consistent with those in literature

SWIFT OBSERVATIONS OF TWO OUTBURSTS FROM THE MAGNETAR 4U 0142+61

Energy Technology Data Exchange (ETDEWEB)

Archibald, R. F.; Kaspi, V. M.; Scholz, P. [Department of Physics and McGill Space Institute, McGill University, 3600 University Street, Montreal QC, H3A 2T8 (Canada); Beardmore, A. P. [Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom); Gehrels, N. [Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Kennea, J. A., E-mail: rarchiba@physics.mcgill.ca [Department of Astronomy and Astrophysics, 525 Davey Lab, Pennsylvania State University, University Park, PA 16802 (United States)

2017-01-10

4U 0142+61 is one of a small class of persistently bright magnetars. Here, we report on a monitoring campaign of 4U 0142+61 from 2011 July 26 to 2016 June 12 using the Swift X-ray Telescope, continuing a 16-year timing campaign with the Rossi X-ray Timing Explorer . We show that 4U 0142+61 had two radiatively loud timing events, on 2011 July 29 and 2015 February 28, both with short soft γ -ray bursts, and a long-lived flux decay associated with each case. We show that the 2015 timing event resulted in a net spin-down of the pulsar that is due to overrecovery of a glitch. We compare this timing event to previous such events in other pulsars with high magnetic fields and discuss net spin-down glitches now seen in several young, high-B pulsars.

Electron Loss from 1.4 MeV/u U^4,6,10+ Ions Colliding with Ne, N₂, and Ar Targets

CERN Document Server

Dubois, R D; Stöhlker, T; Bosch, F; Bräuning-Demian, A; Banas, D; Gumberidze, A; Hagmann, S; Kozhuharov, C; Mann, R; Orsic-Muthig, A; Spillmann, U; Tachenov, S; Bart, W; Dahl, L; Franzke, B; Glatz, J; Gröning, L; Richter, S; Wilms, D; Ullmann, K; Jagutzki, O

2004-01-01

Absolute, total, single, and multiple electron loss cross sections are measured for 1.4 MeV/u U4,6,10+ ions colliding with neon and argon atoms and nitrogen molecules. It is found that the cross sections all have the same dependence on the number of electrons lost and that multiplying the cross sections by the initial number of electrons in the 6s, 6p, and 5f shells yields good agreement between the different projectiles. By combining the present data with previous measurements made at the same velocity, it is shown that the scaled cross sections slowly decrease in magnitude for incoming charge states between 1 and 10 whereas the cross sections for higher charge state ions fall off much more rapidly.

Spectrophotometric study of the formation of adducts between U(TTA)4 and neutral organosulfoxide donors

International Nuclear Information System (INIS)

Ramanujam, A.; Gudi, N.M.; Nadkarni, M.N.; Ramakrishna, V.V.; Patil, S.K.

1981-01-01

Synergistic extraction of several tetravalent actinides by mixtures of a β diketone and a neutral donor has been fairly well studied except for U(IV). Presumably, this is due to the instability of U(IV) at tracer level which does not permit the use of usual distribution methods for the study of its synergistic extraction. However, it is known that the formation of adduct between metal β diketonate and the neutral donor occurs in the organic phase and its formation is mainly responsible for the synergistic enhancement in the extraction of the metal ion. U(TTA) 4 dissolved in benzene is stable in presence of excess HTTA and addition of a neutral donor to the same results in considerable spectral changes and this has been exploited in earlier studies on the adduct formation reaction between U(TTA) 4 and several organo phosphorous neutral donors. In the present study, the adduct formation between U(TTA) 4 and few neutral sulfoxide donors: dibenzyl sulfoxide (DBSO), dimethyl sulfoxide (DMSO), dihexyl sulfoxide (DHSO) and dioctyl sulfoxide (DOSO) has been investigated in benzene medium. All the donors (S) used in the present work form 1:1 adduct with U(TTA) 4 and the equilibrium constants βsub(AB) for the reaction viz., U(TTA) 4 +S U(TTA) 4 .S have been calculated. The βsub(AB) values follow the order DBSO< DMSO< DHSP approx. DOSO. An attempt has been made to compare the values with those obtained using neutral organo phosphorous compounds and to explain the observed trends on the basis of the basicity of the neutral donors. (author)

SU(4) x U(1) gauge theory. II. CP nonconservation

International Nuclear Information System (INIS)

Deshpande, N.G.; Hwa, R.C.; Mannheim, P.D.

1979-01-01

We exploit the higher symmetry inherent in an SU(4) x U(1) gauge theory to construct a spontaneously broken theory of CP nonconservation. Higgs multiplets in the adjoint representation of SU(4) contain both even and odd CP fields; thus, requiring the simultaneous nonvanishing of the vacuum expectation values of these fields leads to CP noninvariance of the vacuum. We find that all the CP-nonconserving effects are mediated in our theory by the superheavy gauge bosons of the broken SU(4) x U(1) symmetry. In fact, the very existence of CP violation sets an upper limit on the masses of these bosons. In our model the dominant CP effect lies in the neutral kaon system and is found to arise through a direct (ΔS = 2) K 1 -K 2 transition. The model has all the features of a superweak theory, with a neutron electric dipole moment substantially smaller than 10 -24 e cm

195Pt and 119Sn Knight shifts of U3Pt3Sn4

International Nuclear Information System (INIS)

Kojima, K.; Takabatake, T.; Harada, A.; Hihara, T.

1995-01-01

The 195 Pt and 119 Sn Knight shifts in U 3 Pt 3 Sn 4 have been measured in the temperature range 4.2-298K. They exhibit Curie-Weiss like behaviors above about 50K and remain constant below about 10K. This suggests that the deviation of χ(T) from the modified Curie-Weiss law is an intrinsic property of U 3 Pt 3 Sn 4 . ((orig.))

The Chaotic Long-term X-ray Variability of 4U 1705-44

Science.gov (United States)

Phillipson, R. A.; Boyd, P. T.; Smale, A. P.

2018-04-01

The low-mass X-ray binary 4U1705-44 exhibits dramatic long-term X-ray time variability with a timescale of several hundred days. The All-Sky Monitor (ASM) aboard the Rossi X-ray Timing Explorer (RXTE) and the Japanese Monitor of All-sky X-ray Image (MAXI) aboard the International Space Station together have continuously observed the source from December 1995 through May 2014. The combined ASM-MAXI data provide a continuous time series over fifty times the length of the timescale of interest. Topological analysis can help us identify 'fingerprints' in the phase-space of a system unique to its equations of motion. The Birman-Williams theorem postulates that if such fingerprints are the same between two systems, then their equations of motion must be closely related. The phase-space embedding of the source light curve shows a strong resemblance to the double-welled nonlinear Duffing oscillator. We explore a range of parameters for which the Duffing oscillator closely mirrors the time evolution of 4U1705-44. We extract low period, unstable periodic orbits from the 4U1705-44 and Duffing time series and compare their topological information. The Duffing and 4U1705-44 topological properties are identical, providing strong evidence that they share the same underlying template. This suggests that we can look to the Duffing equation to help guide the development of a physical model to describe the long-term X-ray variability of this and other similarly behaved X-ray binary systems.

Integral benchmark test of JENDL-4.0 for U-233 systems with ICSBEP handbook

International Nuclear Information System (INIS)

Kuwagaki, Kazuki; Nagaya, Yasunobu

2017-03-01

The integral benchmark test of JENDL-4.0 for U-233 systems using the continuous-energy Monte Carlo code MVP was conducted. The previous benchmark test was performed only for U-233 thermal solution and fast metallic systems in the ICSBEP handbook. In this study, MVP input files were prepared for uninvestigated benchmark problems in the handbook including compound thermal systems (mainly lattice systems) and integral benchmark test was performed. The prediction accuracy of JENDL-4.0 was evaluated for effective multiplication factors (k eff 's) of the U-233 systems. As a result, a trend of underestimation was observed for all the categories of U-233 systems. In the benchmark test of ENDF/B-VII.1 for U-233 systems with the ICSBEP handbook, it is reported that a decreasing trend of calculated k eff values in association with a parameter ATFF (Above-Thermal Fission Fraction) is observed. The ATFF values were also calculated in this benchmark test of JENDL-4.0 and the same trend as ENDF/B-VII.1 was observed. A CD-ROM is attached as an appendix. (J.P.N.)

Determination of uranium concentrations and "2"3"4U/"2"3"8U activity ratio in some granitic rock samples by alpha spectrometry: application of a radiochemical procedure

International Nuclear Information System (INIS)

Khattab, Mahmoud R.

2016-01-01

The present study is an application of a radiochemical procedure using alpha spectrometry technique for determination of uranium isotopes "2"3"8U, "2"3"4U and "2"3"5U on 13 granitic samples. These samples were collected from Gabal Gattar area, Northeastern Desert, Egypt. The collected samples were digested using microwave technique with aqua regia and spiked with "2"3"2U for chemical yield and activity calculation. Separation of uranium isotopes from the samples was done by Dowex 1 x 4 (50-100 mesh) resin followed by source preparation using microprecipitation technique. The concentrations of "2"3"8U were ranged between 28.9±0.9 and 134.8±1.8 Bq/g, and the "2"3"4U concentrations were between 24±0.6 and 147.7±2.2 Bq/g. For the "2"3"5U, the activity concentrations were between 1.3±0.2 and 6.7±1.2 Bq/g. The activity ratio of "2"3"4U/"2"3"8U was calculated and varied from 0.80 to 1.30. (author)

Synthesis of (R)-5-(Di[2,3-3H2]propylamino)-5,6-dihydro-4H-imidazo[4,5,1-ij]quinolin-2(1H)-one-([3H]U-86170) and (R)-5-([2,3-3H2]propylamino)-5,6-dihydro-4H-imidazo(4,5,1-ij) quinolin-2(1H)-one ([3H]U-91356)

International Nuclear Information System (INIS)

Moon, M.W.; Hsi, R.S.P.

1992-01-01

(R)-5-(diallylamino)-5,6-dihydro-4H-imidazo[4,5,1-ij]quinolin-2(1H)-one (12b) was prepared in 9% overall yield from 3-aminoquinoline. Reaction of 12b in ethyl acetate with tritium gas in presence of a 5% platinum on carbon catalyst afforded a mixture of (R)-5-(di[2,3- 3 H 2 ]propylamino)-5,6-dihydro-4H-imidazo[4,5,1-ij]-quinolin-2(1H)-one ([ 3 H]U-86170, 69 Ci/mmol) and (R)-5-([2,3- 3 H 2 ]-propylamino)5,6-dihydro-4H-imidazo-[4,5,1-ij]quinolin-2(1H)-one ( [ 3 H]U-91356, 34 Ci/mmol) which was separated by preparative reverse-phase chromatography. U-86170 and U-91356 are potent dopamine D2 agonists. The labelled compounds are useful for drug disposition studies. [ 3 H]U-86170 is also useful as a dopamine D2 agonist radioligand for receptor binding studies. (author)

Involvement of reversible binding to alpha 2u-globulin in 1,4-dichlorobenzene-induced nephrotoxicity.

Science.gov (United States)

Charbonneau, M; Strasser, J; Lock, E A; Turner, M J; Swenberg, J A

1989-06-01

Similarly to unleaded gasoline, 1,4-dichlorobenzene (1,4-DCB) administered for 2 years caused a dose-related increase in the incidence of renal tumors in male but not in female rats or in either sex of mice. Unleaded gasoline and 2,2,4-trimethylpentane (TMP), a component of unleaded gasoline, increased protein droplet formation and cell proliferation in male but not in female rat kidneys. These protein droplets contained, alpha 2u-globulin, a male rat-specific low-molecular-weight protein and 2,4,4-trimethyl-2-pentanol, a metabolite of TMP that was reversibly bound to this protein. Studies were undertaken to determine if 1,4-DCB produced similar effects; 1,2-DCB was used for comparison since it did not produce renal carcinogenesis in male rats. Gel filtration chromatography of a 116,000g supernatant prepared from kidneys of 1,4-[14C]DCB-treated rats showed that radiolabel coeluted with alpha 2u-globulin as one sharp peak as opposed to a multipeak pattern observed for 1,2-[14C]DCB; the maximal quantity of radiolabel for 1,4-DCB was twice that for 1,2-DCB. Equilibrium dialysis of kidney cytosol in the presence or absence of sodium dodecyl sulfate demonstrated that the radiolabel was reversibly bound to alpha 2u-globulin; the amount for 1,4-[14C]DCB-treated rats was almost twice as much as that for 1,2-[14C]DCB-treated rats. 1,2-DCB was also shown to be covalently bound to renal alpha 2u-globulin, and covalently bound to liver and plasma high-molecular-weight proteins. 1,4-DCB and, to a minor extent, 2,5-dichlorophenol, the major metabolite of 1,4-DCB, were reversibly bound to renal alpha 2u-globulin from 1,4-DCB-treated rats. 1,4-DCB increased protein droplet formation in male but not in female rat kidneys, whereas equimolar doses of 1,2-DCB showed no effect in either sex. Renal cell proliferation, measured by [3H]thymidine incorporation into renal DNA, was increased after 1,4-DCB but not after 1,2-DCB treatment. Nephrotoxicity and biochemical alterations induced by

16 CFR 1608.4 - Guaranties furnished by nonresidents of the U.S. no bar to prosecution.

Science.gov (United States)

2010-01-01

... U.S. no bar to prosecution. 1608.4 Section 1608.4 Commercial Practices CONSUMER PRODUCT SAFETY... § 1608.4 Guaranties furnished by nonresidents of the U.S. no bar to prosecution. A guaranty furnished... as a bar to prosecution under section 7 of the act for a violation of section 3 of the act. ...

The system AM HER = 4U 1814 + 50

International Nuclear Information System (INIS)

Chiappetti, L.; Tanzi, E.G.; Treves, A.; Consiglio Nazionale delle Ricerche, Milan

1980-01-01

The binary system AM Herculis = 4U 1814 + 50 gives the first well ascertained example of an X-ray emitting magnetic white dwarf. The orbital period (3.1sup(h)) is apparent from X-ray to IR frequencies and in linear and circular polarization. Since the time of the identification of the X-ray source the system has been extensively studied. The observations (which range from 1 MeV to 20 μm) are reviewed and compared with the present theory of X-ray emitting white dwarfs. (orig.)

Structural and electronic response of U{sub 3}Fe{sub 4}Ge{sub 4} to high pressure

Energy Technology Data Exchange (ETDEWEB)

Henriques, M. S., E-mail: henriques@fzu.cz [Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague (Czech Republic); CCTN, IST/CFMCUL, University of Lisbon, Nuclear and Technological Campus, P-2695-066 Bobadela (Portugal); Gorbunov, D. I.; Andreev, A. V.; Arnold, Z. [Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague (Czech Republic); Prchal, J.; Havela, L. [Faculty of Mathematics and Physics, Department of Condensed Matter Physics, Charles University in Prague, Ke Karlovu 5, 121 16 Prague (Czech Republic); Raison, P.; Heathman, S.; Griveau, J.-C.; Colineau, E. [European Commission, Joint Research Centre, Institute for Transuranium Elements, Postfach 2340, 76125 Karlsruhe (Germany); Gonçalves, A. P. [CCTN, IST/CFMCUL, University of Lisbon, Nuclear and Technological Campus, P-2695-066 Bobadela (Portugal)

2015-03-21

Structural, magnetic, and electrical properties have been studied on a U{sub 3}Fe{sub 4}Ge{sub 4} single crystal under hydrostatic pressure. The orthorhombic crystal structure is found to be stable up to 30 GPa, the highest applied pressure, but the compressibility is strongly anisotropic. Contrary to typical uranium intermetallics for which the softest lattice direction is along the shortest inter-uranium links, in U{sub 3}Fe{sub 4}Ge{sub 4} the lattice is compressed most in a perpendicular direction for the high pressure range. The elastic properties are modified considerably in the vicinity of 1 GPa when the b axis is transformed from least compressible to most compressible. The bulk modulus is found to be about 150 GPa. The anomalies in the elastic properties are reflected in the electronic properties that consistently indicate a change of the magnetic ground state from ferromagnetic to antiferromagnetic. Both types of order exhibit a gap in the magnon spectrum; however, it is twice as high for the ferromagnetic state. The magnetoresistance reveals field-induced transitions of different origins in the antiferromagnetic state along the easy and hard magnetization directions.

Sequential application of ligand and structure based modeling approaches to index chemicals for their hH4R antagonism.

Directory of Open Access Journals (Sweden)

Matteo Pappalardo

Full Text Available The human histamine H4 receptor (hH4R, a member of the G-protein coupled receptors (GPCR family, is an increasingly attractive drug target. It plays a key role in many cell pathways and many hH4R ligands are studied for the treatment of several inflammatory, allergic and autoimmune disorders, as well as for analgesic activity. Due to the challenging difficulties in the experimental elucidation of hH4R structure, virtual screening campaigns are normally run on homology based models. However, a wealth of information about the chemical properties of GPCR ligands has also accumulated over the last few years and an appropriate combination of these ligand-based knowledge with structure-based molecular modeling studies emerges as a promising strategy for computer-assisted drug design. Here, two chemoinformatics techniques, the Intelligent Learning Engine (ILE and Iterative Stochastic Elimination (ISE approach, were used to index chemicals for their hH4R bioactivity. An application of the prediction model on external test set composed of more than 160 hH4R antagonists picked from the chEMBL database gave enrichment factor of 16.4. A virtual high throughput screening on ZINC database was carried out, picking ∼ 4000 chemicals highly indexed as H4R antagonists' candidates. Next, a series of 3D models of hH4R were generated by molecular modeling and molecular dynamics simulations performed in fully atomistic lipid membranes. The efficacy of the hH4R 3D models in discrimination between actives and non-actives were checked and the 3D model with the best performance was chosen for further docking studies performed on the focused library. The output of these docking studies was a consensus library of 11 highly active scored drug candidates. Our findings suggest that a sequential combination of ligand-based chemoinformatics approaches with structure-based ones has the potential to improve the success rate in discovering new biologically active GPCR drugs and

Sequential application of ligand and structure based modeling approaches to index chemicals for their hH4R antagonism.

Science.gov (United States)

Pappalardo, Matteo; Shachaf, Nir; Basile, Livia; Milardi, Danilo; Zeidan, Mouhammed; Raiyn, Jamal; Guccione, Salvatore; Rayan, Anwar

2014-01-01

The human histamine H4 receptor (hH4R), a member of the G-protein coupled receptors (GPCR) family, is an increasingly attractive drug target. It plays a key role in many cell pathways and many hH4R ligands are studied for the treatment of several inflammatory, allergic and autoimmune disorders, as well as for analgesic activity. Due to the challenging difficulties in the experimental elucidation of hH4R structure, virtual screening campaigns are normally run on homology based models. However, a wealth of information about the chemical properties of GPCR ligands has also accumulated over the last few years and an appropriate combination of these ligand-based knowledge with structure-based molecular modeling studies emerges as a promising strategy for computer-assisted drug design. Here, two chemoinformatics techniques, the Intelligent Learning Engine (ILE) and Iterative Stochastic Elimination (ISE) approach, were used to index chemicals for their hH4R bioactivity. An application of the prediction model on external test set composed of more than 160 hH4R antagonists picked from the chEMBL database gave enrichment factor of 16.4. A virtual high throughput screening on ZINC database was carried out, picking ∼ 4000 chemicals highly indexed as H4R antagonists' candidates. Next, a series of 3D models of hH4R were generated by molecular modeling and molecular dynamics simulations performed in fully atomistic lipid membranes. The efficacy of the hH4R 3D models in discrimination between actives and non-actives were checked and the 3D model with the best performance was chosen for further docking studies performed on the focused library. The output of these docking studies was a consensus library of 11 highly active scored drug candidates. Our findings suggest that a sequential combination of ligand-based chemoinformatics approaches with structure-based ones has the potential to improve the success rate in discovering new biologically active GPCR drugs and increase the

Modeling of punctual defects in UAL4 from the U-Al system: Combination of CALPHAD method with first principles calculation

International Nuclear Information System (INIS)

Kniznik, L; Alonso, P.R; Gargano, P.H; Rubiolo, G.H.

2012-01-01

We investigated the point defect structure of oI20 UAl 4 in order to study aluminum diffusion. We performed ab initio calculations within a pseudopotentials method implemented in the Vienna Ab initio Simulation Package (VASP) to obtain point defect formation energies: vacancies (V U and V A l ) and antisites (Al U and U A l). Using a statistical-thermodynamic model we calculated defects concentrations as function of temperature and deviation from stoichiometry. For stoichiometric UAl 4 antisites are the dominant thermal defects. In off-stoichiometric UAl 4 , antisites are the constitutional defects. For U-rich UAl 4 , the thermal defect is called Entre Ramas, where one antisite U atom is replaced by five Al vacancies. For Al-rich UAl 4 , the thermal defect is also an Entre Ramas, where four antisite Al atoms are replaced by five U vacancies. Our first principles results were used to model UAl 4 intermediate phase with a two sublattices Wagner-Schottky model. The Thermocalc data bases previously used were modified, including antisites and vacancies in both sublattices of the UAl 4 intermediate phase: (U,Al,VA) 0.2 : (Al,U,VA) 0.8 . We obtained a consistent thermodynamic database able to reproduce the entire U-Al equilibrium phase diagram (author)

Hydrogeochemical utilization of natural isotopes from U(4n+2) and Th(4n) series at Morro do Ferro, Pocos de Caldas (MG)

International Nuclear Information System (INIS)

Bonotto, D.M.

1991-01-01

Uranium and thorium isotopic analysis were performed on well spoils of the main ore body at Morro do Ferro, Pocos de Caldas (MG), using groundwater from several boreholes in the area and surface water from a steam that originates at the base of the hill. For extraction of uranium and thorium a long chemical process was applied to samples; activities of 228Th and 232 Th isotopes (4n series) and also of 238U, 234U and 230Th isotopes (4n+2 series)were determined by the alpha spectrometry method. The ratios 234U?238U determined for well spoils did not show marked disequilibria between these isotopes. However, the ratios 228Th/232Th and 230Th/234U obtained in some samples showed a high disequilibrium between these isotopes, associated with the presence of possible zones of removal of uranium and precipitation of radium.(author)

Microstructure studies of interdiffusion behavior of U{sub 3}Si{sub 2}/Zircaloy-4 at 800 and 1000 °C

Energy Technology Data Exchange (ETDEWEB)

He, Lingfeng, E-mail: Lingfeng.He@inl.gov; Harp, Jason M., E-mail: Jason.Harp@inl.gov; Hoggan, Rita E.; Wagner, Adrian R.

2017-04-01

Fuel swelling during normal reactor operations could lead to unfavorable chemical interactions when in contact with its cladding. As new fuel types are developed, it is crucial to understand the interaction behavior between fuel and its cladding. Diffusion experiments between U{sub 3}Si{sub 2} and Zricaloy-4 (Zry-4) were conducted at 800 and 1000 °C up to 100 h. The microstructure of pristine U{sub 3}Si{sub 2} and U{sub 3}Si{sub 2}/Zry-4 interdiffusion products were examined using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) equipped with an energy dispersive X-ray spectroscopy (EDS) system. The primary interdiffusion product observed at 800 °C is ZrSi{sub 2}, with secondary phases of U-Zr in the Zry-4, and Fe-Cr-W-Zr-Si phases at Zry-4/ZrSi{sub 2} interface and Fe-Cr-U-Si phases at ZrSi{sub 2}/U-Si interface. The primary interdiffusion products at 1000 °C were Zr{sub 2}Si, U-Zr-Fe-Ni, U, U-Zr, and a low melting point phase U{sub 6}Fe.

Optical pulsations from 4U 0900--40: Do they exist

International Nuclear Information System (INIS)

Nelson, J.; Middleditch, J.; Cordova, F.

1979-01-01

A search for optical pulsations from 4U 0900--40 (HD 77581) was made in 1977--1978 using Hβ interference filters. No pulsations were detected above 10 -3 of the observed flux. This contrasts with Steiner's detection of pulsatons at the 2% level. Ariel 5 data covering both our observations and Steiner's show that X-ray variability does not support this decrepancy

Nitric acid titration in the presence of UO2(NO3)2, Th(NO3)4, U(NO3)4 or Zr(NO3)4

International Nuclear Information System (INIS)

Nakashima, T.; Lieser, K.H.

1986-01-01

Procedures are described for titration of HNO 3 in presence of UO 2 2+ , Th 4+ , U 4+ and Zr 4+ without formation of interfering precipitates. In the first step the hydrolysable ions are masked by addition of complexing agents and in the second step the acid is titrated by NaOH as usual. (orig.)

Correlated Radial Velocity and X-Ray Variations in HD 154791/4U 1700+24

Science.gov (United States)

Galloway, Duncan K.; Sokoloski, J. L.; Kenyon, Scott J.

2002-12-01

We present evidence for approximately 400 day variations in the radial velocity of HD 154791 (V934 Her), the suggested optical counterpart of 4U 1700+24. The variations are correlated with the previously reported ~400 day variations in the X-ray flux of 4U 1700+24, which supports the association of these two objects, as well as the identification of this system as the second known X-ray binary in which a neutron star accretes from the wind of a red giant. The HD 154791 radial velocity variations can be fitted with an eccentric orbit with period 404+/-3 days, amplitude K=0.75+/-0.12kms-1, and eccentricity e=0.26+/-0.15. There are also indications of variations on longer timescales >~2000 days. We have reexamined all available All-Sky Monitor (ASM) data following an unusually large X-ray outburst in 1997-1998 and confirm that the 1 day averaged 2-10 keV X-ray flux from 4U 1700+24 is modulated with a period of 400+/-20 days. The mean profile of the persistent X-ray variations was approximately sinusoidal, with an amplitude of 0.108+/-0.012 ASM counts s-1 (corresponding to 31% rms). The epoch of X-ray maximum was approximately 40 days after the time of periastron, according to the eccentric orbital fit. If the 400 day oscillations from HD 154791/4U 1700+24 are due to orbital motion, then the system parameters are probably close to those of the only other neutron star symbiotic-like binary, GX 1+4. We discuss the similarities and differences between these two systems.

Evidence for a Millisecond Pulsar in 4U 1636-53 During a Superburst

Science.gov (United States)

Strohmayer, Tod E.; Markwardt, Craig B.; White, Nicholas E. (Technical Monitor)

2002-01-01

We report the discovery with the Proportional Counter Array on board the Rossi X-ray Timing Explorer of highly coherent 582 Hz pulsations during the February 22, 2001 (UT) 'superburst' from 4U 1636-53. The pulsations are detected during an 800 s interval spanning the flux maximum of the burst. Within this interval the barycentric oscillation frequency increases in a monotonic fashion from 581.89 to 581.93 Hz. The predicted orbital motion of the neutron star during this interval is consistent with such an increase as long as optical maximum corresponds roughly with superior conjunction of V801 Arae, the optical companion to the neutron star in 4U 1636-53. We show that a range of circular orbits with 90 phi(sub 0) > 0.277 for the neutron star can provide an excellent description of the frequency and phase evolution. The brevity of the observed pulse train with respect to the 3.8 hour orbital period unfortunately does not allow more precise constraints. The average pulse profile is sinusoidal and the time averaged pulsation amplitude, as inferred from the half amplitude of the sinusoid is 1%, smaller than typical for burst oscillations observed in normal thermonuclear bursts. We do not detect any higher harmonics nor the putative subharmonic near 290 Hz. The 90% upper limits on signal amplitude at the subharmonic and first harmonic are 0.1 and 0.06%, respectively. The highly coherent pulsation, with a Q = v(sub 0)/delta-v > 4.5 x 10(exp 5) provides compelling evidence for a rapidly rotating neutron star in 4U 1636-53, and further supports the connection of burst oscillation frequencies with the spin frequencies of neutron stars. Our results provide further evidence that some millisecond pulsars are spun up via accretion in LMXBs. We also discuss the implications of our orbital velocity constraint for the masses of the components of 4U 1636-53.

Milestone Report - Complete New Adsorbent Materials for Marine Testing to Demonstrate 4.5 g-U/kg Adsorbent

Energy Technology Data Exchange (ETDEWEB)

Janke, Christopher James [ORNL; Das, Sadananda [ORNL; Oyola, Yatsandra [ORNL; Mayes, Richard T. [ORNL; Saito, Tomonori [ORNL; Brown, Suree [ORNL; Gill, Gary [PNNL; Kuo, Li-Jung [PNNL; Wood, Jordana [PNNL

2014-08-01

This report describes work on the successful completion of Milestone M2FT-14OR03100115 (8/20/2014) entitled, “Complete new adsorbent materials for marine testing to demonstrate 4.5 g-U/kg adsorbent”. This effort is part of the Seawater Uranium Recovery Program, sponsored by the U.S. Department of Energy, Office of Nuclear Energy, and involved the development of new adsorbent materials at the Oak Ridge National Laboratory (ORNL) and marine testing at the Pacific Northwest National Laboratory (PNNL). ORNL has recently developed two new families of fiber adsorbents that have demonstrated uranium adsorption capacities greater than 4.5 g-U/kg adsorbent after marine testing at PNNL. One adsorbent was synthesized by radiation-induced graft polymerization of itaconic acid and acrylonitrile onto high surface area polyethylene fibers followed by amidoximation and base conditioning. This fiber showed a capacity of 4.6 g-U/kg adsorbent in marine testing at PNNL. The second adsorbent was prepared by atom-transfer radical polymerization of t-butyl acrylate and acrylonitrile onto halide-functionalized round fibers followed by amidoximation and base hydrolysis. This fiber demonstrated uranium adsorption capacity of 5.4 g-U/kg adsorbent in marine testing at PNNL.

CNEA developments in U-Mo-ZrY-4 mini plates and plates fabrication process

International Nuclear Information System (INIS)

López, M.; Picchetti, B.; Gonzalez, A.; Taboada, H.

2013-01-01

The Uranium Molybdenum alloy was the material chosen to develop the fabrication of high density nuclear fuel, due to its excellent behaviour under irradiation –a consequence of the metastable bcc crystalline structure-. At present, the study is focused on the application of this alloy to monolithic fuel plate development, which fuel core is a thin U-Mo layer. The Zircalloy-4 (Zry-4) alloy used as cladding material is extensively known in the nuclear industry due to its low neutron capture section efficiency and excellent mechanical and corrosion resistance properties. Miniplates fabrication process involves a welded compact made of two Zry-4 covers and a frame surrounding a monolithic U-Mo core, which is co rolled under high temperature. Molybdenum contains of 7% to 10% (mass) in U Mo alloys guarantees the presence of meta-stable bcc gamma phase and, at the same time, does not penalize the neutron economy due to Mo98 presence. In the case of U Mo monolithic miniplates relevant parameters of fabrication, considering the behaviour of the U-Mo alloys reported in many work and in order to optimize the o-rolling process, have been revised: co-rolling temperature, compressive stress and presence of gap. Under this experimental conditions can be studied the the interdiffusion layer, the binding between materials and the Dog Bone. The experimental results shows that 650ºC is an optimal co-rolling temperature; at higher temperatures not only a bigger interdiffusion layer is observed –this phenomenon can lead to a region enriched in Molybdenum- but also a bigger Dog Bone is obtained. Working at higher compressive stress has the same effect in relation to the interdiffusion layer. In addition, the absence of gases in the core is essential for the correct binding of the materials. Concerning the monolithic U-Mo plates fabrication, involved in the ALT FUTURE experiment a new workshop has been conditioned. The aim is to use all the valuable information collected during

F4U production by electrolytic reduction

International Nuclear Information System (INIS)

Esteban Duque, A.; Gispert Benach, M.; Hernandez Arroyo, F.; Montes Ponce de Leon, M.; Rojas de Diego, J. L.

1974-01-01

As a part of the nuclear fuel cycle program developed at the Spanish Atomic Energy Commission it has been studied the electrolytic reduction of U-VI to U-IV. The effect of the materials, electrolyte concentration, pH, current density, cell size and laboratory scale production is studied. The Pilot Plant and the production data are also described. (Author) 18 refs

Basic study on apoptosis induction into cancer cells U-937 and EL-4 by ultrasound exposure.

Science.gov (United States)

Takeuchi, Shinichi; Udagawa, Yoshiko; Oku, Yumiko; Fujii, Takuma; Nishimura, Hiroyuki; Kawashima, Norimichi

2006-12-22

Recently, the low invasive cancer treatments with small aftereffects have been considered. We are studying on the suppression methods of cancer cell proliferation with ultrasound. Cancer cells of mouse T lymphoma (EL-4) have been used in our study. The human histitocytic lymphoma cells (U-937) was used in this time. The cancer cells were cultured in a culture medium of RPMI1640. The standing wave acoustic field was formed in a water tank of our ultrasound exposure system by a vibrating plate driven with a Langevine type transducer. The U-937 and EL-4 were exposed to ultrasound in the acoustic field with spatial average acoustic intensity of 350 mW/cm(2) at 150 kHz. The viable rate of EL-4 decreased with the lapse of culture time after ultrasound exposure. U-937 did not show the remarkable decrease tendency. The proliferation of U-937 which exposed to ultrasound with 700 mW/cm(2) was suppressed. It can be thought that apoptosis was induced in the cancer cells in this condition. We observed the morphological change on the U-937 exposed to ultrasound with this condition. The morphological changes by apoptosis like the shrink of cells, formation of apoptotic bodies etc. can be observed with an optical microscope and a phase contrast microscope.

A 4 U Laser Heterodyne Radiometer for Methane (CH4) and Carbon Dioxide (CO2) Measurements from an Occultation-Viewing CubSat

Science.gov (United States)

Wilson, Emily L.; DiGregorio, A. J.; Riot, Vincent J.; Ammons, Mark S.; Bruner, WIlliam W.; Carter, Darrell; Mao, Jianping; Ramanathan, Anand; Strahan, Susan E.; Oman, Luke D.;

Accelerated electron exchange between U4+ and UO22+ by foreign metal ions

International Nuclear Information System (INIS)

Obanawa, Heiichiro; Onitsuka, Hatsuki; Takeda, Kunihiko

1990-01-01

The rate constant of U 4+ -UO 2 2+ electron exchange (k et ) was increased by more than 100 times in the presence of various metal ions. The larger rate constant was observed for the smaller difference of the standard reduction potential strength between metal ion and UO 2 2+ ion (Δμ θ e ). Detailed investigation of the electron exchange reaction in the presence of Mo 5+ suggested that the mechanism of the electron transfer reaction catalyzed by metal ions is the outer-sphere type independent of U-Clcomplex ions. (author)

Speciation in the aqueous H+/H2VO4-/H2O2/citrate system of biomedical interest.

Science.gov (United States)

Gorzsás, András; Getty, Kendra; Andersson, Ingegärd; Pettersson, Lage

2004-09-21

The speciation in the quaternary aqueous H+/H2VO4-/H2O2/citrate (Cit3-) and H+/H2VO4-/Cit3-/L-(+)-lactate (Lac-) systems has been determined at 25 degrees C in the physiological medium of 0.150 M Na(Cl). A combination of 51V NMR integral intensities and chemical shift (Bruker AMX500) as well as potentiometric data (glass electrode) have been collected and evaluated with the computer program LAKE, which is able to treat multimethod data simultaneously. The pKa-values for citric acid have been determined as 2.94, 4.34 and 5.61. Altogether six vanadate-citrate species have been found in the ternary H+/H2VO4-/Cit3- system in the pH region 2-10, only two of which are mononuclear. Reduction of vanadium(V) becomes more pronounced at pH acidic solutions limited the final model to pH > 4. In the quaternary H+/H2VO4-/Cit3-/Lac- system, two mixed-ligand species have been determined, with the compositions V2CitLac2- and V2CitLac3- (pKa = 5.0). To our knowledge, this is the first time such complexes have been reported for vanadium(V). 51V NMR chemical shifts, compositions and formation constants are given, and equilibrium conditions are illustrated in distribution diagrams as well as the fit of the model to the experimental data. When suitable, structural proposals are given, based on 13C NMR measurements and available literature data of related compounds.

U(1) decoupling, Kleiss-Kuijf and Bern-Carrasco-Johansson relations in N=4 super Yang-Mills

International Nuclear Information System (INIS)

Jia Yin; Huang Rijun; Liu Changyong

2010-01-01

By using the Britto-Cachazo-Feng-Witten recursion relation of N=4 super Yang-Mills theory, we proved the color reflection, U(1) decoupling, Kleiss-Kuijf and Bern-Carrasco-Johansson relations for color-ordered amplitudes of N=4 super Yang-Mills theory. This proof verified the conjectured Bern-Carrasco-Johansson relations of matter fields. The proof depended only on general properties of superamplitudes. We showed also that the color reflection relation and U(1)-decoupling relation are special cases of Kleiss-Kuijf relations.

Metallurgical characterization of melt-spun ribbons of U-5.4 wt%Nb alloy

Science.gov (United States)

Ma, Rong; Ren, Zhiyong; Tang, Qingfu; Chen, Dong; Liu, Tingyi; Su, Bin; Wang, Zhenhong; Luo, Chao

2018-06-01

The microstructures and micro-mechanical properties of the melt-spun ribbons of U-5.4 wt%Nb alloy were characterized using optical microscopy, scanning electron microscopy, X-ray diffraction and nanoindentation. Observed variations in microstructures and properties are related to the changes in ribbon thicknesses and cooling rates. The microstructures of the melt-spun ribbon consist of fine-scale columnar grains (∼1 μm) adjacent to the chill surface and coarse cellular grains in the remainder of the ribbon. In addition, the formation of inclusions in the ribbon is suppressed kinetically due to the high cooling rate during melt spinning. Compared with the water-quenched specimen prepared by traditional gravity casting and solution heat treatment, the elastic modulus values of the U-5.4 wt%Nb alloy were examined to vary with grain size and exhibited diverse energy dissipation capacities.

A 4 U laser heterodyne radiometer for methane (CH4) and carbon dioxide (CO2) measurements from an occultation-viewing CubeSat

International Nuclear Information System (INIS)

Wilson, Emily L; Oman, Luke D; DiGregorio, A J; Garner, Richard M; Riot, Vincent J; Ammons, Mark S; Bruner, William W; Carter, Darrell; Mao, Jianping; Ramanathan, Anand; Strahan, Susan E; Hoffman, Christine

2017-01-01

We present a design for a 4 U (20 cm  ×  20 cm  ×  10 cm) occultation-viewing laser heterodyne radiometer (LHR) that measures methane (CH 4 ), carbon dioxide (CO 2 ) and water vapor (H 2 O) in the limb that is designed for deployment on a 6 U CubeSat. The LHR design collects sunlight that has undergone absorption by the trace gas and mixes it with a distributive feedback (DFB) laser centered at 1640 nm that scans across CO 2 , CH 4 , and H 2 O absorption features. Upper troposphere/lower stratosphere measurements of these gases provide key inputs to stratospheric circulation models: measuring stratospheric circulation and its variability is essential for projecting how climate change will affect stratospheric ozone. (paper)

A 4 U laser heterodyne radiometer for methane (CH4) and carbon dioxide (CO2) measurements from an occultation-viewing CubeSat

Science.gov (United States)

Wilson, Emily L.; DiGregorio, A. J.; Riot, Vincent J.; Ammons, Mark S.; Bruner, William W.; Carter, Darrell; Mao, Jianping; Ramanathan, Anand; Strahan, Susan E.; Oman, Luke D.; Hoffman, Christine; Garner, Richard M.

2017-03-01

We present a design for a 4 U (20 cm  ×  20 cm  ×  10 cm) occultation-viewing laser heterodyne radiometer (LHR) that measures methane (CH4), carbon dioxide (CO2) and water vapor (H2O) in the limb that is designed for deployment on a 6 U CubeSat. The LHR design collects sunlight that has undergone absorption by the trace gas and mixes it with a distributive feedback (DFB) laser centered at 1640 nm that scans across CO2, CH4, and H2O absorption features. Upper troposphere/lower stratosphere measurements of these gases provide key inputs to stratospheric circulation models: measuring stratospheric circulation and its variability is essential for projecting how climate change will affect stratospheric ozone.

3d-4f magnetic interaction with density functional theory plus u approach: local Coulomb correlation and exchange pathways.

Science.gov (United States)

Zhang, Yachao; Yang, Yang; Jiang, Hong

2013-12-12

The 3d-4f exchange interaction plays an important role in many lanthanide based molecular magnetic materials such as single-molecule magnets and magnetic refrigerants. In this work, we study the 3d-4f magnetic exchange interactions in a series of Cu(II)-Gd(III) (3d(9)-4f(7)) dinuclear complexes based on the numerical atomic basis-norm-conserving pseudopotential method and density functional theory plus the Hubbard U correction approach (DFT+U). We obtain improved description of the 4f electrons by including the semicore 5s5p states in the valence part of the Gd-pseudopotential. The Hubbard U correction is employed to treat the strongly correlated Cu-3d and Gd-4f electrons, which significantly improve the agreement of the predicted exchange constants, J, with experiment, indicating the importance of accurate description of the local Coulomb correlation. The high efficiency of the DFT+U approach enables us to perform calculations with molecular crystals, which in general improve the agreement between theory and experiment, achieving a mean absolute error smaller than 2 cm(-1). In addition, through analyzing the physical effects of U, we identify two magnetic exchange pathways. One is ferromagnetic and involves an interaction between the Cu-3d, O-2p (bridge ligand), and the majority-spin Gd-5d orbitals. The other one is antiferromagnetic and involves Cu-3d, O-2p, and the empty minority-spin Gd-4f orbitals, which is suppressed by the planar Cu-O-O-Gd structure. This study demonstrates the accuracy of the DFT+U method for evaluating the 3d-4f exchange interactions, provides a better understanding of the exchange mechanism in the Cu(II)-Gd(III) complexes, and paves the way for exploiting the magnetic properties of the 3d-4f compounds containing lanthanides other than Gd.

DNA sequence analysis of the mutational specificity of u.v. light in the SUP4-o gene of yeast

International Nuclear Information System (INIS)

Kunz, B.A.; Mis, J.R.A.; Pierce, M.K.; Giroux, C.N.

1987-01-01

Mutations induced in the SUP4-o gene of Saccharomyces cerevisiae by u.v. irradiation have been characterized. DNA sequence analysis of 120 mutants revealed that u.v. induced all types of base substitutions, although transitions, in particular G:C → A:T events predominated. In addition, a small number of single base pair deletions and double mutations, occurring in tandem or separated by a few base pairs, were recovered. The base pair substitutions were not distributed randomly in the SUP4-o gene and, with one exception, were all located at sites of adjacent pyrimidines, suggesting they were targeted by u.v. photolesions. A substantial fraction of the mutations were detected at hotspots for u.v. mutagenesis. The majority of changes occurred at the 3' base of dipyrimidine sequences where both cyclobutane dimers and [6-4]-photoproducts could form. Approximately one-third of the induced base substitutions were found at potential pyrimidine dimer sites where [6-4]-photoproducts would be expected to occur rarely. Possible origins of the induced mutations and the role of cyclobutane dimers as premutational u.v. lesions in yeast are considered. (author)

Neutrino masses in the flipped SU(5) x U(1) and the SU(4) x O(4) GUT models

Energy Technology Data Exchange (ETDEWEB)

Ranfone, S.; Papageorgiu, E.

1992-03-01

We classify the different neutrino-mass pattern arising in string-inspired Grand Universal Theory (GUT) and supersymmetric GUT models based on the flipped SU(5)xU(1) and the SU(4)xO(4) gauge groups. Phenomenologically interesting spectra are obtained through the interplay of the two seesaw mechanisms present, with typical neutrino masses {approx}10{sup -3} eV in the supersymmetric GUT models and of order 0.1 - 10 KeV in the ordinary GUTs. (author).

Neutrino masses in the flipped SU(5)xU(1) and the SU(4)xO(4) GUT models

Energy Technology Data Exchange (ETDEWEB)

Papageorgiu, E.; Ranfone, S. (Rutherford Appleton Lab., Chilton (United Kingdom))

1992-05-21

We classify the different neutrino-mass patterns arising in string-inspired GUT and supersymmetric GUT models based on the flipped SU(5)xU(1) and the SU(4)xO(4) gauge groups. Phenomenologically interesting spectra are obtained through the interplay of the two seesaw mechanisms present, with typical neutrino masses {proportional to}10{sup -3} eV in the supersymmetric GUT models and of order 0.1-10 keV in the ordinary GUTs. (orig.).

Quantification of "2"3"2Th, "2"3"4U, "2"3"5U and "2"3"8U in river mollusks by magnetic sector mass spectrometry with inductively coupled plasma source (Icp-SFMS)

International Nuclear Information System (INIS)

Arevalo R, D. L.; Hernandez M, H.; Romero G, E. T.; Lara A, N.; Alfaro de la T, M. C.

2016-09-01

The present work deals with the methodology established for the quantification of "2"3"2Th, "2"3"4U, "2"3"8U and "2"3"5U in the shell of gastropod mollusks collected in the rivers Valles, Coy and Axtla of San Luis Potosi, Mexico, which belong to the Panuco River basin; these rivers have as main source of pollution the discharge of municipal sewage, waste from small industries, agricultural and cattle residues and from natural sources. Conventional methods for measuring radio-nuclides are confronted with certain conditions related to the requirement in measurement, basically in the characterization that is related to the concepts of precision and accuracy. The analysis of the gastropod mollusk shell was performed by the Icp-SFMS technique; the main advantages of this technique lie in the isotope quantification capacity, the high precision and the low limits of detection, in this study are very important because these elements are in concentrations between ppb and ppt. This technique allowed the analysis of the samples having a complex matrix by the presence CaCO_3 minimizing the interferences thanks to the ionization efficiency of the Ar plasma. For the species Pachychilus monachus were found concentrations of "2"3"2Th of 0.16-5.37 μg/g and of total U of 0.101-4.081 μg/g being this species where the highest values of total U were found. For Thiara (melanoids) tuberculata the lowest values were found among the different species ("2"3"2Th 0.61-3.61 μg/g and total U 0.006-0.042 μg/g), for Pachychilus suturalis, values of "2"3"2Th of 0.58-6.4 μg/g and for Pachychilus sp. were found between 0.26-7.62 μg/g and for total U values between 0.28-3.33 μg/g. The method offers several advantages: speed, good precision, low values of quantification limits and high sensitivity in the measurement of radio-nuclides and heavy metals. (Author)

Effect of lattice distortion on uranium magnetic moments in U4Ru7Ge6 studied by polarized neutron diffraction

Science.gov (United States)

Vališka, Michal; Klicpera, Milan; Doležal, Petr; Fabelo, Oscar; Stunault, Anne; Diviš, Martin; Sechovský, Vladimír

2018-03-01

In a cubic ferromagnet, small spontaneous lattice distortions are expected below the Curie temperature, but the phenomenon is usually neglected. This study focuses on such an effect in the U4Ru7Ge6 compound. Based on DFT calculations, we propose a lattice distortion from the cubic I m -3 m space group to a lower, rhombohedral, symmetry described by the R -3 m space group. The strong spin-orbit coupling of the uranium ions plays an essential role in lowering the symmetry, giving rise to two different U sites (U1 and U2). Using polarized neutron diffraction in applied magnetic fields of 1 and 9 T in the ordered state (1.9 K ) and in the paramagnetic state (20 K ), we bring convincing experimental evidence of this splitting of the U sites, with different magnetic moments. The data have been analyzed both by maximum entropy calculations and by a direct fit in the dipolar approximation. In the ordered phase, the μL/μS ratio of the orbital and spin moments on the U2 site is remarkably lower than for the free U3 + or U4 + ion, which points to a strong hybridization of the U 5 f wave functions with the 4 d wave functions of the surrounding Ru. On the U1 site, the μL/μS ratio exhibits an unexpectedly low value: the orbital moment is almost quenched, like in metallic α -uranium. As a further evidence of the 5 f -4 d hybridization in the U4Ru7Ge6 system, we observe the absence of a magnetic moment on the Ru1 site, but a rather large induced moment on the Ru2 site, which is in closer coordination with both U positions. Very similar results are obtained at 20 K in the ferromagnetic regime induced by the magnetic field of 9 T . This shows that applying a strong magnetic field above the Curie temperature also leads to the splitting of the uranium sites, which further demonstrates the intimate coupling of the magnetic ordering and structural distortion. We propose that the difference between the magnetic moment on the U1 and U2 sites results from the strong spin

Therapeutic efficacy of human hepatocyte transplantation in a SCID/uPA mouse model with inducible liver disease.

Directory of Open Access Journals (Sweden)

Donna N Douglas

2010-02-01

Full Text Available Severe Combined Immune Deficient (SCID/Urokinase-type Plasminogen Activator (uPA mice undergo liver failure and are useful hosts for the propagation of transplanted human hepatocytes (HH which must compete with recipient-derived hepatocytes for replacement of the diseased liver parenchyma. While partial replacement by HH has proven useful for studies with Hepatitis C virus, complete replacement of SCID/uPA mouse liver by HH has never been achieved and limits the broader application of these mice for other areas of biomedical research. The herpes simplex virus type-1 thymidine kinase (HSVtk/ganciclovir (GCV system is a powerful tool for cell-specific ablation in transgenic animals. The aim of this study was to selectively eliminate murine-derived parenchymal liver cells from humanized SCID/uPA mouse liver in order to achieve mice with completely humanized liver parenchyma. Thus, we reproduced the HSVtk (vTK/GCV system of hepatic failure in SCID/uPA mice.In vitro experiments demonstrated efficient killing of vTK expressing hepatoma cells after GCV treatment. For in vivo experiments, expression of vTK was targeted to the livers of FVB/N and SCID/uPA mice. Hepatic sensitivity to GCV was first established in FVB/N mice since these mice do not undergo liver failure inherent to SCID/uPA mice. Hepatic vTK expression was found to be an integral component of GCV-induced pathologic and biochemical alterations and caused death due to liver dysfunction in vTK transgenic FVB/N and non-transplanted SCID/uPA mice. In SCID/uPA mice with humanized liver, vTK/GCV caused death despite extensive replacement of the mouse liver parenchyma with HH (ranging from 32-87%. Surprisingly, vTK/GCV-dependent apoptosis and mitochondrial aberrations were also localized to bystander vTK-negative HH.Extensive replacement of mouse liver parenchyma by HH does not provide a secure therapeutic advantage against vTK/GCV-induced cytotoxicity targeted to residual mouse hepatocytes

Measurement of 233U/234U ratios in contaminated groundwater using alpha spectrometry

International Nuclear Information System (INIS)

Harrison, Jennifer J.; Payne, Timothy E.; Wilsher, Kerry L.; Thiruvoth, Sangeeth; Child, David P.; Johansen, Mathew P.; Hotchkis, Michael A.C.

2016-01-01

The uranium isotope 233 U is not usually observed in alpha spectra from environmental samples due to its low natural and fallout abundance. It may be present in samples from sites in the vicinity of nuclear operations such as reactors or fuel reprocessing facilities, radioactive waste disposal sites or sites affected by clandestine nuclear operations. On an alpha spectrum, the two most abundant alpha emissions of 233 U (4.784 MeV, 13.2%; and 4.824 MeV, 84.3%) will overlap with the 234 U doublet peak (4.722 MeV, 28.4%; and 4.775 MeV, 71.4%), if present, resulting in a combined 233+234 U multiplet. A technique for quantifying both 233 U and 234 U from alpha spectra was investigated. A series of groundwater samples were measured both by accelerator mass spectrometry (AMS) to determine 233 U/ 234 U atom and activity ratios and by alpha spectrometry in order to establish a reliable 233 U estimation technique using alpha spectra. The Genie™ 2000 Alpha Analysis and Interactive Peak Fitting (IPF) software packages were used and it was found that IPF with identification of three peaks ( 234 U minor, combined 234 U major and 233 U minor, and 233 U major) followed by interference correction on the combined peak and a weighted average activity calculation gave satisfactory agreement with the AMS data across the 233 U/ 234 U activity ratio range (0.1–20) and 233 U activity range (2–300 mBq) investigated. Correlation between the AMS 233 U and alpha spectrometry 233 U was r 2  = 0.996 (n = 10). - Highlights: • Describes a technique for deconvoluting the combined 233 U and 234 U multiplet in alpha spectra. • Enables 233 U and 234 U activities and 233 U/ 234 U ratios to be quantified without requiring additional analysis and measurement. • Applicable to an environmental matrix (groundwater) using standard alpha spectrometry counting equipment, operation and set-up.

ASM observations of X-ray flares from 4U 0115+63 and ASM 1354-64.

Science.gov (United States)

Tsunemi, H.; Kitamoto, S.

The authors report two X-ray flares detected with the All Sky Monitor (ASM) on board the GINGA satellite. One is from the recurrent X-ray pulsar 4U 0115+63 and the other is from the probable recurrent X-ray nova named ASM 1354-64. The maximum intensity for 4U 0115+63 was 180 mCrab and its duration was at least 22 days. Its spectrum was hard and resembled those of X-ray pulsars. The maximum intensity of ASM 1354-64 was 300 mCrab. It faded down below the detection limit at the end of August 1987. Its spectrum was soft and was similar to those of black hole candidates.

The High Energy X-ray Spectrum of 4U1700-37 Observed from OSO-8

Science.gov (United States)

Dolan, J. F.; Coe, M. J.; Crannell, C. J.; Dennis, B. R.; Frost, K. J.; Maurer, G. S.; Orwig, L. E.

1979-01-01

The most intense hard X-ray source in the confused region in Scorpius is identified as 4U1700-37. The 3.4-day modulation is seen above 20 keV with the intensity during eclipse being consistent with zero flux. The photon-number spectrum from 20 to 150 keV is well represented by a single power law with a photo-number spectral index of -2.77 + or - 0.35 or by a thermal bremsstrahlung spectrum with kT = 27 96.8-min X-ray modulation previously reported at lower energies. Despite the difficulties in reconciling both the lack of periodic modulation in the emitted X-radiation and the orbital dynamics of the system with theories of the evolution and physical properties of neutron stars, the observed properties of 4U1700-37 are all consistent with the source being a spherically accreting neutron star rather than a black hole.

Facile synthesis of magnetic Fe3O4/graphene composites for enhanced U(VI) sorption

Science.gov (United States)

Zhao, Donglin; Zhu, Hongyu; Wu, Changnian; Feng, Shaojie; Alsaedi, Ahmed; Hayat, Tasawar; Chen, Changlun

2018-06-01

A novel magnetic Fe3O4/graphene composite (FGC) was fabricated by a facile one-step reaction route and shown to be effective for sorbing U(VI) from aqueous solution. The structure, properties and application of the prepared FGC composite were well evaluated. The high saturation magnetization (45.6 emu/g) made FGC easier to be separated from the media within several seconds under an external magnetic. Effects of different ambient conditions (i.e., pH and ionic strength, contact time, temperatures) on sorption behaviors of U(VI) on FGC were carried out by batch experiments. According to the calculation of Langmuir model, the maximum sorption capacity of U(VI) on the FGC at pH 5.5 and 298 K was 176.47 mg/g. The sorption was correlated with the effects of pH, contact time, and temperature. X-ray photoelectron spectroscopy analysis revealed that U(VI) was sorbed on FGC via oxygen-containing functional groups. This work demonstrated that FGC could be recycled and used as an effective recyclable sorbent for sorption of U(VI).

Neutron capture cross-section measurements for 238U between 0.4 and 1.4 MeV

Science.gov (United States)

Krishichayan, Fnu; Finch, S. W.; Howell, C. R.; Tonchev, A. P.; Tornow, W.

2017-09-01

Neutron-induced radiative-capture cross-section data of 238U are crucial for fundamental nuclear physics as well as for Stewardship Science, for advanced-fuel-cycle calculations, and for nuclear astrophysics. Based on different techniques, there are a large number of 238U(n, γ) 239U cross-section data available in the literature. However, there is a lack of systematic and consistent measurements in the 0.1 to 3.0 MeV energy range. The goal of the neutron-capture project at TUNL is to provide accurate 238U(n, γ) 239U cross-section data in this energy range. The 238U samples, sandwiched between gold foils of the same size, were irradiated for 8-14 hours with monoenergetic neutrons. To avoid any contribution from thermal neutrons, the 238U and 197Au targets were placed inside of a thin-walled pill-box made of 238U. Finally, the whole pill-box was wrapped in a gold foil as well. After irradiation, the samples were gamma-counted at the TUNL's low-background counting facility using high-efficient HPGe detectors. The 197Au monitor foils were used to calculate the neutron flux. The experimental technique and 238U(n, γ) 239U cross-section results at 6 energies will be discussed during the meeting.

Modular metal chalcogenide chemistry: secondary building blocks as a basis of the silicate-type framework structure of CsLiU(PS_4)_2

International Nuclear Information System (INIS)

Neuhausen, Christine; Rocker, Frank; Tremel, Wolfgang

2012-01-01

The novel uranium thiophosphate CsLiU(PS_4)_2 has been synthesized by reacting uranium metal, Cs_2S, Li_2S, S, and P_2S_5 at 700 C in an evacuated silica tube. The crystal structure was determined by single-crystal X-ray diffraction techniques. CsLiU(PS_4)_2 crystallizes in the rhombohedral space group R anti 3c (a = 15.2797(7) Aa; c = 28.778(2) Aa, V = 5818.7(5) Aa"3, Z = 18). The structure of CsLiU(PS_4)_2 is a unique three-dimensional U(PS_4)_2"2"- framework with large tunnels with an approximate diameter of 6.6 Aa running parallel to the crystallographic c axis. The tunnels are filled with Cs"+ cations. The smaller Li"+ cations are located at tetrahedral sites at the periphery of the channels. In the structure of CsLiU(PS_4)_2 the uranium atoms are coordinated by thiophosphate groups in a pseudotetrahedral fashion, and the PS_4 groups act as linear connectors. Topologically, CsLiU(PS_4)_2 may be regarded a chalcogenide analogue of silicate frameworks, with the uranium atoms and PS_4 groups replacing silicon and oxygen atoms. Alternatively, CsLiU(PS_4)_2 may be viewed as a coordination polymer, which is formed in salt melts by the solid state equivalent of the ''self-assembly'' reactions in solution. Magnetic susceptibility measurements indicated Curie-Weiss-type behavior between 4 K and 300 K. The μ_e_f_f of 2.83 μ_B at 300 K is in agreement with an f"2 configuration of U"4"+. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

U(1) x U(1) x U(1) symmetry of the Kimura 3ST model and phylogenetic branching processes

International Nuclear Information System (INIS)

Bashford, J D; Jarvis, P D; Sumner, J G; Steel, M A

2004-01-01

An analysis of the Kimura 3ST model of DNA sequence evolution is given on the basis of its continuous Lie symmetries. The rate matrix commutes with a U(1) x U(1) x U(1) phase subgroup of the group GL(4) of 4 x 4 invertible complex matrices acting on a linear space spanned by the four nucleic acid base letters. The diagonal 'branching operator' representing speciation is defined, and shown to intertwine the U(1) x U(1) x U(1) action. Using the intertwining property, a general formula for the probability density on the leaves of a binary tree under the Kimura model is derived, which is shown to be equivalent to established phylogenetic spectral transform methods. (letter to the editor)

Transformation temperatures γU → δUZr2 Y γU →αU in U-Zr-Nb alloys

International Nuclear Information System (INIS)

Komar Varela, Carolina L.; Arico, Sergio F.; Gribaudo, Luis M.; Comision Nacional de Energia Atomica, General San Martin

2009-01-01

The international RERTR program has as primary objective the development of new fuels for research and test reactors to satisfy the requirement of low enrichment in 235 U (lower than 20 %). It is known that the cubic-phase (γU) has an excellent behaviour under irradiation. In this context, in the Materials Department (GIDAT-GAEN-CNEA) U-Zr-Nb alloys are considered candidates for the development of a high-density monolithic-type nuclear fuel. It is necessary to evaluate the thermodynamic parameters that allow to obtain a range of concentrations of the U-Zr-Nb system in which this phase can be retained in the metastable condition with the required 235 U density. In this work, eight U alloys with concentrations ranging from 13.9 to 43.7 wt.% Zr and from 0 to 6.4 wt.% Nb, were fabricated. Dynamical measurements of electrical resistivity, with a cooling rate of 4 o C/min, were performed and the results were analyzed. Considering this cooling rate, a Nb concentration of at least 17.8 wt. % would inhibit the transformation γU→ δUZr 2 and a concentration of al least 23.3 wt % would inhibit the γU → αU transformation. (author)

Suzaku Observations of 4U 1957+11: Potentially the Most Rapidly Spinning Black Hole in (the Halo of) the Galaxy

Science.gov (United States)

Nowak, Michael A.; Wilms, Joern; Pottschmidt, Katja; Schulz, Norbert; Maitra, Dipankar; Miller, Jon

2011-01-01

We present three Suzaku observations of the black hole candidate 4U 1957+11 (V 1408 Aql) - a source that exhibits some of. the simplest and cleanest examples of soft, disk-dominated spectra. 4U 1957+ II also presents among the. highest peak temperatures found from disk-dominated spectra. Such temperatures may be associated with rapid black hole spin. The 4U 1957+11 spectra also require a very low normalization, which can be explained by a combination of small inner disk radius and a large distance (> 10 kpc) which places 4U 1957+ 11 well into the Galactic halo. We perform Joint fits to the Suzaku spectra with both relativistic and Comptonized disk models. Assuming a low mass black hole and the nearest distance (3 Stellar Mass, 10 kpc), the dimensionless spin parameter a* = Jc/GM(sup 2)> or approx. 0.9. Higher masses and farther distances yield a* approx. = 1. Similar conclusions are reached with Comptonization models; they imply a combination of small inner disk radii (or, equivalently, rapid spin) and large distance. Low spin cannot be recovered unless 4U 1957+11 is a low mass black hole that is at the unusually large distance of > or approx.40 kpc. We speculate whether the suggested maximal spin is related to how the system came to reside in the halo.

Isothermal section of diagram of U-Mo-B and U-Re-B systems

International Nuclear Information System (INIS)

Val'ovka, I.P.; Kuz'ma, Yu.B.

1986-01-01

The methods of X-ray analysis are used to study the U-Mo-B and U-Re-B systems and to plot phase equilibrium diagrams at 1000 and 800 deg C, respectively. A formation of boride UMoB 4 (structure of the ThMoB 4 type) is confirmed in the U-Mo-B system and new compounds are found: U 2 MoB 6 (rhombic structure of the Y 2 ReB 6 type, a=0.9301(9), b=1.1434(11), c=0.3678(4) nm), ∼UMo 2 B 6 and ∼ UMo 4 B 4 with unknown structures. In the U-Re-B system besides previously known boride UReB 4 (the ThMoB 4 structure type), new ones are obtained: U 2 ReB 6 (Y 2 ReB 6 type, a=0.9373(9), b=1.1529(13), c0.3653(4) nm) and UReB 3 (hexagonal structure of the proper type, a=0.5083(1), c=0.5095(1) nm)

Investigation on the instability characteristics in MM-4U tandem mirror

International Nuclear Information System (INIS)

Ye Rubin; Ming Linzhou; Wu Guangun; Shi Qiang; Xu Liyun; Li Zhicai; Zhao Xiaochun

1995-06-01

The plasma fluctuation signals in MM-4U tandem mirror were investigated by using linear spectral analysis. Oscillation and propagation characteristics of the instability were obtained. the instability mode and probable exciting mechanism and a method for measuring electron temperature were deduced. The wave-wave nonlinear interaction processes were studied by using nonlinear spectral analysis technique. It is shown that the nonlinear three waves interaction process exists in the device as the main nonlinear process. The nonlinear interaction broadens the spectra of the instability

The 4U 0115+63: Another energetic gamma ray binary pulsar

Science.gov (United States)

Chadwick, P. M.; Dipper, N. A.; Dowthwaite, J. C.; Kirkman, I. W.; Mccomb, T. J. L.; Orford, K. J.; Turver, K. E.

1985-01-01

Following the discovery of Her X-1 as a source of pulsed 1000 Gev X-rays, a search for emission from an X-ray binary containing a pulsar with similar values of period, period derivative and luminosity was successful. The sporadic X-ray binary 4U 0115-63 has been observed, with probability 2.5 x 10 to the minus 6 power ergs/s to emit 1000 GeV gamma-rays with a time averaged energy flux of 6 to 10 to the 35th power.

A novel ternary uranium-based intermetallic U{sub 34}Fe{sub 4−x}Ge{sub 33}: Structure and physical properties

Energy Technology Data Exchange (ETDEWEB)

Henriques, M.S., E-mail: mish@itn.pt [Campus Tecnológico e Nuclear, Instituto Superior Técnico, Universidade de Lisboa, CFMC-UL, Estrada Nacional 10, 2695-066 Bobadela (Portugal); Berthebaud, D. [Institut des Sciences Chimiques de Rennes, Chimie du Solide et Matériaux, Université Rennes 1, UMR CNRS 6226, 263 Avenue du Général Leclerc, 35042 Rennes (France); CRISMAT, UMR CNRS 6508, 6 bd. Maréchal Juin, 14050 Caen (France); Waerenborgh, J.C.; Lopes, E.B. [Campus Tecnológico e Nuclear, Instituto Superior Técnico, Universidade de Lisboa, CFMC-UL, Estrada Nacional 10, 2695-066 Bobadela (Portugal); Pasturel, M.; Tougait, O. [Institut des Sciences Chimiques de Rennes, Chimie du Solide et Matériaux, Université Rennes 1, UMR CNRS 6226, 263 Avenue du Général Leclerc, 35042 Rennes (France); Gonçalves, A.P. [Campus Tecnológico e Nuclear, Instituto Superior Técnico, Universidade de Lisboa, CFMC-UL, Estrada Nacional 10, 2695-066 Bobadela (Portugal)

2014-09-01

Highlights: • A new uranium intermetallic compound U{sub 34}Fe{sub 4−x}ge{sub 33} was prepared and characterized. • It crystallizes in the tetragonal system with an original structure-type. • U lattice stacking is made of cupolae, orthobicupola and irregular cubes. • U{sub 34}Fe{sub 4−x}Ge{sub 33} orders magnetically at T{sub C} = 28 K, with pure U magnetism. • T{sub C} and electrical resistivity increase with applied magnetic field. - Abstract: The new ternary phase U{sub 34}Fe{sub 4−x}Ge{sub 33} has been synthesized and characterized by means of single crystal X-ray diffraction, magnetization, Mössbauer spectroscopy, specific heat, electrical resistivity, magnetoresistivity and thermopower measurements. It crystallizes in its own tetragonal structure type which can be described as derived from the one of the binary USi (U{sub 34}Si{sub 34.5} structure-type, space group I4/mmm), with lattice parameters at room temperature, a = 10.873(5) Å and c = 25.274(3) Å. Structure refinement confirmed six inequivalent U atoms, occupying sites with dissimilar coordination, the Ge atoms staying on seven positions and Fe on two positions, one of the Fe sites with a partial occupancy. The U sub-lattice is composed by the stacking of a square cupola, two distorted cubes and a square orthobicupola. U{sub 34}Fe{sub 4−x}Ge{sub 33} with x = 0.68 undergoes a ferromagnetic-type transition below 28 K. Mössbauer spectroscopy shows that the magnetism is ruled by the U sub-lattice, as Fe atoms have no ordered moments. The Sommerfeld coefficient of the electronic specific heat is γ = 131 mJ/(mol{sub U} K{sup 2}), whereas the estimated magnetic entropy at T{sub C} is 0.22Rln2. A residual resistivity of 314 μΩ cm and a resistivity ratio of 1.1 were found in the electrical resistivity curve, which also exhibits an upturn below T{sub C} that shifts towards higher temperatures with the applied magnetic field. This behavior may be related to some disorder in the non

A WHITE DWARF MERGER AS PROGENITOR OF THE ANOMALOUS X-RAY PULSAR 4U 0142+61?

International Nuclear Information System (INIS)

Rueda, J. A.; Boshkayev, K.; Izzo, L.; Ruffini, R.; Lorén-Aguilar, P.; Külebi, B.; Aznar-Siguán, G.; García-Berro, E.

2013-01-01

It has been recently proposed that massive, fast-rotating, highly magnetized white dwarfs could describe the observational properties of some of soft gamma-ray repeaters and anomalous X-ray pulsars (AXPs). Moreover, it has also been shown that high-field magnetic white dwarfs can be the outcome of white dwarf binary mergers. The products of these mergers consist of a hot central white dwarf surrounded by a rapidly rotating disk. Here we show that the merger of a double degenerate system can explain the characteristics of the peculiar AXP 4U 0142+61. This scenario accounts for the observed infrared excess. We also show that the observed properties of 4U 0142+6 are consistent with an approximately 1.2 M ☉ white dwarf, remnant of the coalescence of an original system made of two white dwarfs of masses 0.6 M ☉ and 1.0 M ☉ . Finally, we infer a post-merging age τ WD ≈ 64 kyr and a magnetic field B ≈ 2 × 10 8 G. Evidence for such a magnetic field may come from the possible detection of the electron cyclotron absorption feature observed between the B and V bands at ≈10 15 Hz in the spectrum of 4U 0142+61

4D display of the outflow track of embryonic-chick hearts (HH 14-19) using a high speed streak mode OCT

Science.gov (United States)

Ma, Siyu; Wang, Rui; Goodwin, Richard L.; Markwald, Roger R.; Borg, Thomas K.; Runyan, Raymond B.; Gao, Zhi

2013-02-01

Congenital Heart Disease (CHD) is the most common congenital malformation in newborns in the US. Although knowledge of CHD is limited, altered hemodynamic conditions are suspected as the factor that stimulates cardiovascular cell response, resulting in the heart morphology remodeling that ultimately causes CHDs. Therefore, one of recent efforts in CHD study is to develop high-speed imaging tools to correlate the rapidly changing hemodynamic condition and the morphological adaptations of an embryonic heart in vivo. We have developed a high-speed streak mode OCT that works at the center wavelength of 830 nm and is capable of providing images (292x220 μm2) of the outflow tract of an embryonic chick heart at the rate of 1000 Hz. The modality can provide a voxel resolution in the range of 10 μm3, and the spectral resolution allows a depth range of 1.63 mm. In the study reported here, each of the 4D images of an outflow tract was recorded for 2 seconds. The recording was conducted every 2 hours (HH17 to HH18), 3 hours (HH14 to HH17), and 4 hours (HH18 to HH19). Because of the fast scan speed, there is no need for postacquisition processing such as use of gating techniques to provide a fine 3D structure. In addition, more details of the outflow tract are preserved in the recorded images. The 4D images can be used in the future to determine the role of blood flow in CHD development.

Impact of pEGFP mediated ING4 gene on growth of glioma U251 ...

African Journals Online (AJOL)

Jane

2011-06-22

Jun 22, 2011 ... Full Length Research Paper. Impact of pEGFP mediated ING4 gene on growth of glioma U251 cells and its potential molecular mechanism. Yuefei Deng*, Bingxi Lei and Yiying Zhao. Department of Neurosurgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China.

Behavior of uranium along Jucar River (Eastern Spain). Determination of 234U/238U and 235U/238U ratios

International Nuclear Information System (INIS)

Rodriguez-Alvarez, M.J.; Sanchez, F.

1995-01-01

The uranium concentration and the 234 U/ 238 U, 235 U/ 238 U activity ratios were studied in water samples from Jucar River, using low-level α-spectrometry. The effects of pH, temperature and salinity were considered and more detailed sampling was done in the neighbourhood of Cofrentes Nuclear Plant (Valencia, Spain). Changes were observed in the uranium concentration with the salinity and the 234 U/ 238 U activity ratio was found to vary with pH. Leaching and dilution, which depend on pH and salinity, are the probable mechanisms for these changes in the concentration of uranium and the activity ratios. (author) 25 refs.; 4 figs.; 1 tab

THE FERMI-GBM X-RAY BURST MONITOR: THERMONUCLEAR BURSTS FROM 4U 0614+09

International Nuclear Information System (INIS)

Linares, M.; Chakrabarty, D.; Connaughton, V.; Bhat, P. N.; Briggs, M. S.; Preece, R.; Jenke, P.; Kouveliotou, C.; Wilson-Hodge, C. A.; Van der Horst, A. J.; Camero-Arranz, A.; Finger, M.; Paciesas, W. S.; Beklen, E.; Von Kienlin, A.

2012-01-01

Thermonuclear bursts from slowly accreting neutron stars (NSs) have proven difficult to detect, yet they are potential probes of the thermal properties of the NS interior. During the first year of a systematic all-sky search for X-ray bursts using the Gamma-ray Burst Monitor aboard the Fermi Gamma-ray Space Telescope we have detected 15 thermonuclear bursts from the NS low-mass X-ray binary 4U 0614+09 when it was accreting at nearly 1% of the Eddington limit. We measured an average burst recurrence time of 12 ± 3 days (68% confidence interval) between 2010 March and 2011 March, classified all bursts as normal duration bursts and placed a lower limit on the recurrence time of long/intermediate bursts of 62 days (95% confidence level). We discuss how observations of thermonuclear bursts in the hard X-ray band compare to pointed soft X-ray observations and quantify such bandpass effects on measurements of burst radiated energy and duration. We put our results for 4U 0614+09 in the context of other bursters and briefly discuss the constraints on ignition models. Interestingly, we find that the burst energies in 4U 0614+09 are on average between those of normal duration bursts and those measured in long/intermediate bursts. Such a continuous distribution in burst energy provides a new observational link between normal and long/intermediate bursts. We suggest that the apparent bimodal distribution that defined normal and long/intermediate duration bursts during the last decade could be due to an observational bias toward detecting only the longest and most energetic bursts from slowly accreting NSs.

Ultraboosted Zt and γt production at the HL-LHC and FCC-hh

Energy Technology Data Exchange (ETDEWEB)

Aguilar-Saavedra, J.A. [Universidad de Granada, Departamento de Fisica Teorica y del Cosmos, Granada (Spain)

2017-11-15

Searches for anomalous Zt and γt production provide an excellent probe of flavour-changing top interactions when the energies considered are very large. In this note we estimate the sensitivity to these interactions at the high-luminosity phase of the LHC and a future 100 TeV pp collider (FCC-hh). For the LHC, the expected limits on t → uZ/uγ branching ratios from Zt and γt production will reach the 10{sup -5} level, one order of magnitude better than the existing projections for t → uZ from t anti t production. For the FCC-hh, the limits on t → uZ/uγ could reach an impressive sensitivity at the 10{sup -6} level, with limits on t → cZ/cγ at the 10{sup -5} level. (orig.)

Comparison of measured and calculated 238U capture self-indication ratios from 4 to 10 keV

International Nuclear Information System (INIS)

Perez, R.B.; de Saussure, G.; Yang, J.T.; Munoz-Cobos, J.L.; Todd, J.H.

1983-01-01

From 4 keV to 149 keV the 238 U cross sections are represented in ENDF/B-V by unresolved-resonance parameters (URP). The purpose of this representation is to enable the calculation of resonance self-protection as a function of temperature and dilution. Since the URPs are not defined unambiguously by the cross-section data, it is important that the unresolved representation be tested with appropriate experiments, such as capture self-indication ratio (SIR) measurements. In this paper we compare 238 U capture SIR measurements in the 4- to 10-keV energy range with calculations done with ENDF/B-V and with recently published resolved resonance parameters

Alteration of RNA splicing by small molecule inhibitors of the interaction between NHP2L1 and U4

Science.gov (United States)

Diouf, Barthelemy; Lin, Wenwei; Goktug, Asli; Grace, Christy R. R.; Waddell, Michael Brett; Bao, Ju; Shao, Youming; Heath, Richard J.; Zheng, Jie J.; Shelat, Anang A.; Relling, Mary V.; Chen, Taosheng; Evans, William E.

2018-01-01

Splicing is an important eukaryotic mechanism for expanding the transcriptome and proteome, influencing a number of biological processes. Understanding its regulation and identifying small molecules that modulate this process remains a challenge. We developed an assay based on time-resolved FRET (TR-FRET) to detect the interaction between the protein NHP2L1 and U4 RNA, which are two key components of the spliceosome. We used this assay to identify small molecules that interfere with this interaction in a high-throughput screening (HTS) campaign. Topotecan and other camptothecin derivatives were among the top hits. We confirmed that topotecan disrupts the interaction between NHP2L1 and U4 by binding to U4 and inhibits RNA splicing. Our data reveal new functions of known drugs which could facilitate the development of therapeutic strategies to modify splicing and alter gene function. PMID:28985478

U enrichment and Th/U fractionation in Archean boninites: Implications for paleo-ocean oxygenation and U cycling at juvenile subduction zones

Science.gov (United States)

Manikyamba, C.; Said, Nuru; Santosh, M.; Saha, Abhishek; Ganguly, Sohini; Subramanyam, K. S. V.

2018-05-01

Phanerozoic boninites record enrichments of U over Th, giving Th/U: 0.5-1.6, relative to intraoceanic island arc tholeiites (IAT) where Th/U averages 2.6. Uranium enrichment is attributed to incorporation of shallow, oxidized fluids, U-rich but Th-poor, from the slab into the melt column of boninites which form in near-trench to forearc settings of suprasubduction zone ophiolites. Well preserved Archean komatiite-tholeiite, plume-derived, oceanic volcanic sequences have primary magmatic Th/U ratios of 4.4-3.6, and Archean convergent margin IAT volcanic sequences, having REE and HFSE compositions similar to Phanerozoic IAT equivalents, preserve primary Th/U of 4-3.6. The best preserved Archean boninites of the 3.0 Ga Olondo and 2.7 Ga Gadwal greenstone belts, hosted in convergent margin ophiolite sequences, also show relative enrichments of U over Th, with low average Th/U ∼3 relative to coeval IAT, and Phanerozoic counterparts which are devoid of crustal contamination and therefore erupted in an intraoceanic setting, with minimal contemporaneous submarine hydrothermal alteration. Later enrichment of U is unlikely as Th-U-Nb-LREE patterns are coherent in these boninites whereas secondary effects induce dispersion of Th/U ratios. The variation in Th/U ratios from Archean to Phanerozoic boninites of greenstone belts to ophiolitic sequences reflect on genesis of boninitic lavas at different tectono-thermal regimes. Consequently, if the explanation for U enrichment in Phanerozoic boninites also applies to Archean examples, the implication is that U was soluble in oxygenated Archean marine water up to 600 Ma before the proposed great oxygenation event (GOE) at ∼2.4 Ga. This interpretation is consistent with large Ce anomalies in some hydrothermally altered Archean volcanic sequences aged 3.0-2.7 Ga.

Overview of JT-60U results toward high integrated performance in reactor-relevant regime

International Nuclear Information System (INIS)

Fujita, T.

2002-01-01

Toward steady sustainment of high integrated performance, we have developed weak magnetic shear (high β p mode) and reversed magnetic shear plasmas. As a large-sized tokamak equipped with a variety of devices for heating, current drive and profile/shape control, JT-60U has high ability to approach the conditions required in reactors: low values of normalized Larmor radius and collisionality, high temperatures with T e > or approx. T i , etc. This paper reviews recent JT-60U results with the emphasis on the projection to the reactor-relevant regime. Full non-inductive current drive has been achieved in a 1.8 MA high β p H-mode plasma with β N 2:4, HH y2 =1.2 and high fusion triple product (3 x 10 20 m -3 keVs) owing to increased N-NB power. In a reversed shear plasma, HH y2 =1.4 at n e /n GW 0.8 under the full non-inductive current drive has been achieved with injection of LHRF and N-NB. In box-type ITBs with reversed shear, barriers for ions and electrons were sustained in a regime with T e > or approx. T i . The pedestal pressure was doubled with increased total poloidal beta in pellet-injected high triangularity plasmas with type I and II ELMs. Stable existence of current hole was demonstrated. (author)

Effect of Utilization of Silicide Fuel with the Density 4.8 gU/cc on the Kinetic Parameters of RSG-GAS Reactor

International Nuclear Information System (INIS)

Setiyanto; Sembiring, Tagor M.; Pinem, Surian

2007-01-01

Presently, the RSG-GAS reactor using silicide fuel element of 2.96 gU/cc. For increasing reactor operation time, its planning to change to higher density fuel. The kinetic calculation of silicide core with density 4.8 gU/cc has been carried out, since it has an influence on the reactor operation safety. The calculated kinetic parameters are the effective delayed neutron fraction, the delayed neutron decay constant, prompt neutron lifetime and feedback reactivity coefficient very important for reactor operation safety. the calculation is performed in 2-dimensional neutron diffusion-perturbation method using modified Batan-2DIFF code. The calculation showed that the effective delayed neutron fraction is 7. 03256x10 -03 , total delay neutron time constant is 7.85820x10 -02 s -1 and the prompt neutron lifetime is 55.4900 μs. The result of prompt neutron lifetime smaller 10 % compare with silicide fuel of 4.8 gU/cc. The calculated results showed that all of the feedback reactivity coefficient silicide core 4.8 gU/cc is negative. Totally, the feedback reactivity coefficient of silicide fuel of 4.8 gU/cc is 10% less than that of silicide fuel of 2.96 gU/cc. The results shown that kinetic parameters result decrease compared with the silicide core with density 2.96 gU/cc, but no significant influence in the RSG-GAS reactor operation. (author)

Einstein SSS and MPC observations of Aql X-1 and 4U1820-30

Science.gov (United States)

Kelley, R. L.; Christian, D. J.; Schoelkopf, R. J.; Swank, J. H.

1989-01-01

The results of timing and spectral analyses of the X-ray sources Aql X-1 (X1908+005) and 4U1820-30 (NGC6624) are reported using data obtained with the Einstein SSS (Solid State Spectrometer) and MPC (Monitor Proportional Counter) instruments. A classic type I burst was observed from Aql X-1 in both detectors and a coherent modulation with a period of 131.66 + or - 0.02 ms and a pulsed fraction of 10 percent was detected in the SSS data. There is no evidence for a loss of coherance during the approximately 80 sec when the burst is observable. The 2 sigma upper limit on the rate of change of the pulse period is 0.00005s/s. It is argued that an asymmetrical burst occurring on a neutron star rotating at 7.6 Hz offers a plausible explanation for the oscillation. The data from 4U1820-30 show that the amplitude of the 685 sec modulation, identified as the orbital period, is independent of energy down to 0.6 keV. The SSS data show that the light curve in the 0.6 to 4.5 keV band is smoother than at higher energies.

Quantum phase transition in the U(4) vibron model and the E(3) symmetry

International Nuclear Information System (INIS)

Zhang Yu; Hou Zhanfeng; Chen Huan; Wei Haiqing; Liu Yuxin

2008-01-01

We study the details of the U(3)-O(4) quantum phase transition in the U(4) vibron model. Both asymptotic analysis in the classical limit and rigorous calculations for finite boson number systems indicate that a second-order phase transition is still there even for the systems with boson number N ranging from tens to hundreds. Two kinds of effective order parameters, including E1 transition ratios B(E1:2 1 →1 1 )/B(E1:1 1 →0 1 ) and B(E1:0 2 →1 1 )/B(E1:1 1 →0 1 ), and the energy ratios E 2 1 /E 0 2 and E 3 1 /E 0 2 are proposed to identify the second-order phase transition in experiments. We also found that the critical point of phase transition can be approximately described by the E(3) symmetry, which persists even for moderate N∼10 protected by the scaling behaviors of quantities at the critical point. In addition, a possible empirical example exhibiting roughly the E(3) symmetry is discussed

Intake of 210Po, 234U and 238U radionuclides with beer in Poland

International Nuclear Information System (INIS)

Skwarzec, B.; Struminska, D.I.; Borylo, A.; Falandysz, J.

2004-01-01

238 U, 234 U and 210 Po activity concentrations were determined in beer in Poland by alpha-spectrometry with low-level activity silicon detectors. The results revealed that the mean concentrations of 238 U, 234 U and 210 Po in the analyzed beer samples were 4.63, 4.11 and 4.94 mBq x dm -3 , respectively, the highest in Tyskie (5.71 for 210 Po, 5.06 for 234 U and 6.11 for 238 U) and the lowest in Lech (2.49 for 210 Po). The effective radiation dose due to uranium and polonium ingestions by beer was calculated and were compared to the effective radiation dose from drinking water. (author)

The properties of cross-correlation and spectra of the low-mass X-ray binary 4U 1608-52

International Nuclear Information System (INIS)

Lei, Ya-Juan; Yuan, Hai-Long; Dong, Yi-Qiao; Zhang, Hao-Tong; Zhang, Cheng-Min; Zhao, Yong-Heng; Zhang, Shu; Qu, Jin-Lu; Wang, Ya-Nan; Li, Zhi-Bing

2014-01-01

With RXTE data, we analyzed the cross-correlation function between the soft and hard X-rays of the transient atoll source 4U 1608-52. We found anti-correlations in three outbursts occurred in 1998, 2002, and 2010, and we found significant time lags of several hundreds of seconds in the latter two outbursts. Our results show no correlation between the soft and hard X-rays in the extreme island state and a dominated positive correlation in the lower banana state. Anti-correlations are presented at the upper banana state for the outburst of 2010 and at the island and the lower left banana states for the other two outbursts. So far for atoll sources, the cross-correlation has been studied statistically only for 4U 1735-44, where anti-correlations showed up in the upper banana state. Here our investigation on 4U 1608-52 provides a similar result in its 2010 outburst. In addition, we notice that the luminosities in the upper banana of the 1998 and 2002 outbursts are about 1.5 times that of the 2010 outburst whose luminosity in the upper banana is close to that of 4U 1735-44. The results suggest that the states in the color-color diagram of a source could be correlated with the luminosity of the source. A further spectral analysis during the 2010 outburst is also shown, which suggests that the disk can be a little truncated in the upper banana. The feature on the upper banana is similar to the previous results of the flaring branch in Z sources.

XPS study of U, UNi5, UCu5 and UNisub(0.5)Cusub(4.5)

International Nuclear Information System (INIS)

Grohs, H.; Hoechst, H.; Steiner, P.; Huefner, S.; Buschow, K.H.J.

1980-01-01

Core and valence band spectra of U metal and the intermetallic compounds UNi 5 , UCu 5 and UNisub(0.5)Cusub(4.5) have been measured by X-ray excited photoelectron spectroscopy (XPS). The data indicate that in UNi 5 the configuration is 5f 3 , and in UCu 5 and UNisub(0.5)Cusub(4.5) a mixed valence configuration with fewer 5f electrons than in UNi 5 is present. (author)

RXTE Observation of 4U 1630-47 During its 1998 Outburst

Science.gov (United States)

Dieters, Stefan W.

1999-01-01

During the 1998 outburst of 4U 1630-47 it was extensively observed with the Rossi X-ray Timing Explorer (RXTE). In order to cover the outburst more thoroughly our data (Obs. ID: 30178-0[1-2]- ) were combined with those of Cui et al. (Obs. ID: 30188-02-). These observations were later compared with the complementary observations. Power density and energy spectra have been made for each observation. The data was used to place radio and hard X-ray observations within context. Analysis of SAX (Satellite per Astronomia a raggi X) and BATSE (Burst and Transient Source Experiment) data was also included within the study. The count rate and position in hardness-intensity, color-color diagrams and simple spectral fits are used to track the concurrent spectral changes. The source showed seven distinct types of timing behavior, most of which show differences with the canonical black hole spectral/timing states. In marked contrast to previous outbursts, we find quasi-periodic oscillation (QPO) signals during nearly all stages of the outburst with frequencies between 0.06 Hz and 14 Hz and a remarkable variety of other characteristics. In particular we find large (up to 23% rms) amplitude QPO on the early rise. Later, slow 0.1 Hz semi- regular short (- 5 sec), 9 to 16% deep dips dominate the light curve. At this time there are two QPOS, one stable near 13.5 Hz and the other whose frequency drops from 6-8 Hz to - 4.5 Hz during the dips. BeppoSAX observations during the very late declining phase show 4U 1630-47 in a low state. These results will shortly be published. We are completing a detailed analysis of the energy spectra (in preparation). The QPO/noise properties are being correlated with the concurrent spectral changes. Detailed studies of the QPO are being undertaken using sophisticated timing analysis methods. Finally a comparison with the other outbursts of 1630-47 is being made.

Studies of U(4) oxidation kinetics in nitric acid and TBP phases

International Nuclear Information System (INIS)

Taylor, R.J.; Denniss, I.S.; Koltunov, V.S.; Marchenko, V.I.; Dvoeglazov, K.N.; Savilova, O.A.; Broan, C.J.

2000-01-01

U(IV) is an important reagent in current reprocessing plants since it is used to reduce Pu(IV) to Pu(III), therefore, allowing the efficient separation of U and Pu in multi-stage counter-current solvent extraction contactors. The benefits of U(IV) are that it is a kinetically fast reductant and it is a salt free reagent, since U(IV) is oxidised to U(VI) and so does not add to the aqueous waste volumes. Many kinetic reactions of U(IV) have been studied in the past and these are used by BNFL to model the behaviour of U(IV) in process flowsheets. However, some reactions have either not been studied or have been studied many times without conclusive resolution. Therefore, to expand our understanding of U(IV) in the process and to generate data that underpins process models, we are studying a series of U(IV) reactions, and this paper will summarize the results of our kinetic and mechanistic studies. (authors)

IMPLICATIONS OF X-RAY LINE VARIATIONS FOR 4U1822-371

International Nuclear Information System (INIS)

Ji, L.; Schulz, N. S.; Nowak, M. A.; Canizares, C. R.

2011-01-01

4U 1822-371 is one of the prototype accretion disk coronal sources with an orbital period of about 5.6 hr. The binary is viewed almost edge-on at a high inclination angle of 83 deg., which makes it a unique candidate to study binary orbital and accretion disk dynamics in high powered X-ray sources. We observed the X-ray source in 4U 1822-371 with the Chandra High Energy Transmission Grating Spectrometer for almost nine binary orbits. X-ray eclipse times provide an update of the orbital ephemeris. We find that our result follows the quadratic function implied by previous observations; however, it suggests a flatter trend. From the orbital line dynamics, we confirm the previous suggestion that recombination emission is located at the impact bulge of the accretion stream. Our observations show that the recombining plasma is confined to this region, and prove that it has to be a very thin layer on top of the accretion disk. Fe XXVI emission is detected at all phases and likely originates from the hot central corona which has optical depth <<1. The implied ionization parameters from both regions strongly suggest that the illuminating source is obscured with respect to the observer and is orders of magnitude brighter than what is actually observed. This is independently confirmed by the best fit of a flat power law with a high-energy cutoff and partial covering absorption with a covering fraction of about 50%. We discuss the implications of our findings with respect to the photoionized line emission and the spectral continuum on basic properties of the X-ray source.

Numerical aspects of U-Mo core covered by Zry-4 miniplates co-rolling

International Nuclear Information System (INIS)

Picchetti, B.; Moscarda, M.V.; Taboada, H.

2013-01-01

The aim of this work is to support through adequate modeling the development of the co-rolling process of miniplates and plates starting with compacts including a monolithic U-Mo core with Zry-4 frame and cladding, Through relevant parameter identification and specific variables calculation a co rolling process model was set. The goal is to design a co-rolling optimal strategy related to the expected results through the use of such model. To that end the rolling process is depicted and some elements of strain stress theory on metals are employed. Plastic strain depends on deviator components of the stress tensor but no on the hydrostatic one. Metal sheet co-rolling is a plastic strain by planar compression at constant volume. During the co-rolling process the width constancy is assumed, being the piece of metal free to flow along its length. In this work the relationship between constitutive materials shield stresses U-Mo core and Zry-4 cladding under T= 650°C co-rolling is determined. This allows to modeling the reduction that exist in each co-rolling step for each one of phases present, which enables the design of a loop control lace optimizing the co rolling process. (author)

The high energy X-ray spectrum of 4U 1700-37 observed from OSO 8

Science.gov (United States)

Dolan, J. F.; Coe, M. J.; Crannell, C. J.; Dennis, B. R.; Frost, K. J.; Orwig, L. E.; Maurer, G. S.

1980-01-01

The most intense hard X-ray source in the confused region in Scorpius has been identified as 4U 1700-37 (=HD 153919). Observations extending over three binary periods in 1978 September were carried out with the high-energy X-ray spectrometer on OSO 8. The 3.4 day modulation is seen above 20 keV with the intensity during eclipse being consistent with zero flux. The photonumber spectrum from 20 to 150 keV is well represented by a single power law with a photonumber spectral index of -2.77 + or - 0.35 or by a thermal bremsstrahlung spectrum with kT = 27 (+15, -7)keV. The counting rate above 20 keV outside of eclipse shows no evidence for the 96.8 minute X-ray modulation previously reported at lower energies. Despite the difficulties that exist in reconciling both the lack of periodic modulation in the emitted X-radiation and the orbital dynamics of the system with our currently accepted theories of the evolution and physical properties of neutron stars, the observed properties of 4U 1700-37 are all consistent with the source being a spherically accreting neutron star rather than a black hole.

Splitting Fermi Surfaces and Heavy Electronic States in Non-Centrosymmetric U3Ni3Sn4

Science.gov (United States)

Maurya, Arvind; Harima, Hisatomo; Nakamura, Ai; Shimizu, Yusei; Homma, Yoshiya; Li, DeXin; Honda, Fuminori; Sato, Yoshiki J.; Aoki, Dai

2018-04-01

We report the single-crystal growth of the non-centrosymmetric paramagnet U3Ni3Sn4 by the Bridgman method and the Fermi surface properties detected by de Haas-van Alphen (dHvA) experiments. We have also investigated single-crystal U3Ni3Sn4 by single-crystal X-ray diffraction, magnetization, electrical resistivity, and heat capacity measurements. The angular dependence of the dHvA frequencies reveals many closed Fermi surfaces, which are nearly spherical in topology. The experimental results are in good agreement with local density approximation (LDA) band structure calculations based on the 5f-itinerant model. The band structure calculation predicts many Fermi surfaces, mostly with spherical shape, derived from 12 bands crossing the Fermi energy. To our knowledge, the splitting of Fermi surfaces due to the non-centrosymmetric crystal in 5f-electron systems is experimentally detected for the first time. The temperature dependence of the dHvA amplitude reveals a large cyclotron effective mass of up to 35 m0, indicating the heavy electronic state of U3Ni3Sn4 due to the proximity of the quantum critical point. From the field dependence of the dHvA amplitude, a mean free path of conduction electrons of up to 1950 Å is detected, reflecting the good quality of the grown crystal. The small splitting energy related to the antisymmetric spin-orbit interaction is most likely due to the large cyclotron effective mass.

U-Shaped Interest in U-Shaped Development--and What It Means

Science.gov (United States)

Siegler, Robert S.

2004-01-01

Interest in U-shaped development has itself undergone a U-shaped progression. Twenty-five years ago, interest in U-shaped development was high. This interest was evident at a 1978 conference in Tel Aviv on "U-shaped Behavioral Growth" that resulted in the publication of a book of the same title 4 years later (Strauss, 1982). The breadth…

Analysis of the 3 and 4 cycles with extensions in the operation of the CNLV U-1; Analisis de los ciclos 3 y 4 con extensiones en la operacion de la CNLV U-1

Energy Technology Data Exchange (ETDEWEB)

Montes T, J.L.; Torres A, C.; Perusquia C, R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

1992-08-15

The objective of the report is the comparison of the radial distributions of burned in the core among the results of the simulation of the Laguna Verde Central U-1 reactor during the operation of the cycles 1 to 4 and the data of the operation with information provided by the fuel supplier. (Author)

Drying results of K-Basin fuel element 5744U (Run 4)

International Nuclear Information System (INIS)

Klinger, G.S.; Oliver, B.M.; Abrefah, J.; Marschman, S.C.; MacFarlan, P.J.; Ritter, G.A.

1998-07-01

The water-filled K-Basins in the Hanford 100 Area have been used to store N-Reactor spent nuclear fuel (SNF) since the 1970s. Because some leaks in the basins have been detected and some of the fuel is breached due to handling damage and corrosion, efforts are underway to remove the fuel elements from wet storage. An Integrated Process Strategy (IPS) has been developed to package, dry, transport, and store these metallic uranium fuel elements in an interim storage facility on the Hanford Site. Information required to support the development of the drying processes, and the required safety analyses, is being obtained from characterization tests conducted on fuel elements removed from the K-Basins. A series of whole element drying tests (reported in separate documents, see Section 8.0) have been conducted by Pacific Northwest National Laboratory (PNNL) on several intact and damaged fuel elements recovered from both the K-East and K-West Basins. This report documents the results of the fourth of those tests, which was conducted on an N-Reactor outer fuel element removed from K-West canister 5744U. This element (referred to as Element 5744U) was stored underwater in the K-West Basin from 1983 until 1996. Element 5744U was subjected to a combination of low- and high-temperature vacuum drying treatments that were intended to mimic, wherever possible, the fuel treatment strategies of the IPS. The system used for the drying test was the Whole Element Furnace Testing System, described in Section 2.0, located in the Postirradiation Testing Laboratory (PTL, 327 Building). The test conditions and methodologies are given in Section 3.0. Inspections of the fuel element before and after the test are provided in Section 4.0. The experimental results are provided in Section 5.0, and discussed in Section 6.0

Preliminary results in double cusp tandem mirror MM-4U

International Nuclear Information System (INIS)

Ming Linzhou; Tian Zhongyu; Feng Xiaozhen

1990-10-01

MM-4U device and preliminary experimental results are presented. Main results are as follows: The plasma has been produced by means of the injection of strong electron current; the axial profile of the plasma potential and the plasma electron density have been obtained respectively, they had a simular form; the plasma potential in the centre of the east cusp, the west cusp and the simple mirror; V e = -180V, V w = -164V, V m -1.8V; the electron density: n e = 1.7 x 10 11 cm -3 , n w = 4.7 x 10 10 cm -3 , n m = 7.5 x 10 7 cm -3 ; the electron temperature: T e = (19.9 ± 1.6) eV, T w = (20.7 ± 1.7) eV; the plasma pressure at 8 cm on the right of the west cusp centre is about 6.76 Pa, β ≅ 1.7 x 10 -3 . The plasma instability has been observed in the simple mirror, its vibration frequency was 7∼9.2 kHz. The results are discussed. The next new task of the physical experiment are proposed

U Shrinivasa

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education. U Shrinivasa. Articles written in Resonance – Journal of Science Education. Volume 17 Issue 4 April 2012 pp 365-377 General Article. The Evolution of Diesel Engines · U Shrinivasa · More Details Fulltext PDF ...

Hyperpolarized [U-(2) H, U-(13) C]Glucose reports on glycolytic and pentose phosphate pathway activity in EL4 tumors and glycolytic activity in yeast cells.

Science.gov (United States)

Timm, Kerstin N; Hartl, Johannes; Keller, Markus A; Hu, De-En; Kettunen, Mikko I; Rodrigues, Tiago B; Ralser, Markus; Brindle, Kevin M

2015-12-01

A resonance at ∼181 ppm in the (13) C spectra of tumors injected with hyperpolarized [U-(2) H, U-(13) C]glucose was assigned to 6-phosphogluconate (6PG), as in previous studies in yeast, whereas in breast cancer cells in vitro this resonance was assigned to 3-phosphoglycerate (3PG). These peak assignments were investigated here using measurements of 6PG and 3PG (13) C-labeling using liquid chromatography tandem mass spectrometry (LC-MS/MS) METHODS: Tumor-bearing mice were injected with (13) C6 glucose and the (13) C-labeled and total 6PG and 3PG concentrations measured. (13) C MR spectra of glucose-6-phosphate dehydrogenase deficient (zwf1Δ) and wild-type yeast were acquired following addition of hyperpolarized [U-(2) H, U-(13) C]glucose and again (13) C-labeled and total 6PG and 3PG were measured by LC-MS/MS RESULTS: Tumor (13) C-6PG was more abundant than (13) C-2PG/3PG and the resonance at ∼181 ppm matched more closely that of 6PG. (13) C MR spectra of wild-type and zwf1Δ yeast cells showed a resonance at ∼181 ppm after labeling with hyperpolarized [U-(2) H, U-(13) C]glucose, however, there was no 6PG in zwf1Δ cells. In the wild-type cells 3PG was approximately four-fold more abundant than 6PG CONCLUSION: The resonance at ∼181 ppm in (13) C MR spectra following injection of hyperpolarized [U-(2) H, U-(13) C]glucose originates predominantly from 6PG in EL4 tumors and 3PG in yeast cells. © 2014 Wiley Periodicals, Inc.

Evolution of the 1984 outburst of the transient X-ray source 4U 1630 - 47

International Nuclear Information System (INIS)

Parmar, A.N.; Stella, L.; White, N.E.

1986-01-01

The results of a series of EXOSAT observations of the X-ray transient 4U 1630 - 47 during an outburst in 1984 are presented. The source decayed over an interval of about 100 days from a maximum 1-50 keV luminosity of about 2.8 x 10 to the 38th to about 4 x 10 to the 36th erg/s (for an assumed distance of 10 kpc). The 1-50 keV spectrum was best represented by a soft Wien-like spectrum with a temperature about 1 keV and a high-energy power-law tail. The relative contribution of the soft component to that of the high-energy power law decreased by atleast a factor of about 2 as the overall luminosity decreased. When the source was at its maximum observed luminosity, short time scale 7 percent intensity variations (1-7 keV) were seen with a characteristic time scale of about 20 s. The shortest time scale variability detected was about 50 ms. A 10-arcsec position obtained using an imaging telescope excludes a previously suggested optical counterpart. The spectral properties of 4U 1630 - 47 are reminiscent of those of the black hole candidate Cyg X-1 when it evolves from a high to a low state. 28 references

Study of the initial oxidation of the U4Zr2Nb alloy by X-ray photoelectron spectroscopy

International Nuclear Information System (INIS)

Mendonca, Renato de; Ferraz, Wilmar B.; Braga, Daniel M.; Macedo, Waldemar A.A.

2009-01-01

In this work, the initial stages of oxidation of the U4Zr2Nb alloy in O 2 atmosphere were studied in-situ, in ultrahigh vacuum, by X-ray photoelectron spectroscopy (XPS), an advanced surface-sensitive technique. After several hours of Ar + ion-sputtering to surface cleanness, the O 2 exposures was realized on the sample at room temperature. The evolution of oxide film formed on the sample surface was followed by XPS measures, by using Mg K α radiation of 1253.6 eV and a CLAM-2 (Vacuum Generator) electron energy analyzer. The changes of U 4f, Nb 3d, Zr 3d and O 1s photoemission peaks with O 2 exposure indicate that the adsorption of oxygen on the U4Zr2Nb alloy surface leads to fast formation of UO 2 . The alloying elements show slower oxidation and different compounds are observed in Nb 3d spectra analysis. This work shows an expressive enlargement of Nb 3d peak at 100 Langmuir exposure, indicating the formation of Nb 2 O 5 and NbO in the oxide. On the other hand, the binding energy of Zr 3d suggests that the ZrO 2 formation is stable as well as uranium dioxide. (author)

The disc-jet coupling in the neutron star X-ray binary 4U 1728-34

NARCIS (Netherlands)

Tudose, Valeriu; Tzioumis, Anastasios; Belloni, Tomaso; Altamirano, Diego; Linares, Manuel; Mendez, Mariano; Hiemstra, Beike

2010-01-01

The present radio proposal is part of a multi-wavelength campaign focused on the study of the accretion/ejection process in the neutron star X-ray binary system 4U 1728-34. Our intention is to study the behaviour of the inner part of the accretion disc as inferred from the X-ray observations of the

Informacioni sistemi u upravljanju rizicima u životnoj sredini

Directory of Open Access Journals (Sweden)

Dejan Inđić

2013-02-01

Full Text Available Normal 0 MicrosoftInternetExplorer4 Sažetak: Zemljotresi, poplave, nuklearni i hemijski akcidenti, zagađivanje vazduha, zemljišta i voda, ukazuju na sve veće prisustvo nesreća nastalih intenzivnim razvojem i često nekontrolisanom primenom tehnološkog razvoja. Pred društvo se postavlja problem kako se što bolje pripremiti, kako obezbediti veću usklađenost i funkcionisanje aktivnosti i mera za sprečavanje nastanka akcidentnih situacija i kako uneti promene u društveni i tehnološki razvoj koje će ići u korist prirode, ali i za dobrobit budućih generacija. U radu je prikazano korišćenje različitih informacionih sistema (IS u upravljanju rizicima u životnoj sredini i predlog za izradu jedinstvenog IS u Republici Srbiji.

The U phase formation in cement-based systems containing high amounts of Na2SO4

International Nuclear Information System (INIS)

Li, G.; Moranville, M.; Le Bescop, P.

1996-01-01

Simulated cemented low level wastes containing high amounts of Na 2 SO 4 (10--15%) were examined with respect to the mineralogy of the solid phases, chemical composition of the interstitial aqueous phase and immersion behavior in water. All results reveal the formation of a mineral called U phase, first observed by Dosch and zur Strassen in 1967, and its deleterious effects on the samples immersed in water. It appears that this phase can form only at very high alkaline concentration, not compatible with traditional cement paste. Two possible degradation mechanisms associated with the U phase are proposed which are to be elucidated in further works

Quantitative dissolution of (U, Pu)O2 MOX (0.4% to 44% PuO2) using microwave heating technique

International Nuclear Information System (INIS)

Malav, R.K.; Fulzele, Ajit K.; Prakash, Amrit; Afzal, Md.; Panakkal, J.P.

2011-01-01

AFFF has fabricated the (U, Pu)O 2 mixed oxide fuels for PHWRs, BWRs, PFBRs and FBTRs. The quantitative dissolution of the fuel samples are required within time for accurate determination of uranium-plutonium in chemical quality control laboratory. This paper describes the use of microwave heating technique in quantitative dissolution of (U, Pu)O 2 MOX (from 0.4% to 44% PuO 2 ). (author)

Solid state reactions of MoO3 and Na2MoO4 with (U.85,Ce.15)O2x

International Nuclear Information System (INIS)

Dahale, N.D.; Keskar, Meera; Singh Mudher, K.D.; Chawla, K.L.

1999-01-01

(U .85 ,Ce .15 )MoO 6-x was prepared by the solid state reactions of (U .85 ,Ce .15 )O 2±x with MoO 3 in air at 600 deg C. Solid state reactions of Na 2 MoO 4 with (U .85 ,Ce .15 )MoO 6.x up to 550 deg C in air led to the formation of Na 2 (U .85 ,Ce .15 )Mo 2 O 10-x and Na 2 (U .85 , Ce .15 ) 2 Mo 3 O 16-x . These compounds were characterised by x-ray and thermal methods. The x-ray powder data of (U .85 , Ce .15 ) MoO 6-x were indexed on monoclinic system whereas, data of Na 2 (U .85 ,Ce .15 ) Mo 2 O 10-x and Na 2 (U .85 ,Ce .15 ) 2 Mo 3 O 16-x were indexed on orthorhombic and monoclinic system respectively. (author)

Evolution of Spin, Orbital, and Superorbital Modulations of 4U 0114+650

International Nuclear Information System (INIS)

Hu, Chin-Ping; Ng, C.-Y.; Chou, Yi; Lin, Lupin Chun-Che; Yen, David Chien-Chang

2017-01-01

We report a systematic analysis of the spin, orbital, and superorbital modulations of 4U 0114+650, a high-mass X-ray binary that consists of one of the slowest spinning neutron stars. Using the dynamic power spectrum, we found that the spin period varied dramatically and is anticorrelated with the long-term X-ray flux variation that can be observed using the Rossi X-ray Timing Explorer ASM, Swift BAT, and the Monitor of All-sky X-ray Image. The spin-up rate over the entire data set is consistent with previously reported values; however, the local spin-up rate is considerably higher. The corresponding local spin-up timescale is comparable to the local spin-up rate of OAO 1657−415, indicating that 4U 0114+650 could also have a transient disk. Moreover, the spin period evolution shows two ∼1000-day spin-down/random-walk epochs that appeared together with depressions of the superorbital modulation amplitude. This implies that the superorbital modulation was closely related to the presence of the accretion disk, which is not favored in the spin-down/random-walk epochs because the accretion is dominated by the direct wind accretion. The orbital period is stable during the entire time span; however, the orbital profile significantly changes with time. We found that the depth of the dip near the inferior conjunction of the companion is highly variable, which disfavors the eclipsing scenario. Moreover, the dip was less obvious during the spin-down/random-walk epochs, indicating its correlation with the accretion disk. Further monitoring in both X-ray and optical bands could reveal the establishment of the accretion disk in this system.

Evolution of Spin, Orbital, and Superorbital Modulations of 4U 0114+650

Science.gov (United States)

Hu, Chin-Ping; Chou, Yi; Ng, C.-Y.; Lin, Lupin Chun-Che; Yen, David Chien-Chang

2017-07-01

We report a systematic analysis of the spin, orbital, and superorbital modulations of 4U 0114+650, a high-mass X-ray binary that consists of one of the slowest spinning neutron stars. Using the dynamic power spectrum, we found that the spin period varied dramatically and is anticorrelated with the long-term X-ray flux variation that can be observed using the Rossi X-ray Timing Explorer ASM, Swift BAT, and the Monitor of All-sky X-ray Image. The spin-up rate over the entire data set is consistent with previously reported values; however, the local spin-up rate is considerably higher. The corresponding local spin-up timescale is comparable to the local spin-up rate of OAO 1657-415, indicating that 4U 0114+650 could also have a transient disk. Moreover, the spin period evolution shows two ˜1000-day spin-down/random-walk epochs that appeared together with depressions of the superorbital modulation amplitude. This implies that the superorbital modulation was closely related to the presence of the accretion disk, which is not favored in the spin-down/random-walk epochs because the accretion is dominated by the direct wind accretion. The orbital period is stable during the entire time span; however, the orbital profile significantly changes with time. We found that the depth of the dip near the inferior conjunction of the companion is highly variable, which disfavors the eclipsing scenario. Moreover, the dip was less obvious during the spin-down/random-walk epochs, indicating its correlation with the accretion disk. Further monitoring in both X-ray and optical bands could reveal the establishment of the accretion disk in this system.

Evolution of Spin, Orbital, and Superorbital Modulations of 4U 0114+650

Energy Technology Data Exchange (ETDEWEB)

Hu, Chin-Ping; Ng, C.-Y. [Department of Physics, The University of Hong Kong, Pokfulam Road (Hong Kong); Chou, Yi [Graduate Institute of Astronomy, National Central University, Jhongli 32001, Taiwan (China); Lin, Lupin Chun-Che [Institute of Astronomy and Astrophysics, Academia Sinica, Taiwan (China); Yen, David Chien-Chang, E-mail: cphu@hku.hk [Department of Mathematics, Fu Jen Catholic University, New Taipei City 24205, Taiwan (China)

2017-07-20

We report a systematic analysis of the spin, orbital, and superorbital modulations of 4U 0114+650, a high-mass X-ray binary that consists of one of the slowest spinning neutron stars. Using the dynamic power spectrum, we found that the spin period varied dramatically and is anticorrelated with the long-term X-ray flux variation that can be observed using the Rossi X-ray Timing Explorer ASM, Swift BAT, and the Monitor of All-sky X-ray Image. The spin-up rate over the entire data set is consistent with previously reported values; however, the local spin-up rate is considerably higher. The corresponding local spin-up timescale is comparable to the local spin-up rate of OAO 1657−415, indicating that 4U 0114+650 could also have a transient disk. Moreover, the spin period evolution shows two ∼1000-day spin-down/random-walk epochs that appeared together with depressions of the superorbital modulation amplitude. This implies that the superorbital modulation was closely related to the presence of the accretion disk, which is not favored in the spin-down/random-walk epochs because the accretion is dominated by the direct wind accretion. The orbital period is stable during the entire time span; however, the orbital profile significantly changes with time. We found that the depth of the dip near the inferior conjunction of the companion is highly variable, which disfavors the eclipsing scenario. Moreover, the dip was less obvious during the spin-down/random-walk epochs, indicating its correlation with the accretion disk. Further monitoring in both X-ray and optical bands could reveal the establishment of the accretion disk in this system.

The subcritical mass limit, 2.4 kgU, for the JCO's precipitation tank

International Nuclear Information System (INIS)

Komuro, Yuichi

1999-01-01

The critical safety on the precipitation tank in JCO Corporation forming a critical accident in September 30, 1999 had to be guaranteed by limiting amount of uranium contained into charging solution. The limited value of uranic mass in the precipitation tank was determined to be 2.4 kg, and from the dissolution tank positioned at upstream of this tank a solution not excess amount of solution to this value was designed to be transferred. In the 2nd Accident Survey Committee, there were found some discussions on a leading method of this value. In order to answer some requirements for this, here was described on outlines on U.S. Nuclear Safety Guide, TID-7016 Rev. 1, leading method of the limited value in 2.4 kg, and safety tolerance. As a result of reinvestigation, as it was confirmed that 2.4 kg in the limited amount contained an sufficient safety tolerance qualitatively and in comparison with already critical data. (G.K.)

INTEGRAL/JEM-X reports enhanced activity from the HMXB 4U 1036-56

DEFF Research Database (Denmark)

Chenevez, Jérôme; Fiocchi, M.; Bazzano, A.

2015-01-01

During the Galactic Plane Scanning performed by INTEGRAL on December 11th, 2015, the X-ray monitor JEM-X has detected enhanced activity from the high mass X-ray binary (HMXB) 4U 1036-56, aka RX J1037.5-5647. The position of the source was covered by the JEM-X field of view two times between UTC 6...... 1036-56 is a Be X-ray pulsar (e.g. Torres et al. 2012, ApJ 761, 49), whose last outburst was reported by Swift in February 2012 (Krimm et al. ATel #3936)....

Black Hole Mass Determination In the X-Ray Binary 4U 1630-47: Scaling of Spectral and Variability Characteristics

Science.gov (United States)

Seifina, Elena; Titarchuk, Lev; Shaposhnikov, Nikolai

2014-01-01

We present the results of a comprehensive investigation on the evolution of spectral and timing properties of the Galactic black hole candidate 4U 1630-47 during its spectral transitions. In particular, we show how a scaling of the correlation of the photon index of the Comptonized spectral component gamma with low-frequency quasi-periodic oscillations (QPOs), ?(sub L), and mass accretion rate, M, can be applied to the black hole mass and the inclination angle estimates.We analyze the transition episodes observed with the Rossi X-Ray Timing Explorer and BeppoSAX satellites.We find that the broadband X-ray energy spectra of 4U 1630-47 during all spectral states can be modeled by a combination of a thermal component, a Comptonized component, and a red-skewed iron-line component. We also establish that gamma monotonically increases during transition from the low-hard state to the high-soft state and then saturates for high mass accretion rates. The index saturation levels vary for different transition episodes. Correlations of gamma versus ?(sub L) also show saturation at gamma (is) approximately 3. Gamma -M and gamma -?(sub L) correlations with their index saturation revealed in 4U 1630-47 are similar to those established in a number of other black hole candidates and can be considered as an observational evidence for the presence of a black hole in these sources. The scaling technique, which relies on XTE J1550-564, GRO 1655-40, and H1743-322 as reference sources, allows us to evaluate a black hole mass in 4U 1630-47 yielding M(sub BH) (is) approximately 10 +/- 0.1 solar masses and to constrain the inclination angle of i (is) approximately less than 70 deg.

Planning the Future of U.S. Particle Physics (Snowmass 2013): Chapter 4: Cosmic Frontier

Energy Technology Data Exchange (ETDEWEB)

Feng, J. L. [MIT, LNS; Ritz, S. [UC, Santa Cruz; Beatty, J. J. [Ohio State U.; Buckley, J. [Washington U., Seattle; Cowen, D. F. [Penn State U.; Cushman, P. [Minnesota U.; Dodelson, S. [Chicago U., Astron. Astrophys. Ctr.; Galbiati, C. [PNPI, CSTD; Honscheid, K. [Ohio State U.; Hooper, D. [Chicago U., Astron. Astrophys. Ctr.; Kaplinghat, M. [UC, Irvine; Kusenko, A. [Unlisted; Matchev, K. [Florida U.; McKinsey, D. [Yale U.; Nelson, A. E. [Washington U., Seattle; Olinto, A. [Chicago U., EFI; Profumo, S. [UC, Santa Cruz; Robertson, H. [Washington U., Seattle; Rosenberg, L. [Unlisted; Sinnis, G. [Los Alamos; Tait, T. M.P. [UCLA

2014-01-23

These reports present the results of the 2013 Community Summer Study of the APS Division of Particles and Fields ("Snowmass 2013") on the future program of particle physics in the U.S. Chapter 4, on the Cosmic Frontier, discusses the program of research relevant to cosmology and the early universe. This area includes the study of dark matter and the search for its particle nature, the study of dark energy and inflation, and cosmic probes of fundamental symmetries.

Determination of co-metabolism for 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT) degradation with enzymes from Trametes versicolor U97.

Science.gov (United States)

Sari, Ajeng Arum; Tachibana, Sanro; Itoh, Kazutaka

2012-08-01

Trametes versicolor U97 isolated from nature degraded 73% of the 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT) in a malt extract liquid medium after a 40-d incubation period. This paper presents a kinetic study of microbial growth using the Monod equation. T. versicolor U97 degraded DDT during an exponential growth phase, using glucose as a carbon source for growth. The growth of T. versicolor U97 was not affected by DDT. DDT was degraded by T. versicolor U97 only when the secondary metabolism coincided with the production of several enzymes. Furthermore, modeling of several inhibitors using the partial least squares function in Minitab 15, revealed lignin peroxidase (98.7 U/l) plays a role in the degradation of DDT. T. versicolor U97 produced several metabolites included a single-ring aromatic compound, 4-chlorobenzoic acid. Copyright © 2012 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Verification of LOCA/ECCS analysis codes ALARM-B2 and THYDE-B1 by comparison with RELAP4/MOD6/U4/J3

International Nuclear Information System (INIS)

Shimizu, Takashi

1982-08-01

For a verification study of ALARM-B2 code and THYDE-B1 code which are the component of the JAERI code system for evaluation of BWR ECCS performance, calculations for typical small and large break LOCA in BWR were done, and compared with those by RELAP4/MOD6/U4/J3 code. This report describes the influences of differences between the analytical models incorporated in the individual code and the problems identified by this verification study. (author)

Spectral State Evolution of 4U 1820-30: the Stability of the Spectral Index of Comptonization Tail

Science.gov (United States)

Titarchuk, Lev G.; Seifina, Elena; Frontera, Filippo

2013-01-01

We analyze the X-ray spectra and their timing properties of the compact Xray binary 4U 1820-30. We establish spectral transitions in this source seen with BeppoSAX and the Rossi X-ray Timing Explorer (RXTE). During the RXTE observations (1996 - 2009), the source were approximately approximately 75% of its time in the soft state making the lower banana and upper banana transitions combined with long-term low-high state transitions. We reveal that all of the X-ray spectra of 4U 1820-30 are fit by a composition of a thermal (blackbody) component, a Comptonization component (COMPTB) and a Gaussian-line component. Thus using this spectral analysis we find that the photon power-law index Gamma of the Comptonization component is almost unchangeable (Gamma approximately 2) while the electron temperature kTe changes from 2.9 to 21 keV during these spectral events. We also establish that for these spectral events the normalization of COMPTB component (which is proportional to mass accretion rate ?M) increases by factor 8 when kTe decreases from 21 keV to 2.9 keV. Before this index stability effect was also found analyzing X-ray data for Z-source GX 340+0 and for atolls, 4U 1728-34, GX 3+1. Thus, we can suggest that this spectral stability property is a spectral signature of an accreting neutron star source. On the other hand in a black hole binary G monotonically increases with ?Mand ultimately its value saturates at large ?M.

F{sub 4}U production by electrolytic reduction; Obtencion de UF{sub 4} por reduccion electrolitica

Energy Technology Data Exchange (ETDEWEB)

Esteban Duque, A; Gispert Benach, M; Hernandez Arroyo, F; Montes Ponce de Leon, M.; Rojas de Diego, J L

1974-07-01

As a part of the nuclear fuel cycle program developed at the Spanish Atomic Energy Commission it has been studied the electrolytic reduction of U-VI to U-IV. The effect of the materials, electrolyte concentration, pH, current density, cell size and laboratory scale production is studied. The Pilot Plant and the production data are also described. (Author) 18 refs.

Kinetic study of the thermal decomposition of uranium metaphosphate, U(PO{sub 3}){sub 4}, into uranium pyrophosphate, UP{sub 2}O{sub 7}

Energy Technology Data Exchange (ETDEWEB)

Yang, Hee-Chul, E-mail: nhcyang@kaeri.re.kr; Kim, Hyung-Ju; Lee, Si-Young; Yang, In-Hwan; Chung, Dong-Yong

2017-06-15

The thermochemical properties of uranium compounds have attracted much interest in relation to thermochemical treatments and the safe disposal of radioactive waste bearing uranium compounds. The characteristics of the thermal decomposition of uranium metaphosphate, U(PO{sub 3}){sub 4}, into uranium pyrophosphate, UP{sub 2}O{sub 7}, have been studied from the view point of reaction kinetics and acting mechanisms. A mixture of U(PO{sub 3}){sub 4} and UP{sub 2}O{sub 7} was prepared from the pyrolysis residue of uranium-bearing spent TBP. A kinetic analysis of the reaction of U(PO{sub 3}){sub 4} into UP{sub 2}O{sub 7} was conducted using an isoconversional method and a master plot method on the basis of data from a non-isothermal thermogravimetric analysis. The thermal decomposition of U(PO{sub 3}){sub 4} into UP{sub 2}O{sub 7} followed a single-step reaction with an activation energy of 175.29 ± 1.58 kJ mol{sup −1}. The most probable kinetic model was determined as a type of nucleation and nuclei-growth models, the Avrami-Erofeev model (A3), which describes that there are certain restrictions on nuclei growth of UP{sub 2}O{sub 7} during the solid-state decomposition of U(PO{sub 3}){sub 4}. - Highlights: •Thermal decomposition kinetics of U(PO{sub 3}){sub 4} into UP{sub 2}O{sub 7} was investigated. •The thermal decomposition followed a single-step reaction with an activation energy of 175.3 ± 1.6 kJ mol{sup −1}. •The most probable kinetic model was determined as a type of nucleation and nuclei-growth models, the Avrami-Erofeev (A3).

SO4--SO3- radical pair formation in Ce doped and Ce, U co-doped K3Na(SO4)2: EPR evidence and its role in TSL

International Nuclear Information System (INIS)

Natarajan, V.; Seshagiri, T.K.; Kadam, R.M.; Sastry, M.D.

2002-01-01

Thermally stimulated luminescence (TSL) and electron paramagnetic resonance (EPR) studies were carried out on cerium doped and cerium-uranium co-doped K 3 Na(SO 4 ) 2 samples after γ-irradiation. Three glow peaks around 352, 415 and 475 K were observed and their spectral characteristics have shown that Ce 3+ and UO 2 2+ act as the emission centres in K 3 Na(SO 4 ) 2 :Ce and K 3 Na(SO 4 ) 2 :Ce, U, respectively. In Ce-U co-doped sample, energy transfer from cerium to uranium takes place. The commonly occurring radiation-induced centres in sulphates, viz SO 3 - and SO 4 - were observed by EPR and SO 4 - radical ion was found to take part in the TSL emission at 415 K. The hitherto unknown information, however, is the formation of SO 4 - -SO 3 - radical pair creating deep traps in these lattices, apparently assisted by the dopants. This is the first observation of such radical pair formation leading to the identification of deep traps in this lattice. The radical pair, (SO 3 - -SO 4 - ) which is stable up to 970 K, decreases the intensity of the peak at 415 K due to the depletion of SO 4 - centres

Low Mass X-ray Binary 4U1705-44 Exiting an Extended High X-ray State

Science.gov (United States)

Phillipson, Rebecca; Boyd, Patricia T.; Smale, Alan P.

2017-09-01

The neutron-star low-mass X-ray binary 4U1705-44, which exhibited high amplitude long-term X-ray variability on the order of hundreds of days during the 16-year continuous monitoring by the RXTE ASM (1995-2012), entered an anomalously long high state in July 2012 as observed by MAXI (2009-present).

A long-term observation of 4U 1700-37 by the granat/watch all-sky monitor

DEFF Research Database (Denmark)

Sazonov, S.; Lapshov, I.; Sunyaev, R.

1995-01-01

with the help of Monte-Carlo simulations and derive the basic parameters of the stellar wind. We show that the wind in 4U 1700-37 well fits in the radiatively driven stellar wind theory. Our measurement of the mid-eclipse time together with the measurements of other experiments imply a decrease in the period...

A gravimetric and an X-ray fluorescence method for the determination of rubidium in Rb2U(SO4)3

International Nuclear Information System (INIS)

Mudher, K.D.S.; Krishnan, K.; Jayadevan, N.C.

1993-01-01

Chemical characterization of rubidium uranium(IV) trisulfate, RB 2 U(SO 4 ) 3 , a new chemical assay standard for uranium requires accurate analysis of rubidium. A gravimetric and an X-ray fluorescence method (XRF) for the determination of rubidium in this compound are described. In the gravimetric method, rubidium is determined as Rb 2 Na[Co(NO 2 ) 6 ].H 2 O without separating uranium with a precision of the order of ±0.5%. In the XRF method, the concentration ratio of rubidium to uranium, C Rb /C U , is determined in the solid samples by the binary ratio method using calibration between intensity ratios (I Rb /I U ) and concentration ratios (C Rb /C U ). (author) 6 refs.; 2 figs.; 3 tabs

Analysis of the right-handed Majorana neutrino mass in an S U (4 )×S U (2 )L×S U (2 )R Pati-Salam model with democratic texture

Science.gov (United States)

Yang, Masaki J. S.

2017-03-01

In this paper, we attempt to build a unified model with the democratic texture, that has some unification between up-type Yukawa interactions Yν and Yu . Since the S3 L×S3 R flavor symmetry is chiral, the unified gauge group is assumed to be Pati-Salam type S U (4 )c×S U (2 )L×S U (2 )R. The breaking scheme of the flavor symmetry is considered to be S3 L×S3 R→S2 L×S2 R→0 . In this picture, the four-zero texture is desirable for realistic masses and mixings. This texture is realized by a specific representation for the second breaking of the S3 L×S3 R flavor symmetry. Assuming only renormalizable Yukawa interactions, type-I seesaw mechanism, and neglecting C P phases for simplicity, the right-handed neutrino mass matrix MR can be reconstructed from low energy input values. Numerical analysis shows that the texture of MR basically behaves like the "waterfall texture." Since MR tends to be the "cascade texture" in the democratic texture approach, a model with type-I seesaw and up-type Yukawa unification Yν≃Yu basically requires fine-tunings between parameters. Therefore, it seems to be more realistic to consider universal waterfall textures for both Yf and MR, e.g., by the radiative mass generation or the Froggatt-Nielsen mechanism. Moreover, analysis of eigenvalues shows that the lightest mass eigenvalue MR 1 is too light to achieve successful thermal leptogenesis. Although the resonant leptogenesis might be possible, it also requires fine-tunings of parameters.

A delayed transition to the hard state for 4U 1630-47 at the end of its 2010 outburst

Energy Technology Data Exchange (ETDEWEB)

Tomsick, John A. [Space Sciences Laboratory, 7 Gauss Way, University of California, Berkeley, CA 94720-7450 (United States); Yamaoka, Kazutaka [Solar-Terrestrial Environment Laboratory, Department of Particles and Astronomy, Nagoya University, Furocho, Chikusa-ku, Nagoya, Aichi 464-8601 (Japan); Corbel, Stephane [AIM - Unité Mixte de Recherche CEA - CNRS - Université Paris VII - UMR 7158, CEA-Saclay, Service d' Astrophysique, F-91191 Gif-sur-Yvette Cedex (France); Kalemci, Emrah [Sabanci University, Orhanli-Tuzla, Istanbul 34956 (Turkey); Migliari, Simone [Department d' Astronomia i Meteorologia, Universitat de Barcelona, Marti I Franques 1, E-08028 Barcelona (Spain); Kaaret, Philip, E-mail: jtomsick@ssl.berkeley.edu [Department of Physics and Astronomy, University of Iowa, Van Allen Hall, Iowa City, IA 52242 (United States)

2014-08-10

Here we report on Swift and Suzaku observations near the end of an outburst from the black hole transient 4U 1630-47 and Chandra observations when the source was in quiescence. 4U 1630-47 made a transition from a soft state to the hard state ∼50 days after the main outburst ended. During this unusual delay, the flux continued to drop, and one Swift measurement found the source with a soft spectrum at a 2-10 keV luminosity of L = 1.07 × 10{sup 35} erg s{sup –1} for an estimated distance of 10 kpc. While such transients usually make a transition to the hard state at L/L{sub Edd} = 0.3%-3%, where L{sub Edd} is the Eddington luminosity, the 4U 1630-47 spectrum remained soft at L/L{sub Edd} = 0.008 M{sub 10}{sup −1}% (as measured in the 2-10 keV band), where M{sub 10} is the mass of the black hole in units of 10 M{sub ☉}. An estimate of the luminosity in the broader 0.5-200 keV bandpass gives L/L{sub Edd} = 0.03 M{sub 10}{sup −1}%, which is still an order of magnitude lower than typical. We also measured an exponential decay of the X-ray flux in the hard state with an e-folding time of 3.39 ± 0.06 days, which is much less than previous measurements of 12-15 days during decays by 4U 1630-47 in the soft state. With the ∼100 ks Suzaku observation, we do not see evidence for a reflection component, and the 90% confidence limits on the equivalent width of a narrow iron Kα emission line are <40 eV for a narrow line and <100 eV for a line of any width, which is consistent with a change of geometry (either a truncated accretion disk or a change in the location of the hard X-ray source) in the hard state. Finally, we report a 0.5-8 keV luminosity upper limit of <2 × 10{sup 32} erg s{sup –1} in quiescence, which is the lowest value measured for 4U 1630-47 to date.

Preparation of U-Si/U-Me (Me = Fe, Ni, Mn) aluminum-dispersion plate-type fuel (miniplates) for capsule irradiation

International Nuclear Information System (INIS)

Ugajin, Mitsuhiro; Itoh, Akinori; Akabori, Mitsuo

1993-06-01

Details of equipment installed, method adopted and final products were described on the preparation of uranium silicides and other fuels for capsule irradiation. Main emphasis was placed on the preparation of laboratory-scale aluminum-dispersion plate-type fuel (miniplates) loaded to the first and second JMTR silicide capsules. Fuels contained in the capsules are as follows: (A) uranium-silicide base alloys U 3 Si 2 , Mo- added U 3 Si 2 , U 3 Si 2 +U 3 Si, U 3 Si 2 +USi, U 3 Si, U 3 (Si 0.8 Ge 0.2 ), U 3 (Si 0.6 Ge 0.4 ) (B) U 6 Me-type alloys with higher uranium density U 6 Mn, U 6 Ni, U 6 (Fe 0.4 Ni 0.6 ), U 6 (Fe 0.6 Mn 0.4 ) The powder-metallurgical picture-frame method was adopted and laboratory-scale technique was established for the preparation of miniplates. As a result of inspection for capsule irradiation, miniplates were prepared to meet the requirements of specification. (author)

238U, 234U and 232Th in seawater

International Nuclear Information System (INIS)

Chen, J.H.; Edwards, R.L.; Wasserburg, G.J.

1986-01-01

We have developed techniques to determine 238 U, 234 U and 232 Th concentrations in seawater by isotope dilution mass spectrometry. Using these techniques, we have measured 238 U, 234 U and 232 Th in vertical profiles of unfiltered, acidified seawater from the Atlantic and 238 U and 234 U in vertical profiles from the Pacific. Determinations of 234 U/ 238 U at depths ranging from 0 to 4900 m in the Atlantic (7 0 44'N, 40 0 43'W) and the Pacific (14 0 41'N, 160 0 01'W) Oceans are the same within experimental error (±5per mille, 2σ). The average of these 234 U/ 238 U measurements is 144±2per mille (2σ) higher than the equilibrium ratio of 5.472 x 10 -5 . U concentrations, normalized to 35per mille salinity, range from 3.162 to 3.281 ng/g, a range of 3.8%. The average concentration of the Pacific samples (31 0 4'N, 159 0 1'W) is ∝1% higher than that of the Atlantic (7 0 44'N, 40 0 43'W and 31 0 49'N, 64 0 6'W). 232 Th concentrations from an Atlantic profile range from 0.092 to 0.145 pg/g. The observed constancy of the 234 U/ 238 U ratio is consistent with the predicted range of 234 U/ 238 U using a simple two-box model and the residence time of deep water in the ocean determined from 14 C. The variation in salinity-normalized U concentrations suggests that U may be much more reactive in the marine environment than previously thought. (orig./WB)

How Universal Are Free Will Beliefs? Cultural Differences in Chinese and U.S. 4- and 6-Year-Olds.

Science.gov (United States)

Wente, Adrienne O; Bridgers, Sophie; Zhao, Xin; Seiver, Elizabeth; Zhu, Liqi; Gopnik, Alison

2016-05-01

This study explores the development of free will beliefs across cultures. Sixty-seven Chinese 4- and 6-year-olds were asked questions to gauge whether they believed that people could freely choose to inhibit or act against their desires. Responses were compared to those given by the U.S. children in Kushnir, Gopnik, Chernyak, Seiver, and Wellman (). Results indicate that children from both cultures increased the amount of choice they ascribed with age. For inhibition questions, Chinese children ascribed less choice than the U.S. children. Qualitative explanations revealed that the U.S. children were also more likely to endorse notions of autonomous choice. These findings suggest both cultural differences and similarities in free will beliefs. © 2016 The Authors. Child Development © 2016 Society for Research in Child Development, Inc.

Dissolution behaviour of 238U, 234U and 230Th deposited on filters from personal dosemeters

International Nuclear Information System (INIS)

Beckova, V.; Malatova, I.

2008-01-01

Kinetics of dissolution of 238 U, 234 U and 230 Th dust deposited on filters from personal alpha dosemeters was studied by means of a 26-d in vitro dissolution test with a serum ultra-filtrate simulant. Dosemeters had been used by miners at the uranium mine 'Dolni Rozinka' at Rozna, Czech Republic. The sampling flow-rate as declared by the producer is 4 l h -1 and the sampling period is typically 1 month. Studied filters contained 125 ± 6 mBq 238 U in equilibrium with 234 U and 230 Th; no 232 Th series nuclides were found. Half-time of rapid dissolution of 1.4 d for 238 U and 234 U and slow dissolution half-times of 173 and 116 d were found for 238 U and 234 U, respectively. No detectable dissolution of 230 Th was found. (authors)

Effects of testing and storage environments on mechanical properties of Ni-plated and bare U-3/4 wt% Ti

International Nuclear Information System (INIS)

Zehr, S.W.; Johnson, H.R.; Smugeresky, J.E.; Pashman, K.A.; Nagelberg, A.S.

1980-01-01

It was found that storage environments with an adequate supply of oxygen can effectively minimize moisture corrosion of bare U-3/4 Ti. In particular, 0.75 cm 3 of dry air is calculated to protect 1 cm 2 of U-3/4 Ti for 20 years storage at room temperature. Consideration of the geometric details of U-3/4 Ti alloy specimens and the free volumes of air (and hence O 2 ) available can satisfactorily explain discrepancies in corrosion behavior between recent tests and previously reported data. The storage environment at 70 0 C produces a minor strength increase in bare samples with increasing time. Decreases in ductility are observed for testing conditions of low temperature, low strain rate, and/or high humidity. Surface cracks occur under the same conditions conducive to corrosion, i.e., moderate temperatures, low strain rates, and high humidity. Significant increases in strength result under low-temperature and high-strain-rate conditions of tensile testing. Residual chloride contamination may be responsible for the occasional and otherwise unexplained large scatter in ductility for nominally similar specimens and test conditions. Nickel plating is observed to cause a statistically significant decrease in tensile strength, but no effect on the yield strength or ductility was observed and the presence of high explosive during the aging of tensile bars was observed to have no effect on mechanical properties

Dissolution behaviour of 238U, 234U and 230Th deposited on filters from personal dosemeters.

Science.gov (United States)

Becková, Vera; Malátová, Irena

2008-01-01

Kinetics of dissolution of (238)U, (234)U and (230)Th dust deposited on filters from personal alpha dosemeters was studied by means of a 26-d in vitro dissolution test with a serum ultrafiltrate simulant. Dosemeters had been used by miners at the uranium mine 'Dolní Rozínka' at Rozná, Czech Republic. The sampling flow-rate as declared by the producer is 4 l h(-1) and the sampling period is typically 1 month. Studied filters contained 125 +/- 6 mBq (238)U in equilibrium with (234)U and (230)Th; no (232)Th series nuclides were found. Half-time of rapid dissolution of 1.4 d for (238)U and (234)U and slow dissolution half-times of 173 and 116 d were found for (238)U and (234)U, respectively. No detectable dissolution of (230)Th was found.

Comparison of the reactivity of 2-Li-C{sub 6}H{sub 4}CH{sub 2}NMe{sub 2} with MCl{sub 4} (M=Th, U). Isolation of a thorium aryl complex or a uranium benzyne complex

Energy Technology Data Exchange (ETDEWEB)

Seaman, Lani A.; Pedrick, Elizabeth A.; Wu, Guang; Hayton, Trevor W. [California Univ., Santa Barbara, CA (United States). Dept. of Chemistry and Biochemistry; Tsuchiya, Takashi; Jakubikova, Elena [North Carolina State Univ., Raleigh, NC (United States). Dept. of Chemistry

2013-09-27

Individualism under actinoids: The reaction of 2-Li-C{sub 6}H{sub 4}CH{sub 2}NMe{sub 2} with [MCl{sub 4} (dme) {sub n}] (M=Th, n=2; M=U, n=0) gives the thorium aryl complex [Th(2-C{sub 6}H{sub 4}CH{sub 2}NMe{sub 2}){sub 4}] or the uranium benzene complex Li[U(2,3-C{sub 6}H{sub 3}CH{sub 2}NMe{sub 2})(2-C{sub 6}H{sub 4}CH{sub 2}NMe{sub 2}){sub 3}]. A DFT analysis suggests that the formation of a benzyne complex with uranium but not with thorium is a kinetic and not thermodynamic effect. [German] Individualismus unter Actinoiden: Die Reaktion von 2-Li-C{sub 6}H{sub 4}CH{sub 2}NMe{sub 2} mit [MCl{sub 4} (dme) {sub n}] (M=Th, n=2; M=U, n=0) ergibt den Thoriumarylkomplex [Th(2-C{sub 6}H{sub 4}CH{sub 2}NMe{sub 2}){sub 4}] bzw. den Uranbenz-inkomplex Li[U(2,3-C{sub 6}H{sub 3}CH{sub 2}NMe{sub 2})(2-C{sub 6}H{sub 4}CH{sub 2}NMe{sub 2}){sub 3}]. Einer dichtefunktionaltheoretischen Analyse zufolge ist es kinetisch und nicht thermodynamisch bedingt, dass der Benz-inkomplex im Fall von Uran entsteht, nicht aber im Fall von Thorium.

The recruitment of the U5 snRNP to nascent transcripts requires internal loop 1 of U5 snRNA.

Science.gov (United States)

Kim, Rebecca; Paschedag, Joshua; Novikova, Natalya; Bellini, Michel

2012-12-01

In this study, we take advantage of the high spatial resolution offered by the nucleus and lampbrush chromosomes of the amphibian oocyte to investigate the mechanisms that regulate the intranuclear trafficking of the U5 snRNP and its recruitment to nascent transcripts. We monitor the fate of newly assembled fluorescent U5 snRNP in Xenopus oocytes depleted of U4 and/or U6 snRNAs and demonstrate that the U4/U6.U5 tri-snRNP is not required for the association of U5 snRNP with Cajal bodies, splicing speckles, and nascent transcripts. In addition, using a mutational analysis, we show that a non-functional U5 snRNP can associate with nascent transcripts, and we further characterize internal loop structure 1 of U5 snRNA as a critical element for licensing U5 snRNP to target both nascent transcripts and splicing speckles. Collectively, our data support the model where the recruitment of snRNPs onto pre-mRNAs is independent of spliceosome assembly and suggest that U5 snRNP may promote the association of the U4/U6.U5 tri-snRNP with nascent transcripts.

39 CFR 4.4 - Deputy Postmaster General.

Science.gov (United States)

2010-07-01

... 39 Postal Service 1 2010-07-01 2010-07-01 false Deputy Postmaster General. 4.4 Section 4.4 Postal... described at 39 U.S.C. 202(d), 203. The Deputy Postmaster General shall act as Postmaster General during the.... The Governors set the compensation and benefits of the Deputy Postmaster General, subject to 39 U.S.C...

Theoretical investigation of the Omega(g,u)(+/-) states of K2 dissociating adiabatically up to K(4p 2P(3/2)) + K(4p 2P(3/2)).

Science.gov (United States)

Jraij, A; Allouche, A R; Magnier, S; Aubert-Frécon, M

2009-06-28

A theoretical investigation of the electronic structure of the K(2) molecule, including spin-orbit effects, has been performed. Potential energies have been calculated over a large range of R up to 75a(0) for the 88 Omega(g,u)(+/-) states dissociating adiabatically into the limits up to K(4p (2)P(3/2))+K(4p (2)P(3/2)). Equilibrium distances, transition energies, harmonic frequencies, as well as depths for wells and heights for barriers are reported for all of the bound Omega(g,u)(+/-) states. Present ab initio calculations are shown to be able to reproduce quite accurately the small structures (wells and barrier) displayed at very long-range (R>50a(0)) by the (2,3)1(u) and (2)0(g)(-) purely long-range states. As the present data could help experimentalists, we make available extensive tables of energy values versus internuclear distances in our database at the web address http://www-lasim.univ-lyon1.fr/spip.php?rubrique99.

Interdiffusion between U(Mo,Pt) or U(Mo,Zr) and Al or Al A356 alloy

International Nuclear Information System (INIS)

Komar Varela, C.; Mirandou, M.; Arico, S.; Balart, S.; Gribaudo, L.

2009-01-01

Solid state reactions in chemical diffusion couples U-7 wt.%Mo-0.9 wt.%Pt/Al at 580 deg. C and U-7 wt.%Mo-0.9 wt.%Pt/Al A356 alloy, U-7 wt.%Mo-1 wt.%Zr/Al and U-7 wt.%Mo-1 wt.%Zr/Al A356 alloy at 550 deg. C were characterized. Results were obtained from optical and scanning electron microscopy, electron probe microanalysis and X-ray diffraction. The UAl 3, UAl 4 and Al 20 Mo 2 U phases were identified in the interaction layers of γU(Mo,Pt)/Al and γU(Mo,Zr)/Al diffusion couples. Al 43 Mo 4 U 6 ternary compound was also identified in γU(Mo,Zr)/Al due to the decomposition of γU(Mo,Zr) phase. The U(Al,Si) 3 and U 3 Si 5 phases were identified in the interaction layers of γU(Mo,Pt)/Al A356 and γU(Mo,Zr)/Al A356 diffusion couples. These phases are formed due to the migration of Si to the interaction layer. In the diffusion couple U(Mo,Zr)/Al A356, Zr 5 Al 3 phase was also identified in the interaction layer. The use of synchrotron radiation at Brazilian Synchrotron Light Laboratory (LNLS, CNPq, Campinas, Brazil) was necessary to achieve a complete crystallographic characterization.

(232)Th(d,4n)(230)Pa cross-section measurements at ARRONAX facility for the production of (230)U.

Science.gov (United States)

Duchemin, C; Guertin, A; Haddad, F; Michel, N; Métivier, V

2014-05-01

(226)Th (T1/2=31 min) is a promising therapeutic radionuclide since results, published in 2009, showed that it induces leukemia cells death and activates apoptosis pathways with higher efficiencies than (213)Bi. (226)Th can be obtained via the (230)U α decay. This study focuses on the (230)U production using the (232)Th(d,4n)(230)Pa(β-)(230)U reaction. Experimental cross sections for deuteron-induced reactions on (232)Th were measured from 30 down to 19 MeV using the stacked-foil technique with beams provided by the ARRONAX cyclotron. After irradiation, all foils (targets as well as monitors) were measured using a high-purity germanium detector. Our new (230)Pa cross-section values, as well as those of (232)Pa and (233)Pa contaminants created during the irradiation, were compared with previous measurements and with results given by the TALYS code. Experimentally, same trends were observed with slight differences in orders of magnitude mainly due to the nuclear data change. Improvements are ongoing about the TALYS code to better reproduce the data for deuteron-induced reactions on (232)Th. Using our cross-section data points from the (232)Th(d,4n)(230)Pa reaction, we have calculated the thick-target yield of (230)U, in Bq/μA·h. This value allows now to a full comparison between the different production routes, showing that the proton routes must be preferred. Copyright © 2014 Elsevier Inc. All rights reserved.

The fission cross sections of 230Th, 232Th, 233U, 234U, 236U, 238U, 237Np, 239Pu and 242Pu relative 235U at 14.74 MeV neutron energy

International Nuclear Information System (INIS)

Meadows, J.W.

1986-12-01

The measurement of the fission cross section ratios of nine isotopes relative to 235 U at an average neutron energy of 14.74 MeV is described with particular attention to the determination of corrections and to sources of error. The results are compared to ENDF/B-V and to other measurements of the past decade. The ratio of the neutron induced fission cross section for these isotopes to the fission cross section for 235 U are: 230 Th - 0.290 +- 1.9%; 232 Th - 0.191 +- 1.9%; 233 U - 1.132 +- 0.7%; 234 U - 0.998 +- 1.0%; 236 U - 0.791 +- 1.1%; 238 U - 0.587 +- 1.1%; 237 Np - 1.060 +- 1.4%; 239 Pu - 1.152 +- 1.1%; 242 Pu - 0.967 +- 1.0%. 40 refs., 11 tabs., 9 figs

The X-ray spectra of the black hole candidate 4U 1630-47 during its 2012 outburst

NARCIS (Netherlands)

Wang, Y.; Mendez, M.

2015-01-01

Diaz Trigo et al. (2013) reported the detection of three Doppler-shifted emission lines arising from baryonic matter in the jet of 4U 1630-47 during its 2012 outburst. Here we propose an alternative model that, without the need of the lines from the jet, and with less free parameters, fits the same

Spectral states evolution of 4U 1728-34 observed by INTEGRAL and RXTE: non-thermal component detection

NARCIS (Netherlands)

Tarana, A.; Belloni, T.; Bazzano, A.; Mendez, M.; Ubertini, P.

We report results of a one-year monitoring of the low-mass X-ray binary (LMXB) source (atoll type) 4U 1728-34 with INTEGRAL and RXTE. Three time intervals were covered by INTEGRAL, during which the source showed strong spectral evolution. We studied the broad-band X-ray spectra in detail by fitting

Analysis of the 3 and 4 cycles with extensions in the operation of the CNLV U-1

International Nuclear Information System (INIS)

Montes T, J.L.; Torres A, C.; Perusquia C, R.

1992-08-01

The objective of the report is the comparison of the radial distributions of burned in the core among the results of the simulation of the Laguna Verde Central U-1 reactor during the operation of the cycles 1 to 4 and the data of the operation with information provided by the fuel supplier. (Author)

Trimethylsilylcyclopentadienyl (cp{sup '}) uranium chemistry. Synthetic and structural studies of Cp{sup '}{sub 4}U and Cp{sup '}{sub 3}UX (X = Cl, I, Me)

Energy Technology Data Exchange (ETDEWEB)

Windorff, Cory J.; MacDonald, Matthew R.; Ziller, Joseph W.; Evans, William J. [Department of Chemistry, University of California, Irvine, CA (United States)

2017-12-13

Cp{sup '}{sub 4}U (Cp{sup '} = C{sub 5}H{sub 4}SiMe{sub 3}) was synthesized from: (a) KCp{sup '} and [Cp{sup '}{sub 3}U(THF)][BPh{sub 4}]; (b) Cp{sup '}{sub 3}U and Cp{sup '}{sub 2}Pb; and (c) [K(2.2.2-cryptand)][Cp{sup '}{sub 4}U] and AgBPh{sub 4}. The compound was identified by X-ray crystallography as a rare example of a structurally-characterized tetrakis(cyclopentadienyl)U{sup IV} complex. For comparison, the corresponding Th complex, Cp{sup '}{sub 4}Th, was isolated from the direct combination of ThBr{sub 4}(THF){sub 4} with excess KCp{sup '}. During the preparation of Cp{sup '}{sub 3}UMe, the precursor of the [Cp{sup '}{sub 3}U(THF)][BPh{sub 4}] reagent used above, it was discovered that the reaction of Cp{sup '}{sub 3}UCl and MeLi gives a mixture of Cp{sup '}{sub 3}UMe and Cp{sup '}{sub 3}UCl that can co-crystallize better than Cp{sup '}{sub 3}UMe in pure form. The Cp'{sub 3}UMe/Cp{sup '}{sub 3}UCl mixture forms single crystals suitable for X-ray crystallography and provides a new way to characterize the oil, Cp{sup '}{sub 3}UMe. Cp{sup '}{sub 3}UCl and Cp{sup '}{sub 3}UI were also crystallographically characterized for comparison with the Cp{sup '}{sub 3}UMe/Cp{sup '}{sub 3}UCl crystals. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Tank 241-U-102, Grab Samples 2U-99-1, 2U-99-2 and 2U-99-3 Analytical Results for the Final Report

International Nuclear Information System (INIS)

STEEN, F.H.

1999-01-01

This document is the final report for tank 241-U-102 grab samples. Five grab samples were collected from riser 13 on May 26, 1999 and received by the 222-S laboratory on May 26 and May 27, 1999. Samples 2U-99-3 and 2U-99-4 were submitted to the Process Chemistry Laboratory for special studies. Samples 2U-99-1, 2U-99-2 and 2U-99-5 were submitted to the laboratory for analyses. Analyses were performed in accordance with the Compatibility Grab Sampling and Analysis Plan for Fiscal year 1999 (TSAP) (Sasaki, 1999) and the Data Quality Objectives for Tank Farms Waste Compatibility Program (DQO) (Fowler 1995, Mulkey and Miller 1998). The analytical results are presented in the data summary report. None of the subsamples submitted for differential scanning calorimetry (DSC), total organic carbon (TOC) and plutonium 239 (Pu239) analyses exceeded the notification limits as stated in TSAP

The first multi-wavelength campaign of AXP 4U 0142+61 from radio to hard X-rays

NARCIS (Netherlands)

den Hartog, P.R.; Kuiper, L.; Hermsen, W.; Rea, N.; Durant, M.; Stappers, B.; Kaspi, V.M.; Dib, R.

2007-01-01

For the first time a quasi-simultaneous multi-wavelength campaign has been performed on an Anomalous X-ray Pulsar from the radio to the hard X-ray band. 4U 0142+61 was an INTEGRAL target for 1 Ms in July 2005. During these observations it was also observed in the X-ray band with Swift and RXTE, in

Periodic light variations of young stars U X Orion and S U Auriga

International Nuclear Information System (INIS)

Minikulov, N.Kh.; Abdulloev, S.Kh.

2007-01-01

The light curves of young variable stars U X Orion and S U Auriga are created from archive data of Institute of Astrophysics of the Academy of Sciences of the Republic of Tajikistan and other sources. It is established that periodic light variations of young stars U X Orion and S U Auriga occurs to duration of 36.4 and 29.8 years, accordingly. It is supposed that such periodic light variations are connected with existence a planetary system around these stars

Fast optical and X-ray variability in the UCXB 4U0614+09

Science.gov (United States)

Hakala, P. J.; Charles, P. A.; Muhli, P.

2011-09-01

We present results from several years of fast optical photometry of 4U0614+091 (V1055 Orionis), a candidate ultracompact X-ray binary most likely consisting of a neutron star and a degenerate secondary. We find evidence for strong accretion-driven variability at all epochs, which manifests itself as red noise. This flickering produces transient peaks in the observed power spectrum in the 15-65 min period range. Only in one of our 12 optical data sets can we see evidence for a period that cannot be reproduced using the red noise model. This period of 51 min coincides with the strongest period detected by Shahbaz et al. and can thus be taken as the prime candidate for the orbital period of the system. Furthermore, we find some tentative evidence for the X-ray versus optical flux anticorrelation discovered by Machin et al. using our data together with the all-sky X-ray monitoring data from RXTE/All Sky Monitor. We propose that the complex time series behaviour of 4U0614+09 is a result of drastic changes in the accretion disc geometry/structure on time-scales from hours to days. Finally, we want to draw attention to the interpretation of moderately strong peaks in the power spectra of especially accreting sources. Many of such 'periods' can probably be attributed to the presence of red noise (i.e. correlated events) in the data. Based on observations made with the Nordic Optical Telescope, operated on the island of La Palma jointly by Denmark, Finland, Iceland, Norway and Sweden, in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias. Uses results provided by the ASM/RXTE teams at MIT and at the RXTE SOF and GOF at NASA's GSFC.

Probing disk wind and other properties of 4U 1630-47

Science.gov (United States)

Bhattacharyya, Sudip

2015-09-01

The accreting Galactic black hole transient 4U 1630-47, which is currently in outburst, is an ideal source to probe two types of accreted matter ejection: (1) via disk wind and (2) via jet, both using the observed narrow spectral lines (Diaz Trigo et al., 2013, Nature, 504, 206; Neilsen et al. 2014; Diaz Trigo et al. 2014). Chandra gratings are ideal to study such lines. The source also showed indications of high-frequency (HF) quasi-periodic oscillations (QPOs) in a rather high (150-450 Hz) frequency range, which can be extremely useful to probe the strong gravity regime. The AstroSat satellite, because of its large area and high timing resolution in a broad energy band, can potentially detect and measure HF QPOs and probe the source broadband spectrum and state. Hence, our proposed 30 ks Chandra exposure, nearly contemporaneous with complementary AstroSat observations, will provide an excellent way to probe the accretion and ejection mechanism in the strong gravity regime.

Exosat observations of 4U 1705-44 - Type I bursts and persistent emission

International Nuclear Information System (INIS)

Langmeier, A.; Sztajno, M.; Hasinger, G.; Truemper, J.; Gottwald, M.; EXOSAT Observatory, Noordwijk, Netherlands)

1987-01-01

During four Exosat observations, the bright galactic X-ray source 4U 1705-44 exhibited persistent emission variations from 1.3 to 10.7 x 10 to the -9th ergs/sq cm per sec in the 1-20 keV band. Type I X-ray bursts have been detected from this source whose properties correlate with source intensity. The burst shape changed with increasing intensity from a slow burst profile with a decay time of 100 sec to a feast profile with a decay time of 25 sec. The spectrum during maximum was best-fitted by a two-component model involving a blackbody together with a Boltzmann-Wien law, and an additional iron K emission line. 28 references

Fragmentation and lateral scattering of 120 and 200 MeV/u {sup 4}He ions in water targets

Energy Technology Data Exchange (ETDEWEB)

Rovituso, Marta

2016-06-02

Along with an increased popularity of heavy ions in cancer therapy, {sup 4}He ions have regained the interest of the medical community as a compromise between protons and {sup 12}C ions. Although 2054 patients have been treated with {sup 4}He beams at Lawrence Berkeley Laboratory (LBL) (Berkeley CA, US) between 1975 and 1992, a comprehensive database of biological and physics measurements in the therapeutic energy range is still missing. One of the first steps necessary for introducing {sup 4}He ions in particle therapy, is the development of a dedicated treatment planning system, for which basic physics information such as the characterization of the beam lateral scattering and fragmentation cross sections describing the loss of primary particles and the build up of secondary fragments are required. Examination of data found in the literature reveals a gap in the therapeutic energy range. These measurements are essential for benchmarking not only the new model developed for the in-house treatment planning code TRiP98 (Treatment Planning for Particles), but also for already existing beam algorithms and for Monte Carlo codes like Geant4 and Fluka. The aim of this work is to provide fragmentation cross sections of {sup 4}He ions in the therapeutic energy range. The experimental data presented here were measured at Heidelberg Ion Beam Therapy Center (HIT) (Heidelberg, Germany) using 120 MeV/u and 200 MeV/u {sup 4}He beams. The attenuation of 200 MeV/u {sup 4}He beam in water was studied together with the build up of the secondary fragments produced by nuclear fragmentation processes. Target thicknesses between 1 and 25 cm H{sub 2}O were chosen to investigate nuclear fragmentation also beyond the maximum penetration depth of the {sup 4}He ions. The mixed radiation field produced by the interaction of 120 and 200 {sup 4}He ions with water targets (4.28 and 13.96 cm thick, respectively) has also been investigated in this work by measuring double differential cross

Strong decays of sc-bar mesons in the covariant oscillator quark model with the U tilde (4)DS x O(3, 1)L-classification scheme

International Nuclear Information System (INIS)

Maeda, Tomohito; Yamada, Kenji; Oda, Masuho; Ishida, Shin

2010-01-01

We investigate the strong decays with one pseudoscalar emission of charmed strange mesons in the covariant oscillator quark model. The wave functions of composite sc-bar mesons are constructed as the irreducible representations of the U tilde (4) DS xO(3,1) L . Through the observed mass and results of decay study we discuss a novel assignment of observed charmed strange mesons from the viewpoint of the U tilde (4) DS x O(3,1) L -classification scheme. It is shown that D s0 * (2317) and D s1 (2460) are consistently explained as ground state chiralons, appeared in the U tilde (4) DS xO(3,1) L scheme. Furthermore, it is also found that recently-observed D s1 * (2710) could be described as first excited state chiralon. (author)

Phase I study of Carzelesin (U-80,244) given (4-weekly) by intravenous bolus schedule

Science.gov (United States)

Awada, A; Punt, C J A; Piccart, M J; Tellingen, O Van; Manen, L Van; Kerger, J; Groot, Y; Wanders, J; Verweij, J; Wagener, D J Th

1999-01-01

Carzelesin is a cyclopropylpyrroloindole analogue which acts as a DNA-sequence-specific alkylating agent. In this phase I study, Carzelesin was given as a 4-weekly 10 min IV infusion to 51 patients with advanced solid tumours. Patients received a median of two courses (range 1–5) at one of nine dose levels: 24, 48, 96, 130, 150, 170, 210, 250 and 300 μg m−2. According to NCI-CTC criteria, non-haematological toxicities (grade 1/2) included fever, nausea and vomiting, mucositis and anorexia, none of which was clearly dose related. The dose-limiting toxicity was haematological and consisted mainly of neutropenia and to a lesser extent thrombocytopenia. From the dose level 150 μg m−2, the haematological toxicity (particularly thrombocytopenia) was delayed in onset, prolonged and cumulative in some patients. In several courses, double WBC nadirs occurred. The maximum tolerated dose for a single course was 300 μg m−2. From the dose level 170 μg m−2, the intended dose intensity could not be delivered to most patients receiving > 2 courses owing to cumulative haematological toxicity. The dose level with the best dose intensity for multiple courses was 150 μg m−2. The pharmacokinetics of Carzelesin and its metabolites (U-76,073; U-76,074) have been established in 31 patients during the first course of treatment using a HPLC method. Carzelesin exhibited linear pharmacokinetics. The concentration of U-76,074 (active metabolite) extended above the lower limit of quantitation (1 ng ml−1) for short periods of time and only at the higher dose levels. There was no relationship between neutropenia and the AUC of the prodrug Carzelesin, but the presence of detectable plasma levels of the active metabolite U-76,074 was usually associated with a substantial decrease in ANC values. © 1999 Cancer Research Campaign PMID:10188890

1980 outburst of 4U 0115+63 (V635 Cassiopeiae)

International Nuclear Information System (INIS)

Kriss, G.A.; Cominsky, L.R.; Remillard, R.A.; Williams, G.; Thorstensen, J.R.

1983-01-01

Optical observations of the proposed Be companion star (V635 Cas) to the hard transient X-ray pulsar 4U 0115+63 have been used to predict the 1980 December X-ray outburst, thus confirming the identification. V635 Cas increased in brightness by 1.7 magnitudes over the three months preceding the X-ray outburst, and strong, variable Hα emission was always present. These results demonstrate for the first time that increased optical activity in the Be companion star can lead directly to a ''hard'' transient X-ray outburst. There is a delay of approx.60 days between the onset of optical activity and the X-ray outburst. This delay and the absence of orbital modulation of the 1980 X-ray outburst (or any of the previous X-ray outburst) rule out direct accretion from a stellar wind. We suggest that the delay represents the time for material near the X-ray source to form an accretion disk and move inward toward the neutron star surface, and we discuss the observational implications of this interpretation. Future observations of similar transient events may provide a firm basis for the study of accretion disk dynamics

Synthesis of (3R)-3-(4-fluorophenylsulfonamido)-1,2,3,4-tetra-hydro-9-[4-3H] carbazolepropanoic acid

International Nuclear Information System (INIS)

Pleiss, Ulrich; Radtke, Martin; Schmitt, Peter

1990-01-01

(3R)-3-(4-Fluorophenylsulfonamido)-1,2,3,4-tetrahydro-9-[4- 3 H]carbazolepropanoic acid ( [ 3 H]BAY u 3405) (5) was synthesized by catalytic reduction of (3R)-3-(4-fluorophenylsulfonamido)-4-oxo-1,2,3,4-tetrahydro-9-carbazolepropanoic acid (4) with tritium. The precursor (4) was prepared by esterification and following oxidation of BAY u 3405 with 2,3-dichloro-5,6-dicyano-p-benzoquinone. 3 H NMR analysis of the final product showed the formation of [4α- 3 H]BAY us 3405 and [4β- 3 H]BAY u 3405 in a ratio of 1:1. (author)

Dicty_cDB: Contig-U09345-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U09345-1 gap included 1216 4 3361857 3360637 MINUS 4 5 U09345 1 0 1 0 0 0 2 0 0 0 0 0 0 0 Show Contig...-U09345-1 Contig ID Contig-U09345-1 Contig update 2002. 9.13 Contig sequence >Contig-U09345-1 (Contig-U09345-1Q) /CSM_Contig/Contig-U0934...AATGGTATTTTAAAAATAA Gap gap included Contig length 1216 Chromosome number (1..6, M) 4 Chromosome length 5430...ALFTSSNPKYGCSGCVQLKNQIESFSLSYEPYL NSAGFLEKPIFIVILEVDYNMEVFQTIGLNTIPHLLFIPSGSKPITQKGYAYTGFEQTSS QSISDFIYSHSKI...LLALFTSSNPKYGCSGCVQLKNQIESFSLSYEPYL NSAGFLEKPIFIVILEVDYNMEVFQTIGLNTIPHLLFIPSGSKPI

The Effect of Early Diagenesis on the 238U/235U Ratio of Platform Carbonates.

Science.gov (United States)

Tissot, F.; Chen, C.; Go, B. M.; Naziemiec, M.; Healy, G.; Swart, P. K.; Dauphas, N.

2017-12-01

In the past 15 years, the so-called non-traditional stable isotopes systems (e.g., Mg, Fe, Mo, U) have emerged as powerful tracers of both high-T and low-T geochemical processes (e.g., [1]). Of particular interest for paleoredox studies is the ratio of "stable" isotopes of U (238U/235U), which has the potential to track the global extent of oceanic anoxia (e.g., [2, 3]). Indeed, in the modern ocean, U exists in two main oxidation states, soluble U6+ and insoluble U4+, and has a mean residence time of 400 kyr ([4]), much longer than the global ocean mixing time (1-2 kyr). As such the salinity-normalized ocean is homogeneous with regards to both U concentrations and isotopes (δ238USW = -0.392±0.005 ‰, [2]). The value of δ238USW at any given time is therefore the balance between U input to the ocean, mainly from rivers, and U removal, mostly into biogenic carbonates, anoxic/euxinic sediments and suboxic/hypoxic sediments (e.g., [2, 5]). Because the 238U/235U ratio of the past ocean cannot be measured directly, it has to be estimated from the measurement of the 238U/235U ratio of a sedimentary rock and assuming a constant fractionation factor. Carbonates appear as a promising record since they span most of Earth's history, and the δ238U values of modern primary carbonate precipitates and well-preserved fossil aragonitic coral up to 600 ka are indistinguishable from that of seawater (e.g., [2, 6, 7]). Yet, the effect of secondary processes on the δ238U values of non-coral carbonates, which represent the bulk of the rock record, has only been studied in a handful of shallow samples (down to 40cm, [6]) and remains poorly understood. To investigate the effect of early diagenesis on the 238U/235U ratio of carbonates on the 30kyr to 1Myr timescale, we measured δ13C, δ18O, and δ238U in samples from a 220m long drill core from the Bahamas carbonate platform. In order to separate lattice bound U from secondary U we developed a leaching protocol applicable to carbonate

The Official Home Page of the U.S. Air Force

Science.gov (United States)

-world scenarios. (U.S. Navy photo by Mass Communication Specialist 3rd Class Anthony J. Rivera) A 27th from the 38th Rescue Squadron climb a ladder into an HH-60G Pave Hawk, Aug. 7, 2017, near Dog Island where a military working dog with the 379th Expeditionary Security Forces Squadron, detected

Complexes of Cd sup 2 sup +, U(O sub 2 ) sup 2 sup + and Th sup 4 sup + at radiotracer levels with phosphoric acid

International Nuclear Information System (INIS)

Bouhlassa, S.; El-Yahyaoui, A.; Brillard, L.; Hussonnois, M.; Guillaumont, R.

1994-01-01

In this work, we have turn to account the radiochemical techniques in order to investigate the complexation of Cd sup 2 sup +, U(O sub 2) sup 2 sup + and Th sup 2 sup +, at strength Mu=0,2, in various phosphoric media characterized by C sub ( H sub 3 P O sub 4) <= 4 M and 0.7 <= pH <= 4. The method chosen for this purpose is the liquid-liquid extraction of radioisotopes at tracer scale, with di(2-ethyl hexyl) phosphoric acid dissolved in benzene. The radionuclides used are Cd-109, U-233, U-230 and Th-227. Their distribution between the two phases are established by alpha or gamma spectrometric analysis. The analysis of the distribution data allows to define, in addition of species extracted in organic phase, the nature of phosphoric complexes which take place in aqueous media. Stability constants of these complexes and associated thermodynamic data are determined. 2 tabs.; 2 refs. (author)

Generation of HIV-1 primary isolates representative of plasma variants using the U87.CD4 cell line

NARCIS (Netherlands)

Heeregrave, Edwin J.; Ampofo, William K.; Tetteh, John K. A.; Ofori, Michael; Ofori, Sampson B.; Shah, Akram S.; Pollakis, Georgios; Paxton, William A.

2010-01-01

In order to obtain HIV-1 primary isolates in settings with limited access to donor PBMCs, a culture method was developed where patient PBMCs infected with HIV-1 were cultured together with U87.CD4 cells. Using this non-laborious method, it is possible to harvest virus solely on the basis of syncytia

INTEGRAL/IBIS detection of hard X-ray activity from the HMXB 4U 1036-56

DEFF Research Database (Denmark)

Sguera, V.; Bazzano, A.; Fiocchi, M.

2015-01-01

The Be high mass X-ray binary (HMXB) 4U 1036-56 has been recently detected by INTEGRAL/JEM-X during enhanced activity in the soft X-ray band 3-10 KeV (ATel #8425). On the contrary no emission was detected by INTEGRAL/IBIS in the band 22-60 keV, leading to a 3sigma upper limit of 6 mCrab. INTEGRAL...... was never in the field of view of JEM-X monitor during this observation. The IBIS/ISGRI spectrum is reasonably fitted by a power law with photon index 2.3+/-0.8. The average flux is 1.8 x 10-10 erg cm-2 s-1 (18-60 keV) which, at the 5 kpc source distance, translates into a luminosity of 5.4 x 1035 erg s-1....

Clinicians' perceptions of usefulness of the PubMed4Hh mobile device application for clinical decision making at the point of care: a pilot study.

Science.gov (United States)

Gartrell, Kyungsook; Brennan, Caitlin W; Wallen, Gwenyth R; Liu, Fang; Smith, Karen G; Fontelo, Paul

2018-05-08

Although evidence-based practice in healthcare has been facilitated by Internet access through wireless mobile devices, research on the effectiveness of clinical decision support for clinicians at the point of care is lacking. This study examined how evidence as abstracts and the bottom-line summaries, accessed with PubMed4Hh mobile devices, affected clinicians' decision making at the point of care. Three iterative steps were taken to evaluate the usefulness of PubMed4Hh tools at the NIH Clinical Center. First, feasibility testing was conducted using data collected from a librarian. Next, usability testing was carried out by a postdoctoral research fellow shadowing clinicians during rounds for one month in the inpatient setting. Then, a pilot study was conducted from February, 2016 to January, 2017, with clinicians using a mobile version of PubMed4Hh. Invitations were sent via e-mail lists to clinicians (physicians, physician assistants and nurse practitioners) along with periodic reminders. Participants rated the usefulness of retrieved bottom-line summaries and abstracts and indicated their usefulness on a 7-point Likert scale. They also indicated location of use (office, rounds, etc.). Of the 166 responses collected in the feasibility phase, more than half of questions (57%, n = 94) were answerable by both the librarian using various resources and by the postdoctoral research fellow using PubMed4Hh. Sixty-six questions were collected during usability testing. More than half of questions (60.6%) were related to information about medication or treatment, while 21% were questions regarding diagnosis, and 12% were specific to disease entities. During the pilot study, participants reviewed 34 abstracts and 40 bottom-line summaries. The abstracts' usefulness mean scores were higher (95% CI [6.12, 6.64) than the scores of the bottom-line summaries (95% CI [5.25, 6.10]). The most frequent reason given was that it confirmed current or tentative diagnostic or

Synthesis of (+)-(3R)-3-(4-fluorophenylsulfonamido)-1,2,3,4-tetrahydro-9-[5,6,7,8,12,13-u-14C]carbazoleppropanoic acid, [14C]BAY u 3405

International Nuclear Information System (INIS)

Radtke, M.; Boberg, M.; Pleiss, U.; Rosentreter, U.

1994-01-01

The title compound [ 14 C]BAY u 3405 (1) was synthesized as part of 8-step sequence. Starting from [U- 14 C]aniline hydrogensulfate the final product 1 was obtained with a specific activity of 741 MBq/mmol (20 mCi/mmol) and a radiochemical purity of > 98 % in an overall yield of 6 and 10 % depending on the method. (author)

Unusual X-ray burst profiles from 4U/MXB 1636-53

Science.gov (United States)

Sztajno, M.; Truemper, J.; Pietsch, W.; Van Paradijs, J.; Stollman, G.

1985-01-01

During a one day Exosat observation eight X-ray bursts from 4U/MXB 1636-53 are observed. Four of these were very unusual. Their peak fluxes were relatively low, and they showed a distinct double peak in their bolometric flux profiles. These new double-peaked bursts are unexplained by presently available models of X-ray bursts. It is possible that the energy release in these bursts proceeds in two 'steps'. The burst profiles are not the result of an expansion and subsequent contraction of the photosphere of the neutron star. Thus, they are very different from previously observed bursts which do show a double peak in certain energy ranges but not in their bolometric flux profiles; these are satisfactorily explained in terms of photospheric radius expansion and contraction. The anticorrelation between the apparent blackbody radius and blackbody temperature is discussed in terms of the nonPlanckian character of burst spectra and it is concluded that the model calculations reported by London, Taam, and Howard in 1984 give a reasonable first-order description of the observed apparent radius changes in X-ray bursts.

Restoration of u.v.-induced excision repair in Xeroderma D cells transfected with the denV gene of bacteriophage T4

International Nuclear Information System (INIS)

Arrand, J.E.; Squires, S.; Bone, N.M.; Johnson, R.T.

1987-01-01

The heritable DNA repair defect in human Xeroderma D cells, resulting in failure to incise at u.v. light-induced pyrimidine dimers, has been partially but stably corrected by transfection of immortalised cells with the denV pyrimidine dimer glycosylase gene of bacteriophage T4. Transfectants selected either for a dominant marker on the mammalian vector carrying the prokaryotic gene or for dominant marker plus resistance to killing by u.v. light, were shown to express the denV gene to varying degrees. denV expression results in significant phenotypic change in the initially repair-deficient, u.v.-hypersensitive cells. Increased resistance to u.v. light and more rapid recovery of replicative DNA synthesis following u.v. irradiation were correlated with improved repair DNA synthesis and with a novel dimer incision capability present in denV transfected Xeroderma cells but not as evident in transfected normal cells. Most transfectants contain a single integrated copy of the denV gene; increase in denV copy number does not result in either increased gene expression or enhanced survival to u.v. light. Results show that expression of a heterologous prokaryotic repair gene can partially compensate for the genetic defect in a human Xeroderma D cell. (author)

75 FR 75486 - Maritime Security Directive 104-6 (Rev. 4); Guidelines for U.S. Vessels Operating in High Risk...

Science.gov (United States)

2010-12-03

... Directive 104-6 (Rev. 4); Guidelines for U.S. Vessels Operating in High Risk Waters AGENCY: Coast Guard, DHS... Maritime Transportation Security Act (MTSA) on international voyages through or in designated high risk... MARSEC Directives are available at your local Captain of the Port (COTP) office. Phone numbers and...

Inhibition of CLIC4 enhances autophagy and triggers mitochondrial and ER stress-induced apoptosis in human glioma U251 cells under starvation.

Directory of Open Access Journals (Sweden)

Jiateng Zhong

Full Text Available CLIC4/mtCLIC, a chloride intracellular channel protein, localizes to mitochondria, endoplasmic reticulum (ER, nucleus and cytoplasm, and participates in the apoptotic response to stress. Apoptosis and autophagy, the main types of the programmed cell death, seem interconnected under certain stress conditions. However, the role of CLIC4 in autophagy regulation has yet to be determined. In this study, we demonstrate upregulation and nuclear translocation of the CLIC4 protein following starvation in U251 cells. CLIC4 siRNA transfection enhanced autophagy with increased LC3-II protein and puncta accumulation in U251 cells under starvation conditions. In that condition, the interaction of the 14-3-3 epsilon isoform with CLIC4 was abolished and resulted in Beclin 1 overactivation, which further activated autophagy. Moreover, inhibiting the expression of CLIC4 triggered both mitochondrial apoptosis involved in Bax/Bcl-2 and cytochrome c release under starvation and endoplasmic reticulum stress-induced apoptosis with CHOP and caspase-4 upregulation. These results demonstrate that CLIC4 nuclear translocation is an integral part of the cellular response to starvation. Inhibiting the expression of CLIC4 enhances autophagy and contributes to mitochondrial and ER stress-induced apoptosis under starvation.

Analysis of gamma dose for 4,8 gU/cm3 density silicide core at the RSG-GAS reactor using MCNP code

International Nuclear Information System (INIS)

Ardani

2011-01-01

Radiation safety analysis should be done following of substitution of fuel density of 2.96 gU/cc to density of 4,8 gU/cc silicide fuels for the RSG-GAS reactor. MCNP-5 code has been used to perform gamma dose calculation of the RSG-GAS reactor. Gamma radiation source at reactor consists of capture gamma rays, prompt fission gamma rays, and gamma rays of decay of fission and activation products. The strength of the prompt fission gamma rays is obtained by gamma releases of fission process of U-235 and reactor power of 30 MWt., during 46,6 days operation. Radiation dose is calculated at the experimental hall by detection point at the surface of outer of biological shielding and the operation hall by detection point at the top of the pool. The calculation is conducted at reactor on the normal operation and on the worst postulated accident causing the water level at the pool decreases. Calculation result shows that the biggest source strength of gamma rays come from the decay process. The highest calculated dose at the experiment hall is 4,07x10 -3 μSv/h, far from the maximum external dose permitted 25 μSv/h. The highest calculated dose at the operation hall is 19.98 μSv/h. Even though the calculated dose is still acceptable but this is close to the maximum permitted dose for worker. It concluded that loading of 4,8 gU/cc silicide fuel for the RSG-GAS still safe. (author)

Voltametric determination of O:U relation in uranium oxide

International Nuclear Information System (INIS)

Carvalho, F.M.S. de; Abrao, A.

1988-07-01

Uranium oxide samples are dissolved in hot concentrated H 3 PO 4 - H 2 SO 4 mixture and the solution diluted with 1M H 2 SO 4 . One aliquot of such solution (A) is used to record the first voltamogram which gives the U(VI) content. To a second aliquot HNO 3 and H 2 O 2 is added to oxidise uranium to the hexavalent state (B) and the second voltamogram is recorded from 0.0 to 0.4 V X SCE. The O:U ratio in the original sample is calculated by the expression: O/U = 2.000 + [U (VI) soln.A/% U(VI) soln. B]. The method provides an accurate means for determining O to U ratios in high-purity uranium dioxide, fuel pellets and a variety of oxides prepared for developmental work on ceramic fuel materials. (author) [pt

Charge distribution studies in the fast-neutron-induced fission of sup 2 sup 3 sup 2 Th, sup 2 sup 3 sup 8 U, sup 2 sup 4 sup 0 Pu and sup 2 sup 4 sup 4 Cm

CERN Document Server

Naik, H; Iyer, R H

2003-01-01

Charge distribution studies for heavy-mass fission products were carried out in the fast-neutron-induced fission of sup 2 sup 3 sup 2 Th, sup 2 sup 3 sup 8 U, sup 2 sup 4 sup 0 Pu and sup 2 sup 4 sup 4 Cm using radiochemical and gamma-ray spectrometric techniques. The width parameter(sigma sub Z /sigma sub A), the most probable charge/mass (Z sub P /A sub P), the charge polarization (DELTA Z) and the slope of charge polarization [ delta(DELTA Z)/delta A sup '] as a function of the fragment mass (A sup ') were deduced. The average charge dispersion parameter (left angle sigma sub Z right angle) and proton odd-even effect (delta sub p) were also obtained for these fissioning systems. The left angle sigma sub Z right angle and delta sub p values in the fissioning systems sup 2 sup 4 sup 1 Pu sup * and sup 2 sup 4 sup 5 Cm sup * were determined for the first time. The delta(DELTA Z)/delta A sup ' value is also determined for the first time in the fissioning systems sup 2 sup 3 sup 9 U sup * , sup 2 sup 4 sup 1 Pu...

Dicty_cDB: Contig-U12316-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U12316-1 gap included 1238 4 1925901 1927143 PLUS 5 6 U12316 0 4 1 0 0 0 0 0 0 0 0 0 0 0 Show Contig...-U12316-1 Contig ID Contig-U12316-1 Contig update 2002.12.18 Contig sequence >Contig-U12316-1 (Contig-U12316-1Q) /CSM_Contig/Contig-U12316...GAGTTGAAGATTTAGTTTTATCAGNANGAANAAATAAGAT Gap gap included Contig length 1238 Chromosome number (1..6, M) 4 C...,915,1174 Translated Amino Acid sequence lvqhhyh*liscvivllksmv*isqvhivvhlfmfvn*qyileih*iptlknlskiftig...lip*r*rtrkttn*kiknny*itketkiqs*t*rvmmmi*vedlvls xxxnk Frame B: lvqhhyh*liscvivllksmv*isqvhivvhlfmfvn*qyileih*iptlknlskiftig

4U 1626-67 as Seen by Suzaku Before and After the 2008 Torque Reversal

Science.gov (United States)

Camero-Arranz, A.; Pottschmidt, K.; Finger, M. H.; Ikhsanov, N. R.; Wilson-Hodge, C. A.; Marcu, D. M.

2012-01-01

Aims. The accretion-powered pulsar 4U 1626-67 experienced a new torque reversal at the beginning of 2008, after about 18 years of steadily spinning down. The main goal of the present work is to study this recent torque reversal that occurred in 2008 February. Methods. We present a spectral analysis of this source using two pointed observations performed by Suzaku in 2006 March and in 2010 September. Results. We confirm with Suzaku the presence of a strong emission-line complex centered on 1 keV, with the strongest line being the hydrogen-like Ne Lya at 1.025(3) keV. We were able to resolve this complex with up to seven emission lines. A dramatic increase of the intensity of the Ne Lya line after the 2008 torque reversal occurred, with the equivalent width of this line reaching almost the same value measured by ASCA in 1993. We also report on the detection of a cyclotron line feature centered at approximately 37 keV. In spite of the fact that an increase of the X-ray luminosity (0.5-100keV) of a factor of approximately 2.8 occurred between these two observations, no significant change in the energy of the cyclotron line feature was observed. However, the intensity of the approximately 1 keV line complex increased by an overall factor of approximately 8. Conclusions. Our results favor a scenario in which the neutron star in 4U 1626-67 accretes material from a geometrically thin disk during both the spin-up and spin-down phases.

A Link Between X-ray Emission Lines and Radio Jets in 4U 1630-47?

Science.gov (United States)

Neilsen, Joseph; Coriat, Mickaël; Fender, Rob; Lee, Julia C.; Ponti, Gabriele; Tzioumis, A.; Edwards, Phillip; Broderick, Jess

2014-06-01

Recently, Díaz Trigo et al. reported an XMM-Newton detection of relativistically Doppler-shifted emission lines associated with steep-spectrum radio emission in the stellar-mass black hole candidate 4U 1630-47 during its 2012 outburst. They interpreted these lines as indicative of a baryonic jet launched by the accretion disk. We present a search for the same lines earlier in the same outburst using high-resolution X-ray spectra from the Chandra HETGS. While our observations (eight months prior to the XMM-Newton campaign) also coincide with detections of steep spectrum radio emission by the Australia Telescope Compact Array, we find a strong disk wind but no evidence for any relativistic X-ray emission lines. Indeed, despite ˜5× brighter radio emission, our Chandra spectra allow us to place an upper limit on the flux in the blueshifted Fe XXVI line that is ˜20× weaker than the line observed by Díaz Trigo et al. Thus we can conclusively say that radio emission is not universally associated with relativistically Doppler-shifted emission lines in 4U 1630-47. We explore several scenarios that could explain our differing results, including variations in the geometry of the jet or a mass-loading process or jet baryon content that evolves with the accretion state of the black hole. We also consider the possibility that the radio emission arises in an interaction between a jet and the nearby ISM, in which case the X-ray emission lines might be unrelated to the radio emission.

Rare-Earth Oxide Ion (Tm3+, Ho3+, and U3+) Doped Glasses and Fibres for 1.8 to 4 Micrometer Coherent and Broadband Sources

Science.gov (United States)

2006-07-24

oxide ( TeO2 ) , fluorine- containing silicate (SiOF2) and germanate (GeOF2) glass hosts for each dopant by characterising the spectroscopic properties...Earth Oxide Ion (Tm3+, Ho3+, And U3+) Doped Glasses And Fibres For 1.8 To 4 Micrometer Coherent And Broadband Sources 5c. PROGRAM ELEMENT NUMBER 5d...Rare-earth oxide ion (Tm3+, Ho3+, and U3+) doped glasses and fibres for 1.8 to 4 micrometer coherent and broadband sources Report prepared

Hydrogeochemical applications of natural isotope of the U (4n+2) and Th(4n) series in Morro do Ferro, Pocos de Caldas (MG), Brazil

International Nuclear Information System (INIS)

Bonotto, D.M.

1987-01-01

Uranium and thorium isotopic analysis were performed on well spoils of the ore body at Morro do Ferro, Pocos de Caldas (MG), Brazil, using groundwater from several boreholes in the area and surface water from a stream and that originates at the base of the hill. For uranium and thorium extraction, a chemical process was applied to samples; activites of 228 Th and 232 Th radioisotopes (4n+2 series) were determined by alpha spectrometry. The uranium concentration and 234 U/ 238 U isotope ratio in groundwater were applied to developed models for deducing proportions of water in a mixture and for characterizing uranium accumulation. The correlation between variability in concentration of uranium dissolved in groundwater and alteration of the level of the water table due to infiltration of rainfall was observed. Chemical analysis of the major and minor compounds for groundwater of the ore body zone were done. (Author) [pt

Dicty_cDB: Contig-U06307-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U06307-1 no gap 637 6 29174 29801 PLUS 4 5 U06307 4 0 0 0 0 0 0 0 0 0 0 0 0 0 Show Contig...-U06307-1 Contig ID Contig-U06307-1 Contig update 2002. 9.13 Contig sequence >Contig-U06307-1 (Contig...-U06307-1Q) /CSM_Contig/Contig-U06307-1Q.Seq.d CCCGCGTCCGAATGCCTCGTATTTTACACACTATGCTCCGTGTGGGTAAT TTAG...ATAGTATTTTTATTTTATT CTTTTTCTTTTAAAAATTTTTTATATTGTCAACAATATAATCAAATAAAT GTATTTAATTATCGGGTATTAAAAAAAAAAAAAAAAA Gap no gap Contig...own update 2004. 6.10 Homology vs CSM-cDNA Query= Contig-U06307-1 (Contig-U06307-1Q) /CSM_Contig/Contig-U063

Itinerant f-electron behavior in Ce and U compounds

International Nuclear Information System (INIS)

Crabtree, G.W.

1985-04-01

The experimentally observed Fermi surface properties in URh 3 , UIr 3 , UGe 3 , CeSn 3 , CeB 6 , U 3 As 4 , U 3 P 4 , and CeSb are reviewed. For the compounds with no magnetic order, band structure models of the Fermi surface geometry are confirmed and f-ligand hybridization is found to be dominant. For CeB 6 , U 3 As 4 , and U 3 P 4 the experiments show that both local moments and f hybridization are important. In CeSb new data can be explained by a purely local model with no f-hybridization

Chandra Takes on Heavy Jets and Massive Winds in 4U 1630-47

Science.gov (United States)

Neilsen, Joey

2014-11-01

Recently, Díaz Trigo et al. reported the discovery of relativistic baryons in a jet in XMM/ATCA observations of the 2012 outburst of the black hole 4U 1630-47. We present a search for a similarly massive jet earlier in the same outburst using high-resolution X-ray spectra from the Chandra HETGS. Despite a detection of radio emission with ATCA, we find no evidence of a heavy jet in the X-ray spectrum, with tight upper limits on the relativistic emission lines seen by Díaz Trigo eight months later. Instead, we find deep absorption lines from a massive, highly ionized disk wind, whose properties can be probed with detailed photoionization models. We explore several scenarios to explain the two modes of massive outflow in this remarkable black hole system.

U(IV) chalcogenolates synthesized via oxidation of uranium metal by dichalcogenides.

Science.gov (United States)

Gaunt, Andrew J; Scott, Brian L; Neu, Mary P

2006-09-04

Treatment of uranium metal with dichalcogenides in the presence of a catalytic amount of iodine in pyridine affords molecular U(IV) chalcogenolates that do not require stabilizing ancillary ligands. Oxidation of U(0) by PhEEPh yields monomeric seven-coordinate U(EPh)4(py)3 (E = S(1), Se(2)). The dimeric eight-coordinate complexes [U(EPh)2(mu2-EPh)2(CH3CN)2]2 (E = S(3), Se(4)) are obtained by crystallization from solutions of 1 and 2 dissolved in acetonitrile. Oxidation of U(0) by pySSpy and crystallization from thf yields nine-coordinate U(Spy)4(thf) (5). Incorporation of elemental selenium into the oxidation of U(0) by PhSeSePh results in the isolation of [U(py)2(SePh)(mu3-Se)(mu2-SePh)]4.4py (6), a tetrameric cluster in which each U(IV) ion is eight-coordinate and the U4Se4 core forms a distorted cube. The compounds were analyzed spectroscopically and the single-crystal X-ray structures of 1 and 3-6 were determined. The isolation of 1-6 represents six new examples of actinide chalcogenolates and allows insight into the nature of "hard" actinide ion-"soft" chalcogen donor interactions.

The 4-fold fission in 40Ar + 209Bi, 197Au and 159Tb reactions at 25MeV/u

International Nuclear Information System (INIS)

Dai, G.X.; Wu, H.Y.; He, Z.Y.; Luo, Q.Z.; Duan, L.M.; Zhang, B.G.; Qi, Y.J.; Li, Z.Y.; Jin, G.M.; Wen, W.X.

1995-01-01

The paper presents the 4-fold fission or fragmentation of hot nuclei produced in 25MeV/u 40 Ar+ 209 Bi, 197 Au and 159 Tb reactions. The events with 4 massive fragments emitted with angles larger than 36 were detected by 8 PPACs with area of 25x20cm 2 . The TKE, distributions of mass and velocity for the four fragments have been obtained. ((orig.))

Dicty_cDB: Contig-U16108-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U16108-1 gap included 1456 4 1889609 1888449 MINUS 4 6 U16108 0 0 2 0 1 0 1 0 0 0 0 0 0 0 Show Contig...-U16108-1 Contig ID Contig-U16108-1 Contig update 2004. 6.11 Contig sequence >Contig-U16108-1 (Contig-U16108-1Q) /CSM_Contig/Contig-U1610...AAAATCA TAAAATCAAAAATTGTATAATTAAAATAAAAATAAAAAAAAAAACAAAAA TAAAAAAAAAAAACAA Gap gap included Contig length 1...DFLSQFYGELN QPSLNNLTENIITIDQSSFIPIGYTTITAGLNNFAYAYIPTSCKNDKSLCSIHVAFHGCL QTVATIGDNFYTKTGYNEIAETNNIIILYPQALET...---NYVNNDNIKTMFDIQSEHAFITNSFGNNCTYLGPDYINNCNFNAPWDFLSQFYGELN QPSLNNLTENIITIDQSSFIPIGYTTITAGLNNFAYAYIPTSCKNDKSLCSIHVAFHGCL QTVATIG

Dicty_cDB: Contig-U12049-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U12049-1 gap included 2563 4 3071598 3069091 MINUS 9 17 U12049 0 0 0 0 2 0 0... 1 4 1 1 0 0 0 Show Contig-U12049-1 Contig ID Contig-U12049-1 Contig update 2002.12.18 Contig sequence >Contig-U12049-1 (Contig...-U12049-1Q) /CSM_Contig/Contig-U12049-1Q.Seq.d TAATGAAGGTAGTAATAATAATATAGTTGAAGCATCAAAAGA...TATCATTTAAACTGAAAAAAGTC CAAAAGATTTATGCAATGATTGCTGCGAATATGCTGCAACTTGTTCTCAT TAAAAATAAACAAAAAAATAATA Gap gap included Contig...disngqcvyseiidcgsssienss nqesssdidittastlgstiastigstigltstttttttsqttgtpttppqtvseipisl astistspvsdegtiastiatt

A reprocessing model for the ultraviolet and optical light from 4U 1820-30

Science.gov (United States)

Arons, Jonathan; King, Ivan R.

1993-01-01

We show that the recently discovered optical and ultraviolet light from the X-ray burst source 4U 1820-30 in the globular cluster NGC 6624 is due to reprocessing of the X-rays in the outer regions of an optically thick, geometrically thin accretion disk. We suggest that observation of orbital modulation of the reprocessed light, due to the variable contribution made as the heated face of the companion turns toward and away from the observer, would provide constraints on the inclination of the binary orbit, and we suggest that detection in the reprocessed flux of the 'red noise' already observed in the X-rays would provide useful constraints on the geometry and physics of the accretion disk.

Stopping powers of havar and effective charge for 1.4-3.2 MeV/u {sup 127}I-ions

Energy Technology Data Exchange (ETDEWEB)

Alanko, T. E-mail: tommi.alanko@phys.jyu.fi; Hyvoenen, J.; Kylloenen, V.; Raeisaenen, J.; Virtanen, A

2000-06-01

Stopping powers of havar for 1.4-3.2 MeV/u {sup 127}I-ions have been determined by the transmission technique using two geometrical arrangements. No previous data have been published for havar with this ion. The experimental data are compared with predictions obtained by using Bragg's additivity rule with various parametrizations of the stopping power found in the literature. The values obtained by the parametrizations underestimate the experimental data by 5-11%. The empirical correction scheme of Thwaites yields values in rather good agreement with the present results, especially at energies above 1.9 MeV/u. The effective charges of the {sup 127}I ions were also deduced from the experimental data.

Analysis list: Klf4 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Klf4 Breast,Embryonic fibroblast,Pluripotent stem cell + mm9 http://dbarchive.biosc...iencedbc.jp/kyushu-u/mm9/target/Klf4.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Klf4.5.tsv ...http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Klf4.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Klf4....Breast.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Klf4....Embryonic_fibroblast.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Klf4.Pluripotent_stem_cell.ts

Analysis list: ELK4 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available ELK4 Prostate,Uterus + hg19 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/ELK4.1.tsv http:...//dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/ELK4.5.tsv http://dbarchive.biosciencedbc....jp/kyushu-u/hg19/target/ELK4.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/ELK4.Prostate.tsv,http:...//dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/ELK4.Uterus.tsv http://dbarch...ive.biosciencedbc.jp/kyushu-u/hg19/colo/Prostate.gml,http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/Uterus.gml ...

Analysis list: ATF4 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available ATF4 Blood,Others + hg19 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/ATF...4.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/ATF4.5.tsv http://dbarchive.biosciencedbc.jp/...kyushu-u/hg19/target/ATF4.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/ATF4.Blood.tsv,http://dbarchive.bioscience...dbc.jp/kyushu-u/hg19/colo/ATF4.Others.tsv http://dbarchive.bioscience...dbc.jp/kyushu-u/hg19/colo/Blood.gml,http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/Others.gml ...

Dicty_cDB: Contig-U15566-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U15566-1 gap included 1830 4 3730704 3729599 MINUS 4 8 U15566 0 0 1 0 1 0 0 0 2 0 0 0 0 0 Show Contig...-U15566-1 Contig ID Contig-U15566-1 Contig update 2004. 6.11 Contig sequence >Contig-U15566-1 (Contig-U15566-1Q) /CSM_Contig/Contig-U1556...CAAGATCCAA TGGAATTTTAATAATAAATAAGAATAATAAAAAAAAAAAA Gap gap included Contig length 1830 Chromosome number (1...ITLTPSEDIEKKLKEI QDENLSNSEIWFAVKSYLEDNNLKEHLYNLVFHYTMPRIDEPVTIGLDHLGNVLVSNR*c tflvvvvvytfgcriephni*qerivlqf*...asilnhirvelsqnqipilkrsfdqillphfekc iieeqqiftnekqrknflsllpisykrqdrkipltpsediekklkeiqdenlsnseiwfa vksylednnlkehlynlvfhytmpridepvtig

Dicty_cDB: Contig-U15058-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U15058-1 no gap 1987 4 4423139 4424727 PLUS 2 4 U15058 0 0 0 0 0 0 0 0 1 0 1 0 0 0 Show Contig...-U15058-1 Contig ID Contig-U15058-1 Contig update 2004. 6.11 Contig sequence >Contig-U15058-1 (Contig...-U15058-1Q) /CSM_Contig/Contig-U15058-1Q.Seq.d AAAAAAGGTTACTCACAAAGTTAAAGAAATCAATGAAAGATTTACCACCC...ACTCAAGGGGGTAGGAGAATAAAATCAACCGATTATCCAGGCNTTAAG CGACCTTTTTCCCAAAAAAAAAAGATGTTCAGAAAAT Gap no gap Contig len...srx*atffpkkkdvq k own update 2004. 6.23 Homology vs CSM-cDNA Query= Contig-U15058-1 (Contig-U15058-1Q) /CSM_Contig/Contig

The Influence of Uranium Content and PVA/U Ratio on Physical Propertiesof PVA-U Gel and Its Oxide

International Nuclear Information System (INIS)

Damunir; W, Bangun; Indra-Suryawan; Endang-Nawangsih

2000-01-01

The influence of uranium content and PVA/U ratio on physical propertiesof PVA-U gel and its oxide has been investigated. Fifty milliliters of uranylnitrate solution containing 100 g U/l was neutralized using 1M NH 4 0H. Thesolution was converted into PVA-U sol by adding 9.18 % PVA while mixed andheated at 80 o C for 20 minutes. In order to find spherical gel, the solsolution was dropped into a 5 M NH 4 0H solution at room temperature. Theshape formed of the gels small spherical, shape of the formed gels werefiltered, washed and heated at 120 o C. After that the gels were calcined at800 o C for 4 hours. The formed U 3 O 8 particles. Under a similar method, theinfluence of uranium content from 150-400 g/l and the influence of PVA/Uratio of 6.5-12.5 % in 100 g U/l were studied. Characterization of the resultwas obtained from physical properties of the gel and its oxide in the form ofdensity using pycnometer, surface area using surface areameter with N 2 asabsorbent and particle size/ shape using a loop and optical microscope. Theexperimental results showed that both uranium content and PVA/U ratioaffected the physical properties of the kernel properties. The best resultoccurred at uranium content of 100 g/l and PVA/U 9.18 %. The resulted gelwith solid content of 89.17 %, density of 3.36 g/l and size of 124 μm. Theresulted oxide U 3 0 8 had density of 7.98 g U/l, surface area of specific of0.449 m 2 /g and grain size of 810 μm. (author)

U.S. - UK - Canada Trilateral Symposium

Science.gov (United States)

2009-10-02

e . 4. Procedures for intra-community arms transfers simplified. 5 Retransfer controls disco raged b t m st be. u u u complied with. Li d...IRIS – T • Airbus A310 refueller 10 FUTURE OF TRANSATLANTIC ARMAMENTS COOPERATION 1996 VISION – “I believe that national security – ours and that

Dicty_cDB: Contig-U13891-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U13891-1 no gap 1355 6 799802 798446 MINUS 4 4 U13891 0 0 0 0 1 1 1 0 0 0 1 0 0 0 Show Contig...-U13891-1 Contig ID Contig-U13891-1 Contig update 2002.12.18 Contig sequence >Contig-U13891-1 (Contig...-U13891-1Q) /CSM_Contig/Contig-U13891-1Q.Seq.d TTTTAAAATATTTCAAAATTAGCGAGCACGCATTCGCATATAAATATATT ...ACAAATAAAAAAAAAAAATAAAAAAAATA ATTTA Gap no gap Contig length 1355 Chromosome numb...own update 2004. 6.10 Homology vs CSM-cDNA Query= Contig-U13891-1 (Contig-U13891-1Q) /CSM_Contig/Contig-U138

Why linear Birch and U/sub s/-U/sub p/ expansions work

International Nuclear Information System (INIS)

Grover, R.

1987-11-01

The equivalence of the Birch-Murnaghan equation to a linear U/sub s/-U/sub p/ equation was illustrated in the previous paper. Here we show in a direct manner how the virial theorem and the effect of core exclusion on valence electron kinetic energy changes lead to the convergence of the Eulerian strain expansion about the zero-pressure state. 7 refs., 4 tabs

Dicty_cDB: Contig-U14400-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U14400-1 no gap 1939 4 4053811 4055750 PLUS 5 7 U14400 0 0 2 0 0 1 0 0 1 1 0 0 0 0 Show Contig...-U14400-1 Contig ID Contig-U14400-1 Contig update 2002.12.18 Contig sequence >Contig-U14400-1 (Contig...-U14400-1Q) /CSM_Contig/Contig-U14400-1Q.Seq.d CATTACCAATAAATTTATCTGCTTCAACACCTATACCAATGACATCACCA...AGGTTTATAAAATATATTGAATCAATTTTTGATTAAA Gap no gap Contig length 1939 Chromosome number (1..6, M) 4 Chromosome...HQQQQSKTVTSSTTSTETTTTVESSTTSTTITTSTSTPIPTTITTTPTTPI NSDNSWTFTSFSPKVFKEIRRYYGVDEEFLKSQENSSGIVKFLEVQTIGRSGSFFY

Dicty_cDB: Contig-U10709-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U10709-1 gap included 1228 4 757921 759149 PLUS 2 3 U10709 0 0 0 1 1 0 0 0 0 0 0 0 0 0 Show Contig...-U10709-1 Contig ID Contig-U10709-1 Contig update 2002.12.18 Contig sequence >Contig-U10709-1 (Contig...-U10709-1Q) /CSM_Contig/Contig-U10709-1Q.Seq.d ATTAGTAACACAGACATTGGTAACACGAATTTATTACCACCATCAC...ATGTTTAGGTGATAATACTCATAGTCAA Gap gap included Contig length 1228 Chromosome number (1..6, M) 4 Chromosome le...LDIFLIQIGAAIMGSNQFIQHAINIYNLEDWFEIEPFNG SLNKSTEGTPTTTSSQPPSTPSKQTSLRNSAGTVPTTPSQSSSTIVPTLDTIGETTTTTT TTATTTT

Dicty_cDB: Contig-U15323-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U15323-1 no gap 1230 2 3760829 3759661 MINUS 76 108 U15323 2 0 21 0 9 4 0 0 22 4 13 0 1 0 Show Contig...-U15323-1 Contig ID Contig-U15323-1 Contig update 2004. 6.11 Contig sequence >Contig-U15323-1 (Contig-U15323-1Q) /CSM_Contig/Contig-U1532...TAAAATTTAAGCAATCATTCCAT Gap no gap Contig length 1230 Chromosome number (1..6, M) 2 Chromosome length 846757...VGLLVFFNILYCTPLYYILFFFKMNSKFADELIATAKAIVAPGKGILAADESTNTIGAR FKKINLENNEENRRAYRELLIGTGNGVNEFIGGIILYEETLYQKMADG...MNSKFADELIATAKAIVAPGKGILAADESTNTIGAR FKKINLENNEENRRAYRELLIGTGNGVNEFIGGIILYEETLYQK

Analysis list: Smarca4 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Smarca4 Adipocyte,Blood,Breast,Embryo,Embryonic fibroblast,Epidermis,Pluripotent st...em cell + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Smarca4.1.tsv http://dbarchive.bioscienc...edbc.jp/kyushu-u/mm9/target/Smarca4.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Smarca4.10.t...sv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Smarca4.Adipocyte.tsv,http...://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Smarca4.Blood.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Smarca

Analysis list: TEAD4 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available TEAD4 Blood,Breast,Digestive tract,Liver,Neural,Pluripotent stem cell,Uterus + hg19... http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/TEAD4.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/TEA...D4.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/TEAD4.10.tsv http://dbarch...ive.biosciencedbc.jp/kyushu-u/hg19/colo/TEAD4.Blood.tsv,http://dbarchive.bioscien...cedbc.jp/kyushu-u/hg19/colo/TEAD4.Breast.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/TEAD4.Dige

Analysis list: Tcf4 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Tcf4 Digestive tract,Epidermis,Liver + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Tcf4....1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Tcf4.5.tsv http://dbarchive.b...iosciencedbc.jp/kyushu-u/mm9/target/Tcf4.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Tcf4.Dig...estive_tract.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Tcf4.Epiderm...is.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Tcf4.Liver.tsv http://dbarchive.biosciencedbc.jp/

Analysis list: Atf4 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Atf4 Blood,Embryonic fibroblast,Epidermis + mm9 http://dbarchive.biosciencedbc.jp/k...yushu-u/mm9/target/Atf4.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Atf4.5.tsv http://dbarchive.bioscience...dbc.jp/kyushu-u/mm9/target/Atf4.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Atf...4.Blood.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Atf4.Embryonic_fi...broblast.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Atf4.Epidermis.tsv http://dbarchive.bioscience

A Spectral Analysis of the X-Ray Pulsar 4U 1907+09 obtained at thePeriastron Passage with the XMM-Newton Observatory

NARCIS (Netherlands)

Balman, Solen; Mendez, Mariano; Diaz Trigo, Maria; Inam, Cagdas; Baykal, Altan

2010-01-01

We present results from a 20 ksec observation of the wind-accreting X-ray pulsar 4U 1907+09 obtained using the XMM-Newton Observatory at the periastron passage. The XMM-Newton spectrum allows us to study the continuum emission and the emission line at 6.4 keV with the high sensitivity and

Automated cell tracking and analysis in phase-contrast videos (iTrack4U): development of Java software based on combined mean-shift processes.

Science.gov (United States)

Cordelières, Fabrice P; Petit, Valérie; Kumasaka, Mayuko; Debeir, Olivier; Letort, Véronique; Gallagher, Stuart J; Larue, Lionel

2013-01-01

Cell migration is a key biological process with a role in both physiological and pathological conditions. Locomotion of cells during embryonic development is essential for their correct positioning in the organism; immune cells have to migrate and circulate in response to injury. Failure of cells to migrate or an inappropriate acquisition of migratory capacities can result in severe defects such as altered pigmentation, skull and limb abnormalities during development, and defective wound repair, immunosuppression or tumor dissemination. The ability to accurately analyze and quantify cell migration is important for our understanding of development, homeostasis and disease. In vitro cell tracking experiments, using primary or established cell cultures, are often used to study migration as cells can quickly and easily be genetically or chemically manipulated. Images of the cells are acquired at regular time intervals over several hours using microscopes equipped with CCD camera. The locations (x,y,t) of each cell on the recorded sequence of frames then need to be tracked. Manual computer-assisted tracking is the traditional method for analyzing the migratory behavior of cells. However, this processing is extremely tedious and time-consuming. Most existing tracking algorithms require experience in programming languages that are unfamiliar to most biologists. We therefore developed an automated cell tracking program, written in Java, which uses a mean-shift algorithm and ImageJ as a library. iTrack4U is a user-friendly software. Compared to manual tracking, it saves considerable amount of time to generate and analyze the variables characterizing cell migration, since they are automatically computed with iTrack4U. Another major interest of iTrack4U is the standardization and the lack of inter-experimenter differences. Finally, iTrack4U is adapted for phase contrast and fluorescent cells.

Automated cell tracking and analysis in phase-contrast videos (iTrack4U: development of Java software based on combined mean-shift processes.

Directory of Open Access Journals (Sweden)

Fabrice P Cordelières

Full Text Available Cell migration is a key biological process with a role in both physiological and pathological conditions. Locomotion of cells during embryonic development is essential for their correct positioning in the organism; immune cells have to migrate and circulate in response to injury. Failure of cells to migrate or an inappropriate acquisition of migratory capacities can result in severe defects such as altered pigmentation, skull and limb abnormalities during development, and defective wound repair, immunosuppression or tumor dissemination. The ability to accurately analyze and quantify cell migration is important for our understanding of development, homeostasis and disease. In vitro cell tracking experiments, using primary or established cell cultures, are often used to study migration as cells can quickly and easily be genetically or chemically manipulated. Images of the cells are acquired at regular time intervals over several hours using microscopes equipped with CCD camera. The locations (x,y,t of each cell on the recorded sequence of frames then need to be tracked. Manual computer-assisted tracking is the traditional method for analyzing the migratory behavior of cells. However, this processing is extremely tedious and time-consuming. Most existing tracking algorithms require experience in programming languages that are unfamiliar to most biologists. We therefore developed an automated cell tracking program, written in Java, which uses a mean-shift algorithm and ImageJ as a library. iTrack4U is a user-friendly software. Compared to manual tracking, it saves considerable amount of time to generate and analyze the variables characterizing cell migration, since they are automatically computed with iTrack4U. Another major interest of iTrack4U is the standardization and the lack of inter-experimenter differences. Finally, iTrack4U is adapted for phase contrast and fluorescent cells.

The structure and magnetic moment distribution in the antiferromagnetic phase of U sub 1 sub 4 Au sub 5 sub 1

CERN Document Server

Brown, P J; Neumann, K U; Smith, J G; Ziebeck, K R A

1997-01-01

The antiferromagnetic structure of the intermetallic compound U sub 1 sub 4 Au sub 5 sub 1 has been determined from neutron polarimetric measurements and refined by combining these data with integrated intensity measurements. The structure was found to be non-collinear with the U moments confined to the a-b plane. The moments of U atoms in each of the two sets of sixfold sites are arranged hexagonally with rotations of 60 deg. between them and the two sets are rotated with respect to one another by 50 deg. The third (twofold) set of U atoms has no ordered moment. These conclusions are in disagreement with a previous determination of the structure from powder data which gave a collinear structure with moments parallel to the c axis. Magnetization measurements made on single crystals in the temperature range 300-2 K can be understood in terms of a transition to a non-collinear easy plane antiferromagnetic structure stable below 22 K. Polarized neutron measurements have been used to determine the contribution of...

Analysis list: sem-4 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available sem-4 Larvae + ce10 http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/target/sem-4.1....tsv http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/target/sem-4.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/target/sem...-4.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/colo/sem-4.Larvae.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/colo/Larvae.gml ...

U-series dating using thermal ionisation mass spectrometry (TIMS)

International Nuclear Information System (INIS)

McCulloch, M.T.

1999-01-01

U-series dating is based on the decay of the two long-lived isotopes 238 U(τ 1/2 =4.47 x 10 9 years) and 235 U (τ 1/2 0.7 x 10 9 years). 238 U and its intermediate daughter isotopes 234 U (τ 1/2 = 245.4 ka) and 230 Th (τ 1/2 = 75.4 ka) have been the main focus of recently developed mass spectrometric techniques (Edwards et al., 1987) while the other less frequently used decay chain is based on the decay 235 U to 231 Pa (τ 1/2 = 32.8 ka). Both the 238 U and 235 U decay chains terminate at the stable isotopes 206 Pb and 207 Pb respectively. Thermal ionization mass spectrometry (TIMS) has a number of inherent advantages, mainly the ability to measure isotopic ratios at high precision on relatively small samples. In spite of these now obvious advantages, it is only since the mid-1980's when Chen et al., (1986) made the first precise measurements of 234 U and 232 Th in seawater followed by Edwards et al., (1987) who made combined 234 U- 230 Th measurements, was the full potential of mass spectrometric methods first realised. Several examples are given to illustrate various aspects of TIMS U-series

Comparison of U-Pu-Mo, U-Pu-Nb, U-Pu-Ti and U-Pu-Zr alloys; Comparaison des alliages U-Pu-Mo, U-Pu-Nb, U-Pu-Ti, U-Pu-Zr

Energy Technology Data Exchange (ETDEWEB)

Boucher, R; Barthelemy, P [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1964-07-01

The data concerning the U-Pu, U-Pu-Mo and U-Pu-Nb are recalled. The results obtained with U-Pu-Ti and U-Pu-Zr alloys containing 15-20 per cent Pu and 10 wt. per cent ternary element are reported. The transformation temperatures, the expansion coefficients, the nature of phases, the thermal cycling behaviour have been determined. A list of the principal properties of these different alloys is presented and the possibilities of their use as fast reactor's fuel element are considered. The U-Pu-Ti alloys seem to be quite promising: easiness of fabrication, large thermal stability, excellent behaviour in air, small quantity of zeta phase, temperature of solidus superior to 1100 deg. C. (authors) [French] On rappelle brievement les connaissances acquises sur les alliages U-Pu, U-Pu-Mo et U-Pu-Nb. On presente les resultats obtenus avec les alliages U-Pu-Ti et U-Pu-Zr pour des teneurs de 15 a 20 pour cent de plutonium et 10 pour cent en poids d'element ternaire. On a determine les temperatures de transformation, les coefficients de dilatation, la nature des phases, la conductibilite thermique a 20 deg. C, la tenue au cyclage thermique et diverses autres proprietes. Un tableau resume les principales proprietes des divers alliages. On considere les possibilites d'emploi de ces alliages comme combustibles de reacteur rapide. Les alliages U-Pu-Ti paraissent particulierement interessants: facilite d'elaboration, stabilite thermique etendue, tenue dans l'air excellente, faible quantite de la phase U-Pu zeta, temperature de fusion commencante superieure a 1100 deg. C. (auteurs)

Analysis list: Irf4 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Irf4 Blood + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Irf4.1.tsv h...ttp://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Irf4.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Irf4....10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Irf4.Blood.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Blood.gml ...

Azimuthal Anisotropy in U +U and Au +Au Collisions at RHIC

Science.gov (United States)

Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Banerjee, A.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Bouchet, J.; Brandin, A. V.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Caines, H.; Calderón de la Barca Sánchez, M.; Campbell, J. M.; Cebra, D.; Cervantes, M. C.; Chakaberia, I.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, J. H.; Chen, X.; Cheng, J.; Cherney, M.; Christie, W.; Contin, G.; Crawford, H. J.; Das, S.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; di Ruzza, B.; Didenko, L.; Dilks, C.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Eppley, G.; Esha, R.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Federic, P.; Fedorisin, J.; Feng, Z.; Filip, P.; Fisyak, Y.; Flores, C. E.; Fulek, L.; Gagliardi, C. A.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, S.; Gupta, A.; Guryn, W.; Hamad, A.; Hamed, A.; Haque, R.; Harris, J. W.; He, L.; Heppelmann, S.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, H. Z.; Huang, B.; Huang, X.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jang, H.; Jiang, K.; Judd, E. G.; Kabana, S.; Kalinkin, D.; Kang, K.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Khan, Z. H.; Kikola, D. P.; Kisel, I.; Kisiel, A.; Koetke, D. D.; Kollegger, T.; Kosarzewski, L. K.; Kotchenda, L.; Kraishan, A. F.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Kycia, R. A.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Li, W.; Li, Y.; Li, C.; Li, Z. M.; Li, X.; Li, X.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, L.; Ma, R.; Ma, Y. G.; Ma, G. L.; Magdy, N.; Majka, R.; Manion, A.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; Meehan, K.; Minaev, N. G.; Mioduszewski, S.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Okorokov, V.; Olvitt, D. L.; Page, B. S.; Pak, R.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlik, B.; Pei, H.; Perkins, C.; Peterson, A.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Poniatowska, K.; Porter, J.; Posik, M.; Poskanzer, A. M.; Pruthi, N. K.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, S.; Raniwala, R.; Ray, R. L.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandweiss, J.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, W. B.; Schmitz, N.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shanmuganathan, P. V.; Shao, M.; Sharma, B.; Sharma, M. K.; Shen, W. Q.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Sikora, R.; Simko, M.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Song, L.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stepanov, M.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Summa, B. J.; Sun, X.; Sun, X. M.; Sun, Z.; Sun, Y.; Surrow, B.; Svirida, D. N.; Szelezniak, M. A.; Tang, Z.; Tang, A. H.; Tarnowsky, T.; Tawfik, A. N.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Tripathy, S. K.; Trzeciak, B. A.; Tsai, O. D.; Ullrich, T.; Underwood, D. G.; Upsal, I.; Van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Varma, R.; Vasiliev, A. N.; Vertesi, R.; Videbaek, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wang, F.; Wang, Y.; Wang, H.; Wang, J. S.; Wang, Y.; Wang, G.; Webb, G.; Webb, J. C.; Wen, L.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, Y. F.; Xu, N.; Xu, Z.; Xu, Q. H.; Xu, H.; Yang, Y.; Yang, Y.; Yang, C.; Yang, S.; Yang, Q.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I.-K.; Yu, N.; Zbroszczyk, H.; Zha, W.; Zhang, X. P.; Zhang, J. B.; Zhang, J.; Zhang, Z.; Zhang, S.; Zhang, Y.; Zhang, J. L.; Zhao, F.; Zhao, J.; Zhong, C.; Zhou, L.; Zhu, X.; Zoulkarneeva, Y.; Zyzak, M.; STAR Collaboration

2015-11-01

Collisions between prolate uranium nuclei are used to study how particle production and azimuthal anisotropies depend on initial geometry in heavy-ion collisions. We report the two- and four-particle cumulants, v2{2 } and v2{4 }, for charged hadrons from U +U collisions at √{sNN }=193 GeV and Au +Au collisions at √{sNN}=200 GeV . Nearly fully overlapping collisions are selected based on the energy deposited by spectators in zero degree calorimeters (ZDCs). Within this sample, the observed dependence of v2{2 } on multiplicity demonstrates that ZDC information combined with multiplicity can preferentially select different overlap configurations in U +U collisions. We also show that v2 vs multiplicity can be better described by models, such as gluon saturation or quark participant models, that eliminate the dependence of the multiplicity on the number of binary nucleon-nucleon collisions.

Azimuthal Anisotropy in U+U and Au+Au Collisions at RHIC.

Science.gov (United States)

Adamczyk, L; Adkins, J K; Agakishiev, G; Aggarwal, M M; Ahammed, Z; Alekseev, I; Alford, J; Aparin, A; Arkhipkin, D; Aschenauer, E C; Averichev, G S; Banerjee, A; Bellwied, R; Bhasin, A; Bhati, A K; Bhattarai, P; Bielcik, J; Bielcikova, J; Bland, L C; Bordyuzhin, I G; Bouchet, J; Brandin, A V; Bunzarov, I; Burton, T P; Butterworth, J; Caines, H; Calderón de la Barca Sánchez, M; Campbell, J M; Cebra, D; Cervantes, M C; Chakaberia, I; Chaloupka, P; Chang, Z; Chattopadhyay, S; Chen, J H; Chen, X; Cheng, J; Cherney, M; Christie, W; Contin, G; Crawford, H J; Das, S; De Silva, L C; Debbe, R R; Dedovich, T G; Deng, J; Derevschikov, A A; di Ruzza, B; Didenko, L; Dilks, C; Dong, X; Drachenberg, J L; Draper, J E; Du, C M; Dunkelberger, L E; Dunlop, J C; Efimov, L G; Engelage, J; Eppley, G; Esha, R; Evdokimov, O; Eyser, O; Fatemi, R; Fazio, S; Federic, P; Fedorisin, J; Feng, Z; Filip, P; Fisyak, Y; Flores, C E; Fulek, L; Gagliardi, C A; Garand, D; Geurts, F; Gibson, A; Girard, M; Greiner, L; Grosnick, D; Gunarathne, D S; Guo, Y; Gupta, S; Gupta, A; Guryn, W; Hamad, A; Hamed, A; Haque, R; Harris, J W; He, L; Heppelmann, S; Heppelmann, S; Hirsch, A; Hoffmann, G W; Hofman, D J; Horvat, S; Huang, H Z; Huang, B; Huang, X; Huck, P; Humanic, T J; Igo, G; Jacobs, W W; Jang, H; Jiang, K; Judd, E G; Kabana, S; Kalinkin, D; Kang, K; Kauder, K; Ke, H W; Keane, D; Kechechyan, A; Khan, Z H; Kikola, D P; Kisel, I; Kisiel, A; Koetke, D D; Kollegger, T; Kosarzewski, L K; Kotchenda, L; Kraishan, A F; Kravtsov, P; Krueger, K; Kulakov, I; Kumar, L; Kycia, R A; Lamont, M A C; Landgraf, J M; Landry, K D; Lauret, J; Lebedev, A; Lednicky, R; Lee, J H; Li, W; Li, Y; Li, C; Li, Z M; Li, X; Li, X; Lisa, M A; Liu, F; Ljubicic, T; Llope, W J; Lomnitz, M; Longacre, R S; Luo, X; Ma, L; Ma, R; Ma, Y G; Ma, G L; Magdy, N; Majka, R; Manion, A; Margetis, S; Markert, C; Masui, H; Matis, H S; McDonald, D; Meehan, K; Minaev, N G; Mioduszewski, S; Mohanty, B; Mondal, M M; Morozov, D A; Mustafa, M K; Nandi, B K; Nasim, Md; Nayak, T K; Nigmatkulov, G; Nogach, L V; Noh, S Y; Novak, J; Nurushev, S B; Odyniec, G; Ogawa, A; Oh, K; Okorokov, V; Olvitt, D L; Page, B S; Pak, R; Pan, Y X; Pandit, Y; Panebratsev, Y; Pawlik, B; Pei, H; Perkins, C; Peterson, A; Pile, P; Planinic, M; Pluta, J; Poljak, N; Poniatowska, K; Porter, J; Posik, M; Poskanzer, A M; Pruthi, N K; Putschke, J; Qiu, H; Quintero, A; Ramachandran, S; Raniwala, S; Raniwala, R; Ray, R L; Ritter, H G; Roberts, J B; Rogachevskiy, O V; Romero, J L; Roy, A; Ruan, L; Rusnak, J; Rusnakova, O; Sahoo, N R; Sahu, P K; Sakrejda, I; Salur, S; Sandweiss, J; Sarkar, A; Schambach, J; Scharenberg, R P; Schmah, A M; Schmidke, W B; Schmitz, N; Seger, J; Seyboth, P; Shah, N; Shahaliev, E; Shanmuganathan, P V; Shao, M; Sharma, B; Sharma, M K; Shen, W Q; Shi, S S; Shou, Q Y; Sichtermann, E P; Sikora, R; Simko, M; Skoby, M J; Smirnov, D; Smirnov, N; Song, L; Sorensen, P; Spinka, H M; Srivastava, B; Stanislaus, T D S; Stepanov, M; Stock, R; Strikhanov, M; Stringfellow, B; Sumbera, M; Summa, B J; Sun, X; Sun, X M; Sun, Z; Sun, Y; Surrow, B; Svirida, D N; Szelezniak, M A; Tang, Z; Tang, A H; Tarnowsky, T; Tawfik, A N; Thomas, J H; Timmins, A R; Tlusty, D; Tokarev, M; Trentalange, S; Tribble, R E; Tribedy, P; Tripathy, S K; Trzeciak, B A; Tsai, O D; Ullrich, T; Underwood, D G; Upsal, I; Van Buren, G; van Nieuwenhuizen, G; Vandenbroucke, M; Varma, R; Vasiliev, A N; Vertesi, R; Videbaek, F; Viyogi, Y P; Vokal, S; Voloshin, S A; Vossen, A; Wang, F; Wang, Y; Wang, H; Wang, J S; Wang, Y; Wang, G; Webb, G; Webb, J C; Wen, L; Westfall, G D; Wieman, H; Wissink, S W; Witt, R; Wu, Y F; Xiao, Z; Xie, W; Xin, K; Xu, Y F; Xu, N; Xu, Z; Xu, Q H; Xu, H; Yang, Y; Yang, Y; Yang, C; Yang, S; Yang, Q; Ye, Z; Yepes, P; Yi, L; Yip, K; Yoo, I-K; Yu, N; Zbroszczyk, H; Zha, W; Zhang, X P; Zhang, J B; Zhang, J; Zhang, Z; Zhang, S; Zhang, Y; Zhang, J L; Zhao, F; Zhao, J; Zhong, C; Zhou, L; Zhu, X; Zoulkarneeva, Y; Zyzak, M

2015-11-27

Collisions between prolate uranium nuclei are used to study how particle production and azimuthal anisotropies depend on initial geometry in heavy-ion collisions. We report the two- and four-particle cumulants, v_{2}{2} and v_{2}{4}, for charged hadrons from U+U collisions at sqrt[s_{NN}]=193  GeV and Au+Au collisions at sqrt[s_{NN}]=200  GeV. Nearly fully overlapping collisions are selected based on the energy deposited by spectators in zero degree calorimeters (ZDCs). Within this sample, the observed dependence of v_{2}{2} on multiplicity demonstrates that ZDC information combined with multiplicity can preferentially select different overlap configurations in U+U collisions. We also show that v_{2} vs multiplicity can be better described by models, such as gluon saturation or quark participant models, that eliminate the dependence of the multiplicity on the number of binary nucleon-nucleon collisions.

Dicty_cDB: Contig-U15462-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U15462-1 no gap 546 4 3384206 3383661 MINUS 2 2 U15462 0 0 2 0 0 0 0 0 0 0 0 0 0 0 Show Contig...-U15462-1 Contig ID Contig-U15462-1 Contig update 2004. 6.11 Contig sequence >Contig-U15462-1 (Contig...-U15462-1Q) /CSM_Contig/Contig-U15462-1Q.Seq.d CTTTAGATTGGGGNTCAAGAAAAATATTGAAGTATTTGGTGGTGATAAGA...ATTCGATTCACTATCTTATA Gap no gap Contig length 546 Chromosome number (1..6, M) 4 Chromosome length 5430582 St...VMKLGFEVKDLITNDPKCDLFDSLS Y own update 2004. 6.23 Homology vs CSM-cDNA Query= Contig-U15462-1 (Contig

A Stable U Isotopic Perspective on the U Budget and Global Extent of Modern Anoxia in the Ocean.

Science.gov (United States)

Tissot, F.; Dauphas, N.

2015-12-01

Isotopic fractionation between U4+ and U6+makes U stable isotopes potential tracers of global paleoredox conditions. In this work [1], we put the U-proxy up to a test against a highly constrained system: the modern ocean. We measured a large number of seawater samples from geographically diverse locations and found that the open ocean has a homogenous isotopic composition at δ238USW= -0.392 ± 0.005 ‰ (rel. to CRM-112a). From our measurement of rock samples (n=64) and compilations of literature data (n=380), we then estimated the U isotopic compositions of the various reservoirs involved in the modern oceanic U budget, as well as the fractionation factors associated with U incorporation into those reservoirs. Using a steady-state model, we compared the isotopic composition of the seawater predicted by the four most recent U oceanic budgets [2-5] to the modern seawater value we measured. Three of these budgets [2-4] predict a seawater isotopic composition in very good agreement with the observed δ238USW, which strengthens our confidence in the isotopic fractionation factors associated with each deposition environment and the fact that U is at steady-state in the modern ocean. The U oceanic budget of Henderson and Anderson (2003) does not reproduce the observed seawater composition because the U flux to anoxic/euxinic sediments relative to the total U flux out of the ocean is high in their model, which our analysis shows cannot be correct. The U isotopic composition of seawater is used to constrain the extent of anoxia in the modern ocean (% of seafloor covered by anoxic/euxinic sediments), which is 0.21 ± 0.09 %. This work demonstrates that stable isotopes of U can indeed trace the extent of anoxia in the modern global ocean, thereby validating the application of U isotope measurements to paleoredox reconstructions. Based on the above work, we will present the best estimate of the modern oceanic U budget. [1] Tissot F.L.H., Dauphas N. (2015) Geochim Cosmochim

Synthesis of (+)-(3R)-3-(4-fluorophenylsulfonamido)-1,2,3,4-tetrahydro-9-[5,6,7,8,12,13-u-{sup 14}C]carbazoleppropanoic acid, [{sup 14}C]BAY u 3405

Energy Technology Data Exchange (ETDEWEB)

Radtke, M; Boberg, M; Pleiss, U [Inst. of Pharmacokinetics, Bayer AG, Wuppertal (Germany); Rosentreter, U [Pharma Production, Bayer AG. Wuppertal (Germany)

1994-12-01

The title compound [{sup 14}C]BAY u 3405 (1) was synthesized as part of 8-step sequence. Starting from [U-{sup 14}C]aniline hydrogensulfate the final product 1 was obtained with a specific activity of 741 MBq/mmol (20 mCi/mmol) and a radiochemical purity of > 98 % in an overall yield of 6 and 10 % depending on the method. (author).

High Beta Steady State Research and Future Directions on JT-60U and JFT-2M

Science.gov (United States)

Ishida, Shinichi

2003-10-01

JT-60U and JFT-2M research is focused on high beta steady state operation towards economically and environmentally attractive reactors. In JT-60U, a high-βp H-mode plasma was sustained with βN 2.7 for 7.4 s in which neoclassical tearing modes (NTMs) limited the attainable β_N. Real-time tracking NTM stabilization system using ECCD demonstrated complete suppression of NTM leading to recovery of βN before onset of NTM. Performance in a fully non-inductive H-mode plasma was improved up to n_i(0) τE T_i(0) = 3.1 x 10^20 keV s m-3 using N-NBCD with βN 2.4, HH_y,2=1.2 and bootstrap fraction f_BS 0.5. ECH experiments extended the confinement enhancement for dominantly electron heated reversed shear plasmas up to HH_y,2 2 at T_e/Ti 1.25. A world record ECCD efficiency, 4.2 x 10^18 A/W/m^2, was achieved at Te 23 keV with a highly localized central current density. Innovative initiation and current build-up without center solenoid currents were established by LHCD/ECH and bootstrap current up to f_BS 0.9. In JFT-2M, the inside of the vacuum vessel wall was fully covered with low-activation ferritic steel plates to investigate their use in plasmas near fusion conditions. High βN plasmas were produced up to βN = 3.3 with an internal transport barrier (ITB) and a steady H-mode edge. A new H-mode regime with steady high recycling (HRS) and an ITB was exploited leading to βN H_89P 6.2 at n_e/nG 0.7. In 2003, JT-60U will be able to operate for the duration up to 65 s at 1 MA/2.7 T and the heating/current-drive duration up to 30 s at 17 MW to prolong high-βN and/or high-f_BS discharges with feedback controls. JFT-2M is planning to implement wall stabilization experiments in 2004 to pursue plasmas above the ideal no-wall limit using a ferritic wall. The modification of JT-60 to a fully superconducting tokamak is under discussion to explore high-β steady state operation in collision-less plasmas well above no-wall limit with ferritic wall in a steady state.

EVOLUTION OF THE CROSS-CORRELATION AND TIME LAG OF 4U 1735-44 ALONG THE BRANCHES

International Nuclear Information System (INIS)

Lei Yajuan; Zhang Haotong; Zhang Chengmin; Yuan Hailong; Dong Yiqiao; Zhao Yongheng; Zhang Yanxia; Qu Jinlu; Song Liming; Wang Dehua; Yin Hongxing

2013-01-01

We analyze the cross-correlation function between the soft and hard X-rays of atoll source 4U 1735-44 with RXTE data, and find anti-correlated soft and hard time lags of about a hecto-second. In the island state, the observations do not show any obvious correlations, and most observations of the banana branch show a positive correlation. However, anti-correlations are detected in the upper banana branch. These results are different from those of Z-sources (Cyg X-2, GX 5-1), where anti-correlations are detected in the horizontal branch and upper normal branch. In this case, the lag timescales of both this atoll and Z-sources are found to be similar, at a magnitude of several tens to hundreds of seconds. As a comparison, it is noted that anti-correlated lags lasting thousands of seconds have been reported from several black hole candidates in their intermediate states. In addition, for an observation containing four segments that show positive or anti-correlation, we analyze the spectral evolution with the hybrid model. In the observation, the anti-correlation is detected at the highest flux. The fitting results show that the Comptonized component is not the lowest at the highest flux, which suggests that the anti-correlation corresponds to the transition between the soft and hard states. Finally, we compare the corresponding results of atoll source 4U 1735-44 with those observed in Z-sources and black hole candidates, and the possible origins of the anti-correlated time lags are discussed

EVOLUTION OF THE CROSS-CORRELATION AND TIME LAG OF 4U 1735-44 ALONG THE BRANCHES

Energy Technology Data Exchange (ETDEWEB)

Lei Yajuan; Zhang Haotong; Zhang Chengmin; Yuan Hailong; Dong Yiqiao; Zhao Yongheng; Zhang Yanxia [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Qu Jinlu; Song Liming [Particle Astrophysics Center, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Wang Dehua [Astronomy Department, Beijing Normal University, Beijing 100875 (China); Yin Hongxing, E-mail: leiyjcwmy@163.com [School of Space Science and Physics, Shandong University, Weihai 264209 (China)

2013-09-15

We analyze the cross-correlation function between the soft and hard X-rays of atoll source 4U 1735-44 with RXTE data, and find anti-correlated soft and hard time lags of about a hecto-second. In the island state, the observations do not show any obvious correlations, and most observations of the banana branch show a positive correlation. However, anti-correlations are detected in the upper banana branch. These results are different from those of Z-sources (Cyg X-2, GX 5-1), where anti-correlations are detected in the horizontal branch and upper normal branch. In this case, the lag timescales of both this atoll and Z-sources are found to be similar, at a magnitude of several tens to hundreds of seconds. As a comparison, it is noted that anti-correlated lags lasting thousands of seconds have been reported from several black hole candidates in their intermediate states. In addition, for an observation containing four segments that show positive or anti-correlation, we analyze the spectral evolution with the hybrid model. In the observation, the anti-correlation is detected at the highest flux. The fitting results show that the Comptonized component is not the lowest at the highest flux, which suggests that the anti-correlation corresponds to the transition between the soft and hard states. Finally, we compare the corresponding results of atoll source 4U 1735-44 with those observed in Z-sources and black hole candidates, and the possible origins of the anti-correlated time lags are discussed.

Spectral evolution of the Atoll source 4U 1728-34 with RXTE and INTEGRAL: evidence for hard X-ray tail

NARCIS (Netherlands)

Tarana, A.; Belloni, T.; Bazzano, A.; Homan, J.; Méndez, M.; Ubertini, P.; Comastri, A.; Angelini, L.; Cappi, M.

We report the temporal and spectral results on the INTEGRAL and RXTE 2006-2007 observation campaign of the Atoll source 4U 1728-34 (GX 354-0). The source shows, more than once, spectral evolution as revealed by the hardness intensity diagram. The soft state is well described by a Comptonization with

Short-term X-ray variability of the globular cluster source 4U 1820 - 30 (NGC 6624)

Science.gov (United States)

Stella, L.; Kahn, S. M.; Grindlay, J. E.

1984-01-01

Analytical techniques for improved identification of the temporal and spectral variability properties of globular cluster and galactic bulge X-ray sources are described in terms of their application to a large set of observations of the source 4U 1820 - 30 in the globular cluster NGC 6624. The autocorrelation function, cross-correlations, time skewness function, erratic periodicities, and pulse trains are examined. The results are discussed in terms of current models with particular emphasis on recent accretion disk models. It is concluded that the analyzed observations provide the first evidence for shot-noise variability in a globular cluster X-ray source.

Radio and X-Ray Observations of the 1998 Outburst of the Recurrent X-Ray Transient 4U 1630-47

Science.gov (United States)

Hjellming, R. M.; Rupen, M. P.; Mioduszewski, A. J.; Kuulkers, E.; McCollough, M.; Harmon, B. A.; Buxton, M.; Sood, R.; Tzioumis, A.; Rayner, D.; Dieters, S.; Durouchoux, P.

1999-03-01

We report radio (NRAO VLA and Australia Telescope Compact Array), soft X-ray (Rossi X-Ray Timing Explorer ASM), and hard X-ray (Compton Gamma Ray Observatory BATSE) observations of a 1998 outburst in the recurring X-ray transient 4U 1630-47, where radio emission was detected for the first time. The radio observations identify the position of 4U 1630-47 to within 1". Because the radio emission is optically thin with a spectral index of ~-0.8 during the rise, peak, and decay of the initial radio event, the emission is probably coming from an optically thin radio jet ejected over a period of time. The 20-100 keV emission first appeared 1998 January 28 (MJD 50841), the 2-12 keV emission first appeared 1998 February 3 (MJD 50847), and the first radio emission was detected 1998 February 12.6 (MJD 50856.6). The rise of the radio emission probably began about 1998 February 7 (MJD 50851) when the X-rays were in a very hard fluctuating-hardness state, just before changing to a softer, more stable hardness state.

Mucosal immunization with live attenuated Francisella novicida U112ΔiglB protects against pulmonary F. tularensis SCHU S4 in the Fischer 344 rat model.

Directory of Open Access Journals (Sweden)

Aimee L Signarovitz

Full Text Available The need for an efficacious vaccine against Francisella tularensis is a consequence of its low infectious dose and high mortality rate if left untreated. This study sought to characterize a live attenuated subspecies novicida-based vaccine strain (U112ΔiglB in an established second rodent model of pulmonary tularemia, namely the Fischer 344 rat using two distinct routes of vaccination (intratracheal [i.t.] and oral. Attenuation was verified by comparing replication of U112ΔiglB with wild type parental strain U112 in F344 primary alveolar macrophages. U112ΔiglB exhibited an LD(50>10(7 CFU compared to the wild type (LD(50 = 5 × 10(6 CFU i.t.. Immunization with 10(7 CFU U112ΔiglB by i.t. and oral routes induced antigen-specific IFN-γ and potent humoral responses both systemically (IgG2a>IgG1 in serum and at the site of mucosal vaccination (respiratory/intestinal compartment. Importantly, vaccination with U112ΔiglB by either i.t. or oral routes provided equivalent levels of protection (50% survival in F344 rats against a subsequent pulmonary challenge with ~25 LD(50 (1.25 × 10(4 CFU of the highly human virulent strain SCHU S4. Collectively, these results provide further evidence on the utility of a mucosal vaccination platform with a defined subsp. novicida U112ΔiglB vaccine strain in conferring protective immunity against pulmonary tularemia.

Search for Coulomb-induced multifragmentation in the reaction Gd+U at 36 MeV/u

International Nuclear Information System (INIS)

Bacri, C.O.; Squalli, M.; Borderie, B.; Frankland, J.D.; Parlog, M.; Rivet, M.F.; Tassan-Got, L.; Charvet, J.L.

1996-03-01

Coulomb-induced multifragmentation is looked for in the study of the system Gd+U at 36 MeV/u with the 4π INDRA detector. Events corresponding to fragment emission from a single source were selected in the system Gd+U using global variables. Different kinematical correlations between the emitted fragments are discussed. Comparisons with simulations are used to extract the shape of the system which decays by multifragmentation, and also to obtain quantitative information about possible expansion effects. (K.A.)

Dicty_cDB: Contig-U12682-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U12682-1 no gap 1408 4 4961739 4963050 PLUS 47 48 U12682 0 0 0 5 0 0 2 30 0 10 0 0 0 0 Show Contig...-U12682-1 Contig ID Contig-U12682-1 Contig update 2002.12.18 Contig sequence >Contig-U12682-1 (Contig...-U12682-1Q) /CSM_Contig/Contig-U12682-1Q.Seq.d AAACACATCATCCCGTTCGATCTGATAAGTAAATCGACCTCAGGCC...ATGA AACTACTG Gap no gap Contig length 1408 Chromosome number (1..6, M) 4 Chromosome length 5430582 Start po... kwniikwysyinwykswyn**fihsiklqwsy*qcke*si*yiir*ny own update 2004. 6.10 Homology vs CSM-cDNA Query= Contig

Proceedings fo the Seventeenth Annual Sea Turtle Symposium, 4-8 March 1997, Orlando, Florida, U.S.A.

OpenAIRE

Epperly, Sheryan P.; Braun, Joanne

1998-01-01

The 17th Annual Sea Turtle Symposium was held at the Delta Orlando Resort in Orlando, Florida U.S.A. from March 4-8, 1997. The symposium was hosted by Florida Atlantic University, Mote Marine Laboratory, University of Central Florida, University of Florida, Florida Atlantic University and the Comité Nacional para la Conservación y Protección de las Totugas Marinas. The 17th was the largest symposium to date. A total of 720 participants registered, including sea turtle biologists, stu...

Analysis list: Hnf4a [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Hnf4a Digestive tract,Embryo,Gonad,Kidney,Liver,Prostate + mm9 http://dbarchive.bio...sciencedbc.jp/kyushu-u/mm9/target/Hnf4a.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Hnf4a.5....tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Hnf4a.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Hnf4...a.Digestive_tract.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Hnf4...a.Embryo.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Hnf4a.Gonad.tsv,http://dbar

Characterization of the interaction layer in diffusion couples U-Mo-Zr/Al and U-Mo-Zr/Al-A356 at 550 C degrees; Caracterizacion de la zona de interaccion en pares de difusion a 550 grados C U-Mo-Zr/Al y U-Mo-Zr/Al-A356

Energy Technology Data Exchange (ETDEWEB)

Komar Varela, Carolina; Arico, Sergio; Mirandou, Marcela; Balart, Silvia; Gribaudo, Luis [Comision Nacional de Energia Atomica, General San Martin (Argentina). Dept. de Materiales; com, carolinakomar@gmail

2007-07-01

Out-of-pile diffusion experiments were performed between U-7 wt.% Mo-1 wt.% Zr and Al or Al A356 (7,1 wt.% Si) at 550 C degrees. In this work morphological characterization and phase identification on both interaction layers are presented. They were carried out by the use of different techniques: optical and scanning electron microscopy, X-ray diffraction and WDS microanalysis. In the interaction layer U-7 wt.% Mo-1 wt.% Zr/Al, the phases UAl{sub 3}, UAl{sub 4}, Al{sub 20}Mo{sub 2}U and Al{sub 43}Mo{sub 4}U{sub 6} were identified. Similar results in the interaction layer of the U-7 % Mo/Al at 580 C degrees were previously obtained. In the interaction layer U-7 wt.% Mo-1 wt.% Zr/Al A356, the phases U(Al,Si){sub 3} with 25 at.% Si and Si{sub 5}U{sub 3} were identified. This last phase, with a higher Si concentration, was identified with X-ray diffraction synchrotron radiation performed at the National Synchrotron Light Laboratory, Campinas, Brazil. (author) [Spanish] Se realizaron experiencias fuera de reactor en pares de difusion quimica U-7 % Mo-1 % Zr/Al y U-7 % Mo-1 % Zr/Al A356. En este trabajo se presentan los resultados de la caracterizacion morfologica e identificacion de fases presentes en la zona de interaccion que se forma al ser sometidos a un tratamiento isotermico de 1,5 h a 550 grados C. Las tecnicas utilizadas fueron: microscopia optica y electronica de barrido, difraccion de rayos X y microanalisis cuantitativo por sonda electronica. En la zona de interaccion correspondiente al par U-7 % Mo-1 % Zr/Al se identificaron las fases UAl{sub 3}, UAl{sub 4}, Al{sub 20}Mo{sub 2}U y Al{sub 43}Mo{sub 4}U{sub 6}. Estas cuatro fases fueron identificadas en pares U-7 % Mo/Al a 580 grados C en trabajos anteriores. En la zona de interaccion correspondiente al par U-7 % Mo-1 % Zr/Al A356 se identificaron las fases U(Al,Si){sub 3} (con una concentracion de 25 %at.Si) y Si{sub 5}U{sub 3}. Este compuesto rico en Si solo pudo ser identificado mediante la utilizacion de

Low silicon U(Al,Si)3 stabilization by Zr addition

International Nuclear Information System (INIS)

Pizarro, L.M.; Alonso, P.R.; Rubiolo, G.H.

2009-01-01

Previous knowledge states that (U,Zr)Al 3 and U(Al,Si) 3 phases with Zr and Si content higher than 6 at.% (7.7 wt%) and 4 at.% (1.4 wt%), respectively, does not partially transform to UAl 4 at 600 o C. In this work, four alloys within the quaternary system U-Al-Si-Zr were made with a fixed nominal 0.18 at.% (0.1 wt%) Si content in order to assess the synergetic effect of both Zr and Si alloying elements to the thermodynamic stability of the (U,Zr)(Al,Si) 3 phase. Heat treatments at 600 deg. C were undertaken and samples were analyzed by means of XRD, EPMA and EDS techniques. A remarkable conclusion is that addition of 0.3 at.% Si in the (U,Zr)(Al,Si) 3 phase reduces in 2.7 at.% the necessary Zr content to inhibit its transformation to U(Al,Si) 4 .

Single crystal structures and theoretical calculations of uranium endohedral metallofullerenes (U@C2n , 2n = 74, 82) show cage isomer dependent oxidation states for U.

Science.gov (United States)

Cai, Wenting; Morales-Martínez, Roser; Zhang, Xingxing; Najera, Daniel; Romero, Elkin L; Metta-Magaña, Alejandro; Rodríguez-Fortea, Antonio; Fortier, Skye; Chen, Ning; Poblet, Josep M; Echegoyen, Luis

2017-08-01

Charge transfer is a general phenomenon observed for all endohedral mono-metallofullerenes. Since the detection of the first endohedral metallofullerene (EMF), La@C 82 , in 1991, it has always been observed that the oxidation state of a given encapsulated metal is always the same, regardless of the cage size. No crystallographic data exist for any early actinide endohedrals and little is known about the oxidation states for the few compounds that have been reported. Here we report the X-ray structures of three uranium metallofullerenes, U@ D 3h -C 74 , U@ C 2 (5)-C 82 and U@ C 2v (9)-C 82 , and provide theoretical evidence for cage isomer dependent charge transfer states for U. Results from DFT calculations show that U@ D 3h -C 74 and U@ C 2 (5)-C 82 have tetravalent electronic configurations corresponding to U 4+ @ D 3h -C 74 4- and U 4+ @ C 2 (5)-C 82 4- . Surprisingly, the isomeric U@ C 2v (9)-C 82 has a trivalent electronic configuration corresponding to U 3+ @ C 2v (9)-C 82 3- . These are the first X-ray crystallographic structures of uranium EMFs and this is first observation of metal oxidation state dependence on carbon cage isomerism for mono-EMFs.

Prime Contractors with Awards over $25,000 by Name, Location, and Contract Number. Part 7 (Technology Systems Inc, Wiscasset, Maine -- Zymark Corporation, Hopkinton, Massachusetts), FY1991

Science.gov (United States)

1991-01-01

z V3 3z I .0J 0(. to0 0 ~ ml cci 0< ix F 3. l4 -I XI- 8 33 0 0 02~~ t; . 4L C0 3 w- = uc3 U (nl 3 C: go 0~~~ 3 8 t)0 0 0 C.)39. U 0 u3 F3 6i6t I -4 4...w cc~~- (n CI9- £. 4 1 6: 2) 2 0 - 1. w 9. W 423 u U .. ) w 0 ~ 4 acca CiC d x HH ul 1-4 H 1-4 HH OUR t- OD- =-4 m~ w ODI (’ S 000 D n01 0 IOD 0000 N...4W 0 F3 U9H -W) H .4. 0 m220 = C4 ix I C, gal 4 22 0~ 0 Ow. 0W". 0 ) U) 02 0 00 0 4 4 E .4 .4 w M 8 n2 0 0202402-02 蓤. 0. 2 2 .40 0 0 w Ld =) 8. Ca

The fission cross sections of /sup 230/Th, /sup 232/Th, /sup 233/U, /sup 234/U, /sup 236/U, /sup 238/U, /sup 237/Np, /sup 239/Pu and /sup 242/Pu relative /sup 235/U at 14. 74 MeV neutron energy

Energy Technology Data Exchange (ETDEWEB)

Meadows, J.W.

1986-12-01

The measurement of the fission cross section ratios of nine isotopes relative to /sup 235/U at an average neutron energy of 14.74 MeV is described with particular attention to the determination of corrections and to sources of error. The results are compared to ENDF/B-V and to other measurements of the past decade. The ratio of the neutron induced fission cross section for these isotopes to the fission cross section for /sup 235/U are: /sup 230/Th - 0.290 +- 1.9%; /sup 232/Th - 0.191 +- 1.9%; /sup 233/U - 1.132 +- 0.7%; /sup 234/U - 0.998 +- 1.0%; /sup 236/U - 0.791 +- 1.1%; /sup 238/U - 0.587 +- 1.1%; /sup 237/Np - 1.060 +- 1.4%; /sup 239/Pu - 1.152 +- 1.1%; /sup 242/Pu - 0.967 +- 1.0%. 40 refs., 11 tabs., 9 figs.

Study of physical, chemical and electronic properties of binaries and ternaries uranium compounds in the U-Si-B and U-Pt-Si systems

International Nuclear Information System (INIS)

Brisset, Nicolas

2016-01-01

Two main research axes were defined for this Ph-D work: (i) studying the effect of light elements (B, C) on the stability of U-Si compounds, and (ii) identifying and physically characterizing new phases in the U-Pt-Si system. Minor additions of carbon and boron in U-Si samples revealed that the formation of U 5 Si 4 would be correlated to the presence of these light elements, questioning its existence in the U-Si system. To evaluate the boron potential as a stimulant for non-metallic light elements of the second period (C, N, O), the isothermal section of the ternary phase diagram U-Si-B has been drawn at 927 C, disclosing solid equilibrium mainly between the UB and U-Si binary axes and the existence of the novel compound U 20 Si 16 B 3 , isostructural to the carbon equivalent one. These results suggest a specific behavior for a given light element on the U-Si phase relations. The isothermal section at 900 C of the U-Pt-Si ternary system was experimentally determined, leading to the discovery of 14 new phases, among which U 3 Pt 4 Si 6 , U 3 Pt 6 Si 4 and U 3 Pt 7 Si crystallized in their own structural type. As a prerequisite for this study, the phase relations in the U-Pt binary phase diagram were re-examined for the composition range 30 at.% and 70 at.% Pt, leading to a new assessment of the phase diagram which comprises the new U 3 Pt 4 compound. The temperature of the transformations has been measured by DTA. By coupling our experimental results to the literature data, a modeling of the phase diagram by the Calphad method was performed. Physical characterizations of the new U 3 Pt 4 compound revealed a moderate heavy fermion behavior, with ferromagnetic ordering below Tc = 7(1) K. As a side project, a study of the U 3 TGe 5 family with the anti-Hf 5 CuSn 3 structural type lead to the discovery of nine new compounds for T = V, Cr, Mn, Zr, Nb, Mo, Hf, Ta and W in addition to the previously reported U 3 TiGe 5 . Their magnetic and electronic properties were

U-series dating using thermal ionisation mass spectrometry (TIMS)

Energy Technology Data Exchange (ETDEWEB)

McCulloch, M.T. [Australian National University, Canberra, ACT (Australia). Research School of Earth Science

1999-11-01

U-series dating is based on the decay of the two long-lived isotopes{sup 238}U({tau}{sub 1/2}=4.47 x 10{sup 9} years) and {sup 235}U ({tau}{sub 1/2} 0.7 x 10{sup 9} years). {sup 238}U and its intermediate daughter isotopes {sup 234}U ({tau}{sub 1/2} = 245.4 ka) and {sup 230}Th ({tau}{sub 1/2} = 75.4 ka) have been the main focus of recently developed mass spectrometric techniques (Edwards et al., 1987) while the other less frequently used decay chain is based on the decay {sup 235}U to {sup 231}Pa ({tau}{sub 1/2} = 32.8 ka). Both the {sup 238}U and {sup 235}U decay chains terminate at the stable isotopes {sup 206}Pb and {sup 207}Pb respectively. Thermal ionization mass spectrometry (TIMS) has a number of inherent advantages, mainly the ability to measure isotopic ratios at high precision on relatively small samples. In spite of these now obvious advantages, it is only since the mid-1980`s when Chen et al., (1986) made the first precise measurements of {sup 234}U and {sup 232}Th in seawater followed by Edwards et al., (1987) who made combined {sup 234}U-{sup 230}Th measurements, was the full potential of mass spectrometric methods first realised. Several examples are given to illustrate various aspects of TIMS U-series 9 refs., 3 figs.

Detailed high-energy characteristics of AXP 4U 0142+61: Multi-year observations with INTEGRAL, RXTE, XMM-Newton, and ASCA

NARCIS (Netherlands)

den Hartog, P.R.; Kuiper, L.; Hermsen, W.; Kaspi, V.M.; Dib, R.; Knödlseder, J.; Gavriil, F.P.

2008-01-01

4U 0142+61 is one of the Anomalous X-ray Pulsars exhibiting hard X-ray emission above 10 keV discovered with INTEGRAL. In this paper we present detailed spectral and temporal characteristics both in the hard X-ray (> 10 keV) and soft X-ray (<10 keV) domains obtained using data from INTEGRAL,

In-depth analysis of cis-determinants that either promote or inhibit reinitiation on GCN4 mRNA after translation of its four short uORFs

Czech Academy of Sciences Publication Activity Database

Gunišová, Stanislava; Beznosková, Petra; Mohammad, Mahabub Pasha; Vlčková, Vladislava; Valášek, Leoš Shivaya

2016-01-01

Roč. 22, č. 4 (2016), s. 542-558 ISSN 1355-8382 R&D Projects: GA ČR(CZ) GAP305/11/0172 Institutional support: RVO:61388971 Keywords : translational control * reinitiation * uORF Subject RIV: CE - Biochemistry Impact factor: 4.605, year: 2016

The synthesis of [U-14C phenyl] LS 840606, an agricultural fungicide

International Nuclear Information System (INIS)

Madegard, G.; Mestre, P.; Raimond, P.; Noel, J.-P.

1995-01-01

2,2',4'-Trichloro-[ring U- 14 C]acetophenone was the key intermediate of this synthesis patterned after the industrial route. An unexpected poor yield was observed during the preparation by the Friedel-Crafts reaction of chloroacetyl chloride with 1,3-dichloro-[U- 14 C]benzene, possibly the result of an isotope effect although this poor yield might be explained by other factors. Two routes were checked for the preparation of 1,3-dichloro-[U- 14 C]benzene. The action of CCl 4 with 1,3-dinitro-[U- 14 C]benzene at 280 o C was entailed with explosions. A safer route started from [U- 14 C]aniline via 2,4-dichloro-[ring U- 14 C]acetanilide. Friedel-Crafts reaction with acetyl chloride gave rise in 52% yield to 2',4'-dichloro-[ring U- 14 C]acetophenone which was brominated to 2-bromo-2',4'-dichloro-[ring U- 14 C]acetophenone; was condensed with 2,2-ethylenedioxy)etylmagnesium bromide to compound, was condensed with 1,2,4-triazole then successively treated with HCl:water:dioxane and 2,2,2-trifluoroethanol/HCl. Separation of the two diastereomers by medium pressure liquid chromatography. 7% overall radioactivity yield from [U- 14 C]aniline. Radiochemical purity 99%. (author)

The urokinase receptor and its structural homologue C4.4A in human cancer

DEFF Research Database (Denmark)

Jacobsen, B; Ploug, M

2008-01-01

The urokinase-type plasminogen activator receptor (uPAR) and its structural homologue C4.4A are multidomain members of the Ly6/uPAR/alpha-neurotoxin protein domain family. Both are glycosylphosphatidylinositol-anchored membrane glycoproteins encoded by neighbouring genes located on chromosome 19q13...... that high protein expression in tumour cells of non-small cell pulmonary adenocarcinomas is associated with a particularly severe disease progression. This review will evaluate structural-functional and disease-related aspects of uPAR and C4.4A with a view to possible pharmacological targeting strategies...... in the human genome. The structural relationship between the two proteins is, however, not reflected at the functional level. Whereas uPAR has a well-established role in regulating and focalizing uPA-mediated plasminogen activation to the surface of those cells expressing the receptor, the biological function...

Primary and secondary structure of U8 small nuclear RNA

International Nuclear Information System (INIS)

Reddy, R.; Henning, D.; Busch, H.

1985-01-01

U8 small nuclear RNA is a new, capped, 140 nucleotides long RNA species found in Novikoff hepatoma cells. Its sequence is: m3GpppAmUmCGUCAGGA GGUUAAUCCU UACCUGUCCC UCCUUUCGGA GGGCAGAUAG AAAAUGAUGA UUGGAGCUUG CAUGAUCUGC UGAUUAUAGC AUUUCCGUGU AAUCAGGACC UGACAACAUC CUGAUUGCUU CUAUCUGAUUOH. This RNA is present in approximately 25,000 copies/cell, and it is enriched in nucleolar preparations. Like U1, U2, U4/U6, and U5 RNAs, U8 RNA was also present as a ribonucleoprotein associated with the Sm antigen. The rat U8 RNA was highly homologous (greater than 90%) to a recently characterized 5.4 S RNA from mouse cells infected with spleen focus-forming virus. In addition to the U8 RNA, three other U small nuclear RNAs were found in anti-Sm antibody immunoprecipitates from labeled rat and HeLa cells. Each of these contained a m3GpppAm cap structure; their apparent chain lengths were 60, 130, and 65 nucleotides. These U small nuclear RNAs are designated U7, U9, and U10 RNAs, respectively

Isotope shift of 234U, 236U, 238U in U I

International Nuclear Information System (INIS)

Gagne, J.M.; Nguyen Van, S.; Saint-Dizier, J.P.; Pianarosa, P.

1976-01-01

New and very accurate data of isotope shifts and relative isotope shifts in 234 U, 236 U, 238 U are presented. The invariance of the relative isotope shift, for the transitions we have investigated, supports the hypothesis that the so called specific mass effect is negligible in uranium

Correlation between oxidation and stress corrosion cracking of U-4.5 wt.% Nb

International Nuclear Information System (INIS)

Magnani, N.J.; Holloway, P.H.

1976-01-01

To investigate the mechanisms causing stress corrosion cracking on uranium alloys, the kinetics of crack propagation and oxide film growth for U-4.5 percent Nb were investigated at temperatures between 0 0 C and 200 0 C in oxygen, water vapor and oxygen-water vapor mixtures. Three regions of crack velocity rate versus stress intensity were observed in laboratory air. At low stress intensities (but above an effective K/sub ISCC/ of 22 MN/m/sup 3 / 2 /) crack velocity varied approximately as K 70 . In an intermediate stress intensity region (region II) the crack velocity was dependent upon K 4 . In the high stress intensity region, mechanical overloading was observed and crack velocities varied approximately as K 12 . Both cracking (region II) and oxidation rates were characterized by an activation energy of 7 kcal/mole. For stress corrosion cracking it was shown that oxygen was the primary stress corrodent, but a synergistic effect upon crack propagation rates was observed for oxygen-water vapor mixtures. Crack velocities were dependent upon the pressure of oxygen (P/sub O 2 //sup 1 / 3 /) and water vapor, while the oxidation rate was essentially independent of the pressure of these species. Stress sorption and oxide film formation stress corrosion cracking mechanisms were considered and reconciled with the stress corrosion and oxidation data

Experimental Investigation of Impact-Induced Molecular Desorption by 4.2 MeV/u Pb ions

CERN Document Server

Chanel, M; Laurent, Jean Michel; Madsen, N; Mahner, E

2001-01-01

In preparation for the heavy ion program of the LHC, accumulation and cooling test with lead ion beams have been performed in the LEAR storage ring. These tests have revealed that due to the unexpected, large outgassing of the vacuum system, the dynamic pressure of the ring could not be maintained low enough to reach the required beam intensities. To determine the actions necessary to lower the dynamic pressure rise, an experimental program has been initiated for measuring the molecular desorption yields of stainless steel vacuum chambers by the impact of 4.2 MeV/u lead ions with the charge states +27 and +53. The test chambers were exposed either at grazing or at perpendicular incidence. Different surface treatments are reported in terms of the molecular desorption yields for H2, CH4, CO and CO2. Unpexpected large values of molecular yields per incident ion up to 2x104 molecules/ion have been observed. The implications of these results for the vacuum system of the future ion accumulator ring (LEIR) and possi...

U(SMes*)n, (n = 3, 4) and Ln(SMes*)3 (Ln = La, Ce, Pr, Nd): lanthanide(III)/actinide(III) differentiation in agostic interactions and an unprecedented eta3 ligation mode of the arylthiolate ligand, from X-ray diffraction and DFT analysis.

Science.gov (United States)

Roger, Mathieu; Barros, Noémi; Arliguie, Thérèse; Thuéry, Pierre; Maron, Laurent; Ephritikhine, Michel

2006-07-12

Reaction of U(NEt(2))(4) with HS-2,4,6-(t)Bu(3)C(6)H(2) (HSMes) gave U(SMes)(3)(NEt(2))(py) (1), whereas similar treatment of U[N(SiMe(3))SiMe(2)CH(2)][N(SiMe(3))(2)](2) afforded U(SMes)[N(SiMe(3))(2)](3) (2) and U(SMes)(3)[N(SiMe(3))(2)]. The first neutral homoleptic uranium(IV) thiolate to have been crystallographically characterized, U(SMes)(4) (4), was isolated from the reaction of U(BH(4))(4) and KSMes. The first homoleptic thiolate complex of uranium(III), U(SMes)(3) (5), was synthesized by protonolysis of U[N(SiMe(3))(2)](3) with HSMes in cyclohexane. The crystal structure of 5 exhibits the novel eta(3) ligation mode for the arylthiolate ligand. Comparison of the crystal structure of 5 with those of the isomorphous lanthanide congeners Ln(SMes)(3) (Ln = La, Ce, Pr, and Nd) indicates that the U-S, U-C(ipso)(), and U-C(ortho)() bond lengths are shorter than the corresponding ones in the 4f-element analogues, when taking into account the variation in the ionic radii of the metals. The distance between the uranium and the carbon atoms involved in the U...H-C epsilon agostic interaction of each thiolate ligand is shorter, by approximately 0.05 A, than that expected from a purely ionic bonding model. The lanthanide(III)/actinide(III) differentiation was analyzed by density functional theory (DFT). The nature of the M-S bond is shown to be ionic strongly polarized at the sulfur for M = U and iono-covalent (i.e. strongly ionic with low orbital interaction), for M = Ln. The strength of the U...H-C epsilon agostic interaction is proposed to be controlled by the maximization of the interaction between U(+) and S(-) under steric constraints. The eta(3) ligation mode of the arylthiolate ligand is also obtained from DFT.

The disc-jet coupling in the neutron star X-ray binary 4U 1728-34

Science.gov (United States)

Tudose, Valeriu; Tzioumis, Anastasios; Belloni, Tomaso; Altamirano, Diego; Linares, Manuel; Mendez, Mariano; Hiemstra, Beike

2010-10-01

The present radio proposal is part of a multi-wavelength campaign focused on the study of the accretion/ejection process in the neutron star X-ray binary system 4U 1728-34. Our intention is to study the behaviour of the inner part of the accretion disc as inferred from the X-ray observations of the Fe emission line and the kHz quasi-periodic oscillations, and to link it to the properties of the radio jet. To achieve this goal we request 5 × 11h of observing time with ATCA, scheduled at regular intervals in the period 2010 August 27- October 13, the visibility window of the granted X-ray observations with RXTE (PI: Mendez) and Suzaku (PI: Linares).

Preparation of D-[U-14C]galactose and α-D-[U-14C]galactose-1-phosphate

International Nuclear Information System (INIS)

Kolina, J.; Hromadkova, B.

1989-01-01

Optically pure D-[U- 14 C]galactose was prepared on a preparatory scale using the galactokinase enzyme. The suggested procedure allows to also prepare a α-D-[U- 14 C]galactose-1-phosphate and L-[U- 14 ]galactose giving good yield. The experiments proved that the raw fraction isolated from yeast of the Kluyveromyces fragilis strain or the Kluyveromyces lactis strain shows sufficient activity. Phosphorylation of D-[U- 14 C]galactose practically terminates after 30 mins of incubation. DL-[U- 14 C]galactose isolated using preparatory paper chromatography from the acid hydrolyzate of [U- 14 C] polysaccharide is a satisfactory radioactive precursor. The developed preparation procedure theoretically contributed towards the further elucidation of the problem of the proportional representation of galactose stereo-isomers in extracellular polysaccharide isolated from red algae. In this respect data in the literature differ and some sources state a significantly higher propertion of L-galactose. The experiments showed that [U- 14 C] polysaccharide isolated from the red algae Porphyridium cruentum prevalently contains D-[U- 14 C]galactose, which confirms the process of enzyme reaction. (author). 1 tab., 4 refs

Kinetics and mechanism of photoaccelerated isotope exchange between U(VI) and U(IV) in oxalate solutions

International Nuclear Information System (INIS)

Shaban, I.S.; Owreit, M.F.; Nikitenko, S.I.

1992-01-01

A kinetic study of thermal and photoaccelerated U(IV)-U(VI) isotope exchange has been carried out in oxalate solutions at 11-40 deg C. The rate and quantum yield were determined as a function of U(IV), U(VI) and oxalate concentration, wavelength of incident light, temperature and absorbed dose of γ-radiation. The kinetic equations for thermal and photoaccelerated exchange have been obtained. It was assumed that the mechanism of exchange involves formation of U(V) as an intermediate, followed by slow exchange between U(V) and U(IV). The isokinetic dependence confirms the identity of limiting stages for thermal and photostimulated exchange. The upper component of photoexcited T 1 level of uranyl is supposed to be the most reactive in the process of U(V) generation. It was observed that the small doses of γ-radiation evoke the acceleration of isotope exchange, however, at D>100 krad the rate of exchange is reduced to the level of thermal exchange. (author) 8 refs.; 4 figs.; 2 tabs

State diagram of U-Al-Si as a basis for analysis of the processes in nuclear fuel compositions based on U(Al, Si)3 and U3Si compounds

International Nuclear Information System (INIS)

Chebotarev, N.T.; Konovalov, L.N.; Zhmak, V.A.; Chebotarev, Ya.N.

1996-01-01

Results of studies into the Al-UAl 3 -USi 3 -Si of the U-Al-Si ternary system are presented. It is established that phase equilibrium between the intermetallic compound U(Al, Si) 3 and the aluminium-silicon alloys may be presented in form of conodes on the isothermal cross-section of the state diagram. It is shown that the U(Al, Si) 3 intermetallic compound, containing up to 6.5 at.% silicon, interacts both with liquid and solid aluminium with the U(Al, Si) 4 phase formation [ru

Effect of anthropogenic organic complexants on the solubility of Ni, Th, U(IV) and U(VI)

Energy Technology Data Exchange (ETDEWEB)

Felipe-Sotelo, M., E-mail: m.felipe-sotelo@lboro.ac.uk [Department of Chemistry, Loughborough University, LE11 3TU Loughborough, Leicestershire (United Kingdom); Edgar, M. [Department of Chemistry, Loughborough University, LE11 3TU Loughborough, Leicestershire (United Kingdom); Beattie, T. [MCM Consulting. Täfernstrasse 11, CH 5405 Baden-Dättwil (Switzerland); Warwick, P. [Enviras Ltd., LE11 3TU Loughborough, Leicestershire (United Kingdom); Evans, N.D.M.; Read, D. [Department of Chemistry, Loughborough University, LE11 3TU Loughborough, Leicestershire (United Kingdom)

2015-12-30

Highlights: • Citrate increases the solubility of Ni, Th and U between 3 and 4 orders of magnitude. • Theophrastite is the solubility controlling phase of Ni in 95%-saturated Ca(OH){sub 2}. • U(VI) and Ni may form Metal-citrate-OH complexes stabilised by the presence of Ca{sup 2+}. - Abstract: The influence of anthropogenic organic complexants (citrate, EDTA and DTPA from 0.005 to 0.1 M) on the solubility of nickel(II), thorium(IV) and uranium (U(IV) and U(VI)) has been studied. Experiments were carried out in 95%-saturated Ca(OH){sub 2} solutions, representing the high pH conditions anticipated in the near field of a cementitious intermediate level radioactive waste repository. Results showed that Ni(II) solubility increased by 2–4 orders of magnitude in the presence of EDTA and DTPA and from 3 to 4 orders of magnitude in the case of citrate. Citrate had the greatest effect on the solubility of Th(IV) and U(IV)/(VI). XRD and SEM analyses indicate that the precipitates are largely amorphous; only in the case of Ni(II), is there some evidence of incipient crystallinity, in the form of Ni(OH){sub 2} (theophrastite). A study of the effect of calcium suggests that U(VI) and Ni(II) may form metal-citrate-OH complexes stabilised by Ca{sup 2+}. Thermodynamic modelling underestimates the concentrations in solution in the presence of the ligands for all the elements considered here. Further investigation of the behaviour of organic ligands under hyperalkaline conditions is important because of the use of the thermodynamic constants in preparing the safety case for the geological disposal of radioactive wastes.

Determination of 234U and 238U activity concentrations in groundwaters from three deep wells drilled in Itu Intrusive Suite (SP)

International Nuclear Information System (INIS)

Souza, Francisca de

2006-01-01

Activity concentrations of ( 234 U) and ( 238 U) were determined in groundwaters drawn from three deep wells drilled in rocks from Itu Intrusive Suite (SP), two located in Salto town (S and SY wells) and the other one in Itu (I well). Sampling was done from September, 2004 to December, 2005, and twelve samples of each well were collected monthly. For those determinations alpha spectrometry technique was used, providing high precision results, as shown by the very good agreement of the data obtained in the analyses of 23 duplicates. The waters from the three wells presented a considerable enrichment of 234 U in relation to 238 U, indicating an important radioactive disequilibrium of these isotopes. In well I, the activity concentrations of ( 238 U) varied from (1,06 +- 0,03) to (2,1+- 0,2) mBq/L and those of ( 234 U) spanned from (3,1 +- 0,2) to (6,0 +- 0,4) mBq/L, whereas ( 234 U/ 238 U) activity ratios did not present significant variation, during the sampling time interval, presenting an average of 2,8 +- 0,1. The S waters showed the lowest uranium concentrations and the largest diversity of ( 238 U) and ( 234 U) activity concentrations, which varied from (0,26 +- 0,02) to (1,07+- 0,08) mBq/L and from (1,8 +- 0,1) to (7,0 +- 0,5) mBq/L, respectively, and also presented variable ( 234 U/ 238 U) activity ratios, spanning from (2,79 +- 0,07) to (8,1+- 0,3). In SY well, ( 238 U) activities varied between (0,8 +- 0,1) and (4,2 +- 0,3) mBq/L and those ones of ( 234 U) from (14 +- 1) to (53 +- 4) mBq/L, whereas ( 234 U/ 238 U) ratios fell in the interval from 12,6 +- 0,3 to 18,3 +- 0,4, with the highest activities of both radioisotopes registered during the dry season and the lowest ones in the rainy time period. The ( 234 U/ 238 U) activity ratios, which were invariable during sampling period of well I, indicated the contribution of rainfall to recharge the aquifer. The observed correlation between those ratios and uranium concentrations, for S and SY wells, showed

Selective abrogation of the uPA-uPAR interaction in vivo reveals a novel role in suppression of fibrin-associated inflammation

DEFF Research Database (Denmark)

Connolly, Brian M; Choi, Eun Young; Gårdsvoll, Henrik

2010-01-01

the interaction between endogenous uPA and uPAR is selectively abrogated, whereas other functions of both the protease and its receptor are retained. Specifically, we introduced 4 amino acid substitutions into the growth factor domain (GFD) of uPA that abrogate uPAR binding while preserving the overall structure...... a principal in vivo role of the uPA-uPAR interaction in cell-associated fibrinolysis critical for suppression of fibrin accumulation and fibrin-associated inflammation and provides a valuable model for further exploration of this multifunctional receptor....

PODAAC-AQR40-4U7CS

Data.gov (United States)

National Aeronautics and Space Administration — The IPRC/SOEST Aquarius OI-SSS v4 product is a level 4, near-global, 0.5 degree spatial resolution, 7-day, optimally interpolated salinity dataset based on version...

A NuSTAR observation of the reflection spectrum of the low-mass X-ray binary 4U 1728-34

DEFF Research Database (Denmark)

Sleator, Clio C.; Tomsick, John A.; King, Ashley L.

2016-01-01

We report on a simultaneous NuSTAR and Swift observation of the neutron star low-mass X-ray binary 4U 1728-34. We identified and removed four Type I X-ray bursts during the observation in order to study the persistent emission. The continuum spectrum is hard and described well by a blackbody with...

Prehistoric spatial patterning and subsistence studies: Archaeological investigations at Sample Unit U19arP4, Nevada Test Site, Nye County, Nevada

International Nuclear Information System (INIS)

Johnson, W.G.; DuBarton, A.; Edwards, S.; Drollinger, H.

1992-01-01

This report documents the methods and results of archaeological investigations at Sample Unit U19arP4 on Pahute Mesa at the Nevada Test Site (NTS). Eight sites were located there: four lithic artifact scatters (26NY1370, 26NY1372, 26NY3666 and 26NY3667), two temporary camps (26NY3665 and 26NY5418), one artifact locality (26NY5419), and one quarry (26NY3664). One of the lithic scatters, 26NY3667, incorporated a previously recorded rock ring, 26NY1371, that could not be relocated during subsequent investigations. Surface artifacts were collected from all but two of the sites, 26NY1370 and 26NY1372. The data retrieved from these investigations include over one thousand artifacts, such as projectile points, bifaces, debitage, groundstone, and pottery. The temporally diagnostic materials indicate periodic use of Sample Unit U19arP4 from the Middle Archaic to the Shoshonean period

Critical experiments with 4.31 wt % 235U-enriched UO2 rods in highly borated water lattices

International Nuclear Information System (INIS)

Durst, B.M.; Bierman, S.R.; Clayton, E.D.

1982-08-01

A series of critical experiments were performed with 4.31 wt % 235 U enriched UO 2 fuel rods immersed in water containing various concentrations of boron ranging up to 2.55 g/l. The boron was added in the form of boric acid (H 3 BO 3 ). Critical experimental data were obtained for two different lattice pitches wherein the water-to-uranium oxide volume ratios were 1.59 and 1.09. The experiments provide benchmarks on heavily borated systems for use in validating calculational techniques employed in analyzing fuel shipping casks and spent fuel storage systems that may utilize boron for criticality control

The synthesis of [U-{sup 14}C phenyl] LS 840606, an agricultural fungicide

Energy Technology Data Exchange (ETDEWEB)

Madegard, G.; Mestre, P.; Raimond, P.; Noel, J.-P. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France)

1995-12-01

2,2`,4`-Trichloro-[ring U-{sup 14}C]acetophenone was the key intermediate of this synthesis patterned after the industrial route. An unexpected poor yield was observed during the preparation by the Friedel-Crafts reaction of chloroacetyl chloride with 1,3-dichloro-[U-{sup 14}C]benzene, possibly the result of an isotope effect although this poor yield might be explained by other factors. Two routes were checked for the preparation of 1,3-dichloro-[U-{sup 14} C]benzene. The action of CCl{sub 4} with 1,3-dinitro-[U-{sup 14} C]benzene at 280{sup o}C was entailed with explosions. A safer route started from [U-{sup 14}C]aniline via 2,4-dichloro-[ring U-{sup 14}C]acetanilide. Friedel-Crafts reaction with acetyl chloride gave rise in 52% yield to 2`,4`-dichloro-[ring U-{sup 14}C]acetophenone which was brominated to 2-bromo-2`,4`-dichloro-[ring U-{sup 14}C]acetophenone; was condensed with 2,2-(ethylenedioxy)etylmagnesium bromide to compound, was condensed with 1,2,4-triazole then successively treated with HCl:water:dioxane and 2,2,2-trifluoroethanol/HCl. Separation of the two diastereomers by medium pressure liquid chromatography. 7% overall radioactivity yield from [U-{sup 14}C]aniline. Radiochemical purity 99%. (author).

The behavior of the slope of elastic nucleon scattering at small transfer momenta and recent U A 4/2 data

International Nuclear Information System (INIS)

Goloskokov, S.V.; Kuleshov, S.P.; Selyugin, O.V.

1993-01-01

Theoretical predictions for the behavior of the slope of the nucleon-nucleon scattering and other parameters of the differential cross sections in the framework of the dynamic model are compared with the recent U A 4/2 data at small transfer momenta and at a centre-of-mass energy of 541 GeV. Predictions at superhigh energies are considered. (author.). 13 refs.; 1 fig.; 1 tab

Analysis list: E2f4 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available E2f4 Blood,Embryonic fibroblast,Liver,Muscle,Pluripotent stem cell + mm9 http://dba...rchive.biosciencedbc.jp/kyushu-u/mm9/target/E2f4.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/E2f4....5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/E2f4.10.tsv http://dbarchive.biosciencedbc....jp/kyushu-u/mm9/colo/E2f4.Blood.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/E2f4....Embryonic_fibroblast.tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/E2f4.Liver.tsv,htt

Laboratory studies of 235U enrichment by chemical separation methods

International Nuclear Information System (INIS)

Daloisi, P.J.; Orlett, M.J.; Tracy, J.W.; Saraceno, A.J.

1976-01-01

Laboratory experiments on 235 U enrichment processes based on column redox ion exchange, electrodialysis, and gas exchange chromatography performed from August 1972 to September 1974 are summarized. Effluent from a 50 to 50 weight mixture of U +4 and U +6 (as UO 2 2+ ), at a total uranium concentration of 5 mg U per ml in 0.25N H 2 SO 4 -0.03N NaF solution, passing through a 100 cm length cation exchange column at 0.5 ml/min flow rates, was enriched in 235 U by 1.00090 +- .00012. The enriched fraction was mostly in the +6 valence form while the depleted fraction was U +4 retained on the resin. At flow rates of 2 ml/min, the enrichment factor decreases to 1.00033 +- .00003. In the electrodialysis experiments, the fraction of uranium diffusing through the membranes (mostly as +6 valence state) in 4.2 hours is enriched in 235 U by 1.00096 +- .00012. Gas exchange chromatography tests involved dynamic and static exposure of UF 6 over NaF. In dynamic tests, no significant change in isotopic abundance occurred in the initial one-half weight cut of UF 6 . The measured relative 235 U/ 238 U mole ratios were 1.00004 +- .00004 for these runs. In static runs, enrichment became evident. For the NaF(UF 6 )/sub x/-UF 6 system, there is 235 U depletion in the gas phase, with a single-stage factor of 1.00033 at 100 0 C and 1.00025 at 25 0 C after 10 days of equilibration. The single-stage or unit holdup time is impractically long for all three chemical processes

Equilibrium relationships in the system Ni-U-O

International Nuclear Information System (INIS)

Mansour, N.A.L.

1980-01-01

Phase relationships were established in air and in oxygen. Mixtures of NiO and U 3 O 8 oxidize to NiUO 4 . The results of analysis of NiUO 4 were identical to those previously published for NiU 3 O 10 . The uranate dissociates to NiO and U 3 O 8 at a temperature higher than that of their oxidation back to the uranate on cooling because of the difficulty of oxygen diffusion and uranate nucleation. Accordingly, dissociation temperature was taken to represent equilibrium and was used to calculate roughly ΔH and ΔS for the reaction of dissociation. In presence of NiO, U 3 O 8 melts partially and does not dissociate to the lower oxide. (orig.) [de

Extraction of Th and U from Swiss granites

International Nuclear Information System (INIS)

Bajo, C.

1980-12-01

The extraction, at the laboratory level, of U and Th from Swiss granites is discussed. The Mittagfluh, Bergell and Rotondo granites and the Giuv syenite offered a wide range of U and Th concentrations; 7.7 to 20.0 ppm U and 25.5 to 67.0 ppm Th. U and Th were determined in the leach solutions by the fission track method and by spectrophotometry, respectively. Samples containing less than 0.3 μg U and 4 μg Th, could be measured with an accuracy of 10% for U and 5% for Th. Leach tests were performed during which the following parameters were varied: granite-type, grain size, acid-type, acid concentration, temperature and time. There were very great leaching differences between the granites studied. Temperature was the most important parameter. Sharp differences in extraction occurred between 20 0 C, 50 0 C and 80 0 C. At 80 0 C, more than 85% U and Th were extracted. The extraction curve (percent extracted as a function of time) of aliquots sampled after 1, 2, 4, 8, 12 and 24 hours showed a plateau after 8 hours. The half life of the reaction was between one and two hours. As a general rule, Th was better extracted than U. (Auth.)

Characterization of the interaction layer in diffusion couples U-Mo-Zr/Al and U-Mo-Zr/Al-A356 at 550 C degrees

International Nuclear Information System (INIS)

Komar Varela, Carolina; Arico, Sergio; Mirandou, Marcela; Balart, Silvia; Gribaudo, Luis

2007-01-01

Out-of-pile diffusion experiments were performed between U-7 wt.% Mo-1 wt.% Zr and Al or Al A356 (7,1 wt.% Si) at 550 C degrees. In this work morphological characterization and phase identification on both interaction layers are presented. They were carried out by the use of different techniques: optical and scanning electron microscopy, X-ray diffraction and WDS microanalysis. In the interaction layer U-7 wt.% Mo-1 wt.% Zr/Al, the phases UAl 3 , UAl 4 , Al 20 Mo 2 U and Al 43 Mo 4 U 6 were identified. Similar results in the interaction layer of the U-7 % Mo/Al at 580 C degrees were previously obtained. In the interaction layer U-7 wt.% Mo-1 wt.% Zr/Al A356, the phases U(Al,Si) 3 with 25 at.% Si and Si 5 U 3 were identified. This last phase, with a higher Si concentration, was identified with X-ray diffraction synchrotron radiation performed at the National Synchrotron Light Laboratory, Campinas, Brazil. (author) [es

The Determination of the Half-Life of U{sup 238} by Absolute Counting of {alpha} Particles in a 4 {pi}-Liquid Scintillation Counter; Determination de la periode de l'U{sup 238} au moyen du comptage absolu de particules {alpha} dans un comtpeur 4 {pi} a scintillateur liquide; Opredelenie perioda poluraspadda U{sup 238} posredstvom absolyutnogo scheta {alpha}-chastits v zhidkostnom stsintillyatsionnom schetchike 4 {pi}; Determinacion del periodo del U{sup 238} por recuento absoluto de las particulas {alpha} con un contador 4 {pi} de centelleador liquido

Energy Technology Data Exchange (ETDEWEB)

Steyn, J; Strelow, F W. E. [Council of Scientific and Industrial Research, Pretoria (South Africa)

1960-06-15

The specific activity of natural uranium was determined by liquid scintillation {alpha}-counting. Uranium was extracted from its decay products by methyl isobutyl ketone extraction and samples of this solution were added directly to the liquid scintillator. A quantitative investigation was made of the separation of uranium from thorium by the extraction method employed. Assuming that U{sup 238} and U{sup 234} were in equilibrium, and correcting for the presence of U{sup 235}, the specific activity and the half-life of the isotope U{sup 238} were calculated. (author) [French] L'activite specifique de l'uranium naturel est determinee au moyen d'un comptage a par scintillateur liquide. L'uranium est separe de ses produits de desintegration par une extraction a la methylisobutylceton e et des echantillons de cette solution sont ajoutes directement au scintillateur liquide. On fait une etude quantitative de la separation de l'uranium et du thorium par le procede d'extraction utilise. En admettant que U{sup 238} et U{sup 234} sont en equilibre et en faisant la correction voulue pour tenir compte de la presence de U{sup 235}, on calcule l'activite specifique et la periode de U{sup 238}. (author) [Spanish] La actividad especifica del uranio natural se determino con un contador {alpha} de centelleador liquido. El uranio se separo de productes de desintegracion por extraccion con metilisobutilcetona, y muestras de esta solucion se anadieron directamente al centelleador liquido. Se estudio cuantitativament e el grado de separacion uranio/torio alcanzado con el metodo de extraccion empleado. Introduciendo correcciones para tener en cuenta la presencia de U{sup 235}, se calculo la actividad especifica y el periodo de semidesintegracio n del U{sup 238} suponiendo que este isotopo se encontraba en equilibrio con el U{sup 234}. (author) [Russian] Spetsificheskaya aktivnost' estestvennogo urana byla opredelena s pomoshch'yu zhidkostnogo stsintillyatsionnog o schetchika {alpha

Abandoned Well Program. Version 2.0. Volume 4

Science.gov (United States)

1988-09-01

5175.69 26098 2183059 186116 5230.06 26137 2179058 190172 5185.52 27001 2173573 190790 5128.00 27008 2173329 189912 5129.30 27014 2178077 190522 5171.80...e ~ N Lfl r-41 -N C4 to I ISO ’o 9-4) z .0 c I I c c U304 W " F " 40 U4U o1 C1 C14 0- IN i 0 U) "*4 .4 -04 -1, -0 so w c S.a c0 a~b 4J 4 3 1 c 1. 1

Dicty_cDB: Contig-U10291-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U10291-1 no gap 932 4 3203354 3204286 PLUS 2 2 U10291 0 0 1 0 0 0 1 0 0 0 0 0 0 0 Show Contig...-U10291-1 Contig ID Contig-U10291-1 Contig update 2002. 9.13 Contig sequence >Contig-U10291-1 (Contig...-U10291-1Q) /CSM_Contig/Contig-U10291-1Q.Seq.d GTAAAGGTTTTATGTGTATATTTTTTAATGACCTTTTCGAATTAGTTTCA ...CAAAATAGATTAAATCTTAGTTACTCTCATGC TAATCAATATGTTGAGAGTTTTCCATCACAAATGTTATCAACAATTGCAA AATTCATTAGTTTCTTATTTGGTT...SLMYSL FNYIFDENGIIKSEFQDPTQRKRLSRGLSRRFMTIGILGLFTTPFIFFFLLINFFFEYAE ELKNRPGSLFSREWSPLARWEFRELNELPHYFQNRLNLSY

The moduli space of two U(1) instantons on noncommutative $R^4$ and $R^3\\times S^1$

OpenAIRE

Lee, Kimyeong; Tong, David; Yi, Sangheon

2000-01-01

We employ the ADHM method to derive the moduli space of two instantons in U(1) gauge theory on a noncommutative space. We show by an explicit hyperK\\"ahler quotient construction that the relative metric of the moduli space of two instantons on $R^4$ is the Eguchi-Hanson metric and find a unique threshold bound state. For two instantons on $R^3\\times S^1$, otherwise known as calorons, we give the asymptotic metric and conjecture a completion. We further discuss the relationship of caloron modu...

On a phase transition of a Kosterlitz-thouless-type in the d=4, U(1)-lattice gauge theory

International Nuclear Information System (INIS)

Marchetti, D.H.U.; Perez, J.F.

1986-12-01

The d=4, U(1)-lattice gauge theory with the Villain action may be represented as a locally neutral gas of topological (plaquette) charges which interact via a logarithmically confining potential, is shown. Using this representation a renormalization group analysis to show the existence of a phase transition of the Kosterlitz-Thouless-type was performed. An improved hierarchical version of the model which displays (unlike the usual Migdal-Kadanoff approach) a stable line of gaussian fixed points at low temperatures, which should correspond to the usual deconfining region of these systems is presented. (Author) [pt

U(SMes*)n, (n=3, 4) and Ln(SMes*)3 (Ln = La, Ce, Pr, Nd): Lanthanide(III)/actinide(III) differentiation in agostic interactions and an unprecedented eta(3) Ligation mode of the aryl-thiolate ligand, from X-ray diffraction and DFT analysis

International Nuclear Information System (INIS)

Roger, Mathieu; Barros, Noemi; Arliguie, Therese; Thuery, Pierre; Maron, Laurent; Ephritikhine, Michel

2006-01-01

Reaction of U(NEt 2 ) 4 with HS-2,4,6- t Bu 3 C 6 H 2 (HSMes*) gave U(SMes*) 3 (NEt 2 )(py) (1), whereas similar treatment of U[N(SiMe 3 )SiMe 2 CH 2 ][N(SiMe 3 ) 2 ] 2 afforded U(SMes*)[N(SiMe 3 ) 2 ] 3 (2) and U(SMes*) 3 [N(SiMe 3 ) 2 ]. The first neutral homoleptic uranium(IV) thiolate to have been crystallographically characterized, U(SMes*) 4 (4), was isolated from the reaction of U(BH 4 ) 4 and KSMes*. The first homoleptic thiolate complex of uranium(III), U(SMes*) 3 (5), was synthesized by proton-lysis of U[N(SiMe 3 ) 2 ] 3 with HSMes* in cyclohexane. The crystal structure of 5 exhibits the novel η 3 ligation mode for the aryl-thiolate ligand. Comparison of the crystal structure of 5 with those of the isomorphous lanthanide congeners Ln(SMes*) 3 (Ln) La, Ce, Pr, and Nd) indicates that the U-S, U-C ipso , and U-C ortho bond lengths are shorter than the corresponding ones in the 4f-element analogues, when taking into account the variation in the ionic radii of the metals. The distance between the uranium and the carbon atoms involved in the U center dot center dot center dot H-C ε agostic interaction of each thiolate ligand is shorter, by ∼ 0.05 angstrom, than that expected from a purely ionic bonding model. The lanthanide( III)/actinide(III) differentiation was analyzed by density functional theory (DFT). The nature of the M-S bond is shown to be ionic strongly polarized at the sulfur for M) U and ion-covalent (i.e. strongly ionic with low orbital interaction), for M) Ln. The strength of the U center dot center dot center dot H-C ε agostic interaction is proposed to be controlled by the maximization of the interaction between U + and S - under steric constraints. The η 3 ligation mode of the aryl-thiolate ligand is also obtained from DFT. (authors)

Heavy-ion induced desorption yields of cryogenic surfaces bombarded with 4.2 MeV/u lead ions

CERN Document Server

Mahner, E; Evans, L; Kollmus, H; Küchler, D; Scrivens, R; Severin, D; Wengenroth, M; CERN. Geneva. ATS Department

2011-01-01

The ion-induced desorption experiment, installed in the CERN Heavy-Ion Accelerator LINAC 3, has been used to study the dynamic outgassing of cryogenic surfaces. Two different targets, bare and goldcoated copper, were bombarded under perpendicular impact with 4.2 MeV/u Pb54+ ions. Partial pressure rises of H2, CH4, CO, and CO2 and effective desorption yields were measured at 300, 77, and 6.3 K using single shot and continuous ion bombardment techniques. We find that the heavy-ion-induced desorption yield is temperature dependent and investigate the influence of CO gas cryosorbed at 6.3 K. The gain in desorption yield reduction at cryogenic temperature vanishes after several monolayers of CO are cryosorbed on both targets. In this paper we describe the new cryogenic target assembly, the temperature-dependent pressure rise, desorption yield, and gas adsorption measurements.

Multinuclear NMR spectroscopy of the tetrahedral uranium(IV) complex U(BH3CH3)4

International Nuclear Information System (INIS)

Gamp, E.; Shinomoto, R.; Edelstein, N.; McGarvey, B.R.

1987-01-01

The temperature dependence of the 1 H, 11 B, and 13 C NMR spectra of T/sub d/ U(BH 3 CH 3 ) 4 in solution is reported. The paramagnetic shifts are interpreted as originating purely from spin delocalization mechanisms with no contribution from the metal-orbital dipolar interaction. It is shown that the temperature dependence of both 1 H shifts (bridging and terminal protons) is identical with that calculated from a polarization theory which assumes the shift is proportional to the average value of electron spin in the inner 5f orbitals. The proportionality constant is -5.64 MHz for the bridging protons and -0.59 MHz for the terminal protons. The temperature dependences of 11 B and 13 shifts are found to depart significantly from that predicted by the polarization theory with the largest deviations shown by the 11 B shifts. It is shown how those deviations can be accounted for by postulating a second spin delocalization through direct covalency involving molecular orbitals formed from the uranium 5f orbitals and ligand s and p orbitals. 29 references, 4 figures, 3 tables

Comparison of U-Pu-Mo, U-Pu-Nb, U-Pu-Ti and U-Pu-Zr alloys

International Nuclear Information System (INIS)

Boucher, R.; Barthelemy, P.

1964-01-01

The data concerning the U-Pu, U-Pu-Mo and U-Pu-Nb are recalled. The results obtained with U-Pu-Ti and U-Pu-Zr alloys containing 15-20 per cent Pu and 10 wt. per cent ternary element are reported. The transformation temperatures, the expansion coefficients, the nature of phases, the thermal cycling behaviour have been determined. A list of the principal properties of these different alloys is presented and the possibilities of their use as fast reactor's fuel element are considered. The U-Pu-Ti alloys seem to be quite promising: easiness of fabrication, large thermal stability, excellent behaviour in air, small quantity of zeta phase, temperature of solidus superior to 1100 deg. C. (authors) [fr

Dicty_cDB: Contig-U13974-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U13974-1 no gap 1782 1 1265322 1267105 PLUS 29 32 U13974 0 0 0 1 2 0 22 0 4 0 0 0 0 0 Show Contig...-U13974-1 Contig ID Contig-U13974-1 Contig update 2002.12.18 Contig sequence >Contig-U13974-1 (Contig...-U13974-1Q) /CSM_Contig/Contig-U13974-1Q.Seq.d AAGAGTTAAAACAAAAATAAAAAAATAAAATAAAAAAAAAAAATTAA...TAAAACAAATAA ACATTAAAATGATATTTAGGTTTTAAATTTAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA Gap no gap Contig...TTRKIYVYDNQNFFPIDNQGFD VDPAKRIYLNEKKTYHNYHFCMKMNTVFTYKGYEVFNFRGDDDVWVFINNKLVIDLGGLH SPIGTSVDTMTLGLTIG

Dicty_cDB: Contig-U11342-1 [Dicty_cDB

Lifescience Database Archive (English)

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Introduction: U.S. Homophile Internationalism.

Science.gov (United States)

Stein, Marc

2017-01-01

This article introduces "U.S. Homophile Internationalism," a special issue of the Journal of Homosexuality. The introduction provides a broad overview of the "U.S. Homophile Internationalism" archive and exhibit, which was published on the Outhistory Web site in 2015. The archive and exhibit consists of more than 800 U.S. homophile magazine articles, letters, and other items that referenced non-U.S. regions of the world from 1953 to 1964. The essays in the special issue focus on (1) Africa; (2) Asia and the Pacific; (3) Canada; (4) Latin America and the Caribbean; (5) the Middle East; and (6) Russia, the Soviet Union, and Eastern Europe. There is also an article that addresses the public history and digital humanities dimensions of the project. The introduction concludes by discussing the essays' common goals, themes, and concerns.

A System for Individualizing Instruction. Practical Answers to U-SAIL Implementation Questions. Monograph No. 4.

Science.gov (United States)

Utah System Approach to Individualized Learning Project.

The U-SAIL system is a practical approach to individualization of instruction in which a problem-solving process is employed to install a program in logical sequential phases. U-SAIL is a nationally validated, successfully replicated, cost-feasible system for individualization of instruction which can be implemented in a variety of settings with…

Studies of 4He emission in both fusion-like and inelastic reactions of 340-MeV 40Ar + 238U

International Nuclear Information System (INIS)

Kildir, M.; Logan, D.; Kaplan, M.; Zisman, M.S.; Guerreau, D.; Alexander, J.M.; Vaz, L.C.

1982-01-01

The fission-fragment angular correlation technique has been used in conjunction with a position-sensitive avalanche detector to identify the fusion-like and inelastic collisions of 340-MeV 40 Ar + 238 U. For each of these two reaction types, we have characterized the correlated 4 He emission by measuring three-fold coincidences between two fission fragments and the light charged particle. We find an abundance of both evaporation-like and direct 4 He emission, each of which is associated with both fusion-fission and sequential-fission processes. Several comparison tests of both the coincidence and singles data strongly indicate that very little 4 He emission is due to evaporation from accelerated fission fragments in this system. The evaporative 4 He emission appears instead to have a strong contribution originating from the composite system prior to fission. The forward angle 4 He emissions, characterized by prominent forward-peaking and relatively high energies, suggest an origin associated with the very early stages of the collision

Dicty_cDB: Contig-U04334-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U04334-1 no gap 399 4 3746420 3746021 MINUS 3 3 U04334 0 0 0 0 0 0 3 0 0 0 0 0 0 0 Show Contig...-U04334-1 Contig ID Contig-U04334-1 Contig update 2001. 8.29 Contig sequence >Contig-U04334-1 (Contig...-U04334-1Q) /CSM_Contig/Contig-U04334-1Q.Seq.d CAAAAAAAAAAAAGTAAAACAATAAATTATATAAAAAAAATAAAAAAAAT...CTAATTTCA AACAATATCAATAAAATGTTATATAATTACTATTAAAATGAAAAAAAAA Gap no gap Contig len...ce QKKKSKTINYIKKIKKMSIINTISKLSLSNSLKSNITIGNLNGTTVNNYTHNETSSKFTE FFYKII*qnkrwf*kvkelnkkkrkkdyiissfcklysiyfvfs

Dicty_cDB: Contig-U15306-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U15306-1 no gap 2452 3 3887051 3889342 PLUS 54 91 U15306 0 0 0 49 4 1 0 0 0 0 0 0 0 0 Show Contig...-U15306-1 Contig ID Contig-U15306-1 Contig update 2004. 6.11 Contig sequence >Contig-U15306-1 (Contig...-U15306-1Q) /CSM_Contig/Contig-U15306-1Q.Seq.d AAGCATAAACGGTGAATACCTCGACTCCTAAATCGATGAAGACCGTA...TTTTAGAACTTCAAAAAATAGTAC AAATTTTTTCAAATTAAGATAAAAAAAATAAAACAAAAATTAATTTAAAA CA Gap no gap Contig length 2452...*naagtgkgeegrt*hkslpywlapqvkgsvmprggqghygasrggrkhmgidfssivg qdivapisgkvvnfkgartkypmlqlypskkftefdylqmlyvhppvginmgasyqvsvg dtig

Dicty_cDB: Contig-U13202-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U13202-1 no gap 1083 4 1301578 1302630 PLUS 41 45 U13202 8 0 13 0 0 2 16 0 2 0 0 0 0 0 Show Contig...-U13202-1 Contig ID Contig-U13202-1 Contig update 2002.12.18 Contig sequence >Contig-U13202-1 (Contig...-U13202-1Q) /CSM_Contig/Contig-U13202-1Q.Seq.d ACTGTTGGCCTACTGGGATTTTCTGCAGTAATAATAAAATCAAATA...TTTGTAATTTTAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA Gap no gap Contig len...kvgqfirvprgaqpaqtskftlmih*gvkshffsmlqpnwpncttigpvq nqarcgsllgfwvlqnqlltvlcihnnekcsikfygygyl**nlitvvkvvmpslhg

Development of an U and Pu recovery process by molten salt electrorefining. Behavior of U and Pu at simultaneous recoveries into liquid cadmium cathodes

International Nuclear Information System (INIS)

Uozumi, Koichi; Kato, Tetsuya; Iizuka, Masatoshi; Inoue, Tadashi; Iwai, Takashi; Shirai, Osamu; Arai, Yasuo

2003-01-01

In order to study behaviors of U and Pu at simultaneous recoveries into liquid cadmium cathodes (LCCs) in the electrorefining of pyrometallurgical reprocessing, several experiments were conducted to recover U and Pu into LCCs at different U/Pu ratios in the salt phase. The major results were as follows: (1) The weight ratios of U and Pu in 120 g LCCs reached 10 wt.% (the tentative target), with current efficiencies higher than 80 %. (2) Under the conditions of U/Pu ratios in the initial salt phase less than 1/4.3, the amounts of recovered U and Pu were proportional to the passed electric charges, with the separation factors of U to Pu (= (U/Pu ration in the recovered product)/(U/Pu ratio in the salt)) between 1.2 and 2.0. (3) On the other hand, under the condition of U/Pu ratio in the initial salt phase at 1/1.73, only U was recovered into the LCC after the saturation of LCC with U and Pu. Accordingly, there will be a threshold in the U/Pu ratio of the salt phase for the simultaneous recovery of U and Pu. (4) Am showed a similar behavior to Pu. The separation factors of Am to Pu (=(AM/Pu ratio in the recovered product)/(Am/Pu ratio in the salt)) was 0.78, which means that Am is co-recovered with Pu into LCC. (author)

Molecular desorption of stainless steel vacuum chambers irradiated with 4.2 MeV/u lead ions

CERN Document Server

Mahner, E; Laurent, Jean Michel; Madsen, N

2003-01-01

In preparation for the heavy ion program of the Large Hadron Collider (LHC) at CERN, accumulation and cooling tests with lead ion beams have been performed in the Low Energy Antiproton Ring (LEAR). These tests have revealed that due to the unexpected large outgassing of the vacuum system, the dynamic pressure of the ring could not be maintained low enough to reach the required beam intensities. To determine the actions necessary to lower the dynamic pressure rise, an experimental program has been initiated for measuring the molecular desorption yields of stainless steel vacuum chambers by the impact of 4.2 MeV/u lead ions with the charge states +27 and +53. The test chambers were exposed either at grazing or at perpendicular incidence. Different surface treatments (glow-discharges, non-evaporable getter coating) are reported in terms of the molecular desorption yields for H2, CH4, CO, Ar and CO2. Unexpected large values of molecular yields per incident ion up to 2 104 molecules/ion have been observed. The red...

Timing Studies and QPO Detection for Transient Xray Pulsar 4u 0115+634 by RXTE.

Science.gov (United States)

Ram Dugair, Moti; Jaaffrey, S. N. A.

We present results of timing analysis of data of the transient X-ray pulsar 4U 0115+634 (Neu-tron star with fast spin entry) taken by the Rossi X-ray Timing Explorer (RXTE) space satellite. We first time observed the occurrence of 3 QPOs of 3 m Hz, 8 m Hz and 60 m Hz of the X-ray outburst of 2008. In particular the frequencies of the QPO's may be attributed to those of oscillations of disturbance occuring in the inner region of the accreted disk of the neutron star during the truncation of viscous circum stellar disc around the Be-star. The role of the interaction between the neutron star and the circumstellar is very important. Appearance of three QPOs in X-ray Binary system is a new phenomenon and difficult to understand.

Coupling of Yang-Mills to N=4, d=4 supergravity

International Nuclear Information System (INIS)

Bergshoeff, E.; Koh, I.G.; Sezgin, E.

1985-01-01

We couple N=4, d=4 supersymmetric Yang-Mills theory to supergravity. The scalars of the theory parametrize the coset (SO(n,6)/[SO(n)xSO(6)])xSU(1,1)/U(1)). Keeping the composite local SO(n)xSO(6)xU(1) invariance intact, we gauge an (n+6) parameter subgroup of SO(n,6) which is either (i) SU(2)xSU(2)xH(dim H=n), (ii) SO(4,1)xH(dim H=n-4) or (iii) SO(6,1)xH(dim H=n-15). In all these cases the theory has an indefinite potential. (orig.)

Coupling of Yang-Mills to N=4, d=4 supergravity

International Nuclear Information System (INIS)

Bergshoeff, E.; Koh, I.G.; Sezgin, E.

1985-01-01

We couple N=4, d=4 supersymmetric Yang-Mills theory to supergravity. The scalars of the theory parametrize the coset ((SO(n,6)/SO(n)xSO(6))x((SU(1,1)/U(1)). Keeping the composite local SO(n)xSO(6)xU(1) invariance intact, we gauge an (n+6) parameter subgroup of SO(n,6) which is either (i) SU(2)xSU(2)xH (dim H=n), (ii) SO(4,1)xH (dim H=n-4) or (iii) SO(6,1)xH (dim H=n-15). In all these cases the theory has an indefinite potential. (author)

Swift/BAT and RXTE Observations of the Peculiar X-ray Binary 4U 2206+54 - Disappearance of the 9.6 Day Modulation

Science.gov (United States)

Corbet, R. H. D.; Markwardt, C.; Tueller, J.

2007-01-01

Observations of the high-mass X-ray binary 4U 2206+54 with the Swift Burst Alert Telescope (BAT) do not show modulation at the previously reported period of 9.6 days found from observations made with the Rossi X-ray Timing Explorer (RXTE) All-Sky Monitor (ASM). Instead, the strongest peak in the power spectrum of the BAT light curve occurs at a period of 19.25+/-0.08 days, twice the period found with the RXTE ASM. The maximum of the folded BAT light curve is also delayed compared to the maximum of the folded ASM light curve. The most recent ASM data folded on twice the 9.6 day period show 'similar morphology to the folded BAT light curve. This suggests that the apparent period doubling is a recent secular change rather than an energy-dependent effect. The 9.6 day period is thus not a permanent strong feature of the light curve. We suggest that the orbital period of 4U 2206+54 may be twice the previously proposed value.

Tetragonal phase in Al-rich region of U-Fe-Al system

International Nuclear Information System (INIS)

Meshi, L.; Zenou, V.; Ezersky, V.; Munitz, A.; Talianker, M.

2005-01-01

A new ternary aluminide U 2 FeAl 20 with the approximate composition Al-4.2at% Fe-8.5at% U was observed in the Al-rich corner of the U-Al-Fe system. Transmission electron microscopy and electron microdiffraction technique were used for characterization of the structure of this phase. It has a tetragonal unit cell with the parameters a=12.4A and c=10.3A and can be described by the space group I4-bar 2m

Advancing Understanding of the +4 Metal Extractant Thenoyltrifluoroacetonate (TTA-); Synthesis and Structure of MIVTTA4 (MIV = Zr, Hf, Ce, Th, U, Np, Pu) and MIII(TTA)4- (MIII = Ce, Nd, Sm, Yb).

Science.gov (United States)

Cary, Samantha K; Livshits, Maksim; Cross, Justin N; Ferrier, Maryline G; Mocko, Veronika; Stein, Benjamin W; Kozimor, Stosh A; Scott, Brian L; Rack, Jeffrey J

2018-04-02

Thenoyltrifluoroacetone (HTTA)-based extractions represent popular methods for separating microscopic amounts of transuranic actinides (i.e., Np and Pu) from macroscopic actinide matrixes (e.g. bulk uranium). It is well-established that this procedure enables +4 actinides to be selectively removed from +3, + 5, and +6 f-elements. However, even highly skilled and well-trained researchers find this process complicated and (at times) unpredictable. It is difficult to improve the HTTA extraction-or find alternatives-because little is understood about why this separation works. Even the identities of the extracted species are unknown. In addressing this knowledge gap, we report here advances in fundamental understanding of the HTTA-based extraction. This effort included comparatively evaluating HTTA complexation with +4 and +3 metals (M IV = Zr, Hf, Ce, Th, U, Np, and Pu vs M III = Ce, Nd, Sm, and Yb). We observed +4 metals formed neutral complexes of the general formula M IV (TTA) 4 . Meanwhile, +3 metals formed anionic M III (TTA) 4 - species. Characterization of these M(TTA) 4 x- ( x = 0, 1) compounds by UV-vis-NIR, IR, 1 H and 19 F NMR, single-crystal X-ray diffraction, and X-ray absorption spectroscopy (both near-edge and extended fine structure) was critical for determining that Np IV (TTA) 4 and Pu IV (TTA) 4 were the primary species extracted by HTTA. Furthermore, this information lays the foundation to begin developing and understanding of why the HTTA extraction works so well. The data suggest that the solubility differences between M IV (TTA) 4 and M III (TTA) 4 - are likely a major contributor to the selectivity of HTTA extractions for +4 cations over +3 metals. Moreover, these results will enable future studies focused on explaining HTTA extractions preference for +4 cations, which increases from Np IV to Pu IV , Hf IV , and Zr IV .

Dicty_cDB: Contig-U09640-1 [Dicty_cDB

Lifescience Database Archive (English)

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Dicty_cDB: Contig-U14745-1 [Dicty_cDB

Lifescience Database Archive (English)

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Dicty_cDB: Contig-U16086-1 [Dicty_cDB

Lifescience Database Archive (English)

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Dicty_cDB: Contig-U15541-1 [Dicty_cDB

Lifescience Database Archive (English)

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A year-by-year record of 236-U/238-U in coral as a step towards establishing 236-U from nuclear weapons testing fall-out as oceanic tracer

Energy Technology Data Exchange (ETDEWEB)

Winkler, Stephan; Steier, Peter [University of Vienna, Faculty of Physics, Vienna (Austria); Carilli, Jessica [Australian Nuclear Science and Technology Organisation, Lucas Heights (Australia)

2012-07-01

Since uranium is known to behave conservatively in ocean waters, 236-U has great potential in application as oceanic tracer. 236-U (t1/2=23.4 Ma) was introduced into the oceans by atmospheric nuclear weapon testing with amount estimates ranging from 700 kg to 1500 kg. Thus a resulting initial average 236-U/238-U ratio of at least 5e-9 is expected for an oceanic mixed layer depth of 100 m. This ratio is already higher than the natural pre-nuclear background, which is expected to be at 10e-14 levels. Even the elevated ratios of global stratospheric fall-out are beyond the capabilities of ICPMS and TIMS methods. However, the exceptional sensitivity and ultra-low background for 236-U of the Vienna Environmental Research Accelerator's Accelerator Mass Spectrometry system allows us to measure down to 10-13 detection limits. We present a year-by-year record of 236-U/238-U for a Caribbean coral core covering years 1944 to 2006, thus allowing to us put constraints on the oceanic input of 236-U by atmospheric testing. Moreover modeling of the results also demonstrates the capabilities of 236-U as oceanic tracer.

Dicty_cDB: Contig-U15005-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U15005-1 no gap 2023 1 1509217 1507616 MINUS 2 4 U15005 0 0 0 0 1 0 1 0 0 0 0 0 0 0 Show Contig...-U15005-1 Contig ID Contig-U15005-1 Contig update 2004. 6.11 Contig sequence >Contig-U15005-1 (Contig...-U15005-1Q) /CSM_Contig/Contig-U15005-1Q.Seq.d AATTTTCTTTTCTTTTTAAAACTTAAGTACCATATGGCAGAATATACAC...ATAATAACGATATTAA Gap no gap Contig length 2023 Chromosome number (1..6, M) 1 Chro...HMAEYTHYFIQYNLTDIFYEDVNIEKYSCSICYESVYKKEIYQCKEIHWF CKTCWAESLFKKKECMICRCIVKSISELSRNRFIEQDFLNIKVNCPNSFKYIDENKNNNN KIKDLENGCKDIITIG

Dicty_cDB: Contig-U10406-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U10406-1 no gap 661 4 1621526 1620875 MINUS 1 1 U10406 0 0 1 0 0 0 0 0 0 0 0 0 0 0 Show Contig...-U10406-1 Contig ID Contig-U10406-1 Contig update 2002. 9.13 Contig sequence >Contig-U10406-1 (Contig...-U10406-1Q) /CSM_Contig/Contig-U10406-1Q.Seq.d NNNNNNNNNNATAAGTAAAAGAGTTATTGGTCCAAGATTAGATGATGACA...TACAAATAAGTAAAGTTG ATAAAGAACAT Gap no gap Contig length 661 Chromosome number (1....cid sequence XXXISKRVIGPRLDDDNNNNDNDKFNNNNKKAIGPSRIGPTIGPSIGPSRYNTNNNDSNH NSNNDDDDDSSEEDEEDTKSEWERVRNMIENNKN

Dicty_cDB: Contig-U01997-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U01997-1 gap included 886 2 1683026 1682230 MINUS 3 4 U01997 1 0 0 0 0 0 2 0 0 0 0 0 0 0 Show Contig...-U01997-1 Contig ID Contig-U01997-1 Contig update 2001. 8.29 Contig sequence >Contig-U01997-1 (Contig-U01997-1Q) /CSM_Contig/Contig-U01997...ATTGAAATAATATTTATTTATTTTTTTAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA Gap gap included Contig...nfkvfgieiifiyffkkkkkkkkkkkkkkkkkkk own update 2004. 6. 9 Homology vs CSM-cDNA Query= Contig-U01997-1 (Contig-U01997-1Q) /CSM_Contig.../Contig-U01997-1Q.Seq.d (896 letters) Database: CSM 6905 sequences; 5,674,871 total l

Dicty_cDB: Contig-U10823-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U10823-1 gap included 1750 1 3559501 3561234 PLUS 85 124 U10823 0 5 0 30 1 0... 0 20 0 29 0 0 0 0 Show Contig-U10823-1 Contig ID Contig-U10823-1 Contig update 2002.12.18 Contig sequence >Contig-U10823-1 (Contig...-U10823-1Q) /CSM_Contig/Contig-U10823-1Q.Seq.d ACTGTTGGCCTACTGGTATTTTTGGTAGTGTGTTAAAA...CAACAAATAAAATTAAAATTA GTTATATTTTTTTTAAATTAAAAAAAAAAATAAAAAAAATAAATTATTTA TTAAATTTTT Gap gap included Contig ...4. 6.10 Homology vs CSM-cDNA Query= Contig-U10823-1 (Contig-U10823-1Q) /CSM_Contig/Contig-U10823-1Q.Seq.d (1

US EPA's SPECIATE 4.4 Database: Development and Uses

Science.gov (United States)

SPECIATE is the U.S. Environmental Protection Agency’s (EPA) repository of volatile organic gas and particulate matter (PM) speciation profiles of air pollution sources. EPA released SPECIATE 4.4 in early 2014 and, in total, the SPECIATE 4.4 database includes 5,728 PM, volatile o...

EPA’s SPECIATE 4.4 Database:Development and Uses

Science.gov (United States)

SPECIATE is the U.S. Environmental Protection Agency's (EPA)repository of volatile organic gas and particulate matter (PM) speciation profiles for air pollution sources. EPA released SPECIATE 4.4 in early 2014 and, in total, the SPECIATE 4.4 database includes 5,728 PM, VOC, total...

A theory of piezoelectric, elastic, and dielectric properties of the KH2PO4 family crystals under the strain u6. Phase transition and the piezoelectric effect in the KH2PO4 crystal

International Nuclear Information System (INIS)

Levits'kij, R.R.; Lyisnij, B.M.

2003-01-01

In order to study the dielectric, piezoelectric and elastic properties of ferroelectrics and antiferroelectrics of the KH 2 PO 4 family, we consider an extended proton tunneling model that takes into account the shear strain u 6 . In the four-particle cluster approximation for the short-range interactions and the mean field approximation for the long-range interaction we calculate the transverse components of the dielectric susceptibility tensor of the KH 2 PO 4 family ferroelectrics

Dynamics of nucleus nucleus collisions below 100 MeV/u a study with a 4π detection array

International Nuclear Information System (INIS)

Peter, J.

1990-06-01

Charged particles and fragments emitted in reactions between 40 Ar, at energies ranging from 25 to 85 MeV/u, and an 27 Al target have been detected in a geometry close to 4π in the center of mass with the multidetector array MUR + TONNEAU. A new global variable, the average parallel velocity, has been used to sort the events as a function of the impact parameter value. The multiplicity of pre-equilibrium charged particles emitted from the interaction region (participants) increases strongly when the impact parameter value decreases, and reaches 7 in head-on reactions. The flow of these particles is attributed to scattering at negative angles. When the energy increases, compression gradually opposes this negative scattering, until the flow falls to zero. This is obtained at a beam energy in the range 70-80 MeV/u for impact parameters below 2 fm and increases with the impact parameter. This study as a function of the impact parameter and the energy should allow information both on the nucleon-nucleon cross section in medium and the equation of state of nuclear matter to be obtained

Wind accretion in the massive X-ray binary 4U 2206+54: abnormally slow wind and a moderately eccentric orbit

Science.gov (United States)

Ribó, M.; Negueruela, I.; Blay, P.; Torrejón, J. M.; Reig, P.

2006-04-01

Massive X-ray binaries are usually classified by the properties of the donor star in classical, supergiant and Be X-ray binaries, the main difference being the mass transfer mechanism between the two components. The massive X-ray binary 4U 2206+54 does not fit in any of these groups, and deserves a detailed study to understand how the transfer of matter and the accretion on to the compact object take place. To this end we study an IUE spectrum of the donor and obtain a wind terminal velocity (v_∞) of ~350 km s-1, which is abnormally slow for its spectral type. We also analyse here more than 9 years of available RXTE/ASM data. We study the long-term X-ray variability of the source and find it to be similar to that observed in the wind-fed supergiant system Vela X-1, reinforcing the idea that 4U 2206+54 is also a wind-fed system. We find a quasi-period decreasing from ~270 to ~130 d, noticed in previous works but never studied in detail. We discuss possible scenarios for its origin and conclude that long-term quasi-periodic variations in the mass-loss rate of the primary are probably driving such variability in the measured X-ray flux. We obtain an improved orbital period of P_orb=9.5591±0.0007 d with maximum X-ray flux at MJD 51856.6±0.1. Our study of the orbital X-ray variability in the context of wind accretion suggests a moderate eccentricity around 0.15 for this binary system. Moreover, the low value of v_∞ solves the long-standing problem of the relatively high X-ray luminosity for the unevolved nature of the donor, BD +53°2790, which is probably an O9.5 V star. We note that changes in v_∞ and/or the mass-loss rate of the primary alone cannot explain the different patterns displayed by the orbital X-ray variability. We finally emphasize that 4U 2206+54, together with LS 5039, could be part of a new population of wind-fed HMXBs with main sequence donors, the natural progenitors of supergiant X-ray binaries.

238U content in soils of Byelorussia

International Nuclear Information System (INIS)

Shagalova, Eh.D.

1986-01-01

Results of detection in Byelorussian soils of a heavy natural radionuclide 238 U and its content in humus horizons of the soils on map-schemes are presented. 238 U content is determined by complete decomposition of soils by acids, isolation from thorium using EhDEh-10 P anionite and subsequent solution colorimetry. It is shown that the content of uranium-238 in soils decreases from the North to the South. Its maximum amount (>2x10 -4 %) is detected in turfy-podsolic soils in lake-glacier loams; the minimum one ( -4 %)- in peatymarshy soils. The map-scheme of 238 U content is a background base. Using the background base it is possible to trace the change in uranium content in soils under conditions of technogenic effect and to substantiate the efficiency of environment protection measures

Superconductivity in the U(Th)-Y-Ba-Cu-O systems

International Nuclear Information System (INIS)

Qin Qizong; He Adi; Jia Weijie; Ma Lidun; Cheng Huansheng; Hua Zhongyi

1989-01-01

High T c superconductivity has been observed both resistively and magnetically in the new U(Th)-Y-Ba-Cu-O systems. The zero resistance temperature of the three samples with nominal composition of U 0.1 Y 1.1 Ba 0.8 Cu O 4-z , U 0.15 Y 1.05 Ba 0.8 Cu 4-z and Th 0.3 Y 0.8 Ba 0.8 Cu 4-z is 87K, 79K and 74K, respectively. The result of ac magnetic susceptibility measurement implies that the superconducting state is realized in the U-doped samples below 90K. The stoichimetry of the U-Y-Ba-Cu O superconductors has the aid of Rutherford backscattering and nuclear reaction 16 O(d, p) 17 O. The analytical results show that the 'real composition' of somples may be different from that of the nomial composition. The X ray diffraction analysis of the U-Y-Ba-Cu-O system shows that none of the peaks can be fitted to the uranium oxides and the other raw materiale structure, and its pattern may be attributed to new multiple phases with structure different from the known singlephase superconducting oxides

Dicty_cDB: Contig-U15828-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U15828-1 gap included 1593 1 4184040 4182448 MINUS 12 19 U15828 0 0 6 0 0 0 ...0 0 2 0 4 0 0 0 Show Contig-U15828-1 Contig ID Contig-U15828-1 Contig update 2004. 6.11 Contig sequence >Contig-U15828-1 (Contig...-U15828-1Q) /CSM_Contig/Contig-U15828-1Q.Seq.d ATAAAAAAAATTAAAAAATTAAAAAAGTTATCCACCCAAGT...ACA AATATTATAACTGGTACTGCTACTGTTTCAATCCCTCAAAAAAATTTAAT TTATATTTTACCAAATTCAAATACAATTAATCAATCAACAATTACAATTA CAA Gap gap included Contig...SFNPANSDFSFSYNINTTITQPTQIYLNQDIYYPNGFTTNIITGTATVSIPQ KNLIYILPNSNTINQSTITIT own update 2004. 6.23 Homology vs CSM-cDNA Query= Contig

Dicty_cDB: Contig-U15525-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U15525-1 gap included 3361 6 202399 204109 PLUS 34 57 U15525 0 0 7 0 7 6 0 0 4 3 7 0 0 0 Show Contig...-U15525-1 Contig ID Contig-U15525-1 Contig update 2004. 6.11 Contig sequence >Contig-U15525-1 (Contig-U15525-1Q) /CSM_Contig/Contig-U15525...ATTTAATTAAATAATAATA Gap gap included Contig length 3361 Chromosome number (1..6, M) 6 Chromosome length 3595...TEATCLILSVD ETVQNNQAEQAQAGPQINNQTRQALSRVEVFKQ--- ---LDTIGIKKESGGGLGDSQFIAGAAFKRTFFYAGFEQQPKHIKNPKVLCLNIELELK...lslnsiqslpqlkqlv*ssll mkpfkiiklnklklvhklitkhvklyhg*rcss--- ---LDTIGIKKESGGGLGDSQFIAGAAFKRTFFYAGFEQQPKHIKNPKV

Dicty_cDB: Contig-U15573-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U15573-1 gap included 2005 4 5020093 5018210 MINUS 13 13 U15573 0 5 0 1 1 0 ...0 0 0 1 1 0 2 2 Show Contig-U15573-1 Contig ID Contig-U15573-1 Contig update 2004. 6.11 Contig sequence >Contig-U15573-1 (Contig...-U15573-1Q) /CSM_Contig/Contig-U15573-1Q.Seq.d AGTCTTGAGCTTTTATTGGGTCAACCATTGGGTGAATATAC... AGCNTTAACNGGNAA Gap gap included Contig length 2005 Chromosome number (1..6, M) ...xxlfrsnxslxxxxxxsxnxx Frame C: s*afigstig*iyiylkrfhlfl*skryyqskw*fkifpilkqttiiyen

Solubility Determination of Uranium (IV) Oxalates U(C2O4)2.6H2O and M2U2(C2O4)5.nH2O (M = mono-charged cation)

International Nuclear Information System (INIS)

Costenoble, Sylvain; Grandjean, Stephane; Arab-Chapelet, Benedicte; Abraham, Francis

2008-01-01

The solubility of uranium (IV) oxalate compounds was studied in order to have a precise insight of the behaviour of An(IV)-An(III) (An(IV) = U, Np or Pu and An(III) = Pu or Am) mixed oxalate in the context of oxalic co-conversion for actinide co-management. Concepts of thermodynamics of aqueous-solid solution are reviewed by introducing LIPPMANN theory and THORSTENSON and PLUMMER 'stoichiometric saturation' model in a way to understand and model the system of interest. Different analytical techniques have been developed in order to titrate uranium and/or other actinides at trace levels in solution. This thorough investigation is the basis of further experiments on the solubility of mixed U(IV)- An(III) oxalate solid solutions as a function of the nature of the trivalent actinide and the An(III)/U(IV) ratio. (authors)

Comparative investigation of the solution species [U(CO3)5]6- and the crystal structure of Na6[U(CO3)5].12H2O.

Science.gov (United States)

Hennig, Christoph; Ikeda-Ohno, Atsushi; Emmerling, Fanziska; Kraus, Werner; Bernhard, Gert

2010-04-21

The limiting U(IV) carbonate species in aqueous solution was investigated by comparing its structure parameters with those of the complex preserved in a crystal structure. The solution species prevails in aqueous solution of 0.05 M U(IV) and 1 M NaHCO(3) at pH 8.3. Single crystals of Na(6)[U(CO(3))(5)].12H(2)O were obtained directly from this mother solution. The U(IV) carbonate complex in the crystal structure was identified as a monomeric [U(CO(3))(5)](6-) anionic complex. The interatomic distances around the U(IV) coordination polyhedron show average distances of U-O = 2.461(8) A, U-C = 2.912(4) A and U-O(dist) = 4.164(6) A. U L(3)-edge EXAFS spectra were collected from the solid Na(6)[U(CO(3))(5)].12H(2)O and the corresponding solution. The first shell of the Fourier transforms (FTs) revealed, in both samples, a coordination of ten oxygen atoms at an average U-O distance of 2.45 +/- 0.02 A, the second shell originates from five carbon atoms with a U-C distance of 2.91 +/- 0.02 A, and the third shell was fit with single and multiple scattering paths of the distal oxygen at 4.17 +/- 0.02 A. These data indicate the identity of the [U(CO(3))(5)](6-) complex in solid and solution state. The high negative charge of the [U(CO(3))(5)](6-) anion is compensated by Na(+) cations. In solid state the Na(+) cations form a bridging network between the [U(CO(3))(5)](6-) units, while in liquid state the Na(+) cations seem to be located close to the anionic complex. The average metal-oxygen distances of the coordination polyhedron show a linear correlation to the radius contraction of the neighbouring actinide(IV) ions and indicate the equivalence of the [An(CO(3))(5)](6-) coordination within the series of thorium, uranium, neptunium and plutonium.

U.S. Korean Youth's Ideas and Experience of U.S. Education, U.S. Society, and U.S. History

Science.gov (United States)

An, Sohyun

2009-01-01

Drawing on and conversing with the large body of research and literature on young people's historical understanding, Asian American education, transnational migration, and Korean American studies, this dissertation research explored contemporary U.S. Korean youth's ideas and experiences of U.S. education, U.S. society and U.S. history.…

Characteristics of chemical binding to alpha 2u-globulin in vitro--evaluating structure-activity relationships

International Nuclear Information System (INIS)

Borghoff, S.J.; Miller, A.B.; Bowen, J.P.; Swenberg, J.A.

1991-01-01

alpha 2u-Globulin (alpha 2u) has been shown to accumulate in the kidneys of male rats treated with 2,2,4-trimethylpentane (TMP). 2,4,4-Trimethyl-2-pentanol (TMP-2-OH), a metabolite of TMP, is found reversibly bound to alpha 2u isolated from the kidneys of these treated rats. The objectives of the following study were to characterize the ability of [3H]TMP-2-OH to bind to alpha 2u in vitro and to determine whether other compounds that cause this protein to accumulate have the same binding characteristics. Although compounds that have been shown to cause the accumulation of alpha 2u in male rat kidneys compete in vitro with [3H]TMP-2-OH for binding to alpha 2u, they do so to varying degrees. The binding affinity (Kd) of the [3H]TMP-2-OH-alpha 2u complex was calculated to be on the order of 10(-7) M. The inhibition constant values (Ki) determined for d-limonene, 1,4-dichlorobenzene, and 2,5-dichlorophenol were all in the range 10(-4) M, whereas the Ki values for isophorone, 2,4,4- or 2,2,4-trimethyl-1-pentanol, and d-limonene oxide were determined to be in the range 10(-6) and 10(-7) M, respectively. TMP and 2,4,4- and 2,2,4-trimethylpentanoic acid did not compete for binding. This suggests that other factors, besides binding, are involved in the accumulation of alpha 2u. In this study the ability of a chemical to bind to alpha 2u was used as a measure of biological activity to assess structure-activity relationships among the chemicals tested and known to cause the accumulation of alpha 2u. The results so far suggest that binding is dependent on both hydrophobic interactions and hydrogen bonding

Synthesis of [3-14C]- and [phenyl-U-14C] olaquindox

International Nuclear Information System (INIS)

Maul, W.; Scherling, D.; Seng, F.

1981-01-01

Olaquindox is a new feed additive. [ 14 C]Olaquindox, labelled in different positions, was needed for tracer-studies of pharmacokinetics, biotransformation and residues in several species of animals. 2-[N-(2-hydroxethyl)-carbamoyl]-3-methyl-[3- 14 C]quinoxaline-1,4-dioxide([3- 14 C]Olaquindox) was synthesized from barium[ 14 C]carbonate (22 mmoles; 1.15 Ci) via [1- 14 C]acetic acid, sodium[1- 14 C]acetate, [1- 14 C]acetylchloride, ethyl[3- 14 C]acetoacetate and 2-carbethoxy-3-methyl-[3- 14 C]quinoxaline-1,4-dioxide with an overall yield of 10%, based on barium[ 14 C]carbonate. The radiochemical purity was better than 98% (tlc). The specific activities of three preparations were 10.5, 8.4 and 5.45 μCi/mg respectively. [phenyl-U- 14 C]Olaquindox was synthesized starting from [U- 14 C]aniline (19.8 mmoles; 284.4 mCi). Intermediate products were N-acetyl[U- 14 C]aniline, 2-nitro-N-acetyl[U- 14 C]aniline, 2-nitro[U- 14 C]aniline and [U- 14 C]benzofurazanoxide. The total yield was 50% as calculated for [U- 14 C]aniline. At calibration samples of two preparations showed specific activities of 49.5 and 11.1 μCi/mg respectively. The radiochemical purity was checked by tlc and exceeded 98%. (author)

Mianningite, (□,Pb,Ce,Na) (U"4"+,Mn,U"6"+) Fe"3"+_2(Ti,Fe"3"+)_1_8O_3_8, a new member of the crichtonite group from Maoniuping REE deposit, Mianning county, southwest Sichuan, China

International Nuclear Information System (INIS)

Ge, Xiangkun; Fan, Guang; Chen, Zhangru; Ai, Yujie; Li, Guowu

2017-01-01

Mianningite (IMA 2014-072), ideally (□,Pb,Ce,Na)(U"4"+,Mn,U"6"+) Fe"3"+_2(Ti,Fe"3"+)_1_8O_3_8, is a new member of the crichtonite group from the Maoniuping REE deposit, Mianning county, Sichuan province, China. It was found in fractures of lamprophyre veins and in the contact between lamprophyre and a later quartz-alkali feldspar syenite dyke with REE mineralization, and is named after its type locality. Associated minerals are microcline, albite, quartz, iron-rich phlogopite, augite, muscovite, calcite, baryte, fluorite, epidote, pyrite, magnetite, hematite, galena, hydroxylapatite, titanite, ilmenite, rutile, garnet-group minerals, zircon, allanite-(Ce), monazite-(Ce), bastnaesite-(Ce), parisite-(Ce), maoniupingite-(Ce), thorite, pyrochlore-group minerals and chlorite. Mianningite occurs as opaque subhedral to euhedral tabular crystals, up to 1-2 mm in size, black in color and streak, and with a submetallic luster. Mianningite is brittle, with a conchoidal fracture. Its average micro-indentation hardness is 83.8 kg/mm"2 (load 0.2 kg), which is equivalent to ∝6 on the Mohs hardness scale. Its measured and calculated densities are 4.62 (8) g/cm"3 and 4.77 g/cm"3, respectively. Under reflected light, mianningite is grayish white, with no internal reflections. It appears isotropic and exhibits neither bireflectance nor pleochroism. The empirical formula, calculated on the basis of 38 O atoms per formula unit (apfu), is [□_0_._3_2_2(Pb_0_._2_1_5Ba_0_._0_3_7Sr_0_._0_3_6Ca_0_._0_1_0)_Σ_0_._2_9_8(Ce_0_._1_2_8La_0_._0_7_7Nd_0_._0_1_2)_Σ_0_._2_1_7 (Na_0_._1_2_7K_0_._0_3_6)_Σ_0_._1_6_3]_Σ_0_1_._0_0_0(U"4"+_0_._4_4_7Mn_0_0_._2_9_3U"6 "+_0_._1_1_2Y_0_._0_9_1Zr_0_._0_2_3Th_0_._0_1_1)_Σ_0_._9_7_7(Fe"3"+_1_._2_2_4Fe"2"+_0_._2_4_3Mg_0_._0_2_3P_0_._0_0_8Si_0_._0_0_6 □_0_._4_9_6)_Σ_2_._0_0_0(Ti_1_2_._4_6_4Fe"3"+_5_._2_9_2V"5"+_0_._1_1_8Nb_0_._0_8_3Al_0_._0_2_6Cr"3"+_0_._0_1_7)_Σ_1_8_._0_0_0O_3_8. Mianningite is trigonal, belongs to the space group R anti 3, and has

Evidence for the presence of U-Mo-Al ternary compounds in the U-Mo/Al interaction layer grown by thermal annealing: a coupled micro X-ray diffraction and micro X-ray absorption spectroscopy study

International Nuclear Information System (INIS)

Palancher, H.; Martin, P.; Nassif, V.

2007-01-01

The systematic presence of the ternary phases U 6 Mo 4 Al 43 and UMo 2 Al 20 is reported in a U-Mo/Al interaction layer grown by thermal annealing. This work shows, therefore, the low Mo solubility in UAl 3 and UAl 4 binary phases; it contradicts the hypothesis of the formation of (U,Mo)Al 3 and (U,Mo)Al 4 solid solutions often admitted in the literature. Using μ-XAS (micro X-ray absorption spectroscopy) at the Mo K edge and μ-XRD (micro X-ray diffraction), the heterogeneity of the interaction layer obtained on a γ-U 0.85 Mo 0.15 /Al diffusion couple has been precisely investigated. The UMo 2 Al 20 phase has been identified at the closest location from the Al side. Moreover, μ-XRD mapping performed on an annealed fuel plate enabled the characterization of the four phases resulting from the γ-U 0.85 Mo 0.15 /Al and (U 2 Mo+α-U)/Al interactions. A strong correlation between the concentrations of UAl 4 and UMo 2 Al 20 and those of UAl 3 and U 6 Mo 4 Al 43 has been shown. (orig.)

The high energy X-ray spectrum of 4U 0900-40 observed from OSO 8

Science.gov (United States)

Dolan, J. F.; Crannell, C. J.; Dennis, B. R.; Frost, K. J.; Orwig, L. E.; Ellison, D. C.

1981-01-01

The X-ray source 4U 0900-40 (= Vela XR-1) was observed with the high-energy X-ray spectrometer on OSO 8 for one week in 1976 and three weeks in 1978. Spectra of the source are presented above 16 keV. No systematic difference exists between the X-ray eclipse centers and the eclipse centers predicted from optical ephermerides. Short period intrinsic variability in the system's X-ray intensity may be related to changes in the Compton scattering optical depth in the system and does not require sporadic mass transfer via Roche lobe overflow. The 282 s modulation in the source's X-ray flux above 21 keV consists of two essentially similar pulses per period, most easily interpreted as arising from the two different magnetic poles of a rotating neutron star. The secondary appears to be a spherically accreting, magnetic neutron star.

Dicty_cDB: Contig-U09615-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U09615-1 gap included 1134 3 4459395 4458259 MINUS 1 2 U09615 0 0 1 0 0 0 0 0 0 0 0 0 0 0 Show Contig...-U09615-1 Contig ID Contig-U09615-1 Contig update 2002. 9.13 Contig sequence >Contig-U09615-1 (Contig-U09615-1Q) /CSM_Contig/Contig-U0961...TGCAAGATTAGAAAGATTAGAAAAAGATGCTATGCTAAAAATA Gap gap included Contig length 1134 Chromosome number (1..6, M) ...*wcnlyfrcre*emgkcn iefhiintrfkiwphrcidtighnvgicw**fnfecsfisleiqyrv**mgirfkyw*ww s*c*irpyfnnhafqyydyiwwskfwh*...4. 6.10 Homology vs CSM-cDNA Query= Contig-U09615-1 (Contig-U09615-1Q) /CSM_Contig/Contig-U09615-1Q.Seq.d (1

U-series isotopes in arc magma

Energy Technology Data Exchange (ETDEWEB)

Hawkesworth, C.; Turner, S.; McDermott, F.; Peate, D.; Van Calsteren, P.

1997-12-31

Thorium is not readily mobilized in the fluid component along destructive plate margins. Uranium is mobilized, and the resultant fractionation in U/Th can be used to estimate the rates of transfer slab derived components through the mantle wedge. The variations in Th/Yb, and by implication in the fractionation-corrected Th abundances of arc magmas largely depend on the contributions from subducted sediments. It is inferred that the distinctive high Th/Ta ratios of subduction related magmas primarily reflect the Th/Ta ratios of the subducted sediments, and that such high Th/Ta ratios are generated by processes other than those associated with recent subduction-related magmatism. Uranium and thorium isotopes have also been used to evaluate magma residence times within the crust. Thus, separated minerals and groundmass from six rocks erupted in the last 4,000 years from Soufriere on St. Vincent in the Lesser Antilles, scatter about a 50,000 year errorchron on the U-Th equiline diagram (Heath et al., 1977). Models are currently being developed to investigate how such apparent ages may relate to calculated replenishment times in steady state systems. Bulk continental crust has a lower U/Th ratio (0.25) than at least some estimates for the bulk Earth (0.26) and the depleted upper mantle (0.39). However, the island arc rocks with low U/Th ratios appear to have inherited those from subducted sediments, and arc rocks with a low sediment contribution have significantly higher U/Th. Consequently, the U/Th ratios of new crustal material generated along destructive plate margins are significantly higher than those of bulk continental crust. The low average U/Th of bulk crust may be primarily due to different crust generation processes in the Archaean, when U would be less mobile because conditions were less oxidising, and when residual garnet may have had more of a role in crust generation processes. Extended abstract. 4 figs., 23 refs.

Dicty_cDB: Contig-U09694-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U09694-1 gap included 1129 1 4027135 4026071 MINUS 3 4 U09694 2 0 1 0 0 0 0 0 0 0 0 0 0 0 Show Contig...-U09694-1 Contig ID Contig-U09694-1 Contig update 2002. 9.13 Contig sequence >Contig-U09694-1 (Contig-U09694-1Q) /CSM_Contig/Contig-U0969...TTAAATTAAAACAACAACAATTTCATAATATAAATAAT Gap gap included Contig length 1129 Chromosome number (1..6, M) 1 Chr...iklkqqqfklkqqqfhninn own update 2004. 6.10 Homology vs CSM-cDNA Query= Contig-U09694-1 (Contig-U09694-1Q) /CSM_Contig/Contig...E Sequences producing significant alignments: (bits) Value Contig-U09694-1 (Contig-U09694-1Q) /CSM_Contig

EPAs SPECIATE 4.4 Database: Development and Uses

Science.gov (United States)

SPECIATE is the U.S. Environmental Protection Agency’s (EPA) repository of source category-specific particulate matter (PM), volatile organic gas, and other gas speciation profiles of air pollutant emissions. Abt Associates, Inc. developed SPECIATE 4.4 through a collaborat...

In vivo kinetics of U4/U6.U5 tri-snRNP formation in Cajal bodies

Czech Academy of Sciences Publication Activity Database

Novotný, Ivan; Blažíková, Michaela; Staněk, David; Heřman, P.; Malínský, Jan

2011-01-01

Roč. 22, č. 4 (2011), s. 513-523 ISSN 1059-1524 R&D Projects: GA ČR GA204/07/0133; GA AV ČR KAN200520801 Institutional research plan: CEZ:AV0Z50520514; CEZ:AV0Z50390512; CEZ:AV0Z50390703 Keywords : small nuclear ribonucleoprotein * body components * dynamics Subject RIV: EB - Genetics ; Molecular Biology Impact factor : 4.942, year: 2011

Development of U-Mo Research Reactor Fuel for Next Generation

International Nuclear Information System (INIS)

Park, Jong Man; Lee, Y. S.; Yang, J. H.; Ryu, H. J.; Kim, C. K.; Chae, H. T.; Seo, C. G.

2010-08-01

- Exportation of centrifugal atomized U-Mo powder - Completion of post irradiation examination for KOMO-3 irradiated fuel rods. - Select the dispersion fuel rod candidates for KOMO-4 irradiation test. - Irradiation test to solve the problems of interaction layer formation (KOMO-4) - Set the post irradiation examination of KOMO-4 irradiated fuel rods. - Development and characterization of innovative high U density fuel rods - Obtain and analyze foreign new irradiation test D

Common TNF-α, IL-1β, PAI-1, uPA, CD14 and TLR4 polymorphisms are not associated with disease severity or outcome from Gram negative sepsis

Directory of Open Access Journals (Sweden)

Eugen-Olsen Jesper

2007-09-01

Full Text Available Abstract Background Several studies have investigated single nucleotide polymorphisms (SNPs in candidate genes associated with sepsis and septic shock with conflicting results. Only few studies have combined the analysis of multiple SNPs in the same population. Methods Clinical data and DNA from consecutive adult patients with culture proven Gram negative bacteremia admitted to a Danish hospital between 2000 and 2002. Analysis for commonly described SNPs of tumor necrosis-α, (TNF-α, interleukin-1β (IL-1β, plasminogen activator-1 (PAI-1, urokinase plasminogen activator (uPA, CD14 and toll-like receptor 4 (TLR4 was done. Results Of 319 adults, 74% had sepsis, 19% had severe sepsis and 7% were in septic shock. No correlation between severity or outcome of sepsis was observed for the analyzed SNPs of TNF-α, IL-1β, PAI-1, uPA, CD14 or TLR-4. In multivariate Cox proportional hazard regression analysis, increasing age, polymicrobial infection and haemoglobin levels were associated with in-hospital mortality. Conclusion We did not find any association between TNF-α, IL-1β, PAI-1, uPA, CD14 and TLR4 polymorphisms and outcome of Gram negative sepsis. Other host factors appear to be more important than the genotypes studied here in determining the severity and outcome of Gram negative sepsis.

Dicty_cDB: Contig-U12073-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U12073-1 gap included 912 2 2118980 2119867 PLUS 4 5 U12073 0 0 0 2 0 0 0 1 0 1 0 0 0 0 Show Contig...-U12073-1 Contig ID Contig-U12073-1 Contig update 2002.12.18 Contig sequence >Contig-U12073-1 (Contig...-U12073-1Q) /CSM_Contig/Contig-U12073-1Q.Seq.d CTGTTGGCCTACTGGNAATTGAAACAATTGTTTCAGCAAATATTA...AAGA Gap gap included Contig length 912 Chromosome number (1..6, M) 2 Chromosome length 8467578 Start point ...GPXSXDY*r own update 2004. 6.10 Homology vs CSM-cDNA Query= Contig-U12073-1 (Contig-U12073-1Q) /CSM_Contig/Contig

The effect of U.V.-irradiation on lambda DNA transcription

International Nuclear Information System (INIS)

Ranade, S.S.

1977-01-01

The effect of U.V.-irradiation of template DNA has been studied in vitro in the E.coli RNA polymerase system with native and U.V.-treated lambda DNA. Lambda DNA was more susceptible to U.V. than was calf-thymus DNA, yet a residual activity was observed at a U.V. dose of 0.5 x 10 4 erg/mm 2 . From the kinetic analysis of the reaction and the incorporation of lambda 32 P-labelled nucleoside triphosphates, it seems reasonable to conclude that U.V.-irradiation probably did not affect the DNA initiation sites, recognizable by RNA polymerase. The transcription products made with U.V.-irradiated lambda DNA were asymmetrical, and hybridized to the right half (R) and the left half (L) of lambda DNA with the ratio of R/L=4/1, and they showed a lower hybridizability than the transcripts with native lambda DNA. The initiation sites recognizable by RNA polymerase seemed to be the same on both native and U.V.-irradiated lambda DNA, though the transcription of U.V.-treated lambda DNA appeared to terminate with rather short RNA chains. (author)

Determination of the isotopic ratio 234 U/238 U and 235 U/238 U in uranium commercial reagents by alpha spectroscopy

International Nuclear Information System (INIS)

Iturbe G, J.L.

1990-02-01

In this work the determination of the isotope ratio 234 U/ 238 U and 235 U/ 238 U obtained by means of the alpha spectroscopy technique in uranium reagents of commercial marks is presented. The analyzed uranium reagents were: UO 2 (*) nuclear purity, UO 3 (*) poly-science, metallic uranium, uranyl nitrate and uranyl acetate Merck, uranyl acetate and uranyl nitrate Baker, uranyl nitrate (*) of the Refinement and Conversion Department of the ININ, uranyl acetate (*) Medi-Lab Sigma of Mexico and uranyl nitrate Em Science. The obtained results show that the reagents that are suitable with asterisk (*) are in radioactive balance among the one 234 U/ 238 U, since the obtained value went near to the unit. In the case of the isotope ratio 235 U/ 238 U the near value was also obtained the one that marks the literature that is to say 0.04347, what indicates that these reagents contain the isotope of 235 U in the percentage found in the nature of 0.71%. The other reagents are in radioactive imbalance among the 234 U/ 238 U, the found values fluctuated between 0.4187 and 0.1677, and for the quotient of activities 235 U/ 238 U its were of 0.0226, and the lowest of 0.01084. Also in these reagents it was at the 236 U as impurity. The isotope of 236 U is an isotope produced artificially, for what is supposed that the reagents that are in radioactive imbalance were synthesized starting from irradiated fuel. (Author)

High-pressure synthesis and characterization of new actinide borates, AnB4O8 (An=Th, U).

Science.gov (United States)

Hinteregger, Ernst; Hofer, Thomas S; Heymann, Gunter; Perfler, Lukas; Kraus, Florian; Huppertz, Hubert

2013-11-18

New actinide borates ThB4O8 and UB4O8 were synthesized under high-pressure, high-temperature conditions (5.5 GPa/1100 °C for thorium borate, 10.5 GPa/1100 °C for the isotypic uranium borate) in a Walker-type multianvil apparatus from their corresponding actinide oxide and boron oxide. The crystal structure was determined on basis of single-crystal X-ray diffraction data that were collected at room temperature. Both compounds crystallized in the monoclinic space group C2/c (Z=4). Lattice parameters for ThB4O8: a=1611.3(3), b=419.86(8), c=730.6(2) pm; β=114.70(3)°; V=449.0(2) Å(3); R1=0.0255, wR2=0.0653 (all data). Lattice parameters for UB4O8: a=1589.7(3), b=422.14(8), c=723.4(2) pm; β=114.13(3)°; V=443.1(2) Å(3); R1=0.0227, wR2=0.0372 (all data). The new AnB4O8 (An=Th, U) structure type is constructed from corner-sharing BO4 tetrahedra, which form layers in the bc plane. One of the four independent oxygen atoms is threefold-coordinated. The actinide cations are located between the boron-oxygen layers. In addition to Raman spectroscopic investigations, DFT calculations were performed to support the assignment of the vibrational bands. © 2013 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This isan open access article under the terms of the Creative Commons AttributionLicense, which permits use, distribution and reproduction in any medium,provided the original work is properly cited.

Study of uranium(4) phosphites

International Nuclear Information System (INIS)

Avduevskaya, K.A.; Rozanov, I.A.; Mironova, V.S.

1977-01-01

Neutral and monosubstituted uranium phosphites U(HPO 3 ) 2 x2H 2 O and U(H 2 PO 3 ) 4 x2H 2 O and pyrophosphite U(H 2 P 2 O 5 ) 2 have been separated and identified. Thermal stability of the sepaated compounds have been studied. Upon heating U(HPO 3 )x2H 2 O up to 120-190 deg C, hydrate water is removed. The final product obtained on heating up to 900 deg C is identified as UP 2 O 7 . In the case of U(H 2 PO 3 ) 4 x2H 2 O, crystallization water is removed stepwise within the ranges of 60-140 deg C and 160-270 deg C. Complete removal of water yields a compound of U(H 2 P 2 O 5 ). It has been established that uranium phosphites are isomorphous to the corresponding thorium phosphites

Hydrogen absorption-desorption properties of U2Ti

International Nuclear Information System (INIS)

Yamamoto, Takuya; Tanaka, Satoru; Yamawaki, Michio

1990-01-01

Hydrogen absorption-desorption properties of U 2 Ti intermetallic compound was examined over the temperature range of 298 to 973 K and at hydrogen pressures below 10 5 Pa. It absorbs hydrogen up to 7.6 atoms per F.U. (formula unit) by two step reactions and hence each desorption isotherm is separated into two plateau regions. In the first plateau, a newly-found ternary hydride is formed, where the hydrogen concentration, c H , reaches 2.4 H atoms/F.U. In the second plateau, UH 3 is formed and c H reaches 7.6 H atoms/F.U. The specimen is disintegrated into fine powder in the second plateau, while in the first plateau the ternary hydride which was identified to be UTi 2 H x (x=4.8 to 6.2) showed high durability against powdering. It is predicted that UTi 2 can be suitable material for tritium storage. (orig.)

Energy Level Statistics of SO(5) Limit of Super-symmetry U(6/4) in Interacting Boson-Fermion Model

International Nuclear Information System (INIS)

Bai Hongbo; Zhang Jinfu; Zhou Xianrong

2005-01-01

We study the energy level statistics of the SO(5) limit of super-symmetry U(6/4) in odd-A nucleus using the interacting boson-fermion model. The nearest neighbor spacing distribution (NSD) and the spectral rigidity (Δ 3 ) are investigated, and the factors that affect the properties of level statistics are also discussed. The results show that the boson number N is a dominant factor. If N is small, both the interaction strengths of subgroups SO B (5) and SO BF (5) and the spin play important roles in the energy level statistics, however, along with the increase of N, the statistics distribution would tend to be in Poisson form.

Reduction of UF4 to U metal

International Nuclear Information System (INIS)

Suh, I.S.; Kim, J.H.; Min, B.T.; Whang, S.C.; Im, K.S.

1983-01-01

The operating conditions for the production of uranium metal by reduction of UFsub(4) with magnesium powder have been thoroughly investigated using the reactor 1 Kg nominal capacity. UFsub(4) powders which were produced from the conversion plant in KAERI are used and MgFsub(2), by-product of the reduction, are used as liner after pulverizing. 95% of average yield of uranium metal are obtained with 6% excess of magnesium powder in size of -πo + 50 mesh and its density is 18.5 g/cc, and furthermore the yield is increased when mafnesium powders are used after washed with trichloro-ethylene and dried. (Author)

19 CFR 4.69 - Shipping articles.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 1 2010-04-01 2010-04-01 false Shipping articles. 4.69 Section 4.69 Customs... VESSELS IN FOREIGN AND DOMESTIC TRADES Foreign Clearances § 4.69 Shipping articles. No vessel of the U.S... officer, of the shipping articles agreements, including any seaman's allotment agreement, required by 46 U...

MMP-9, uPA and uPAR proteins expression and its prognostic significance in esophageal squamous cell carcinoma treated by radiotherapy

International Nuclear Information System (INIS)

Zhu Shuchai; Wang Yafei; Su Jingwei; Wang Yuxiang; Shen Wenbin; Li Juan

2008-01-01

Objective: To explore the the prognostic significance of MMP-9, uPA and uPAR protein expression and its relationship with clinical-pathologic factors in esophageal squamous cell carcinoma treated by radiotherapy. Methods: MMP-9, uPA and uPAR protein expression was measured in 59 esophageal carcinomas and 41 peri-carcinoma tissues with immunohistochemistry. The relationship between the protein expression and the clinical-pathological parameters was analyzed, and the prognostic factors in esophageal squamous cell carcinoma treated by radiotherapy alone was evaluated. Results: The rates of positive expression of MMP-9, uPA and uPAR were 85%, 76% and 78% in esophageal carcinoma and 39%, 49% and 44% in peri-carcinoma tissues (χ 2 =22.54, 8.04 and 12.18; P=0.000,0.005 and 0.000). The rates of positive expression of MMP-9 was 79% and 100% when the depth of tumor invasion was ≤2 cm and >2 cm(P= 0.048), respectively. The expression of uPA was significantly correlated with the status of fat interspace between the esophageal lesion and the vertebra in CT scanning image. When the fat interspace existed and disappeared, the rates of strong positive expression was 44% and 70%, respectively (χ 2 =4.21, P=0.040). The positive expression rate of uPA was significantly correlated with distant metastasis, which was 100% in patients with distant metastasis and 68.89% in those without distant metastasis(χ 2 =4.12, P=0.042). The positive expression rate of MMP-9, uPA and uPAR did not affect the prognosis and the short-term result of esophageal carcinoma treated by radiotherapy alone. Conclusions: The protein expression of MMP-9, uPA and uPAR may correlate with local infiltration and distant metastasis in esophageal squamous cell carcinoma. Protein expression may not influence the prognosis of esophageal carcinoma treated by radio therapy, though long time followed-up is still needed. (authors)

Π4U: A high performance computing framework for Bayesian uncertainty quantification of complex models

Science.gov (United States)

Hadjidoukas, P. E.; Angelikopoulos, P.; Papadimitriou, C.; Koumoutsakos, P.

2015-03-01

We present Π4U, an extensible framework, for non-intrusive Bayesian Uncertainty Quantification and Propagation (UQ+P) of complex and computationally demanding physical models, that can exploit massively parallel computer architectures. The framework incorporates Laplace asymptotic approximations as well as stochastic algorithms, along with distributed numerical differentiation and task-based parallelism for heterogeneous clusters. Sampling is based on the Transitional Markov Chain Monte Carlo (TMCMC) algorithm and its variants. The optimization tasks associated with the asymptotic approximations are treated via the Covariance Matrix Adaptation Evolution Strategy (CMA-ES). A modified subset simulation method is used for posterior reliability measurements of rare events. The framework accommodates scheduling of multiple physical model evaluations based on an adaptive load balancing library and shows excellent scalability. In addition to the software framework, we also provide guidelines as to the applicability and efficiency of Bayesian tools when applied to computationally demanding physical models. Theoretical and computational developments are demonstrated with applications drawn from molecular dynamics, structural dynamics and granular flow.

Π4U: A high performance computing framework for Bayesian uncertainty quantification of complex models

International Nuclear Information System (INIS)

Hadjidoukas, P.E.; Angelikopoulos, P.; Papadimitriou, C.; Koumoutsakos, P.

2015-01-01

We present Π4U, 1 an extensible framework, for non-intrusive Bayesian Uncertainty Quantification and Propagation (UQ+P) of complex and computationally demanding physical models, that can exploit massively parallel computer architectures. The framework incorporates Laplace asymptotic approximations as well as stochastic algorithms, along with distributed numerical differentiation and task-based parallelism for heterogeneous clusters. Sampling is based on the Transitional Markov Chain Monte Carlo (TMCMC) algorithm and its variants. The optimization tasks associated with the asymptotic approximations are treated via the Covariance Matrix Adaptation Evolution Strategy (CMA-ES). A modified subset simulation method is used for posterior reliability measurements of rare events. The framework accommodates scheduling of multiple physical model evaluations based on an adaptive load balancing library and shows excellent scalability. In addition to the software framework, we also provide guidelines as to the applicability and efficiency of Bayesian tools when applied to computationally demanding physical models. Theoretical and computational developments are demonstrated with applications drawn from molecular dynamics, structural dynamics and granular flow

TIME SERIES MODELS OF THREE SETS OF RXTE OBSERVATIONS OF 4U 1543–47

International Nuclear Information System (INIS)

Koen, C.

2013-01-01

The X-ray nova 4U 1543–47 was in a different physical state (low/hard, high/soft, and very high) during the acquisition of each of the three time series analyzed in this paper. Standard time series models of the autoregressive moving average (ARMA) family are fitted to these series. The low/hard data can be adequately modeled by a simple low-order model with fixed coefficients, once the slowly varying mean count rate has been accounted for. The high/soft series requires a higher order model, or an ARMA model with variable coefficients. The very high state is characterized by a succession of 'dips', with roughly equal depths. These seem to appear independently of one another. The underlying stochastic series can again be modeled by an ARMA form, or roughly as the sum of an ARMA series and white noise. The structuring of each model in terms of short-lived aperiodic and 'quasi-periodic' components is discussed.

Review of the early AP penetrator work at LASL which led to the selection of U-3/4 Ti alloy

International Nuclear Information System (INIS)

Sandstrom, D.J.

1976-01-01

A historical review is presented of the depleted uranium penetrator work. The following alloys were studied: U--Ti, U--Mo, U--Nb, and U--Nb--Ti. Ballistic properties, armor penetration, and corrosion resistance were studied. The U--Ti alloy was found to offer the best combination of properties. 12 figures

Beta decay heat following U-235, U-238 and Pu-239 neutron fission

Science.gov (United States)

Li, Shengjie

1997-09-01

This is an experimental study of beta-particle decay heat from 235U, 239Pu and 238U aggregate fission products over delay times 0.4-40,000 seconds. The experimental results below 2s for 235U and 239Pu, and below 20s for 238U, are the first such results reported. The experiments were conducted at the UMASS Lowell 5.5-MV Van de Graaff accelerator and 1-MW swimming-pool research reactor. Thermalized neutrons from the 7Li(p,n)7Be reaction induced fission in 238U and 239Pu, and fast neutrons produced in the reactor initiated fission in 238U. A helium-jet/tape-transport system rapidly transferred fission fragments from a fission chamber to a low background counting area. Delay times after fission were selected by varying the tape speed or the position of the spray point relative to the beta spectrometer that employed a thin-scintillator-disk gating technique to separate beta-particles from accompanying gamma-rays. Beta and gamma sources were both used in energy calibration. Based on low-energy(energies 0-10 MeV. Measured beta spectra were unfolded for their energy distributions by the program FERD, and then compared to other measurements and summation calculations based on ENDF/B-VI fission-product data performed on the LANL Cray computer. Measurements of the beta activity as a function of decay time furnished a relative normalization. Results for the beta decay heat are presented and compared with other experimental data and the summation calculations.

Cooling rates and the depth of detachment faulting at oceanic core complexes: Evidence from zircon Pb/U and (U-Th)/He ages

Science.gov (United States)

Grimes, Craig B.; Cheadle, Michael J.; John, Barbara E.; Reiners, P.W.; Wooden, J.L.

2011-01-01

Oceanic detachment faulting represents a distinct mode of seafloor spreading at slow spreading mid-ocean ridges, but many questions persist about the thermal evolution and depth of faulting. We present new Pb/U and (U-Th)/He zircon ages and combine them with magnetic anomaly ages to define the cooling histories of gabbroic crust exposed by oceanic detachment faults at three sites along the Mid-Atlantic Ridge (Ocean Drilling Program (ODP) holes 1270D and 1275D near the 15??20???N Transform, and Atlantis Massif at 30??N). Closure temperatures for the Pb/U (???800??C-850??C) and (U-Th)/He (???210??C) isotopic systems in zircon bracket acquisition of magnetic remanence, collectively providing a temperature-time history during faulting. Results indicate cooling to ???200??C in 0.3-0.5 Myr after zircon crystallization, recording time-averaged cooling rates of ???1000??C- 2000??C/Myr. Assuming the footwalls were denuded along single continuous faults, differences in Pb/U and (U-Th)/He zircon ages together with independently determined slip rates allow the distance between the ???850??C and ???200??C isotherms along the fault plane to be estimated. Calculated distances are 8.4 ?? 4.2 km and 5.0 2.1 km from holes 1275D and 1270D and 8.4 ?? 1.4 km at Atlantis Massif. Estimating an initial subsurface fault dip of 50 and a depth of 1.5 km to the 200??C isotherm leads to the prediction that the ???850??C isotherm lies ???5-7 km below seafloor at the time of faulting. These depth estimates for active fault systems are consistent with depths of microseismicity observed beneath the hypothesized detachment fault at the TAG hydrothermal field and high-temperature fault rocks recovered from many oceanic detachment faults. Copyright 2011 by the American Geophysical Union.

HIGH ANGULAR RESOLUTION MULTI-LINE STUDY OF HH 1 AND 2

Energy Technology Data Exchange (ETDEWEB)

Raga, A. C.; Castellanos-Ramírez, A. [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Ap. 70-543, 04510 D.F., México (Mexico); Reipurth, Bo; Chiang, Hsin-Fang [Institute for Astronomy, University of Hawaii at Manoa, Hilo, HI 96720 (United States); Bally, J., E-mail: raga@nucleares.unam.mx [Center for Astrophysics and Space Astronomy, University of Colorado, UCB 389, Boulder, CO 80309 (United States)

2015-10-15

We present new Hubble Space Telescope (HST) narrow band images of the bright Herbig–Haro (HH) objects HH 1 and 2 in the light of the Hα, Hβ, [O i] 6300, [O ii] 3726+28, [O iii] 5007 and [S ii] 6716+30 emission lines. The resulting emission and line ratio maps give an improved picture of the physical structure of these HH objects, showing the presence of spatially limited, high excitation/ionization ridges. We find that HH 1 has a morphology that could be interpreted in terms of a single, asymmetric bow shock, and that many of the clumps of HH 2 fall in two bow-shaped structures of different excitations. We also construct two-line ratio plots showing clear trends, which are much simpler than the highly complex spatial distributions of the emission, and are therefore interesting for testing shock models of HH objects (we only present a comparison with previously published, steady plane-parallel shock models). We have also used the temperature-sensitive [O i]/[S ii] line ratio to evaluate the temperature range and to obtain temperature maps of HH 1 and 2. We find that this line ratio picks out emitting regions with temperatures ≈10{sup 4} K, except along the leading edges of the HH 1 and 2 bow shocks (in which temperatures of ∼3 → 5 × 10{sup 4} K are obtained)

First-in-human uPAR PET

DEFF Research Database (Denmark)

Persson, Morten; Skovgaard, Dorthe; Brandt-Larsen, Malene

2015-01-01

A first-in-human clinical trial with Positron Emission Tomography (PET) imaging of the urokinase-type plasminogen activator receptor (uPAR) in patients with breast, prostate and bladder cancer, is described. uPAR is expressed in many types of human cancers and the expression is predictive...... for targeted molecular imaging with PET. The safety, pharmacokinetic, biodistribution profile and radiation dosimetry after a single intravenous dose of (64)Cu-DOTA-AE105 were assessed by serial PET and computed tomography (CT) in 4 prostate, 3 breast and 3 bladder cancer patients. Safety assessment...... of invasion, metastasis and indicates poor prognosis. uPAR PET imaging therefore holds promise to be a new and innovative method for improved cancer diagnosis, staging and individual risk stratification. The uPAR specific peptide AE105 was conjugated to the macrocyclic chelator DOTA and labeled with (64)Cu...

238U (n,f) measurements below 30 keV

International Nuclear Information System (INIS)

Slovacek, R.E.; Cramer, D.S.; Bean, E.B.; Hockenbury, R.W.; Valentine, J.R.; Block, R.C.

1975-01-01

The 238 U (n,f) cross section has been measured from 3 eV to about 30 keV with the lead slowing down spectrometer at the RPI Linac. Four fission ionization chambers containing a total of about 0.8 gm of 238 U (4.1 ppm 235 U) were used for the measurements. The fission widths of the 6.67, 20.9, and the 36.8 eV resonances were measured as (10 +- 1), (58 +- 9), and (12 +- 2) nanoelectron-volts respectively. The fission cross section integrated over the two subthreshold groups at 720 and 1210 eV and the average fission cross section from 10 to 30 keV are in agreement with a previous time of flight measurement. The fission width at 6.67 eV is 20 times smaller than an upper limit set by the only reported measurement in this energy region; the fission widths obtained in the present investigation are consistent with the (30 +- 50) nanoelectronvolt average width previously obtained for the resonances between 37 and 327 eV in a time of flight measurement using a nuclear device. From the measured fission widths, the 238 U thermal fission cross section was determined to be 2.7 +- 0.3 μ barns. The resonance fission integral was also obtained from the data as 1.33 +- 0.15 mbarns for 238 U. (4 figures, 4 tables) (U.S.)

Transuranium element incorporation into the β-U3O8 uranyl sheet

International Nuclear Information System (INIS)

Miller, M.L.; Burns, P.C.; Ewing, R.C.; Finch, R.J.

1997-01-01

Spent nuclear fuel (SNF) is unstable under oxidizing conditions. Although recent studies have determined the paragenetic sequence for uranium phases that result from the corrosion of SNF, there are only limited data on the potential of alteration phases for the incorporation of transuranium elements. The crystal chemical characteristics of transuranic elements (TUE) are to a certain extent similar to uranium; thus TUE incorporation into the sheets of uranyl oxide hydrate structures can be assessed by examination of the structural details of the β-U 3 O 8 sheet type. The sheets of uranyl polyhedra observed in the crystal structure of β-U 3 O 8 also occur in the mineral billietite, where they alternate with α-U 3 O 8 type sheets. Preliminary crystal structure determinations for the minerals ianthinite, and wyartite, indicate that these phases also contain β-U 3 O 8 type sheets. The β-U 3 O 8 sheet anion topology contains triangular, rhombic, and pentagonal sites in the proportions 2:1:2. In all structures containing β-U 3 O 8 type sheets, the triangular sites are vacant. The pentagonal sites are filled with U 6+ O 2 forming pentagonal bipyramids. The rhombic dipyramids filling the rhombic sites contain U 6+ O 2 in billietite, U 4+ O 2 in β-U 3 O 8 , U 4+ (H 2 O) 2 in ianthinite, and U 4+ O 3 in wyartite-II. Interlayer species include: H 2 O (billietite, wyartite II, and ianthinite), Ba 2+ (billietite) Ca 2+ wyartite II, and Co 3 2- wyartite II; there is no interlayer in β-U 3 O 8 . The similarity of known TUE coordination polyhedra with those of U suggests that the β-U 3 O 8 sheet will accommodate TUE substitution coupled with variations in apical anion configuration and interlayer population providing the required charge balance

Inventory of U.S. 2012 dioxin emissions to atmosphere.

Science.gov (United States)

Dwyer, Henri; Themelis, Nickolas J

2015-12-01

In 2006, the U.S. EPA published an inventory of dioxin emissions for the U.S. covering the period from 1987-2000. This paper is an updated inventory of all U.S. dioxin emissions to the atmosphere in the year 2012. The sources of emissions of polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), collectively referred to in this paper as "dioxins", were separated into two classes: controlled industrial and open burning sources. Controlled source emissions decreased 95.5% from 14.0 kg TEQ in 1987 to 0.6 kg in 2012. Open burning source emissions increased from 2.3 kg TEQ in 1987 to 2.9 kg in 2012. The 2012 dioxin emissions from 53 U.S. waste-to-energy (WTE) power plants were compiled on the basis of detailed data obtained from the two major U.S. WTE companies, representing 84% of the total MSW combusted (27.4 million metric tons). The dioxin emissions of all U.S. WTE plants in 2012 were 3.4 g TEQ and represented 0.54% of the controlled industrial dioxin emissions, and 0.09% of all dioxin emissions from controlled and open burning sources. Copyright © 2015. Published by Elsevier Ltd.

Post-irradiation analysis of low enriched U-Mo/Al dispersions fuel miniplate tests, RERTR 4 and 5

International Nuclear Information System (INIS)

Hofman, G.L.; Finlay, M.R.; Kim, Y.S.

2005-01-01

Interpretation of the post irradiation data of U-Mo/Al dispersion fuel mini plates irradiated in the Advanced Test Reactor to a maximum U-235 burn up of 80% are presented. The analyses addresses fuel swelling and porosity formation as these fuel performance issues relate to fuel fabrication and irradiation parameters. Specifically, mechanisms involved in the formation of porosity observed in the U-Mo/Al interaction phase are discussed and, means of mitigating or eliminating this irradiation phenomenon are offered. (author)

Impact of uranium (U) on the cellular glutathione pool and resultant consequences for the redox status of U.

Science.gov (United States)

Viehweger, Katrin; Geipel, Gerhard; Bernhard, Gert

2011-12-01

Uranium (U) as a redox-active heavy metal can cause various redox imbalances in plant cells. Measurements of the cellular glutathione/glutathione disulfide (GSH/GSSG) by HPLC after cellular U contact revealed an interference with this essential redox couple. The GSH content remained unaffected by 10 μM U whereas the GSSG level immediately increased. In contrast, higher U concentrations (50 μM) drastically raised both forms. Using the Nernst equation, it was possible to calculate the half-cell reduction potential of 2GSH/GSSG. In case of lower U contents the cellular redox environment shifted towards more oxidizing conditions whereas the opposite effect was obtained by higher U contents. This indicates that U contact causes a consumption of reduced redox equivalents. Artificial depletion of GSH by chlorodinitrobenzene and measuring the cellular reducing capacity by tetrazolium salt reduction underlined the strong requirement of reduced redox equivalents. An additional element of cellular U detoxification mechanisms is the complex formation between the heavy metal and carboxylic functionalities of GSH. Because two GSH molecules catalyze electron transfers each with one electron forming a dimer (GSSG) two UO(2) (2+) are reduced to each UO(2) (+) by unbound redox sensitive sulfhydryl moieties. UO(2) (+) subsequently disproportionates to UO(2) (2+) and U(4+). This explains that in vitro experiments revealed a reduction to U(IV) of only around 33% of initial U(VI). Cellular U(IV) was transiently detected with the highest level after 2 h of U contact. Hence, it can be proposed that these reducing processes are an important element of defense reactions induced by this heavy metal.

Dicty_cDB: Contig-U15069-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available Contig-U15069-1 no gap 1241 1 2719927 2720886 PLUS 37 43 U15069 16 2 0 0 0 5 8 0 0 1 1 0 4 0 Show Contig...-U15069-1 Contig ID Contig-U15069-1 Contig update 2004. 6.11 Contig sequence >Contig-U15069-1 (Contig...-U15069-1Q) /CSM_Contig/Contig-U15069-1Q.Seq.d TTTCAAACCAAAACATAAAATAATTAAAAATGACAACTGTTAAACCA...AAAAATAAAATAAATAAAAATAGTTTTAAA Gap no gap Contig length 1241 Chromosome number (1..6, M) 1 Chromosome length...07Z ,263,623 est42= VSJ431Z ,390,646 est43= CHB363Z ,460,1187 Translated Amino Acid sequence snqnik*lkmttvkptspenprvffditig

Biological availability of 238U, 234U and 226Ra for wild berries and meadow grasses in natural ecosystems of Belarus

International Nuclear Information System (INIS)

Sokolik, G.A.; Ovsiannikova, S.V.; Voinikava, K.V.; Ivanova, T.G.; Papenia, M.V.

2014-01-01

This work is devoted to investigation of behavior of 234 U, 238 U and 226 Ra by determining the soil to plant transfer under different natural conditions such as forest or swamped areas and meadow lands with different soil types. The paper summarizes the data on investigation of uranium and radium uptake by wild berries and natural meadow grasses in the typical conditions of Belarus. Parameters characterizing the biological availability of 234 U, 238 U and 226 Ra for bilberry (Vaccinium myrtillus), lingonberry (Vaccinium viti-idaea), blueberry (Vaccinium iliginosum) and cranberry (Vaccinium oxycoccus palustris) as well as for widely occurring mixed meadow vegetation, which belongs to the sedge-grass or grass-sedge associations and forbs, have been established. In the sites under investigation, the deposition levels of 238+239+240 Pu were less than 0.37 kBq m −2 and 137 Cs deposition ranged between less than 0.37 and 37 kBq m −2 . It was found that activity concentrations of radionuclides in berries varied in the ranges of 0.037–0.11 for 234 U, 0.036–0.10 for 238 U and 0.11–0.43 Bq kg −1 for 226 Ra, but in the mixed meadow grasses they were 0.32–4.4, 0.24–3.9 and 0.14–6.9 Bq kg −1 accordingly. The 234 U/ 238 U activity ratios were 1.02 ± 0.01 for wild berries, 1.20 ± 0.09 for underground meadow grasses and 1.02 ± 0.02 for proper soils. The concentration ratios (CRs, dry weight basis) of 234 U and 238 U for mixed meadow grasses were 0.036–0.42 and 0.041–0.46 respectively. The correspondent geometric means (GM) were 0.13 and 0.15 with geometric standard deviations (GSD) of 2.4. The CRs of 226 Ra for meadow grasses were 0.031–1.0 with GM 0.20 and GSD 2.6. The CRs of 234 U, 238 U and 226 Ra for wild berries ranged within 0.0018–0.008 (GM is 0.0034, GSD is 1.8), 0.0018–0.008 (GM is 0.0035, GSD is 1.8) and 0.005–0.033 (GM is 0.016, GSD is 2.1) accordingly. The highest CR values of uranium for mixed meadow grasses were found in the sites

Study of 236U/238U ratio at CIRCE using a 16-strip silicon detector with a TOF system

Science.gov (United States)

De Cesare, M.; De Cesare, N.; D'Onofrio, A.; Gialanella, L.; Terrasi, F.

2015-04-01

Accelerator Mass Spectrometry (AMS) is presently the most sensitive technique for the measurement of long-lived actinides, e.g. 236U and xPu isotopes. A new actinide AMS system, based on a 3-MV pelletron tandem accelerator, is operated at the Center for Isotopic Research on Cultural and Environmental Heritage (CIRCE) in Caserta, Italy. In this paper we report on the procedure adopted to increase the 236U abundance sensitivity as low as possible. The energy and position determinations of the 236U ions, using a 16-strip silicon detector have been obtained. A 236U/238U isotopic ratio background level of about 2.9×10-11 was obtained, summing over all the strips, using a Time of Flight-Energy (TOF-E) system with a 16-strip silicon detector (4.9×10-12 just with one strip).

Stationary high confinement plasmas with large bootstrap current fraction in JT-60U

International Nuclear Information System (INIS)

Sakamoto, Y.; Fujita, T.; Ide, S.; Isayama, A.; Takechi, M.; Suzuki, T.; Takenaga, H.; Oyama, N.; Kamada, Y.

2005-01-01

This paper reports the results of the progress in stationary discharges with a large bootstrap current fraction in JT-60U towards steady-state tokamak operation. In the weak shear plasma regime, high-β p ELMy H-mode discharges have been optimized under nearly full non-inductive current drive conditions by the large bootstrap current fraction (f BS ∼ 45%) and the beam driven current fraction (f BD ∼ 50%), which was sustained for 5.8 s in the stationary condition. This duration corresponds to ∼26τ E and ∼2.8τ R , which was limited by the pulse length of negative-ion-based neutral beams. The high confinement enhancement factor H 89 ∼ 2.2 (HH 98y2 ∼ 1.0) was obtained and the profiles of current and pressure reached the stationary condition. In the reversed shear plasma regime, a large bootstrap current fraction (f BS ∼ 75%) has been sustained for 7.4 s under nearly full non-inductive current drive conditions. This duration corresponds to ∼16τ E and ∼2.7τ R . The high confinement enhancement factor H 89 ∼ 3.0 (HH 98y2 ∼ 1.7) was also sustained, and the profiles of current and pressure reached the stationary condition. The large bootstrap current and the off-axis beam driven current sustained this reversed q profile. This duration was limited only by the duration of the neutral beam injection

Joint U. S. --U. S. S. R. test of U. S. MHD electrode systems in U. S. S. R. U-02 MHD facility (phase I). Final report

Energy Technology Data Exchange (ETDEWEB)

Hosler, W R [ed.

1976-01-01

The first (Phase I) joint U.S.-U.S.S.R. test of U.S. electrode materials was carried out in Moscow between September 25 and October 8, 1975 in the Soviet U-02 MHD facility. The test procedure followed closely a predetermined work plan designed to test five different zirconia based materials and the cathode and anode electrode wall modules under MHD operating conditions. The materials which were selected were 88Zr0/sub 2/-12Y/sub 2/0/sub 3/, 82Zr0/sub 2/-18Ce02, 50Zr0/sub 2/-50Ce0/sub 2/, 25Zr0/sub 2/-75Ce0/sub 2/ and 20Zr0/sub 2/-78Ce0/sub 2/-2Ta/sub 2/0/sub 5/. The electrode modules were constructed by Westinghouse Research and Development Laboratory. Each of the five electrode materials had four different current densities established between the anode and cathode during the experiment which lasted a total of 127 hours. There were four main phases in the test schedule: (1) start-up of the channel over a specific heating period. No seed (K/sub 2/C0/sub 3/) introduction - 18 hours. (2) Electrical tests at operating temperature to investigate electro-physical characteristics of the channel and electrodes - 6 hours. (3) Operating life test - 94 hours. (4) Shut-down of the channel over a specific cool down period - 9 hours. All except six electrode pairs performed satisfactorily during the entire test. These were the pairs which were designated to carry maximum or near maximum current density. Five pairs failed early in the life test and the sixth pair failed in the last several hours. Failure was not due to the electrode materials, however, but due to lead-out melting caused by joule heating in the platinum wires. The U-02 facility is described and the operational parameters are given for each phase of the test. The electrode and insulating walls are described and the appropriate parameters that are used to predict the performance of the module are given.

Microstructure of the irradiated U 3Si 2/Al silicide dispersion fuel

Science.gov (United States)

Gan, J.; Keiser, D. D.; Miller, B. D.; Jue, J.-F.; Robinson, A. B.; Madden, J. W.; Medvedev, P. G.; Wachs, D. M.

2011-12-01

The silicide dispersion fuel of U 3Si 2/Al is recognized as the best performance fuel for many nuclear research and test reactors with up to 4.8 gU/cm 3 fuel loading. An irradiated U 3Si 2/Al dispersion fuel ( 235U ˜ 75%) from the high-flux side of a fuel plate (U0R040) from the Reduced Enrichment for Research and Test Reactors (RERTR)-8 test was characterized using transmission electron microscopy (TEM). The fuel was irradiated in the Advanced Test Reactor (ATR) for 105 days. The average irradiation temperature and fission density of the U 3Si 2 fuel particles for the TEM sample are estimated to be approximately 110 °C and 5.4 × 10 27 f/m 3. The characterization was performed using a 200-kV TEM. The U/Si ratio for the fuel particle and (Si + Al)/U for the fuel-matrix-interaction layer are approximately 1.1 and 4-10, respectively. The estimated average diameter, number density and volume fraction for small bubbles (<1 μm) in the fuel particle are ˜94 nm, 1.05 × 10 20 m -3 and ˜11%, respectively. The results and their implication on the performance of the U 3Si 2/Al silicide dispersion fuel are discussed.