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An evaluation of the Nb-93(n,n prime )Nb-93m dosimeter reaction for ENDF/B-VI

Description: The Nb-93(n,n{prime})Nb-93m reaction plays an important role in nuclear energy applications. Because of its low threshold energy and relatively long half-life, it is a desirable reaction for long-term neutron fluence dosimetry in nuclear fission reactors. An evaluation of the differential cross section for this reaction was completed in 1985 by this laboratory as part of a comprehensive effort involving all neutron cross sections for niobium. The objective was to provide input for ENDF/B-VI. It… more
Date: November 1, 1990
Creator: Smith, D. L. & Geraldo, L. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radiation-induced mesotheliomas in rats

Description: Mesotheliomas have been reported in rats that inhaled plutonium, but these tumors have not been extensively studied. To investigate a possible role for inhaled radionuclides in the induction of mesotheliomas, four life-span studies conducted at the Inhalation Toxicology Research Institute are reviewed. A total of 3076 F344 rats were exposed by inhalation to aerosols of {sup 239}PuO{sub 2}, mixed uranium-plutonium oxide, or {sup 144}CeO{sub 2}. Results showed that a low incidence of pleural meso… more
Date: January 1, 1990
Creator: Hahn, F. F.; Haley, P. J.; Hubbs, A. F.; Hoover, M. D. & Lundgren, D. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Double beta decay of U-238

Description: During the last period, two samples of 33 yr old uranyl nitrate have been examined for the accumulation of Pu-238 formed as a result of double beta decay. The 2.5 kg sample has led only to an upper limit of 6 {times} 10{sup 20} yr. The 8.5 kg sample has produced positive results corresponding to a half-life of 2 {times} 10{sup 21 } yr. The possibility of contaminating nuclear reactions has been carefully examined and eliminated. The possibility that contamination may have been introduced by the… more
Date: November 1, 1990
Creator: Turkevich, A. & Economou, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Safety and environmental aspects of HYLIFE-II

Description: The HYLIFE-II inertial confinement fusion reactor uses a Flibe spray for blast chamber protection and tritium breeding. HYLIFE-II is passively safe, having no large sources of energy available to disperse radioactive materials. The dominant activation product is {sup 18}F (half-life 110 minutes). Only a small fraction (< 10{sup {minus}5}) of the Flibe activation products would be mobilized. The offsite dose from a severe accident involving simultaneous failure of the blast chamber and containme… more
Date: January 1, 1990
Creator: Dolan, T.J. & Longhurst, G.R. (Idaho National Engineering Lab., Idaho Falls, ID (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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sup 176 Lu: An unreliable s-process chronometer

Description: A level scheme of {sup 176}Lu up to {approximately}1400 keV excitation energy is deduced from a gamma-gamma coincidence experiment and previously published particle transfer data. 170 gamma-ray transitions are placed between 85 levels, confirming many of the previously established levels and some of the decay scheme. A level at 835.5 keV (J{sup {pi}} = 5{sup {minus}}, t{sub 1/2} < 10 ns) decays with substantial strength to both the ground state (7{sup {minus}}, 4.08 {times} 10{sup 10} yr) and t… more
Date: November 1, 1990
Creator: Lesko, K.T.; Norman, E.B.; Larimer, R.M. & Sur, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An interesting finding in sup 229 Th

Description: Work at INEL has recently established that the first excited states of {sup 229}Th forms a closely spaced doublet with the ground state, the separation being 1 {plus minus} 4 electron volts. A discussion of the data and the reasoning supporting this unprecedented finding is given. Some potential applications are briefly mentioned. 27 refs., 3 figs., 2 tabs.
Date: January 1, 1990
Creator: Reich, C.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Precision measurement of the half-life of sup 56 Co

Description: Gamma rays from a mixed source of {sup 56}Co + {sup 46}Sc were measured in a Ge(Li) detector. The {sup 56}Co/{sup 46}Sc intensity ratios I{sub 847}/I{sub 889} were determined by careful analysis of line shapes and underlying backgrounds. Based on the known {sup 46}Sc adopted half-life value of 83.810(10) d, the fit to the intensity ratios corrected for {sup 46}Sc decay from 107 runs over an elapsed time of 172 days gave a half-life of 77.29(3) d. By combining this result with other published da… more
Date: January 1, 1990
Creator: Alburger, D.E. (Brookhaven National Lab., Upton, NY (USA)) & Wesselborg, C. (Brookhaven National Lab., Upton, NY (USA) Giessen Univ. (Germany, F.R.). Inst. fuer Kernphysik)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The double beta decay spectrum of sup 100 Mo as measured with a TPC (time projection chamber)

Description: A time projection chamber with 8.3 grams of enriched {sup 100}MoO{sub 3} as the central electrode has been operating approximately five months in an underground laboratory. A preliminary analysis of the two-electron sum energy spectrum, the spectrum of those same electrons taken singly, and the opening angle distribution yields a half life of 1.16{sub -0.08}{sup +0.34} {times} 10{sup 19} y at the 68% confidence level for two-neutrino double beta decay of {sup 100}Mo. 9 refs., 8 figs.
Date: January 1, 1990
Creator: Elliott, S. R.; Moe, M. K.; Nelson, M. A. & Vient, M. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Test of pre-ENDF/B-VI decay data and fission yields

Description: Pre-ENDF/B-VI nuclear decay data and fission yields have been supplemented by average beta and gamma energies and Pn-values from recent experiments at Studsvik. This data base has been used for a series of summation calculations, and the results have been compared with experimental determinations of decay heat and of delayed-neutron effects. The comparisons are limited to thermal fission of {sup 235}U and {sup 239}Pu and to fast fission of {sup 238}U. The general impression of the comparisons i… more
Date: October 1, 1990
Creator: Rudstam, G. & England, T. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The synthetic elements

Description: Prior to 1940, the heaviest element known was uranium, discovered in 1789. Since that time the elements 93 through 109 have been synthesized and identified and the elements 43, 61, 85, and 87 which were missing form the periodic tables of the 1930's have been discovered. The techniques and problems involved in these discoveries and the placement of the transuranium elements in the periodic table will be discussed. The production and positive identification of elements heavier than Md (Z=101), w… more
Date: May 1, 1990
Creator: Hoffman, D.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Spectroscopic studies near the proton drip line

Description: We have investigated nuclei close to the proton drip line by using heavy-ion fusion reactions to produce extremely neutron-deficient nuclides. Their nuclear decay properties were studied by using on-line isotope separators at Oak Ridge (UNISOR) and Berkeley (OASIS), the Oak Ridge National Laboratory velocity filter, and a fast helium-gas-jet transport system at Lawrence Berkeley Laboratory 88-Inch Cyclotron. Many isotopes, isomers, and {beta}-delayed-proton and {alpha}-particle emitters were di… more
Date: January 1, 1990
Creator: Toth, K.S. (Oak Ridge National Lab., TN (USA)); Moltz, D.M.; Nitschke, J.M.; Wilmarth, P.A. (Lawrence Berkeley Lab., CA (USA)) & Robertson, J.D. (Kentucky Univ., Lexington, KY (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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In vivo metabolism of I-123 labeled semisynthetic low density lipoproteins

Description: We previously observed that small model beta-strand peptides (MBPs) selectively bind to human low density lipoprotein (hLDL) in vitro, and that some MBPs can be labeled with I-123-tyramine cellobiose (I-123-TyC). We hypothesized that metabolism of semisynthetic hLDL should mimic that of covalently labeled native hLDL, and planned to evaluate the biodistribution in rabbits of semisynthetic hLDL; to determine effects of prior oxidation and acetylation of the adsorbing hLDL on binding of MBPs and … more
Date: December 1, 1990
Creator: Harper, Paul V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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In vivo metabolism of I-123 labeled semisynthetic low density lipoproteins. Final technical report, September 28, 1988--September 27, 1990

Description: We previously observed that small model beta-strand peptides (MBPs) selectively bind to human low density lipoprotein (hLDL) in vitro, and that some MBPs can be labeled with I-123-tyramine cellobiose (I-123-TyC). We hypothesized that metabolism of semisynthetic hLDL should mimic that of covalently labeled native hLDL, and planned to evaluate the biodistribution in rabbits of semisynthetic hLDL; to determine effects of prior oxidation and acetylation of the adsorbing hLDL on binding of MBPs and … more
Date: December 1, 1990
Creator: Harper, Paul V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A new method for picosecond lifetime measurements using electronic timing: Nuclear structure applications

Description: A technique to measure the lifetimes of nuclear states with half lives <10 ps has been developed in conjunction with the TRISTAN mass separator at the High Flux Beam Reactor at BNL. The method uses fast plastic and BaF{sub 2} scintillators and Ge detectors in a triple coincidence ({beta}-{gamma}-{gamma}) fast-slow counting system. The timing information is derived from the fast plastic-BaF{sub 2} coincidence, while the higher resolution of the Ge detector (in slow coincidence) serves to insure … more
Date: January 1, 1990
Creator: Gill, R.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Single particle states in the heaviest known nuclei

Description: Neutron single-particle states above the N=152 subshell have been studied by high-resolution (d,p) reaction on a {sup 250}Cf target. All of the orbitals between N=152 and N=164 subshells have been identified. A tentative assignment has been made for the 1/2-(750) Nilsson state. 10 refs.
Date: January 1, 1990
Creator: Ahmad, I.; Chasman, R.R.; Friedman, A.M. (Argonne National Lab., IL (USA)) & Yates, S.W. (Kentucky Univ., Lexington, KY (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Characteristics of the samples in the FNG fission deposit collection

Description: Information concerning the samples in the Fast Neutron Generator (FNG) Group's fission deposit collection has been assembled. This includes the physical dimensions, isotopic analyses, half-lives, alpha emission rates specific activities and deposit weights. 10 refs., 9 figs., 5 tabs.
Date: December 1, 1990
Creator: Meadows, J. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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In-vivo measurements of Pb-210 to determine cumulative exposure to radon daughters: A pilot study

Description: The feasibility of measuring Pb-210 in vivo in the skulls of those individuals who have resided in homes with above average levels of radon/radon daughters, has now been successfully demonstrated. These values, when incorporated into metabolic models of Pb-210 in the body including other related physical parameters, can be used for the calculation of a realistic estimate of a resident's cumulative exposure to radon and its' decay products. Data are presented for 26 subjects exposed to higher th… more
Date: October 1, 1990
Creator: Laurer, G.R.; Cohen, N. (New York Univ., Tuxedo, NY (USA). Inst. of Environmental Medicine); Stark, A. & Ju, C. (New York State Dept. of Health, Albany, NY (USA). Bureau of Environmental and Occupational Epidemiology)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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