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Determination of the half-life of^(184g)Re and the isomeric ratio of^(184m,g)Re induced by D-T neutrons

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Chinese Physics C 2022年第11期46卷 168-176页

作者：兰长林魏玉婷王家豪杨宪林姜功葛裕杰徐超冯蠡李小军 School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China

The isomeric ratio of^(184m,g)Re and the half-life of^(184g)Re were measured in the ^(185)Re(n,2n)^(184)Re reaction at 14.8 MeV,and the uncertainty was discussed in detail.The measurements were performed using the activation method implemented for a rhenium sample using the K-400 neutron generator at the Chinese Academy of Engineering Physics(CAEP).isomeric state and ground state nuclei of ^(184)Re were identified by their γ-ray spectra.To eliminate the effect of the γ-ray emitted from the isomer on the counting of the ground state characteristic peaks,the isomeric ratio of^(184m,g)Re was calculated to be 0.29±0.11 according to the neutron activation cross-section formula.This result is consistent with previous data within the uncertainty and can be used to determine parameters that characterize the dependence of the level density on the excitation energy and angular momentum.Through exponential function fitting and a detailed discussion of the uncertainty evaluation,the half-life of^(184g)Re was determined as 35.43±0.16 d,which is consistent with the currently recommended value;however,the uncertainty assessment of the latter was barely documented.In addition,this study indicates that the half-life of the ground state can be obtained by eliminating the contamination of γ-rays emitted from the isomer,which provides the possibility of determining the half-lives of nuclides containing isomers.

关键词： Half-life ^(184)Re γ-ray spectrometry isomeric ratio

Interaction of photons with silver and indium nuclei at energies up to 20 MeV

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Chinese Physics C 2024年第2期48卷 135-140页

作者： J.H.Khushvaktov M.A.Demichev D.L.Demin S.A.Evseev M.I.Gostkin V.V.Kobets F.A.Rasu-lova S.V.Rozov E.T.Ruziev A.A.Solnyshkin T.N.Tran E.A.Yakushev B.S.Yuldashev Joint Institute for Nuclear Research(JINR) DubnaRussia Institute of Nuclear Physics of the Academy of Sciences of the Republic of Uzbekistan(INP ASRU) TashkentUzbekistan Institute of Physics of the Vietnam Academy of Science and Technology(IP VAST) HanoiVietnam

The yields of photonuclear reactions in the 107Ag,113In,and 115In nuclei were measured.Monte Carlo simulations were performed using the Geant4 code,and the results were compared with the experimental values.The isomeric ratios of the yields in the reactions 107Ag(γ,n)106m,gAg and 113In(γ,m)112m,gIn were determined,and the cross sections for the reactions 107Ag(γ,n)106gAg and 107Ag(γ,2n)105Ag at an energy of 20 MeV were calculated based on the experimental data.

关键词： 107Ag(γ,n)10mgAg and I13In(γ,n)12m-2In reactions cross section yield isomeric ratio simula-tion Geant4 TALYS

Distribution and origin of polycyclic aromatic hydrocarbons in surface sediments from an urban river basin at the Metropolitan Region of Curitiba,Brazil

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Journal of Environmental Sciences 2011年第6期23卷 904-911页

作者： Natalicio Ferreira Leite Patricio Peralta-Zamora Marco Tadeu Grassi Instituto de Tecnologia do Paran(TECPAR) 81350-010 CuritibaBrazil Departamento de Química Universidade Federal do Parana'(UFPR)C.P.1908181531-990 CuritibaBrazil

The concentrations of 16 polycyclic aromatic hydrocarbons（PAHs） were determined in surface sediment samples from nine sites located at the Iguau River Basin in the Metropolitan Region of Curitiba,Brazil to evaluate their distribution and sources.The total concentration of the PAHs was greater for sediments from highly urbanized areas,while the sediments from the Iraí Environmental Protection Area（Iraí EPA） showed significantly low concentrations.The sediments from the Iguau and Barigui rivers were classified as highly contaminated,while those from the Cercado and Curralinho rivers were classified as moderately contaminated.The predominance of PAHs containing two to four aromatic rings in most of the samples suggested the direct input of raw sewage into the water resources evaluated.Benzo[g,h,i]perylene,dibenzo[a,h]anthracene and indeno[1,2,3-cd]pyrene were predominant in sediments from the areas under the greatest urban and industrial development.The correlation between thermodynamic stability and the kinetics of evolution presented by the isomeric pairs indicated that combustion is the predominant source of PAHs in the sediments because the combustion of fossil fuels affected most of the points evaluated,followed by combustion of biomass and eventually combustion of oil product inputs.In general,the results showed that areas under strong urban influence,as well as the Iraí EPA,receive contributions of PAHs from similar sources.

关键词： PAHs trace level analysis fiver sediment isomeric ratio Igua^u River Basin

Direct neutron decay of analogue resonances in ^105Rh

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Chinese Physics B 2006年第1期15卷 104-107页

作者：胡碧涛 P.P.查鲁宾 U.U.尤拉夫列夫 Department of Modern Physics Lanzhou University Lanzhou 730000 China Faculty of Physics Saint Petersburg State University Saint Petersburg Russia

A new method, while takes into account the contribution of direct neutron decay of analogue resonances to the isomeric ratio resulting from （p,n） reaction, is used to analyse the published experimental data for the ... 详细信息

关键词： neutron decay reaction isobaric analogue state compound nuclei isomeric ratio