By bombarding the natural thorium targets with 14 MeVneutrons,^(229)Ra was produced through the reaction ^(232)Th(n,α)^(229)Ra.The radium activities were separated from the irradiated targets by coprecipitation with ...By bombarding the natural thorium targets with 14 MeVneutrons,^(229)Ra was produced through the reaction ^(232)Th(n,α)^(229)Ra.The radium activities were separated from the irradiated targets by coprecipitation with BaC_(12).A total of 18 weak γ rays with energies of 14.5,15.6,18.8,21.8,22.5,44.0,47.5,55.0,63.0,69.6,93.6,94.1,98.5,102.2,104.5,106.1,161.1,and 171.5keV,which could be assigned to the decay of ^(229)Ra,has been observed in the isolated radium fractions employing high-resolution HPGe detectors and γ(x)-γ coincidence methods.A decay scheme of ^(229)Ra based on these observations has been proposed.展开更多
A new transuranium neutron-deficient isotope ^(235)Am was produced via the reaction of ^(238)Pu(p,4n)^(235)Am by using a 35 MeV proton beam.The recoiled products were collected by a helium-jet and long-capillary syste...A new transuranium neutron-deficient isotope ^(235)Am was produced via the reaction of ^(238)Pu(p,4n)^(235)Am by using a 35 MeV proton beam.The recoiled products were collected by a helium-jet and long-capillary system.Americium isotopes were separated out by a rapid radiochemical method.X-ray,γ-ray,and x-γ coincidence measurements were taken in the study.According to ^(235)Pu decay γ-ray and Np K x-ray growth-decay property,^(235)Am was definitely identified and its half life is determined as 15±5 min.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.19375055the 8-5 Great Item in in Chinese Academy of Science under Grant No.KJ85-.
文摘By bombarding the natural thorium targets with 14 MeVneutrons,^(229)Ra was produced through the reaction ^(232)Th(n,α)^(229)Ra.The radium activities were separated from the irradiated targets by coprecipitation with BaC_(12).A total of 18 weak γ rays with energies of 14.5,15.6,18.8,21.8,22.5,44.0,47.5,55.0,63.0,69.6,93.6,94.1,98.5,102.2,104.5,106.1,161.1,and 171.5keV,which could be assigned to the decay of ^(229)Ra,has been observed in the isolated radium fractions employing high-resolution HPGe detectors and γ(x)-γ coincidence methods.A decay scheme of ^(229)Ra based on these observations has been proposed.
基金Supported by the National Natural Science Foundation of China under Grant No.19475052Chinese Academy of Sciences.
文摘A new transuranium neutron-deficient isotope ^(235)Am was produced via the reaction of ^(238)Pu(p,4n)^(235)Am by using a 35 MeV proton beam.The recoiled products were collected by a helium-jet and long-capillary system.Americium isotopes were separated out by a rapid radiochemical method.X-ray,γ-ray,and x-γ coincidence measurements were taken in the study.According to ^(235)Pu decay γ-ray and Np K x-ray growth-decay property,^(235)Am was definitely identified and its half life is determined as 15±5 min.
