A new statistical method for systematizing the nuclei fission fragments, investigation of their mass and charge spectra and neutron fission parameters has been suggested. In proposed method, the mass and charge yields...A new statistical method for systematizing the nuclei fission fragments, investigation of their mass and charge spectra and neutron fission parameters has been suggested. In proposed method, the mass and charge yields of nucleons are determined from the equilibrium conditions of the nuclear fragments post-fission ensemble. Here we consider protons and neutrons of different fragments as statistically non-equivalent. The abilities of the proposed statistical method for explanation of the U, Pa, Th, Ac and Ra post-fission fragments ordering and neutron emission function calculation have been demonstrated.展开更多
The concentration of the natural ultra-trace radionuclides CI and U in the uranium depended on the neutron flux.In this article,a method for measuring 36C1 and 236U in the same uranium mineral with accelerator mass sp...The concentration of the natural ultra-trace radionuclides CI and U in the uranium depended on the neutron flux.In this article,a method for measuring 36C1 and 236U in the same uranium mineral with accelerator mass spectrometry was developed in China Institute of Atomic Energy,providing a protocol of the potential application of 236U in uranium mining,environmental,and geological research.The two samples were from Guangxi and Shanxi province,China,and their ratios 36Cl/C1 and 236U/238U were measured.More experimental data conduced to understand the natural nuclides in the uranium mineral.We plan to conduct more efforts on the research.展开更多
In this paper, we develop a new path search algorithm which considers all the degrees of freedom and apply it on our calculated five-dimensional potential energy surface(PES) of^(236) U. Asymmetric and symmetric fissi...In this paper, we develop a new path search algorithm which considers all the degrees of freedom and apply it on our calculated five-dimensional potential energy surface(PES) of^(236) U. Asymmetric and symmetric fission paths and barriers are obtained.展开更多
The rare isotope ^236U has a half-life of 2.342（3）×107 years, and is produced principally by thermal neutron capture on ^235U. The isotopic atom ratio of ^236U/^238U depends on the integral thermal neutron flux...The rare isotope ^236U has a half-life of 2.342（3）×107 years, and is produced principally by thermal neutron capture on ^235U. The isotopic atom ratio of ^236U/^238U depends on the integral thermal neutron flux received by the material of interest. ^236U is potentially useful as a ＂fingerprint＂ for indicating the presence of neutron-irradiated uranium usually originating from nuclear activity. By extracting negative molecular ion UO^- from the uranium oxide target, simulating the ^236U^16O^- beam transport with ^238U^16O^- and ^208Pb2^16O^- pilot molecular ion beam, transporting the ^236U-containing ion beam with a high resolution injection magnet analyzer and electrostatic analyzer system, and finally identifying and detecting ^236U with a time-of-flight detector （TOF）, a method for AMS （Accelerator Mass Spectrometry） measurement of ^236U was established on the HI-13 Accelerator AMS system at China Institute of Atomic Energy.展开更多
文摘A new statistical method for systematizing the nuclei fission fragments, investigation of their mass and charge spectra and neutron fission parameters has been suggested. In proposed method, the mass and charge yields of nucleons are determined from the equilibrium conditions of the nuclear fragments post-fission ensemble. Here we consider protons and neutrons of different fragments as statistically non-equivalent. The abilities of the proposed statistical method for explanation of the U, Pa, Th, Ac and Ra post-fission fragments ordering and neutron emission function calculation have been demonstrated.
基金Supported by National Natural Science Foundation of China(No.41166002)Guangxi Natural Science Foundation(No.2012GXNSFBA053004)+1 种基金Scientific Research Foundation of Guangxi Higher Education(No.201102ZD001)Scientific Research Foundation ofGuangxi University(No.XBZ100773)
文摘The concentration of the natural ultra-trace radionuclides CI and U in the uranium depended on the neutron flux.In this article,a method for measuring 36C1 and 236U in the same uranium mineral with accelerator mass spectrometry was developed in China Institute of Atomic Energy,providing a protocol of the potential application of 236U in uranium mining,environmental,and geological research.The two samples were from Guangxi and Shanxi province,China,and their ratios 36Cl/C1 and 236U/238U were measured.More experimental data conduced to understand the natural nuclides in the uranium mineral.We plan to conduct more efforts on the research.
基金Supported by the Major Research plan of National Natural Science of China under Grant No.11790324the National Key Research and Development Program of China under Grant Nos.2016YY0200804 and 2017YFF0206205+1 种基金the National Magnetic Confinement Fusion Science Program of China under Grant Nos.2013GB106004 and 2012GB-101003the National Natural Science Foundation of China under No.1179320013
文摘In this paper, we develop a new path search algorithm which considers all the degrees of freedom and apply it on our calculated five-dimensional potential energy surface(PES) of^(236) U. Asymmetric and symmetric fission paths and barriers are obtained.
基金Supported by NSAF (National Nature Science Fundation-China Academy of Engineering Physics Fundation) (10576040)
文摘The rare isotope ^236U has a half-life of 2.342（3）×107 years, and is produced principally by thermal neutron capture on ^235U. The isotopic atom ratio of ^236U/^238U depends on the integral thermal neutron flux received by the material of interest. ^236U is potentially useful as a ＂fingerprint＂ for indicating the presence of neutron-irradiated uranium usually originating from nuclear activity. By extracting negative molecular ion UO^- from the uranium oxide target, simulating the ^236U^16O^- beam transport with ^238U^16O^- and ^208Pb2^16O^- pilot molecular ion beam, transporting the ^236U-containing ion beam with a high resolution injection magnet analyzer and electrostatic analyzer system, and finally identifying and detecting ^236U with a time-of-flight detector （TOF）, a method for AMS （Accelerator Mass Spectrometry） measurement of ^236U was established on the HI-13 Accelerator AMS system at China Institute of Atomic Energy.
