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Nuclear uncertainties in the s-process simulation

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Science China(Physics,Mechanics & Astronomy) 2013年第5期56卷 859-865页

作者： ZHANG YouJin CHEN YongShou GUO JianYou hou suqing LI ZhiHong SHI JianRong School of Physics and Material Science Anhui University China Institute of Atomic Energy Institute of Modern Physics Chinese Academy of Sciences National Astronomical Observatories Chinese Academy of Sciences

The heavy elements in the Universe are formed during the s- and r-processes mainly in AGB stars and supernovae, respectively. Simulation of s- and r-nucleosynthesis critically depends on the neutron capture and weak decay rates for all the nuclei on the reaction chain. The present work analyzes systematically the neutron capture rates (cross sections) for the s-process nuclei, including ～3000 rates on ～200 nuclei. The network calculations for the constant temperature s-process have been performed using the different data sets selected as the nuclear inputs to investigate the uncertainties in the predicted s-abundances. We show that the available cross sections of neutron capture on many s-process nuclei still carry large uncertainties, which lead to low accuracy in the determination of s-process isotope abundances. We analyze the neutron capture cross section data for the same unique isobar nucleus accorded by year from previous work. Such an analysis indicates that the s-process has been studied for more than fifty years and there exist two research stages around 1976 and 2002, respectively. The needs and opportunities for future experiments and theoretical tools are highlighted to remove the existing shortcomings in the neutron capture rates.

关键词： nucleosynthesis neutron capture reaction s-process nuclear reaction network

Reevaluation of the Astrophysical ^(7)Be(n,α)^(4)He Reaction Rate Relevant to BBN

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IMP & HIRFL Annual Report 2017年第1期 35-36页

作者： hou suqing 不详

Regarded as one of most challenging questions in cosmology and astrophysics,cosmological lithium problem refers to Big Bang model predict about three times ^(7)Li as much as we can *** the past two decades,it has motivated many scientists to explore the solution of eliminating this discrepancy between calculations and observations.

关键词： observations. eliminating lithium

From deep earth to deep stars: A different nuclear reaction path to generate calcium in ancient stars

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The Innovation 2023年第1期4卷 42-43页

作者： Hongliang Yan Jianrong Shi suqing hou CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesBeijing 100101China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Arecent study byZhanget al.1 reported a successful directmeasurementof the ^(19)F(p,g)^(20)Ne reaction down to the very low energy point of 186 *** measurement is extremely challenging on the surface of the Earth due to the presence of natural *** experimentwas donein the China Jinping Underground Laboratory(CJPL),which is currently the deepest underground laboratory.

关键词： earth stars underground

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彰显财富效应重树投资者信心

证券市场导报 2005年第3期 4-7页

作者：侯苏庆中国证监会河南监管局

近几年来,我国经济发展不断创出新水平,而作为反映国民经济“晴雨表”的证券市场却屡创新低,广大投资者不仅没能分享国民经济增长的成果,反而要承受巨大的投资损失。我国证券市场缺乏财富效应是造成这种局面的重要原因。采取有效措施彰... 详细信息

近几年来,我国经济发展不断创出新水平,而作为反映国民经济“晴雨表”的证券市场却屡创新低,广大投资者不仅没能分享国民经济增长的成果,反而要承受巨大的投资损失。我国证券市场缺乏财富效应是造成这种局面的重要原因。采取有效措施彰显积极的财富效应,可以重新恢复投资者的信心,为证券市场健康发展奠定坚实基础。

关键词：财富效应证券市场投资者信心经济发展投资损失国民经济增长中国彰显基础成果

A proposed direct measurement of cross section at Gamow window for key reaction 19F(p,α) 16O in Asymptotic Giant Branch stars with a planned accelerator in CJPL

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Science China(Physics,Mechanics & Astronomy) 2016年第5期59卷 76-82页

作者： JianJun He ShiWei Xu ShaoBo Ma Jun Hu LiYong Zhang ChangBo Fu NingTao Zhang Gang Lian Jun Su YunJu Li ShengQuan Yan YangPing Shen suqing hou BaoLu Jia Tao Zhang XiaoPeng Zhang Bing Guo Shigeru Kubono WeiPing Liu Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China University of Chinese Academy of Sciences Beijing 100049 China Department of Physics Shanghai Jiao Tong University Shanghai 200240 China China Institute of Atomic Energy P. O. Box 275(10) Beijing 102413 China RIKEN Nishina Center 2-1 Hirosawa Wako Saitama 351-0198 Japan

In 2014, the National Natural Science Foundation of China （NSFC） approved the Jinping Underground Nuclear Astrophysics laboratory （JUNA） project, which aims at direct cross-section measurements of four key stellar nuclear reactions right down to the Gamow windows. In order to solve the observed fluorine overabundances in Asymptotic Giant Branch （AGB） stars, measuring the key 19F（p,a）16O reaction at effective burning energies （i.e., at Gamow window） is established as one of the scientific research sub-projects. The present paper describes this sub-project in details, including motivation, status, experimental setup, yield and background estimation, aboveground test, as well as other relevant reactions.

关键词： Jinping Underground Nuclear Astrophysics laboratory (JUNA) direct measurement Gamow window cross section AGBstar nucleosynthesis

2 - 9 S-factor in 6Li（p,Y） 7Be Reaction at Low Energy

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IMP & HIRFL Annual Report 2013年第1期 45-46页

作者： Chen Size He Jianjun Xu Shiwei Zhang Liyong Hu Jun hou suqing Yu Xiangqing Ma Shaobo Claus Rolls Fakultait for Physik und Astronomie Ruhr-Universitat Bochum Bochum 44780 Germany.

Preparation of Laser Cladding Coating Undercooling Cu-based Alloy and Co on Non-equilibrium Solidification Structure

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 463-472页

作者：田徐铭 CAO Shichao hou Kai hou Xiaopeng WANG Hongfu 张煜 Department of Outpatient Xinzhou People’s HospitalXinzhou 034099China School of Mechanical Engineering North University of ChinaTaiyuan 030051China Department of Neurosurgery Xinzhou People’s HospitalXinzhou 034099China Department of Orthopedics Xinzhou People’s HospitalXinzhou 034099China

The effect of the gradient content of Co element on the solidification process of Cu-based alloy under deep under cooling conditions was *** non-equilibrium solidification structure of the under cooled alloy samples were *** is found that the rapidly solidified alloy has undergone twice grain refinement during the undercooling *** and significance of the maximum undercooling refinement structure of Cu60Ni35Co5 at T=253 K were ***-density defects were observed,such as dislocations,stacking faults networks,and twinning *** standard FCC diffraction pattern represents that it is still a single-phase *** on the metallographic diagram,EBSD and TEM data analysis,it is illustrated that the occurrence of grain refinement under high undercooling is due to stress induced *** addition,the laser cladding technology is used to coat Co-based alloy(Stellite12) coating on 304 stainless steel substrate;the microstructure of the coating cross-section was *** was found that the microstructure of the cross-section is presented as columnar crystals,planar crystals,and disordered growth direction,so that the coating has better hardness and wear *** electrochemical corrosion of the substrate and coating,it can be seen that the Co and Cr elements present in the coating are more likely to form a dense passivation film,which improved the corrosion resistance of the coating.

关键词： non-equilibrium solidification structure undercooling recrystallization laser cladding coating

Herbivore and native plant diversity synergistically resist alien plant invasion regardless of nutrient conditions

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Plant Diversity 2024年第5期46卷 640-647页

作者： Liping Shan Meng hou Key Laboratory of Wetland Ecology and Environment State Key Laboratory of Black Soils Conservation and UtilizationNortheast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China

Alien plant invasion success can be inhibited by two key biotic factors:native herbivores and plant ***,few studies have experimentally tested whether these factors interact to synergistically resist invasion success,especially factoring in changing global environments(*** enrichment).Here we tested how the synergy between native herbivores and plant diversity affects alien plant invasion success in various nutrient *** this purpose,we exposed alien plant species in potmesocosms to different levels of native plant diversity(4 vs.8 species),native generalist herbivores,and high and low soil nutrient *** found that generalist herbivores preferred alien plants to native plants,inhibiting invasion success in a native *** inhibition was amplified by highly diverse native ***,the amplified effect between herbivory and native plant diversity was independent of nutrient *** results suggest that a higher diversity of native communities can strengthen the resistance of native generalist herbivores to alien plant invasions by enhancing herbivory *** synergistic effect remains in force in nutrient-enriched habitats that are always invaded by alien plant *** results shed light on the effective control of plant invasions using multi-trophic means,even in the face of future global changes.

关键词： Biological invasion Biotic resistance Diversity conservation Plant-herbivore interactions Resource availability Global change

Integral Operators Between Fock Spaces

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 265-278页

作者： Yongqing LIU Shengzhao hou School of Mathematics and Statistics Changshu Institute of TechnologySuzhou 215006JiangsuChina School of Mathematical Sciences Soochow UniversitySuzhou 215006JiangsuChina

In this paper,the authors study the integral operator■induced by a kernel functionφ(z,·)∈F_α~∞between Fock *** 1≤p≤∞,they prove that S_φ:F_α^(1)→F_α^(p)is bounded if and only if■where k_(a)is the normali... 详细信息

关键词： Fock spaces Integral operators Normalized reproducing kernel