We have performed first-principles density functional theory calculations to investigate the retention and migration of hydrogen in Be_(22) W, a stable low-W intermetallic compound. The solution energy of interstiti...We have performed first-principles density functional theory calculations to investigate the retention and migration of hydrogen in Be_(22) W, a stable low-W intermetallic compound. The solution energy of interstitial H in Be_(22) W is found to be 0.49 eV lower, while the diffusion barrier, on the other hand, is higher by 0.13 eV compared to those in pure hcp-Be. The higher solubility and lower diffusivity for H atoms make Be_(22) W a potential beneficial secondary phase in hcp-Be to impede the accumulation of H atoms, and hence better resist H blistering. We also find that in Be_(22) W, the attraction between an interstitial H and a beryllium vacancy ranges from 0.34 eV to 1.08 eV, which indicates a weaker trapping for hydrogen than in pure Be. Our calculated results suggest that small size Be_(22) W particles in hcp-Be might serve as the hydrogen trapping centers, hinder hydrogen bubble growth, and improve the resistance to irradiation void swelling, just as dispersed oxide particles in steel do.展开更多
We present a qubit-loss-free(QLF)fusion scheme for generating large-scale atom W states in cavity quantum electrodynamics(QED)system.Compared to the most current fusion schemes which are conditioned on the case where ...We present a qubit-loss-free(QLF)fusion scheme for generating large-scale atom W states in cavity quantum electrodynamics(QED)system.Compared to the most current fusion schemes which are conditioned on the case where one particle can be extracted from each initial W state to the fusion process,our scheme will access one or two particles from each W state.Based on the atom–cavity-field detuned interaction,three jWin+m+t states can be generated from the jWin,jWim,and jWit states with the help of two auxiliary atoms,and three jWin+m+t+q states can be generated from jWin,jWim,jWit,and a jWiq state with the help of three auxiliary atoms.Comparing the numerical simulations of the resource cost of fusing three small-size W states based on the previous schemes,our fusion scheme seems to be more efficient.This QLF fusion scheme can be generalized to the case of fusing k different or identical particle W states.Furthermore,with no qubit loss,it greatly reduces the number of fusion steps and prepares W states with larger particle numbers.展开更多
为了探讨医疗学术会议的健康传播效能,本研究以2022中国肿瘤学大会(Chinese Congress on Oncology, CCO)为例,以哈罗德·拉斯韦尔5W传播模式为分析框架,对新浪微博平台相关话题下的所有微博进行内容分析和社会语义网络分析。结果显...为了探讨医疗学术会议的健康传播效能,本研究以2022中国肿瘤学大会(Chinese Congress on Oncology, CCO)为例,以哈罗德·拉斯韦尔5W传播模式为分析框架,对新浪微博平台相关话题下的所有微博进行内容分析和社会语义网络分析。结果显示,传播以会议资讯、学术交流和科普宣教3类信息为抓手,以医学专业人士和有健康需求的一般受众为传播目标,通过调动政务微博、主流媒体和医疗健康领域意见领袖的媒介组合,实现了3.5亿人次的微博传播阅读量。本研究认为,可以通过议程设置掌握舆论引导主动权,针对不同受众选择合适的传播组合方式,找准宣传契合点向新闻媒体最大化借力借势,充分重视社群作用激发大众传播潜能,为提升医疗学术会议健康传播效能提供理论指导和实践经验。展开更多
基金Project supported by the National Magnetic Confinement Fusion Program of China(Grant Nos.2014GB104003 and 2015GB105001)the National Natural Science Foundation of China(Grant No.51504033)
文摘We have performed first-principles density functional theory calculations to investigate the retention and migration of hydrogen in Be_(22) W, a stable low-W intermetallic compound. The solution energy of interstitial H in Be_(22) W is found to be 0.49 eV lower, while the diffusion barrier, on the other hand, is higher by 0.13 eV compared to those in pure hcp-Be. The higher solubility and lower diffusivity for H atoms make Be_(22) W a potential beneficial secondary phase in hcp-Be to impede the accumulation of H atoms, and hence better resist H blistering. We also find that in Be_(22) W, the attraction between an interstitial H and a beryllium vacancy ranges from 0.34 eV to 1.08 eV, which indicates a weaker trapping for hydrogen than in pure Be. Our calculated results suggest that small size Be_(22) W particles in hcp-Be might serve as the hydrogen trapping centers, hinder hydrogen bubble growth, and improve the resistance to irradiation void swelling, just as dispersed oxide particles in steel do.
基金the National Natural Science Foun-dation of China(Grant No.12204311)the Jiangxi Natural Science Foundation(Grant No.20224BAB211025).
文摘We present a qubit-loss-free(QLF)fusion scheme for generating large-scale atom W states in cavity quantum electrodynamics(QED)system.Compared to the most current fusion schemes which are conditioned on the case where one particle can be extracted from each initial W state to the fusion process,our scheme will access one or two particles from each W state.Based on the atom–cavity-field detuned interaction,three jWin+m+t states can be generated from the jWin,jWim,and jWit states with the help of two auxiliary atoms,and three jWin+m+t+q states can be generated from jWin,jWim,jWit,and a jWiq state with the help of three auxiliary atoms.Comparing the numerical simulations of the resource cost of fusing three small-size W states based on the previous schemes,our fusion scheme seems to be more efficient.This QLF fusion scheme can be generalized to the case of fusing k different or identical particle W states.Furthermore,with no qubit loss,it greatly reduces the number of fusion steps and prepares W states with larger particle numbers.
文摘为了探讨医疗学术会议的健康传播效能,本研究以2022中国肿瘤学大会(Chinese Congress on Oncology, CCO)为例,以哈罗德·拉斯韦尔5W传播模式为分析框架,对新浪微博平台相关话题下的所有微博进行内容分析和社会语义网络分析。结果显示,传播以会议资讯、学术交流和科普宣教3类信息为抓手,以医学专业人士和有健康需求的一般受众为传播目标,通过调动政务微博、主流媒体和医疗健康领域意见领袖的媒介组合,实现了3.5亿人次的微博传播阅读量。本研究认为,可以通过议程设置掌握舆论引导主动权,针对不同受众选择合适的传播组合方式,找准宣传契合点向新闻媒体最大化借力借势,充分重视社群作用激发大众传播潜能,为提升医疗学术会议健康传播效能提供理论指导和实践经验。