Pre-neutron fragment mass yields in the vicinity of the thermal neutron energy are highly important for applications because of the larger fission cross sections of the^(235)U(n,f)and^(239)Pu(n,f)reactions.In this pap...Pre-neutron fragment mass yields in the vicinity of the thermal neutron energy are highly important for applications because of the larger fission cross sections of the^(235)U(n,f)and^(239)Pu(n,f)reactions.In this paper,preneutron fragment mass yields at incident energies from thermal up to 20 MeV are systematically studied using an empirical fission potential(EFP)model,the potential parameters of which are obtained from the measured data.The energy dependences of the peaks and valleys of the pre-neutron fragment mass yields are described by exponential and linear functions for the^(235)U(n,f)and^(239)Pu(n,f)reactions,respectively.The energy dependences of the evaporation neutrons,which play a crucial role in the reasonable description of pre-neutron fragment mass yields,are also obtained from the fission cross sections.The pre-neutron fragment mass yields in this study are not only consistent with the results of previous studies in regions of several Me Vs but also agree well with existing measured data at incident energies from thermal up to 20 MeV.The results show that the feasibility of this EFP model is verified in this extended energy region.展开更多
The creation and relaxation of double K-hole states 1s^(0)2s^(2)2p^(6)np(n≥3)of Ne^(1+)in the interaction with ultraintense ultrafast x-ray pulses are theoretically investigated.The x-ray photon energies are selected...The creation and relaxation of double K-hole states 1s^(0)2s^(2)2p^(6)np(n≥3)of Ne^(1+)in the interaction with ultraintense ultrafast x-ray pulses are theoretically investigated.The x-ray photon energies are selected so that x-rays first photoionize1s^(22)s^(22)p^(6) of a neon atom to create a single K-hole state of 1s2s^(22)p^(6) of Ne^(1+),which is further excited resonantly to double K-hole states of ls^(0)2s^(2)2p^(6)np(n≥3).A time-dependent rate equation is used to investigate the creation and relaxation processes of 1s^(0)2s^(2)2p^(6)np,where the primary microscopic atomic processes including photoexcitation,spontaneous radiation,photoionization and Auger decay are considered.The calculated Auger electron energy spectra are compared with recent experimental results,which shows good agreement.The relative intensity of Auger electrons is very sensitive to the photon energy and bandwidth of x-ray pulses,which could be used as a diagnostic tool for x-ray free electron laser and atom experiments.展开更多
目的通过对双硫仑相关文献进行计量、共现、共被引及可视化分析,以探索该领域的研究进展及动态前沿。方法以主题词"Disulfiram"在Web of Science数据库中进行文献检索。运用CiteSpace对获得的文献进行国家、机构、关键词、文...目的通过对双硫仑相关文献进行计量、共现、共被引及可视化分析,以探索该领域的研究进展及动态前沿。方法以主题词"Disulfiram"在Web of Science数据库中进行文献检索。运用CiteSpace对获得的文献进行国家、机构、关键词、文献和期刊的分析。结果自2002年以来,有关双硫仑研究热度呈持续上升趋势。可视化分析结果显示,高产国家/机构是来自美国、中国的高等院校,美国在研究双硫仑领域占据主要力量,沈阳药科大学作为国内研究较早且唯一一所进入全球发文量前十的研究机构,其文章具有较强的说服力;共被引频次最多的期刊为"ALCOHOL CLIN EXP RES",其收录的文章具有较高的借鉴价值;热点关键词有"Disulfiram","Inhibition","Naltrexone","Double blind"等,显示近年来双硫仑研究方向主要集中在抗癌领域。结论作为老药,双硫仑仍是国内外持续关注的热点话题,且在抗癌领域的"新用"极具临床开发价值。展开更多
基金Supported by the National Natural Science Foundation of China(12065003)the Natural Science Foundation of Guangxi(2019GXNSFDA185011)+2 种基金the Key Laboratory of Neutron Physics China Academy of Engineering Physics(2018BA03)the Scientific Research and Technology Development Project of Guilin(20210104-2)the Central Government Guides Local Scientic and Technological Development Funds of China(Guike ZY22096024)。
文摘Pre-neutron fragment mass yields in the vicinity of the thermal neutron energy are highly important for applications because of the larger fission cross sections of the^(235)U(n,f)and^(239)Pu(n,f)reactions.In this paper,preneutron fragment mass yields at incident energies from thermal up to 20 MeV are systematically studied using an empirical fission potential(EFP)model,the potential parameters of which are obtained from the measured data.The energy dependences of the peaks and valleys of the pre-neutron fragment mass yields are described by exponential and linear functions for the^(235)U(n,f)and^(239)Pu(n,f)reactions,respectively.The energy dependences of the evaporation neutrons,which play a crucial role in the reasonable description of pre-neutron fragment mass yields,are also obtained from the fission cross sections.The pre-neutron fragment mass yields in this study are not only consistent with the results of previous studies in regions of several Me Vs but also agree well with existing measured data at incident energies from thermal up to 20 MeV.The results show that the feasibility of this EFP model is verified in this extended energy region.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12074430 and 11974423)。
文摘The creation and relaxation of double K-hole states 1s^(0)2s^(2)2p^(6)np(n≥3)of Ne^(1+)in the interaction with ultraintense ultrafast x-ray pulses are theoretically investigated.The x-ray photon energies are selected so that x-rays first photoionize1s^(22)s^(22)p^(6) of a neon atom to create a single K-hole state of 1s2s^(22)p^(6) of Ne^(1+),which is further excited resonantly to double K-hole states of ls^(0)2s^(2)2p^(6)np(n≥3).A time-dependent rate equation is used to investigate the creation and relaxation processes of 1s^(0)2s^(2)2p^(6)np,where the primary microscopic atomic processes including photoexcitation,spontaneous radiation,photoionization and Auger decay are considered.The calculated Auger electron energy spectra are compared with recent experimental results,which shows good agreement.The relative intensity of Auger electrons is very sensitive to the photon energy and bandwidth of x-ray pulses,which could be used as a diagnostic tool for x-ray free electron laser and atom experiments.
文摘系统评价真武汤加减方治疗充血性心力衰竭的临床疗效。计算机检索the Cochrane Library,Pub Med,EMbase 3个外文数据库和中国生物医学文献数据库(CBM)、中国期刊全文数据库(CNKI)、中国科技期刊全文数据库(VIP)和万方数据库(Wanfang database)4个中文数据库,检索年限为建库至2016年7月,检索所有真武汤治疗充血性心力衰竭的随机对照文献(randomized control trials,RCTs),并追索纳入研究的参考文献。由2名评价员分别对检索出的文献进行筛选并提取有效数据,采用Rev Man 5.3软件对数据进行Meta分析。该研究共纳入13个临床随机对照试验,共计982例患者。Meta分析结果显示,与单纯应用西药相比,在西药基础上应用真武汤加减方可改善患者心功能总有效率:[RR=1.16,95%CI(1.10,1.22)],增加射血分数[MD=7.12,95%CI=(3.98,10.27)],增加心搏指数[MD=6.92,95%CI(5.21,8.62)],增加每搏输出量[MD=11.18,95%CI(6.04,16.33)],提高心脏指数[MD=0.50,95%CI(-0.29,1.30)]。真武汤加减方结合常规治疗能改善充血性心力衰竭的临床症状,但系统评价纳入的所有研究方法学和报告质量均较低,样本量少,因真武汤加减治疗充血性心力衰竭的临床疗效仍需要严格、多中心、大样本的随机双盲对照试验加以验证。
