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Direct measurement of the break-out ^(19)F(p,γ)^(20)Ne reaction in the China Jinping underground laboratory(CJPL)

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Nuclear Science and Techniques 2024年第8期35卷 142-152页

作者： Yin‑Ji Chen Hao Zhang Li‑Yong Zhang Jian‑Jun He Richard James deBoer Michael Wiescher Alexander Heger David Kahl Jun Su Daniel Odell Xin‑Yue Li Jian‑Guo Wang long Zhang Fu‑Qiang Cao Zhi‑Cheng Zhang Xin‑Zhi Jiang Luo‑Huan Wang Zi‑Ming Li Lu‑Yang song Liang‑Ting Sun Qi Wu Jia‑Qing Li Bao‑Qun Cui Li‑Hua Chen Rui‑Gang Ma Er‑Tao Li Gang Lian Yao‑De sheng Zhi‑Hong Li Bing Guo Wei‑Ping Liu Key Laboratory of Beam Technology of the Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Department of Physics and Astronomy The Joint Institute for Nuclear AstrophysicsUniversity of Notre DameNotre DameIN 46556USA School of Physics and Astronomy Monash UniversityClaytonVIC 3800Australia Facility for Rare Isotope Beams Michigan State UniversityEast LansingMI 48824USA Institute of Nuclear and Particle Physics and Department of Physics and Astronomy Ohio UniversityAthensOH 45701USA Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China China Institute of Atomic Energy Beijing 102413China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China College of Science Southern University of Science and TechnologyShenzhen 518055China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China Key Laboratory of Nuclear Physics and Ion‑Beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China School of Mathematics and Physics Handan UniversityHandan 056005China

Calcium production and the stellar evolution of first-generation stars remain fascinating mysteries in *** one possible nucleosynthesis scenario,break-out from the hot carbon–nitrogen–oxygen(HCNO)cycle was thought to be the source of the calcium observed in these oldest ***,according to the stellar modeling,a nearly tenfold increase in the thermonuclear rate ratio of the break-out ^(19)F(p,γ)^(20) Ne reaction with respect to the competing ^(19)F(p,α)^(16) O back-processing reaction is required to reproduce the observed calcium *** performed a direct measurement of this break-out reaction at the China Jinping underground *** measurement was performed down to the low-energy limit of E_(c.m.)=186 keV in the center-of-mass *** key resonance was observed at 225.2 keV for the first *** a temperature of approximately 0.1 GK,this new resonance enhanced the thermonuclear ^(19)F(p,γ)^(20) Ne rate by up to a factor of≈7.4,compared with the previously recommended NACRE *** is of particular interest to the study of the evolution of the first stars and implies a stronger breakdown in their“warm”CNO cycle through the ^(19)F(p,γ)^(20) Ne reaction than previously *** break-out resulted in the production of the calcium observed in the oldest stars,enhancing our understanding of the evolution of the first stars.

关键词： Nuclear astrophysics First stars Abundance of calcium Reaction cross section Reaction rate China Jinping underground laboratory(CJPL) JUNA

基于sDTW-最近邻算法的知情交易概率研究

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数学的实践与认识 2018年第10期48卷 76-82页

作者：钱龙黄嵩武晨北京大学软件与微电子学院北京100871 中国科学院数学与系统科学研究院北京100190 中国科学院大学北京100049

采用高频股指期货交易数据以构建新型知情交易概率DPIN，随后根据DPIN取值的不同，使用了基于sDTW的最近邻算法尝试对沪深300股指期货市场的不同知情交易状况进行分类和预测．通过调整参数和使用不同的形状描述符来进行优化，所使用的... 详细信息

采用高频股指期货交易数据以构建新型知情交易概率DPIN，随后根据DPIN取值的不同，使用了基于sDTW的最近邻算法尝试对沪深300股指期货市场的不同知情交易状况进行分类和预测．通过调整参数和使用不同的形状描述符来进行优化，所使用的算法能够以较高的准确度对DPIN进行分类预测，这将有助于理解我国股指期货市场的内在信息机制．

关键词：知情交易概率动态时间规整高频交易最近邻算法

我国质量提升率测算及其对经济增长的贡献率研究

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中国管理科学 2021年第12期29卷 203-214页

作者：周涵婷宋明顺程龙生郑素丽蒋晶南京理工大学经济管理学院江苏南京210094 中国计量大学经济与管理学院浙江杭州310018

基于经济增长理论,提取质量要素构建"技术进步-资本增长-质量提升"的多指标多原因结构方程模型,并利用蒙特卡洛-贝叶斯插补法测算1998-2017年的质量提升率及其对经济增长的贡献率。研究发现:第一,创新会拉动质量提升,质量提升会提高产... 详细信息

基于经济增长理论,提取质量要素构建"技术进步-资本增长-质量提升"的多指标多原因结构方程模型,并利用蒙特卡洛-贝叶斯插补法测算1998-2017年的质量提升率及其对经济增长的贡献率。研究发现:第一,创新会拉动质量提升,质量提升会提高产品异质性进而形成高质量贸易关系,显著促进对外贸易额增长。但会增加能源消耗,亟待转变能源结构;第二,质量提升率均值5.11%,呈现阶梯式上升态势,良好的国际贸易环境有利于要素流通、要素质量提升,从而获取更高水平的要素收入。国家宏观调控措施在保障要素供给质量、提高配置效率和均衡供需结构方面发挥重要作用;第三,质量提升率对经济增长的贡献率最大值16.82%、均值8.84%,低于技术进步和资本增长的贡献率,但趋势上存在交互影响和互补作用,质量提升已经成为高质量发展的重要显性表达。

关键词：结构方程模型贝叶斯估计贝叶斯插补法质量提升率经济增长贡献率

具有特殊压力含有源项一维可压Euler方程组的弱解存在性

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中山大学学报（自然科学版） 2011年第6期50卷 23-29页

作者：宋国强肖箭盛立人安徽医科大学卫生管理学院安徽合肥230032 南京航空航天大学航空宇航学院江苏南京210016 安徽大学数学科学学院安徽合肥230039

研究一类双曲系统——具有特殊压力含有源项的一维可压Euler方程组的Cauchy问题,应用补偿紧性理论和最大值原理,得到其有界弱解的整体存在性结果。所研究系统的齐次形式是1858年Earnshaw在研究等熵流体时第一次被推导出来,同时也被称为... 详细信息

研究一类双曲系统——具有特殊压力含有源项的一维可压Euler方程组的Cauchy问题,应用补偿紧性理论和最大值原理,得到其有界弱解的整体存在性结果。所研究系统的齐次形式是1858年Earnshaw在研究等熵流体时第一次被推导出来,同时也被称为一位可压流的Euler方程组。其中的关键是用最大值原理得到相应的抛物方程组解的L∞估计,同时举出满足定理1条件(C1)–(C3)的一些具体源项。

关键词：补偿紧性理论最大值原理弱解熵-熵流对 Dirac测度

SrAl_2O_4:Eu^(2+),Dy^(3+)长余辉发光材料的喷雾热解制备及其表征

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发光学报 2011年第8期32卷 766-772页

作者：王林生李敏赖华生文小强周健黄可龙中南大学化学化工学院湖南长沙410083 赣州有色冶金研究所江西赣州341000 江西理工大学材料与化学工程学院江西赣州341000

采用喷雾热解两段法制备了SrAl2O4∶Eu2+,Dy3+长余辉发光材料,并利用XRD、SEM、荧光长余辉亮度测试等方法分析了不同制备工艺条件下SrAl2O4∶Eu2+,Dy3+发光材料的结构、形貌以及发光性能的变化。结果表明:采用喷雾热解两段法可制备出球... 详细信息

采用喷雾热解两段法制备了SrAl2O4∶Eu2+,Dy3+长余辉发光材料,并利用XRD、SEM、荧光长余辉亮度测试等方法分析了不同制备工艺条件下SrAl2O4∶Eu2+,Dy3+发光材料的结构、形貌以及发光性能的变化。结果表明:采用喷雾热解两段法可制备出球形SrAl2O4∶Eu2+,Dy3+长余辉发光材料,SrAl2O4∶Eu2+,Dy3+的晶体结构与α-SrAl2O4磷石英晶体结构相同。热解温度、还原温度、添加剂对产物的形貌、粒度分布、发光性能有较大影响。较之高温固相法,喷雾热解法制备的SrAl2O4∶Eu2+,Dy3+具有发光性能好、形貌好、粒度分布窄等优点。

关键词：喷雾热解法 SrAl2O4∶Eu2+,Dy3+ 长余辉发光材料

Transient ST-segment elevation after transseptal puncture for atrial fibrillation ablation in two cases

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Chinese Medical Journal 2012年第5期125卷 941-944页

作者： CHENG Yan-li DONG Jian-zeng LIU Xing-peng long De-yong FANG Dong-ping YU Rong-hui TANG Ri-bo MA Chang-sheng Department of Cardiology Beijing An Zhen HospitalCapital Medical UniversityBeijing100029China

The present report demonstrates two cases of transient inferior ST-segment elevation accompanied by profound hypotension and bradycardia immediately after transseptal puncture for catheter ablation of atrial fibrillation. This rare complication of transseptal puncture was resolved quickly within several minutes. The most likely mechanism of this phenomenon is coronary vasospasm, although coronary embolism can not be ruled out completely. This complication is characterized as follows：（1） The right coronary artery might be the most likely involved vessel and therefore myocardial ischemia usually occurs in the inferior wall of left ventricular; （2） Reflex hypotension and bradycardia by the Bezold-Jarisch reflex secondary to inferior ischemia often occur at the same time. Though it appears to be a transient and completely reversible phenomenon, there are still potential life-threatening risks because of myocardial ischemia and profound haemodynamic instability. Clinical cardioloaists should be aware of this rare comolication and orooerlv deal with it.

关键词： ST-segment elevation transseptal puncture atrial fibrillation catheter ablation

The galaxy luminosity function in the LAMOST Complete Spectroscopic Survey of Pointing Area at the Southern Galactic Cap

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Research in Astronomy and Astrophysics 2019年第8期19卷 69-80页

作者： Pin-song Zhao Hong Wu Cong Kevin Xu Ming Yang Fan Yang Yi-Nan Zhu Man I Lam Jun-Jie Jin Hai-long Yuan Hao-Tong Zhang Shi-Yin Shen Jian-Rong Shi A-Li Luo Xue-Bing Wu Yong-Heng Zhao Yi-Peng Jing Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing100049China Chinese Academy of Sciences South America Center for Astronomy China-Chile Joint Center for AstronomyCamino El Observatorio1515Las CondesSantiagoChile IAASARS National Observatory of AthensVas.Pavlou&I.MetaxaPenteli15236Greece Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy ofSciencesShanghai200030China Department of Astronomy School of PhysicsPeking UniversityBeijing100871China School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai200240China

We present optical luminosity functions(LFs) of galaxies in the0.1 g,0.1 r,0.1 i bands, calculated using data in40 deg2 sky area of the LAMOST Complete Spectroscopic Survey of Pointing Area(LaCoSSPAr) in the Southern Galactic Cap. Redshifts for galaxies brighter than r = 18.1 were obtained mainly with LAMOST. In each band, LFs derived using both parametric and non-parametric maximum likelihood methods agree well with each other. In the0.1 r band, our fitting parameters of the Schechter function are φ*=(1.65 ± 0.36) × 10-2 h3 Mpc-3, M*=-20.69 ± 0.06 mag and α =-1.12 ± 0.08,which agree with previous studies. Separate LFs are also derived for emission line galaxies and absorption line galaxies. The LFs of absorption line galaxies show a dip at0.1 r 18.5 and can be fitted well by a double-Gaussian function, suggesting a bimodality in passive galaxies.

关键词： galaxies:luminosity function,mass function galaxies:statistics galaxies:distances and redshifts

Simulation of plasma properties in magnetron sputtering for two kinds of cathode targets

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Radiation Detection Technology and Methods 2020年第1期4卷 10-16页

作者： Di-zhou Guo Shuang-kai Chen Yong-sheng Ma Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Introduction During magnetron sputtering process,the common structure of cathode target is planar target and cylindrical rotating *** this study,cylindrical rotating target is used and two kinds of cathode targets were investigated by COMSOL Multiphysics software(The official network of COMSOL Multiphysics ***://***/).We will elucidate the difference between the two types of cathode target and determine the type of cathode target used in the final *** system configuration We explore the plasma distribution in the radio frequency cavity,so the simulation process was divided into two steps:building RF cavity model and setting up plasma discharge *** main part of the model included the radio frequency cavity substrate(divided into two tube parts and middle ellipsoid part),the cathode and the *** the plasma discharge parameters are as follows:Ar gas was used with 1.5 Pa;magnetic field strength of iron core was set to 1000 Gs;the applied voltage of cathode was set to-160 V;and anode was set to 0 *** For the long cathode target and the short cathode target,the main difference is the electric field *** the electric field lines are denser for the long cathode target,the electric field intensity is stronger,and then the initial energy obtained by electrons is *** the plasma discharge process,because of the high electron energy,the plasma density produced is more than the simulation of the short cathode *** under the same simulation time,the residual energy of electrons is more for the long cathode target,which is the reason for the higher electron *** the previous experimental experience,we know that the film quality formed by higher electron energy is *** simulation in this work shows that the electron energy corresponding to the long cathode target is higher than that of the short cathode target,so we choose the long cathode target as the experimental targ

关键词： Magnetron sputter COMSOL Multiphysics Plasma properties Plasma simulation Cathode targets

基于软件OpenSim的人体运动建模理论及其应用领域概述

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医用生物力学 2015年第4期30卷 373-379页

作者：宋和胜钱竞光唐潇上海体育学院运动科学学院上海200438 贵州师范大学体育学院贵阳550001 南京体育学院科研处南京210014

红外捕捉系统、高速摄像、平面摄影、表面肌电测试等现行实验室测试手段不能显示人体运动时肌肉产生肌力的具体信息以及准确阐释神经-肌肉协调机制。因此,计算机模拟与仿真应运而生。目前,国内用来进行人体动作仿真的软件主要有Life MOD... 详细信息

红外捕捉系统、高速摄像、平面摄影、表面肌电测试等现行实验室测试手段不能显示人体运动时肌肉产生肌力的具体信息以及准确阐释神经-肌肉协调机制。因此,计算机模拟与仿真应运而生。目前,国内用来进行人体动作仿真的软件主要有Life MOD、Any Body、ANSYS等,这些软件有其自身的缺陷,如肌肉控制不够精确、价钱昂贵等。为了更好解决肌肉模拟问题,斯坦福大学团队研发了一款免费软件Open Sim,它是基于C++和JAVA语言开发的一款应用于肌肉模型开发、模拟仿真与分析神经肌肉系统的开放性软件。以计算机建模与数学理论推导为基础,对Open Sim建模理论和步骤进行详细介绍,为国内从事运动生物力学研究学者提供一些理论参考;同时,探讨未来利用Open Sim建模仿真研究的主要方向,例如通过Open Sim的模拟研究可以探求偏瘫步态、帕金森步态等异常步态的神经-肌肉机制,为异常步态康复手段的改进和完善提供依据。

关键词： OpenSim软件计算机仿真肌肉模型运动生物力学