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The evolution and morphological stability of a spherical crystal

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science china(Technological {2.) 2008年第3期51卷 225-243页

作者： chen mingwen1,2. wang {2. xu jianjun3,4.1 school of applied sciences, University of science and technology beijing, beijing 100083. china 2.school of Materials science and Engineering, University of science and technology beijing, beijing 100083. china 3 school of Mathematical sciences, Nankai University, Tianjin 300071, china 4 Department of Mathematics and Statistics, McGill University, Montreal H3A 2.6, Canada school of applied {2. University of Science and Technology Beijing Beijing China school of Materials science and Engineering University of Science and Technology Beijing Beijing China school of Mathematical sciences Nankai University Tianjin China Department of Mathematics and Statistics McGill University Montreal Canada

The growth model of a spherical crystal in the undercooled melt including the surface energy, interfacial kinetics and convective flow is established. The effect of the convective flow induced by a small far field flow on the evolution and morphological stability of the interface of the spherical crystal is studied. The interface shape of the spherical crystal, which is affected by the far field flow, and the dispersion relation of the growth rate of amplitude of the perturbed interface are derived. It is shown that the convection induced by the far field flow makes the interface of the growing spherical crystal further grow in the upstream direction of the far field flow and inhibit growth in the downstream direction; the interface of the decaying spherical crystal further decays in the upstream direction and inhibits decay in the downstream direction. The theoretical result suggests that both the growth of the sphere in the upstream direction and the decay of the sphere in the downstream direction make the spherical crystal tend to evolve into an oval; the morphological stability of the interface depends on a certain radius R c such that the spherical crystal is unstable when its radius is greater than R c and stable when its radius is less than R c . The surface energy and interfacial kinetics have strong stabilizing effects on the growth of the spherical crystal. In the meantime interfacial kinetics is a table factor of the interface when the interface of the sphere is growing; it is an unstable factor of the interface when the interface is decaying.

关键词： solid-liquid interface spherical crystal convective flow crystal growth morphological stability

Study of proton resonances in ^(18)Ne via resonant elastic scattering of ^(17)F+p and its astrophysical implication

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science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 32-36页

作者： HE jianjun1, HU Jun1,2. xu ShiWei1, chen ZhiQiang1, ZHANG xueYing1, {2. JianSong1, YU XiangQing1, ZHANG LiYong1,2. LI Long1,2. YANG YanYun1,2. MA Peng1,2. ZHANG xueHeng1, HU ZhengGuo1, GUO ZhongYan1, xu Xing1,2. YUAN XiaoHua1, LU Wan1,2. YU YuHong1, ZANG YongDong1,2. TANG ShuWen1,2. YE RuiPing1,2. chen JinDa1,2. JIN ShiLun1,2. DU chengMing1,2. {2. ShiTao1,2. MA JunBing1,2. LIU LongXiang1,2. BAI Zhen1,2. LEI XiangGuo1, SUN ZhiYu1, ZHANG YuHu1, ZHOU XiaoHong1, xu HuShan1, SU Jun3, LI ErTao3, {2. HongWei4, TIAN WenDong4 & LI XiangQing5 1 Institute of Modern Physics (IMP), Chinese Academy of sciences, Lanzhou 730000, china 2.Graduate University of Chinese Academy of sciences, beijing 100049, china 3 china Institute of Atomic Energy (CIAE), beijing 102.13, china 4 Shanghai Institute of applied Physics (SINAP), Chinese Academy of sciences, Shanghai 2.1800, china 5 school of Physics and State Key Laboratory of Nuclear Physics and technology, Peking University, beijing 100871, china Institute of Modern Physics (IMP) Chinese Academy of Sciences Lanzhou China Graduate University of Chinese Academy of sciences Beijing China china Institute of Atomic Energy (CIAE) Beijing China Shanghai Institute of applied Physics (SINAP) Chinese Academy of Sciences Shanghai China school of Physics and State Key Laboratory of Nuclear Physics and technology Peking University Beijing China

The proton resonant properties in 18Ne, which determine the reaction rate of the key stellar 14O(α,p)17F reaction, have been studied by using a technique of proton resonant elastic scattering of 17F+p. A 4.2. MeV/nucleon 17F radioactive ion (RI) beam was produced via a projectile-fragmentation reaction, and separated by a Radioactive Ion Beam Line in Lanzhou (RIBLL). By bombarding a thick (CH2.n target, the energy spectra of the recoiled protons were measured by two ΔE-E silicon telescopes at the center-of-mass scattering angles of θc.m.≈175°±5°, θc.m.≈152.±8°, respectively. Several proton resonances in 18Ne were ob served clearly. A further R-matrix analysis of the experimental data is under way to determine the resonant parameters. The present work reports the preliminary results briefly.

关键词： resonant reaction reaction rate explosive burning accreting binary systems

The effect of far field flow on a spherical crystal growth in the undercooled melt

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Acta Mechanica Sinica 2008年第6期24卷 681-689页

作者： mingwen chen {2. wang Jianxin Xie Jian-Jun xu school of applied {2. University of Science and Technology Beijing Beijing 100083 China school of Materials science and Engineering University of Science and Technology Beijing Beijing 100083 China school of Mathematical sciences Nankai University Tianjin 300071 China Department of Mathematics and Statistics McGill University Montreal H3A 2K6 Canada

The effect of convective flow on a spherical crystal growth in the undercooled melt with a moderate far field flow is studied. The asymptotic solution of the evolution of the interface of the spherical crystal growth is obtained by the matched asymptotic expansion method. The analytic result shows that the convective flow in the undercooled melt has a strong effect on the evolution of spherical crystal growth. The convective flow induced by the far field flow makes the interface of the growing spherical crystal enhance its growth velocity in the upstream direction of the far field flow and inhibit growth in the downstream direction, and the interface of the decaying spherical crystal further decay in the upstream direction and inhibit decay in the downstream direction. The maximum growth velocity of the interface of the spherical crystal influenced by the far field flow is obtained.

关键词： Solid-liquid interface Spherical crystal Convective flow Crystal growth Undercooled melt

香辛料SYBR GREENⅠ染料实时聚合酶链式反应检测方法的建立及应用

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食品科学 2024年第12期45卷 269-275页

作者：杨晴丽王仁静张茹孟宪卓姚帮本陈赵然张旭方建军陈伟合肥工业大学食品与生物工程学院安徽合肥230601 安徽省产品质量监督检验研究院安徽合肥230051 衢州市食品药品检验研究院浙江衢州324000

目的:本研究致力于建立香辛料真实性成分的分子鉴定方法,为香辛料的掺假提供有效的鉴定和检测方法,在不同的使用条件下分别实现定性或半定量分析,为建立相关标准提供一定的基础技术支撑。方法:研究采用SYBR GREENⅠ染料实时聚合酶链式反... 详细信息

目的:本研究致力于建立香辛料真实性成分的分子鉴定方法,为香辛料的掺假提供有效的鉴定和检测方法,在不同的使用条件下分别实现定性或半定量分析,为建立相关标准提供一定的基础技术支撑。方法:研究采用SYBR GREENⅠ染料实时聚合酶链式反应(polymerase chain reaction,PCR)方法,通过设计特异性引物成功建立了特异性检测八角、茴香、胡椒和花椒的分析技术。结果:该方法能够特异性检测出八角、茴香、胡椒、花椒,Ct值在标准品体积分数0.001%~10%范围内线性关系良好。针对八角标准品,检测限为1%;针对茴香、花椒、胡椒标准品,最检测限均为0.001%。利用该方法对5份实际样本进行检测,分别在样本1中未检测出八角、茴香、胡椒、花椒;样本2.3、5中检测出八角、茴香、胡椒;样本4中检测出八角、茴香、胡椒、花椒。结论:本实验建立的SYBR GREENⅠ染料实时PCR方法灵敏度高、重复性好,可应用于实际样品的检测。

关键词：香辛料 SYBR GREENⅠ染料实时聚合酶链式反应检测

Advances in the Application of Perovskite Materials

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Nano-Micro Letters 2023年第10期15卷 334-381页

作者： Lixiu Zhang Luyao Mei Kaiyang wang Yinhua Lv Shuai Zhang Yaxiao Lian Xiaoke Liu Zhiwei Ma Guanjun Xiao Qiang Liu Shuaibo Zhai Shengli Zhang Gengling Liu Ligang Yuan Bingbing Guo Ziming chen Keyu Wei Aqiang Liu Shizhong Yue Guangda Niu Xiyan Pan Jie Sun Yong Hua Wu‑Qiang Wu Dawei Di Baodan Zhao {2. Tian Zhijie wang Yang Yang Liang Chu Mingjian Yuan Haibo Zeng Hin‑Lap Yip Keyou Yan Wentao xu Lu Zhu Wenhua Zhang Guichuan Xing Feng Gao Liming Ding Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190People’s Republic of China University of Chinese Academy of sciences Beijing 100049People’s Republic of China Department of Physics Link.ping University58183 Link.pingSweden Institute of applied Physics and Materials Engineering University of MacaoMacao 999078People’s Republic of China school of Materials science and Engineering Yunnan UniversityKunming 650091People’s Republic of China school of Microelectronics science and {2. Sun Yat-sen UniversityZhuhai 519082People’s Republic of China College of Electronic Information and Optical Engineering Nankai UniversityTianjin 300350People’s Republic of China Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems Harbin Institute of TechnologyShenzhen 518055People’s Republic of China school of Materials science and Engineering Nanjing University of Science and TechnologyNanjing 210094People’s Republic of China College of Optical science and Engineering Zhejiang UniversityHangzhou 310027People’s Republic of China State Key Laboratory of Superhard Materials Jilin UniversityChangchun 130012People’s Republic of China College of Electronic and Optical Engineering Nanjing University of Posts and TelecommunicationsNanjing 210023People’s Republic of China school of Chemistry Sun Yat-sen UniversityGuangzhou 510006People’s Republic of China school of Environment and Energy South China University of TechnologyGuangzhou 510000People’s Republic of China Department of Chemistry Imperial College LondonLondon W120BZUK College of Chemistry Nankai UniversityTianjin 300071People’s Republic of China Institute for Advanced Materials and technology University of Science and Technology BeijingBeijing 100083People’s Republic of China Institute of Semiconductors Chinese Academy of SciencesBeijing 100083People’s Republic of China school

Nowadays, the soar of photovoltaic performance of perovskite solar cells has set off a fever in the study of metal halide perovskite materials. The excellent optoelectronic properties and defect tolerance feature allow metal halide perovskite to be employed in a wide variety of applications. This article provides a holistic review over the current progress and future prospects of metal halide perovskite materials in representative promising applications, including traditional optoelectronic devices(solar cells, light-emitting diodes, photodetectors, lasers), and cutting-edge technologies in terms of neuromorphic devices(artificial synapses and memristors) and pressure-induced emission. This review highlights the fundamentals, the current progress and the remaining challenges for each application, aiming to provide a comprehensive overview of the development status and a navigation of future research for metal halide perovskite materials and devices.

关键词： Perovskites Optoelectronic devices Neuromorphic devices Pressure-induced emission

~1H(^(17)F,α)^(14)O反应截面测量

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原子核物理评论 2019年第1期36卷 37-42页

作者：贾宝路胡钧何建军许世伟 H.Yamaguchi D.Kahl 马朋苏俊王宏伟 T.Nakao Y.Wakabayashi T.Teranishi K.I.Hahn J.Y.Moon H.S.Jung T.Hashimoto A.A.chen D.Irvine C.S.Lee S.Kubono 中国科学院近代物理研究所兰州730000 中国科学院大学核科学与技术学院北京100049 中国科学院国家天文台北京100101 Center for Nuclear Study (CNS) University of Tokyo 中国原子能科学研究院北京102413 中国科学院上海应用物理研究所上海201800 RIKEN Nishina Center Department of Physics Kyushu University Department of science Education Ewha Womans University Department of Physics Chung-Ang University RCNP Osaka University Department of Physics & Astronomy McMaster University

^(14)O(α, p)^(17)F是天体X射线暴中重要的突破反应。本工作通过厚靶方法测量其逆反应~1H(^(17)F,α)^(14)O的反应截面来研究这一关键反应。本实验工作是在日本东京大学原子核科学研究中心(CNS)的低能次级束流线(CRIB)上完成的,后续的... 详细信息

^(14)O(α, p)^(17)F是天体X射线暴中重要的突破反应。本工作通过厚靶方法测量其逆反应~1H(^(17)F,α)^(14)O的反应截面来研究这一关键反应。本实验工作是在日本东京大学原子核科学研究中心(CNS)的低能次级束流线(CRIB)上完成的,后续的扣除本底实验是在兰州放射性束流线(RIBLL1)上完成的。CRIB实验是通过~2.(^(16)O,n)^(17)F转移反应产生^(17)F次级束,经过CRIB分离提纯之后,利用该次级束轰击氢气靶。在氢气靶后布置了三套望远镜探测器系统,用以探测不同实验角度的反冲α粒子,在数据处理的过程中经过动力学重构后得到了~1H(^(17)F,α)^(14)O反应在质心系能区E_(c.m.)=2.7～3.4 MeV的反应截面。实验结果在3 MeV以上的高能区与前人的薄靶实验数据是一致的,在低能区本工作获得了新的实验数据,倾向于支持干涉相消的理论预言结果。

关键词： X射线暴厚靶方法放射性核束反应截面激发函数