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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 {2.3.4 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 {12., Tianjin 3.0071, china 4 Department of Mathematics and Statistics, McGill {12., Montreal H3. 2.6, Canada 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 2K6 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 1. Institute of Modern Physics (IMP) Chinese Academy of Sciences Lanzhou 730000 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. China Institute of Atomic Energy (CIAE) Beijing 102413 China4. Shanghai Institute of Applied Physics (SINAP) Chinese Academy of Sciences Shanghai 201800 China5. School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 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. {3. Jianxin Xie Jian-Jun xu School of applied sciences 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

Geometric effect promoted hydrotalcites catalysts towards aldol condensation reaction

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Chinese Journal of Catalysis 2020年第8期41卷 1279-1287页

作者： Huimin wang Weihan Bing Chunyuan chen Yusen Yang Ming xu Lifang chen Lei Zheng Xiaolin Li Xin Zhang jianjun Yin Min Wei State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China china Tianchen Engineering Corporation {2. Research and Development Center Tianjin 300400China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China SINOPEC beijing Research Institute of Chemical Industry Beijing 100013China

In solid basic catalysis field,how to achieve optimized activity and desired stability through elaborate control over basic site properties remains a *** this work,taking advantage of the structure memory effect of layered double hydroxides(LDHs),rehydrated Ca4 Al1-x Gax-LDHs and Ca4 Al1-x Inx-LDHs catalysts were prepared and applied in aldol condensation reaction that isobutyraldehyde(IBD)reacts with formaldehyde(FA)to obtain hydroxypivalaldehyde(HPA).Notably,the resulting re-Ca4 Al0.90Ga0.10-LDHs exhibits an extraordinarily-high catalytic activity(HPA yield:72.),which is to our best knowledge the highest level in this *** weak Br?nsted basic site,7-coordinated Ca-OH group,which serves as an active site,catalyzes the condensation process and promotes the product *** on structure-property correlations demonstrate that Ga as a structural promoter induces a moderate expansion of the laminate lattice,which results in a significant increase in the concentration of weak basic sites in re-Ca4Al0.90Ga0.10-LDHs,accounting for its high catalytic *** work illuminates that geometric structure of basic active sites can be tuned via introducing catalyst additive,which leads to a largely improved performance of hydrotalcite solid basic catalysts towards aldol condensation reaction.

关键词： Solid basic catalyst Geometric structure Structural promoter Aldol condensation Reconstructed hydrotalcite material

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 technology 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

蓄热技术对可再生能源分布式能源系统的效益分析

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储能科学与技术 2021年第1期10卷 385-392页

作者：曹建军王俊张利勇刘亚奇凌浩恕王亮徐玉杰周学志陈海生神华国华(北京)分布式能源科技有限责任公司北京100025 中国科学院工程热物理研究所北京100190 中科储能(北京)咨询有限公司北京100190 国家能源大规模物理储能技术(毕节)研发中心贵州毕节551712

为了综合分析蓄热技术对可再生能源分布式能源系统的效益,本工作以大连某办公建筑群太阳能、风能、燃气互补的可再生能源分布式系统为研究对象,建立了蓄热技术与可再生能源分布式能源系统耦合评价模型,分析了蓄热技术对可再生能源分布... 详细信息

为了综合分析蓄热技术对可再生能源分布式能源系统的效益,本工作以大连某办公建筑群太阳能、风能、燃气互补的可再生能源分布式系统为研究对象,建立了蓄热技术与可再生能源分布式能源系统耦合评价模型,分析了蓄热技术对可再生能源分布式能源系统的电平衡、热平衡、燃料耗量及对环境温室效应、酸化效应和污染效应的影响,并利用静态经济性和动态经济性评价法,分析了水、导热油、耐火砖、水合盐、石蜡等蓄热技术应用的经济可行性。结果表明,在以电定热运行模式下,蓄热技术的引入对电平衡没有影响,但蓄热技术典型日可供暖142.1.14 kW·h,减小63.95%燃气锅炉补热量,节约182..74 m3.气耗量,一次能源节约率为13.16%,进而减轻3.2.65.90 g CO2.成的温室效应、2.8.3. g SO2.成的酸化效应和150.74 g PM2.5造成的污染效应;水、耐火砖、水合盐和石蜡蓄热技术具有较好的经济可行性,且以水蓄热技术最具优势,静态和动态投资回收期分别为4.91年和6.57年;导热油蓄热技术投资回收期较长,经济可行性较低。研究可为蓄热技术在分布式能源系统高效应用提供参考和依据。

关键词：蓄热技术分布式能源可再生能源节能环保经济性

一种长效生态抗菌剂用于高频接触物体表面消毒效果的评价

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天津科技 2022年第10期49卷 67-69,73页

作者：陈凤王东邓建军高利红徐敏杨弋四川大学华西第二医院四川成都610041 出生缺陷与相关妇儿疾病教育部重点实验室四川成都610041

为评价一种长效生态抗菌剂对医疗机构内高频接触物体表面的消毒效果,在某医院内随机选取3.高风险科室,分别使用长效生态抗菌剂和含氯消毒剂对室内高频接触物体表面进行消毒,采用ATP检测的方法依次比较消毒后2. h、1周、2.、3.、4周... 详细信息

为评价一种长效生态抗菌剂对医疗机构内高频接触物体表面的消毒效果,在某医院内随机选取3.高风险科室,分别使用长效生态抗菌剂和含氯消毒剂对室内高频接触物体表面进行消毒,采用ATP检测的方法依次比较消毒后2. h、1周、2.、3.、4周时间段内长效生态抗菌剂和含氯消毒剂的消毒效果。消毒前长效生态抗菌剂和含氯消毒剂检测区域ATP检测值差异无统计学意义;使用长效生态抗菌剂消毒后ATP检测值分别与消毒前比较差异有统计学意义(P2.%的物表ATP检测值合格,长效生态抗菌剂对高频接触物体表面具有持续抗菌消毒效果,且与含氯消毒剂具有同样的消毒效果。鉴于其对人体皮肤无刺激、无毒副作用,可减少日常工作中化学消毒剂的使用,进而可减少环境污染,是一种可推广应用的物体表面抗菌消毒剂。

关键词：长效生态抗菌剂含氯消毒剂物体表面消毒 ATP

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激光加工热压导光板网点构建与优化设计

光学技术 2020年第5期46卷 582-586页

作者：于文文王健王雪琨钱维莹曹建军高淑梅江南大学江苏省轻工光电工程技术研究中心江苏无锡214122 苏州天禄光科技股份有限公司江苏苏州215500

导光板的网点结构会直接影响背光模组的均匀性和亮度,不同的加工方法也会产生不同的网点结构。激光加工热压成型的导光板散射网点,因结构极其复杂,难以用光学设计软件直接进行仿真设计。提出基于仪器采集的网点表面信息,采用多个软件联... 详细信息

导光板的网点结构会直接影响背光模组的均匀性和亮度,不同的加工方法也会产生不同的网点结构。激光加工热压成型的导光板散射网点,因结构极其复杂,难以用光学设计软件直接进行仿真设计。提出基于仪器采集的网点表面信息,采用多个软件联合建模的方法,构建出一个可直接用于导光板仿真设计的网点模型。利用此网点模型优化设计背光模组,加工成产品测试发光均匀度达到88.8%,与仿真结果吻合。研究结果解决了企业以往只能依靠多次加工实验对导光板进行优化设计的问题,极大地减少研发时间,节省了生产成本。

关键词：应用光学光学设计背光模组导光板网点结构