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现浇楼板厚度对板筋参与梁负弯矩区受力的影响

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低温建筑技术 2017年第6期39卷 11-14页

作者：唐琪琛公茂盛谢礼立中国地震局工程力学研究所中国地震局地震工程与工程振动重点实验室哈尔滨150080 哈尔滨工业大学土木工程学院哈尔滨150090

为探究现浇楼板厚度对板筋参与梁负弯矩区受力的影响,采用ABAQUS有限元软件,建立了不同板厚的6个钢筋混凝土(RC)框架结构精细化模型,通过侧向加载分析了板厚对板筋参与梁负弯矩区受力的影响程度。结果表明:板筋对梁负弯矩区受力的参与... 详细信息

为探究现浇楼板厚度对板筋参与梁负弯矩区受力的影响,采用ABAQUS有限元软件,建立了不同板厚的6个钢筋混凝土(RC)框架结构精细化模型,通过侧向加载分析了板厚对板筋参与梁负弯矩区受力的影响程度。结果表明:板筋对梁负弯矩区受力的参与作用随板厚的增大而减小;板底筋对梁负弯矩区受力的参与作用要弱于板顶筋,且随着板厚增加,两者应力差越大。结果可供确定RC框架结构现浇楼板的有效翼缘宽度参考。

关键词： RC框架结构现浇楼板板筋

Trimetallic oxyhydroxides as active sites for large-current-density alkaline oxygen evolution and overall water splitting

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Journal of Materials Science & Technology 2022年第15期110卷 128-135页

作者： Lei Chen Yunpeng Wang Xin Zhao Yuchao Wang Qian Li qichen Wang Yougen tang Yongpeng Lei State Key Laboratory of Powder Metallurgy Hunan Key Laboratory of Two-Dimensional MaterialsCentral South UniversityChangsha 410083China Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Physics and Electronics Hunan Key Laboratory for Super-micro structure and Ultrafast ProcessCentral South UniversityChangsha 410083China

Earth-abundant electrocatalysts for large-current-density water splitting under alkaline condition are *** evolution reaction,which is a bottleneck of the overall water splitting,faces the problems of complicated reconstruction and deficiency in rational design of active ***,we report a series of transition metal chalcogenides for alkaline *** them,FeCoNi(S)displayed a low overpotential of 293 m V to deliver a current density of 500 m A cm^(-2),which is in the top level of non-precious metal based OER electrocatalysts.A combination of(ex)in situ characterizations and DFT calculation shows that Ni(Fe,Co)trimetallic oxyhydroxides were the active sites for highly-efficient ***,for FeCoNi(S),when used as a bifunctional catalyst for water splitting,it only required a cell voltage of 1.84 V to deliver~500 m A cm^(-2) with extraordinary long-term stability over 2000 *** work provides the comprehension of high-efficiency,robust catalysts for OER and overall water splitting at large current densities in alkaline media.

关键词： Oxygen evolution Active sites Surface reconstruction Large current density Overall water splitting

Potential active sites of Mo single atoms for electrocatalytic reduction of N_(2)

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Chinese Chemical Letters 2021年第1期32卷 53-56页

作者： Lei Chen Chaozheng He Ran Wang Qian Li Jian Zeng Wei Liu Yuchao Wang qichen Wang Tong Ye Yougen tang Yongpeng Lei State Key Laboratory of Powder Metallurgy Hunan Provincial Key Laboratory of Chemical Power SourcesCollege of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China Institute of Environmental and Energy Catalysis School of Materials Science and Chemical EngineeringXi'an Technological UniversityXi'an 710021China State Key Laboratory of Fine Chemicals Department of ChemistrySchool of Chemical EngineeringDalian University of TechnologyDalian 116024China Shaanxi Key Laboratory of Optoelectronic Functional Materials and Devices School of Materials Science and Chemical EngineeringXi'an Technological UniversityXi'an 710021China School of Material Science and Engineering Central South University of Forestry and TechnologyChangsha 410004China

Single atom catalysts(SACs) with isolated metal atoms dispersed on supports exhibit distinctive performances for electrocatalysis *** designable realization of well-dispersed single metal atoms is still a great challenge owing to their ease of ***,Mo single atomic sites(Mo-N_(3)C)combined with some ultrasmall Mo_(2)C/MoN clusters(Mo-SA/Mo_(2)C-MoN-Cs,mean diameter <2 nm) on nitrogen-doped porous carbon were synthesized via a simple pyrolysis of bimetallic Zn/Mo metalorganic frameworks.X-ray absorption near edge spectra(XANES) in combination with various characterizations show that most of Mo species in sample exist in the form of single sites and the exact structure is Mo-N_(3)*** functional theory(DFT) calculation further shows that as the number of Ncoordination in the Mo-NxC moieties increases,the positive cha rge of Mo atoms *** single Mo atoms in Mo-N_(3)C have the best capability of N_(2) adsorption,which may serve as main active sites for further electrochemical N2 reduction.

关键词： Single atom catalysts N_(2)reduction reaction Electrocatalysis Density functional theory Active sites

光源的选择对水溶性磺酸卟啉光催化对萘二酚类物质催化性能的影响

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高等学校化学学报 2021年第6期42卷 1933-1941页

作者：朱琪琛熊明陶思羽唐思危任奇志上海交通大学化学化工学院上海200240 无锡小天鹅电器有限公司研发中心无锡214028

制备了水溶性磺酸卟啉(TPPS,TMPPS)及其铁配合物(FeTPPS).以过氧化氢为氧源、碘钨灯为光源,水溶性磺酸卟啉可以高效光催化氧化1,5-萘二酚,产物为5-羟基-1,4-萘二醌.测定了卟啉的荧光量子产率及寿命,分析了催化机理.选择波长在350~650 n... 详细信息

制备了水溶性磺酸卟啉(TPPS,TMPPS)及其铁配合物(FeTPPS).以过氧化氢为氧源、碘钨灯为光源,水溶性磺酸卟啉可以高效光催化氧化1,5-萘二酚,产物为5-羟基-1,4-萘二醌.测定了卟啉的荧光量子产率及寿命,分析了催化机理.选择波长在350~650 nm区间内6个波段和功率在0~20 W区间内4种功率的光源,探索了不同波段及功率的光源对卟啉光催化活性的影响.研究结果表明,不同波段的光源对卟啉光催化1,5-萘二酚的催化活性顺序为λ380—385>λ360—370>λ580—585>λ620—630>λ492—577>λ450—470,该活性顺序与卟啉的紫外-可见吸收密切相关;当使用相同波段光源时,卟啉配体催化氧化1,5-萘二酚的反应速率常数与功率呈良好的线性关系;卟啉铁配合物随着光源功率的增大,其催化活性与光解程度有直接关系.

关键词：卟啉 1 5-萘二酚 meso-四(3-甲氧基-4-磺酸苯基)卟啉的铁配合物光解

PREPARATION AND CRYSTAL STRUCTURE OF TETRAKIS（TETRAHYDROFURAN） MAGNESIUM DICHLORIDE[MgCl2·4THF]

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Chinese Journal of Structural Chemistry 1987年第1期 43-46页

作者： Huang qichen Qian Yanlong Zhuang Junming tang Youqi Shanghai Institute of Organic Chemistry, Academia Sinica Department of Chemistry, Beijing University

INTRODUCTION. The magnesim, dichloride is widely used as a supporter of the highly efficient Ziegler-Natta catalyst with ether or ester as a donor. To study the interaction between the supporter and the donor would lead to a better understanding of the mechenisms of stereoregular polymerization. Here we wish to report the preparation and X-ray crystal structure of MgCl4THF, which is the first example of the MgClcomplex uncontaining coordinated water or solvent water.

关键词： THF PREPARATION AND CRYSTAL STRUCTURE OF TETRAKIS TETRAHYDROFURAN MAGNESIUM DICHLORIDE[MgCl2

环己烷中牛胰蛋白酶与正戊胺复合物的晶体结构

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化学学报 2003年第9期61卷 1393-1398页

作者：巫广腾黄其辰朱广宇钱民协唐有祺北京大学化学与分子工程学院化学生物学系北京100871

丝氨酸蛋白酶是有机溶媒中研究酶促反应的主要对象之一 .其中的胰蛋白酶在生物体内有重要的作用 ,对其抑制剂如苯甲脒衍生物的研究可应用于治疗很多疾病 .在水溶液中包括正戊胺在内的开链脂肪胺类小分子对胰蛋白酶的抑制能力有限 ,不能... 详细信息

丝氨酸蛋白酶是有机溶媒中研究酶促反应的主要对象之一 .其中的胰蛋白酶在生物体内有重要的作用 ,对其抑制剂如苯甲脒衍生物的研究可应用于治疗很多疾病 .在水溶液中包括正戊胺在内的开链脂肪胺类小分子对胰蛋白酶的抑制能力有限 ,不能生成复合物 .我们对浸泡在含有正戊胺的环己烷中的β 牛胰蛋白酶的晶体结构进行了测定 ,分辨率为 0 .2nm ,并与水相中同样处理的晶体作了比较 .结果表明 ,正戊胺于环己烷中和 β 牛胰蛋白酶有强结合作用 ,一个戊胺分子结合到酶活性中心 ;另一个结合在 β 牛胰蛋白酶的表面 ,与也被结合的硫酸根形成氢键 .此X射线蛋白质晶体结构分析提供了一个例子 ,在有机溶剂中可用弱抑制剂的探针小分子研究其和蛋白的结合情况 ,以及描绘蛋白质表面的结合位点 .这些研究可以为搜索弱抑制剂提供有用的结构信息 .

关键词：环己烷 β牛胰蛋白酶正戊胺晶体结构 X射线蛋白质有机溶剂药物设计抑制剂

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江边水电站环境保护措施

水力发电 2012年第6期38卷 5-7页

作者：汤优敏王蕾蒋波廖琦琛中国水电顾问集团华东勘测设计研究院浙江杭州310014

介绍了江边水电站建设过程中环境保护措施、环境管理与监控措施落实情况,采取的下泄生态流量、生态流量在线测系统、鱼类增殖站、垃圾焚烧站等四大环境保护措施,有效地预防和减缓了工程建设造成的环境影响,可作为其他水电工程借鉴。

关键词：环境保护生态流量鱼类增殖站垃圾焚烧站江边水电站

基于移动互联网的新型实验教学平台管理系统构建研究

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普洱学院学报 2020年第3期36卷 54-56页

作者：唐秀忠李其琛杨根成普洱学院云南普洱665000

伴随着素质教育改革的深入推进,移动互联网技术的快速发展,应用型人才培养需要引入移动互联网技术,在传统网络教学平台的基础上,搭建具有良好师生互动性的新型实验教学平台管理系统,构建仿真的实验模拟课堂,培养动手操作实践能力,实现... 详细信息

伴随着素质教育改革的深入推进,移动互联网技术的快速发展,应用型人才培养需要引入移动互联网技术,在传统网络教学平台的基础上,搭建具有良好师生互动性的新型实验教学平台管理系统,构建仿真的实验模拟课堂,培养动手操作实践能力,实现知识的有效转化,提高实验教学的丰富性、实践性和全面性,激发学生的学习兴趣,提高教学质量。

关键词：移动互联网新型实验教学平台管理系统构建研究

Auxin response factor 6A regulates photosynthesis,sugar accumulation,and fruit development in tomato

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Horticulture Research 2019年第1期6卷 678-693页

作者： Yujin Yuan Xin Xu Zehao Gong Yuwei tang Mengbo Wu Fang Yan Xiaolan Zhang Qian Zhang Fengqing Yang Xiaowei Hu qichen Yang Yingqing Luo Lihua Mei Wenfa Zhang Cai-Zhong Jiang Wangjin Lu Zhengguo Li Wei Deng Key Laboratory of Plant Hormones and Development Regulation of Chongqing School of Life SciencesChongqing University401331 ChongqingChina School of Chemistry and Chemical Engineering Chongqing University400044 ChongqingChina College of Basic Science Tianjin Agricultural University300384 TianjinChina Department of Plant Sciences University of CaliforniaDavisCA 95616USA Crops Pathology and Genetics Research Unit United States Department of AgricultureAgricultural Research ServiceDavisCA 95616USA State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables College of HorticultureSouth China Agricultural University510642 GuangzhouChina

Auxin response factors(ARFs)are involved in auxin-mediated transcriptional regulation in *** this study,we performed functional characterization of SlARF6A in ***6A is located in the nucleus and exhibits transcriptional activator *** of SlARF6A increased chlorophyll contents in the fruits and leaves of tomato plants,whereas downregulation of SlARF6A decreased chlorophyll contents compared with those of wild-type(WT)*** of chloroplasts using transmission electron microscopy indicated increased sizes of chloroplasts in SlARF6A-overexpressing plants and decreased numbers of chloroplasts in SlARF6A-downregulated *** of SlARF6A increased the photosynthesis rate and accumulation of starch and soluble sugars,whereas knockdown of SlARF6A resulted in opposite phenotypes in tomato leaves and ***-sequence analysis showed that regulation of SlARF6A expression altered the expression of genes involved in chlorophyll metabolism,photosynthesis and sugar ***6A directly bound to the promoters of SlGLK1,CAB,and RbcS genes and positively regulated the expression of these *** of SlARF6A also inhibited fruit ripening and ethylene production,whereas downregulation of SlARF6A increased fruit ripening and ethylene ***6A directly bound to the SAMS1 promoter and negatively regulated SAMS1 *** together,these results expand our understanding of ARFs with regard to photosynthesis,sugar accumulation and fruit development and provide a potential target for genetic engineering to improve fruit nutrition in horticulture crops.

关键词： sugar metabolism photosynthesis