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[BxAl(13-x)]^-(x=0～13)二元团簇的密度泛函理论研究

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化学学报 2016年第9期74卷 758-763页

作者：黄敏徐畅程龙玖安徽大学化学化工学院合肥260301

采用遗传算法(Genetic algorithm,GA)对B-Al二元团簇[B_xAl_(13-x)]^-(x=0～13)进行了全局结构搜索,并在密度泛函理论(Density Functional Theory,DFT)下对其进行了优化计算.结果表明在二元团簇中,随着硼原子的数量逐渐增加,团簇的结构... 详细信息

采用遗传算法(Genetic algorithm,GA)对B-Al二元团簇[B_xAl_(13-x)]^-(x=0～13)进行了全局结构搜索,并在密度泛函理论(Density Functional Theory,DFT)下对其进行了优化计算.结果表明在二元团簇中,随着硼原子的数量逐渐增加,团簇的结构由二十面体(3D)逐渐转化为准平面(2D)且团簇结构由B与Al原子的比例所决定的.当x=0~7时,Al原子占多数,团簇保持3D结构;反之团簇呈现2D构型;在x=7~8时,团簇的结构发生由3D向2D的转变.能量决定着团簇的稳定性(例如相对能量).能量越小,其结构越稳定.在计算相对能量Erel,当x=1时,其相对能量最低,团簇结构最稳定.为了进一步了解团簇的稳定性,计算了[BxAl13-x]-团簇的HOMO-LUMO能级差(EH-L)和垂直电离能(Vertical Detachment Energies,VDE),并且发现它们的值在整体上是随着B原子数量的增加而减小,表明其团簇的稳定性逐渐减弱.在所有的团簇中,BAl_(12)^-的能级差最大,结构最稳定.因此文章中对其进行了分子轨道分析,发现当一个B原子替代了Al_(13)^-团簇中的中心Al原子时,所得到的BAl_(12)^-的电子壳层结构的1s^2和1p^6几乎和Al_(13)^-团簇保持一致.此外,对于x=13时的准平面全硼团簇B_(13)^-,文章中用适应性自然密度划分(Adaptive Natural Density Partitioning,Ad NDP)对其化学成键进行了分析,结果显示B_(13)^-有8个π电子,具有π反芳香性.

关键词：密度泛函理论 [BxAl13-x]-(x=0~13)团簇优化分子轨道适应性自然密度划分

舞台防火隔离幕驱动机液压阻尼系统设计及阻尼力计算

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液压与气动 2013年第4期37卷 49-52页

作者：徐长城甘肃工大舞台技术工程有限公司甘肃兰州730050

该文根据目前舞台防火隔离幕驱动机使用现状,设计了一种新型液压阻尼系统,基于阻尼系统的作用,使防火幕幕体能以多级速度自动切换实现自由下降。对阻尼系统在幕体最大自由下降速度时(阻尼回路阀口全开时)的阻尼力进行了分析计算,确定了... 详细信息

该文根据目前舞台防火隔离幕驱动机使用现状,设计了一种新型液压阻尼系统,基于阻尼系统的作用,使防火幕幕体能以多级速度自动切换实现自由下降。对阻尼系统在幕体最大自由下降速度时(阻尼回路阀口全开时)的阻尼力进行了分析计算,确定了提升幕体的钢丝绳所需的最小拉力。

关键词：防火幕驱动机阻尼系统设计阻尼计算钢丝绳拉力确定

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H_∞控制主动悬架平顺性仿真分析

计算机仿真 2012年第11期29卷 374-377页

作者：宋刚许长城招商局重庆交通科研设计院动力所重庆400067

关于改善车辆的行驶平顺性问题,由于行驶路面激励,存在不稳定因素,应调节悬架系统的刚度和阻尼,改善行驶的平顺性。为解决上述问题,提出采用主动悬架H∞输出反馈控制策略。根据线性矩阵不等式方法,在控制器设计中,假定悬架动行程及车身... 详细信息

关于改善车辆的行驶平顺性问题,由于行驶路面激励,存在不稳定因素,应调节悬架系统的刚度和阻尼,改善行驶的平顺性。为解决上述问题,提出采用主动悬架H∞输出反馈控制策略。根据线性矩阵不等式方法,在控制器设计中,假定悬架动行程及车身竖向加速度可以量测,同时考虑量测噪声;在控制输出向量选取上,以降低车身竖向加速度响应为目标,同时兼顾悬架最大动行程及轮胎动挠度。对于控制系统的数值仿真,通过引入虚拟激励,直接由道路谱得到车辆响应的精确功率谱密度。数值仿真结果表明,具有H∞输出反馈控制器的主动悬架对车辆行驶平顺性的改善有良好的效果。

关键词：主动悬架平顺性输出反馈虚拟激励功率谱

Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期68卷 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang Yan cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

关键词： photoactive metal complexes earth-abundant metals nonprecious metal complexes luminescence photochemistry

Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai Liu Wen-Qiang xu Ying-Tong Di Man-cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

新时代互联网给高校学生管理带来的机遇与挑战

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集宁师范学院学报 2022年第6期44卷 13-18页

作者：许长城莆田学院保卫处福建莆田351100

互联网背景下,丰富的信息资源和多样的媒介载体都可为高校学生管理工作使用,互联网还以其特有的去中心化、多样化、共享化等特征促进学生管理工作向扁平化、丰富性及精细化发展。互联网对管理工作理念的冲击、对管理者能力的要求、对管... 详细信息

互联网背景下,丰富的信息资源和多样的媒介载体都可为高校学生管理工作使用,互联网还以其特有的去中心化、多样化、共享化等特征促进学生管理工作向扁平化、丰富性及精细化发展。互联网对管理工作理念的冲击、对管理者能力的要求、对管理的精准化要求、对管理环境的影响等,阻碍了传统学生管理工作的顺利推进,给高校学生管理工作带来挑战。为有效应对各类挑战,高校及管理者应协同努力,探究互联网背景下学生管理工作应有的理念和模式,从具备互联网思维角度入手,探究管理工作的正确发展方向,优化管理者队伍建设,尊重学生主体地位,构建网络舆情监管制度,引领和保障学生管理工作在互联网环境下的顺利落实。

关键词：互联网高校大学生学生管理

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福建省新建本科院校专业结构分析优化与思考

莆田学院学报 2013年第3期20卷 85-88页

作者：许长城莆田学院教务处福建莆田351100

分析福建省新建本科院校专业结构现状及其存在的问题,提出应根据学校办学定位,通过科学制定专业建设规划、建立专业建设服务平台和开展专业评估,以促进福建省新建本科院校专业结构优化,提高专业建设水平和人才培养质量。

关键词：福建省新建本科院校专业结构结构优化

新建本科院校专业建设的现状与思路——以莆田学院为例

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莆田学院学报 2009年第1期16卷 97-100页

作者：许长城莆田学院教务处福建莆田351100

指出专业建设是新建本科院校发展的核心,针对莆田学院的专业建设进行分析,围绕专业建设存在问题,提出专业建设的若干发展思路与措施。

关键词：新建本科院校专业建设思路

Constructing 2D bismuth-based heterostructure for highly efficient photocatalytic CO2 reduction

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Tungsten 2025年第1期7卷 71-79页

作者： Ruo-Hang xu Hao-Yu Jiang Dan-Dan Cui Kun-Rong Du Hong-Run Zhang Sheng-Jie xu Ya-Qi Li Zhi-Zhen Ren Liang Wang Wei-chang Hao Yi Du School of Physics and BUAA-UOW Joint Research Centre Beihang University Shenzhen Institute of Beihang University Centre for Catalysis and Clean Energy School of Environment and Science Griffith University

Reforming carbon dioxide（CO2） into fuels and valuable chemicals using solar energy holds significant potential for emission reduction and addressing energy supply *** recombination of photocarriers remains a major obstacle,however,to enhancing solar energy conversion efficiency in the photocatalytic reaction *** two-dimensional materials,constructing heterogeneous structures has emerged as an effective strategy to enhance the separation of photoexcited carriers by leveraging the internal electric field at the heterogeneous ***,we present a facile strategy for preparing Bi4NbO8Br/Bi2WO6plate-on-plate Z-scheme junctions with a strong internal electric field by in situ *** unique heterostructure facilitates efficient separation and transport of photoexcited charges by harnessing the internal electric field induced by chemical bonding at the lateral ***,the Bi4NbO8Br/Bi2WO6heterostructure exhibits enhanced CO2photoreduction properties,along with a CO yield rate of approximately 35 μmol·g-1·h-1under full light *** work offers novel insights into the synthesis of unique hetero structures intended to enhance the efficiency of photocatalytic CO2reduction.

关键词： Bi4NbO8Br/Bi2WO6 CO2 reduction Heterostructures Photocatalysts