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Origin of d-π Interaction in Cobalt（ll） Porphyrins under Synergistic Effects of Core Contraction and Axial Ligation： Implications for a Ligand Effect of Natural Distorted Tetrapyrrole

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Chinese Journal of Chemistry 2016年第9期34卷 910-918页

作者： Qiuhua Liu Xi Zhang Wennan Zeng Jianxiu Wang zaichun zhou College of Chemistry and Chemical Engineering Central South University Changsha Hunan 410083 China Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of the Ministry of Education School of Chemistry and Chemical Engineering Hunan University of Science and Technology Xiangtan Hunan 411201 China

The reactivity of the metalloporphyrins was closely related to their ligand effect at axial position. The electronic properties of six model Co（II） porphyrins are investigated by spectral and electrochemical methods. Structural parameters of the COOI） complexes are directly obtained from their crystal structures. We demonstrate that the unpaired 3d electron of low-spin Co（II） ions in nonplanar Co（II） porphyrin complexes activated by core contraction of porphyrin macrocycles can be further activated by the axial ligation of imidazole. The activated electron can combine with a n orbital of the porphyrin ring to form a new d-π orbital, which can induce the Q-band of Co（II） porphyrins to visibly split. Addition of imidazole causes the Co（II）/Co（III） and Co（II）/Co（I） reactions to shift to more negative potential. Our results indicate that strong axial ligation and core contraction both play important roles in electron transfer in redox catalysis involving Co（II） complexes.

关键词： electronic structure metalloporphyrin synergistic effect ligand effect biomimicry

A trans-ortho asymmetrically di-strapped metalloporphyrin integrating three key structural features of ligand in heme

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Chinese Chemical Letters 2023年第10期34卷 140-145页

作者： Qiuhua Liu Junhao Gao Yusheng Zhang Xin Liu Xi Zhang Qin Lin Wennan Zeng zaichun zhou Key Laboratory of Theoretical Organic Chemistry and Functional Molecules Ministry of Education School of Chemistry and Chemical Engineering Hunan University of Science and TechnologyXiangtan 411201China

Heme responsible for the dioxygen fixation,transport and conversion is a metalloporphyrin complex highly dependent on its diverse geometry of *** this work,a trans-ortho-di-strapped zinc porphyrin with dome-like deformation was synthesized by thermodynamically controlling the formation of transprecursor of *** single-crystal structure demonstrated that the asymmetric treatment of porphyrin achieves three goals of creating two secondary coordination sphere(SCS)bulks,maintaining a unique dome deformation,and making atomic out-of-plane *** this way,this metallic complex integrates at least three key features of the pocket structure,the differentiated axial ligations,and the ring distortion,making it an ideal heme analog.

关键词： Supramolecular effect Heme analog Pocket effect Axial ligation Ring distortion

冷指结晶法去除LiCl熔盐中的碱土金属Sr、Ba

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核技术 2024年第3期47卷 37-46页

作者：林钦王玉娇程明孙波付海英窦强周金豪周再春刘秋华理论有机化学与功能分子教育部重点实验室和化学化工学院湖南科技大学湘潭411201 中国科学院上海应用物理研究所上海201800 东方电气成都氢燃料电池科技有限公司成都610000 中国科学院大学北京100049 上海科技大学上海201200

快堆乏燃料干法后处理中会产生含多种金属元素的LiCl废盐,分离废盐中的金属杂质既可净化熔盐,有利于盐的循环利用,又可减小废盐量,实现废物最小化。利用自行研制的冷指结晶装置,探索了LiCl熔盐中Sr、Ba两种碱土金属的分离和分离中的影... 详细信息

快堆乏燃料干法后处理中会产生含多种金属元素的LiCl废盐,分离废盐中的金属杂质既可净化熔盐,有利于盐的循环利用,又可减小废盐量,实现废物最小化。利用自行研制的冷指结晶装置,探索了LiCl熔盐中Sr、Ba两种碱土金属的分离和分离中的影响因素,并结合Fluent软件模拟确定较佳的分离工艺,进一步明确LiCl分离碱土金属的规律。研究表明,影响冷指结晶法分离效果的主要因素为熔盐初始温度,当熔盐温度高于660℃时,Sr、Ba去除率较佳;同时发现熔盐中Sr、Ba含量低于0.55%(w/w)时,其去除效率均可超过80%。进一步研究发现熔盐晶体不同部位的Sr、Ba去除效果不同,其中结晶盐顶部的杂质分离效果最佳,底部及内层的熔盐分离效果较差。含有Sr、Ba的LiCl熔盐较佳分离条件为温度660~670℃,气体流速10 L·min^(−1),生长时间20 min,此时LiCl盐中Sr、Ba的去除率可达90%。实验结果证实了冷指结晶法从电解质废熔盐中纯化溶剂盐的可行性,可为纯化废盐、实现熔盐的重复利用提供参考。

关键词： LiCl熔盐冷指碱土金属分离

单取代烷烃定量结构保留相关研究中的分子结构分区处理方法

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色谱 2005年第4期23卷 329-335页

作者：曹晨忠霍平高硕周再春湖南科技大学化学化工学院湖南湘潭411201

将单取代烷烃RX(X=卤素,OH,SH,NH2等)分子结构分为两个区域(R和X)来提取分子结构参数,从三方面影响因素(烷基R、取代基X、R与X的相互作用)来定量关联RX的气相色谱保留时间。实验测定了37种单取代烷烃RX的气相色谱保留时间,并以键连接矩... 详细信息

将单取代烷烃RX(X=卤素,OH,SH,NH2等)分子结构分为两个区域(R和X)来提取分子结构参数,从三方面影响因素(烷基R、取代基X、R与X的相互作用)来定量关联RX的气相色谱保留时间。实验测定了37种单取代烷烃RX的气相色谱保留时间,并以键连接矩阵特征根之和EVM、烷基极化效应指数PEI、取代基质量分数w和取代基上氢原子所带部分正电荷ΔNH4个参数为变量,建立了定量结构保留相关模型。该模型具有良好的预测能力和外推能力,对醇在不同色谱柱上的保留指数进行了预测,结果与测定值符合得较好。

关键词：气相色谱定量结构-保留相关键连接矩阵极化效应指数结构分区单取代烷烃

Inherent thermal-responsive strategies for safe lithium batteries

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Journal of Energy Chemistry 2024年第2期89卷 519-534,I0012页

作者： Jia-Xin Guo Chang Gao He Liu Feng Jiang zaichun Liu Tao Wang Yuan Ma Yiren Zhong Jiarui He Zhi Zhu Yuping Wu Xin-Bing Cheng School of Energy and Environment Southeast UniversityNanjing 211189JiangsuChina School of Chemistry and Materials Science Nanjing University of Information Science and TechnologyNanjing 210044JiangsuChina

Safe batteries are the basis for next-generation application scenarios such as portable energy storage devices and electric vehicles,which are crucial to achieving carbon ***,separators,and electrodes as main components of lithium batteries strongly affect the occurrence of safety *** materials,which can respond to external stimuli or environmental change,have triggered extensive attentions recently,holding great promise in facilitating safe and smart *** review thoroughly discusses recent advances regarding the construction of high-safety lithium batteries based on internal thermal-responsive strategies,together with the corresponding changes in electrochemical performance under external ***,the existing challenges and outlook for the design of safe batteries are presented,creating valuable insights and proposing directions for the practical implementation of safe lithium batteries.

关键词： Lithium battery Thermal safety Thermal runaway Thermal-responsive

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岩溶石漠化地区生态环境演变及驱动力分析

森林与环境学报 2024年第3期44卷 298-307页

作者：范金明张超钱慧朱夏力邓再春刘佰艳西南林业大学林学院云南昆明650224 云南省山地农村生态环境演变与污染治理重点实验室云南昆明650224

以云南省东南部典型石漠化地区砚山县为研究区,基于遥感手段反演和分析2000—2020年砚山县生态环境质量的演变过程,研究影响当地生态环境变化的主要驱动因子,旨在为石漠化地区生态环境定量评价提供方法借鉴。基于谷歌地球引擎(GEE)平台... 详细信息

以云南省东南部典型石漠化地区砚山县为研究区,基于遥感手段反演和分析2000—2020年砚山县生态环境质量的演变过程,研究影响当地生态环境变化的主要驱动因子,旨在为石漠化地区生态环境定量评价提供方法借鉴。基于谷歌地球引擎(GEE)平台提供的陆地卫星(Landsat)数据构建并计算研究区2000—2020年遥感生态指数,使用地理探测器量化主要驱动因子对生态环境质量的影响程度。结果表明:(1)2000、2010、2020年砚山县遥感生态指数均值为0.46、0.44、0.57,2000—2020年生态环境质量改善,改善比例为57.28%;(2)2000、2010、2020年砚山县石漠化整体状况有所改善,石漠化面积减少1181.77 km^(2);(3)2000—2020年石漠化、土地利用是生态环境的主要驱动因子;土地利用与石漠化交互作用对生态环境质量演变的解释力最强。2000—2020年砚山县生态环境质量逐步改善;在生态环境治理中应重点关注岩溶石漠化、土地覆盖类型稳定性的影响。

关键词：遥感生态指数生态环境质量演变过程驱动力石漠化

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闸北不夜城绿地设计简介

上海建设科技 2003年第1期 29-29,38页

作者：许华林周在春闸北区绿化管理局上海市园林设计院

不夜城绿地位于天目西路-华康路-共和路-华盛路-南北高架路至长安路之间近似三角形的地块,面积约4.3hm2.它地处不夜城商业区的东部,周边高层建筑密集,公共绿地十分缺乏.地块的北部和东部为城市主干道天目西路和共和新路,西部和南部为居... 详细信息

不夜城绿地位于天目西路-华康路-共和路-华盛路-南北高架路至长安路之间近似三角形的地块,面积约4.3hm2.它地处不夜城商业区的东部,周边高层建筑密集,公共绿地十分缺乏.地块的北部和东部为城市主干道天目西路和共和新路,西部和南部为居住区和待开发的临时绿地.绿地从选址到实施,历时3年,建设方案几易其稿,最后在综合各方面专家的意见和绿地现有状况条件下,提出了建设全新的城市景观绿地的框架.希望通过绿地的建设,优化闸北区,特别是不夜城地区商圈及周边地区良好的投资环境,形成具有闸北区特色的繁华都市景观,为市民提供良好的绿化文化空间和休闲娱乐场所.

关键词：城市景观绿化城市设计地域文化

An Aqueous Asymmetric Supercapacitor Based on Activated Carbon and Tungsten Trioxide Nanowire Electrodes

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Chinese Journal of Chemistry 2017年第1期35卷 61-66页

作者： Xinhai Yuan Bingwei Chen Xiongwei Wu Jun Mo zaichun Liu Zhengyong Hu Zhonghua Liu Chunjiao zhou Haijun Yang Yuping Wu College of Science National Research Center of Engineering Technology for Utilization of Functional Ingredients from Botanica College of Agronomy College of Plant Protection Hunan Agricultural University Changsha Hunan 410128 China Department of Chemistry Fudan University Shanghai 200433 China College of Energy and Institute for Electrochemical Energy Storage Nanjing Tech University Nanjing Jiangsu 211816 China

An asymmetric supercapacitor （ASC） was assembled by using an activated carbon as positive electrode and WO3 nanowire as negative electrode, and its electrical performances were tested in voltage windows ranging from 0 to 1.5 V. A high specific capacitance of 51 Fog-1 could be achieved at the current density of 0.25 A·g-1 . Moreover, the ASC displays a good cycling stability with 86% of capacitance retention after 800 cycles, its energy density can be up to 11.9 Wh·kg-1 at the power density of 210 W·kg -1, and remains 7.7 Wh·kg-1 at a power density of 1250 W· kg-1. The excellent electrical performance is perhaps due to the crystal orientation of （001） planes for the WO3 nanowire, which favors the rapid reaction between W（VI） and H＋ cations. This aqueous asymmetric WO3//AC supercapacitor is promising for practical applications due to its easy preparation of WO3.

关键词： asymmetric supercapacitor tungsten trioxide nanowire

Direct Asymmetric Aldol Reaction Co-catalyzed by Amphiphilic Prolinamide Phenol and Lewis Acidic Metal on Water

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Chinese Journal of Chemistry 2013年第2期31卷 247-255页

作者： Tao Zhang Yunxiao Zhang zaichun Li Zhongtai Song Hao Liu Jingchao Tao College of Chemistry and Molecular Engineering Zhengzhou University 75 Daxue Road Zhengzhou Henan 450052 China

An approach based on combinations of various water compatible Lewis acids and lipophilic group containing amphiphilic prolinamide co-catalysts has been evaluated for the direct asymmetric Aldol reaction. From the broad screening of chloride salts from alkali metal to transition metal, LiC1, ZnCI2 and SnCI2 lead to the highest stereoselectivities. The optimized catalytic conditions （10 mol% prolinamide with 10 mol% MC12 or 20 mol% LiC1 at room temperature on water） gave anti-products with improved enantioselectivities （up to 99% ee） compared to the moderately stereoselective procedure based on prolinamide activation only.

关键词： Aldol reaction amphiphilic prolinamide Lewis acidic metal Co-cayalyst asymmetric catalysis