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半刚接钢框架内填实体RC墙结构的地震易损性能评估

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西安建筑科技大学学报（自然科学版） 2024年第1期56卷 38-46页

作者：孙国华李坤明胡月华黎明苏州科技大学江苏省结构工程重点实验室江苏苏州215011 苏州科技大学土木工程学院江苏苏州215011

为评估半刚接钢框架内填实体RC墙结构(PSRCW)的地震易损性能及倒塌储备能力,考虑层数和抗震设防烈度影响合理设计了4个PSRCW结构基准算例,采用Latin超立方抽样方法考虑型钢、混凝土、钢筋等材料力学性能及内填RC墙体厚度几何尺寸的随机... 详细信息

为评估半刚接钢框架内填实体RC墙结构(PSRCW)的地震易损性能及倒塌储备能力,考虑层数和抗震设防烈度影响合理设计了4个PSRCW结构基准算例,采用Latin超立方抽样方法考虑型钢、混凝土、钢筋等材料力学性能及内填RC墙体厚度几何尺寸的随机性,拓展为4组共计160个PSRCW算例.通过合理选取40条汶川地区实测地震记录,与每组40个PSRCW结构样本随机组合,构成了4组40个地震-结构样本对,通过弹塑性时程分析方法确定了PSRCW结构在“弹性极限”“完全运行”“运行”“生命安全”“接近倒塌”“倒塌”性态下的地震易损性曲线,并进行了抗震性能评估,量化了PSRCW结构的倒塌储备能力.分析结果表明:PSRCW结构的倒塌安全储备系数在3.0~4.3之间,具有良好的抗地震倒塌能力.

关键词：钢框架内填墙易损性倒塌安全储备系数

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某地羊脂黑曜岩的岩石矿物学特征

矿物学报 2024年第1期44卷 65-72页

作者：李珊席佳鑫曾庆进王辅亚李坤明魏景明中国科学院广州地球化学研究所广东广州510640 中国科学院大学北京100049 广东省矿物物理与材料研究开发重点实验室广东广州510640 广州市水筵轩商贸有限公司广东广州510370

采用微区X射线衍射(μXRD)、X射线荧光光谱(XRF)、电感耦合等离子体质谱仪(ICP-MS)、扫描电子显微镜(SEM)和显微红外光谱(Miro-FTIR)等岩石矿物学分析测试手段,对某一地区的羊脂黑曜岩的物相组成、显微结构和化学成分等进行了系统研究... 详细信息

采用微区X射线衍射(μXRD)、X射线荧光光谱(XRF)、电感耦合等离子体质谱仪(ICP-MS)、扫描电子显微镜(SEM)和显微红外光谱(Miro-FTIR)等岩石矿物学分析测试手段,对某一地区的羊脂黑曜岩的物相组成、显微结构和化学成分等进行了系统研究。结果表明,该羊脂黑曜岩的基本组成特征与其他2个产地的黑曜岩类似,其化学组成都以SiO_(2)、Al_(2)O_(3)、K_(2)O、Na_(2)O为主,属于流纹岩化学成分范围。宏观上表现为非晶质熔体,但熔体内存在微米-亚微米粒径的细小矿物,以羊脂黑曜岩所含微纳米粒径矿物最为丰富。其中所含的钾霞石、磁赤铁矿和黄铁矿都是具有特殊化学性质的矿物,这可能是羊脂黑曜岩的物理化学性质明显优于其他2类黑曜岩的原因。

关键词：黑曜岩纳米矿物钾霞石磁赤铁矿

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云南梨地方品种果实表型性状多样性分析

果树学报 2024年第1期41卷 41-51页

作者：梁艳萍董菲黄文静陈瑶丁仁展李坤明云南省农业科学院园艺作物研究所昆明650205 普洱学院茶叶咖啡学院云南普洱665000

【目的】深入了解云南梨地方品种果实表型性状的变异特点和多样性。【方法】以云南有代表性的61个梨地方品种为试验材料,对果实16个描述型性状和7个数量型性状进行变异类型和多样性分析,利用电子鼻技术检测果实香气并进行主成分分析。... 详细信息

【目的】深入了解云南梨地方品种果实表型性状的变异特点和多样性。【方法】以云南有代表性的61个梨地方品种为试验材料,对果实16个描述型性状和7个数量型性状进行变异类型和多样性分析,利用电子鼻技术检测果实香气并进行主成分分析。【结果】云南梨地方品种果实的16个描述型性状变异类型丰富,其中果实形状和果实成熟期的变异类型最多。各描述型性状的多样性指数(H’)在0.45~1.88之间。19个梨地方品种果实在成熟时果皮分别着鲜红、淡红、粉红、暗红等不同盖色。7个数量型性状变异系数在11.25%~61.79%之间,单果质量的变异系数最高;多样性指数(H’)为1.676~2.080,果实纵径、果柄长度、可溶性固形物含量、果实横径、果形指数的多样性指数均大于2.0。电子鼻技术可以区分供试地方品种,WIW(硫化氢类)、W5S(氮氧化物)、W2W(芳香成分和有机硫化物)等3个传感器在模式识别中起主要作用。【结论】云南梨地方品种果实描述型性状变异类型丰富,数量型性状多样性指数较高。筛选出会泽火瓢梨等7个果皮着鲜红色的品种可作为红色梨选育的优异资源。电子鼻技术可以区分61个云南梨地方品种,可用作地方品种鉴定的辅助手段。

关键词：梨云南地方品种果实性状多样性电子鼻

MICROSTRUCTURE AND EXTENDED SOliD SOLUBIliTY OF Tb IN RAPIDLY SOliDIFIED Ag-Tb ALLOY

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Acta Metallurgica Sinica(English Letters) 1991年第8期4卷 143-146页

作者： NING Yuantao ZHO U Xinming li Yongnian kunming Institute of Precious Metals,kunming,China Kumming Inst of Precious Metals Kumming China

The 0,05—0.08 mm thick splat foils of Ag-Tb alloy,containing Tb up to 10 at.-%,were made by the hammer-anvil *** cooling rate was in order of 10~6 K/*** metastable extension of solid solubility of Tb in the alloy was measured to be up to 5 at.-% by lattice parameter *** secondary phase in metastable eutectic structure was identi- fied as Ag_3Tb from diffraction *** microstructure and micro-defect in as-quenched Ag-Tb splat foil were also observed.

关键词： rapid solidification Ag-Tb alloy solid solubility

Phylogenetic studies of the core Alismatales inferred from morphology and rbcL sequences

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Progress in Natural Science:Materials International 2009年第8期19卷 931-945页

作者： Xiaoxian li, Zhekun Zhou kunming Institute of Botany, Chinese Academy of Sciences, kunming 650204, China kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China

The phylogeny of Alismatales remains an area of deep uncertainty, with different arrangements being found in studies that examined various subsets of genes and taxa. Herein we conducted separate and combined analyses of 103 morphological characters and 52 rbcL sequences to explore the controversial phylogenies of the families. Congruence between the two data sets was explored by computing several indices. Morphological data sets contain poor phylogenetic signals. The homology of morphological characters was tested based on the total evidence of phylogeny. The incongruence between DNA and morphological results; the hypothesis of the ‘Cymodoceaceae complex’; the relationships between Najadaceae and Hydrocharitaceae; the intergeneric relationships of Hydrocharitaceae; and the evo- lutionary convergence of morphological characters were analyzed and discussed.

关键词： Alismatales Morphological phylogeny rbcL sequences Cymodoceaceae complex Najadaceae Hydrocharitaceae

云南野生猕猴桃资源不同居群遗传多样性及遗传演化关系

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中国南方果树 2024年第2期53卷 152-158页

作者：王连润万红陶磅陈霞李坤明沙毓沧云南省农业科学院园艺作物研究所昆明650205

应用SSR分子标记研究云南10个地理居群野生猕猴桃的遗传多样性及遗传演化关系。结果表明,不同地理居群间的遗传多样性水平差异不大;居群间的遗传一致度在0.9899~0.9991之间,遗传分化系数(Gst)在0.0011~0.1743之间。威信居群与彝良居群... 详细信息

应用SSR分子标记研究云南10个地理居群野生猕猴桃的遗传多样性及遗传演化关系。结果表明,不同地理居群间的遗传多样性水平差异不大;居群间的遗传一致度在0.9899~0.9991之间,遗传分化系数(Gst)在0.0011~0.1743之间。威信居群与彝良居群间的遗传一致度最高,遗传距离最小,亲缘关系最近;永善居群与云龙居群间的遗传一致度最低,遗传距离最大,亲缘关系最远。10个居群可分为两大类群,师宗、绥江、西畴和永善4个居群聚为类群Ⅰ,麻栗坡、屏边、云龙、镇雄、彝良和威信6个居群聚为类群Ⅱ。类群Ⅰ内的遗传演化关系可分为2个进化层次,师宗居群与绥江居群之间以及西畴居群与永善居群之间的遗传进化关系最近。类群Ⅱ内的遗传演化关系可分为5个进化层次,麻栗坡居群与屏边居群之间的遗传进化关系最近,云龙居群与威信居群之间的亲缘关系较远。研究结果可为加快云南猕猴桃属种质资源的研究利用提供参考。

关键词：云南野生猕猴桃 SSR 遗传多样性遗传演化

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Construction of NiCo_(2)O_(4) nanoflake arrays on cellulose-derived carbon nanofibers as a freestanding electrode for high-performance supercapacitors

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Frontiers of Chemical Science and Engineering 2023年第6期17卷 691-703页

作者： Xuepeng Ni kunming li Changlei li Qianqian Wu Chenglin liu Huifang Chen Qilin Wu Anqi Ju College of Materials Science and Engineering&State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Donghua UniversityShanghai 201620China Key Laboratory of High-Performance Fibers&Products Ministry of EducationDonghua UniversityShanghai 201620China Weifang Xinlong Biomaterial Co. Ltd.Weifang 261000China

Cellulose has a wide range of applications in many fields due to their naturally degradable and low-cost characteristics,but few studies can achieve cellulose-nanofibers by conventional ***,we demonstrate that the freestanding cellulose-based carbon nanofibers are successfully obtained by a special design of electrospinning firstly,pre-oxidation and high-temperature carbonization(1600℃),which display a superior electrical conductivity of 31.2 S·cm^(-1)and larger specific surface area of 35.61 m^(2)·g^(-1)than that of the polyacrylonitrile-based carbon nanofibers(electrical conductivity of 18.5 S·cm^(-1),specific surface area of 12 m^(2)·g^(-1).The NiCo_(2)O_(4)nanoflake arrays are grown uniformly on the cellulose-based carbon nanofibers successfully by a facile one-step solvothermal and calcination *** as-prepared cellulose-based carbon nanofibers/NiCo_(2)O_(4)nanoflake arrays are directly used as electrodes to achieve a high specific capacitance of 1010 F·g^(-1)at 1 A·g^(-1)and a good cycling stability with 90.84%capacitance retention after 3000 times at 10 A·g^(-1).Furthermore,the all-solid-state symmetric supercapacitors assembled from the cellulose-based carbon nanofibers/NiCo_(2)O_(4)deliver a high energy density of 62 W·h·kg(-1) at a power density of 1200 W·kg^(-1).Six all-solid-state symmetric supercapacitors in series can also power a‘DHU’logo consisted of 36 light emitting diodes,confirming that the cellulose-based carbon nanofiber is a promising carbon matrix material for energy storage devices.

关键词： cellulose carbon nanofibers NiCo_(2)O_(4) supercapacitors

XO(X=Ti,Mn)decorated hollow multi-channel carbon sub-micro fiber networks as freestanding cathode for lieS batteries

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Journal of Materiomics 2023年第1期9卷 215-222页

作者： Qianqian Wu Tianbao Yan kunming li Xuepeng Ni Fanlong Zeng Anqi Ju State Key Laboratory for Modification of Chemical Fibers and Polymer Materials&College of Materials Science and Engineering Donghua UniversityShanghai201620China Center for Civil Aviation Composites&Shanghai Collaborative Innovation Center of High-Performance Fibers and Composites(Province-Minitry Joint) Donghua UniversityShanghai201620China

lithium-sulfur(lisingle bondS)batteries are considered as one of the most promising high-energy storage devices due to the high theoretical capacity(1675 mA·h·g^(-1))and large energy density(2600 W·h·kg^(-1)).However,the poor conductivity of sulfur and“shuttle effect”of soluble polysulfide intermediates limit practical applications of lisingle bondS ***,four kinds of carbon sub-micro fibers with different structures were designed and prepared,the effect of structure on lisingle bondS battery was *** this basis,the XO(X=Ti,Mn)decorated hollow multi-channel carbon sub-micro carbon fibers(HMCMFs)were prepared by electrospinning and *** HMCMFs can not only supply nanopores for relieving the expansion of sulfur but also served as high conductivity freestanding substrate for sulfur loading,meanwhile the decorated XO(X=Ti,Mn)can provide powerful chemical adsorption to polysulfide intermediates and limit“shuttle effect”Therefore,the TiO-HMCMFs/S composite shows high specific capacity of 900 mA·h·g^(-1)and maintain stable specific capacities up to∼600 mA·h·g^(-1)over 300 cycles at 0.1 A·g^(-1).This work offers a facile method to build efficient sulfur cathode to acquire lisingle bondS batteries with high performance.

关键词： lithium-sulfur batteries TiO MnO Carbon sub-miacro fibers

A DISCUSSION ON BIOGEOGRAPHICAL liNES OF THE TROPICAL SUBTROPICAL YUNNAN

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Chinese Geographical Science 2002年第1期12卷 91-97页

作者： ZHU Hua, YAN li chun(kunming Division of Xishuangbanna Tropical Botanical Garden, the Chinese Academy of Sciences, kunming 650223, P.R.China) kunming Division of Xishuangbanna Tropical Botanical Garden the Chinese Academy of Sciences Kunming P. R. China

Based on comparative studies on four regional floras from northwest, west, south and southeast of Yunnan respectively, the formerly suggested two biogeographical lines, i.e. the “Tanaka line" and the “Ecogeographical Diagonal line", both going from northwest to southeast of Yunnan, and their significance are discussed. In family and generic levels, similarity coefficients among the four compared floras are more than 93% and 60% separately, which indicate the close floristic affinities among them. The highest similarity coefficient, i.e. 98.7% in family level and 78.6% in generic level separately, is found between the regional flora of northwest Yunnan and the flora of southeast Yunnan although these two regions are the most distant away each other among the compared regional floras. The flora of northwest Yunnan is also the most similar to the flora of southeast Yunnan in floristic composition. These support the idea of “Ecogeographical Diagonal line". In specific level, the relatively high similarity coefficient is between the regional flora of west Yunnan and the one of south Yunnan. The floristic affinities among these regional floras and some distribution patterns could be explained by the geological history and tectonic theory of Yunnan.

关键词： biogeographical lines floristic affinity Yunnan