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Structural and Electronic Properties of Ruthenium-Doped Germanium Clusters

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Structural and Electronic Properties of Ruthenium-Doped Germ...

Prediction of Stable Ruthenium Silicides from First-Principles Calculations: Stoichiometries, Crystal Structures, and Physical Properties

第六届全国计算原子与分子物理学术会议

作者： Yuanyuan Jin Yonghong Tian xiaoyu kuang Cheng Lu Jose? Luis Cabellos Sukanta Mondal Gabriel Merino Institute of Atomic and Molecular Physics Sichuan University Department of Physics Nanyang Normal University Department of Physics and Optoelectronic Engineering Yangtze University Department of Physics and High Pressure Science and Engineering Center University of Nevada

＜正＞During the past decade,there has been tremendous interest in germanium-based clusters because they are the building blocks of self-assembling semiconductors and are useful in synthesizing new novel materials.[1,2]A large number of experimental and theoretical investigations have been performed on pure germanium clusters.[3,4]According to these studies,such clusters cannot form stable fullerene-like ***,

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Prediction of Stable Ruthenium Silicides from First-Principl...

Insights into the geometries, electronic and magnetic properties of neutral and charged palladium clusters

第六届全国计算原子与分子物理学术会议

作者： Chuanzhao Zhang xiaoyu kuang Yuanyuan Jin Cheng Lu Dawei Zhou Peifang Li Gang Bao Andreas Hermann Institute of Atomic and Molecular Physics Sichuan University Department of Physics Nanyang Normal University Beijing Computational Science Research Center College of Physics and Electronic Information Inner Mongolia University for the Nationalities

We present results of an unbiased structure search for stable ruthenium silicide compounds with various stoichiometries, using a recently developed technique that combines particle swarm optimization algorithms with first-principles calculations. Two experimentally observed structures of ruthenium silicides, Ru Si(space group P23) and RuSi(space group Pbcn), are successfully reproduced under ambient pressure conditions. In addition, a stable Ru Si compound with β-Fe Si structure type(space group Cmca) was found. The calculations of the formation enthalpy, elastic constants, and phonon dispersions demonstrate the CmcaRu Si compound is energetically, mechanically, and dynamically stable. The analysis of electronic band structures and densities of state reveals that the Cmca-Ru Si phase is a semiconductor with a direct band gap of 0.480 e V and is stabilized by strong covalent bonding between Ru and neighboring Si atoms. On the basis of the Mulliken overlap population analysis, the Vickers hardness of the Cmca structure Ru Si is estimated to be 28.0 GPa, indicating its ultra-incompressible nature.

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Insights into the geometries, electronic and magnetic proper...

第六届全国计算原子与分子物理学术会议

作者： Xiaodong Xing Andreas Hermann xiaoyu kuang Meng Ju Cheng Lu Yuanyuan Jin Xinxin Xia George Maroulis Institute of Atomic and Molecular Physics Sichuan University Department of Physics Nanyang Normal University Beijing Computational Science Research Center Department of Chemistry University of Patras

We performed an unbiased structure search for low-lying energetic minima of neutral and charged palladium Pd(n = 2-20, Q = 0, +1 and –1) clusters using CALYPSO method in combination with density functional theory(DFT) calculations. The main candidates for the lowest energy neutral, cationic and anionic clusters are identified, and several new candidate structures for the cationic and anionic ground states are obtained. It is found that the ground state structures of small palladium clusters are more sensitive to the charge states. For the medium size Pd(n = 16-20) clusters, a fcc-like growth behavior is found. The structural transition from bilayer-like structures to cage-like structures is likely to occur at n = 14 for the neutral and cationic clusters. In contrast, for the anionic counterparts, the structural transition occurs at Pd. The photoelectron spectra(PES) of palladium clusters are simulated based on the time-dependent density functional theory(TD-DFT) method and compared with the experimental data. The good agreement between the experimental PES and simulated spectra provides us unequivocal structural information to fully solve the global minimum structures, allowing for new molecular insights into the chemical interactions in the Pd cages.

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不动产统一测绘的可行性探究与展望

北京测绘 2017年第3期31卷 12-16页

作者：闫岩贾艳匡晓宇孟凡影北京市土地权籍事务中心北京110103 北京帝测科技股份有限公司北京100012

随着《不动产登记暂行条例》的出台,与之相关的不动产测绘行业现状成为多方关注的焦点。统一登记背景下,不动产测绘行业面临的挑战和亟待解决的问题同样值得深入思考和分析。本文在收集土地、海域以及房屋、林木、草地等定着物现行测绘... 详细信息

随着《不动产登记暂行条例》的出台,与之相关的不动产测绘行业现状成为多方关注的焦点。统一登记背景下,不动产测绘行业面临的挑战和亟待解决的问题同样值得深入思考和分析。本文在收集土地、海域以及房屋、林木、草地等定着物现行测绘标准(规定)并进行实地调研的基础上,全面阐述了我国各种不动产测绘现状,并就统一登记背景下不动产测绘工作面临的困难和发展的方向进行了系统分析。

关键词：不动产测绘现状研究需求分析

超高强度不锈钢10Cr13Co13Mo5Ni3W1VE微观组织对局部腐蚀行为的影响

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材料工程 2024年第5期52卷 103-116页

作者：滕鹏钟锦岩匡效禹赵振江张淑琦蔡嘉辉李松梅刘建华于美钟平北京航空航天大学材料科学与工程学院北京100191 中国航发北京航空材料研究院钢与稀贵金属所北京100095

采用未时效、200、400℃以及500℃时效状态下10Cr13Co13Mo5Ni3W1VE(S280)马氏体超高强度不锈钢为研究对象,通过X射线衍射(XRD)、透射电子显微镜(TEM)、背散射电子衍射(EBSD)等测试方法,结合电化学测试手段与X射线光电子能谱仪(XPS)测试... 详细信息

采用未时效、200、400℃以及500℃时效状态下10Cr13Co13Mo5Ni3W1VE(S280)马氏体超高强度不锈钢为研究对象,通过X射线衍射(XRD)、透射电子显微镜(TEM)、背散射电子衍射(EBSD)等测试方法,结合电化学测试手段与X射线光电子能谱仪(XPS)测试,分析S280的微观组织结构特征演变与钝化膜结构成分与耐蚀性能,研究钝化膜稳定性特征与材料微观组织结构的关系。结果表明:500℃时效温度下的S280钢有细小弥散的富含Cr,Mo元素的析出相,分布在马氏体板条中。随着时效温度升高,无明显的残余奥氏体及逆转变奥氏体析出。在成膜电位(0.1~0.85 V)下,S280钝化膜在pH=8.5的硼酸盐缓冲液中呈p型半导体性质,表现为双层膜结构,外部由疏松多孔的Fe/Cr氢氧化物组成,内层由致密的Cr/Fe氧化物构成,其成分主要是Cr_(2)O_(3)。通过电化学阻抗测试结合Mott-Schottky分析,探明S280在200℃时效下耐蚀性最好,其耐蚀性能由晶界取向特性与沉淀相导致的元素偏析共同影响。

关键词：超高强度不锈钢S280 微观组织钝化膜局部腐蚀

维普期刊数据库博看期刊

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蒙药山野豌豆多糖的提取与含量测定

中国药房 2017年第4期28卷 518-521页

作者：李振云学英于海青李成林郭晓宇况媛媛内蒙古医科大学药学院呼和浩特010110

目的:优化蒙药山野豌豆多糖提取液经活性炭脱色的条件,并建立其提取及含量测定方法。方法:以水提醇沉法提取蒙药山野豌豆粗多糖。以脱色率为考察指标,设计正交试验,考察活性炭用量、脱色时间及脱色温度对粗多糖脱色的影响,优化活性炭脱... 详细信息

目的:优化蒙药山野豌豆多糖提取液经活性炭脱色的条件,并建立其提取及含量测定方法。方法:以水提醇沉法提取蒙药山野豌豆粗多糖。以脱色率为考察指标,设计正交试验,考察活性炭用量、脱色时间及脱色温度对粗多糖脱色的影响,优化活性炭脱色条件。以葡萄糖为对照品,采用苯酚-硫酸法,490 nm波长下经紫外分光光度法测定粗多糖中多糖含量。结果:优化的活性炭脱色条件为活性炭用量3%、脱色时间40 min、脱色温度60℃。以此条件对粗多糖进行脱色验证试验,平均脱色率可达19.77%(RSD=1.85%,n=3)。蒙药山野豌豆粗多糖平均提取得率为4.56%(RSD=2.38%,n=3),提取液中多糖含量为1.98%(RSD=2.18%,n=4)。结论:本试验提取多糖得率重复性较好;建立的多糖含量测定方法稳定、可行。

关键词：蒙药山野豌豆多糖分光光度法含量测定活性炭脱色率正交试验

基于元素组学的黔北麻羊羊腿肉的产地溯源可行性研究

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食品与发酵工业 2024年第22期50卷 204-213页

作者：张孝红袁付明周绍均况晓宇方鑫碧何艳梅邓勇张建永遵义医科大学药学院贵州遵义563000 遵义市产品质量检验检测院贵州遵义563000

基于元素组学分析黔北麻羊羊腿肉中的元素组成及含量,并与我国四大羊肉主产区对比分析,结合化学计量法进行产地溯源可行性研究。收集我国贵州、内蒙古、宁夏、新疆和甘肃5个产区的羊前腿肉共65份,采用微波消解法预处理后,通过电感耦合... 详细信息

基于元素组学分析黔北麻羊羊腿肉中的元素组成及含量,并与我国四大羊肉主产区对比分析,结合化学计量法进行产地溯源可行性研究。收集我国贵州、内蒙古、宁夏、新疆和甘肃5个产区的羊前腿肉共65份,采用微波消解法预处理后,通过电感耦合等离子体质谱法和电感耦合等离子体发射光谱法检测羊腿肉中17种元素的含量,结合单因素方差分析、主成分分析和正交偏最小二乘法判别分析对黔北麻羊进行产地区分,基于差异元素建立黔北麻羊产地判别模型。黔北麻羊与其余4个产区之间存在8种差异元素Mg、Al、K、Fe、P、Rb、Cr、Sn,建立了Fisher判别模型,对黔北麻羊的判别正确率为95%,采用“留一法”交叉验证对黔北麻羊的判别正确率为95%。通过8种差异元素建立的判别模型对黔北麻羊进行有效区分,元素组学可为黔北麻羊溯源分析提供新的参考。

关键词：羊肉元素组学黔北麻羊产地溯源化学计量法

Urban expansion and intra-urban land evolution as well as their natural environmental constraints in arid/semiarid regions of China from 2000–2018

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Journal of Geographical Sciences 2023年第7期33卷 1419-1441页

作者： PAN Tao kuang Wenhui SHAO Hua ZHANG Chi WANG xiaoyu WANG Xinqing School of Geography and Tourism Qufu Normal UniversityRizhao 276826ShandongChina Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyCASUrumqi 830011China Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection College of Resources and EnvironmentLinyi UniversityLinyi 276000ShandongChina

Rapid urbanization has occurred in arid/semiarid China,threatening the sustainability of fragile dryland ecosystems;however,our knowledge of natural environmental constraints on multiscale urban lands in this region is still *** solve this issue,this study retrieved 15-m multiscale urban *** indicated that urban area increased by 68%during 2000–2018,and one-third of the increase was contributed by only three large *** coverage of impervious surface area(ISA) and vegetated area(VA) increased by 16.6%and 1.38%,*** land-cover change may be helpful in suppressing wind erosion and sand *** also found that the newly urban lands had relatively lower ISA and higher VA than the old urban lands,indicating an improved human settlement *** environmental constraints on urban expansion were identified,with cities in oasis urban environments(OUEs) that had water supply expanding 150% faster than cities in desert urban environments(DUEs).Urban development was also constrained by terrain,with 73% of the ISA expansion occurring in relatively flat ***,the aggregated pattern of urbanization and the increase in ISA and VA in the newly urbanized lands have improved water-use efficiency and ecological services and benefited desert ecosystem protection in arid/semiarid China.

关键词： urbanization natural environmental constraints pixel and subpixel land change arid and semiarid regions of China

Bond Mechanical Properties of Glass Fiber Reinforced Polymer Anti-Floating Anchor in Concrete Baseplate

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Journal of Shanghai Jiaotong university(Science) 2021年第6期26卷 804-812页

作者： BAI xiaoyu ZHENG Chen ZHANG Mingyi LIU Xueying kuang Zheng School of Civil Engineering Qingdao University of TechnologyQingdao 266033ShandongChina Cooperative Innovation Center of Engineering Construction and Safety in Shandong Blue Economic Zone Qingdao 266033ShandongChina

Combined with fiber Bragg grating(FBG)sensing technology,four glass fiber reinforced polymer(GFRP)anti-floating anchors and four steel anti-floating anchors were tested for on-site destructive failure to investigate the anchoring performance and the bonding characteristics between GFRP anti-floating anchor and concrete *** test results show that bending GFRP anchor will be broken at the common boundary between vertical anchorage section and bending section during the pullout process,and the spring-back load provided by the rupture contributes to a decrease of bearing capacity and an inflection point on the load-slip *** loaddisplacement curve of the straight anchor GFRP anti-floating anchor is smoother and has better predictability than the same type of steel ***,different forms of GFRP anti-floating bolt have different bondslip constitutive *** introducing the sliding-slip correction factor of bending bolt,constitutive models describing the rising-section of sliding-slip relation of bending and straight-anchored GFRP anti-floating bolt are established *** model can fit the test results rightly.

关键词： glass fiber reinforced polymer(GFRP) anti-floating anchor bolt axial force bearing capacity loadslip constitutive relationship