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国外医学（皮肤性病学分册） 1994年第1期20卷 22-24页

作者： Gropper ca 顾恒

近20年来,超声诊断已在皮肤科推广应用,它提供了一个无创伤性多部位皮肤检查的手段。该文重点复习有关适用于皮肤科的超声技术,叙述有关超声在皮肤科的特殊应用,并讨论了皮肤科超声应用的前景。

关键词：皮肤病超声波诊断

FRACTURE TOUGHNESS OF ORDERED INTERMETALLIC COMPOUNDS FROM SMALL DISKSHAPED SPECIMENS

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中国有色金属学会会刊：英文版 1999年第S1期9卷 106-116页

作者： Alan J.Ardell Department of Materials Science and Engineering, University of california, Los Angeles, ca 90095 1595, U.S.A.

The miniaturized disk bend test(MDBT) can be used to measure the fracture toughness at “infinite" crack length, K ∞, of ordered intermetallic compounds. The specimens tested are disks 3 mm in diameter and typically range in thickness from 250 to 400 μm. A Vickers indentation is impressed within ±10 μm of the center of a metallographically polished disk under a known load, F . The specimen is then subjected to biaxial loading, with the indented side in tension, and tested to failure. In completely brittle intermetallics the fracture stress, σ f, is calculated using a standard formula and measured experimentally as a function of F . When plasticity intervenes prior to fracture it is necessary to calculate the stress using finite element modeling (FEM), the FEM program NIKE2D has been used. Whether or not the specimens deform plastically, the resulting data on σ f vs F are analyzed using established equations of fracture mechanics in conjunction with an empirical rising R curve equation that characterizes the increase in fracture resistance, K R( c ), with crack length, c . Results are presented on several ordered intermetallic compounds. These include Ni 3Ge and Ti 5Si 3, which exhibit no ductility prior to fracture, and NiAl and a complex TiAl alloy, which both exhibit limited ductility before fracturing. The values of K ∞ determined with the MDBT are in very good agreement with values of K IC measured using conventional methods.

关键词： ordered intermetallics Ni 3Ge Ti 5Si 3 TiAl fracture toughness miniature disk bend test

A Study of Synthesis, Immobilization and catalytic capability of Metalloporphyrin

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Chemical Research in Chinese Universities 1998年第2期14卷 3-7页

作者： WANG Xing qiao , GAO Shuang, ca Chang sheng YU Lian xiang, GUO Jing fu, SHUN Shu ju and caO Xi zhang (Department of Chemistry, Jilin University, Changchun, 130023) Jilin Univ Dept Chem Changchun 130023 Peoples R China

A stepwise synthesis method was used to immobilize tetrachloro tetramethyl porphyrins in the supercages of NaCoX molecular sieve. The immobilized porphyrin was characterized by means of UV Vis, IR, DTA, SEM and EPR. A comparision was made for the activities among tetrachloro tetramethyl porphyrins, its cobalt(Ⅱ) complex, NaCoX molecular sieve and the immobilized porphyrin as catalysts in the oxidation reaction of styrene and p cresol. The stability and catalytic capability of the metalloporphyrin is increased after the combination of porphyrin with molecular sieve. In addition, this new type of catalyst tetrachloro tetramethyl porphyrin immobilized in the supercages of NaCoX molecular sieve not only possesses the advantages of both porphyrin and molecular sieve, but also makes up for their respective deficiencies. The experimental results confirmed that both the stability and catalytic capability of metalloporphyrin immobilized in the supercages of molecular sieve are increased.

关键词： Metalloporphyrin Synthesis Immobilization catalytic capability

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分子内结构环境对解离能的影响

高等学校化学学报 2008年第12期29卷 2489-2491页

作者：裘云锋曹泽星厦门大学化学化工学院化学系固体表面物理化学国家重点实验室厦门361005

The density functional calculations were used to explore the dissociation energies of [N(CH3)4]+ and [P(CH3)4]+ and their derivatives from substitution of H for *** results show that the dissociation energies of C—N and C—P bonds gradually increase as the number of hydrogen atoms bonded to N or P increases in the derivatives,showing a remarkable effect of the intramolecular structural environment on the dissociation of the *** dependence of bond dissociation energies on the local structural environment can be ascribed to the hyperconjugation interactions between the C—H bond and lone single electron of N or *** the basis of NBO analyses,the bonding properties of dissociated fragments and their effects on dissociation energies were discussed.

关键词：密度泛函理论解离能自然键轨道(NBO)分析

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九星初雨调蓄池(星北路)设计

城市道桥与防洪 2023年第10期 136-138,145,M0013,M0014页

作者：操宏庆上海市城市建设设计研究总院(集团)有限公司上海市200125

为了进一步控制区域面源污染、降低径流污染,在雨水排水系统建设初雨调蓄池,保证初期雨水不直排河道,实现区域内控污,提高区域水环境质量,对地区生态环境的提升启到了一定的积极作用。以九星初雨调蓄池(星北路)设计为例,通过对常用的重... 详细信息

为了进一步控制区域面源污染、降低径流污染,在雨水排水系统建设初雨调蓄池,保证初期雨水不直排河道,实现区域内控污,提高区域水环境质量,对地区生态环境的提升启到了一定的积极作用。以九星初雨调蓄池(星北路)设计为例,通过对常用的重力流进水模式和水泵提升式进水模式进行比较分析,选取合适的进水模式。结合九星调蓄池(星北路)的选址位置及周边现状状排水管网,对下游受纳水体能力进行复核、运行模式等进行介绍,为类似工程的设计和运行管理提供技术参考。

关键词：初雨调蓄池重力流布置形式放空管

The olfactory circuit of the fruit fly Drosophila melanogaster

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Science China(Life Sciences) 2010年第4期53卷 472-484页

作者： LIANG Liang1,2 & LUO Liqun1 1Howard Hughes Medical Institute, Department of Biology 2Department of Applied Physics, Stanford University, Stanford, ca 94305, USA Howard Hughes Medical Institute Department of Biology Stanford University Stanford USA Department of Applied Physics Stanford University Stanford USA

The olfactory circuit of the fruit fly Drosophila melanogaster has emerged in recent years as an excellent paradigm for studying the principles and mechanisms of information processing in neuronal circuits. We discuss here the organizational principles of the olfactory circuit that make it an attractive model for experimental manipulations, the lessons that have been learned, and future challenges.

关键词： olfactory receptor neurons projection neurons local interneurons antennal lobe mushroom body lateral horn behavior information processing

A new sieve for distinct coordinate counting

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Science China Mathematics 2010年第9期53卷 2351-2362页

作者： LI JiYou1 & WAN DaQing2,1Department of Mathematics,Shanghai Jiao Tong University,Shanghai 200240,China 2Department of Mathematics,University of california,Irvine,ca 92697-3875,USA Department of Mathematics Shanghai Jiao Tong University Shanghai China Department of Mathematics University of California Irvine USA

We present a new sieve for the distinct coordinate counting *** significantly improves the classical inclusion-exclusion sieve for this problem,in the sense that the number of terms is reduced from 2(k 2) to k!,and reduced further to p(k) in the symmetric case,where p(k) denotes the number of partitions of *** an illustration of applications,we give an in-depth study of a basic example arising from coding theory and graph theory.

关键词： sieve distinct coordinate counting

Macroscopic relationship for preferential flow in the vadose zone:Theory and validation

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Science China(Technological Sciences) 2009年第11期52卷 3264-3269页

作者： LIU HuiHai1 & ZHANG RenDuo2 1 Earth Science Division, Lawrence Berkeley National Laboratory, Berkeley, ca 947200, USA 2 School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China Earth Science Division Lawrence Berkeley National Laboratory Berkeley USA School of Environmental Science and Engineering Sun Yat-sen University Guangzhou China

Preferential flow commonly observed in unsaturated soils allows rapid movement of solute from the ground surface or vadose zone to the groundwater, bypassing a significant volume of unsaturated soil and increasing the risk of groundwater contamination. A variety of evidence indicates that complex preferential flow patterns observed from fields are fractals. This paper discusses a macroscopic relationship for modeling preferential flow in the vadose zone. Conceptually, the flow domain can be divided into active and inactive regions. Flow occurs preferentially in the active region (characterized by fractals), and inactive region is simply bypassed. The portion of the active region was found to be a power function of saturation. The validity of this macroscopic relationship is demonstrated by its consistency with field observations and the related numerical experiments.

关键词： preferential flow constitutive relations vadose zone hydrology

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微缩丽江古城

中国特色新型档案智库:类型、特点与建设路径

大众汽车（汽车旅行） 2014年第1期 112-119页

作者： ca

八百多年历史的丽江古城，以雪山、古屋、古树、小桥、流水等独特的水乡景致，多彩多姿的民族文化成为世界知名的旅游胜地。这里的一花、一草、一木，任何一物都有着“曲径通幽处，禅房花木深”的禅意与美境。身处其中，只能通过感官上... 详细信息

八百多年历史的丽江古城，以雪山、古屋、古树、小桥、流水等独特的水乡景致，多彩多姿的民族文化成为世界知名的旅游胜地。这里的一花、一草、一木，任何一物都有着“曲径通幽处，禅房花木深”的禅意与美境。身处其中，只能通过感官上的接触，抑或看，抑或听，而多半是心灵上的感知，能觉到其中的美妙。有人说，丽江古城过于商业化，已经失去了本真，而事实上，在繁花似锦的商业包装的外壳下，她依旧有着耐人寻味，值得去深究的细节。

关键词：丽江古城商业包装民族文化商业化雪山外壳水乡美境旅游历史花木古屋古树感知感官多彩禅意

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档案学刊 2022年第1期 1-6,25页

作者：徐拥军嘎拉森中国人民大学信息资源管理学院北京100872 中国人民大学档案事业发展研究中心北京100872

“十四五”时期加强中国特色新型档案智库建设具有重要意义。根据建设主体、职能定位的不同,可将中国特色新型档案智库分为以综合档案馆为建设主体的档案内容研究类智库和以开设档案学专业的高校为建设主体的档案业务研究类智库两大类... 详细信息

“十四五”时期加强中国特色新型档案智库建设具有重要意义。根据建设主体、职能定位的不同,可将中国特色新型档案智库分为以综合档案馆为建设主体的档案内容研究类智库和以开设档案学专业的高校为建设主体的档案业务研究类智库两大类型。两类档案智库的依托主体、职能定位、服务对象、研究内容、研究方法、服务产品、工作要求各有特点、各具优劣。应该加强统筹规划,分层分类推进档案智库建设;健全管理机制,科学规范开展档案智库建设;促进交流合作,实现优势互补协同共建。

关键词：新型智库档案事业智库建设