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非磁性小粒子散射的磁偶极贡献

微波学报 2002年第2期18卷 39-44页

作者：梁子长米君复旦大学波散射和遥感中心复旦大学物理系上海200433

采用磁偶极子和电四极子模型下的静场近似方法 ,得到了球形小粒子电磁散射场的两个高阶项 ,其大小正比于粒子半径的五次方 ,它和Mie级数解中对应的两项近似结果完全一致 ,从而可以将Mie级数解中这两项解释为磁偶极和电四极项散射的贡献... 详细信息

采用磁偶极子和电四极子模型下的静场近似方法 ,得到了球形小粒子电磁散射场的两个高阶项 ,其大小正比于粒子半径的五次方 ,它和Mie级数解中对应的两项近似结果完全一致 ,从而可以将Mie级数解中这两项解释为磁偶极和电四极项散射的贡献。该方法仅要求粒子的几何尺寸的平方远小于波长的平方 ,在该条件下可将这种方法推广应用到非球形粒子 ,并给出了椭球和矩形两种非球形小粒子磁偶极散射贡献的理论计算公式 ,其结果与FDTD数值模拟结果有很好的一致性。

关键词：电偶极,磁偶极,电四极,静场近似

Melt-spun Al_(70-X)Si_(30)Mn_X (X=0,3,5,7,10) anode in lithium-ion batteries

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Science China(Technological Sciences) 2009年第8期52卷 2288-2294页

作者： SUN ZhanBo1, LI XuePeng1, WANG XiaoDong1, HU Qing1, ZHAO MingShu1, ZHU YaoMin2. LI Yan2.& SONG XiaoPing1 1 School of Science, State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an 710049, China 2.School of Materials Science and Engineering, Henan University of Science and Technology, Luoyang 471003, China 1. School of Science State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong University Xi’an 710049 China 2. School of Materials Science and Engineering Henan University of Science and Technology Luoyang 471003 China

Al70-XSi30MnX (X=0, 3, 5, 7, 10, mol%) ribbons were prepared by melt spinning. A supersaturated solid solution of Si and Mn in fcc Al and some microstructures consisting of nano grains were obtained. Some alloys with nano-sized grains exhibited high discharge capacities and favorable cycle properties. The capacity of more than 400 mAh/g could be obtained in melt-spun Al67Si30Mn3 alloy after 2. cycles and more than 300 mAh/g after 40 cycles. Li/Si and Li/Al compounds in the anodes of pure Al and pure Si were not detected in Al-Si-Mn alloys inserted by Li. It is considered that the formation of the supersaturated solid solution and refinement of microstructures have prevented the alloys from the forming the compounds with superfluous Li. As a result, the electrochemical properties have been improved.

关键词： Al-Si-Mn alloy melt spinning microstructure electrochemical property

CENOZOIC LARGE-SCALE STRIKE-SLIP FAULT IN WEST YUNNAN, CHINA

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地学前缘 2000年第S1期7卷 268-269页

作者： Ji Jianqing 1, Zhong Dalai 2. Sang Haiqing 2. Zhang Liansheng 2.WT5,5”BX](1 Department of Geology, Peking University, Beijing 100871,China 2.Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002.,China)

During the collision between India and Eurasia, the continental compression and shorten is thought to be absorbed by the way of thickening of the Tibetan plateau crust and strike\|slip extrusion outwardly of blocks surrounding the Tibetan plateau. A series of models have been proposed recently, of which the most typical one is continental blocks extrusion by Tapponnier et al.. Virtually previous studies show that the Red River—Ailaoshan fault is the eastern boundary of extrusion Indochina displaced southward relative to South China about 2. Ma ago, and more, the western boundary of extrusion blocks is inferred to be Sijie fault in the eastern Burma. But the movement age of Sijie fault is around 13 Ma inferred from the age of Andeman Sea formation and different from that of the Red River—Ailaoshan fault. It is an important scientific problem where the western boundary of extrusion blocks is.

关键词： the western boundary of extrusion blocks Cenozoic dextral strike\|slip fault deformation age West Yunnan

A Study on Drawing the Shadow of a Curve Revolving Object under Commonly Used Ray

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Computer Aided Drafting,Design and Manufacturing 2008年第2期18卷 113-116页

作者： YU Xi-fa1, YI Su-jun2. SUN Huai-lin1 (1. College of Civil Science and Engineering, Yangzhou University, Yangzhou 2.5009 2. Mathematics and Information College, East China Institute University, Fuzhou 344000, China)

The shadow of a circle casting on a unparallel plane is an ellipse, the shadow algorithm involves a perspective affine transformation. Under commonly used light, the transformation matrix for parallel circles of different diameters casting shadows onto the same plane is identical. Using AutoCAD to get the shadow of a general object of revolution, it only needs to take a series of circles along the axis of symmetry and get their corresponding shadows of ellipses, drawing an envelope to cover all these silhouettes results in the required overall shadow. Then the discrete points of shadow contour line are projected back onto the original object surface, shadow on the object is obtained altogether.

关键词： engineering graphics shadow algorithm curve object of revolving ellipse envelope

A possible proton pygmy resonance in ^(17)Ne

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Science China(Physics,Mechanics & Astronomy) 2011年第S1期54卷 49-52页

作者： MA ZhongYu1,2.& TIAN Yuan1 1 China Institute of Atomic Energy, Beijing 102.13, China 2.Center of Theoretical Nuclear Physics, National Laboratory of Heavy Collision, Lanzhou 730000, China 1. China Institute of Atomic Energy Beijing 102413 China2. Center of Theoretical Nuclear Physics National Laboratory of Heavy Collision Lanzhou 730000 China

The low-lying electric dipole strengths in proton-rich nuclei 17F and 17Ne, which can be produced at HIRFL-CSR in Lanzhou, are investigated. In the framework of the covariant density functional theory the self-consistent relativistic Hartree Bogoliubov model and the relativistic quasiparticle random phase approximation with the NL3 parameter set and Gogny pairing interaction are adopted in the calculations. A pronounced dipole peak appears below 10 MeV in17Ne, but does not occur in 17F. The prop erties of this low-lying E1 excitation in 17Ne are studied, which may correspond to a proton pygmy resonance with different characteristics from those of giant dipole resonance.

关键词： proton pygmy resonance relativistic Hartree-Bogoliubov model relativistic quasiparticle random phase approximation

黔东南凯里-榕江-从江前寒武系甚低级变质作用研究

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岩石学报 2018年第3期34卷 669-684页

作者：安佳丽王河锦苑蕾造山带与地壳演化教育部重点实验室北京100871 北京大学地球与空间科学学院北京100871

根据碎屑岩甚低级变质作用原理,运用伊利石结晶度、绿泥石结晶度、伊利石-白云母多型、伊利石(白云母)b_0值、绿泥石温度计等碎屑岩低温变质研究的方法,分析研究了黔东南前寒武系67个<2.m的粘土样品,得到黔东南凯里-榕江-从江一带下江... 详细信息

根据碎屑岩甚低级变质作用原理,运用伊利石结晶度、绿泥石结晶度、伊利石-白云母多型、伊利石(白云母)b_0值、绿泥石温度计等碎屑岩低温变质研究的方法,分析研究了黔东南前寒武系67个2.m的粘土样品,得到黔东南凯里-榕江-从江一带下江群伊利石结晶度为0.2.1~0.607°Δ2.Cu Kα、绿泥石结晶度为0.2.9~1.393°Δ2.Cu Kα,变质带伊利石-白云母多型均为2._1型,伊利石(白云母)b_0值为0.9001~0.9048nm,平均0.902.nm。根据伊利石(白云母)b_0值的累积频率曲线得出研究区下江群遭受的变质作用为典型的中压变质类型。由Cathelineau(1988)绿泥石温度计估算出下江群浅变质带峰期变质温度为362.382.。以上结果表明凯里-榕江-从江一带下江群经历了成岩-高近变质-浅变质作用,基于Warr和Rice标样的成岩/变质界限,剖面可划分为一个成岩带、两个近变质带、一个转变带和一个浅变质带。结合华南地区新元古代构造运动,推断新元古界下江群经历的成岩-变质作用与晋宁运动引起的扬子地块与华夏地块碰撞拼贴有关。

关键词：结晶度伊利石-白云母多型伊利石(白云母)b0值成岩作用变质作用前寒武系黔东南

Nanocrystallization of Cementite in 0.4C-1Cr Steel During High-Power Surface Processing

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Journal of Wuhan University of Technology(Materials Science) 2005年第3期20卷 60-63页

作者：赵新奇 School of Materials Science and Engineering Tongji University Shanghai Baosteel Research Institute Shanghai 201900China

The microstructures of the nanocrystalline surface layer of a quenched and high temperature tempered 0. 4C- 1Cr steel induced by high-power surface processing （HPSP） technique were characterized by scan- ning eleetron microscopy and transmission electron microscopy. The results indicate that a nanocrystalline layer was fabricated on the surface of the steel 19 using HPSP treatment. The mean grain size in the surface layer is about 11 nm. The nanocrystallization of cementite is prior to that of the matrix phase, ferrite.

关键词： cementite high-power surface processing surface nanocrystallization

分子筛改性Co／SiO2.化剂对Fischer-Tropsch合成汽油类烃的影响

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石油化工 2008年第5期37卷 445-449页

作者：李宇萍王铁军吴创之吕永兴李海滨中国科学院可再生能源与天然气水合物重点实验室

在中孔SiO2.添加USY，HZSM-5，β分子筛组成双功能载体，并采用初湿浸渍法在载体上浸渍钴盐，制备了一系列分子筛改性的Co／SiO2.化剂，考察了分子筛的类型、HZSM-5分子筛的骨架硅铝比、HZSM-5分子筛在载体中的含量对Fischer-Tropsch... 详细信息

在中孔SiO2.添加USY，HZSM-5，β分子筛组成双功能载体，并采用初湿浸渍法在载体上浸渍钴盐，制备了一系列分子筛改性的Co／SiO2.化剂，考察了分子筛的类型、HZSM-5分子筛的骨架硅铝比、HZSM-5分子筛在载体中的含量对Fischer-Tropsch合成汽油类烃（C5-12.的影响。实验结果表明，载体中SiO2.分子筛共同作用，提高了催化剂的活性，并使产物分布向汽油类烃偏移，其中，以HZSM-5分子筛改性的Co／SiO2.化剂的催化性能最好。HZSM-5分子筛改性催化剂对催化性能的影响受其骨架硅铝比的影响。当骨架硅铝比n（SiO2.：n（Al2.3）=38、HZSM-5分子筛在载体中的质量分数为2.％时，CO转化率达到80％以上，汽油类烃的选择性高达55％，其中异构烷烃的选择性在10％以上。

关键词： Fischer-Tropsch合成钴/二氧化硅催化剂分子筛汽油类烃

Analysis of a kind of quantum cryptographic schemes based on secret sharing

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Science China(Physics,Mechanics & Astronomy) 2009年第9期52卷 1313-1316页

作者： ZHANG XingLan1 & JI DongYao2.1 College of Computer Science and Technology, Beijing University of Technology, Beijing 10012., China 2.State Key Laboratory of Information Security, Graduate University of Chinese Academy of Sciences, Beijing 100049, China College of Computer Science and Technology Beijing University of Technology Beijing 100124 China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China

Recently, Yang et al. proposed a kind of quantum cryptographic schemes based on secret sharing. The main idea is drawn from the case, where any n participants who share a secret K can co-operate as K does. This process can be applied to encryption, authentication, signature and so on. Unfortunately, since there is no identity authentication of the share's holder, these schemes inherit the limitation of secret sharing in practice. If some participants do not follow the protocol, the protocol would be a failure at last. Moreover, these schemes encounter another serious attack. Any two participants can co-operate to defeat the schemes by sending different shares to the parties unknown to the distributor of the secret K, such that these parties can execute the protocol as well. The attack proves that it is not enough for quantum cryptographic schemes that only the secret key is secure.

关键词： quantum identity authentication quantum secure direct communication quantum signature secret sharing