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Forecast of blind ore body in Zhangcaigou area around Wulaga gold deposit

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Global Geology 2006年第1期9卷 13-18页

作者： Guoxue Wu Guohua chen Zhigang lü College of Earth Sciences Jilin University Changchun 130061 Jilin China

By the study of metallogenetic conditions and ore-controlling factors, the metallogenetic indicators in geology, geochemistry and geophysics about Wulaga gold deposit have been obtained. Using the indicators the blind ore bodies have been forecasted in Zhangcaigou area. By drilling check, a gold-bearing ore body with 3 m thickness in an average tenor of 20.4×10 -6 at the depth of 70 m has been found in the forecast area. It shows that the forecast method should be effective.

关键词： Wulaga gold deposit blind ore body mineral forecast

Influence of an Electronic Field on the GMI Effect of Fe-based Nanocrystalline Microwire

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Nano-Micro letters 2013年第1期5卷 13-17页

作者： Q.Zhang D.l.chen X.li P.X.Yang J.H.Chu Z.J.Zhao Key laboratory of Polar Materials and Devices Ministry of EducationDepartment of Electronic EngineeringEast China Normal University Engineering Research Center for Nanophotonics & Advanced Instrument Ministry of EducationDepartment of PhysicsEast China Normal University

In this work, a Fe-based nanocrystalline microwire of 20 mm in length and 25 μm in diameter was placed in the center of a 316 stainless steel pipe. The pipe was 500 μm in diameter and a little shorter than the microwire. A series of voltages were applied on the pipe to study the influence of the electrical field on the Giant-Magneto-Impedance(GMI) effect of the microwire. Experimental results showed that the electronic field between the wire and the pipe reduced the hysteresis of the GMI effect. The results were explained based on equivalent circuit and eddy current consumptions analysis.

关键词： GMI Eddy consumptions Electronic field Equivalent circuit

Symmetric Identities from an Invariant in Partition Conjugation and Their Applications in <i>q</i>-Series

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Open Journal of Discrete Mathematics 2014年第2期4卷 36-43页

作者： Sandy H. l. chen School of Science Tianjin Chengjian University Tianjin China

For every partition and its conjugation , there is an important invariant , which denotes the number of different parts. That is , . We will derive a series of symmetric q-identities from the invariant in partition conjugation by studying modified Durfee rectangles. The extensive applications of the several symmetric q-identities in q-series ?[1] will also be discussed. Without too much effort one can obtain much well-known knowledge as well as new formulas by proper substitutions and elementary calculations, such as symmetric identities, mock theta functions, a two-variable reciprocity theorem, identities from Ramanujan’s lost Notebook and so on.

关键词： Integer Partitions Conjugation Invariant -Series Symmetric Identities

Brief Introduction of CAI Shidong (also Shih-tung Tsai)

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Plasma Science and Technology 2010年第3期12卷 258-259页

作者： l. chen C. S. liu J. Van Dam

Shih-tung Tsai, a longtime professor of plasma physics at the Institute of Physics in Beijing, died in Beijing from liver cancer on 20 June 1996.

关键词： In CAI also Shih-tung Tsai Brief Introduction of CAI Shidong

Al_(80)Ni_6Y_8Co_4Cu_2 GlASS AllOYS CONTAINING NANOSCAlEPARTIClES BY ISOTHERMAl ANNEAlING OR QUENCHING

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Acta Metallurgica Sinica(English letters) 2000年第5期13卷 1039-1046页

作者： Z. Bian, G. He and G.l. chen (State Key laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China) J. lu, D.J. chen, G.C. Tu, G.J. chen and X.J. Hu (Shougang Metallurgical Research Institute, Beijing lab. for Adv. Metals and Mat. Univ. of Sci. and Technol. Beijing Beijing 100083 China Shougang Metall. Res. Inst. Beijing 100085 China

Al80Ni6 Y8 Co4 Cu2 amorphous ribbons were isothermally annealed and a mixed structure consisting of α-Al particle with a size of less than 15nm and Al3Ni compound with a size of about 30nm was obtained. The crystallization kinetics of Al80Ni6 Y8 Co4 Cu2 amorphous alloy shows that the precipitation of α-Al particles is the growth process controlled by diffusion of the solute elements rejected from the growing crystals. By quenching at different cooling rates, a mixed structure consisting of nanoscale α-Al particles and the remaining glass matrix or structure consisting of nanoscale particle (Al phase or Al3Ni compound) with a size of about 100nm was formed. The addition of Co elements and Cu elements to Al-Ni-Y alloy systems increases the glass formation ability of the alloy and the thermal stability of the supercooled liquid region against crystallization, which results from significant difference of atomic size, strong bonding nature among constituent elements and the low diffisivity of the solute elements due to the concentration gradient in the growing front of crystals.

关键词： a mixed structure nanoscale particle isothermal annealing cooling rate concentration gradient α-Al particle Al3Ni compound

DESIGN　AND　PREPARATION　OF　SIlICON　NITRIDE　COMPOSITE　WITH　HIGH　FRACTURE　TOUGHNESS　AND　NACRE　STRUCTURE

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Acta Metallurgica Sinica(English letters) 1996年第6期9卷 479-484页

作者： Y Huang H.N Hao Y.l. chen and B.l.Zhou (1)Department of Materials Science and Engineering, Tsinghua University,Beijing 100084, China 2)Institute of Metal Research, Chinese Academy of Sciences,Shenyang 110015, China ) Tsinghua Univ Beijing China

A new way of designing and preparing silicon nitride ceramic composite with high fracture toughness and nacre structure has been proposed. To mimic the laminated structure of nacre, Si_3N_4 matrix ceramic layer can be obtained through compacting rolling method. To mimic the secondary toughening of nacre structure, SiC whisker is added into Si_3N_4 and acts as the secondary toughening phase. Boron nitride (BN)is selected to mimic the organic layer in nacre so as to form the weak interfaces between Si_3N_4 layers. Alumina is added into BN to adjust the bonding strength of the *** Si_3N_4 sheets are stacked into the die after coating with BN. After the removal of the organic matter in them, the green body is hot pressed at 1820℃for 1.5 hours under N_2 atmosphere. The fracture toughness of the so-made Si_3N_4 composite at room temperature is 20.36MPa m￣(1/2), the three-point bending strength at room temperature is 651.47MPa. The crack spreads and deflects along the interface between BN and Si_3N_4 layer and extends through the BN layer into Si_3N_4 layer. The improvement of the fracture toughness may be due to the staircase-shape-like crack which provides the long crack path, the fracture and deformation of Si_3N_4 layer, and the pullout of SiC whiskers from the Si_3N_4 layer.

关键词： secondary toughening,compact rolling silicon nitride nacre Structure

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连续相位板面形的随机特性研究

物理学报 2014年第16期63卷 185-190页

作者：吕晨张蓉竹四川大学电子信息学院成都610064

根据连续相位板面形分布的随机特性,利用自相关函数和相关长度对其面形特性进行了分析.采用一个高斯型随机分布函数推导了相关长度与连续相位板远场分布之间的解析关系.利用数值算法计算了连续相位板远场分布的方差和能量利用率,并计算... 详细信息

根据连续相位板面形分布的随机特性,利用自相关函数和相关长度对其面形特性进行了分析.采用一个高斯型随机分布函数推导了相关长度与连续相位板远场分布之间的解析关系.利用数值算法计算了连续相位板远场分布的方差和能量利用率,并计算了不同的相关长度对连续相位板远场分布的具体影响.结果表明,连续相位板的相关长度越小,远场分布均匀性越好,焦斑形态更加接近于目标焦斑,同时具有较高的能量利用率.

关键词：连续相位板自相关函数相关长度远场分布

B2-YX(X=Cu,Rh,Ag,In)点缺陷结构及其基本物性的理论计算

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稀有金属材料与工程 2007年第12期36卷 2089-2093页

作者：陈律彭平韩绍昌湖南大学

采用第一原理赝势平面波方法,计算了B2-YX(X=Cu,Rh,Ag,In)金属间化合物的基本物性。通过对不同点缺陷结构形成热和形成能的计算与比较,分析和预测了B2-YX金属间化合物中点缺陷结构的种类与存在形式。结果表明:B2-YX点缺陷结构主要是X子... 详细信息

采用第一原理赝势平面波方法,计算了B2-YX(X=Cu,Rh,Ag,In)金属间化合物的基本物性。通过对不同点缺陷结构形成热和形成能的计算与比较,分析和预测了B2-YX金属间化合物中点缺陷结构的种类与存在形式。结果表明:B2-YX点缺陷结构主要是X子晶格上的空位与Y子晶格上的反位,在富Y的YX金属间化合物中主要为X空位,在富X的YX金属间化合物中则主要是X反位。通过对B2-YX金属间化合物完整晶体与点缺陷结构Cauchy压力参数C12-C44和G/B0值的比较,发现点缺陷能明显提高B2-YX金属间化合物的室温塑性,推测这很可能是含有点缺陷的实际B2-YX多晶材料比无缺陷理想单晶和NiAl多晶材料表现出更好室温塑性的原因之一。

关键词： B2型Y(钇)基金属间化合物点缺陷第一原理赝势平面波方法塑性

基于区块链的细粒度云数据安全存储与删除方案

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电子与信息学报 2021年第7期43卷 1856-1863页

作者：周由胜陈律君重庆邮电大学计算机科学与技术学院重庆400065 重庆邮电大学网络空间安全与信息法学院重庆400065

在基于云计算的存储与删除服务中,由于外包数据所有权和管理分离,现有的逻辑删除机制使云上的数据很容易暴露给未经授权的用户,甚至云服务器可能未遵循用户要求删除相应数据。为此,该文提出一种细粒度的安全云端数据存储与删除方案。基... 详细信息

在基于云计算的存储与删除服务中,由于外包数据所有权和管理分离,现有的逻辑删除机制使云上的数据很容易暴露给未经授权的用户,甚至云服务器可能未遵循用户要求删除相应数据。为此,该文提出一种细粒度的安全云端数据存储与删除方案。基于椭圆曲线构造了基于密文策略的属性基加密以实现外包数据细粒度访问控制,应用区块链实现可公开验证的安全数据删除。该文方案具有责任可追踪性以及两方删除与可验证性等特性。理论分析与实验结果表明该文方案具有较好的安全性和较高的性能,能够满足云数据共享与安全删除的需求。

关键词：云存储安全删除属性加密区块链公开验证