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Magnetic mineralogy of the Hongqiling Cu-Ni sulphide deposit: Implications for ore genesis

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Progress in Natural science:Materials International 2007年第10期17卷 1192-1198页

作者： Xi Aihua1,2. Ge Yuhui1, Cai Yuanfeng2.and Zhang Xuefeng3(1. Faculty of Resources & Environment, Southwest Petroleum University, Chengdu 610500, china 2. State Key laboratory for Endogenic Metal Deposit Research, Nanjing University, Nanjing 2.0093, china 3. Department of Natural Resources & technology information, china University of Petroleum, Beijing 102.49, china) Faculty of Resources & Environment Southwest Petroleum University Chengdu 610500 China State Key laboratory for Endogenic Metal Deposit Research Nanjing University Nanjing 210093 China Department of Natural Resources & technology information China University of Petroleum Beijing 102249 China

Pyrrhotite is one of the common ore minerals in Cu-Ni sulphide deposits, but only monoclinic pyrrhotite is ferromagnetic at room temperature. X-ray and EPA analyses reveal that most pyrrhotite forming sideronitic texture in the Hongqiling Cu-Ni sulphide deposit is monoclinic, but that in the massive ore is a mixture of monoclinic and hexagonal pyrrhotites. Differential thermal and magnetic- thermogravimetric analyses of massive ore indicate a magnetic transition and heat absorption at 32.℃, suggesting that this temperature is the thermomagnetic and phase transition point of pyrrhotite. For massive pyrrhotite ores heated at 400oC for 30 h and then quenched by cool water, the monoclinic pyrrhotite (mpo) transforms completely into the hexagonal pyrrhotite (hpo). However, all the pyrrhotites resulting from slow cooling of the sample in air are mpo. These results indicate that transformation between hpo and mpo depends upon the cooling rate. Therefore, massive ores in this deposit might have been formed via rapid cooling of ore melts. On the other hand, it is significant to study the effect of the ratio of the magnetite in total ores on the genesis of magmatic Cu-Ni suphide deposits.

关键词： pyrrhotite magnetite genesis of Cu-Ni sulphide deposit Hongqiling.

Super-orthogonal space-time code design based on the trellis diagram integrated operation

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science china({2. sciences) 2011年第7期54卷 1481-1490页

作者： AO Jun 1,2.MA ChunBo 1,AO FaLiang 1 & LIAO GuiSheng 3 1 College of information and Communication,Guilin University of Electronic and technology,Guilin 541004,{2. 2.national Key laboratory of Electromagnetic Environment,QingDao,2.6107,{2. 3 national Lab of Radar Signal Processing,Xidian University,Xi’an 710071,{2. 1. College of information and Communication Guilin University of Electronic and Technology Guilin 541004 China2. National Key Laboratory of Electromagnetic Environment QingDao 266107 China3. National Lab of Radar Signal Processing Xidian University Xi’an 710071 China

By studying the super-orthogonal space-time coding designs for 2.transmit antennas and superquasi orthogonal space-time coding designs for 4 transmit antennas,a novel super-orthogonal space-time coding design for 4 transmit antennas is *** exploiting the inherent structure association between OSTBC and QOSTBC,the proposed schemes can obtain the full-rate and good performance while keeping the coding complexity as super-orthogonal space-time coding schemes for 2.transmit *** results demonstrate that the proposed schemes outperforms the existing super-quasi orthogonal space-time coding schemes by almost 2.dB.

关键词： STBC TCM SOSTTC SQOSTTC

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

Formation of complexes of Rubisco-Rubisco activase from La^3+, Ce^3+ treatment spinach

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science china Chemistry 2005年第1期48卷 67-74页

作者： HONG Fashui1, LIU Chao1, ZHENG Lei1, WANG Xuefeng1, WU Kang1, SONG Weiping1, Lü Shipeng1, TAO Ye2.& ZHAO Guiwen3 1. College of Life sciences, Suzhou Universty, Suzhou 2.5006, china 2. Synchrotron Radiation {2., Institute of High Energy Physics, The Chinese Academy of science, Beijing 100039, china 3. Chemical Department, University of science and technology of china, Hefei 2.002., china 1. College of Life sciences Suzhou Universty 215006 Suzhou China 2. Synchrotron Radiation laboratory Institute of High Energy Physics The Chinese Academy of Science 100039 Beijing China 3. Chemical Department University of Science and Technology of China 230026 Hefei China

The complex of Rubisco and Rubisco activase from LaCl3-, CeCl3- treated spinach in vivo is induced. SDS-PAGE result shows that the purified proteins from LaCl3-, CeCl3- treated spinach have not only large and small subunits (55 kD, 14.4 kD) of Rubisco, but also two large subunits of 45 kD and 41 kD near the large subunits of Rubisco. Native-PAGE shows that the purified proteins from LaCl3-, CeCl3- treated spinach have not only a band of Rubisco (560 kD), but also a band of about 1100 kD, about twice distant from Rubisco, which might be a complex of Rubisco and Rubisco activase. The purified enzyme activities from LaCl3-, CeCl3-treated spinach are 1.8 and 2.8 times that of the control,the intensities of absorption and fluorescence are sig- nificantly higher than that of the purified Rubisco from the control, and the total sulfhydryl groups and available sulfhydryl groups are 36—39 –SH per mol enzyme, 14—2. –SH per mol enzyme more than those of the purified Rubisco from the control, respectively. The CD spectra show that the secondary structure of the purified enzyme from LaCl3-, CeCl3 -treated spinach is very dif- ferent from the control. The enzyme activities from LaCl3-, CeCl3- treated spinach in vivo are 1.5 and 1.9 times those of the control.

关键词： La3+, Ce3+, spinach, Rubisco, complex of Rubisco and Rubisco acitivase, spectral characteristics.

Dominant point detecting based non-uniform B-spline approximation for grain contour

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science china(Technological sciences) 2007年第1期50卷 90-96页

作者： ZHAO XiuYang1, YIN YanSheng1,2.& YANG Bo3 1 Shandong Key laboratory of Engineering Ceramics, Shandong University, Jinan 2.0061, china 2.School of Materials, Ocean University of china, Qingdao 2.6003, china 3 State Key laboratory of Advanced technology for Materials Synthesis and Processing, Wuhan University of science and technology, Wuhan 430070, china 1. Shandong Key laboratory of Engineering Ceramics Shandong University Jinan 250061 China 2. School of Materials Ocean University of China Qingdao 266003 China 3. State Key laboratory of Advanced technology for Materials Synthesis and Processing Wuhan University of Science and Technology Wuhan 430070 China

Three-dimension reconstruction from serial sections has been used in the last decade to obtain information concerning three-dimensional microstructural ge-ometry. One of the crucial steps of three-dimension reconstruction is getting compact and fairing grain contours. Based on the achievement of closed raw con-tours of ceramic composite grains by using wavelet and level set, an adaptive method is adopted for the polygonal approximation of the digitized raw contours. Instead of setting a fixed length of support region in advance, the novel method computes the suitable length of support region for each point to find the best es-timated curvature. The dominant points are identified as the points with local maximum estimated curvatures. Periodic closed B-spline approximation is used to find the most compact B-spline grain boundary contours within the given tolerance. A flexible distance selection approach is adopted to obtain the common knot vector of serial contours consisting of less knots that contain enough degrees of freedom to guarantee the existence of a B-spline curve interpolating each contour. Finally, a B-spline surface interpolating the serial contours is generated via B-spline surface skinning.

关键词： composite B-spline dominant points control points grain contour

Bell violation for the thermal states of an XXZ spin chain with Dzialoshiski-Moriya interaction

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science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2074-2079页

作者： MA XiaoSan 1 & WANG AnMin 2.1 School of Electric Engineering and information,Anhui University of technology,Maanshan 2.3002.{2. 2.Department of Modern Physics,University of science and technology of china,Hefei 2.002.,{2. 1. School of Electric Engineering and information Anhui University of Technology Maanshan 243002 China2. Department of Modern Physics University of Science and Technology of China Hefei 230026 China

The effect of Dzialoshiski-Moriya (DM) interaction on the violation of Bell inequality for thermal states of interacting qubits via a two-qubit XXZ spin chain is *** results imply that the DM interaction and anisotropy taking a large positive value can enhance the Bell violation and improve the threshold temperatures of *** the comparison between the Bell violation and thermal entanglement,we find that the threshold temperatures of thermal entanglement are higher than those of the Bell *** implies that some states are entangled but the Bell inequality is not violated.

关键词： Bell violation threshold temperatures DM interaction

On degrees of freedom of the cellular network

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science china({2. sciences) 2010年第05期53卷 1034-1043页

作者： SUN Jun 1,2., LIU YingZhuang 1,2.& ZHU GuangXi 1,2.1 Department of Electronics and information Engineering, Huazhong University of science and {2., Wuhan 430074, china 2.Division of Optical Network and Intelligent Communication, Wuhan national laboratory for Optoelectronics, Wuhan 430074, china 1. Department of Electronics and information Engineering Huazhong University of Science and Technology Wuhan 430074 China2. Division of Optical Network and Intelligent Communication Wuhan National Laboratory for Optoelectronics Wuhan 430074 China

In this paper, we consider the capacity limits of the cellular network by modeling it as consisting of two mutually interfering multiple access channels with multiple antennas at each receiver (e.g., base station). By developing a tight outerbound as well as an achievable scheme which exploits the idea of interference alignment, we are able to exactly characterize the sum degrees of freedom (DoF) of the network when the channel coefficients are timeor frequency-varying, which equals KM K+min(M,K) (where M and K denote the number of receiver antennas and number of users in per cell, respectively) per cell. From the DoF result, it can be observed that in addition to the multi-user gain which has been reported for the network with single-antenna BSs, there also exists the multi-antenna gain in the cellular network. In particular, when the number of users is large, we can nearly achieve the interference-free DoF of a cellular network with multiple-antenna BSs, which is a somewhat surprising result.

关键词： capacity degrees of freedom cellular network interference alignment interference channel MIMO

Tensile and compression properties of Zr-based bulk amorphous alloy at different temperatures

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science china(Technological sciences) 2005年第5期48卷 489-495页

作者： WANG Xu1,3, LOU Decheng1, GAO Zhanjun4, LIU Lei1, LIANG Hongmei1, WANG Qingfeng1, LI Qiang1,3 & MA Mingzhen1,2.1. Key laboratory of Metastable Materials science & {2. of Hebei, Yanshan University, Qinhuangdao 066004, china 2. national Key laboratory for Precision Hot Processing of Metals, Harbin Institute of {2., Harbin 150001, china 3. College of Mechanical Engineering, Yanshan University, Qinhuangdao 066004, china 4. Chinese Academy of Engineering, Beijing 100038, china 1. Key laboratory of Metastable Materials science & {2. of Hebei Yanshan University 066004 Qinhuangdao China 2. College of Mechanical Engineering Yanshan University 066004 Qinhuangdao China 3. Chinese Academy of Engineering 100038 Beijing China 4. national Key laboratory for Precision Hot Processing of Metals Harbin Institute of Technology 150001 Harbin China

Mechanical properties of the Zr41Ti14Cu12.5Ni10Be2..5 bulk amorphous alloy at different temperatures were investigated. The compression test was carried out on a Gleebe-32.0 machine at 345 and 375°C, respectively, in the supercooled liquid region. It is shown that decreasing the compressive rate and increasing temperature have a similar influence trend on the compressive behavior of the bulk amorphous alloy. Room and low temperature tensile strengths were tested on the Instron materials testing system. At low temperature, the tensile strength decreased with decreasing of the testing temperature. Hardness measurement indicated that below the glass transition temperature, the hardness decreased with increasing of the annealing temperature and duration time. It, however, increased when the annealing treatment was performed above the glass transition temperature.

关键词： Zr41Ti14Cu12.5Ni10Be2..5 bulk amorphous alloy, mechanical properties, compressive deformation.

Multi-materials drop-on-demand inkjet technology based on pneumatic diaphragm actuator

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science china(Technological sciences) 2010年第6期53卷 1605-1611页

作者： XIE Dan1,2.ZHANG HongHai1,2.SHU XiaYun1,2.Xiao JunFeng1,2.& CAO Shu1,2.1Institute of Micro-Systems,School of Mechanical science and Engineering,Huazhong University of science and {2.,Wuhan 430074,china 2.uhan national laboratory for Optoelectronics,Wuhan 430074,china 1. Institute of Micro-Systems School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China2. Wuhan National Laboratory for Optoelectronics Wuhan 430074 China

Micro-droplet jetting belongs to the field of precision fluid dispensing *** traditional subtraction manufacture process,micro-droplet jetting as an additive fabrication technique with features of non-contact and data-driven represents a new development trend of modern manufacturing *** this paper,the design,fabrication and performance of a multi-materials drop-on-demand (DOD) inkjet system based on pneumatic diaphragm actuator were *** capturing the droplet ejection process and measuring the droplet dimension,a self-made in situ imaging system based on time delayed external trigger was set *** performance of the generator was studied by adjusting the structure and control ***,the influence of fluid properties on the droplet ejection process was experimentally ***-solderballs of 160.5 μm in diameter and UV curing adhesive micro-bumps of 346.94 μm in contact diameter with the substrate were *** results demonstrated that the DOD inkjet generator possesses characteristics of robust,easy to operate and maintain,and able to withstand high temperature as well as applicability to a wide variety of materials including polymers,low melting point resin and high melting point *** system has a great potential of being used in the fields of IC and MEMS packaging,3D printing,organic semiconductor fabrication,and biological and chemical analysis.

关键词： micro-droplet jetting drop on demand pneumatic diaphragm actuator multi-materials