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Petrogenesis of Songshugou dunite body in the Qinling orogenic belt, Central China: Constraints from geochemistry and melt inclusions

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Science China Earth Sciences 2005年第8期48卷 1146-1157页

作者： SU Li1,2, SONG Shuguang3.& ZHOU Dingwu1 1. key laboratory of Continental Dynamics of the Ministry of Education, Department of Geology, Northwestern university, {3.’an 710069, China 2. The Geological Lab Center, China university of Geosciences (Beijing), Beijing 100083. China 3. key laboratory of Orogenic Belts of the Ministry of Education, Department of Geology, Peking university, Beijing 100871, China 1. key laboratory of Continental Dynamics of the Ministry of Education Department of Geology Northwestern University 710069 Xi’an China 2. The Geological Lab Center China University of Geosciences 100083 (Beijing)Beijing China 3. key laboratory of Orogenic Belts of the Ministry of Education Department of Geology Peking University 100871 Beijing China

The Songshugou dunite body, which occupies an area of about 20 km2, is the largest ultramafic massif in the eastern Qinling orogenic belt, Central China. The major compo-nent of this body is dunitic rocks including mylonitic dunite and coarse-grained dunite; they oc-cupy about 95 vol% of the total body. Petrography, mineral composition, major and trace ele-ments and primitive melt inclusions have been investigated in this paper; all revealed that this dunite body is the product of melt-rock interaction by porous percolation flow. In comparison with dunite sills or veins in harzburgite from the basal part of Oman ophiolite, this dunite body is characterized by lower contents of Al2O3. CaO and HREE but higher content of highly incom-patible elements and Zr and Hf. The LREE enriched patterns and primitive mantle normalized spidergrams of trace elements are also different from the Oman dunite. Combining with melt in-clusions observed in olivines, we conclude that this dunite body is the product of large- scale porous percolation flow of high-MgO melts within depleted mantle peridotites. The high-MgO magma, in essence, was most probably produced at the hot head of an upwelling mantle plume. The occurrence of the Songshugou dunite body is closely associated with the activity of mantle super-plume in Neo-Proterozoic era in the Yangtze Craton.

关键词： Songshugou dunite body, geochemistry, melt inclusion, mantle plume, Qinling orogenic belt.

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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 {3. laboratory for Endogenic Metal Deposit Research, Nanjing university, Nanjing 210093. China 3. Department of Natural Resources & Technology Information, China university of Petroleum, Beijing 102249, 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 3.3., suggesting that this temperature is the thermomagnetic and phase transition point of pyrrhotite. For massive pyrrhotite ores heated at 400oC for 3. 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.

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Mechanism of Combustion Synthesis of TiC-Ti Cermet

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Journal of Wuhan university of Technology(Materials Science) 2007年第3期22卷 502-505页

作者：肖国庆 School of Materials Science and Engineering Xi’an University of Architecture and Technology

In order to investigate the mechanism of combustion synthesis of TiC-Ti cermet, a mixture of Ti and C was used for a combustion front quenching test, and the microstructural evolution in the quenched sample was analyzed by scanning electron microscopy （SEM） and energy dispersive X-ray （EDX）. Also, a temperature-time profile of the combustion reaction was measured. Based on the experimental results, a reaction-dissolution-precipitation mechanism of the combustion synthesis of TiC-Ti was proposed.

关键词： TiC-Ti cermet combustion synthesis combustion front quenching method

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Coordination of distinctive pesticide adjuvants and atomization nozzles on droplet spectrum evolution for spatial drift reduction

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Chinese Journal of Chemical Engineering 2024年第2期66卷 250-262页

作者： Shidong Xue Jingkun Han xi xi Zhong Lan Rongfu Wen Xuehu Ma state key laboratory of Fine Chemicals Liaoning Key Laboratory of Clean Utilization of Chemical ResourcesInstitute of Chemical EngineeringSchool of Chemical EngineeringDalian University of TechnologyDalian 16024China School of Fashion and Textiles The Hong Kong Polytechnic UniversityHong Kong 999077China China Tianchen Engineering Corporation Tianjin 300400China School of Energy and Power Engineering Dalian University of TechnologyDalian 116024China

Pesticide adjuvants,as crop protection products,have been widely used to reduce drift loss and improve utilization efficiency by regulating droplet ***,the coordinated regulation mechanisms of adjuvants and nozzles on droplet spectrum remain ***,we established the relationship between droplet spectrum evolution and liquid atomization by investigating the typical characteristics of droplet diameter distribution near the *** on this,the regulation mechanisms of distinctive pesticide adjuvants on droplet spectrum were clarified,and the corresponding drift reduction performances were quantitively evaluated by wind tunnel *** shows that the droplet diameter firstly shifts to the smaller due to the liquid sheet breakup and then prefers to increase caused by droplet *** the surface tension of sprayed liquid facilitates the uniform liquid breakup and increasing the viscosity inhibits the liquid deformation,which prolong the atomization process and effectively improve the droplet *** a result,the drift losses of flat-fan and hollow cone nozzles are reduced by about 50%after adding organosilicon and vegetable oil *** contrast,the air induction nozzle shows a superior anti-drift ability,regardless of distinctive *** findings provide insights into rational adjuvant design and nozzle selection in the field application.

关键词： Pesticide drift Spray droplets Particle size distribution Spray atomization Transport processes Adjuvants

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Thermoelastic properties of sandwich materials with pin-reinforced foam cores

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Science China(Technological Sciences) 2008年第12期51卷 2059-2074页

作者： LU TianJian1,LIU Tao2,3.& DENG ZiChen2,4 1 MOE key laboratory of Strength and Vibration,School of Aerospace,xi’an Jiaotong {3.,xi’an 710049,China 2 Department of Engineering Mechanics,Northwestern Polytechnical {3.,xi’an 710072,China 3.Department of Engineering,{3. of Cambridge,Cambridge CB2 1PZ,UK 4 state key laboratory of Structural Analysis of Industrial Equipment,Dalian {3. of Technology,Dalian 116024,China MOE key laboratory of Strength and Vibration School of Aerospace Xi’an Jiaotong University Xi’an 710049 China Department of Engineering Mechanics Northwestern Polytechnical University Xi’an 710072 China Department of Engineering University of Cambridge Cambridge CB2 1PZ UK state key laboratory of Structural Analysis of Industrial Equipment Dalian University of Technology Dalian 116024 China

Pin-reinforced foam is a novel type of sandwich core materials formed by inserting pins(trusses) into a foam matrix to create a truss-like network reinforced foam *** loading,the pins deform predominantly by local stretching whilst the deformation of foam is governed by local *** paper presents a theoretical study on the thermoelasticity of pin-reinforced foam sandwich *** calculate the effective thermoelastic properties of pin-reinforced foam cores,the energy-based homogenization approach is employed to develop a micromechanics-based model,calibrated by the existing experimental *** is found that the stiffness of the sandwich core is mainly governed by pin reinforcements:the foam matrix contributes little to sandwich *** with traditional foam cores without pin reinforcements,the changes in inplane thermal expansion coefficients are not vigorous as a result of pin reinforcements,while the through-thickness thermal expansion coefficient changes *** is also demonstrated that it is possible to design materials with zero or negative thermal expansion coefficients under such a context.

关键词： sandwich panel pin reinforcement analytical solutions homogenization thermoelasticity thermal expansion

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Matching Strategies and Fuzzy URLs in Web Based Component Retrieving

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Wuhan university Journal of Natural Sciences 2001年第Z1期6卷 283-287页

作者： Wang Ying 1,2 , Sang Da yong 2, 3.1. College of Management, xi’an Jiaotong university, xi’an 710049,China 2.College of Engineering, Air Force university of Engineering, xi’an 71003.,China 3. state key {3. of Software Engineering, Wu College of Management Xi’an Jiaotong University Xi’an China College of Engineering Air Force University of Engineering Xi’an China state key laboratory of Software Engineering Wuhan University Wuhan China

The World Wide Web (WWW) has greatly changed the way of component based software reuse, for large number of components provided by different vendors become available and it's rather difficult to find and choose what we in fact need. To make large amount of the components collaborate, an information exchanging model is essential. In order to retrieve and search the suitable or usable components more effectively, some techniques should be taken into account. Among these techniques, matching strategies and fuzzy URL semantics are significant for the former help us to find components which could be reused and the other both to broaden the searching areas and use some uncertain information to make the searching more purposive. A brief discuss on an abstract component model (UACModel) is begun, which was proposed to promote the interoperability and information exchange among various reusable component libraries (RCLs), and a framework for component retrieval. Then the emphases are put on some matching strategies, especially incomplete ones that encourage reuse through component customization, and fuzzy URL extensions to be supported and realized.

关键词： component reuse interoperability model component retrieval index repository reusable component library (RCL)

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A first-principles study of dihydroazulene as a possible optical molecular switch

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Science China(Physics,Mechanics & Astronomy) 2011年第3期Mechanics & Astronomy) .卷 437-441页

作者： xiA CaiJuan1, LIU DeSheng2,3.& LIU HanChen1 1 School of Science, xi’an Polytechnic university, xi’an 710048, China 2 School of Physics, state key laboratory of Crystal Materials, Shandong university, Jinan 250100, China 3.Department of Physics, Jining university, Qufu 273.55, China 1. School of Science Xi’an Polytechnic University Xi’an 710048 China2. School of Physics State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China3. Department of Physics Jining University Qufu 273155 China

By applying nonequilibrium Green's function formalism combined with first-principles density functional theory, we investigate the electronic transport properties of the dihydroazulene optical molecular switch. Three kinds of adsorption sites including the hollow, bridge and top sites are studied. The two forms of this molecule, namely the open form and the closed form, can reversibly switch from each other upon photoexcitation. Their transmission spectra are remarkably distinctive. Theoretical results show that the current of the closed form is always significantly larger than that of the open form for all three adsorption sites, which promises this system as possibly one of the good candidates for optical switches due to its unique advantage, and which may have some potential applications in the future molecular circuit.

关键词： molecular switch nonequilibrium Green’s function electronic transport density functional theory

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EXPERIMENTAL　RESEARCH　ON　DIRECTIONAL　SOLIDIFICATION　OF　Al－4．5wt％Cu　ALLOY　BY　ACRT　METHOD

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Acta Metallurgica Sinica(English Letters) 1996年第1期9卷 17-22页

作者： JIE Wanqi(state key laboratory of Solidification Processing,Northwestern Polytechnical {3.,xi’an 710072,China) Northwestern Polytechnical Univ Xi'an China

Accelerated crucible rotation technique(ACRT) has been used for the directional solidification of Al-4.5wt% Cu binary *** rotating the crucible at varying rate and direction,forced liquid flows are aroused These flows include Ekman flow,Couette flow and Spiral Shear ***,Ekman flow acts directly at the L/S interface,changes diffusion and heat exchange conditions and has strong influences on the morphology of L/S *** results show that,compared with normal Bridgman specimens,the solidification region is much narrower and the cell spacing is much smaller in ACRT *** influences become much stronger when the accelerating rate is increased.

关键词： accelerated crucible rotation technique(ACRT) Al-4.5wt%Cu directional solidification morphology of L/S interface cell spacing

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key Technologies for High Speed WLAN

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ZTE Communications 2006年第2期4卷 19-22页

作者： Chen Yanhui (state key Lab of integrated Service {3.s, xidian university, xi’an 710071, China)

The rapid development of Wireless Local Area network (WLAN) has not yet broken the bottleneck that the low transmission speed hinders the further development of WLAN. Now, some key technologies for next generation mobile communications can solve the problem by supporting high-speed transmission and ensuring reliable performance. IEEE 802.11n has made general amendment to 802.11. Based on IEEE 802.11n, the transmission speed can be doubled by the application of Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) technologies on the physical layer. In addition, the enhanced Medium Access Control (MAC) system performance, optimized data frame and improved network throughput can all be achieved by the adoption of frame convergence, Transmission Opportunity (TXOP) and block-acknowledge technologies on the MAC layer. A new error correction method, called Low Density Parity Check Code (LDPC), can also be adopted for the receiver to enjoy low Bit Error Ratio (BER) with low S/N, thus improving signal coverage.

关键词： key Technologies for High Speed WLAN IEEE LDPC TXOP MIMO MAC OFDM STBC MPDU

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一种新的预报单光子源诱骗态量子密钥分发方案

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物理学报 2008年第9期57卷 5600-5604页

作者：权东晓裴昌幸朱畅华刘丹西安电子科技大学综合业务网国家重点实验室西安710071

提出一种新的预报单光子源诱骗态量子密钥分发方案.在发端采用参量下变换产生纠缠光子对,其中之一用来进行预报探测,根据探测结果将另一路光脉冲分成两个集合,其中预报探测有响应的脉冲集合用作信号态,无响应的脉冲集合作为诱骗态.由于... 详细信息

提出一种新的预报单光子源诱骗态量子密钥分发方案.在发端采用参量下变换产生纠缠光子对,其中之一用来进行预报探测,根据探测结果将另一路光脉冲分成两个集合,其中预报探测有响应的脉冲集合用作信号态,无响应的脉冲集合作为诱骗态.由于探测效率的问题,这两个集合都是有光子的,通过这两个集合的通过率和错误率估计出单光子的通过率和错误率.此方法不需要改变光强,简单可行.仿真结果表明:该方法可以达到完美单光子源的安全通信距离;与预报单光子源的量子密钥分发相比,密钥产生率有了很大的提高;和三强度预报单光子源诱骗态量子密钥分发的密钥产生率相差不大.

关键词：量子保密通信量子密钥分发诱骗态预报单光子源

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