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Science china(Physics,Mechanics & Astronomy) 2012年第4期Mechanics & Astronomy) .卷 649-653页

作者： LI XiaoWei 1,2*,CHEN HuaBao 1 & LIU ShuJing 1 1 School of Physics and electronic Electrical engineering,Huaiyin Normal university,Huaian 223300,china 2 State Key Laboratory of Functional Materials for Informatics,Shanghai institute of Microsystem and information technology,Chinese Academy of Sciences,Shanghai 200050,china School of Physics and electronic Electrical engineering Huaiyin Normal University Huaian China State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai China

Using the extended Blonder-Tinkham-Klapwijk formalism,we investigate the conductance spectra of graphene ferromagnet/p wave superconductor *** is found that the conductance spectra are affected by the p wave pairing *** ferromagnetic exchange energy in the ferromagnet can suppress Andreev retroreflection but enhance the specular Andreev reflection in graphene ferromagnet/p wave superconductor *** conductance decreases with increasing exchange energy Eh for EhEF.

关键词： graphene ferromagnet p wave superconductor tunneling conductance

Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South china

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Science china Earth Sciences 2006年第3期49卷 225-241页

作者： ZUO Jingxun1,2, TONG Jinnan3, QIU Haiou4 & ZHAO Laishi3 1. Nanjing institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, china 2. Henan institute of Geological Survey, zhengzhou 450007, china 3. State Key Laboratory of Geological Processes and Mineral Resources at china university of Geosciences, Wuhan 430074, china 4. Faculty of Material Sciences and Chemical engineering, china university of Geosciences, Wuhan 430074, china Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Henan institute of Geological Survey Zhengzhou China State Key Laboratory of Geological Processes and Mineral Resources at china university of Geosciences Wuhan China Faculty of Material Sciences and Chemical engineering China University of Geosciences Wuhan China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South china, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 13C background values are intensively controlled by palaeogeographic environment. In general, δ 13C values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze Region.

Tribological Properties of SiC/Cu Composite at High Temperature

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Journal of Wuhan university of technology(Materials Science) 2009年第6期24卷 888-891页

作者：范冰冰张锐 zhengzhou institute of Aeronautical Industry Management School of Materials Science & engineering Zhengzhou University

SiC/Cu composites were prepared by hot pressing. The high temperature tribological properties of the composites were investigated. XRD, SEM techniques were carried out to characterize the samples. It is found that the friction coefficient of SiC/Cu composites increases with the increasing SiC content. The SiC reinforcement particles are worn down other than removed by pulling out during the wear test. Oxidation of Cu debris leads to the smooth contacting surface. Ring crack is formed under the cyclic wear test. The crack propagates through the damaged matrix and along the brittle interface between SiC particles and Cu matrix.

关键词： SiC/Cu composite tribological properties high temperature wear ring crack

A new policy to solve routing conflicts in shuffle-exchange networks

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Science china(information Sciences) 2011年第7期54卷 1512-1523页

作者： GE FangBin 1,ZHAO Min 1,ZHANG Tao 1 & WANG JianXin 2 1 College of Command Automation PLA university of Science and technology,Nanjing 210007,china 2 institute of china electronic System engineering,Beijing 100039,china College of Command Automation PLA university of Science and technology Nanjing China institute of china electronic System engineering Beijing China

Batch routing is an important approach for solving routing conflicts in SE (shuffle-exchange) ***,the complexity of batching and the uncertainty of batch size makes this approach *** on sequence division and routing coding concepts,we propose a method for detecting routing conflicts in an SE network,known as dividing detection that is more efficient than the method for window *** addition,a new conjecture relating to routing policies in SE networks is *** is proved using a constructive approach when n < *** on the conjecture,a new routing scheme for SE networks is *** this scheme,all the input signals can be transfered without conflicts and within two batches,while the efficiency of the batch routing is noticeably improved.

关键词： shuffle-exchange network sequence division routing coding transition sequence educed sequence

Ant colony algorithm based restoration routing for WDM networks

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微计算机信息 2008年第33期 99-101页

作者： JIAN Yao-bo RUAN Shuang-chen YANG Chun-yong(institute of Optoelectronics Science and engineering,Huazhong university of Science and technology,430074 Wuhan china)(College of electronic Science and technology,ShenZhen university,518060 Shenzhen china)(College of electronics & information engineering,South-central university for Nationalities,430074 Wuhan china)

Ant colony algorithm-restoration algorithm(ACA-RA)is a novel simulated evolutionary *** is a population-based approach,which allows positive feedback to be used as the primary search mechanism and provides a new method for compli-cated combinatorial optimization *** this paper,selecting strategy,local searching and information modification are *** improved algorithm is used to search optimal restoration routes in case various failures take place in WDM *** valid result is proven by an algorithm simulation in a practical network chinaNET.

关键词： wavelength division multiplexing ant colony algorithm wavelength routing open shortest path first algorithm breath-first-search algorithm

Electrical property of 8-mol% yttria-stabilized zirconia electrolyte by spark-plasma sintering

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Science china(Technological Sciences) 2004年第5期47卷 569-576页

作者： JIAN Jiawen1,2, CHANG Aimin3, YANG Bangchao2 & ZHANG Yikang4 1. The School of information Science engineering, Ningbo university, Ningbo 315211, china 2. The School of Microelectronics and Solid-state electronics, university of electronic Science and Tech-nology of china, Chengdu 610054, china 3. The Xinjiang Technical institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi 830022, china 4. Hongtak (Chengdu) electronic Co., Ltd, Chengdu 610041, china Correspondence should be addressed to Jian Jiawen The School of information Science engineering Ningbo University Ningbo China The School of Microelectronics and Solid-state electronics University of Electronic Science and Technology of China Chengdu China The Xinjiang Technical institute of Physics and Chemistry Chinese Academy of Sciences Urumqi China Hongtak (Chengdu) electronic Co. Ltd Chengdu China

Spark-plasma sintering (SPS) process was used to sinter ZrO2 (8Y) powders, and a relative density of 99% has been reached at a low temperature (1350°C) and short dwelling time (10 min) compared to the conventional sintered identical samples (1450°C 4 h)(CS). By the X-ray diffraction (XRD) patterns, the microstructure of the SPS pellet and CS pellet are both indexed by the cubic unit cell (Fm3m). The finer crystallite size (D111) of the SPS pellet is 154 nm and D111 of the CS pellet is more than 1 μm. The AC impedance spectroscopy shows that the ionic conductivity of SPS pellet is different from that of CS pellet. The activation energy for the SPS ceramics, estimated from the slope in the range of 400–800°C, was 91 kJ mol?1, which is in good agreement with CS pellet (96 kJ mol?1), indicating that the conduction mechanism in SPS ceramics is similar to that in CS ceramics.

关键词： yttria-stabilized zirconia electrolyte, spark-plasma sintering, AC impedance.

Improvements on radiation-hardened performance of static induction transistor

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Science china(information Sciences) 2010年第5期53卷 1089-1096页

作者： WANG YongShun 1 , LUO XianLiang 1 , LI HaiRong 2 , WANG ZiTing 1 , WU Rong 1 , ZHANG CaiZhen 2 & LI SiYuan 2 1 School of electronic and information engineering, Lanzhou Jiaotong university, Lanzhou 730070, china 2 institute of Microelectronics, School of Physical Science and technology, Lanzhou university, Lanzhou 730000, china School of electronic and information engineering Lanzhou Jiaotong University Lanzhou China institute of Microelectronics School of Physical Science and Technology Lanzhou University Lanzhou China

The radiation-hardened performances of static induction transistor (SIT) have been studied in depth in this paper. The effects of radiation of electron beam on the I-V characteristics, carrier distribution and potential distribution in the channel of SIT have been represented. A large number of electron-hole pairs are generated in the depletion region of reversely biased gate-channel PN junction. The radiation-generated electrons drift towards the drain region at high positive potential, while generated holes flow into gate region biased to the lowest potential. With the accumulation of holes in gate region, the gate potential is boosted, resulting in a decrease in the height of potential barrier in channel, and an increase in drain current. I-V characteristics of SIT in the presence of radiation have been theoretically derived, and compared with experimental results. With the increase in thickness of epitaxial layer, the radiation-hardened capability of SIT is continuously improved until the optimum thickness of 26 μm is reached. The optimum matching relationship among geometric, material and technological parameters has been represented to acquire excellent radiation-hardened performances of SIT.

关键词： static induction transistor radiation-resistant potential barrier electron beam radiationgenerated carriers

Wavefront reconstruction algorithm for wavefront sensing based on binary aberration modes

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Chinese Physics B 2017年第5期26卷 153-159页

作者：庞博清王帅程涛孔庆峰文良华杨平 Key Laboratory on Adaptive Optics Chinese Academy of Sciences Chengdu 610209 China university of Chinese Academy of Sciences Beijing 100049 China The institute of Optics and electronics Chinese Academy of Sciences Chengdu 610209 China School of Optoelectronic information University of Electronic Science and Technology of China Chengdu 610209 China School of Physics and electronic engineering Yibin University Yibin 644000 China

We propose a new algorithm for wavefront sensing based on binary intensity modulation. The algorithm is based on the fact that a wavefront can be expended with a series of orthogonal and binary functions, the Walsh series. We use a spatial light modulator（SLM） to produce different binary-intensity-modulation patterns which are the simple linear transformation of the Walsh series. The optical fields under different binary-intensity-modulation patterns are detected with a *** relationships between the incident wavefront modulated with the patterns and their optical fields are built to determinate the coefficients of the Walsh series. More detailed and strict relationship equations are established with the algorithm by adding new modulation patterns according to the properties of the Walsh functions. An exact value can be acquired by solving the equations. Finally, with the help of phase unwrapping and smoothing, the wavefront can be reconstructed. The advantage of the algorithm is providing an analytical solution for the coefficients of the Walsh series to reconstruct the wavefront. The simulation experiments are presented and the effectiveness of the algorithm is demonstrated.

关键词： wavefront aberration Walsh modulated reconstructed optics incident smoothing Zernike modulator

A Modified Root-MUSIC Algorithm for Signal DOA Estimation

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Journal of Systems engineering and electronics 1999年第4期10卷 42-47页

作者： He Zishu Li Yong & Xiang Jingcheng(institute of electronic engineering, university of electronic Science & technology,Chengdu 610054, P. R. china) institute of electronic engineering University of Electronic Science & Technology Chengdu 610054 P. R. China

This paper presents a modified Root-MUSIC algorithm by which the signal DOA estimation performance can be improved when the snapshot number is limited. The operation principlesof this algorithm are described in detail. It is also pointed out theoretically that this is equivalentto have increased the snapshot number and can make the DOA estimation better. Finally, somesimulating results to verify the theoretical analyses are presented.

关键词： Array signal processing Root-MUSIC algorithm Signal DOA estimation Eigendecomposition