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Acta Biochimica et Biophysica Sinica 2006年第7期 457-466页

作者： Kuan PENG~1 Ying LIN~1 Song-Ping LIANG~(1,2.) 1 college of life {2.,Peking {3.,Beijing 100871,china 2.college of life {2.,Hunan Normal {3.,Changsha 410081,china

Huwentoxin-XI purified from the Chinese bird spider Ornithoctonus huwena is a toxin withboth antiprotease activity and potassium channel blocking *** determine its solution structure,huwentoxin-Ⅺ was expressed in a yeast eukaryotic expression system and studied by ***15N labelingstrategy was used to facilitate the process of resonance *** nearly complete sequence-specificassignments of proton and nitrogen resonances were obtained by analyzing a series of two-dimensional（2.）and three-dimensional（3.）spectra,including DQF-COSY,TOCSY,NOESY,15N-1H HSQC,15N-1H HNHA,15N-1H HNHB,15N-1H TOCSY-HSQC and15N-1H NOESY-HSQC *** structure analysis ofhuwentoxin-Ⅺ showed that it mainly contains an N-terminal 3.0-helix from Thr3.to Arg5 and a C-terminalα-helix from Gln45 to Cys52.plus a triple-stranded antiparallel β-sheet of Glul 8-Asn2.0}Thr2.-Ile3. *** studies provide a solid basis for the final structure determination of huwentoxin-Ⅺ.

关键词： huwentoxin-XI toxin nuclear magnetic resonance 15N labeling sequence-specific assignment

Complete quantum circuit of Haar wavelet based MRA

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Chinese science Bulletin 2005年第16期50卷 1796-1798页

作者： HE Yuguo1,2.& SUN Jigui1,3.1. college of Computer {2. and Technology, Jilin university, Changchun 13.012. {3. 2. Department of Computer {2. and Engineering, Beijing Institute of Technology, Beijing 100081, {3. 3. Key Laboratory of Computation and Knowledge Engineering of Min-istry of Education, Jilin university, Changchun 13.012. {3. college of Computer science and Technology Jilin University Changchun 130012 China

Wavelet analysis has applications in many ar- eas, such as signal analysis and image processing. We pro- pose a method for generating the complete circuit of Haar wavelet based MRA by factoring butterfly matrices and con- ditional perfect shuffle permutation matrices. The factoriza- tion of butterfly matrices is the essential part of the design. As a result, it is the key point to obtain the circuits of I 2. ⊕ W ⊕ I 2. ? 2. ?2. In this paper, we use a simple means to de- velop quantum circuits for this kind of matrices. Similarly, the conditional permutation matrix is implemented entirely, combined with the scheme of Fijany and Williams. The cir- cuits and the ideas adopted in the design are simple and in- telligible.

关键词：量子计算量子算法量子电路 Haar微波 MRA

Thermal-stress Simulation of Direct-chill Casting of AZ3. Magnesium Alloy Billets

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Journal of Wuhan university of Technology(Materials science) 2009年第3期24卷 376-382页

作者：胡红军 college of Materials science and Engineering Chongqing University National Engineering Research Center for Magnesium Alloys Chongqing University college of Material science and Engineering Chongqing University of Technology

Two-dimensional （2.） transient coupled finite element model was developed to compute the temperature and stress field in cast billets, so as to predict the defects of the I-type billets made from AZ3. magnesium alloy and find the causes and solutions for surface cracks and shrinkages during direct-chill （DC） casting process. Method of equivalent specific heat was used in the heat conduction equation. The boundary and initial conditions used for primary and secondary cooling were elucidated on the basis of the heat transfer during the solidification of the billet. The temperature and the thermal-stress fields were simulated with the thermal-structural coupled module of ANSYS software. The influences of casting parameters on the distributions of temperature and stress were studied, which helped optimize the parameters （at pouring temperature of 680 ℃, casting speed of 2.min/s, heat-transfer coefficient of the second cooling equals to 5 000 W/m^2.℃^-1）. The simulation results of thermal stress and strain fields reveal the formation mechanism of some casting defects, which is favourable for optimizing the casting parameters and obtain high quality billets. Some measures of controlling processes were taken to prevent the defects for direct-chill casting billets.

关键词： magnesium alloy direct-chill casting temperature and stress fields numerical simulation solidification model

Denitrification in Chongming east tidal flat sediment, Yangtze estuary, china

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science china Earth sciences 2006年第10期49卷 1090-1097页

作者： WANG Dongqi1,2. CHEN Zhenlou1,3. XU Shiyuan1,2. HU Lingzhen1 & WANG Jun1,2.1. college of Resources & Environment, East {2. Normal university, Shanghai 2.0062. {2. 2. State Key Laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics, East {2. Normal university, Shanghai 2.0062. {2. 3. Key Laboratory of Geographical Information science of Ministry of Education,East {2. Normal university,Shanghai 2.0062. {2. college of Resources & Environment East China Normal University Shanghai China State Key Laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics East China Normal University Shanghai China Key Laboratory of Geographical Information science of Ministry of Education East China Normal University Shanghai China

From July 2.03.to July 2.04, samples were collected on Chongming Island east tidal flat every two months. The research showed that the nitrous oxide (N2.) production rate was very low in the water, Chongming east tidal flat (CM) sediment was the N2. source of the water. Sediment N2. natural production rate was between -0.08 and 1.74 μmolN·m-2.h-1. N2. natural production rate was higher in the summer. The difference of the N2. natural production rate in the different tidal flats, the correlation between the N2. natural production rate and the denitrification rate, and those with the temperature and DO indicate that middle tidal flat sediment denitrification was the main process of the N2. production, while in the low tidal flat sediment, the production of the N2. came from several processes of the nitrogen cycling. Tidal flat sediment denitrification reaction was stronger in summer and winter but relatively lower in the late autumn and early spring. Seasonal change of the sediment denitrification rate was wide, from 1.12.to 3..3. μmolN·m-2.h-1. Temperature, DO and the coactions of them had the prominent effect on the tidal flat sediment denitrification.

关键词： Yangtze estuary, tidal flat sediment, denitrification, nitrous oxide, effect factor.

On the Symmetry Classes of Functions

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Wuhan university Journal of Natural sciences 2005年第5期10卷 813-816页

作者： ZHU Ping~1,2. FAN Yun~3.1. School of Mathematics and Statistics, Wuhan university, Wuhan 43.072. Hubei, china 2. School of science, Beijing university of Posts and Telecommunications, Beijing 100876, china 3. School of Mathematics and Statistics, Huazhong Normal university, Wuhan 43.079, Hubei, china School of Mathematics and Statistics Wuhan University Wuhan Hubei China School of science Beijing University of Posts and Telecommunications Beijing China School of Mathematics and Statistics Huazhong Normal University Wuhan Hubei China

Let R be an integral domain of characteristic zero such that the corresponding group rings have block decompositions. We first prove that the submodule consisting of all the R-valued ξi-symmetric functions of several variables is a symmetry class, where ξi is any block character. Then we present a relationship among certain operators introduced for block character. Then we present a relationship among certain operators introduced for block characters. As a consequence, we obtain a decomposition of an arbitrary R-valued function of several variables. Finally, we describe the symmetry property of such summands and determine all the symmetry classes.

关键词： symmetry class strict symmetry class blockcharacter ξi-symmetric function block idempotent

Analysis for twinning and slip in face-centered cubic crystals under axisymmetric co-deformation

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science china(Technological sciences) 2006年第5期49卷 521-536页

作者： CHEN Zhiyong1,2. CAI Hongnian1, ZHANG Xinming2. WANG Fuchi1 & TAN Chengwen1,3.1. School of Material science and Engineering, Beijing Institute of Technology, Beijing 100081, {2. 2. School of Material science and Engineering, Central South {3., Changsha 410083. {2. 3. School of Material science and Engineering, Beijing {3. of Aeronautics and Astronautics, Beijing 100083. {2. School of Material science and Engineering Beijing Institute of Technology School of Material science and Engineering Central South University

The maximum work principle of Bishop-Hill was developed to analyze the axisymmetric co-deformation in face-centered cubic crystals (f.c.c.) for twinning on {111} 112.and slip on {111} 110 systems. The influence of ξ , the ratio of critical re- solved shear stress for twinning to slip, on the yield stress states and corresponding active slip or/and twinning systems for orientations in the standard stereographic triangle of cubic crystal was investigated systematically. The Taylor factors and the anisotropy of yield strength for three important orientations [100], [110] and [111] in orientation space were analyzed. It is found that the yield strength asymmetry for the case of axisymmetric de- formation of tension and compression can be explained based on the microscopic theory of crystal plasticity. The concept of orientation factor for twinning ability was proposed and the deformation mechanism map in the orientation space was established for the case of axisymmetric deformation. The deformation texture formation and development of f.c.c. crystals with low stacking fault energy for axisymmetric tension can be explained qualita- tively on the basis of analyzed results.

关键词： twinning slip face-centered cubic crystals axisymmetric co-deformation Bishop-Hill maximum work principle yield strength anisotropy

Online uniform machine covering with the known largest size

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Progress in Natural science:Materials International 2007年第11期17卷 1271-1278页

作者： Cao Shunjuan1,2.and Tan Zhiyi1,3.1. Department of Mathematics, Zhejiang university, Hangzhou 3.002., china 2. Department of Mathematics, Zhejiang Forestry university, Hangzhou 3.13.0, china 3. State Key Laboratory of CAD & CG, Zhejiang university, Hangzhou 3.002., china) Department of Mathematics Zhejiang University Hangzhou 310027 China Department of Mathematics Zhejiang Forestry University Hangzhou 311300 China State Key Laboratory of CAD & CG Zhejiang University Hangzhou 310027 China

This paper investigates the semi-online scheduling problem with the known largest size on two uniform machines. The objective is to maximize the minimum machine completion time. Both lower bounds and algorithms are given. Algorithms are optimal for the majority values of s≥1, where s is the speed ratio of the two machines. The largest gap between the competitive ratio and the lower bound is about 0.064. Moreover, the overall competitive ratio 2.matches the overall lower bound.

关键词： scheduling and covering uniform machine design and analysis of algorithm online competitive ratio

Extraction of vegetation fraction information from CBERS images based on VBSI vegetation index in Kaixian county

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中国有色金属学会会刊：英文版 2011年第S3期21卷 712-716页

作者： GAO Zhi-fang1, NIU Hai-peng1, LIU Jin-ping2.1. college of Surveying and Land Information Engineering, henan Polytechnic {2., Jiaozuo 454000, {3. 2. college of Geographic sciences, Chongqing Normal {2., Chongqing 400047, {3. college of Surveying and Land Information Engineering Henan Polytechnic University Jiaozuo 454000 China college of Geographic sciences Chongqing Normal University Chongqing 400047 China

Based on the mixed pixel model, the vegetation fraction of Kaixian county, china, was extracted with three free CBERS images. VBSI vegetation index suitable for CBERS images constructed with FCD (forest canopy density) model principle was put forward by ITTO (International Tropical Timber Organization) was used, considering the underestimation of vegetation fraction using NDVI in low mountain-hill region influenced by soils and shadows. And vegetation fraction was divided into five categories from low to high in order to study the special variation of vegetation cover. The results show that the vegetation cover of the region is overall good, with an average of 50%. The area of vegetation fraction below 3.% accounts for 11.7% of the entire studied area, mainly concentrates in central eastern Kaixian county, where is the major development zone of cities and towns; that between 3.% and 60% accounts for 62.; and that higher than 60% accounts for 2.%, and mostly locates in northern middle-mountain area.

关键词： VBSI vegetation index mixed pixel model FCD model CBERS

A low frequency piezoelectric power harvester using a spiral-shaped bimorph

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science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 649-659页

作者： HU Yuantai1,2.HU Hongping2.& YANG Jiashi3.1. Institute of Mechanics and Sensing Technology,Central South university,Changsha 410083.china 2. Department of Mechanics,Huazhong university of {3. and Technology,Wuhan 43.074,china 3. Department of Engineering Mechanics,university of Nebraska,Lincoln,NE 68588-052.,USA Institute of Mechanics and Sensing Technology Central South University Changsha 410083 China

We propose a spiral-shaped piezoelectric bimorph power harvester operating with coupled flexural and extensional vibration modes for applications to low frequency energy sources. A theoretical analysis is performed and the computational results show that the spiral structure has relatively low operating frequency compared to beam power harvesters of the same size. It is found that to optimize the performance of a piezoelectric spiral-shaped harvester careful design is needed.

关键词： spiral-shaped bimorph,piezoelectric harvester,power density.

Electron microscopy study of the sakhaite from endogenous borate deposit in Hunan, china

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science china Earth sciences 2004年第3期47卷 232-238页

作者： LIU Xiangwen1,2. YANG Guangming2. ZOU Huamin3. QU Jing1 & ZHAO Wenxia4 1. Graduate School, china {2. of Geosciences, Wuhan 43.074, china 2. Test Center, china {2. of Geosciences, Wuhan 43.074, china 3. Physics and Technology {12., Wuhan {2., Wuhan 43.072. china 4. Test Center, Zhongshan {2., Guangzhou 5102.5, china Graduate School China University of Geosciences Wuhan 430074 China Test Center China University of Geosciences Wuhan 430074 China Physics and Technology college Wuhan University Wuhan 430072 China Test Center Zhongshan University Guangzhou 510275 China

Sakhaite specimens from an endogenous borate deposit in Hunan Province, china have been studied in detail by means of transmission electron microscopy (TEM). The selected area electron diffraction (SAED) patterns obtained with different crystal zone axes show that the crystal system is cubic, with a = 1.463.nm. The convergent beam electron diffraction (CBED) patterns indicate that the point group and space group of sakhaite is m3. and Fd3., respec-tively. The space group of synthetic sakhaite determined by Chichagov (1974) is F413.. The possible reasons why the space groups of the natural and the synthetic sakhaites are different are discussed.

关键词： sakhaite, space group, convergent beam electron diffraction (CBED).