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HSP70分子伴侣系统研究进展

生物化学与生物物理进展 1999年第6期26卷 554-558页

作者：张玉秀柴团耀中国科学技术大学研究生院生物部北京100039

综述了ＨＳＰ７０分子伴侣系统的晶体结构、功能及作用机理方面的研究进展．ＨＳＰ７０分子伴侣能够帮助细胞内新生蛋白的折叠和跨膜运输、蛋白质多聚体结构的装配和解装配，并能在胁迫下维持蛋白质的特殊构象，防止未折叠的蛋白质... 详细信息

综述了ＨＳＰ７０分子伴侣系统的晶体结构、功能及作用机理方面的研究进展．ＨＳＰ７０分子伴侣能够帮助细胞内新生蛋白的折叠和跨膜运输、蛋白质多聚体结构的装配和解装配，并能在胁迫下维持蛋白质的特殊构象，防止未折叠的蛋白质变性和使聚集的蛋白质溶解复性．所有这些活性均依赖于ＡＴＰ调节的ＨＳＰ７０与底物蛋白中的疏水片段的相互作用．

关键词： HSP70 分子伴侣结构功能蛋白质 ATP

Composite Cathode Bi_(1.14.Sr_(0.4.)O_(2.14.-Ag for Intermediate-temperature Solid Oxide Fuel Cells

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Journal of Wuhan University of Technology(Materials science) 2008年第3期23卷 350-353页

作者：高展张萍 Faculty of Material science and Chemical engineering China University of Geosciences

Composites consisting of strontium stabilized bismuth oxide （Bi1.14.r0.4.O2.14. SSB） and silver were investigated as cathodes for intermediate-temperature solid oxide fuel cells with doped ceria electrolyte. There were no chemical reactions between the two components. The microstructure of the interfaces between composite cathodes and Ce0.8Sm0.2O1.9 （SDC） electrolytes was examined by scanning electron microscopy （SEM）. Impedance spectroscopy measurements show that the performance of cathode fired at 700 ℃ is the best. When the content of Ag2O is 70 wt%, polarization resistance values for the SSB-Ag cathodes are as low as 0.2 Ωcm^2 at 700℃ and 0.29 Ωcm^2 at 650℃. These results are much smaller than some of other reported composite cathodes on doped ceria electrolyte and indicate that SSB-Ag composite is a potential cathode material for intermediate temperature SOFCs.

关键词： solid oxide fuel cells (SOFCs) composite cathode strontium stabilized bismuth oxide (SSB) samaria doped ceria (SDC)

A class of binary cyclic codes with five weights

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science china Mathematics 2010年第12期53卷 3279-3286页

作者： LI ChunLei 1 , ZENG XiangYong 1, & HU Lei 2 1 Faculty of Mathematics and Computer science, Hubei University, Wuhan 4.0062, china 2 The State Key Laboratory of Information Security, Graduate School of Chinese Academy of sciences, beijing 10004., china 1. Faculty of Mathematics and Computer science Hubei University Wuhan 430062 China2. The State Key Laboratory of Information Security Graduate School of Chinese Academy of Sciences Beijing 100049 China

In this paper, the dual code of the binary cyclic code of length 2 n-1 with three zeros α, α t 1 and α t 2 is proven to have five nonzero Hamming weights in the case that n 4.is even and t1 = 2 n/2 + 1, t2 = 2 n-1-2 n/2+1 + 1 or 2 n/2 + 3, where α is a primitive element of the finite field F 2 n . The dual code is a divisible code of level n/2+1, and its weight distribution is also completely determined. When n = 4. the dual code satisfies Ward's bound.

关键词： cyclic code Niho exponent exponential sum Pless power moment identity weight distribution

Institutional preparation for relaxation of control over the upstream petroleum industry in china

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Petroleum science 2009年第1期6卷 98-103页

作者： Chen Shouhai Zhang Baosheng School of Business Administration China University of Petroleum Beijing 102249 China

Relaxation of control over the upstream business of the petroleum industry in china is discussed. The authors suggest that a basic institutional preparation should be made before relaxing control over the upstream business, and that the institutional preparation includes at least four parts： 1） setting up the admission standards, 2） perfecting the management system of mining rights, 3） reforming the royalty and taxation system for oil and gas resources, and 4. improving the supervision and management system. Stressing the institutional preparation before relaxation of control does not mean that china could not relax control over the upstream business until the management systems are perfected, but the authors suggest that china could establish a necessary system for relaxation of control and to improve it with future practice.

关键词： Petroleum industry upstream business relaxation of control institutional preparation

Relationship between precipitation and the infiltration depth over the middle and lower reaches of the Yellow River and Yangtze-Huaihe River Valley

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Progress in Natural science:Materials International 2008年第9期18卷 1123-1128页

作者： Zhixin Hao a, Jingyun Zheng a, Quansheng Gea,, Xifeng Guoa,b a Institute of Geographical sciences and Natural Resources Research, Chinese Academy of sciences, 11A, Datun Road Anwai, Chaoyang District, beijing 100101, china b Graduate University of Chinese Academy of sciences, beijing 10004., china Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences 11A Datun Road Anwai Chaoyang District Beijing 100101 China Graduate University of Chinese Academy of sciences Beijing 100049 China

The purpose of the paper is to extract and make the best use of rainfall information contained in the Chinese historical archives of Qing Dynasty, and reconstruct the precipitation series during *** study followed the Yu-Fen-Cun (rainfall infiltration depth) observation method in Qing Dynasty, to conduct soil infiltration experiment under the natural rainfall conditions during *** related parameters, such as precipitation, intensity, initial soil moisture content and infiltration depth have been measured at 10 stations (east of 105°E, 30°-4.°N) with representative climatic conditions and soil physical texture in the middle and lower reaches of the Yellow River and Yangtze-Huaihe River *** statistical results indicate that precipitation is the primary infiuencing factor to infiltration depth and is positively correlated with the infiltration ***, the efiects of every factor on infiltration depth are significantly difierent between the middle and lower reaches of the Yellow River and Yangtze-Huaihe River ***, the relationship equations of precipitation and infiltration depth are established for each site, most of which can pass over 60% of the variance explanations and provide quantitative models to reconstruct the precipitation series using Yu-Fen-Cun records in Qing Dynasty.

关键词： Middle and lower reaches of the Yellow River and Yangtze-Huaihe River Valley Precipitation Infiltration depth Yu-Fen-Cun Climate reconstruction

Microstructure and Resisting Thermal Shock Behaviors of TiC-Al_2O_3/Fe Functionally Graded Materials Prepared by SHS/PHIP

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Journal of Materials science & Technology 2001年第1期17卷 65-66页

作者： Weifang ZHANG Niansheng XI and Chunhu TAO Institute of Aeronautical Materials, beijing 100095, china Jiecai HAN and Shanyi DU Center for Composite Materials, Harbin Institute of Technology, Harbin 150001, china Inst Aeronaut Mat Beijing 100095 Peoples R China Harbin Inst Technol Ctr Composite Mat Harbin 150001 Peoples R China

The microstructure and composition of TiC-A12O3/Fe functionally graded materials (FGM) prepared by self-propagating high temperature synthesis and pseudo-hot isostatic pressing (SHS/ PHIP) were studied, and the resisting thermal shock behaviors were analyzed. The results show that TiC-A12O3/Fe FGM has graded composition distribution. No cross-section crack through the layers was found in the tests of thermal shock and fatigue.

关键词： functionally graded materials thermal shock graded composition high temperature

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基于时间区间的并行行为与并发事件逻辑

计算机工程 2002年第3期28卷 13-15,17页

作者：朱娟刘玉树北京理工大学计算机科学工程系北京100081

在基于时间区间的时态逻辑基础上,提出了一种处理主体并行行为与并发事件的逻辑理论框架。文章提出的逻辑系统将事件与动作置于同一个逻辑体系下,以时间区间为基础,深入分析了二者之间的关系,充分发挥了事件的作用,动作的描述得到简化... 详细信息

在基于时间区间的时态逻辑基础上,提出了一种处理主体并行行为与并发事件的逻辑理论框架。文章提出的逻辑系统将事件与动作置于同一个逻辑体系下,以时间区间为基础,深入分析了二者之间的关系,充分发挥了事件的作用,动作的描述得到简化。文章给出了逻辑系统的语法和语义描述,还提出了基于领域描述结构的并发事件冲突消解方法。

关键词：并行行为并发事件逻辑时间区间多主体系统神经网络

The formation process and cloud physical characteristics for a typical downburstproducing thunderstorm in beijing

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Chinese science Bulletin 2003年第S2期48卷 77-82页

作者： GUO Xueliang FU Danhong Institute of Almospherie Physics, Chinese Academy of sciences, beijing 100029. china Chinese Acad Sci Inst Atmospher Phys Beijing 100029 Peoples R China

The formation process and characteristics ofcloud physical structure of a severe thunderstorm accompa-nied with strong wind on 23 August, 2001 in beijing wasstudied using PSU/NCAR mesoscale model ( MM5) couplingwith a severe storm model with hail-bin microphysics. Theresults show that the specific topography and distributionfeatures of cold/warm current in the beijing region playedprominent roles in forming, developing and maintaining thesevere storm. Due to solar radiation heating and topographiclifting, the convective cells were easily formed when thewesterly airflow passed over high mountainous regions inbeijing. The warm and wet air entered the cloud from itsfrontage and enhanced the convection, and formed a largeamount of graupel/hail particles at the middle and upperportion of the clouds. The precipitation was primarilyformed due to melting of graupel/hail particles. The strongdowndraft was mainly produced by negative buoyancy dueto loading, melting of graupel/hail particles as well asevaporative cooling of rain water. The divergent airflow in-duced by the strong downdraft led to the disastrous burstwinds at the surface and also forced lifting of warm and wetairflow in the moving direction of the storm and formed newclouds that further promoted and maintained the storm de-velopment.

关键词： beijing region thunderstorm and disastrous wind cluud physical features.

Strict constraints on 2D primitive pairs for engineering symbol recognition:Theory and application

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science china(Information sciences) 2012年第5期55卷 1032-1041页

作者： LI Ting 1,2,QIU XianJie 1,HUANG He 1 & WANG ZhaoQi 1 1 Virtual Reality Laboratory,Institute of Computing Technology Chinese Academy of sciences,beijing 100190,china 2 Graduate University of Chinese Academy of sciences,beijing 10004.,china 1. Virtual Reality Laboratory Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Geometric constraints on the line-line pair,line-arc pair and arcarc pair are *** con-straints are able to encode the geometric relations between lines,arcs and circles.A geometric proof is presented to demonstrate that the constraints are stable under translation,rotation,uniform scaling or reflection of the primitive *** on the constraints,an algorithm for recognizing symbols in drawings is ***-perimental results show that,compared with three other methods,our method can distinguish more primitive pairs and has higher accuracy in engineering symbol recognition.

关键词： coordinated multi-point transmission multicell cooperation capacity analysis MIMO-OFDM power allocation frequency selective MIMO channel