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An overview of resistive random access memory devices

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Science Bulletin 2011年第Z2期 3072-3078页

作者： LI YingTao 1,2., LONG ShiBing 2., LIU Qi 2., Lü HangBing 2., LIU Su 1 & LIU Ming 2. 1 School of Physical Science and Technology, Lanzhou University, Lanzhou 73.000, china 2.Laboratory of Nano-Fabrication and Novel Device Integration, institute of Microelectronics,{2., beijing 10002., china

With recent progress in material science, resistive random access memory (RRAM) devices have attracted interest for nonvolatile, low-power, nondestructive readout, and high-density memories. Relevant performance parameters of RRAM devices include operating voltage, operation speed, resistance ratio, endurance, retention time, device yield, and multilevel storage. Numerous resistive-switching mechanisms, such as conductive filament, space-charge-limited conduction, trap charging and discharging, Schottky Emission, and Pool-Frenkel emission, have been proposed to explain the resistive switching of RRAM devices. In addition to a discussion of these mechanisms, the effects of electrode materials, doped oxide materials, and different configuration devices on the resistive-switching characteristics in nonvolatile memory applications, are reviewed. Finally, suggestions for future research, as well as the challenges awaiting RRAM devices, are given.

关键词： resistive random access memory resistive switching performance parameters

Moment tensor analysis of the acoustic emission source in the rock damage process

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Progress in Natural Science:Materials International 2005年第7期15卷 609-613页

作者： YU Huaizhong, ZHU Qingyong, YIN Xiangchu and WANG Yucang ( State Key Laboratory of Earthquake Dynamics, institute of Geology, china Earthquake Administration, {2. 10002., china State Key Laboratory of Nonlinear Mechanics, institute of Mechanics, chinese academy of sciences, {2. 100080, china School of Mathematics and Computational Science, Zhongshan University, Guangzhou 5102.5, china Center for Analysis and Prediction, china Seismological Bureau, {2. 10003., china Quakes, Department of Earth Science, University of Queensland, Brishbane, Austrialia) State Key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China School of Mathematics and Computational Science Zhongshan University Guangzhou 510275 China Center for Analysis and Prediction China Seismological Bureau Beijing 100036 China Quakes Department of Earth Science University of Queensland Brishbane Australia

To further investigate the mechanism of acoustic emission (AE) in the rock fracture experiment, moment tensor analysis was carried out. The AE sources characterized by crack sizes, orientations and fracture modes, are represented by a time-dependent moment tensor. Since the waveforms recorded by AE monitors correlate to the moment tensors, we prefer to select the P wave amplitude from the full-space Green's function of homogeneous and isotropic materials to determine the six independent components of the moment tensor. The moment tensor analysis was used to investigate the AE sources recorded in the experiment, and three types of micro-cracks were found, which are tensile mode, shear mode and mixture of the tensile and shear mode. In addition, the motion of micro-cracks was decided by eigenvectors of moment tensor. Results indicate that the moment tensor analysis may be used as a measurement to reflect the damage evolution of rock specimen.

关键词： moment tensor acoustic emission rock fracture.

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黄、东海冬季底层鱼类群落结构及多样性变化

水产学报 2004年第1期28卷 29-34页

作者：程济生俞连福农业部海洋渔业资源可持续利用重点开放实验室中国水产科学研究院东海水产研究所山东青岛 2.6071 中国水产科学研究院黄海水产研究所山东青岛 2.6071 上海 2.0090

根据1991年和2.00年冬季在黄海中南部和东海中北部海域进行的底拖网调查资料,对黄、东海底层鱼类群落的资源状况、重要种类的生态优势度与结构、多样性及其空间分布格局等方面的动态变化进行了分析。结果表明,生物量指数明显下降,个体... 详细信息

根据1991年和2.00年冬季在黄海中南部和东海中北部海域进行的底拖网调查资料,对黄、东海底层鱼类群落的资源状况、重要种类的生态优势度与结构、多样性及其空间分布格局等方面的动态变化进行了分析。结果表明,生物量指数明显下降,个体小型化使生物资源密度显著上升;重要种类成分发生演替,优势度有较大变化;物种丰富度指数(D)下降极其显著,Shannon-Wiener多样度指数(H′)也有所下降,但不显著。

关键词：底层鱼类群落结构多样性黄东海

Expression of Smad2.and Smad4 in rhesus monkey endometrium during the menstrual cycle and early pregnancy

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Progress in Natural Science:Materials International 2003年第8期 26-31+85-86页

作者： LIN Haiyan, WANG Hongmei, LI Qinglei, WANG Juan, ZHANG Xuan, LIU Donglin, LIU Huitu and ZHU Cheng (1. State Key Laboratory of Reproductive Biology, institute of Zoology, chinese academy of sciences, {2. 100080,{3. 2. Key Laboratory for Cell Proliferation and Regulation of Ministry of Education, institute of Cell Biology, College of Life sciences, {2. Nor-mal University, {2. 100875,{3.) State Key Laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing 100080 China Key Laboratory for Cell Proliferation and Regulation of Ministry of Education Institute of Cell Biology College of Life Sciences Beijing Normal University Beijing 100875 China

Expression of Smad2.and Smad4 mRNAs in the endometrium of rhesus monkey on Days 8, 2. and 2. of the normalmenstrual cycle and on Days 12. 18 and 2. of early pregnancy was detected using in situ hybridization. The results showed that Smad2.nd Smad4 mRNAs were mainly localized in luminal epithelium and glandular epithelium. The expression of Smad2.mRNA in glandularepithelium was sustained at moderate level on Days 8, 2. and 2. of the menstrual cycle, while the expression of Smad4 gradually in-creased with the menstrual cycle. Both Smad2.and Smad4 mRNAs in functionalis glandular epithelium were expressed at the highest lev-els on Day 12.of early pregnancy, while in basalis glandular epithelium the most abundant expression of both Smads occurred on Days 12.nd 18 of pregnancy. On Day 2., both Smads mRNAs were expressed at the lowest levels either in functionalis or in basalis. The datasuggest that the epithelium is the major compartment where TGF-βs/activins exert their biological effects via Smads, and tha

关键词： Smad rhesus monkey pregnancy menstrual cycle endometrium.

DESCRIPTION ON NEW SPECIES AND ZOOGEOGRAPHICAL ANALYSIS OF THE LAND MOLLUSKS FROM XISHUANGBANNA AND NEIGHBORING AREA, YUNNAN PROVINCE (GASTROPODA: PROSOBRANCHIA: ARCHAEOGASTROPDA, MESOGASTROPODA)

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Zoological Systematics 1998年第4期 356-359页

作者： CHEN De-Niu ZHANG Guo-Qing(institute of Zoology, the chinese academy of sciences, {2. 100080)

Study on the Total Synthesis of Hainanolide (V)-Oxidation of the Tricyclic Alkenes with Singlet Oxygen

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chinese Chemical Letters 1999年第8期10卷 657-658页

作者： Xiao Ming YU Lu Yan ZHANG Shi Zhi CHEN Liang HUANG (institute of Materia Medica, chinese {2. of Medical {3. and Peking Union Medical College, beijing 100050) institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China

Six tricyclic compounds containing C-3. C-4 double bonds were oxidized with singlet oxygen. Different regio-selectivity was found with regard to steric hinderence.

关键词： hainanolide singlet oxygen

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Effects of quorum sensing autoinducer degradation gene on virulence and biofilm formation of Pseudomonas aeruginosa

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Science china(Life sciences) 2007年第3期50卷 385-391页

作者： WANG Yao1, DAI Yue1,2. ZHANG Yong1,2. HU YangBo1,2. YANG BaoYu1 & CHEN ShiYun1 1 Wuhan {3. of Virology, chinese academy of sciences, Wuhan 43.071,{2. 2.Graduate University of chinese academy of sciences, beijing 100049,{2. Wuhan institute of Virology Chinese Academy of Sciences Wuhan 430071 China Wuhan institute of Virology Chinese Academy of Sciences Wuhan 430071 China Graduate University of chinese academy of sciences Beijing 100049 China

The aiiA gene from Bacillus thuringiensis was cloned into the Pseudomonas/E. coli shuttle vector and transformed into Pseudomonas aeruginosa strain PAO1. Western blotting showed that the AiiA protein was expressed in PAO1. After induction by IPTG for 6 h and 18 h, expression of the aiiA gene in PAO1 completely degraded the quorum sensing autoinducers N-acylhomoserine lactones (AHLs): N-oxododecanoyl-L-homoserine lactone (OdDHL) and N-butyryl-L-homoserine lactone (BHL). The re- duced amount of AHLs in PAO1 was also correlated with decreased expression and production of several virulence factors such as elastase and pyocyanin. AiiA expression also influenced bacterial swarming motility. Most importantly, our studies indicated that aiiA played significant roles in P. aeruginosa biofilm formation and dispersion, as observed by the differences of the biofilm formation on liquid and solid surfaces, and biofilm structures under a scanning electron microscope.

关键词： aiiA Effects of quorum sensing autoinducer degradation gene on virulence and biofilm formation of Pseudomonas aeruginosa gene

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Characterization of ATPase Activity of Recombinant Human Pif1

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Acta Biochimica et Biophysica Sinica 2006年第5期38卷 335-341页

作者： Yu HUANG Deng-Hong ZHANG Jin-Qiu ZHOU Max-Planck Junior Research Group at the State Key Laboratory of Molecular Biology,institute of Biochemistry and Cell Biology,Shanghai institutes for Biological {2.,{3. academy of {2.,Shanghai 2.003.,china Max-Planck Junior Research Group at the State Key Laboratory of Molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China

Saccharomyces cerevisiae Piflp helicase is the founding member of the Pifl subfamily that isconserved from yeast to *** potential human homolog of the yeast PIFI gene has been cloned fromthe cDNA library of the Hek2.3.cell ***,we described a purification procedure of glutathione S-transferase（GST）-fused N terminal truncated human Pifl protein（hPif1ΔN）from yeast and characterizedthe enzymatic kinetics of its ATP hydrolysis *** ATPase activity of human Pif1 is dependent ondivalent cation,such as Mg2.,Ca2.and single-stranded *** for ATP for the ATPase activity isapproximately 2.0 μ*** the ATPase activity is essential for hPifl’s helicase activity,these results willfacilitate the further investigation on hPif1.

关键词： Pifl helicase telomere telomerase ATPase

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2.糖尿病患者卒中预防及血糖管理专家共识

中华内科杂志 2024年第7期63卷 649-659页

作者：《2.糖尿病患者卒中预防及血糖管理专家共识》编写委员会陈莉明母义明不详天津医科大学朱宪彝纪念医院内分泌科天津300134 解放军总医院第一医学中心内分泌科北京100853

糖代谢异常与卒中关系密切,对卒中的发生、发展及预后均有不良影响。良好的血糖控制对改善卒中预后具有重要意义。部分降糖药物能够减少2.糖尿病患者卒中的发生及复发风险。2.糖尿病合并卒中患者应控制血压、血脂,合理应用抗血小板药... 详细信息

糖代谢异常与卒中关系密切,对卒中的发生、发展及预后均有不良影响。良好的血糖控制对改善卒中预后具有重要意义。部分降糖药物能够减少2.糖尿病患者卒中的发生及复发风险。2.糖尿病合并卒中患者应控制血压、血脂,合理应用抗血小板药物。共识专家组基于循证医学证据和临床实践,并经过多次讨论最终形成本共识,以期为临床提供参考。

关键词：糖尿病 2. 卒中预防血糖管理专家共识

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