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Morphologies of solid-liquid interface and surface steps during rapid growth of BaB_2._4 single crystals

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Science china(Physics,Mechanics & Astronomy) 2007年第4期50卷 539-545页

作者： PAN XiuHong, AI Fei, JIN WeiQing, LIU Yan & ZHANG Ying shanghai institute of Ceramics,{2., shanghai 200050, china shanghai institute of Ceramics Chinese Academy of Sciences Shanghai China

The evolution of solid-liquid interface during BBO single crystal growth was stud- ied by the differential interference microscopy. And the step morphology on (0001) surface of the as-grown crystal was observed by the atomic force microscopy as well. It was found that the transition from a flat solid-liquid interface to a skeletal shape will occur in case of rapid growth. However, AFM images of surface steps revealed morphology differences correlated with crystallographic directions. The steps advancing along direction form the step flow, whereas those steps propagating along direction shape into step segments. Measurements of step heights by AFM indicated that it is the high anisotropy of the dimension of growth unit and step bunching due to the enlargement of concentration difference along the surface that results in the anisotropy of step morphologies.

关键词： crystal growth morphological instability growth step AFM observation

Effects of A1 Additions on Microstructure and Mechanical Properties of MoSi_2

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Journal of Materials Science & Technology 1999年第6期15卷 578-580页

作者： Jianlin LI Dongliang JIANG and Shouhong TAN(shanghai institute of Ceramics,{2., 12.5 Dingxi Road, shanghai 200050, china) shanghai institute of Ceramics Chinese Academy of Sciences 1295 Dingxi Road Shanghai 200050 China

The effects of Al additions on the microstructure and mechanical properties of MoSi2.have been studied. With the A1 additions from 2.5 wt pct to 5 wt pct, the siliceous grain boundary phase in hot pressed samples was eliminated because of the formation of Al2.3 particles. It was shown that Al and SiO2.reacted at 860℃. During the reaction, A1 atoms were mainly transferred to Al2.3 particles, and to some extent, diffused into MoSi2.grains. Both the toughness and strength of Al containing composites exceeded those of pure MoSi2.material. Bending strength and fracture toughness reach the highest value of 350 MPa, 4.05 MPa.m1/2. respectively, at ambient temperature when Al addition was of 3.5 wt pct.

关键词： Figure MPa Effects of A1 Additions on Microstructure and Mechanical Properties of MoSi2

Serine racemase expression in mouse cerebral cortex after permanent focal cerebral ischemia

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Acta Pharmacologica Sinica 2004年第4期25卷 38-43页

作者： Li-zhenWANG, Xing-zu ZHU2.Department of Pharmacology, shanghai institute of Materia Medica, shanghai institutes for Biological sciences, chinese academy of sciences, shanghai 2.12.3, china Department of Pharmacology Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 上海 201203

AIM: To study the alterations of the expressions of serine racemase in C57BL/6 mouse brain after permanent focal cerebral ischemia. METHODS: The mRNA level and the protein level of serine racemase were assayed by semiquantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot, respectively. The amount of D-serine and L-serine were measured by HPLC. RESULTS: High levels of serine racemase were constitutively expressed in the normal cortex of mouse. At early stage after middle cerebral artery occlusion (MCAO), no significant change in expression of serine racemase was observed in temporoparietal cortex in ipsila- teral hemisphere. However, delayed transient decreases of serine racemase in both mRNA and protein levels were detected from d 6 to d 10 after ischemia. Correspondingly, D-serine concentration also declined in the ipsilateral cortex during this period when compared with the D-serine level in the contralateral cortex. CONCLUSION: Delayed decreases in serine racemase expression and D-serine level occurred in the temporoparietal cortex at the late stage after focal cerebral ischemia.

关键词： D-serine L-serine serine racemase inbred C57BL mice brain ischemia

Simulation on C/A codes and analysis of GPS/pseudolite signals acquisition

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Science china(Technological sciences) 2009年第5期52卷 1459-1462页

作者： ZHANG Lei shanghai institute of Technical Physics,{2. academy of sciences,shanghai 2.0083,china shanghai institute of Technical Physics Chinese Academy of Sciences Shanghai China

The global positioning system(GPS) is an extremely mature technique in the navigation and position-ing ***,there are still some limits in some aspects and for some special ***-cially,the performance of GPS needs to be improved with technological *** a GPS-like ground transmitter,the pseudolite provides a new research direction to achieve high positioning ac-curacy and *** this paper,we describe the core technologies of designing and simulation on the coarse acquisition codes in constructing the pseudolite *** the GPS/pseudolite integration system,the signal PRN 36 of the pseudolite and the GPS satellites signals are acquired in the modified receiver based on the computer software *** is shown that the pseudolite technology is ideally suited to augment the GPS alone and provide greater integrity,availability,and continuity of the navi-gation positioning system,especially for indoor use.

关键词： GPS pseudolite coarse acquisition(C/A) code acquisition

Conus Peptides-A Rich Pharmaceutical Treasure

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Acta Biochimica et Biophysica Sinica 2004年第11期36卷 713-723页

作者： Cheng-Zhong WANG and Cheng-Wu CHIinstitute of Biochemistry and Cell Biology, shanghai institute of Biological sciences, the chinese academy of sciences, shanghai 2.0031, china institute of Neuroscience, the chinese academy of sciences, shanghai 2.0031, china institute of Protein Research, Tongji University, shanghai 2.0092. china institute of Biochemistry and Cell Biology Shanghai Institute of Biological Sciences the Chinese Academy of SciencesShanghai 200031 China institute of Neuroscience the Chinese Academy of SciencesShanghai 200031 China institute of Protein Research Tongji UniversityShanghai 200092 China

Marine predatory cone snails (genus Conus) with over 500 species represent what is arguably the largest single genus of marine animals alive today. All Conus are venomous and utilize a complex mixture of Conus peptide... 详细信息

关键词： Conus peptide conotoxin neuropathic disorder pharmaceutical potency

In situ observation of NaBi(WO_4)_2.dendrite growth and the study on microstructure of solidification

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Science china(Physics,Mechanics & Astronomy) 2007年第4期50卷 525-530页

作者： AI Fei, HONG Yong, JIN WeiQing, LUO HaoSu, LIU Yan & PAN XiuHong shanghai institute of Ceramics,{2., shanghai 200050, china shanghai institute of Ceramics Chinese Academy of Sciences Shanghai China

The dendrite growth process of transparent NaBi(WO4)2.with small prandtl and high melting point was studied by using the in-situ observation system. According to the dynamic images and detailed information, there are two kinds of restriction effect on the dendrite growth, the competition between arms and branches and the convection in the melt. The dendrite growth rate was time dependent, and the rate of arm growth reached the maximum 5.8 mm/s in the diffusive-advective region and rapidly decreased in the diffusive-convective region. The growth rate of branch had the same change trends as the arm’s. Based on the EPMA-EDS data of solidifica- tion structure of quenched NaBi(WO4)2.melt, it was found that there were compo- nent differences from stoichiometric concentration in the melt near the interface during the growth process.

关键词： oxide dendrite in-situ observation solidification structure

Cloning and Analyzing of Xenopus Mespo Promoter in Retinoic Acid Regulated Mespo Expression

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 759-764页

作者： Jin-Hu WANG Xiao-Yan DING* institute of Biochemistry and Cell Biology,shanghai institutes for Biological sciences,chinese academy of sciences,Graduate School of the chinese academy of sciences,shanghai 2.0031,china institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China

During vertebrate embryogenesis,presomitic mesoderm cells enter a segmental program togenerate somite,a process termed ***,a member of the bHLH transcription factor family,plays important roles in this ***,how Mespo expression is regulated remains *** this question,we isolated a genomic DNA sequence containing 4317 bp of Mespo 5’ flanking regionin *** assays show that this upstream sequence has transcription *** assayshows that this genomic contig is sufficient to recapitulate the dynamic stage-and tissue-specific expressionpattern of endogenous Mespo from the gastrula to the tailbud *** further mapped a 32. bp DNAsequence responding to retinoic acid *** results shed light on how Mespo expression is regulated,and suggest that retinoic acid signaling pathways play roles in somitogenesis through regulating Mespo.

关键词： bHLH paraxial presomitic segmental tailbud Xenopus laevis

Preparation and Characterization of Sol-gel Derived CH_3SiO_(3/2.-SiO_2.Thick Film

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Journal of Materials Science & Technology 1998年第6期14卷 523-526页

作者： Bing CAO and Congshan ZHU(shanghai institute of Optics and Fine Mechanics,{2., shanghai 2.1800, china) shanghai institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China

A large size CH3SiO3/2.SiO2.self sustained film with the thickness ranging from 50 to 1000 μm was prepared through sol-gel method by adopting CH3Si(OC2.5)3 and Si(OC2.5) as *** this paper, the preparation processes of this thick film are discussed in detail and XRD technique was adopted for the identification of oligomer solution. Also, IR and AFM techniques were used to investigate the film structure and surface morphology

关键词： Preparation and Characterization of Sol-gel Derived CH3SiO MTES CH

Development of a complex scintillation proximity assay for highthroughput screening of PPAR7 modulators

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Acta Pharmacologica Sinica 2005年第3期26卷 339-344页

作者： Bin WU Jie GAO Ming-wei WANG~2.The National Center for Drug Screening,shanghai institute of Materia Medica,shanghai institutes for Biological sciences,chinese academy of sciences Graduate School of chinese academy of sciences,shanghai 2.12.3,china The National Center for Drug Screening Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of chinese academy of sciences Shanghai China

Aim:To develop a complex high-throughput screening （HTS） assay based onscintillation proximity assay （SPA） technology for identification of novel peroxi-some proliferator-activated receptor gamma （PPARγ） ***:Full-length PPARγ and retinoid X receptor alpha （RXRα）,biotinylated PPAR responseelement （PPRE）,[3H]BRL49653 and streptavidin-coated FlashPlate or microbeadwere used to develop an HTS assay based on SPA ***‘ABCDE’method was validated against conventional hydroxyapatite （HA） assay and ap-plied to large-scale screening of 16 000 synthetic compounds and natural ***:（1） IC50values of positive control compounds （BRL49653 andtroglitazone） obtained from the‘ABCDE’method and HA assay were compa-rable and consistent with those reported elsewhere;（2. Approximately 178compounds,showing more than 70% competitive inhibition on BRL49653 bind-ing to PPARγ,were identified initially by the‘ABCDE’method （microbead）;（3）Secondary screening using FlashPlate and cross-reactivity studies with RARα,β,γ and RXRα,β,γ confirmed that 12.compounds possessed specific PPARγ bind-ing properties including 2.with IC50values less than 0.5 μmol/L and novel chemi-cal ***:The‘ABCDE’method using either FlashPlate ormicrobead,is a highly efficient,automatable,and robust tool to screen potentialPPARγ modulators in HTS *** application may be expanded to othernuclear receptors that form heterodimers upon activation.

关键词： peroxisome proliferator-activated receptor gamma retinoid X receptor alpha scintillation proximity assay high-throughput screening