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Study on Single-fiber Pull-out Method for Evaluating interfacial Strength.in CFRP

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high Technology Letters 1995年第1期1卷 105-108页

作者： Yudong, h. zh.qian, zh. Lixun, L. Qiwei, L. harbin inst of Technology Harbin China

Single-fiber pull-out testing (SFPOT) methods are frequently used to evaluate the interfacial adhesion between fiber and matrix in composite materials. To make such pull-out measurements, however, the length of embedded fiber must be small enough so that the fiber does not break before it is pulled freely. This is difficult to achieve by conventional methods with fibers of small diameter, such as the carbon fibers. in this paper, a fiber pull-out experiment is described. Specialized apparatus in our laboratory, as well as this tech.ique for sample preparation are discussed in detail. The interfacial shear strength of carbon fiber/resin matrix composites is analyzed quantitatively by using the finite-element method. The SFPOT system has been proved to be an available means for the study of interfacial properties for carbon fiber/resin matrix composites.

关键词： Carbon fiber Composite materials interfacial shear strength Single-fiber pull-out

REACTiON OF 3,7-DiNiTRODiBENZOBROMOLiUM BiSULFATE WiThSOME NUCLEOPhiLES

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Chinese Chemical Letters 1996年第6期7卷 505-506页

作者： hou, ZJ Zh.ng, h Zh.ng, zh LANzh.U UNiV INST ORGAN CHEMLANZHOU 730000PEOPLES R CHINA LANzh.U UNiV STATE KEY LAB APPL ORGAN CHEMLANZHOU 730000PEOPLES R CHINA

Reaction of 3,7-dinitrodibenzobromolium bisulfate with some nucleophiles were studied. Primary products of reactions ore 2-bromo-2'-Nu-4-4'-dinitro-biphenyls.

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Selective De-O-acetylation in TCP-containing Carbohydrate Structures with Magnesium Methoxide

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Chinese Chemical Letters 2000年第11期11卷 941-944页

作者： Qin, zh.Li, h Cai, MS Li, ZJ Beijing Med Univ Sch Pharmaceut Sci Dept Bioorgan Chem Beijing 100083 Peoples R China

Magnesium methoxide can be used for TCP-containing substrates to remove acetyl group successfully while leaving the TCP-group virtually intact.

关键词： OCh TCP De

The W-11-4A Platform Comprehensive Strength Monitoring System

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China Ocean Engineering 1998年第2期13卷 135-146页

作者： Shen, zh.Li, h Xue, Yi Chen, JC zh.o, Q Chinese Acad Sci Inst Mech Beijing 100080 Peoples R China Louisiana Tech Univ Appl & Computat Anal & Modeling Program Ruston LA 71272 USA Acad Sinica S China Sea Inst Oceanol Guangzhou 510301 Peoples R China

A comprehensive strength monitoring system used on a fixed jacket platform is presented in this paper. The long-term monitoring of W-11-4A platform achieved. Structural responses (strain and acceleration) at selected locations, as well as associated environmental parameters, have been obtained. The emphasis of the paper is placed on the system design, and the instrumentation and operation methodology employed in the monitoring of the structural responses. The performance of the system and the characteristic results obtained during its 13-month operation are also summarized.

关键词： monitoring tech.iques comprehensive strength monitoring structural responses waterproof strain transducers underwater instrumentation tech.iques

Sensitive analysis of amino acids in injection liquor by reversed-phase hPLC

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Chinese Journal of Chemistry 1995年第2期13卷 163-168页

作者： Sh.ng, zh.YU, YN GUO, W JiAng, h zh.U, LM ChiNESE ACAD SCi DALIAN INST CHEM PHYSDALIAN 116012PEOPLES R CHINA

A convenient derivatization method of amino acids with 1-fluoro-2,4-dinitrobezene as reaction reagent and a separation system were described. The derivative amino acids were separated on a specific chemically bonded phase column with a simple linear gradient elution consisting of aqueous buffer and methanol. The eluate was detected by common ultraviolet absorption detector at 360 nm. The detection limits of amino acids were as low as 10 picomole. This method has been successfully applied to assay amino acid injection liquor used in hospital. it has good reproducibility and precision. The procedures avoid the requirements of particular derivative equipment and analyzer employed in conventional amino acid analysis.

关键词： AMiNO ACiDS PRECOLUMN DERiVATiZATiON REVERSED PhASE SEPARATiON UV ABSORPTiON DETERMiNATiON

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中国城镇居民收入和消费的协整分析

消费经济 2005年第2期21卷 16-19页

作者：张继海臧旭恒山东大学经济学院山东济南250100

本文利用误差修正模型对中国城镇居民收入和消费进行协整分析。通过协整分析实证分析了中国城镇居民消费和收入之间的短期波动和长期均衡关系。实证分析的结果表明中国城镇居民家庭实际收入和实际消费之间存在长期的协整关系,当期收入... 详细信息

本文利用误差修正模型对中国城镇居民收入和消费进行协整分析。通过协整分析实证分析了中国城镇居民消费和收入之间的短期波动和长期均衡关系。实证分析的结果表明中国城镇居民家庭实际收入和实际消费之间存在长期的协整关系,当期收入和长期均衡对居民消费都具有较强的制约作用。在长期中,收入增长是制约居民消费增长的重要因素。

关键词：中国城镇居民收入消费需求消费者消费水平

SUBSTRUCTURE PRECONDiTiONERS FOR NONCONFORMing PLATE ELEMENTS

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Journal of Computational Mathematics 1998年第4期16卷 289-304页

作者： Shi, ZC Xie, zh Chinese Acad Sci ICMSEC State Key Lab Sci & Engn Comp Beijing 100080 Peoples R China Chinese Acad Sci Inst Atmospher Phys LASG Beijing 100080 Peoples R China

in this paper, we consider the problem of solving finite element equations of biharmonic Dirichlet problems. We divide the given domain into non-overlapping subdomains, construct a preconditioner for Morley element by substructuring on the basis of a function decomposition for discrete biharmonic functions. The function decomposition is introduced by partitioning these finite element functions into the low and high frequency components through the intergrid transfer operators between coarse mesh and fine mesh, and the conforming interpolation operators. The method leads to a preconditioned system with the condition number bounded by C(1 + log(2) h/h) in the case with.interior cross points, and by C in the case without interior cross points, where h.is the subdomain size and h.is the mesh size. These tech.iques are applicable to other nonconforming elements and are well suited to a parallel computation.

关键词： substructure preconditioner biharmonic equation nonconforming plate element

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从消费税的设置目的谈我国消费税改革

消费经济 2005年第2期21卷 31-33页

作者：何志静暨南大学经济学院广东广州510632

我国现行的消费税是1994年税改设置的税种,设置目的是为调节产品结构、引导消费方向、保证国家收入。经过十多年的经济发展,我国的现行消费税制在一些方面已经与其设置目的不相符,这就要求我们对现行的消费税制进行改革,更好的发挥消费... 详细信息

我国现行的消费税是1994年税改设置的税种,设置目的是为调节产品结构、引导消费方向、保证国家收入。经过十多年的经济发展,我国的现行消费税制在一些方面已经与其设置目的不相符,这就要求我们对现行的消费税制进行改革,更好的发挥消费税的特殊调节作用。

关键词：消费税设置目的改革中国课税范围税率

Serum deprivation enhances DNA synthesis of human hepatoma SMMC-7721 cells

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World Journal of Gastroenterology 1998年第2期4卷 29-32页

作者： Jiang, SM Xu, zh Shandong Normal Univ Dept Biol Provincial Key Lab Anim Stress Jinan 250014 Shandong Provin Peoples R China

AiM To determine the relationship between serum deprivation or serum levels and cell proliferation of human hepatoma SMMC 7721 cells. METhODS human hepatoma SMMC 7721 cells were grown in RPMi 1640 supplemented with 10% fetal calf (FCS) in 5% CO 2 incubator at 37℃ for 24h , and culture media were replaced to serum free or different serum FCS levels (2 5%, 5%, 10%, 20% and 25%). Six h, 12h , 18h and 24h after the culture, the cells were incorporated TdR for 4h . At last TdR incorporation was detected with liquid scintillation counting. RESULTS DNA synthesis of SMMC 7721 cells could be sharply stimulated by short time (6h) serum deprivation (the cpm value of 3h TdR incorporation of cells in serum free was 39 32 fold higher than cells in 25% serum), and the incorporation of 3h TdR was negatively related to the serum levels. Longer time serum starvation ( 12h , 18h and 24h ) also greatly stimulated DNA synthesis, although the cpm value of 3h TdR incroporation was less than that in 6h serum deprivation. Morphology of cells cultured in different serum levels also showed significant difference. CONCLUSiONS Compared with other cell lines such as BEL7404 and Swiss 3T3, human hepatoma SMMC 7721 cells had different response to the serum deprivation. Short time serum deprivation could greatly stimulate DNA synthesis of human hepatoma SMMC 7721 cells. Precautions must be given to the ch.nges of serum levels for the detection of growth factors and drugs using SMMC 7721 cells as a model.

关键词： liver neoplasms carcinoma, hepatocellular DNA, neoplasm/biosynthesis SMMC 7721 tumor cell, cultured cell proliferation growth factors