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Research on the Characters of the Cutting Force in Vibration Cutting Particle Reinforced Metal Matrix Composites SiC_p/Al

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厦门大学学报（自然科学版） 2002年第S1期41卷 74-75页

作者： LIU Chuan-shao 1, ZHAO Bo 1,2. GAO Guo-fu 1, JIAO F eng 1 (1. Department of Mechanical Engineering, Jiaozuo institute of Techno logy, Henan 454000, china 2. institute of Mechanical Engineering, Shanghai Jiaotong University, Shanghai 2.0030, china)

In this paper, turning experiments of machining particle reinforced metal matri x composites(PRMMCs) SiC p/Al with PCD tools have been carried out. The cutting force characteristics in ultrasonic vibration turning compared with that in com mon turning were studied. Through the single factor experiments and multiple fac tor orthogonal experiments, the influences of three kinds of cutting conditions such as cutting velocity, amount of feed and cutting depth on cutting force were analyzed in detail. Meanwhile, according to the experimental data, the empirica l formula of main cutting force in ultrasonic vibration turning was conclude d. According to the test results, the cutting force is direct proportion to cutt ing depth basically according to the relation between cutting force and other fa ctors, which is similar to that of common cutting, so is the feed rate, but the influence is not so big. The influence of cutting speed is larger than that of f eed rate on cutting force because the efficient cutting time increases in vibrat ion cycle with the increase of cutting speed, which causes cutting force to incr ease. The research results indicate: (1) Ultrasonic vibration turning possesses much lower main cutting force than that in common turning when adopting smaller cutting parameters. If using larger cutting parameters, the difference will inco nspicuous. (2. There are remarkable differences of cutting force-cutting veloci ty characteristics in ultrasonic vibration turning from that in common turning m ainly because built-up edge does not emerge in ultrasonic turning unlike common turning in corresponding velocity range. (3) In ultrasonic vibration cutting, t he influence of cutting velocity on cutting force is most obvious among thre e cutting parameters and the influence of feed is smallest. So adopting lower cu tting velocity and larger cutting depth not only can reduce cutting force effect ively but also can ensure cutting efficiency. (4) The conclusions are usefu

关键词： composite SiC p/Al PCD tool ultrasonic vibrati on turning cutting force

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SYNTHESIS　OF　POLYSUBSTITUTED　AROMATIC　COMPOUNDS　***　DIELS-ALDER　REACTION　OF　PHENYLSELENO　SUBSTITUTED　DIENES　WITH　DIMETHYL　ACETYLENEDICARBOXYLATE

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chinese Chemical Letters 1995年第9期6卷 769-770页

作者： Guang Dlan HAN Guo Feng HUANG(institute of Materia Medica, Peking Union Medical College, chinese {2. of Medical sciences, Beijing 100060) chinese Acad Med Sci Inst Mat Med Peking Union Med Coll Beijing 100050 Peoples R China

Abstract: The phenylseleno substituted aromatlc compounds were prepared via the Diels-Alder reaction of phenylseleno substituted dlenes with dimethyl acetylenedicarboxylate followed by DDQ dehydrogenation.

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Impaired long-term plasticity in the mice lacking xCT,a subunit of cystine/glutamate transporter

Impaired long-term plasticity in the mice lacking xCT,a subu...

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The 2.d International and 11th National Symposium on Membrane Biology

作者： Yan Li~(1,2.,Wei Li~1 1.Key Laboratory of Molecular and Developmental Biology,institute of Genetics and Developmental Biology,chinese academy of sciences,Beijing,{2. 2.Graduate University of chinese academy of sciences,Beijing,{2.

xCT is the functional subunit of amino acid transporting system X which exchanges extracellular cystine with intracellular *** has been demonstrated to play an important role in redox maintenance,mostly in vitro or under pathological *** we use sut mouse,an xCT null mutant,to explore the function of xCT under physiological

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Residues Met76 and Gln79 in HLA-G α1 domain involved in KIR2.L4 recognition

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Cell Research 2005年第3期15卷 176-182页

作者： Wei Hua YAN1,2.*,Li An FAN1,2.** 1Laboratory of Immunogenetics,Shanghai Second Medical University,2.0 South Chongqing Road,Shanghai 2.002.,china 2.aboratory of Immunogenetics,Shanghai institute of Immunology,2.0 South Chongqing Road,Shanghai 2.002.,china Laboratory of Immunogenetics Shanghai Second Medical University Shanghai China Laboratory of Immunogenetics Shanghai Institute of Immunology Shanghai China Laboratory Center Wenzhou Medical College Affiliated Taizhou Hospital LinHai China

Human leukocyte antigen-G (HLA-G) has long been speculated as a beneficial factor for a successful pregnancy for its restricted expression on fetal-maternal extravillous cytotrophoblasts and its capability of modulating uterine natural killer cell (uNK) function such as cytotoxicity and cytokine production through NK cell receptors. HLA class I α1 domain is an important killer cell Ig-like receptor (KIR) recognition site and the Met76 and Gln79 are unique to HLA-G in this region. NK cell receptor KIR2.L4 is a specific receptor for HLA-G, yet the recognition site on HLA-G remains unknown. In this study, retroviral transduction was applied to express the wild type HLA-G (HLA-wtG), mutant HLA-G (HLA-mG) on the chronic myelogenous leukemia cell line K562.cells and KIR2.L4 molecule on NK-92.cells, respectively. KIR2.L4-IgG Fc fusion protein was generated to determine the binding specificity between KIR2.L4 and HLA-G. Our results showed that residue Met76, Gln79 mutated to Ala76,79 in the α1 domain of HLA-G protein could affect the binding affinity between KIR2.L4 and HLA-G, meanwhile, the KIR2.L4 transfected NK-92.cells (NK-92. 2.L4) showed a considerably different cytolysis ability against the HLA-wtG and HLA-mG transfected K562.targets. Taken together, our data indicated that residue Met76 and Gln79 in HLA-G α1 domain plays a critical role in the recogni- tion of KIR2.L4, which could be an explanation for the isoforms of HLA-G, all containing the α1 domain, with the potential to regulate NK functions.

关键词： NK cell KIR2.L4 HLA-G receptor.

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Trophic importance of kelp-derived particulate materials to scallop Chlamys farreri in a polyculture farm in Sanggou Bay （Weihai,china）

Trophic importance of kelp-derived particulate materials to ...

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中国海洋湖沼学会第九次全国会员代表大会暨学术研讨会

作者： Qiang Xu Hongsheng Yang Hong Wang Fei Gao (1.institute of oceanology,{2.,No.7,Naihai road,Qingdao 2.6071,china 2.Graduate School,{2.,No.19,Yuquan Road,Beijing 100049,china)

＜正＞Trophic importance of kelp-derived particulate organic materials to co-cultured bivalve was investigated in a polyculture area of kelp Laminaria japonica and scallop Chlamys farreri,in Sanggou Bay（Weihai,china）.Dynamics of detritus carbon proportion in the water and the detrital diet of co-cultured scallop were monitored at four different periods in one cycle of kelp cultivation from February to August（2.06）.Results showed that,the detritus carbon in the water ranged from

关键词： polyculture kelp bivalve scallop carbon contribution

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Distribution of the Classification Traits in the F2.Progeny of Two Crosses of indica/japonica in Rice （Oryza sativa）

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Rice Science 2003年第Z1期 23-28页

作者： ZHANG Zai-jun~(1,2., LIANG Cheng-ye~2. ZHU Ying-guo~1 (~1 Key Laboratory of MOE for Plant Developmental Biology, Wuhan University, Wuhan 430072. china ~2.South china {2. of Botany, chinese academy of sciences, C, uangzhou 510650, china)

Comparison of seed setting rate, plant height and Cheng's morphological traits were made between the F2.rogeny of indica-japonica hybrids, 02.2./Pei'ai 64 and Taichung 65/Teqing. There existed resemblance normal distribution in plant height, and the distribution had no relationship with the seed setting rate and plant height in F1progeny, suggesting that there were no gametic selection for the plant height in the F2.rogeny of indica-japoniea hybrids. An average seed setting rate of the F2.as equal to the F1populations in the recombination of 02.2./Pei'ai 64 in which there was an excellent cross compatibility, but the remarkable increase in the seed setting rate from the F1to F2.n Taichung 65/Teqing, indicating that gametic selection only took place in the indica-japonica crosses with low cross compatibility while null or little in the hybrids with high compatibility. There were many intermediate types among the leaf pubescence, color of hull at heading, and length of the first and second panicle internode, and these Cheng's morphological traits was distributed normally; there were also a little intermediate types in hull hairness and phenol reaction with bi-peak distribution; while length to width ratio of grain was inclined to the japonica types obviously showing a skewed distribution in the F2.population. Although Cheng's morphological traits in F2.opulations had inconsistent distribution types, Cheng's morphological traits index showed normal distribution, which suggested that intermediate types, i.e. indicalinous or japonicalinous, were primary in F2.opulation.

关键词： rice indica-japonica crosses genetic effect generations distribution morphological traits seed setting rate plant height

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大鼠胚胎干细胞遗传操作技术的研究进展

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生物化学与生物物理进展 2011年第11期38卷 995-1000页

作者：孟姝中国科学院生物物理研究所蛋白质科学研究平台北京100101

大鼠胚胎干细胞(ES)的成功建立使大鼠的遗传学操作成为可能,运用同源重组原理改造ES细胞的基因,为建立时空特异性的基因敲除大鼠模型提供了基础.本文主要回顾了大鼠ES细胞的建立过程,总结了大鼠ES的培养、鉴定技术,分析了各种大鼠基因... 详细信息

大鼠胚胎干细胞(ES)的成功建立使大鼠的遗传学操作成为可能,运用同源重组原理改造ES细胞的基因,为建立时空特异性的基因敲除大鼠模型提供了基础.本文主要回顾了大鼠ES细胞的建立过程,总结了大鼠ES的培养、鉴定技术,分析了各种大鼠基因敲除技术的优劣势和未来前景.在干细胞研究蓬勃发展的背景下,作为最有效地定向修饰基因的技术手段,基于大鼠ES细胞的基因敲除技术将在揭示基因的生理功能、研究人类疾病的遗传机制以及寻找新药物靶标的过程中发挥更加重要的作用.

关键词： ES细胞遗传操作基因敲除干细胞

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Inhibitory effect of agmatine on proliferation of tumor cells by modulation of polyamine metabolism

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Acta Pharmacologica Sinica 2005年第5期26卷 616-622页

作者： Ji-fang WANG~2.Rui-bin SU~2.Ning WU,Bo XU,Xin-qiang LU,Yin LIU,Jin LI~3Beijing institute of Pharmacology and Toxicology,Beijing 100850,china Beijing institute of Pharmacology and Toxicology Beijing China

Aim:To assess the inhibitory effect of agmatine on tumor growth in vivo andtumor cell proliferation in ***:The transplanted animal model,[~3H]thymidine incorporation assay,3-[4,5-dimethythiazol-2.yl]-2.5-diphenyltetrazo-lium assay,and lactate dehydrogenase(LDH)release assay were ***:Agmatine,at doses of 5-40 mg/kg,suppressed the S180sarcoma tumorgrowth dose-dependently in mice in vivo and the highest inhibitory ratio reached31.3% in Kunming mice and 50.0% in Balb/c mice,*** resultswere obtained in the transplanted B16melanoma tumor ***(1-1000 μmol/L)was able to attenuate the proliferation of cultured MCF-7 humanbreast cancer cells in vitro in a concentration-dependent manner and the highestinhibitory ratio reached 50.3% in the[~3H]thymidine incorporation ***,in the LDH release assay,spermine(2.μmol/L)and spermidine(2.μmol/L)increased the LDH release significantly,but agmatine(1-1000μmol/L)did not,indicating that the inhibitory effect of agmatine on the proliferation ofMCF was not related to cellular *** the[~3H]thymidine incorporation assay,putrescine(12.5-100.0μmol/L)could reverse the inhibitory effect of agmatine onthe proliferation of MCF concentration-dependently,suggesting that the inhibi-tory effect of agmatine on the proliferation of MCF might be associated with adecreased level of the intracellular polyamines ***:Agmatine hadsignificant inhibitory effect on transplanted tumor growth in vivo and prolifera-tion of tumor cells in vitro,and the mechanism might be a result of inducingdecrease of intracellular polyamine contents.

关键词： agmatine polyamine tumor cell proliferation

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china's State Security in a Time of Peaceful Development: A New Issue on Research Agenda

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china & World Economy 2007年第1期15卷 77-86页

作者： Yizhou Wang Senior Research Fellow Institute of World Economics and Politics Chinese Academy of Social Sciences Beijing China

This paper holds that china＇s national security during its peaceful rise is a new issue on the research agenda, which requires new counter-measures and collective wisdom. The paper discusses five of china＇s objectives in addressing national security; namely, from highest to lowest priority, friction among big powers, the Taiwan Question, disputes over sovereignty, protection of interests overseas, and undertaking international responsibilities. Systematically achieving these objectives is of major importance for building up national defence and china＇s international image. china ＇s state security in the current period of peaceful development is a new issue on the research agendum, for politicians, the military, scholars and researchers alike. Extensive and in-depth discussion is needed. Global security commitments made by a big power might conflict with its own security interests and objectives. Judging by any standard, china＇s tasks are heavy and the road ahead is long.

关键词： big power frictions and mission global security national security Taiwan Question

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Light collection of the POLAR detector

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 43-46页

作者： DONG YongWei,LI YanGuo,WU BoBing,ZHANG YongJie & ZHANG ShuangNan Key Laboratory of Particle Astrophysics,institute of High Energy Physics,chinese academy of sciences,Beijing 100049,{2. Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China

POLAR is a compact polarimeter dedicated to measuring the polarization of GRBs between 50-350 *** light collection of 2.0 mm×6 mm×6 mm plastic bars has been simulated and optimized in order to get uniform response to X-rays at different points along one single *** to the Monte Carlo results,the amplitude uniformity strongly depends on the level of polishing of the scintillator surface and the covering.A uniformity of 89% is achieved with a prototype constructed by a non position-sensitive PMT and an array of 4×4 bars.

关键词： plastic scintillator light collection gamma-ray burst polarimeter

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