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外国教育研究 2005年第10期32卷 48-52页

作者：史朝国家教育行政学院国际教育部北京102617

研究型大学的本科课程改革是一个世界性的课题。文章通过对中国和日本几所研究型大学本科课程改革进行比较研究,提出了一系列值得重视的观点。这对于当前我国大学的本科课程建设具有重要意义。

关键词：中国日本研究型大学本科课程比较研究

New exact solutions for free vibrations of rectangular thin plates by symplectic dual method

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Acta Mechanica Sinica 2009年第2期25卷 265-270页

作者： Y. Xing B. Liu The Solid Mechanics Research Center, Beihang University, 100083 beijing, china The Solid Mechanics Research Center Beihang University Beijing China

The separation of variables is employed to solve Hamiltonian dual form of eigenvalue problem for transverse free vibrations of thin plates, and formulation of the natural mode in closed form is performed. The closed-form natural mode satisfies the governing equation of the eigenvalue problem of thin plate exactly and is applicable for any types of boundary conditions. With all combinations of simplysupported （S） and clamped （C） boundary conditions applied to the natural mode, the mode shapes are obtained uniquely and two eigenvalue equations are derived with respect to two spatial coordinates, with the aid of which the normal modes and frequencies are solved exactly. It was believed that the exact eigensolutions for cases SSCC, SCCC and CCCC were unable to be obtained, however, they are successfully found in this paper. Comparisons between the present results and the FEM results validate the present exact solutions, which can thus be taken as the benchmark for verifying different approximate approaches.

关键词： Classical theory of thin plate Frequency Free vibrations Symplectic dual method Exact solution

Influence of Hydrogen on the Microstructures and Superplasticity of a Ti_3Al-Nb Alloy

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Rare Metals 2001年第2期20卷 87-90页

作者： Hua Ding, Bingzhe Bai, Dingliang Wang, Dan Song, Caipei Zhang, Jianzhong Cui,Luyi Yang (Northeastern University, Shellyang 110006, china Tsinghua University, beijing 100084, china beijing Research Institute of Mechanical and Electrical Technology, Be 东北大学辽宁沈阳 110006 清华大学北京 110006 机械部北京机电所北京 110006

The effect of hydrogen on the microstructures and superplasticity of a Ti3Al-Nb alloy was studied. The results showed that hydrogenation made the volume fraction of B2 phase increase and facilitated the dynamic recrystallization of the lath-like phase. The addition of hydrogen. reduced the flow stresses and made the maximum m value move to a lower temperature during the superplastic deformation. The superplastic deformation temperature of the alloy can be lowered by about 60 degreesC.

关键词： Ti,Al-Nb alloy thermohydrogen processing (THP) microstructure superplasiticity

Development of chinese characterization factors for land use in life cycle impact assessment

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Science china(Technological sciences) 2010年第6期53卷 1483-1488页

作者： LIU Yu,NIE ZuoRen,SUN BoXue,WANG ZhiHong & GONG XianZheng School of Materials Science and Engineering,beijing University of Technology,beijing 100124,china School of Materials Science and Engineering Beijing University of Technology

A model with chinese characterization factors for quantifying the damages to environment by land use in terms of the change in net primary productivity (NPP) of ecosystem was developed in the framework of life cycle assessment (LCA).In this method,the forms of land utilization were divided into two aspects involving long-term use of land (e.g.,for arable farming),namely "land occupation",and the change of land properties (e.g.,from agricultural area to urban area),namely "land transformation".Furthermore,the land use elementary flows (occupation and transformation) and parameters were linked to the impact indicators,and the characterization formulas of the two forms of land utilization were derived respectively according to the ecological ***,based on this method,the characterization factors of both land occupation and land transformation were calculated using chinese empirical information on NPP,which can be incorporated into LCA framework and applied to chinese LCA case study to fill up the important gap in life cycle impact assessment (LCIA) of land use.

关键词： life cycle assessment land use net primary productivity

Cisplatin-induced premature senescence with concomitant reduction of gap junctions in human fibroblasts

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Cell Research 2004年第1期14卷 60-66页

作者： Wei ZHAO, Zhong Xiang LIN, Zhi Qian ZHANG Peking University School of Oncology, and beijing Institute for Cancer Research, beijing 100034, china. Lin ZX Peking Univ Sch Oncol Beijing 100034 Peoples R China

To examine the role of gap junctions in cell senescence, the changes of gap junctions in cisplatin-induced premature senescence of primary cultured fibroblasts were studied and compared with the replicative senescent human fibroblasts. Dye transfer assay for gap junction function and immunofluorescent staining for connexin 43 protein distribution were done respectively. Furthermore, cytofluorimetry and DAPI fluorescence staining were performed for cell cycle and apoptosis analysis, p53 gene expression level was detected with indirect immunofluorescence. We found that cisplatin (10 mM) treatment could block cell growth cycle at G1 and induced premature senescence. The premature senescence changes included high frequency of apoptosis, elevation of p53 expression, loss of membranous gap junctions and reduction of dye-transfer capacity. These changes were comparable to the changes of replicative senescence of human fibroblasts. It was also concluded that cisplatin could induce premature senescence concomita

关键词： cisplatin premature senescence gap junction intercellular communication connexin 43 fibroblasts.

AN AREA OF ENDEMISM OF CERCOPOID SPITTLEBUGS （HEMIPTERA: CERCOPOIDEA） IN THE SOUTHERN TIBET AND ADJACENT AREAS

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AN AREA OF ENDEMISM OF CERCOPOID SPITTLEBUGS （HEMIPTERA: CE...

The Fourth International Conference on Electronic Business (ICEB2004)

第十九届国际动物学大会

作者： Ai-Ping LiangDepartment of Entomology Institute of Zoology chinese academy of sciences 19 Zhongguancun Road Haidian District beijing100080 P. R. china

＜正＞The cercopoid fauna （Hemiptera: Auchenorrhyncha: Cercopoidea） of the southern Tibet and the adjacent areas are summarized and the principle zoogeograph-ical features are analyzed. Both Oriental and Palaearc-tic elements of Cercopoidea are present in the southern Tibet and the adjacent areas but the Oriental element is predominant （93% of the fauna）. Endemism

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Systems Science and Systems Engineering 2004年第2期13卷 253-256页

作者： Tsinghua University, beijing, china

Co-organizersTsinghua University, beijing, chinaThe national University of Singapore, Singaporenational Chiao Tung University, Taiwan, chinaThe chinese University of Hong Kong, Hong Kong, china

关键词： Co ICEB2004 The Fourth International Conference on Electronic Business

Hearing and Cochlear structures in a Swine Model

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Journal of Otology 2010年第2期5卷 97-100页

作者： GUO Wei-wei1,Cheng Lei2,Liu Hui-zhan1,Sun Jian-he1,YANG Shi-ming1,1 Department of Otolaryngology,Head & Neck Surgery,Institute of Otolaryngology,chinese PLA General Hospital,beijing 100853,china 2 State Rey laboratory for Agrobio technology china Agrical universiy beijing 100193,PR,china Department of Otolaryngology Head & Neck Surgery Institute of OtolaryngologyChinese PLA General Hospital Beijing 100853 China State Rey laboratory for Agrobio technology china Agrical university beijing 100193 PR China

Objective To study the audition and inner ear structure in a normal swine *** Auditory brainstem responses(ABRs) were determined in swine at 1 day and 1 month after *** form of the cochlea and hair cells were examined under a scanning electron microscope and on cochlear *** ABR thresholds at 1 day and 1 month post-birth were between 40 and 50 dB *** latencies of waves I,III and V in 1 day old swine were 1.97 ± 0.13,3.01± 0.16 and 4.26±0.20 ms,*** 1 month,the lantancies of waves I,III and V were 2.01 ± 0.05,3.11±0.08 and 4.65 ± 0.14 ms,respectively,slightly longer than those at 1 day,although not statistically significant(p>0.05).The swine cochlea was constituted of 3 and a half turns and the cochlear hair cells lined up in four *** cell cilia in the apical turn were longer than those in other *** The swine cochlea is mature at the time of *** ABR thresholds are slightly higher than humans and *** appears to be a precocial animal species.

关键词： Swine ABR morphology

Virus proteins regulate host activity by ubiquitination pathway

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Virus proteins regulate host activity by ubiquitination path...

A Modified Integrated Model of the Internal Structure of chinese Cultured Pearls

2011全国植物生物学研讨会

作者： Zhonghui Zhang,Jianbin Lai and Qi Xie~* State Key Laboratory of Plant Genomics,national Center for Plant Gene Research,Institute of Genetics and Developmental Biology,chinese academy of sciences,Datun Road,beijing 100101, china

Plant viruses are excellent tools for studying microbial-plant interactions,as well as the complexities of host *** present study focuses on the role of C2 and C4 encoded by Beet severe curly top virus(BSCTV) in the virus-plant interaction.C4 protein from Curtovirus was known as a major symptom *** understand the mechanism of C4 protein in virus-plant interaction,we introduced the C4 gene from Beet severe curly top virus(BSCTV) into Arabidopsis under a conditional expression ***1/RKP,a RING finger protein,which is a homologue of a human cell cycle regulator KPC1,was discovered to be induced by BSCTV C4

关键词： ubiquitination geminivirus plant host interaction de novo methylation

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Journal of Wuhan University of Technology(Materials Science) 2011年第3期26卷 510-513页

作者：马红艳 Key Laboratory of Nonferrous Metals and New Material Processing Technology Ministry of EducationCollege of Materials Science and EngineeringGuangxi University

Optical and micro-infrared microscope were used to observe the internal structure and mineral composition of high and low quality chinese seawater and freshwater cultured *** clearly reveal that aragonite and calcite are found in seawater cultured pearls,but vaterite is not *** contrast,vaterite and aragonite are found in freshwater cultured pearls,but calcite is not *** on our analysis and observations of the internal structure of high and low quality cultured pearls,a modified integrated model of the internal structure of chinese cultured pearls was *** revisions to the previous model focus on significant differences within the prismatic layer of chinese cultured pearls.

关键词： cultured pearls aragonite vaterite calcite integrated model