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38CrSi钢表面纳米结构层力学性能的研究

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材料热处理学报 2007年第5期28卷 115-119页

作者：巴德玛马世宁孟凡军装甲兵工程学院装备再制造技术国防科技重点实验室北京100072

采用超音速微粒轰击技术在38CrSi合金钢表面制备了厚度约为25μm纳米晶层。利用X射线衍射、扫描电镜和透射电镜对表面结构进行分析。纳米结构层的最表面层的晶粒尺寸约为16nm,晶粒尺寸随着距表面距离的增加而增大。利用纳米压痕仪对表... 详细信息

采用超音速微粒轰击技术在38CrSi合金钢表面制备了厚度约为25μm纳米晶层。利用X射线衍射、扫描电镜和透射电镜对表面结构进行分析。纳米结构层的最表面层的晶粒尺寸约为16nm,晶粒尺寸随着距表面距离的增加而增大。利用纳米压痕仪对表面纳米结构层的力学性能进行研究,结果表明,当表面晶粒尺寸降低到纳米量级时力学性能明显改善,最表面纳米结构层的硬度是基体的2倍左右,并服从Hall-Petch关系;表面纳米结构层的弹性恢复系数明显提高;利用该方法制备的纳米晶对弹性模量的影响较小;对表面纳米化样品进行低温退火处理可使纳米结构层的性能更加稳定。分析表明表面纳米结构层力学性能的改善主要是表面晶粒细化的结果。

关键词：表面纳米化纳米结构层 38CrSi钢力学性能

用PEM监控制备TiO2薄膜及其光学性能的研究

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东北大学学报（自然科学版） 2008年第6期29卷 885-888页

作者：段永利巴德纯许生范垂祯东北大学机械工程与自动化学院辽宁沈阳110004 深圳豪威真空光电子股份有限公司广东深圳518057

使用金属钛作靶材,利用中频反应磁控溅射方法在玻璃基底上制备了TiO2薄膜.为使反应溅射的工作点能够稳定在"过渡区",使薄膜获得理想的化学配比和较高的沉积速率,使用了等离子体发射光谱监控法(PEM)对溅射过程进行控制.利用台阶仪测膜厚,... 详细信息

使用金属钛作靶材,利用中频反应磁控溅射方法在玻璃基底上制备了TiO2薄膜.为使反应溅射的工作点能够稳定在"过渡区",使薄膜获得理想的化学配比和较高的沉积速率,使用了等离子体发射光谱监控法(PEM)对溅射过程进行控制.利用台阶仪测膜厚,用X射线衍射仪、原子力显微镜、分光光度计以及光学薄膜测试分析仪等手段对TiO2薄膜的结构以及光学性能进行表征,研究了不同工艺条件对薄膜结构和光学性能的影响.结果表明,较高的PEM工作点下制备的TiO2薄膜具有较高的折射率,使用PEM控制的中频反应磁控溅射方法可以制备出性能良好的TiO2光学薄膜.

关键词： TiO2薄膜反应溅射 PEM控制光学性能薄膜结构

Investigation of Genetic Variation of B-G Gene with PCR-SSCP and RFLP in Chinese Indigenous Chickens

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Agricultural Sciences in China 2005年第8期4卷 621-628页

作者： XU Ri-fu LI Kui CHEN Guo-hong QIANG-ba Yang-zong XU Hai MO de-lin LI Chang-chun FAN Bin LIU bang Laboratory of Molecular Biology and Animal Breeding College of Animal Science and Technology Huazhong Agricultural University Wuhan 430070 P.R.China Institute of Animal Science Chinese Academy of Agricultural Sciences Beijing 100094 P.R. China department of Animal Science and Technology Yangzhou University Yangzhou 225009 P.R.China department of Animal Husbandry and Veterinary College of Agriculture and Animal Husbandry Tibetan University Linzhi 860000 P. R. China

To reveal genetic variation of MHC B-G gene at Chinese native chickens, two PCR primer pairs were designed to hybridize specifically with conserved sequences surrounding hypervariable regions within the B-G gene and used to amplify two DNA fragments in ten Chinese indigenous chicken breeds and one introduced breed. The fragments were cloned and sequenced to assure that the expected sequences of chicken B-G gene were isolated. Of which the 189 bp fragment encompassing the most variable region within exon 2 of B-G gene was employed for PCR-SSCP assay, this method provided evidence for the presence of at least 56 B-G genotypes in the Chinese chickens sampled. It revealed a high degree of diversity in B-G genes of Chinese local breeds; particularly, high variation of B-G gene was confirmed with the presence of 48 B-G genotypes within Tibetan chicken population. Not only can the B-G genotypes be used to preliminarily screen new B-G alleles, but also they would be utilized to investigate MHC haplotypes and matched unrelated donors for bone marrow transplantation in immune researches. Another fragment of 401 bp size spanning over partial intron 1 and exon 2 of B-G gene was employed for PCR-RFLP analysis with two restriction enzymes of Msp Ⅰ and Tas Ⅰ in the breeds sampled. In this part of the gene, three novel SNPs were detected at the two restriction sites. It was more generally found the transition of two nucleotides of A294G and T295C occurred at Tas Ⅰ restriction site, and consequently led to a non-synonymous substitution of asparagine into serine at position 54 within the deduced amino acid sequence of immunoglobulin variable-region-like domain encoded by the exon 2 of B-G gene. It was observed at rare frequency that an alone mutation of A294G occurring at the site, which also caused the substitution of amino acid, asparagine 54-to-serine; and we haven＇t found only single mutation occurred at position 295 of the restriction site. At the Msp Ⅰ site, the transversion o

关键词： B-G genes PCR-SSCP assay Genetic variation Chinese indigenous chicken Genotype Allele

Abnormal expression of CD43 in patients with systemic lupus erythematosus and its clinical significance

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Chinese Medical Journal 2012年第7期125卷 1266-1271页

作者： XIA Li-xia DING Xin LI Xin ZHANG Feng-chun TANG Fu-lin ZHANG Xuan ba de-nian HE Wei department of Rheumatology Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China department of Immunology School of Basic MedicinePeking Union Medical College and Institute of Basic Medical SciencesChinese Academy of Medical SciencesBeijing 100005

background Previous studies indicate that CD43 plays a role in regulating the adhesion of lymphocytes, cell mutation and activation, however, little is known about its effect on systemic lupus erythematousus （SLE）. This study was designed to explore the clinical significance of CD43 in SLE patients. Methods We used microarray and real-time PCR to detect the mRNA and protein expression of magnetic bead sorted T cells and B cells from peripheral blood mononuclear cells （PBMCs） of SLE patients, and analyzed the relationship between CD43 and the clinical indexes. Results Both microarray and real-time PCR results showed that CD43 mRNA was significantly decreased in PBMCs of SLE patients compared with healthy controls （P 〈0.001）. There were no significant differences between lupus nephritis and non-lupus nephritis patients, and neuropsychiatric and non-neuropsychiatric patients. CD43 mRNA expression was significantly reduced in T cells but not in B-cells in SLE patients compared to healthy controls （P 〈0.01）. Compared with healthy controls, the percentage of CD43~ cells in the PBMCs of SLE was significantly decreased （P----0.004）, and the CD43 fluorescence intensity in CD3~/CD43~ cells and CD19＋/CD43~ cells was also significantly weaker than in healthy controls （P=0.039 and 0.003）. There was no significant difference in the percentage of CD3~/CD43＋ cells, CD19~/CD43~ cells between the two groups. The CD43 fluorescence intensity in CD3＋/CD43~ cells was inversely correlated with the levels of IgG and IgM （r=-0.8 and -0.6）. Conclusions Compared to healthy controls, both CD43 mRNA and protein expressions were reduced in T cells from patients with SLE, and were inversely correlated with IgG.

关键词： systemic lupus erythematosus peripheral blood mononuclear cell CD43

Synthesis, Characterization and Antitumor Activities of Co, Ni, Cu, Zn Complexes with 1,4,7,10-tetrakis(4-nitrobenzyl)-1,4,7,10 tetraazacyclododecane Macrocyclic Ligand

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Chinese Journal of Structural Chemistry 2000年第1期19卷 39-47页

作者： KONG de\|Yuan a* \ XIE Yu\|Li a\ XIE Yu\|Yuan a\ HUANG Xiao\|Ying ba (Shanghai Institute of Materia Medica, the Chinese Academy of Sciences, Taiyuan Road 294, Shanghai, 200031, P. R. China) b (department of Chemistry, Rugters University, New Jer 中科院上海药物所上海 2 0 0 0 31 Rugters University 美国 New Jersey 08102

New tetraazamacrocyclic ligand with 1,4,7,10 tetrakis(4 nitrobenzyl) pendent groups (C 36 H 40 N 8O 8, M r =712.76) crystallized in the monoclinic system, P2 1/n space group with unit cell parameters: a=7.834(2), b=22.902(6), c=10\^147(3), β=106.53(2)°, V=1745(1) 3, Z=2, D c =1.356 g/cm 3, λ (Mo Kα )=0.71069; μ =0.92cm -1 , F(000)=752, T =296K. The final R and R w values are 0\^065 and 0.066, respectively. The Cu(Ⅱ), Ni(Ⅱ), Co(Ⅱ), Zn(Ⅱ) complexes with this new ligand have been synthesized and characterized by elemental analyses, IR, UV, ESI MS and molar conductance. The macrocyclic ligand molecular structure is centrosymmetrical. All complexes are in accordance with the general formula: M(L)(NO 3) 2·nH 2O (M=Co, Ni, Cu, n=2; M=Zn, n=4; L=C 36 H 40 \|N 8O 8). The central metal ions coordinate to four nitrogen atoms of azamacrocycle and two oxygen atoms of one nitrate ion. Preliminary pharmacological tests against P 388 and A 549 tumor cell lines showed that all these complexes had considerable activities in vitro.

关键词： synthesis macrocyclic ligand antitumor activity crystal structure

p53 in fibroblast-like synoviocytes can regulate T helper cell functions in patients with active rheumatoid arthritis

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Chinese Medical Journal 2011年第3期124卷 364-368页

作者： TANG Bi-xia YOU Xin ZHAO Li-dan LI Yang ZHANG Xuan TANG Fu-lin ba de-nian HE Wei department of Rheumatology Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100032 China department of Immunology School of Basic Medicine Peking Union Medical College and Institute of Basic Medical SciencesChinese Academy of Medical Sciences Beijing 100005 China

background p53 is a tumor suppressor and plays a key role in regulating cell hyperplasia, repairing DNA and inducing apoptosis. This study was to investigate p53 expression in fibroblast-like synoviocytes （FLS） and its effect on CD4＋ T lymphocytes from patients with active rheumatoid arthritis （RA）.Methods Human FLS were transfected with p53 siRNA and cocultured with CD4＋ T lymphocytes from patients with active RA. The expressions of osteoprotegerin and interleukin （IL）-6 were detected in p53 siRNA and scramble siRNA-transfected FLS. In addition, protein levels of interferon （IFN）-γ, IL-17, IL-4 and CD25 as well as mRNAs of IFN-γ,retinoic acid-related orphan receptor （ROR）-γt, IL-17 and Foxp3 in cocultured CD4＋ T lyrmphocytes were also *** IL-6 decreased in p53-knockdown FLS while osteoprotegerin expression was not altered. FLS with p53 deletion significantly increased the production of IL-17 and IFN-γ by CD4＋ T cells and upregulated Foxp3 mRNA expression without effects on the proportion of CD4＋CD25high T *** p53 in FLS might regulate Th1 and Th17 functions in patients with RA and participate in the pathogenesis of RA.

关键词： rheumatoid arthritis p53 helper T-cells

基于动网格的滚动活塞压缩机泵腔流动瞬态模拟

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东北大学学报（自然科学版） 2011年第4期32卷 563-566页

作者：岳向吉巴德纯苏征宇张宇东北大学机械工程与自动化学院辽宁沈阳110819 沈阳华润三洋压缩机有限公司辽宁沈阳110044

基于动网格方法建立了滚动活塞压缩机泵腔流动的三维瞬态数值模拟模型,模拟结果与理论工作循环对比表明该模型反映了滚动活塞压缩机工作的基本过程,可以用于泵腔流场的研究.模拟了气体在泵腔内的流动过程,给出了直观丰富的泵腔流动信息... 详细信息

基于动网格方法建立了滚动活塞压缩机泵腔流动的三维瞬态数值模拟模型,模拟结果与理论工作循环对比表明该模型反映了滚动活塞压缩机工作的基本过程,可以用于泵腔流场的研究.模拟了气体在泵腔内的流动过程,给出了直观丰富的泵腔流动信息,对泵腔内的流动现象和流场分布进行了分析,指出了压缩机吸气、压缩和排气时流场的主要特征.研究结果为滚动活塞压缩机泵体结构的优化提供了理论依据,并为整机流场的进一步研究提供了重要参考.

关键词：滚动活塞压缩机计算流体力学(CFD) 动网格流场数值模拟

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某型航空发动机空中起动供油规律的研究

航空动力学报 2010年第5期25卷 1163-1168页

作者：王兆铭王福德左伟王晨巴德纯东北大学机械工程与自动化学院沈阳110004 中国航空工业集团公司沈阳发动机设计研究所沈阳110015 中国人民解放军驻沈阳黎明发动机制造公司军事代表室沈阳110043 大连理工大学能源与动力学院大连116023

研究某型航空发动机空中起动困难问题,现有自动起动器没有考虑飞行高度对供油规律的影响,发动机在空中起动时存在富油状态.分析了影响起动供油规律的因素,在现有自动起动器结构基础上,设计了高空修正模块来补偿飞行高度对供油规律的影响... 详细信息

研究某型航空发动机空中起动困难问题,现有自动起动器没有考虑飞行高度对供油规律的影响,发动机在空中起动时存在富油状态.分析了影响起动供油规律的因素,在现有自动起动器结构基础上,设计了高空修正模块来补偿飞行高度对供油规律的影响.建立了自动起动器的数学模型,对改进的自动起动器进行了仿真分析和试验.仿真结果和试验验证了改进方案的可行性,与地面起动相比,空中起动的供油量随着飞行高度的增加而降低.采用改进的空中起动供油规律可补偿飞行高度对供油特性的影响,解决发动机空中起动时的富油状态问题.

关键词：航空发动机燃油调节器自动起动器空中起动供油规律

Inventory and Geometrical Changes in Small Glaciers Covering Three Northern Patagonian Summits Using Remote Sensing and GIS Techniques

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Journal of Mountain Science 2010年第1期7卷 26-35页

作者： Alfonso Fernández José Araos Jorge Marín department of Geography Faculty of Architecture Urbanism and Geography Universidad de Concepción Centro de Estudios Avanzados en Zonas áridas (Ceaza)

In the last few decades, a large quantity of research has been performed to elucidate the current behavior of glaciers in southern Chile, especially with respect to the volumetric changes in the outlets of the Northern and Southern Patagonian Icefields （NPI and SPI, respectively）. Calculations have shown a generalized thinning and withdrawal, which greatly contributes to the increase in sea level attributed to the ice melt from non-polar glaciers. However, these icefields are surrounded by many small icecaps, which have＇yet to be studied in detail. A precise estimation of the volume of ice located in these mountain chains could provide new information with respect to this area＇s exact contribution to the increase in sea level. Thus, this study presents an inventory of relatively small Northern Patagonian glaciers in the surrounding of the three summits： Mount Queulat, and the Maca and Hudson volcanoes. The study used remote sensing techniques in a GIS environment to determine the margins, surface areas, thickness changes and hypsometry for the glaciated zones. Landsat images from different dates were analyzed using standard band ratio and screen delineation techniques. Additionally, digital elevation models from different dates were compared using map algebra, calculating thickness changes. based on the results, we propose that there are important volumetric changes in the glaciers studied, whichcould be explained by precipitation trends in a general context, and an influence of the glaciers＇ sizes in some local response. Therefore, we suggest the exact contribution of the Patagonia to the increase in sea level corresponds to a regional pattern rather than just the behavior of a single ice field.

关键词： Glacier inventory thickness change digital elevation model morphometric measurement