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Cosmogenic ^(21)Ne concentrations and exposure ages of summit bedrocks in the Grove Mountains,Antarctica

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Science china Earth Sciences 2010年第4期53卷 518-521页

作者： KONG Ping1,2,DING Lin2,LAI QingZhou2 & HUANG FeiXin3.1 Key Laboratory of the Earth’s Deep Interior,institute of geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,china 2 Key Laboratory of Continental Collision and Plateau Uplift,institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing 100085,china 3.institute of mineral resources Research,china Metallurgical geology Bureau,Beijing 100025,china Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China institute of mineral resources Research China Metallurgical Geology Bureau Beijing China

Various sources of 21Ne and 22Ne exist in surface rocks:cosmogenic,in situ nucleogenic from internal U and Th,trapped crustal nucleogenic and trapped *** paper reports the first measurement,in china,of cosmogenic 21Ne and 22Ne in surface *** developed a unique sample pre-treatment procedure that effectively removed inclusions inside quartz grains,and thus maximally reduced nucleogenic contributions of 21Ne and ***-heating experiments show that concen-trations of cosmogenic 21Ne and 22Ne in summit bedrock samples R9202 and R9203.from Grove Mountains,Antarctica,are(3.83.0.87)×108 and(5.22±0.51)×108 atoms/g,*** corresponding minimum exposure ages are 2.2±0.5 and 3.0±0.3.*** indicates that the ice sheet in East Antarctica was uncovered the crest of Mount Harding,a typical nunatak in Grove Mountains,since at least mid-Pliocene.

关键词： 21Ne cosmogenic nuclide exposure age Antarctica Grove Mountains

Converse Result on Szász-Type Operators

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Transactions of tianjin University 2010年第2期16卷 135-137页

作者：宋占杰 School of Sciences Tianjin University institute of TV and Image Information Tianjin University

Szasz-type operators can be constructed by a Poisson process. The purpose of this paper is to derive the converse result in connection with Szasz-type operators by Steckin-Marchaud-type inequalities and new Ditzian mo... 详细信息

关键词： Sz^isz-type operators Poisson process Steckin-Marchaud-type inequalities continuity approximation

Crossed Micro-bands in the Martensite Variant Pairs of a Thermomechanically Trained Cu-Zn-Al Alloy

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Journal of Materials Science & Technology 1995年第6期11卷 418-420页

作者： Qingan ZHANG and Nanju GU (Hebei institute of Technology tianjin, 3.013., china)(East china institute of Metallurgy,Ma’anshan, 243.02, china) Hebei Inst of Technology Tianjin China

The crossed micro-bands in the martensite variant pairs of a thermomechanically trained Cu25.66Zn-4.02Al (wt-%) alloy have been studied. It was found that the micro-bands pass through the interface from one martensite variant to another and their orientation inside different variants is distinct, which would remain in the parent phase after the reverse transformation and play an important role in the formation of preferential martensite. In fact, the crossed micro-bands are micro-twins for accommodating the stress fields generated during thermomechanically training

关键词： Zn Al Crossed Micro-bands in the Martensite Variant Pairs of a Thermomechanically Trained Cu-Zn-Al Alloy Cu

mineralization Ages of the Jiapigou Gold Deposits,Jilin

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Acta Geologica Sinica(English Edition) 1997年第2期71卷 180-188页

作者： Li Junjian Shen Baofeng Mao Debao Li Shuangbao Zhou Huifang and Cheng Yuming tianjin institute of geology and {3. resources,Chinese Academy of Geological Sciences, tianjin Nonferrous Metal Geological Exploration Bureau, Changchun, Jilin

The Jiapigou gold deposits are typical vein type deposits associated withArchaean greenstone belts in china. According to the crosscutting relationships between dykesand auriferous veins, single hydrothermal zircon U-Pb dating and quartz K-Ar,^(40)Ar-^(3.)Ar andRb-Sr datings, the main mineralization stage of the Jiapigou deposit has been determined to be2469-2475 Ma, while mineralization superimposition on the gold deposit occurred in1800-2000 Ma and 13.-272 Ma. They form a mineralization framework of one oldermetallogenic epoch (Late Archaean-Early Proterozoic) and one younger metallogenic epoch(Mesozoic) of gold deposits in Archaean greenstone belts in china.

关键词： mineralization age hydrothermal zircon gold deposit Jiapigou Jilin

Androgen and prostatic stroma

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Asian Journal of Andrology 2003年第1期5卷 19-26页

作者： Yuan-Jie NIU, Teng-Xiang MA, Ju ZHANG, Yong XU, Rui-Fa HAN, Guang SUNDepartment of Prostatic Disease, tianjin institute of Urologial Surgery, tianjin Medical University,tianjin 3.0211, china Department of Prostatic Disease Tianjin Institute of Urologial Surgery 23 Pingjiang Road Hexi District Tianjin 300211 Chin

Aim: To investigate the effect of androgen on the proliferation, differentiation and regression of canine prostatic stromal cells in vivo and human stromal cells in vitro. Methods: Twenty-two dogs, including 15 normal prostate dogs and 7 prostatic hyperplasia dogs, had their serum concentration of testosterone and estrodiol determined by radioimmunoassay before and after castration. The expression of androgen receptor (AR) and estrogen receptor (ER) in the prostate were analysed by immunohistochemistry and semi-quantitative RT-PCR before and after castration. Light microscopy, transmission electron microscopy and TUNEL assay were carried out successively before and after castration to evaluate the prostatic histomorphology. In vitro serum-free cell cultures from human prostatic stroma were established and exposed to dihydrotestosterone (DHT). The proliferation of the cell culture was detected by MTT assay. The expression of TGFβ, bFGF, AR, and smooth muscle cell (SMC) specific proteins (myosin and/or smoothelin) were detected using immunohistochemistry and RT-PCR. The differentiation from fibroblasts to smooth muscle cells was deduced by measuring the expression of SMC specific proteins. Results: Before castration, the serum concentrations of testosterone and estrodiol were not statistically different between normal and hyperplasia groups. Following castration, the serum concentration of testosterone decreased rapidly in 2 days, and the concentration of estrodiol had no significant change compared with the pre-castration data. In the prostate, AR was presented in both the epithelial and stromal cells and the AR mRNA level was higher in hyperplasia than in normal prostate tissues (P<0.05). While ER predominantly existed in the prostate stromal cells and the ER mRNA had no difference between the hyperplasia and the normal group. Within the early phase of castration (

关键词： androgen castration androgen receptor prostatic stroma smooth muscle cells

Changes of infrared absorption wave number of aromatic-ring C=C bond of vitrinite and their significance

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Chinese Science Bulletin 1998年第12期43卷 1048-1050页

作者： XIAO Jianxin 1 and CHEN Shanqing 2 1. china University of Geosciences, Beijing 100083. china 2. Yichang institute of {3. and mineral resources, Yichang 443.03. china china University of Geosciences Beijing China Yichang institute of geology and mineral {3. Yichang China

The humilith series of lignite, longflame coal, gas coal, fat coal, coking coal, lean coal, meagre coal and anthracite are measured by FIR1600 infrared spectrophotometer. The variation curve between the infrared absorption wave number of aromaticring C--C bond of vitrinite and its reflectance values are gained, which shows the shift of infrared absorption wave number of aromaticring C--C bond of humic coals towards lower wave number with the increase of coalification. It is believed that the coal rank of humilith series can be determined and more evolutional information about coal composition and structure can be obtained by the infrared spectroscopic method.

关键词： aromatic_nucleus C--C bond infrared absorption wave number vitrinite humic coal.

Characterization of plastic flow in two Zr-based bulk metallic glasses

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Science china(Technological Sciences) 2006年第4期49卷 414-424页

作者： XING Dongmei1,2, ZHANG Taihua1, LI Weihuo3.& WEI Bingchen3.1. State Key Laboratory of Nonlinear Mechanics (LNM), institute of Mechanics, Chinese Academy of Sci- ences, Beijing 100080, china 2. College of Physics and Electronic Information Science, tianjin Normal University, tianjin 3.0074, china 3. National Microgravity Laboratory, institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, china State Key Laboratory of Nonlinear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China sychology.lu.se

Plastic deformation behaviors of Zr65Al10Ni10Cu15 and Zr52.5Al10Ni10Cu15Be12.5 bulk metallic glasses (BMGs) are studied by using the depth-sensing nanoindentation, microindentation and uniaxial compression. The Be-containing BMG exhibits a signifi- cantly improved overall plastic strain compared with the Be-free alloy during compressive tests. Both BMGs show a loading-rate-dependent serrated flow during nanoindentation measurements, but the Be-containing alloy exhibits a much lower critical loading rate for the disappearance of the serration than the Be-free BMG. The shear band patterns de- veloped during plastic deformation are investigated by microindentation technique, wherein much higher shear band density is found in the Be-containing alloy than in the Be-free alloy, indicating an easier nucleation of shear bands in the former BMG. The dif- ference in the plastic deformation behavior of the two BMGs can be explained by a free volume model.

关键词： Bulk metallic glass, plastic deformation, shear band, nanoindentation.

NEW MIDDLE TRIASSIC NOTOSTRACA (CRUSTACEA) FROM TOKSUN COUNTY, NORTH XINJIANG

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Chinese Science Bulletin 1980年第9期25卷 763-766页

作者：洪友崇 tianjin institute of geology and {3. resources Ministry of Geology

The fossils of one new genus and three new species described in this paper were collected from the grey-brownish sandstone of the Kelamayi Formation （克拉玛依组）（Xiaoquangou Group） in Toksun County （托克逊）, North Xinjiang. In age the formation may be referred to as the Middle Triassic （T2K）; and the fossils, a new Middle Triassic Notostraca （Crustacea）. They are Xinjiangiops suni g.s.n., Xin. Keerjianensis and Xin. tuokexunensis g.s.n.

关键词： Triassic Crustacea Middle sandstone 托克逊克拉玛依组 referred groove holotype preserved

Microfossils from the Wumishan Formation of the Jixian System in the Ming Tombs,Beijing,china

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Acta Geologica Sinica(English Edition) 1986年第4期 13-22+97-98页

作者： Zhang Pengyuan tianjin institute of geology and {3. resources, Chinese Academy of Geological Sciences, tianjin Gu Shuqin Beoing Geological Survey, Beijing Bureau of geology and {3. resources, Beijing

Members Ⅰ-Ⅳ of the Wumishan Formation of the Jixian System are exposed respectively in Mt. Cuihua and Mt. Hushan in the Ming Tombs, Beijing. Black banded cherts which are extensively developed in this formation contain an abundance ofmicrofossils that are well preserved and variable in form. A study of thin sections shows that the microfossils include 10 genera, 12 species, 3.of. species, 2 indeterminate species and 1 unnamed form, of which 1 genus and 7 species are newly erected. The present assemblage is morphologically comparable to those from the Wumishan Formation in the Western Hills of Beijing, Jixian County of tianjin and Kuancheng of Hebei Province.

关键词： BW Microfossils from the Wumishan Formation of the Jixian System in the Ming Tombs,Beijing,china