检索结果-南通市图书馆

Effects of Ta Addition on Microstructure and Transformation Behavior of Ni-Ti Alloys

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2001年第1期17卷 5-6页

作者： K.H.Wu and JL.Ma Department of Mechanical Engineering, Florida International university, miami, FL 33174, U.S.A. Florida Int Univ Dept Mech Engn Miami FL 33174 USA

The effect of adding Ta on the changes of microstructure and Ms temperature of a dualphase shape memory alloy with compositions of (Ni51 Ti49)1 -***. and Ni50-Ti50 -***.g were systematically studied. An optical microscope, SEM, X-ray diffraction and DSC were utilized in this work. The evolution of the microstructure as a function of Ta content was characterized. The variation of the Ni/Ti ratio in the NiTi phase plays an important role in the change of the Ms temperatures due to the addition of Ta. A pseudobinary NiTi-Ta phase diagram was proposed based on these results.

关键词： Ti Ta Effects of Ta Addition on Microstructure and Transformation Behavior of Ni-Ti Alloys

Mechanism for calcite dissolution and its contribution to development of reservoir porosity and permeability in the Kela 2 gas field,Tarim Basin,China

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2008年第4期51卷 567-578页

作者： YU BingSong1,3, DONG HailLiang2,3 & RUAN Zhuang1,3 1 State Key Laboratory of Geological Processes and Mineral Resources, China university of Geosciences, Beijing 100083, China 2 Department of Geology, miami university,Oxford, OH 45056, USA 3 Geomicrobiology Laboratory, China university of Geosciences, Beijing, 100083, China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Department of Geology Miami University Oxford OH 45056 USA Geomicrobiology Laboratory China University of Geoscien

This study is undertaken to understand how calcite precipitation and dissolution contributes to depth-related changes in porosity and permeability of gas-bearing sandstone reservoirs in the Kela 2 gas field of the Tarim Basin, Northwestern China. Sandstone samples and pore water samples are col-lected from well KL201 in the Tarim Basin. Vertical profiles of porosity, permeability, pore water chem-istry, and the relative volume abundance of calcite/dolomite are constructed from 3600 to 4000 m below the ground surface within major oil and gas reservoir rocks. Porosity and permeability values are in-versely correlated with the calcite abundance, indicating that calcite dissolution and precipitation may be controlling porosity and permeability of the reservoir rocks. Pore water chemistry exhibits a sys-tematic variation from the Na2SO4 type at the shallow depth (3600-3630 m), to the NaHCO3 type at the intermediate depth (3630―3695 m),and to the CaCl2 type at the greater depth (3728―3938 m). The geochemical factors that control the calcite solubility include pH, temperature, pressure, Ca2+ concen-tration, the total inorganic carbon concentration (ΣCO2), and the type of pore water. Thermodynamic phase equilibrium and mass conservation laws are applied to calculate the calcite saturation state as a function of a few key parameters. The model calculation illustrates that the calcite solubility is strongly dependent on the chemical composition of pore water, mainly the concentration difference between the total dissolved inorganic carbon and dissolved calcium concentration (i.e., [ΣCO2] -[Ca2+]). In the Na2SO4 water at the shallow depth, this index is close to 0, pore water is near the calcite solubility. Calcite does not dissolve or precipitate in significant quantities. In the NaHCO3 water at the intermedi-ate depth, this index is greater than 0, and pore water is supersaturated with respect to calcite. Massive calcite precipitation was observed at this depth interval and

关键词： calcite dissolution porosity thermodynamic Tarim Basin

CLINICAL APPLICATION OF OPTICAL COHERENCE TOMOGRAPHY FOR IMAGING ANTERIOR SEGMENT OF EYE

在线全文

学校读者我要写书评

暂无评论

CLINICAL APPLICATION OF OPTICAL COHERENCE TOMOGRAPHY FOR IMA...

第十八届国际眼科研究大会

作者： Jianhua *** Palmer Eye Institute university of miami Miller School of Medicine miami FL.

＜正＞With the technological advancements in optical coherence tomography（OCT）,ultra-high resolution with high speed data acquisition can be achieved for imaging the anterior segment of the *** applications using OC...

关键词：

Targeting Angiogenesis and Apoptosis in Breast Cancer

在线全文

cnki会议

学校读者我要写书评

暂无评论

Targeting Angiogenesis and Apoptosis in Breast Cancer

第三届中国肿瘤学术大会

作者： Shou - Ching Tang MD, PhD, university of miami

＜正＞ Angiogenesis plays art important role in the pathogenesis, tumor progression and metastasis of breast cancer. A central regulator of angiogenesis is the vascular endothelia growth factor （VEGF） and its receptor （VEGFR） , which has emerged as the key target for anti - angiogenic cancer therapy. Several strategies designed to inhibit the tumor angiogenic pathway have been developed, including monoclonal antibodies against the VEGF, small molecule tyrosine kinase inhibitors of VEGFR, VEGF - binding soluble VEGFRs （VEGF -Trap） and ribozymes that down -regulate VEGFR expression. Bevacizumab is

关键词：

Phylogeography of regional fauna on the Tibetan Plateau: A review

在线全文

cnki会议

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2009年第7期19卷 789-799页

作者： Shujuan Yanga, Hailiang Dongb,c, Fumin Lei d a State Key Laboratory of Geological Processes and Mineral Resources, China university of Geosciences, Beijing 100083, China b Geomicrobiology Laboratory, China university of Geosciences, Beijing 100083, China c Department of Geology, miami university, Oxford, OH 45056, USA d Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China [a]State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China [b]Geomicrobiology Laboratory China University of Geosciences Beijing 100083 China [c]Department of Geology Miami University Oxford OH 45056 USA [d]Institute of Zoology Chinese Academy of Sciences Beijing 100101 China

The studies of uplift and glaciations of the Tibetan Plateau are summarized, and a series of recent case studies of the endemic species based on DNA sequences are detailed. In general, these molecular data show that all the organisms originated from Early Pliocene to Late Miocene, and then multi-stages of divergence/speciation occurred within each taxa following their original occupation on the plateau, mainly as a result of periodic glacial cycles and geographic isolation. The regional fauna may have undergone several range contractions and expansions during the Pleistocene glaciations. However, the population expansion and refugia may vary in space, time, and extent. The regional fauna of the Tibetan Plateau may be combinations of ancient movement from adjacent zoogeographical regions, speciation in situ, and postglacial colonization from adjacent areas. Geomorphic and climatic changes on the plateau definitely have a remarkable influence on the regional and adjacent biogeographic patterns, and the mechanism is very complex.

关键词： Divergence Refugia Postglacial colonization Phylogeography Regional fauna Tibetan Plateau

Bonding Characteristics of the Intermetallic Compound Al_3Ti+Cr

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 1996年第3期12卷 180-184页

作者： Senying LIU Rongze HU Dongliang ZHAO and Chongyu WANG (Central Iron and Steel Research Institute, Beijing 100081, China)Ping LUO (National Research Center for Certified Material, Beijing 100013, China)Zhongjie PU (Florida International university, miami NATL RES CTR CERTIFIED MAT BEIJING 100013PEOPLES R CHINA FLORIDA INT UNIV MIAMIFL 33199

Based on our structural model and a tight-binding Hamiltonian the eIectronic structure has been calculated by use of a recursion method (RM) for two models of the tetragonal DO22 and the cubic Ll2 crystal structures in Al3Ti+Cr for contrast, from which bonding characteristics have been discussed. The results for the interaction energy (IE) show that Cr prefers to replacing Al site. Cr partly replacing Al can change the IE between the atoms and make the constriction of lattice constant c and the elongation of lattice constant a for the DO22 and thereby may induce the change of crystal structure from DO22 to L12. The results for bond order integral (BOI) and IE between the atoms also show that the strong (110) directional Cr-Ti bondings are ***, Al3Ti-base intermetallic compounds with addition of the Cr atom still remain brittle.

关键词： Ti II Al Bonding Characteristics of the Intermetallic Compound Al3Ti+Cr Res

Corrosion behavior of tungsten coated SS316 as bipolar plates for PEMFC

在线全文

学校读者我要写书评

暂无评论

Corrosion behavior of tungsten coated SS316 as bipolar plate...

第九届全国氢能学术会议

作者： Y.Yang,L.J.Guo,H.T.Liu 1 Xi ’an Jiaotong university,China 2 university of miami,USA

A thin tungsten layer was coated on 316 stainless steels(SS316) by magnetron sputtering *** coated SS316 was investigated in simulated polymer electrolyte membrane fuel cell(PEMFC) environment,a solution with 0.1 M HSO and 2 ppm *** solution was kept at 80℃and was bubbled thoroughly either with hydrogen gas(to simulate PEMFC anode environment) or with pressurized air(to simulate PEMFC cathode environment) prior

关键词：

在线全文

cnki会议

学校读者我要写书评

暂无评论

火在生态系统中的作用

生态学杂志 1992年第1期 43-49页

作者：高(氵韦) 美国俄亥俄州迈阿密大学环境系

前言火对植被的影响是在近十多年来才被完全确认的。在二十世纪的大部分时间内,火常常被认为是破坏生态系统的非自然因子;然而,植被学家、人类学家、地理学家和其他许多学者都认为北美的土族印地安人和其他许多民族曾广泛地利用火作为... 详细信息

前言火对植被的影响是在近十多年来才被完全确认的。在二十世纪的大部分时间内,火常常被认为是破坏生态系统的非自然因子;然而,植被学家、人类学家、地理学家和其他许多学者都认为北美的土族印地安人和其他许多民族曾广泛地利用火作为土地管理的工具(Van-

关键词： fire fire suppression fire management ecosystem.

Non-syndromic X-linked deafness(DFN2)is caused by decreased functional mutations in PRPS1

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Non-syndromic X-linked deafness(DFN2)is caused by decreased ...

第八次全国医学遗传学学术会议(中华医学会2009年医学遗传学年会)

作者： YUAN Hui-Jun,LIU Xue- Zhong~*,LI Jian-Zhong,HAN Bing,CHENG Jing,WANG You-Qin~(**),CHEN Jing,LIU Yuqing~(**),DAI Pu,HAN Dong-Yi Institute Of Otolaryngology,Chinese PLA General Hospital,Beijing 100853,China * Department of Otolaryngology,university of miami, miami,FL 33136,USA * * Hearing Center,Guizhou Provincial People’s Hospital,GuiYang 550002,China

Hereditary nonsyndromic hearing loss(NSHL)is extremely *** the past decade,remarkable progress has been made towards determining the deafness-causing *** date,over 110 loci have been mapped for NSHL,and 47 deafness genes from these loci have been *** vast majority of cases of NSHL are associated with mutations in autosomal *** deafness is clinically and genetically a heterogeneous disorder accounting for about 5%of all congenital deafness,and for less than 2%of non-syndromic hearing *** first deafness-causing gene,POU3F4,was identified in a family with X-linked non-syndromic hearing loss in *** seven non-syndromic deafness loci(DFN2-8)have been mapped to the X chromosome over the last 15 years,the second X-linked deafness gene has not yet been *** DFN2 locus was mapped to Xq13-q24 and previously defined by three different *** age at detection of the hearing loss in affected males in these families varied from birth to 20 years of age,indicating that DFN2 can cause either congenital or post-lingual *** the present study,we ascertained a five generation Chinese family characterized by X-linked postlingual,progressive,non-syndromic sensorineural hereditary hearing impairment. We mapped the disease locus to a 5.4 cM region on Xq22 between DXS8020 and DXS8055 overlapping with the known DFN2 *** in the phosphoribosyl pyrophosphate synthetase 1(PRPS1)gene were found in all identified DFN2 families, demonstrating that PRPS1 is likely the gene responsible for DFN2 deafness.

关键词： DFN2 X-linked hearing impairment PRPS1 mutation