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Cell Research 2005年第7期15卷 539-547页

作者： Peihsien TANG department of Cell Biology Institute of Basic Medical sciences Academy of Military Medical sciences Beijing 100850 china

ABSTRACTHuman placenta-derived mononuclear cells (MNC) were isolated by a Percoll density gradient and cultured in mesen-chymal stem cell (MSC) maintenance medium. The homogenous layer of adherent cells exhibited a typical fibroblast-like morphology, a large expansive potential, and cell cycle characteristics including a subset of quiescent cells. In vitrodifferentiation assays showed the tripotential differentiation capacity of these cells toward adipogenic, osteogenic andchondrogenic lineages. Flow cytometry analyses and immunocytochemistry stain showed that placental MSC was ahomogeneous cell population devoid of hematopoietic cells, which uniformly expressed CD29, CD44, CD73. CD105,CD166, laminin, fibronectin and vimentin while being negative for expression of CD3., CD3., CD45 and α-smoothmuscle actin. Most importantly, immuno-phenotypic analyses demonstrated that these cells expressed class I majorhistocompatibility complex (MHC-I), but they did not express MHC-II molecules. Additionally these cells could sup-press umbilical cord blood (UCB) lymphocytes proliferation induced by cellular or nonspecific mitogenic stimuli. Thisstrongly implies that they may have potential application in allograft transplantation. Since placenta and UCB arehomogeneous, the MSC derived from human placenta can be transplanted combined with hematopoietic stem cells(HSC) from UCB to reduce the potential graft -versus-host disease (GVHD) in recipients.

关键词： mesenchymal stem cells human placenta umbilical cord blood immune regulation.

CMC surfaces in the hyperbolic 3.space

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Chinese Science Bulletin 1998年第7期43卷 547-550页

作者： YU Zuhuan 1, 2 and LI Zhenqi 1, 3.1. Institute of Mathematics, Fudan university, Shanghai 20043., china 2. department of Mathematics,Sichuan Union university, Chengdu 610064, china 3. department of Mathematics, Nanchang university, Nanchang 3. nstitute of Mathemalics Fudan University Shanghai China department of Mathematics Sichuan Union University Chengdu China department of Mathematics Nanchang University Nanchang China

CMC-H surfaces satisfying H≥1 are studied. It is proved that these surfaces possess a natural representation which is a generalization of the Bryant’s result.

关键词： hyperbolic space CMC surface Weierstrass representation.

Constraints on Characteristics and Distribution of Gas Hydrate and Free Gas Using Broad-Band Processing of Three-Dimensional Seismic Data

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Journal of Ocean university of china 2024年第5期23卷 1233-1247页

作者： WANG Xiujuan ZHOU jilin LI Sanzhong LI Lixia LI Jie LI Yuanping WANG Linfei SU Pibo JIN Jiapeng GONG Zhi State Key Laboratory of Offshore Natural Gas Hydrate Beijing 100028China Frontiers Science Center for Deep Ocean Multispheres and earth System Key Laboratory of Submarine Geosciences and Prospecting TechniquesMOE and College of Marine GeosciencesOcean University of ChinaQingdao 266100China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdao 266237China CNOOC Research Institute Co. Ltd.Beijing 100028China CNOOC china Limited Shenzhen BranchShenzhen 518054China Guangzhou Marine Geological Survey China Geological SurveyGuangzhou 510000China

Gas hydrate drilling expeditions in the Pearl River Mouth Basin,South china Sea,have identified concentrated gas hydrates with variable ***,free gas and the coexistence of gas hydrate and free gas have been confirmed by logging,coring,and production tests in the foraminifera-rich silty sediments with complex bottom-simulating reflectors(BSRs).The broad-band processing is conducted on conventional three-dimensional(3.)seismic data to improve the image and detection accuracy of gas hydratebearing layers and delineate the saturation and thickness of gas hydrate-and free gas-bearing *** geophysical attributes extracted along the base of the gas hydrate stability zone are used to demonstrate the variable distribution and the controlling factors for the differential enrichment of gas *** inverted gas hydrate saturation at the production zone is over 40% with a thickness of 90 m,showing the interbedded distribution with different boundaries between gas hydrate-and free gas-bearing ***,the gas hydrate saturation value at the adjacent canyon is 70%,with 3.-m-thick patches and linear *** lithological and fault controls on gas hydrate and free gas distributions are demonstrated by tracing each gas hydrate-bearing ***,the BSR depths based on broad-band reprocessed 3. seismic data not only exhibit variations due to small-scale topographic changes caused by seafloor sedimentation and erosion but also show the upward shift of BSR and the blocky distribution of the coexistence of gas hydrate and free gas in the Pearl River Mouth Basin.

关键词： gas hydrate free gas shift of BSR broad-band processing

Boron nitride microribbons strengthened and toughened alumina composite ceramics with excellent mechanical,dielectric,and thermal conductivity properties

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Journal of Advanced Ceramics 2024年第4期13卷 496-506页

作者： jilin Wang Dongping Lu Weiping Xuan Yuchun Ji Ruiqi Chen Shaofei Li Wenbiao Li Wenzhuo Chen Shilin Tang Guoyuan Zheng Fei Long Guangxi Key Laboratory of Optical and Electronic Materials and Devices Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of ResourcesSchool of Materials Science and EngineeringGuilin University of TechnologyGuilin 541004China Key Laboratory of New Processing Technology for Nonferrous Metals and Materials of Ministry of Education Guilin University of TechnologyGuilin 541004China School of Materials Science and Engineering Peking UniversityBeijing 100871China department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityKowloon 999077Hong KongChina

Aluminum oxide(Al_(2)O_(3.)ceramics have been widely utilized as circuit substrates owing to their exceptional *** this study,boron nitride microribbon(BNMR)/Al_(2)O_(3.composite ceramics are prepared using spark plasma sintering(SPS).This study examines the effect of varying the amount of toughened phase BNMR on the density,mechanical properties,dielectric constant,and thermal conductivity of BNMR/Al_(2)O_(3.composite ceramics while also exploring the mechanisms behind the toughening and increased thermal conductivity of the fabricated *** results showed that for a BNMR content of 5 wt%,BNMR/Al_(2)O_(3.composite ceramics displayed more enhanced characteristics than pure Al_(2)O_(3.*** particular,the relative density,hardness,fracture toughness,and bending strength were 99.95%±0.025%,3..11±1.5 GPa,5.42±0.21 MPa·m^(1/2),and 3.5±2.5 MPa,*** values represent increases of 0.76%,70%,3.%,and 25%,respectively,compared with the corresponding values for pure Al_(2)O_(3.***,during the SPS process,BNMRs are subjected to high temperatures and pressures,resulting in the bending and deformation of the Al_(2)O_(3.matrix;this leads to the formation of special thermal pathways within *** dielectric constant of the composite ceramics decreased by 25.6%,whereas the thermal conductivity increased by 45.6%compared with that of the pure Al_(2)O_(3.*** results of this study provide valuable insights into ways of enhancing the performance of Al_(2)O_(3.-based ceramic substrates by incorporating novel BNMRs as a second *** improvements are significant for potential applications in circuit substrates and related fields that require high-performance materials with improved mechanical properties and thermal conductivities.

关键词： boron nitride microribbons/aluminum oxide(BNMRs/Al_(2)O_(3.)composite ceramics boron nitride microribbon(BNMR) spark plasma sintering(SPS) strengthening and toughening thermal conductivity

Online uniform machine covering with the known largest size

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Progress in Natural Science:Materials International 2007年第11期17卷 1271-1278页

作者： Cao Shunjuan1,2 and Tan Zhiyi1,3.1. department of Mathematics, Zhejiang university, Hangzhou 3.0027, china 2. department of Mathematics, Zhejiang Forestry university, Hangzhou 3.13.0, china 3. State Key Laboratory of CAD & CG, Zhejiang university, Hangzhou 3.0027, china) department of Mathematics Zhejiang University Hangzhou 310027 China department of Mathematics Zhejiang Forestry University Hangzhou 311300 China State Key Laboratory of CAD and CG Zhejiang University Hangzhou 310027 China

This paper investigates the semi-online scheduling problem with the known largest size on two uniform machines. The objective is to maximize the minimum machine completion time. Both lower bounds and algorithms are given. Algorithms are optimal for the majority values of s≥1, where s is the speed ratio of the two machines. The largest gap between the competitive ratio and the lower bound is about 0.064. Moreover, the overall competitive ratio 2 matches the overall lower bound.

关键词： scheduling and covering uniform machine design and analysis of algorithm online competitive ratio

Microcracks and Overpressure-Induced Fractures

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Global Geology 2001年第2期6卷 135-138页

作者： Ahmed M. Al-QAHTANI(College of earth sciences, jilin university, {3., 130061, P.R. china) College of earth sciences Jilin University Changchun 130061 P.R. China

The microfractures and natural fractures studies have a great significance in the hydrocarbon accumulation exploration and can be a good supporter for wide geophysical study on the major structures. This paper is a brief review on microcracks and overpressure-induced fracture. It is to discuss different views on the mechanism of fractures in the subsurface of the earth.

关键词： overpressure- induced fracture, microcracks, Geothermal, non mineralic- lined microfractures

CENOZOIC VOLCANISM AND GEOTHERMAL RESOURCES IN NORTHEAST china

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Chinese Geographical Science 2001年第2期11卷 150-154页

作者： WANG Xi-kui1, QIU Shan-wen2, SONG Chang-chun2, KULAKOV Aleksey3. TASHCHI Stepan3. MYASNIKOV Evgeny3.(1.College of earth sciences, jilin university,{3. 13.012,P.R.china 2.{3. Institute of Geography, the Chinese Academy of sciences,{3. College of earth sciences Jilin University Changchun P. R. China changchun Institute of Geography the Chinese Academy of Sciences Changchun P. R. China Pacific Institute of Geography Far East Science Center of the Russian Academy of Sciences Vladivostok Russia

This paper is concentrated on Cenozoic volcanism and geothermal resources in Northeast china. There are a lot of Cenozoic volcanoes, a large area of volcanic rocks, a large number of active faults and rich geothermal resources in Northeast china. The time and space characteristics of Cenozoic volcanism and the space distribution characters of hot springs and high geothermal flux regions in Northeast china are described and discussed on the basis of geological, geothermal, drilling and volcanological data. It is revealed that the hot springs and high geothermal flux regions are related to the Cenozoic volcanism, rifting and faulting in Northeast china. It is especially emphasized that the hot springs and high geothermal anomaly areas are controlled by active deep faults. It is proposed that the Cenozoic volcanism regions, rift basins, active fault belts, activated plate suture zones and large earthquake occurrence points are the best areas for prospecting geothermal resources. The geothermal resources in younger volcanic zones are richer than those in older volcanic belts. The hot springs and active or activated faults might be a very good clue for looking for geothermal resources.

关键词： volcanism active faults geothermal resources Northeast china

Transitivity, mixing and chaos for a class of set-valued mappings

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Science china Mathematics 2006年第1期49卷 1-8页

作者： LIAO Gongfu, WANG Lidong & ZHANG Yucheng Institute of Mathematics, jilin university, changchun 13.012, china Institute of Nonlinear Information Technology, Dalian Nations {3., Dalian 116600, china department of Mathematics, {3. of Science and Technology of china, Hefei 23.026, china Institute of Mathematics Jilin University Changchun China Institute of Nonlinear Information Technology Dalian Nations University Dalian China department of Mathematics University of Science and Technology of China Hefei China

Consider the continuous map f : x → X and the continuous map f of K,(X) into itself induced by f, where X is a metric space and K(X) the space of all non-empty compact subsets of x endowed with the Hausdorff metric. According to the questions whether the chaoticity of f implies the chaoticity of f posed by Roman-Flores and when the chaoticity of f implies the chaoticity of f posed by Fedeli, we investigate the relations between f and f in the related dynamical properties such as transitivity, weakly mixing and mixing, etc. And by using the obtained results, we give the satisfied answers to Roman-Flores's question and Fedeli's question.

关键词： set-valued mapping, transitivity, weak mixing, mixing, chaos.

Zircon SHRIMP U-Pb geochronology and petrogenesis of the plagiogranites from the Lagkor Lake ophiolite,Gerze,Tibet,china

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Chinese Science Bulletin 2007年第5期52卷 651-659页

作者： ZHANG YuXiu1,2, ZHANG KaiJun1,3. LI Bing1,2, WANG Yang1,2, WEI QingGuo1,2 & TANG XianChun1,2 1 Key Laboratory of Marginal Sea Geology, Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 510640, china 2 Graduate university, Chinese Academy of sciences, Beijing 10003., china 3.department of earth sciences, Nanjing university, Nanjing 210093. china Key Laboratory of Marginal Sea Geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate university Chinese Academy of Sciences Beijing China department of earth sciences Nanjing University Nanjing China

地关系与 petrographical 一起， petrological ，和 geochemicalcharacteristics ，和锆石人口，显示从在 Bangong-Nujiang 缝术地区的 Lagkor Lakeophiolite 的 plagiogranites (～ Gerze 县的 20 km 南方，中央西藏，中国)，由在海洋的外壳的运输期间的可锻的砍源于含水的斑粝岩的 anatexis 。因此，这种 plagiogranite 比传播海洋的外壳晚对或很少同时代。锆石虾 166 ±使 2.5 妈变老因为 plagiogranites 显示海洋的盆在中间的侏罗记在 Bangong-Nujiang 地区的西方的部分存在。

关键词：西藏改则县拉果错湖泊蛇绿岩斜长花岗岩锆SHRIMP U-Pb地质年代岩石成因

Geochemical research on C-O and Sr-Nd isotopes of mantle-derived rocks from Shandong Province, china

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Science china earth sciences 2004年第2期47卷 171-180页

作者： LIU Jianming, ZHANG Hongfu, SUN Jinggui & YE Jie1. Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 100029, china 2. School of earth Science, {3., changchun 130061, china Correspondence should be addressed to Liu Jianming (email: jmliu@***) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China School of earth Science Jilin University Changchun China

This paper presents systematic studies on the C-O and Sr-Nd isotopic compositions for Cretaceous Badou carbonatites, Fangcheng basalts, and Jiaodong lamprophyres and Paleozoic Mengyin kimberlites in Shandong Province, china. Paleozoic kimberlites have normal and uniform C-O isotopic compositions with δ13. and δ18O in the range of -4.8‰--7.6‰ and +9.9‰-+13.2‰, respectively. However, Cretaceous three different types of mantle-derived rocks have quite different C-O isotopic compositions, indicating that the mantle sources are probably partially contaminated with organic carbon-bearing crustal materials. These Cretaceous rocks show uniform and EMII-like Sr-Nd isotopic compositions and also indicate that the mantle sources were affected by recycled crustal materials. Comparative studies of C-O and Sr-Nd isotopes reveal that the lithospheric mantle beneath the eastern North china Craton had different isotope characteristics in the Paleozoic, the early Cretaceous, and the Tertiary time. This demonstrates that the lithospheric mantle beneath the region underwent at least twice reconstructions since the Paleozoic. Available data imply that the first reconstruction mainly happened during the Triassic-Jurassic time with gradual changes and the second in the Cretaceous with abrupt changes. Results also show that the early Cretaceous (especially at 120-13. Ma) was perhaps the key period leading to the dramatic change of the Mesozoic geodynamics on the eastern North china Craton.

关键词： mantle-derived rocks, carbonate minerals, C-O isotope, Sr-Nd isotope, lithospheric mantle, Shandong.