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THE GENERALIZED REFLEXIVE SOLUTION FOR A CLASS OF MATRIX EQUATIONS (AX-B,XC=D)

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Acta Mathematica Scientia 2008年第1期28卷 185-193页

作者：李范良胡锡炎张磊 Institute of Mathematics and Physics School of SciencesCentral South University of Forestry and Technology College of Mathematics and Econometrics Hunan University

In this article, the generalized reflexive solution of matrix equations （AX = B, XC = D） is considered. With special properties of generalized reflexive matrices, the necessary and sufficient conditions for the solvability and the general expression of the solution are obtained. Moreover, the related optimal approximation problem to a given matrix over the solution set is solved.

关键词： Matrix equations generalized reflexive matrix optimal approximation

Thermodynamic Behavior of Manganese and Phosphorus between Liquid Iron and CaO-MgO-SiO_2.Al_2._3.Fe_tO-MnO-P_2._5 Slags

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Journal of University of science and Technology Beijing 2001年第3期8卷 171-176页

作者： Bo Song, Seon-Hyo Kim, Jinghong Mao, Qing Lin Metallurgy school, University of science and Technology Beijing, Beijing 100083. {2. Department of {3.s science & engineering, Pohang University of science & Technology, Pohang 790-784, Korea {3. S Univ Sci & Technol Beijing Met Sch Beijing 100083 Peoples R China Pohang Univ Sci & Technol Dept Mat Sci & Engn Pohang 790784 South Korea Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

The thermodynamic behavior of manganese and phosphorus between liquid iron and CaO-MgO-SiO2.Al2.3.FetO-MnO-P2.5 ladle slag system was addressed by investigating the thermodynamic equilibria between liquid iron containing Mn and P and the ladle slag at 1873.K. The Mn distribution ratio L-Mn increases with increasing FetO content and decreasing the basicity ((%CaO + %MgO)/(%SiO2.+ %Al2.3.+ %P2.5)) in slag, while the P distribution ratio Lp seems to be increased as FetO content and the basicity increases. The values of L-Mn and L-p decrease by the addition of Al2.3.into slag. The expression of the dependence of L-Mn and L-p on the basicity and FetO content in slag was obtained.

关键词： manganese phosphorus liquid iron ladle slag thermodynamic behavior

Formation and evolution mechanisms of large-clusters during rapid solidification process of liquid metal Al

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science china(Physics,Mechanics & Astronomy) 2005年第1期48卷 101-112页

作者： LIU Rangsu, DONG Kejun, LIU Fengxiang, ZHENG Caixing, LIU Hairong & LI Jiyong Department of Applied Physics, Hunan University, changsha 410082. china College of {2.s science and engineering, Hunan University, changsha 410082. china College of Chemistry and Chemical engineering, Hunan University, changsha 410082. china 1. Department of Applied Physics Human University 410082 Changsha China 2. College of materials science and {2. Hunan University 410082 Changsha China 3. College of Chemistry and Chemical engineering Hunan University 410082 Changsha China

A molecular dynamics simulation study has been performed for the formation and evolution characteristics of nano-clusters in a large-scale system consisting of 400000 atoms of liquid metal Al. The center-atom method combined with pair-bond analysis technique and cluster-type index method (CTIM) has been applied here to describe the structural configurations of various basic clusters. It is demonstrated that both the 1551 bond-type and the icosahedral cluster (12.0 12.0) constructed by 1551 bond-types are dominant among all the bond-types and cluster-types, respectively, in the system and play a critical role in the microstructure transitions of liquid metal Al. The nano-clusters (containing up to 150 atoms) are formed by the combination of some middle and small clusters with distinctly different sizes, through mutual competition by unceasing annex and evolution in a seesaw manner (in turn of obtaining and losing),which do not occur as the multi-shell structures accumulated with an atom as the center and the surrounding atoms are arranged according to a certain rule. This is the essential distinction of nano-cluster in liquid metal from those obtained by gaseous deposition, ionic spray methods, and so on. Though the nano-clusters differ from each other in shape and size, all of them possess protruding corners that could become the starting points of various dendrite structures in the solidification processes of liquid metals.

关键词： liquid metal, solidification process, large-cluster configuration, evolution mechanism, computer simulation.

热处理条件对氧化石墨结构和导电性能的影响(英文)

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新型炭材料 2004年第2期19卷 92-96页

作者：肖敏杜续生孟跃中龚克成中山大学理工学院广东广州510275 中国科学院广州化学研究所广东广州510650 华南理工大学材料学院广东广州510641

　氧化石墨是石墨的氧化产物,由于它的碳层表面引入了很多极性功能团,使得很多分子都能够嵌入其层间形成纳米复合物,但也正是这些功能团使得它散失了石墨良好的导电性。为了考察氧化石墨受热处理后还原的可能性,通过X 射线衍射、扫描电... 详细信息

　氧化石墨是石墨的氧化产物,由于它的碳层表面引入了很多极性功能团,使得很多分子都能够嵌入其层间形成纳米复合物,但也正是这些功能团使得它散失了石墨良好的导电性。为了考察氧化石墨受热处理后还原的可能性,通过X 射线衍射、扫描电镜、红外光谱分析以及元素分析等手段研究了氧化石墨在不同热处理条件下的结构变化。研究发现热处理时的升温速度对氧化石墨的结构影响很大,快速升温时,氧化石墨迅速分解,发生膨胀形成类似于膨胀石墨的含有丰富的50nm至5μm左右孔洞的一种结构;而当缓慢升温时,氧化石墨随着热处理温度的升高,逐渐恢复成类似于石墨的结构,同时电导率也随热处理温度的升高而提高,当热处理温度高于180℃时,电导率大于1S/cm。这些结果表明利用氧化石墨作为前驱体,通过先制备聚合物/氧化石墨纳米复合物后经热处理来得到导电性的聚合物/碳纳米复合材料是可行的。

关键词：热处理条件氧化石墨结构导电性能热解

Effect of aging on the mechanical properties and corrosion susceptibility of an Al-Cu-Li-Zr alloy containing Sc

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Rare Metals 2008年第2期27卷 146-152页

作者： LIANG Wenjie PAN Qinglin HE Yunbin LI Yunchun ZHOU Yingchun LU Congge school of materials {2. and {3. Central South University Changsha 410083 China

The effects of aging on the microstructure, mechanical properties, intergranular corrosion, and exfoliation corrosion of an Al-3.5Cu-1.5Li-0.2.（Sc ＋ Zr） alloy have been investigated. The results show that the alloy has the character of age hardening, and the major phase of precipitation and strengthening is the T1 phase. The aging temperature and aging time have a significant effect on the amount and distribution of the T1 phase. The proper artificial single-aging treatment of the alloy is at 160℃ for 40 h. The intergranular corrosion and exfoliation corrosion of the alloy are caused by the anodic dissolution of the T1 phase and the precipitate-free zone （PFZ）. With increasing the aging time to overaged, the T1 phase coarsens, and the PFZ widens, leading to an increase in the susceptibility to intergranular corrosion and exfoliation corrosion.

关键词： Al-Li alloys aging microstructure T1 phase corrosion

Organic anion transporting polypeptide-1B1 haplotypes in Chinese patients

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Acta Pharmacologica Sinica 2007年第10期28卷 1693-1697页

作者： Lin-yong XU~2.Yi-jing HE~3.Wei ZHANG~3.Sheng Deng~4,Qing LI~3.Wei-xia ZHANG~3.Zhao-qian LIU~3.Dan WANG~3.Yuan-feiHUANG~3.Hong-hao ZHOU~(3.5),Zhen-qiu SUN~(2.5)~2.Department of Epidemic and Health Statistics,{3. of Public Health,central {2. University,changsha 410078,china,~3.Pharmaeoge-netics Research Institute,Institute of Clinical Pharmacology,central {2. University,changsha 410078,china ~4 Affiliated XiangyaHospital of central {2. University,changsha 410078,china ment of Epidemic and Health Statistics School of Public Health Central South University Changsha 410078 China. xybms@***.

Aim:To detect 3.8G>A and 52.T>C variant alleles in the organic anion trans-porting polypeptide-1B 1 （OATP 1B 1,encoding gene SLCO 1B 1） ***:One hundred and eleven healthy volunteers were screened for OATP1B 1 alleles inour ***-restriction fragment length polymorphism was used to identifythe 3.8G>A polymorphism and a 1-step tetra-primer method was developed forthe determination of 52.T>C ***:The frequencies of the 3.8G>Aand 52.T>C variant alleles in the Chinese population were 73.4% and 14.0%,*** frequencies of the SLCO1B1*1b and*15 haplotypes were59.9% and 14.0%,***:The SLCO1B1*1b and SLCO1B1*15variants are relatively common in the Chinese *** frequencies aresimilar to that in the Japanese,but significantly different from that in Caucasiansand blacks.

关键词： organic anion transporting polypeptide-1B1 3.8G>A 52.T>C genotyping Chinese patients

Hydroalumination of diazo and azido compounds:An Al-H addition to end-on nitrogen of substrates

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science china Chemistry 2010年第9期53卷 1970-1977页

作者： CHU ChenHui1,YANG Ying1,2.& ZHU HongPing1 1State Key Laboratory of Physical Chemistry of Solid Surfaces National engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-Esters College of Chemistry and Chemical engineering,Xiamen University,Xiamen 3.1005,{2. 2.3. of Chemistry and Chemical engineering,central south University,changsha 4.0083.{2. 1. State Key Laboratory of Physical Chemistry of Solid Surfaces National engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-Esters College of Chemistry and Chemical engineering Xiamen University Xiamen 361005 China2. School of Chemistry and Chemical Engineering Central South University Changsha 410083 China

This paper reports the reactions of a monomeric aluminum dihydride LAlH2.L = HC[C(Me)N(Ar)]2.Ar = 2.6-i-Pr2.6H3. with diazo,azido,and terminal alkyne *** reaction of LAlH2.with N2.H(SiMe3. and N3.1-Ad) occurred through an Al-H addition to end-on nitrogen to yield respective compounds LAl[N(H)N = CH(SiMe3.]2.1) and LAl[N(H)N=N(1-Ad)]2.2.,while the reaction of LAlH2.with PhC≡CH occurred through a stepwise deprotonation to yield LAlH(C≡CPh)(5) and LAl-(C≡CPh)2.6),respectively.2.further reacted by N2.release to yield LAl[NH(1-Ad)][N(H)N=N(1-Ad)](3. and LAl[NH-(1-Ad)]2.4) upon the increased temperature *** 1-6 have been fully characterized,revealing novel reactivity patterns of LAlH2.toward different substrates under the steric influence from the bulky L ligand at Al.

关键词： hydroalumination bulky aluminum hydride multiple-bond molecule Al–H addition

Identification of Genes Related to Nasopharyngeal Carcinoma with the Help of Pathway-based Networks

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Acta Biochimica et Biophysica Sinica 2006年第12期38卷 900-910页

作者： Hui LI~1 Cai-Ping REN~1* Xiao-Jun TAN~2.Xu-Yu YANG~1 Hong-Bo ZHANG~1 Wen ZHOU~1 Kai-Tai YAO~1 1 Cancer Research Institute,Xiangya school of Medicine,central {2. University,changsha 410078,china 2.Reproductive and Stem Cell engineering Institute,Xiangya school of Medicine,central {2. University,changsha 410078,china CancerResearchInstitute XiangyaSchoolofMedicineCentralSouthUniversityChangsha410078China ReproductiveandSternCellengineeringInstitute XiangyaSchoolofMedicineCentralSouthUniversityChangsha410078China

cDNA microarray is a powerful tool to analyze simultaneously the expression levels of tens ofthousands of *** with normal nasopharynx (NP) tissues,2.10 genes were highly differentiallyexpressed in nasopharyngeal carcinoma (NPC) tissues detected by cDNA *** signal pathwayis widely used to describe the complex relationship between genes,a pathway-based network was con-structed to visualize the connection between the genes obtained from microarray data in this *** the targeted genes that may have more important influence on this gene network with statisticalmethods and found that some genes might have significant influence on this network,especially Ras-relatednuclear protein (RAN),carboxyl ester lipase (CEL),v-rel reticuloendotheliosis viral oncogene homolog A(RELA) *** verify the results from pathway-based selection,reverse transcription-polymerase chainreaction (RT-PCR) and real-time RT-PCR were performed to detect the expression levels of RAN,CEL andRELA genes and it was found that the RAN and CEL genes were significantly up-regulated in more than 80%of NPC *** further elucidate the function of the RAN gene,RAN expression was specifically sup-pressed in a 5-8F NPC cell line by RNA interference (RNAi).As expected,the depletion of RAN couldeffectively block the proliferation of tumor ***,our study may open up a new way to analyze thevast microarray data.

关键词： nasopharyngeal carcinoma microarray real-time PCR RNA interference Ras-related nuclear protein (RAN)

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高速铁路连续结合梁的响应分析

铁道学报 2002年第6期24卷 84-88页

作者：张晔芝中南大学土木建筑学院湖南长沙410075

我国高速铁路中将经常采用 (40 +5 0 +40 ) m双线连续结合梁桥。笔者受设计部门的委托 ,通过空间有限元分析计算 ,对该桥初步设计方案的响应 ,包括剪滞问题、弯剪复合问题、偏载下的扭转问题、混凝土徐变和活载的横向分布对应力的影响... 详细信息

我国高速铁路中将经常采用 (40 +5 0 +40 ) m双线连续结合梁桥。笔者受设计部门的委托 ,通过空间有限元分析计算 ,对该桥初步设计方案的响应 ,包括剪滞问题、弯剪复合问题、偏载下的扭转问题、混凝土徐变和活载的横向分布对应力的影响问题等作了研究。

关键词：响应分析高速铁路连续结合梁空间有限元法铁路桥