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THE INVERSE PROBLEM OF CENTROSYMMETRICMATRICES WITH A SUBMATRIX CONSTRAINT

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Journal of Computational Mathematics 2004年第4期22卷 535-544页

作者： Zhen-yunPeng Xi-yanHu leizhang DepartmentofMathematics HunanUniversityofScienceandTechnologyXiangtan411201China (CollegeofMathematicsandEconometrics HunanUniversityChangsha410082China

By using Moore-Penrose generalized inverse and the general singular value decomposition of matrices, this paper establishes the necessary and sufficient conditions for the existence of and the expressions for the centrosymmetric solutions with a submatrix constraint of matrix inverse problem AX = B. In addition, in the solution set of corresponding problem, the expression of the optimal approximation solution to a given matrix is derived.

关键词： Centrosymmetric matrix Inverse problem Matrix norm Optimal approximation

Synthesis of Iminosugar-Containing KRN7000 Analogues

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Chinese Journal of Chemistry 2017年第6期35卷 1001-1008页

作者： leizhang Xin-Shan Ye State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Road No. 38 Beijing 100191 China

Three new iminosugar-containing KRN7000 （also referred to as α-GalCer） analogues were designed and syn- thesized. In the design, the galactose moiety of KRN7000 was replaced by iminosugars and the iminosugar struc- tures were connected with ceramide in different manners with a C-glycosidic bond instead of the O-glycosidic bond. To our knowledge, this is the first report in which iminosugars are incorporated in KRN7000 structure modifica- tions. The synthetic compounds were evaluated for their ability to stimulate cytokine release. The results may benefit better understanding of structure-activity relationships and facilitate future design of more KRNT000 derivatives.

关键词： KRN7000 analogue glycolipid a-GalCer iminosugar synthesis

THE NEAREST BISYMMETRIC SOLUTIONS OF LINEAR MATRIX EQUATIONS

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Journal of Computational Mathematics 2004年第6期22卷 873-880页

作者： Zhen-yunPeng Xi-yanHu leizhang DepartmentofAppliedMathematics HunanUniversityofScienceandTechnologyXiangtan411201China CollegeofMathematicsandEconometrics HunanUniversityChangsha410082China

The necessary and sufficient conditions for the existence of and the expressions for the bisymmetric solutions of the matrix equations (Ⅰ)A1X1B1+A2X2B2+^…+AkXkBk=D，(Ⅱ)A1XB1+A2XB2+…+AkXBk=D and (Ⅲ) (A1XB1，A2XB2,…,AkXBk)=(D1,D2,…,Dk) are derived by using Kronecker product and Moore-Penrose generalized inverse of matrices. In addition, in corresponding solution set of the matrix equations, the explicit expression of the nearest matrix to a given matrix in the Frobenius norm is given. Numerical methods and numerical experiments of finding the neaxest solutions axe also provided.

关键词： Bisymmetric matrix Frobenius norm Kronecker product Matrix equation Matrix nearness problem Moore-Penrose generalized inverse

THE INVERSE PROBLEM FOR PART SYMMETRIC MATRICES ON A SUBSPACE

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Journal of Computational Mathematics 2003年第4期21卷 505-512页

作者： Zhen-yunPeng Xi-yanHu leizhang DepartmentofMathematics LoudiTeachersCollegeLoudi417000China CollegeofMathematicsandEconometrics HunanUniversityChangsha410082China

In this paper, the following two problems are considered:Problem Ⅰ. Given S∈E Rn×p,X,B 6 Rn×m, find A ∈ SRs,n such that AX = B, where SR8,n = {A∈ Rn×n|xT(A - AT) = 0, for all x ∈ R(S)}.Problem Ⅱ. Given A* ∈ Rn×n, find A ∈ SE such that ||A-A*|| = minA∈sE||A-A*||, where SE is the solution set of Problem Ⅰ.The necessary and sufficient conditions for the solvability of and the general form of the solutions of problem Ⅰ are given. For problem Ⅱ, the expression for the solution, a numerical algorithm and a numerical example are provided.

关键词： Part symmetric matrix Inverse problem Optimal approximation.

Porphyrins in Reverse Micelles: the Side-chain Length and the Triplet-state Lifetime

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Chinese Chemical Letters 2003年第8期14卷 844-847页

作者： JunHuaYU YuXiangWENG XueSongWANG leizhang BaoWenZHANG YiCAO TechnicalInstituteofPhysicsandChemistry ChineseAcademyofSciencesBeijing100101 InstituteofPhysics ChineseAcademyofSciencesBeijing100080

Using bis(2-ethylhexyl) sodium sulfosuccinate (AOT) as surfactant, two amphiphilic porphyrin terminated with imidazole were studied in AOT/iso-octane/water reverse micelles, intending to mimic the relationship between... 详细信息

关键词： Porphyrin triplet-state lifetime reverse micelle.

Synthesis of a New Polyoxometalate Loaded Stearic Acid Nanoparticles

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Chinese Chemical Letters 2004年第10期15卷 1255-1257页

作者： YongYANG leizhang WeiFAN XiaoHongWANG BinLI JingFuLIU DepartmentofChemistry NortheastNormalUniversityChangchun130024

The stearic acid nanoparticles loaded polyoxometalate K6[?-(CpTi)2SiW10O38] [(CpTi)2SiW10] have been prepared and structurally characterized by elemental analysis, IR spectra. The particle size was estimated by transition electron microscope and zatesizer instrument. The result showed that the polyoxometalate retained the parent structure after encapsulation by stearic acid nanoparticles.

关键词： Polyoxometalate stearic acid nanoparticles preparation.

Aluminum-activated Oxalate Secretion does not Associate with Internal Content among Some Oxalate Accumulators

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Journal of Integrative Plant Biology 2008年第9期50卷 1103-1107页

作者： Jian Li Yang leizhang Shao Jian Zheng State Key Laboratory of Plant Biochemistry and Physiology College of Life Sciences Zhejiang University Hangzhou 310058 China Department of Biology College of Food Science and Biotechnology Engineering Zhejiang Gongshang University Hangzhou 310035 China College of Environmental and Resource Sciences Zhejiang University Hangzhou 310029 China

Although aluminum （AI）-activated secretion of oxalate has been considered to be an important AI-exclusion mechanism, whether it is a general response in oxalate accumulators and related to oxalate content in roots are still not clear. Here, we examined the oxalate secretion and oxalate content in some oxalate accumulators, and investigated the role of oxalate secretion in AI resistance. When oxalate content in amaranth roots was decreased by about 50% with the increased ratio of NH4^＋-N to NO3^- -N in nutrient solution, the amount of AI-activated oxalate secretion still remained constant. There was no relationship between the content of the water soluble oxalate in four species of oxalate accumulators and the amount of the AI-activated oxalate secretion in roots. Furthermore, oxalate secretion is poorly associated with AI resistance among these species. Based on the above results, we concluded that although all of the oxalate accumulators tested could secrete oxalate rapidly, the density of anion channels in plasma membrane may play a more important role in AI-activated oxalate secretion.

关键词： aluminum toxicity Amaranthus anion channel oxalate accumulator oxalate secretion

The effects of L-arginine on C-Myc and PONA expression in hearts of rat abdominal aortic coarctation model

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中国组织化学与细胞化学杂志 2004年第3期13卷 367-368页

作者： leizhang TaoYang AiyuanHu ChunfangZhao DepartmentofHistologyandEmbryology HebeiMedicalUniversity050017P.R.China

Immunohistologic study of inhibiting efficacy of EC3 on chronic rejection of rat cardiac allografts

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中国组织化学与细胞化学杂志 2004年第3期13卷 405-406页

作者： leizhang ShinjiMiyamoto TatusoShimada TetsuoHadama DepartmentofHistologyandEmbryology HebeiMedicalUniversityShijiazhuang050017P.R.China Departmentofcirculation OitaMedicalUniversityJapan