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Explicit Solutions for a (2+1)-Dimensional Toda Lattice with Two Discrete Variables

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Communications in Theoretical Physics 2007年第10期48卷 667-670页

作者： WANG Zheng-Yan YANG Xiao department of Mathematics,zhengzhou university,zhengzhou 450052,china department of Mathematics Zhengzhou University Zhengzhou 450052 China

An integrable(2+1)-dimensional Toda lattice with two discrete variables is investigated again,which isproduced from a compatible condition of the Lax *** Darboux transformation for its spectral problems is *** an appl... 详细信息

关键词： Toda lattice two discrete variables Darboux transformation explicit solution

Classification of hypersurfaces with parallel Mobius second fundamental form in S^(n+1)

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Science china Mathematics 2004年第3期47卷 417-430页

作者： HU Zejun LI Haizhong department of Mathematics, zhengzhou university zhengzhou 450052, china department of Mathematical Sciences, Tsinghua university, Beijing 100084, china department of Mathematics Zhengzhou University Zhengzhou China department of Mathematical Sciences Tsinghua University Beijing China

Let Mn(n≥2) be an immersed umbilic-free hypersurface in the(n+1)-dimensional unit sphere Sn+1. Then Mn is associated witha so-called M(o)bius metric g, and a M(o)bius second fundamental form Bwhich are invariants of Mn under the M(o)bius transformation groupof Sn+*** this paper, we classify all umbilic-free hypersurfaces withparallel M(o)bius second fundamental form.

关键词： parallel Mobius second fundamental form,hypersurface, Mobius metric, Mobius equivalence.

Semisymmetric Cubic Graphs as Regular Covers of K3,3

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Acta Mathematica Sinica,English Series 2008年第3期24卷 405-416页

作者： Chang Qun WANG Tie Sheng CHEN department of Mathematics,zhengzhou university,zhengzhou,450052,P.R.china department of Mathematics Zhengzhou University Zhengzhou P. R. China

A regular graph X is called semisymmetric if it is edge-transitive but not *** G≤Aut X,we call a G-cover X semisymmetric if X is semisymmetric,and call a G-cover Xone-regular if Aut X acts regularly on its *** this paper,we give the sufficient and necessaryconditions for the existence of one-regular or semisymmetric Z_n-covers of K3,***,an infinite familyof semisymmetric Z_n×Z_n-covers of K3,3are constructed.

关键词： semisymmetric graph symmetric graph covering graph one-regular graph

Nuclear Factor-κB Signaling Pathway Constitutively Activated in Esophageal Squamous Cell Carcinoma Cell Lines and Inhibition of Growth of Cells by Small Interfering RNA

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Acta Biochimica et Biophysica Sinica 2006年第5期38卷 318-326页

作者： Fang TIAN Wei-Dong ZANG Wei-Hong HOU Hong-Tao LIU Le-Xun XUE Laboratory for Cell Biology,medical college,zhengzhou university,zhengzhou 450052,china Laboratory for Cell Biology Medical College Zhengzhou UniversityZhengzhou 450052 China

Although constitutive nuclear factor(NF)-kB activation has been reported in many humantumors,the role of the NF-kB pathway in esophageal squamous cell carcinoma(ESCC)has not been *** this study,NF-kB pathway in two ESCC cell lines was investigated using immunocytochemistry,Westernblot and reverse transciiption-polymerase chain *** activation of NF-kB DNA binding was determinedby electrophoretic mobility-shift *** interference was used to specifically inhibit the expression *** of cells Was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide *** results showed that p50,p65,IkBα,p-IkBα and IkB kinase β were expressed and mainly localized in *** transcription-polymerase chain reaction results showed the constitutive expressions ofp50,p65 and IkBα mRNA in the two ESCC cell ***,the nuclear extracts revealed that p50and p65 translocated to the nucleus had DNA-binding ***,small interfering RNA of p65 decreasedthe expression of p65,and the viability of ceils transfected with p65 small interfering RNA was significantlysuppressed at the same concentration of 5-fluorouracil(P<0.05)compared to untransfected *** resultsof this study showed that there was the constitutively activated NF-kB signaling pathway in the ESCC *** interference targeting at p65 increased the sensitivity of the ESCC cell lines to 5-fluorouracil,suggesting that NF-kB might be a good target for cancer treatment.

关键词： NF-κB RNA interference esophageal squamous cell carcinoma IκBα IκBα kinase

Phylogeny of Ptychostomum (Bryaceae,Musci) inferred from sequences of nuclear ribosomal DNA internal transcribed spacer (ITS) and chloroplast rps4

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Journal of Systematics and Evolution 2009年第4期47卷 311-320页

作者： ~(1,2)Chen-Ying WANG ~1Jian-Cheng ZHAO~* 1(college of Life Science,Hebei Normal university,Shijiazhuang 050016,china) 2(department of Life Science,zhengzhou Teachers college,zhengzhou 450044,china) (college of Life Science Hebei Normal University Shijiazhuang 050016 China) (department of Life Science Zhengzhou Teachers College Zhengzhou 450044 China)

The phylogeny of Ptychostomum was first undertaken based on analysis of the internal transcribed spacer(ITS)region of the nuclear ribosomal(nr)DNA and by combining data from nrDNA ITS and chloroplast DNA rps4 *** parsimony,maximum likelihood,and Bayesian analyses all support the conclusion that the reinstated genus Ptychostomum is not *** funkii(Schw(a|¨)gr.)*** (≡Bryum funkii Schw(a|¨)gr.)is placed within a clade containing the type species of Bryum,*** Hedw. The remaining members of Ptychostomum investigated in the present study constitute another well-supported clade. The results are congruent with previous molecular *** the basis of phylogenetic evidence,we agree with transferring *** Mü***.(≡***(Brid.)Turton≡Bryum archangelicum Bruch & Schimp.), Bryum lonchocaulon Mü***.,Bryum pallescens *** Schw(a|¨)gr.,and Bryum pallens *** Ptychostomum.

关键词： Bryum molecular phylogeny nuclear ribosomal DNA internal transcribed spacer sequences Ptychostomum rps4 sequences.

Silicon nanoporous pillar array and its surface copper deposition

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Chinese Science Bulletin 2005年第14期50卷 1424-1428页

作者： FU Xiaonan1,2,3, CHAI Huadou1,2 & LI Xinjian1,2 1. department of Physics, zhengzhou university, zhengzhou 450052, china 2. Key Laboratory of Material Physics (zhengzhou university), Ministry of Education, zhengzhou 450052, china 3. department of Mathematics and Physics, Henan university of Tech- nology, zhengzhou 450052, china department of Physics Zhengzhou University Zhengzhou China Key Laboratory of Material Physics (zhengzhou university) Ministry of Education Zhengzhou China department of Mathematics and Physics Henan University of Technology Zhengzhou China

Silicon nanoporous pillar array (Si-NPA) has been prepared by a hydrothermal etching technique. Using Si-NPA as substrate, a Cu/Si-NPA nanocomposite thin film has been obtained with immersion plating method. Morpho- logical and structural analysis indicates that Si-NPA is a typical structural composite system characterized by a triple hierarchical structure, i. e. the array of micron-sized silicon pillars, the nanopores densely distributed on the surface of the pillars, and the silicon nanocrystallites that constitute the pore walls. Cu/Si-NPA inherits the morphological character- istics of Si-NPA. The compactability of the deposited copper nanoparticles varies alternatively with the local geometrical features of Si-NPA and forms a quasi-periodical pattern. Such an experimental phenomenon is attributed to the veloc- ity dependence of the copper deposition upon the local geo- metrical features of Si-NPA. These results indicate that Si-NPA might be used as an ideal template for preparing specially patterned, structured or functionalized metal/ sili- con nanocomposite systems.

关键词：硅元素薄膜蚀刻技术电镀技术

SYNTHESIS AND CHARACTERIZATION OF ORGANOMONTMORILLONITE AND POLYAMIDE 66/MONTMORILLONITE NANOCOMPOSITES

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Chinese Journal of Polymer Science 2002年第6期20卷 551-557页

作者： Cheng-shen Zhu Xin Kang Su-qin He Liu-yang Wang Li-yun Lu college of Materials Engineering,zhengzhou university, zhengzhou 450052, china college of Materials Engineering Zhengzhou University Zhengzhou 450052

The montmorillonites (MMTs), layered, smectite-type silicates, were premodified by two different methods prior to the polymer melt intercalation. In one case MMTs were modified with cetyltrimethylammonium bromide (CTAB), and termed as organomontmorillonites (OMMTs); in the other case MMTs were modified by nylon, and the products were called modified montmorillonites (MMMTs). The effects of CTAB and nylon on the MMTs were investigated by using TG and WAXD. The results show that interlayer spacings of CTAB and nylon modified MMTs are larger than that of sodium MMTs. Then, polyamide 66 (PA 66)/MMT nanocomposites were obtained through the method of melt intercalation of polymers. The nanocomposites were characterized by WAXD, TEM and Molau experiments. The results indicate that the MMTs disperse homogeneously in the PA 66 matrix. The mechanical properties of nanocomposites, such as tensile properties and flexural properties, were also measured and show a tendency to increase with increase of MMT content and reach the maximum values at 5phr MMT content. The heat distortion temperature (HDT) of the nanocomposites (7 phr) is about 32 K higher than that of pure PA 66.

关键词： montmorillonite polyamide 66 nanocomposites melt intercalation

Structure and magnetism of a porous three-dimensional metal-organic framework based on planar tetranuclear copper(Ⅱ) cluster units

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Science china Chemistry 2010年第10期53卷 2118-2122页

作者： LI HuiJun, ZHANG ErPeng, GUO QianQian, HOU HongWei & FAN YaoTing department of Chemistry, zhengzhou university, zhengzhou 450052, china department of Chemistry Zhengzhou University Zhengzhou China

A porous three-dimensional copper(Ⅱ) metal-organic framework (MOF) {[Cu2(tci)(OH)(pip)0.5(H2O)]·6H2O}n (1) [tci = tris (2-carboxyethyl)isocyanurate, pip = piperazine] has been generated under hydrothermal conditions at 120 °C. Single crystal X-ray diffraction reveals that the polymer exhibits a novel three-dimensional framework based on planar tetranuclear copper(Ⅱ) cluster units. The variable temperature magnetic susceptibility data in the range 2-280 K show antiferromagnetic spin-spin coupling in the tetranuclear unit in complex 1. A theoretical fitting of the magnetic data gives J values of -31.3 cm-1, -30.8 cm-1, and 13.5 cm-1.

关键词： metal–organic framework tetranuclear copper cluster unit topology magnetism

THE NP-HARDNESS OF THE SINGLE MACHINE COMMON DUE DATE WEIGHTED TARDINESS PROBLEM

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Systems Science and Mathematical Sciences 1992年第4期5卷 328-333页

作者： YUAN Jinjiang (department of Mathematics,zhengzhou university,zhengzhou 450052,china)

In this paper we prove that the single machine common due dateweighted tardiness problem is NP-hard.

关键词： Due date tardiness NP-complete