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Chinese Journal of Polymer Science 2010年第6期28卷 903-911页

作者： Nan-xi Chen jun-hua zhang State Key Laboratory of Polymer Materials Engineering of China Sichuan UniversityChengdu 610065China

The aim of this work is to investigate the hydrogen-bonding interaction in poly(vinyl alcohol)(PVA)/poly(acrylic acid)(PAA) blending system and its influence on rheological properties in solution and the physical properties in solid state. Introducing PAA into PVA solutions resulted in a thickening behavior of blend *** viscosity of the solutions increased with PAA content increasing,and a maximum viscosity could be obtained when the ratio of PVA/PAA was 70/30. The intermolecular hydrogen-bonding and miscibility between PVA and PAA in solid state were investigated by differential scanning calorimetry(DSC),Fourier transform infrared spectroscopy(FTIR) and mechanical *** results displayed the great influence of introducing PAA on the properties of blending *** tensile strength increased from 89.31 MPa to 119.8 MPa and Young’s modulus improved by over 300%with increasing PAA concentration compared with those of pure PVA *** systematically studying the rheological behaviors of solutions and the physical properties of films,the influence of hydrogen-bonding in solutions and solid states were discussed.

关键词： Polymer blending Rheology Hydrogen-bonding Molecular network Miscibility

Structure of Independent Sets in Direct Products of Some Vertex-transitive Graphs

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Acta Mathematica Sinica,English Series 2012年第4期28卷 697-706页

作者： Xing Bo GENG jun WANG hua jun zhang School of Mathematical Science Dalian University of Technology Department of Mathematics Shanghai Normal University Department of Mathematics Zhejiang Normal University

Let Circ（r, n） be a circular graph. It is well known that its independence number α（Circ（r, n）） = r. In this paper we prove that for every vertex transitive graph H, and describe the structure of maximum independent sets in Circ（r, n） × H. As consequences, we prove for G being Kneser graphs, and the graphs defined by permutations and partial permutations, respectively. The structure of maximum independent sets in these direct products is also described.

关键词： Vertex-transitivity primitivity independence number

Erds-Ko-Rado Theorem for Ladder Graphs

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Acta Mathematicae Applicatae Sinica 2014年第3期30卷 583-588页

作者： Yu-shuang LI hua-jun zhang School of Science Yanshan University Department of Mathematics Zhejiang Normal University

For a graph G and an integer r ≥ 1, G is r-EKR if no intersecting family of independent r-sets of G is larger than the largest star （a family of independent r-sets containing some fixed vertex in G）, and G is strictly r-EKR if every extremal intersecting family of independent r-sets is a star. Recently, Hurlbert and Kamat gave a preliminary result about EKR property of ladder graphs. They showed that a ladder graph with n rungs is 3-EKR for all n ≥3. The present paper proves that this graph is r-EKR for all 1 ≤ r 〈 n, and strictly r-EKR except for r = n - 1.

关键词： ErdSs-Ko-Rado (EKR) theorem intersecting family ladder graph

Efficient Statistical Inference for Partially Nonlinear Errors-in-Variables Models

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Acta Mathematica Sinica,English Series 2014年第9期30卷 1606-1620页

作者： San Ying FENG Gao Rong LI jun hua zhang College of Applied Sciences Beijing University of Technology College of Mechanical Engineering Beijing Information Science and Technology University

In this paper, we consider the partially nonlinear errors-in-variables models when the non- parametric component is measured with additive error. The profile nonlinear least squares estimator of unknown parameter and the estimator of nonparametric component are constructed, and their asymptotic properties are derived under general assumptions. Finite sample performances of the proposed statistical inference procedures are illustrated by Monte Carlo simulation studies.

关键词： Partially nonlinear errors-in-variables model measurement error ordinary smooth profile nonlinear least squares asymptotic property

Broadband channel measurement and analysis

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The Journal of China Universities of Posts and Telecommunications 2006年第3期13卷 24-28页

作者： zhang Ming zhang Jian-hua JIANG jun zhang Ping WU Yu-fei Wireless Technology Innovation Labs (WTI) Beijing University of Posts and Telecommunications Beijing 100876 China

An outdoor propagation measurement campaign for beyond 3G （B3G） as well as a wide-band indoor measurement campaign have been performed recently in Beijing, China, in which the sounding signals are transmitted by an one-antenna base station and received by a two-antenna mobile receiver operated at 3.49～3.51 GHz bandwidth. Different scenarios： stationary line-of-sight （LoS）, stationary non-LoS （NLoS） scenarios, and dynamic NLoS are deliberately chosen in a classic urban environment and office environment. The initial results are presented in this article. Parameters including vector channel impulse response, path loss, rays number, excess delay spread etc. are extracted, analyzed, and briefly reported here.

关键词： Broadband measurement Beyond 3G path loss,multipath delay rays number

High performance liquid chromatography with immobilized Ru(bpy)_3^(2+)-KMnO_4 chemiluminescence detection and its application in metabolism of repaglinide in pig liver microsomes

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Chinese Chemical Letters 2011年第10期22卷 1245-1248页

作者： Ai hua Fu Zhu jun zhang Li Li Chen Xiao Ming zhang Pan Xue Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province School of Chemistry and Materials Science Shaanxi Normal University Xi＇ an 710062 China

A novel high performance liquid chromatography-chemiluminescence（HPLC-CL） method for investigation of in vitro metabolism of repaglinide in pig liver microsomes with microdialysis sampling technique was *** chromatographic separation was performed on a Hypersil BDS-C18 column with an isocratic mobile phase consisting of methanol and 0.01 mol/L KH_2PO_4（pH 3.0）（volume ratio 75：25） at a flow rate of 1.0 mL/*** detection was based on the chemiluminescence reaction of repaglinide with acidic potassium permanganate（KMnO_4） and tris（2,2＇-bipyridyl）ruthenium（Ⅲ）（Ru（bpy）_3^（3＋））,which was immobilized on the cationic ion-exchange resin for obtaining high sensitivity and reducing consumption of expensive reagent.

关键词： High performance liquid chromatography Chemiluminescence Microdialysis Repaglinide Immobilized Ru(bpy)_3^(2+)

FLUID FLOW IN ROTATING HELICAL SQUARE DUCTS

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Journal of Hydrodynamics 2003年第3期15卷 49-56页

作者： Chen hua-jun, zhang Ben-zhao, zhang Jin-suo Department of Mechanics, Zhejiang University, Hangzhou 310027, China, Dept. of Mech. Zhejiang Univ. Hangzhou 310027 China

A numerical study is made for a fully developed laminar flow in rotatinghelical pipes. Due to the rotation, the Coriolis force can also contribute to the secondary *** interaction between rotation, torsion, and curvature complicates the flow characteristics. Theeffects of rotation and torsion on the flow transitions are studied in details. The results showthat there are obvious differences between the flow in rotating ducts and in helical ducts withoutrotation. Certain hitherto unknown flow patterns are found. The effects of rotation and torsion onthe friction factor are also examined. Present results show the characteristics of the fluid flow inrotating helical square ducts.

关键词： secondary flow rotating ducts helical ducts

Indirect Enzyme-Linked Immunosorbent Assay Based on the Nucleocapsid Protein of SARS-like Coronaviruses

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Virologica Sinica 2009年第2期24卷 146-151页

作者： jun-fa YUAN Yan LI hua-jun zhang Peng ZHOU Zhen-hua KE Yun-zhi zhang Zheng-li SHI Wuhan Institute of Virology Chinese Academy of Sciences Wuhan 430071 China Yunnan Institute ofEndemic Diseases Control and Prevention Dali 671000 China

The nucleocapsid protein(N) is a major structural protein of coronaviruses. The N protein of bat SARS-like coronavirus(SL-CoV) has a high similarity with that of SARS-CoV. In this study,the SL-CoV N protein was expressed in Escherichia coli,purified and used as antigen. An Indirect Enzyme-Linked Immunosorbent Assay(indirect ELISA) was developed for detection of SARS-or SL-CoV infections in bat populations. The detection of 573 bat sera with this indirect ELISA demonstrated that SL-CoVs consistently circulate in Rhinilophus species,further supporting the proposal that bats are natural reservoirs of SL-CoVs. This method uses 1-2 μl of serum sample and can be used for preliminary screening of infections by SARS-or SL-CoV with a small amount of serum sample.

关键词： SARS-like CoV Nucleocapsid protein Indirect ELISA

Identification and Characterization of Nuclear Localization Signals within the Nucleocapsid Protein VP15 of White Spot Syndrome Virus

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Virologica Sinica 2009年第1期24卷 71-76页

作者： Li-juan LI hua-jun zhang Cong zhang Zheng-li SHI State Key Laboratory of Virology Wuhan Institute of Virology Chinese Academy of Sciences Wuhan 430071 China College of Fishery Huazhong Agricultural University Wuhan 430070 China

The nucleocapsid protein VP15 of white spot syndrome virus (WSSV) is a basic DNA-binding protein. Three canonical bipartite nuclear localization signals (NLSs), called NLS1 (aa 11-27), NLS2 (aa 33-49) and NLS3 (44-60), have been detected in this protein, using the ScanProsite computer program. To determine the nuclear localization sequence of VP15, the full-length open reading frame, or the sequence of one of the three NLSs, was fused to the green fluorescent protein (GFP) gene, and transiently expressed in insect Sf9 cells. Transfection with full-length VP15 resulted in GFP fluorescence being distributed exclusively in the nucleus. NLS1 alone could also direct GFP to the nucleus, but less efficiently. Neither of the other two NLSs (NLS2 and 3) was functional when expressed alone, but exhibited similar activity to NLS1 when they were expressed as a fusion peptide. Furthermore, a mutated VP15, in which the two basic amino acids (11RR12) of NLS1 were changed to two alanines (11AA12), caused GFP to be localized only in the cytoplasm of Sf9 cells. These results demonstrated that VP15, as a nuclear localization protein, needs cooperation between its three NLSs, and that the two residues (11RR12) of NLS1 play a key role in transporting the protein to the nucleus.

关键词： White spot syndrome virus (WSSV) Nucleocapsid protein, VP15 Nuclear localization signal (NLS)

Expression and Assembly Mechanism of the Capsid Proteins of a Satellite Virus (XSV) Associated with Macrobrachium rosenbergii Nodavirus

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Virologica Sinica 2008年第1期23卷 73-77页

作者： Jian-min WANG hua-jun zhang Zheng-li SHI State Key Laboratory of Virology Wuhan Institute of Virology Chinese Academy of Sciences （CAS） WuhanHubei 430071 China Graduate School of CAS Beijing 100039 China

The extra small virus （XSV） is a satellite virus associated with Macrobrachium rosenbergii nodavirus （MrNV） and its genome consists of two overlapping ORFs, CP17 and CP16. Here we demonstrate that CP16 is expressed from the second AUG of the CP17 gene and is not a proteinase cleavage result of CP17. We further expressed CP17 and several truncated CP17s （in which the N-or C-terminus or both was deleted）, respectively, in Escherichia coli. Except for the recombinant plasmid CP17^AC10, all recombinant plasmids expressed soluble protein which assembled into virus-like particles （VLPs）, suggesting that the C-terminus is important for VLP formation.

关键词： Extra small virus (XSV) Satellite virus Virus-like particle White tail disease