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Asymptotic Approximations of Jacobi Functions and Their Zeros with Error Bounds

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Acta Mathematica Sinica,English Series 2006年第3期22卷 729-740页

作者： Xiao feng ZHU xiu Chun LI Department of Basic Science Beijing Institute of Graphic Communication

The study of zeros of orthogonal functions is an important topic. In this paper, by improving the middle variable x（t）, we＇ve got a new form of asymptotic approximation, completed with error bounds, it is constructed for the Jacobi functions φu^（α,β）（t）（α 〉 -1） as μ→∞. Besides, an accurate approximation with error bounds is also constructed correspondingly for the zeros tμ,s of φu^（α,β）（t）（α≥ 0） as μ→∞, uniformly with respect to s = 1, 2,....

关键词： Asymptotic approximation Jacobi function Zero Error bounds

Grading Method for Hypoxic-Ischemic Encephalopathy Based on Neonatal EEG

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Computer Modeling in Engineering & Sciences 2020年第2期122卷 721-741页

作者： Jingmin Guo xiu cheng Duanpo Wu Fujian Provincial Maternity and Children’s Hospital Affiliated Hospital of Fujian Medical UniversityFuzhouChina. School of Communication Engineering Hangzhou Dianzi UniversityHangzhouChina. Hangzhou Neuro Science and Technology Co. Ltd.HangzhouChina.

The grading of hypoxic-ischemic encephalopathy(HIE)contributes to the clinical decision making for neonates with *** this paper,an automated grading method based on electroencephalogram(EEG)data is proposed to describe the severity of HIE infants,namely mild asphyxia,moderate asphyxia and severe *** automated grading method is based on a multi-class support vector machine(SVM)classifier,and the input features of SVM classifier include long-term features which are extracted by decomposing the EEG data into different 64 s epoch data and short-term features which are extracted by segmenting the 64 s epoch data into 8 s epoch data with 4 s *** note,the correlation coefficient and asymmetry extracted in this paper have obvious discriminating capability in HIE infants *** experimental results show that the proposed method can achieve the classification accuracy of 78.3%,75.8%and 87.0%of the mild asphyxia group,moderate asphyxia group and severe asphyxia group,***,the overall accuracy and kappa used to evaluate the performance of the proposed method can reach 79.5%and 0.69,respectively.

关键词： Hypoxic-ischemic encephalopathy electroencephalograph neonate support vector machine.

Design,synthesis and biological evaluation of amino organophosphorus imidazoles as a new type of potential antimicrobial agents

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Science China Chemistry 2017年第6期60卷 769-785页

作者： Wei-Wei Gao Syed Rasheed VijaiKumarReddy Tangadanchu Yi Sun Xin-Mei Peng Yu cheng feng-xiu Zhang Jian-Mei Lin cheng-He Zhou Institute of Bioorganic&Medicinal Chemistry Key Laboratory of Applied Chemistry of Chongqing MunicipalitySchool of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China School of Medicine University of Electronic Science and Technology of China Chengdu 610072China

A series of amino organophosphorus imidazoles were designed and synthesized as a novel structural type of antimicrobial *** evaluation in vitro showed that compound 3f exhibited equipotent or superior anti-methicillin-resistant Staphylococcus aureus(anti-MRSA) and anti-S. cerevisiae efficiencies(minimal inhibitory concentration(MIC)=2 μg/mL) to clinical drugs,and the combinations with antibacterial or antifungal drugs enhanced the antimicrobial efficiency. Highly active molecule 3f showed low propensity for bacteria to develop resistance, and the preliminary action mechanism studies demonstrated that 3f was membrane-active, but had no significant intercalation towards MRSA DNA. The computational study on 3f reasonably explained its high antimicrobial activity. Experimental data revealed that ground-state 3f-HSA complexes were formed mainly through hydrophobic interactions and hydrogen bonds with a spontaneous process, and the non-radioactive energy transfer from HSA to 3f occurred beyond F鰎ster resonance energy transfer theory. The participation of metal ions in 3f-HSA supramolucular system could increase the concentration of free compound 3f, and shorten its storage time and half-life in the blood to improve the maximum antimicrobial efficacy.

关键词： organophosphorus imidazole antibacterial antifungal HSA

Whittaker Modules for the Derivation Lie Algebra of Torus with Two Variables

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Acta Mathematica Sinica,English Series 2016年第10期32卷 1177-1188页

作者： Hai feng LIAN xiu Fu ZHANG Department of Mathematics Fujian Agriculture and Forestry UniversityFuzhou 350002P.R.China School of Mathematics and Statistics Jiangsu Normal UniversityXuzhou 221116P.R.China

Let L be the derivation Lie algebra of C[t1^±1 , t2^±1 ]. Given a triangle decomposition L = L＋ η ＋ L-, we define a nonsingular Lie algebra homomorphism φ ： L＋ → C and the universal Whittaker L-module We of type φ. We obtain all Whittaker vectors and submodules of We. Moreover, all simple Whittaker L-modules of type φ are determined.

关键词： Whittaker vector Whittaker module simple module derivation Lie algebra

Hydrothermal Synthesis and Crystal Structure of a Novel Isophthalate-bridged Copper(II) Polymer with Two-dimensional Network Structure: [Cu_2(phen)(ipt)_2]_(2n)·nH_2O (ipt = isophthalate, phen = 1,10-phenanthroline)

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Chinese Journal of Structural Chemistry 2005年第12期24卷 1411-1415页

作者： CUI Yun-cheng LI xiu-Mei LI Chuan-Bi WANG Qing-Wei LIU Bo LI Guo-feng Jilin Normal University Siping Jilin 136000 China Department of Chemistry Tonghua Teachers college Tonghua Jilin 134002 China

A novel metal-organic coordination polymer [Cu2（phen）（ipt）2]2n-nH2O 1 has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group P21/c with a = 12.338（3）, b = 12.167（3）, c = 18.167（4）A, β= 111.686（14）°, V = 2534.1（10）A^3, C28H18Cu2N2O9, Mr = 653.52, Dc = 1.713 g/cm^3,μ（MoKα） = 1.740 mm^-1, F（000） = 1320, Z = 4, the final R = 0.0443 and wR = 0.0853 for 3543 observed reflections （1 〉 2σ（I））. It exhibits a novel two-dimensional network with tetra-Cu-ipt-as building units.

关键词： isophthalate coordination polymer hydrothermal synthesis crystal structure

Leakage Prediction Method for Contacting Mechanical Seals with Parallel Faces

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Chinese Journal of Mechanical Engineering 2010年第1期23卷 7-15页

作者： SUN Jianjun WEI Long feng xiu GU Boqin College of Mechanical and Electronic Engineering Nanjing Forestry UniversitY Nanjing 21003 7 China Department of Engineering Mechanics Southeast University Nanjing 210096 China Fluid Sealing Technique Development Center Nanjing College of Chemical Technology Nanjing 210048 China College of Mechanical and Power Engineering Nanjing University of Technology Nanjing 210009 China

Since the beginning of the 20th century, many researches on the sealing characteristic of mechanical seals were carried out broadly and in depth by various methods and some leakage models were built. But due to the lack of the way to characterize the main factors of influence on the leakage, most of the early researches were based on the assumptions that the seal faces topography and the frictional conditions were invariant. In the early built models, the effect of the surface topography change of the seal face on the leakage rate was neglected. Based on the fractal theory, the contact of end faces of the rotary and stationary rings was simplified to be the contact of a rough surface and an ideal rigid smooth surface, and the contact interface＇s cavity size-distribution function as well as the fractal characteristic of the cavity profile curve was discussed. By analyzing the influence of abrasion on the seal face topography and the leakage channel, the time-correlation leakage prediction model of mechanical seals based on the fractal theory was established and the method for predicting the leakage rate of mechanical seals with parallel plane was proposed. The values of the leakage rate predicted theoretically are similar to the measured values of the leakage rate in the model test and in situ test. The experimental results indicate that the leakage rate of mechanical seals is a transient value. The surface topography of the end faces of the seal tings and its change during the frictional wear of mechanical seals can be accurately characterized by the fractal parameters. Under the work conditions of changeless frictional mechanism, the fractal parameters measured or calculated based on the accelerated testing equation can be used to predict the leakage rate of mechanical seal in service. The proposed research provides the basis for determining the leakage state and predicting working life of mechanical seal.

关键词： mechanical seal leakage rate fractal theory frictional wear accelerated test model

Effects of Exogenous Silicon on Photosynthetic Capacity and Antioxidant Enzyme Activities in Chloroplast of Cucumber Seedlings Under Excess Manganese

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Agricultural Sciences in China 2009年第1期8卷 40-50页

作者： feng Jian-peng SHI Qing-hua WANG xiu-feng College of Horticultural Science and Engineering Shandong Agricultural University Tai＇an 271018 P.R.China State Key Laboratory of Crop Biology Tai＇an 271018 P.R.China

Effects of silicon on photosynthetic parameters and antioxidant enzymes of chloroplast in cucumber seedlings under excess Mn were studied. Compared with the control, excess Mn significantly inhibited net photosynthetic rate （Pn）, stomatal conductance, as well as the maximum yield of the photosystem II photochemical reactions （Fv/Fm） and the quantum yield of photosysytem II electron transport （Φ PSII）, application of Si reversed the negative effects of excess Mn. In the further investigation, it was obtained that application of Si significantly increased the activities of enzymes related with ascorbate-glutathione cycle including ascorbate peroxidase （APX）, dehydroascorbate reductase （DHAR） and glutathione reductase （GR） in cucumber chloroplast under excess Mn, this could be responsible for the lower accumulation of H2O2 and lower lipid peroxidation of chloroplast induced by Mn, and resulted in keeping higher photosynthesis.

关键词： cucumber excess manganese photosynthesis chlorophyll fluorescence chloroplast antioxidant enzymes

Two new tetrahydronaphthalenes from the stem of Impatiens balsamina L.

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Chinese Chemical Letters 2010年第4期21卷 440-442页

作者： Chen, xiu Mei Qian, Shi Hui feng, feng Jiangsu Prov Acad Tradit Chinese Med Nanjing 210028 Peoples R China China Pharmaceut Univ Dept Phytochem Nanjing 210009 Peoples R China

Two new tetrahydronaphthalenes,lα,2α-diol-4α-ethoxy-1,2,3,4-tetrahydronaphthalene(1) and 1a,2a,4β-triol-1,2,3,4- tetrahydronaphthalene(2),were isolated from the stem of Impatiens balsamina *** structures were eluc... 详细信息

关键词： Impatiens balsamina L. Balsaminaceae Tetrahydronaphthalene

Synthesis, DNA-binding, and Photocleavage of 2,3-Di-2-pyridylquinoxaline-silver(Ⅰ) Complex

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Chemical Research in Chinese Universities 2008年第1期24卷 15-19页

作者： WANG xiu-li FANG Jia-ni BI Yan-feng LIN Hong-yan LIU Guo-cheng Faculty of Chemistry and Chemical Engineering Liaoning Key Laboratry of Applied Chemistry Bohai University Jinzhou 121000 P. R. China

A new dinuclear complex, [Ag（L）（CH3CN）]2（ClO4）2·2H2O（L=2,3-di-2-pyridylquinoxaline）, was prepared and characterized by elemental analyses, IR spectroscopy, and single-crystal X-ray diffraction analyses. The interaction of the complex with calf thymus DNA（CT-DNA） was investigated by absorption, fluorescence spectroscopies, and viscosity measurement. The results suggested that the complex was bound to DNA via an intercalative mode. The intrinsic binding constant value Kb was found to be approximately 1.48×10^3 L·mol^-1. Moreover, the Ag（I） complex could cleave the plasmid pUC19 DNA from the supercoiled Form Ⅰto the nicked FormⅡ under irradiation at 365 nm.

关键词： DNA Ag-Polypyridyl complex Interaction Fluorescence Cleavage