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The best quadrature formula based on Hermite information for the class KW^(2)[a,b]

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Science China Mathematics 2005年第1期48卷 79-87页

作者： wang xinghua MI Xiangjiang Department of Mathematics Zhejiang UniversityHangzhou 310028China College of Mathematics and Infomation Science Wenzhou UniversityWenzhou 325003China Department of MathematicsZhejiang UniversityHangzhou 310028China

The best quadrature formula has been found in the following sense: for a function whose norm of the second derivative is bounded by a given constant and the best quadrature formula for the approximate evaluation of integration of that function can minimize the worst possible error if the values of the function and its derivative at certain nodes are *** best interpolation formula used to get the quadrature formula above is also ***,we compare the best quadrature formula with the open compound corrected trapezoidal formula by theoretical analysis and stochastic experiments.

关键词： class of second differentiable functions,Hermite information,best quadrature formula,best interpolation method,stochastic experiment,open compound corrected trapezoidal formula,Iyengar-type inequalities.

ON THE DIVIDED DIFFERENCE FORM OF FAA DI BRUNO＇S FORMULA Ⅱ

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Journal of Computational Mathematics 2007年第6期25卷 697-704页

作者： xinghua wang Aimin Xu Department of Mathematics Zhejiang University Hangzhou 310027 China

In this paper, we consider the higher divided difference of a composite function f（g（t）） in which g（t） is an s-dimensional vector. By exploiting some properties from mixed partial divided differences and multivariate Newton interpolation, we generalize the divided difference form of Faà di Bruno＇s formula with a scalar argument. Moreover, a generalized Faà di Bruno＇s formula with a vector argument is derived.

关键词： Bell polynomial Faà di Bruno's formula Mixed partial divided difference,Multivariate Newton interpolation.

Numerical simulation of A1203 deposition at a nozzle during continuous casting

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Journal of University of Science and Technology Beijing 2008年第3期15卷 227-235页

作者： Fangming Yuan xinghua wang Jiongming Zhang Li Zhang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China Metallurgical Equipment Company of China （MECC） Sinosteel Corporation Beijing 100080 China Baosteel Advanced Technology Institute Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China

The effects of various factors, such as argon flow rate and slide gate opening ratio, on the alumina deposition rate were researched by the numerical simulation method. The pressure in the nozzle is significantly affected by argon flow rate and slide gate opening ratio. To keep positive pressure in the nozzle, the argon flow rate should be increased with a decrease in slide gate opening ratio. The effect of argon flow rate on the alumina deposition rate depends on the condition of opening ratio or casting speed. The effect of increasing the argon flow rate on the deposition rate is not obvious when the opening ratio is small. The A1203 deposition rate decreases significantly with an increase in argon flow rate when the argon flow rate is low, but it decreases slowly when the argon flow rate reaches a certain value. The alumina deposition rate is linear with alumina content at different slide gate opening ratios and argon flow rates. The observed thickness of the deposition layer at the bottom and outlet of a real clogged nozzle is almost equal to the result of the numerical simulation.

关键词： continuous casting nozzle clogging numerical simulation

Online forecasting model of tundish nozzle clogging

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Journal of University of Science and Technology Beijing 2006年第1期13卷 21-24页

作者： Fangming Yuan xinghua wang Jiongming Zhang Li Zhang Metallurgical and Ecological Engineering School University of Science and Technology Beijing Beijing 100083 China Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China

A nozzle clogging online forecasting model based on hydrodynamics engineering was developed, in which the actual flow rate was calculated from the mold width, thickness, and casting speed. There is a linear relationship between the theoretical flow rate and the slide gate opening ratio as the molten steel level, argon flow rate, and the top slag weight are kept constant, and the relationship can be obtained by regression of the data collected at the beginning of the first heat in each casting sequence when the nozzle clogging does not occur. Then, during the casting, the theoretical flow rate can be calculated at intervals of one second. Comparing the theoretical flow rate with the actual flow rate, the online nozzle clogging ratio can be obtained at intervals of one second. The computer model based on the conception of the nozzle clogging ratio can display the degree of the nozzle clogging intuitively.

关键词： continuous casting tundish nozzle clogging online forecasting model

Comprehensive genomic analysis and expression profiling of cysteine-rich polycomb-like transcription factor gene family in tea tree

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Horticultural Plant Journal 2021年第5期7卷 469-478页

作者： Hong Nan Yanglei Lin xinghua wang Lizhi Gao Plant Germplasm and Genomics Center Germplasm Bank of Wild Species in Southwest ChinaKunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of the Chinese Academy of Sciences Beijing 100039China Yunnan Pu’er Tea Tree Breeding Station Pu Er 665099China Institution of Genomics and Bioinformatics South China Agricultural UniversityGuangzhou 510642China

Cysteine-rich polycomb-like(CPP)is a small gene family in plants,which plays key role in plant development and stress *** CPP transcription factors have been characterized in several other plant species,a genome-wide characterization of the CPP gene family has been absent in Camellia *** this study,we totally identified 7,8,and 8 non-redundant CsCPP genes in three published genomes,including Camellia sinensis *** ***-10(CSA-YK10),Camellia sinensis *** ***(CSS-BY)and Camellia sinensis *** ***(CSS-SCZ).CPP proteins from tea tree and other plant species were classified into three groups,which were further divided into four subgroups based on phylogenetic *** CPP genes in the same subgroup had similar gene structures and conserved *** cis-acting elements analysis indicated that CPP genes might be involved in plant growth,development and stress *** of gene expression using qRT-PCR experiments validated that CPP genes exhibited different expression patterns across the examined *** the genes were expressed differentially in a range of tissues,indicating that CPPs were involved in a range of developmental and physiological *** study has obtained new insights into the evolution and function of the CPP gene family in the growth and development of tea plants,and also provide candidate genes for further functional characterization in tea tree.

关键词： Camellia sinensis CPP transcription factor Genome-wide analysis Gene expression profiling

Efficient Chebyshev Spectral Method for Solving Linear Elliptic PDEs Using Quasi-Inverse Technique

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Numerical Mathematics(Theory,Methods and Applications) 2011年第2期4卷 197-215页

作者： Fei Liu Xingde Ye xinghua wang Department of Mathematics Zhejiang UniversityHangzhouZhejiang 310027China

We present a systematic and efficient Chebyshev spectral method using quasiinverse technique to directly solve the second order equation with the homogeneous Robin boundary conditions and the fourth order equation with the first and second boundary *** key to the efficiency of the method is to multiply quasiinverse matrix on both sides of discrete systems,which leads to band structure *** can obtain high order accuracy with less computational *** multi-dimensional and more complicated linear elliptic PDEs,the advantage of this methodology is *** results indicate that the spectral accuracy is achieved and the proposed method is very efficient for 2-D high order problems.

关键词： Chebyshev spectral method quasi-inverse Helmholtz equation Robin boundary conditions general biharmonic equation

Carbene-enabled ether activation through the formation of oxonium: a theoretical view

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Organic Chemistry Frontiers 2022年第5期9卷 1247-1253页

作者： Ya-Nan wang xinghua wang Shi-Jun Li Yu Lan College of Chemistry and Institute of Green CatalysisZhengzhou University100 Science AvenueZhengzhou 450001HenanP.R.China School of Chemistry and Chemical Engineering and Chongqing Key Laboratory of Theoretical and Computational ChemistryChongqing UniversityChongqing 400030P.R.China

Here,we report a theoretical investigation of the reactivity and chemoselectivity of carbene-enabled ether *** mechanism obtained from DFT calculations revealed that the final products were dependent on the stability of the oxonium intermediate,which was afforded by nucleophilic attack of the corresponding ether onto a carbene ***,we found that the nucleophilicity of ethers was crucial but not their *** decomposition analysis based on absolutely localized molecular orbitals showed that the nucleophilicity of ethers was critical for polarization and charge transfer,leading to the chemoselectivity.

关键词： activation absolutely carbene

Optimal Design and Dynamic Simulation of Mountain Bike with Rear Suspension

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Chinese Journal of Mechanical Engineering 2009年第1期22卷 21-26页

作者： BU Yan XIANG Zhongxia HUANG Tian ZHANG Xu wang xinghua School of Mechanical Engineering Tianjin University Tianjin 300072 China Tianjin Entry-exit Inspection and Quarantine Bureau Tianjin 300211 China

This paper investigates the dynamic design methodology of mountain bikes with rear suspension. Firstly, a multi-rigid body dynamic model of rider and mountain bike coupled system is constructed. The rider model includes 19 skeletons, 18 joints and 118 main muscles. Secondly, to validate the feasibility of the model, an experiment test is designed to reflect the real cycling status. Finally, aiming at enhancing the performance of the rider vibration comfort, the scale parameters of rear suspension are optimized with computer simulation and uniform design. The mathematical model in the vibration performance and the design variables is constructed with regression analysis. The result shows that when the length of side link is 90 mm, the length of connected rod is 336.115 1 mm and the included angle between absorber and side link is 60°, the mountain bike has better vibration comfort. This study and relevant conclusions are of practical importance to the design of the mountain bike＇s rear suspension system.

关键词： mountain bike model building dynamic simulation experiment test vibrant comfort optimal design

Wavelength-selectivity polarization dependence of optical absorption and photoresponse in SnS nanosheets

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Nano Research 2021年第7期14卷 2224-2230页

作者： Yu Cui Ziqi Zhou xinghua wang Xiaoting wang Zhihui Ren Longfei Pan Juehan Yang State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of Sciences&Center of Materials Science and Optoelectronics EngineeringUniversity of Chinese Academy of SciencesBeijing 100083China Department of Ophthalmology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

The optical and optoelectronic characteristics of SnS nanosheets with strong anisotropic crystal structure are *** electron microscopy and polarized Raman spectra are used to determine the crystal orientation of SnS *** photodetector based on SnS nanosheets exhibits the carrier mobility of 37.75 cm^(2)/V·s,photoresponsivity of 310.5 A/W and external quantum efficiency of 8.56×10^(4)%at 450 *** absorption around the absorption edge presents obvious polarization sensitivity with the highest optical absorption dichroic ratio of 3.06 at 862 *** to anisotropic optical absorption,the polarized photocurrent appears as the periodic change affected by the polarized direction of the incident light at 808 ***,SnS nanosheets show good potential in the future application of the polarized photodetectors for specific wavelength.

关键词： SnS anisotropy optical characteristic polarized photoresponse