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Preparation and photocatalytic activity of TiO_2 nanoparticles co-doped with Fe and La

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Particuology 2011年第3期9卷 260-264页

作者： Zhongliang Shi Xiaoxia zhang shuhua Yao School of Applied Chemistry Shenyang University of Chemical Technology Shenyang 110142 China

The catalysts of un-doped, single-doped and co-doped titanium dioxide （TiO2） nanoparticles were prepared by a sol-gel method with Ti（OC4H9 ）4 as a Ti source material. The photo-absorbance of the obtained nanoparticles was measured by UV-vis diffusive reflectance spectroscopy （UV-vis DRS）, and the photocatalytic activity of the prepared samples under UV and visible light was estimated by measuring the degradation rate of phenol （50 mg/L） in an aqueous solution. The effect of Fe and La co-dopants on the material properties was investigated by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and N2 adsorption-desorption isotherm measurement. It was shown that the co-doped TiO2 could be activated by visible light and could thus be used as an effective catalyst in photo-oxidation reactions. The photocatalytic activity of TiO2 co-doped with Fe and La is markedly improved due to the synergistic actions of the two dopants.

关键词： Titanium dioxide Photocatalysis Co-doping Phenol

RICHARDSON EXTRAPOLATION AND DEFECT CORRECTION OF FINITE ELEMENT METHODS FOR OPTIMAL CONTROL PROBLEMS

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Journal of Computational Mathematics 2010年第1期28卷 55-71页

作者： Tang Liu Ningning Yan shuhua zhang Research Center for Mathematics and Economics Tianjin University of Finance and Economics Tianjin 300222 China Institute of System Sciences Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100190 China

Asymptotic error expansions in H^1-norm for the bilinear finite element approximation to a class of optimal control problems are derived for rectangular meshes. With the rectan- gular meshes, the Richardson extrapolation of two different schemes and an interpolation defect correction can be applied. The higher order numerical approximations are used to generate a posteriori error estimators for the finite element approximation.

关键词： Optimal control problem Finite element methods Asymptotic error expansions Defect correction A posteriori error estimates.

An Edge Visual Incremental Perception Framework Based on Deep Semi-supervised Learning for Monitoring Power Transmission Lines

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CSEE Journal of Power and Energy Systems 2023年第2期9卷 759-768页

作者： Jun zhang Jiye Wang Rui Song Guozheng Peng Tianjiao Pu shuhua zhang College of Electrical and Information Engineering Hunan UniversityChangsha 410082China China Electric Power Research Institute Beijing 100192China

In recent years,several efforts have been made to develop power transmission line abnormal target detection models based on edge ***,updates to these models rely on participation of the cloud,which means that network resource shortages can lead to update failures,followed by unsatisfactory recognition and detection performance in practical *** address this problem,this article proposes an edge visual incremental perception framework,based on deep semisupervised learning,for monitoring power transmission *** generation of the initial model using a small amount of labeled data,models trained using this framework can update themselves based on unlabeled data.A teacher-student joint training strategy,a data augmentation strategy,and a model updating strategy are also designed and adopted to improve the performance of the models trained with this *** proposed framework is then examined with various transmission line datasets with 1%,2%,5%,and 10%labeled *** performance enhancement is thus confirmed against traditional supervised learning *** the 10%labeled data training set,the recognition accuracy of the model is improved to exceed 80%,meeting the practical needs of power system operation,and thus clearly validating the effectiveness of the framework.

关键词： Edge intelligence semi-supervised learning transmission lines monitoring visual incremental perception

Analysis of Finite Difference Approximations of an Optimal Control Problem in Economics

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Advances in Applied Mathematics and Mechanics 2019年第6期11卷 1358-1375页

作者： Alexander Lapin shuhua zhang Sergey Lapin Na Yan Institute of Computational Mathematics and Information Technologies Kazan Federal UniversityKazan 420008Russia Coordinated Innovation Center for Computable Modeling in Management Science Tianjin University of Finance and EconomicsTianjin 300222China Department of Mathematics and Statistics Washington State UniversityPullmanWA 99163USA Business School Nankai UniversityTianjin 300071China

We consider an optimal control problem which serves as a mathematical model for several problems in economics and *** problem is the minimization of a continuous constrained functional governed by a linear parabolic diffusion-advection equation controlled in a coefficient in advection *** additional constraint is non-negativity of a solution of state *** construct and analyze several mesh schemes approximating the formulated problem using finite difference methods in space and in *** these approximations keep the positivity of the solutions to mesh state problem,either unconditionally or under some additional constraints to mesh *** allows us to remove corresponding constraint from the formulation of the discrete problem to simplify its *** on theoretical estimates and numerical results,we draw conclusions about the quality of the proposed mesh schemes.

关键词： Mean field game optimal control problem parabolic diffusion-advection equation finite difference methods

Dietary restriction to accompany the aging process in mice Can it be neuroprotective?

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Neural Regeneration Research 2010年第10期5卷 789-795页

作者： Shougang Wei Xiaojuan He Shaojun Yun shuhua zhang Zhongxin Xiao School of Public Health and Family Medicine Capital Medical University Beijing 100069 China

BACKGROUND： Prophylactic dietary restriction （DR）, whether lifelong or started in adulthood,retards the aging process and attenuates cognitive decline in rodents. However, whether the anti-aging and neuroprotective efficacy of DR initiate late in life or accompany the aging process remains ***： The present study sought to：（1） determine if DR could protect against behavioral decline in mice when implemented during the aging process induced by D-galactose and （2） examine neuronal apoptosis in these aged brains and whether DR could block ***, TIME AND SETTING： The randomized controlled animal study. The experiment was performed at the Experimental Animal Center of Capital Medical University and the Laboratory Center of School of Public Health of Captial Medical University of China from April 2006 to October ***： D-galactose （D-gal） was purchased from Beijing Chemical-Regent Company （Beijing, China）. Terminal transferase dUTP nick end labeling （TUNEL） detection kit was obtained from Roche, Germany. Assay kits for antioxidant enzyme activities and malondialdehyde contents were purchased from Jiancheng Institute of Biotechnology （Nanjing, China）. Morris water maze （Friends Honesty Life Sciences Co. Ltd., Hong Kong, China） and Flow Cytometry （Coulter, USA） were used in this ***： A total of 40 male Institute of Cancer Research （lCR） mice, 3 months old, were equally and randomly divided into D-gal treatment, DR treatment, D-gal ＋ DR treatment and normal control groups, and were then randomly assigned to one of two feeding regimens： ad libitum access to food or DR which received a 70% amount of daily food intake as that by ad libitum fed mice. There were two replicates per feeding regimen and mice were fed for 10 weeks,with or without a daily subcutaneous injection of D-gal at 100 mg/*** OUTCOME MEASURES： Animals＇ spatial learning and memory performance were tested in the Morris water maze. Neuronal apoptosis rates were eva

关键词： dietary restriction brain aging D-galactose behavioral performance neuronal apoptosis oxidative stress neural regeneration

Research on Rosewood Micro Image Classification Method Based on Feature Fusion and ELM

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Journal of Renewable Materials 2022年第12期10卷 3587-3598页

作者： Xiaoxia Yang Yisheng Gao shuhua zhang Zhedong Ge Yucheng Zhou School of Information and Electrical Engineering Shandong Jianzhu UniversityJinan250101China School of Architecture and Urban Planning Shandong Jianzhu UniversityJinan250101China

Rosewood is a kind of high-quality and precious wood in *** correct identification of rosewood species is of great significance to the import and export trade and species identification of furniture *** this paper,micro CT was used to obtain the micro images of CTOSS sections,radial sections and tangential sections of 24 kinds of rosewood,and the data sets were *** method was used to reduce the dimension of four features including logical binary pattern,local configuration pattern,rotation invariant LBP,uniform *** four fea-tures and one feature not reducing dimension(rotation invariant uniform LBP)was fused with Gray Level Co-Occurrence Matrix and Tamura features,respectively,a total of five fused features LBP+GLCM+Tamura,LCP+GLCM+Tamura,LBP_(P,R)^(u2)+GLCM+Tamura,LBP_(P,R)^(ri)+GLCM+Tamura and LBP_(P,R)^(riu2)+GLCM+Tamura were *** five fused features were classified by extreme learning machine and BP neural *** clas-sification effect of feature LBP_(P,R)^(u2)+GLCM+Tamura combined with extreme learning machine was the best,and the classification accuracy of CroSS,radial and tangential sections reached 100%,97.63%and 94.72%,respectively,which is 0.83%,2.77%and 5.70%higher than that of BP neural *** classification running time of ELM is less than 1 s,and the classfcation eficiency is *** condusion,the LBP_(P,R)^(u2)+GLCM+Tamura method com-bined with extreme learning machine can be used as a quick and acurate classifier,providing an efficient and feasible class ification method of rosewood.

关键词： Rosewood micro CT feature fusion ELM BP neural network

Sinc Collocation Numerical Methods for Solving Two-Dimensional Gross-Pitaevskii Equations with Non-Homogeneous Dirichlet Boundary Conditions

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Advances in Applied Mathematics and Mechanics 2022年第6期14卷 1302-1332页

作者： Shengnan Kang Kenzu Abdella Macro Pollanen shuhua zhang Liang Wang Coordinated Innovation Center for Computable Modeling in Management Science Tianjin University of Finance and EconomicsTianjin 300222China Department of Mathematics Trent UniversityPeterboroughOntario K9L 7B8Canada Coordinated Innovation Center for Computable Modeling in Management Science Yango UniversityFujian 350015China

This paper presents the numerical solution of the time-dependent Gross-Pitaevskii Equation describing the movement of quantum mechanics particles under non-homogeneous boundary *** to their inherent non-linearity,the equation generally can not be solved ***,a highly accurate approximation to the solutions defined in a finite domain is proposed,using the Crank-Nicolson difference method and Sinc Collocation numerical methods to discretize separately in time and *** Sinc numerical approaches,involving the Sinc Collocation Method(SCM)and the Sinc Derivative Collocation Method(SDCM),are easy to *** results demonstrate that Sinc numerical methods are highly efficient and yield accurate ***,the SDCM decays errors faster than the *** work suggests that the SDCM can be extensively applied to approximate solutions under other boundary conditions to demonstrate its broad applicability further.

关键词： Quantum mechanics spectral method time-dependent partial differential equation boundary value problem.

Integrated transcriptomics and metabolomics analyses provide insights into cold stress response in wheat

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The Crop Journal 2019年第6期7卷 857-866页

作者： Yong Zhao Meng Zhou Ke Xu Jiahao Li Shanshan Li shuhua zhang Xueju Yang Huabei Key Laboratory of Crop Germplasm Hebei Agricultural UniversityBaoding 071000HebeiChina College of Life Sciences Hebei UniversityBaoding 071000HebeiChina

Cold tolerance of crop plants influences survival and productivity under low-temperature conditions. Elucidation of molecular mechanisms underlying low temperature tolerance could be helpful in breeding. In this study, we used integrated transcriptomics and metabolomics analyses to investigate changes in gene/metabolite activity in a winter-hardy wheat cultivar of(cv. Jing 411) when subjected to sold stress. The 223 metabolites mainly enriched during cold acclimation included carbohydrates, flavonoids, and amino *** common metabolites had altered abundance following freezing treatment;six increased and two decreased. Transcriptome analysis revealed that 29,066 genes were differentially expressed in wheat crowns after cold acclimation compared to the nonacclimated control. Among them, 745 genes were up-regulated following freezing treatment, suggesting substantial change in expression of a large quantity of genes upon cold acclimation and freezing treatment, which impacts on the modified *** analysis of gene expression and metabolite profiles revealed that the abscisic acid(ABA)/jasmonic acid(JA) phytohormone signaling and proline biosynthesis pathways were significantly modulated under cold acclimation and freezing treatments. Our results indicated that low-temperature stress induced substantial changes in both transcriptomes and metabolomes. Critical pathways associated with ABA/JA signaling and proline biosynthesis played important roles in regulating cold tolerance in wheat.

关键词： Cold tolerance Transcriptome Metabolome Abscisic acid Jasmonic acid Signaling pathways

Hypergraphs with Spectral Radius between Two Limit Points

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Journal of Mathematical Research with Applications 2018年第1期38卷 1-22页

作者： Shoudong MAN Linyuan LU shuhua zhang Department of Mathematics Tianjin University of Finance and Economics Department of Mathematics University of South Carolina

In this paper, we set ρ;=;4;and ρ′;= β;, where β =-1/6 ·(100 + 12·（69）;);-2/(3·(100+12·（69）;));+4/3≈0.2451223338. We consider connected r-uniform hypergraphs with spectral radius between ρ;and ρ′;and ... 详细信息

关键词： r-uniform hypergraphs spectral radius α-normal