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Composition Operators on the Bloch Space of Several Complex Variables

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Acta Mathematica Sinica,English Series 2000年第1期16卷 85-98页

作者： jihuai shi Luo Luo {2. of mathematics,University of science and technology of china,Heifei 2.0036,P.R.china Fax:(0551)3631760 department of mathematics University of Science and Technology of China Heifei 230036 P.R. China

In this paper,we study the boundedness and compactness of composition operator C on the Bloch space β（Ω）,Ω being a bounded homogeneous *** Ω=Bn,we give the necessary and sufficient conditions for a composition o... 详细信息

关键词： Bloch space Composition operator Bergman metric

Sharp Estimates in Bergman and Besov Spaces on Bounded Symmetric Domains

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Acta Mathematica Sinica,English Series 2002年第3期18卷 499-504页

作者： Guang Bin REN Ji Huai shi department of {2.. University of science and technology of china. hefei 2.002.. P. R. china department of mathematics University of Science and Technology of China Hefei P. R. China

Sharp estimates of the point-evaluation functional in weighted Bergman spaces L_~p(Ω, dv_) and for the point-evaluation derivalive functional in Besov spaces B^p(Ω) are obtained for bounded symmetric domains Ω in C^n.

关键词： Bergman spaces Besov spaces Bounded svmmetric domains

MACKEY TOPOLOGIES OF HARDY SPACES AND BERGMAN SPACES IN SEVERAL COMPLEX VARIABLES

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Chinese science Bulletin 1989年第19期34卷 1585-1589页

作者：史济怀 department of mathematics University of Science and Technology of China Hefei

B_n denotes the unit ball of C^n,(?)B_n its boundary, γ_n,and σ_n the normalized Lebesgue measures on B_n and (?)B_n respectively, H(B_n) the class of all functions holomorphic in B_n.

关键词： Mackey topology dual locally convex

Association of physical activity with risk of chronic kidney disease in china:A population-based cohort study

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Journal of Sport and Health science 2024年第2期13卷 204-211页

作者： Kexiang shi Yunqing Zhu Jun Lv Dianjianyi Sun Pei Pei Huaidong Du Yiping Chen Ling Yang Bing Han Rebecca Stevens Junshi Chen Zhengming Chen Liming Li Canqing Yu {2. Kadoorie Biobank collaborative group department of Epidemiology&Biostatistics School of Public HealthPeking University Health Science CenterBeijing 100191China Peking University Center for Public Health and Epidemic Preparedness&Response Beijing 100191China Key Laboratory of Epidemiology of Major Diseases(Peking University) Ministry of EducationBeijing 100191China Clinical Trial Service Unit&Epidemiological Studies Unit(CTSU) Nuffield Department of Population HealthUniversity of OxfordOxford OX37LFUK Medical Research Council Population Health Research Unit at the University of Oxford Oxford OX37LFUK NCDs Prevention and Control department Henan Center for Disease Control and PreventionZhengzhou 450016China china National Center for Food Safety Risk Assessment Beijing 100022China 不详

Background:Information on the association between physical activity(PA)and the risk of chronic kidney disease(CKD)is *** aimed to explore the associations of total,domain-specific,and intensity-specific PA with CKD and its subtypes in ***:The study included 475,376 adults from the china Kadoorie Biobank aged 30-79 years during 2.04-2.08 at *** interviewer-administered questionnaire was used to collect the information about PA,which was quantified as metabolic equivalent of task hours per day(MET-h/day)and categorized into 4 groups based on *** regression was used to analyze the association between PA and CKD ***:During a median follow-up of 12.1 years,5415 incident CKD cases were documented,including 1159 incident diabetic kidney disease(DKD)cases and 362.incident hypertensive nephropathy(HTN)*** PA was inversely associated with CKD risk,with an adjusted hazard ratio(HR,95%confidence interval(95%CI))of 0.83(0.75-0.92.for incident CKD in the highest quartile of total PA as compared with participants in the lowest *** results were observed for risk of DKD and HTN,and the corresponding HRs(95%CIs)were 0.75(0.58-0.97)for DKD risk and 0.56(0.37-0.85)for HTN *** nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA were significantly associated with a decreased risk of CKD,with HRs(95%CIs)of 0.80(0.73-0.88),0.85(0.77-0.94),and 0.85(0.76-0.95)in the highest quartile,***:PA,including nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA,was inversely associated with the risk of CKD,including DKD,HTN,and other CKD,and such associations were dose dependent.

关键词： Chronic kidney disease Domain Intensity Physical activity

The Riemannian Manifolds with Boundary and Large Symmetry

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Chinese Annals of mathematics,Series B 2010年第3期31卷 347-360页

作者： Zhi CHEN Yiqian shi Bin XU department of mathematics University of Science and Technology of China Hefei 230026 China. department of mathematics University of Science and Technology of China Hefei 230026 China.

Seventy years ago, Myers and Steenrod showed that the isometry group of a Riemannian manifold without boundary has a structure of Lie group. In 2.07, Bagaev and Zhukova proved the same result for a Riemannian orbifold. In this paper, the authors first show that the isometry group of a Riemannian manifold M with boundary has dimension at most 1/2.dim M（dim M - 1）. Then such Riemannian manifolds with boundary that their isometry groups attain the preceding maximal dimension are completely classified.

关键词： Riemannian manifold with boundary Isometry Rotationally symmetric metric Principal orbit

Synthesis and intrinsic blue fluorescence study of hyperbranched poly(ester-amide-ether)

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science china Chemistry 2010年第12期53卷 2452-2460页

作者： ZHANG Yong,FU Qi & shi WenFang CAS Key Laboratory of Soft Matter Chemistry department of Polymer {2. and Engineering,University of {2. and technology of china,hefei 2.002.,china 1. CAS Key Laboratory of Soft Matter Chemistry department of Polymer science and Engineering University of Science and Technology of China Hefei 230026 China

A series of hyperbranched poly(ester-amide-ether)s (H-PEAEs) were synthesized via the A2.CB3 approach by the self-transesterification of ethyl ester-amide-ethers end-capped with three hydroxyl groups and ethyl ester group at two *** molecular structures were characterized with 1H NMR and FT-IR *** number average molecular weights were estimated by GPC analysis to possess bimodal wide distribution from 1.57 to *** strong inherent blue fluorescence was observed at 330 nm for excitation and 390 nm for ***,the emission intensity and fluorescence quantum yield increased along with the incorporated ether chain length,as well as almost linearly with the H-PEAE concentration in an aqueous *** comparing the fluorescence performance,the linear poly(ester-amide-ether) (L-PEAE) and hyperbranched poly(ester-amide) (H-PEA) were *** results showed that the coexistence of ether bond and carboxyl group in the molecular chain was essential for generating the strong ***,the compact backbone of H-PEAE would be propitious to the enhancement of fluorescence properties.

关键词： synthesis self-transesterification hyperbranched poly(ester-amide-ether) fluorescence property

INCOMPRESSIBLE MULTI-RELAXATION-TIME LATTICE BOLTZMANN MODEL IN 3-D SPACE

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Journal of Hydrodynamics 2010年第6期22卷 782-787页

作者： DU Rui shi Bao-chang department of mathematics South East University Nanjing 210096 China department of mathematics Huazhong University of Science and Technology Wuhan 430074 China

Multi-Relaxation-Time Lattice Boltzmann Method （MRT LBM） is of better numerical stability and has attracted more and more research interests. The previous MRT LBM included artificial compressible effects. To overcome the disadvantage, an incompressible MRT LBM has been proposed in two dimensions recently. In this article, we present incompressible MRT LBMs in 3-D space, with example of nineteen-velocity. The equilibria in momentum space are derived from an earlier incompressible Lattice Bhatnagar-Gross-Krook （LBGK） model proposed by Guo et al.. Through the Chapman-Enskog （C-E） expansion, the incompressible Navier-Stokes （N-S） equations can be recovered without artificial compressible effects. Simulations of a lid-driven cavity flow in three dimensions with Re = 1 000, 2.000 and 3 2.0 are performed. The simulation results agree with the existing data and clearly demonstrate better numerical stability of the presented model over the incompressible LBGK model.

关键词： incompressible flow Multi-Relaxation-Time (MRT) Lattice Boltzmann Method (LBM)

AN IMPLICIT SCHEME FOR INCOMPRESSIBLE LBGK MODEL

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Journal of Hydrodynamics 2005年第3期17卷 330-337页

作者： DURui shiBao-chang WANGGuang-chao LIUHong-juan departmentofmathematics HuazhongUniversityofScienceandTechnologyWuhan430074China departmentofmathematics HuazhongUniversityofScienceandStateKeyLaboratoryofCoalCombustionHuazhongUniversity430074China／／TechnologyWuhan430074ChinaofScienceandTechnologyWuhan

In this paper, an implicit scheme (also called the θ method) was proposed for the Lattice Bhatager-Gross-Krook (LBGK) model simulating incompressible flows. The new parameter θ made the model more flexible. Through the Chapman-Enskog procedure the impressible Navie-Stokes equations could be recovered with the coupled kinetic viscosity. Boundary conditions were treated briefly and it kept the numerical accuracy of the Lattice Boltzmann Method (LBM). The two-dimensional Poiseuille flow was simulated with different values of the parameters. It is found that the numerical accuracy and stability of the implicit scheme can be improved if some adaptable parameters are chosen.

关键词： Lattice Boltzmann Method (LBM) implicit scheme θ-Lattice Bhatager-Gross-Krook (LBGK) model Poiseuille flow

Finite groups in which elements of the same order outside the center are conjugate

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science china {2. 2007年第10期50卷 1493-1500页

作者： Xing-zhong YOU~1 Guo-hua QIAN~2.Wu-jie shi~(3+) ~1 School of mathematics and Computing {2.,Changsha University of {2. and technology,Changsha 410076,china ~2.department of mathematics,Changshu Institute of technology,Changshu 2.5500,china ~3 School of mathematics,Suzhou University,Suzhou 2.5006,china 1. School of mathematics and Computing science Changsha University of Science and Technology Changsha 410076 China 2. department of mathematics Changshu Institute of Technology Changshu 215500 China 3. School of mathematics Suzhou University Suzhou 215006 China

We prove that if G is a finite group in which the elements of the same order outside the center are conjugate, then either G is abelian or G ≌ S3.

关键词： finite group, rational group, conjugacy class