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Sol-gel preparation and Infrared radiation property of Boron-substituted Cordierite Glass-ceramics

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Journal of Materials Science & Technology 2010年第5期26卷 445-448页

作者： Shuming Wang and Fenghua Kuang School of Materials Science and engineering,University of Science & Technology Beijing,Beijing 100083,china School of Materials Science and engineering University of Science & Technology Beijing Beijing 100083 China

Boron for aluminum substitution in the cordierite structure has been examined by sol-gel preparation of different samples along the compositional junction Mg2Al4-xBxSi5O18 with x=0,0.5,1,*** increasing the x value from 0 to 1.5 the crystallization behavior changed *** amount B2O3 doping can promote the sintering of amorphous cordierite gel,effectively restrain the precipitation of μ-cordierite and enhance the crystallization of α-*** substitution of B3＋ for Al3＋ in cordierite crystal structure can effectively improve the near-infrared spectral emissivity of this cordierite based glass-ceramics.

关键词： Sol-gel Glass-ceramics Infrared radiation B3+ substitution Solid solution

TWO-WEIGHT NOrM INEQUALITY FOr IMAGINArY pOWErS OF A LApLACE OpErATOr

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Journal of Systems Science & Complexity 2006年第3期19卷 403-408页

作者： Jianlin ZHANG department of Mathematics and physics,Zhongyuan Institute of Technology,Zhengzhou 450007,china department of Mathematics,Beijing Institute of Technology,Beijing 100081,china. department of Mathematics and physics Zhongyuan Institute of Technology Zhengzhou China department of Mathematics Beijing Institute of Technology Beijing China

We study two-weight norm inequality for imaginary powers of a Laplace operator in r^n, n ≥ 1, especially from weighted Lebesgue space Lv^p（r^n） to weighted Lebesgue space Lμ^p（r^n）, where 1 〈 p 〈 ∞. We prove that the two-weighted norm inequality holds whenever for some t 〉 1, （μ^t, v^t） ∈ Ap, or if （μ, v） ∈Ap, where μ and v^-1/（p-1） satisfy the growth condition and reverse doubling property.

关键词： Ap condition Laplace operator weighted norm inequality.

Synthesis and purification of trialkyl compounds of gallium and indium

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rare Metals 2002年第1期21卷 1-6页

作者： SHU Wangen, ZHOU Zhongcheng and LI Xiong Chemistry and Chemical engineering College, Central South University, Changsha 410083, china Chemistry and Chemistry engineering College Central South University Changsha 410083 Chemistry and Chemical engineering College Central South University Changsha 410083

The The research progress in trialkyl compounds of gallium andindium was discussed from two aspect, one was the chemical synthesisof the compounds and the other was the purification of them. Thereare three synthesis routes be- ing reported in the first aspect, *** route staring form pure metal, the route starting from the puremetal trihalides, and the electrochemical route. In the secondaspect, the purifying methods of decomposition-distillation and zonerefining were reviewed.

关键词： trialkyl compounds gallium nd indium synthesis purification

The General Machining process Simulator GMpS

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Journal of Systems engineering and Electronics 1994年第3期5卷 73-79页

作者： Xiao Tianyuan, Yang Gang & Li Xin (department of Automation, Tsinghua University, Beijing, china, 100084) department of Automation Tsinghua University Beijing China 100084

Automated manufacturing system is characterized by flexibility. It aims at producing a variety of products with virtually no time loses to change over from one part to the next. In this paper, the Machining process Simulator GMpS is introduced, which can be used as a supported environment for machining process. It can be executed off-line or on-line in manufacturing systems in order to predict the collisions of tool with machined workpieces, fixtures or pallets. First, the functional model of GMpS is described, then adopted critical techniques in the simulator are introduced. Finally, an application of GMpS in CIMS ErC of china is presented.

关键词： Machining process simulator Modeling Front End DNC NC code translator 3D animation detecting collision.

Exponential sums over primes in short intervals

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Science china Mathematics 2006年第5期49卷 611-619页

作者： LIU Jianya, Lu Guangshi & ZHAN Tao department of Mathematics, Shandong University, Jinan 250100, china department of Mathematics Shandong University Jinan China

In this paper we establish one new estimate on exponential sums over primes in short intervals. As an application of this result, we sharpen Hua's result by proving that each sufficiently large integer N congruent to 5 modulo 24 can be written as N = p12+p22+p32+p42+p52, with |pj-(N/5)^(1/2)|≤U = N1/2-1/20+ε, where pj are primes. This result is as good as what one can obtain from the generalized riemann hypothesis.

关键词： exponential sums over primes circle method Waring-Goldbach problems.

FOrCED WAVE prOpAGATION IN VISCOELASTIC CABLE WITH SMALL SAG

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Acta Mechanica Solida Sinica 2001年第2期14卷 147-154页

作者： Li Yinghui Jian Kailin~1 Gao Qing Yin Xuegang~1 (department of Applied Mechanics and engineering, Southwest Jiaotong University, Chengdu 610031, china) (1 State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400044, china) Dept. of Appl. Mechanics and Eng. Southwest Jiaotong University Chengdu 610031 China Stt. Key Lab. of Mech. Transmission Chongqing University Chongqing 400044 China

Based on the linear viscoelastic differential constitutive law andcable structural model, the coupled longitudinal-transverse wavesthat propagate along a viscoelastic cable with small curvature isinvesti- gated. A mathematical model is presented that describes thethree-dimensional nonlinear response of a vis- coelastic cable. Anasymptotic form of this model is obtained for the linear response ofcables having small equilibrium curvature.

关键词： viscoelastic cable small equilibrium curvature cut-off frequency

Solution of an Inverse problem of Heat Conduction of 45 Steel with Martensite phase Transformation in High pressure during Gas Quenching

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Journal of Materials Science & Technology 2002年第4期18卷 372-374页

作者： Heming CHENG, Tianchun HE and Jianbin XIEdepartment of engineering Mechanics, Kunming University of Science and Technology, Kunming 650093, china Dept. of Eng. Mech. Kunming Univ. of Sci. and Technol. Kunming 650093 China

In order to simulate thermal strains, thermal stresses, residual stresses and microstructure of the steel during gas quenching by means of the numerical method, it is necessary to obtain an accurate boundary condition of temperature field. The surface heat transfer coefficient is a key parameter. The explicit finite difference method, nonlinear estimation method and the experimental relation between temperature and time during gas quenching have been used to solve the inverse problem of heat conduction. The relationship between surface temperature and surface heat transfer coefficient of a cylinder has been given. The nonlinear surface heat transfer coefficients include the coupled effects between martensitic phase transformation and temperature.

关键词： 45 steel phase transformation Heat conduction

Different-periodic Travelling Wave Solutions for Nonlinear Equations

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Communications in Theoretical physics 2004年第4期41卷 481-486页

作者： YE Li-Jun~1 LIN Ji~(1,2)1 department of physics,Zhejiang Normal University,Jinhua 321004,china2 physics department,Shanghai Jiao Tong University,Shanghai 200030,china department of physics Zhejiang Normal University Jinhua 321004 China physics department Shanghai Jiao Tong University Shanghai 200030 China

Using Jacobi elliptic function linear superposition approach for the(1+1)-dimensional Caudrey-Dodd-Gibbon-Sawada-Kotera(CDGSK)equation and the(2+1)-dimensional Nizhnik-Novikov-Veselov(NNV)equation,many new periodic travelling wave solutions with different periods and velocities are obtained based on the knownperiodic *** procedure is crucially dependent on a sequence of cyclic identities involving Jacobi ellipticfunctions sn(ξ,m),cn(ξ,m),and dn(ξ,m).

关键词： linear superposition nonlinear equation travelling wave solution

On the Abundance of Chaotic Behavior for Generic One-parameter Families of Maps

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Acta Mathematica Sinica,English Series 1996年第4期12卷 398-412页

作者： Zheng Zhiming department of Mathematics peking University Beijing, 100871 china department of Mathematics Peking University Beijing China

In this paper, we want to show the abundance of chaotic systems with absolutely continuous probability measures in the generic regular family with perturbable points. More precisely, we prove that if fa:I→I, a∈p is a regular family satisfying some conditions described in the next section, then there exists a Borel set Ω(?)p of positive Lebesgue measure such that for every a∈Ω, fa admits an absolutely continuous invariant probability measure w.r.t. the Lebesgue measure. The idea of proof in this paper, as compared with that shown in [1] and [7], follows a similar line.

关键词： Chaos Generic regular family probability measure