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Thermal Insulation and Strength of Autoclaved Light Concrete

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Journal of Wuhan university of Technology(Materials Science) 2011年第1期26卷 132-136页

作者：杨若冲吴智深 School of Transportation Southeast University institute of Urban Engineering Science & Technology Southeast University

The primary objective of this study was to develop an autoclaved light concrete （ALC） material with ultra-thermal insulation property and to investigate the relationship between its physical characteristics and mechanical properties. Through tests of dry bulk density and compressive strength, relationship of physical characteristics and mechanical properties of samples were studied, resulting in a material with ultra-thermal insulation property. Scanning electron microscope （SEM） and energy-dispersive X-ray spectroscopy （EDX） were applied to analyze the micro-morphology and elemental composition of samples. To identify the product phases, X-ray diffraction （XRD） was engaged. The test results showed that compressive strength and thermal coefficient were reduced with the increasing of aluminum powder within the mixtures. As a result the optimal thermal coefficient and compressive strength of samples were improved to 0.061 W/（m·k） and 1.2 MPa, respectively. SEM, EDX and XRD analyses showed that calcium silicate hydrate and tobermorite crystal were main resultant phases.

关键词： autoclaved light concrete ultra-thermal insulation microscopic appearance and phase analysis tobermorite crystal

Normality and shared values concerning differential polynomials

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Science china mathematics 2010年第3期53卷 749-754页

作者： LEI ChunLin 1 & FANG MingLiang 2, 1 Department of applied mathematics, South china Agricultural {3., Guangzhou 510642, china 2 institute of applied mathematics, South china Agricultural {3., Guangzhou 510642, china 1. Department of applied mathematics South China Agricultural University Guangzhou 510642 China2. Institute of Applied Mathematics South China Agricultural University Guangzhou 510642 China

Let F be a family of functions meromorphic in a domain D, let P be a polynomial with either deg P≥3.or deg P = 2 and P having only one distinct zero, and let b be a finite nonzero complex number. If, each pair of fun... 详细信息

关键词： meromorphic function normality shared value

Observations favor the crossing of phantom divide lines

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Science china(Physics,mechanics & Astronomy) 2010年第3期53卷 562-566页

作者： HUANG TieTie1,2,3. WU PuXun2,3.& YU HongWei2,3.1Department of Physics, Xiangnan College, Chenzhou 423.00, china 2Department of Physics and institute of Physics, Hunan Normal university, Changsha 410081, china 3.ey Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education, Hunan Normal university, Changsha 410081, china 1. Department of Physics Xiangnan College Chenzhou 423000 China2. Department of Physics and Institute of Physics Hunan Normal University Changsha 410081 China3. Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education Hunan Normal University Changsha 410081 China

Using three different parameterized dark energy models, we reconstruct the properties of dark energy from the latest 3.7 Sne Ia, CMB and BAO with the present matter density, Ωm0, given prior. We find that, when Ωm0 is not small, for example, Ωm0 = 0.28 or 0.3., an evolving dark energy with a crossing of phantom divide line is favored and this conclusion seems to be model independent. We also find that the evolving properties of dark energy become more and more evident with the increase of Ωm0 given prior.

关键词： cosmology auelerating expansion dark energy

BIVARIATE RATIONAL IN TERPOLANTS WITHRECTANGLE-HOLE-STRUCTURE

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Journal of Computational mathematics 1999年第1期17卷 1-14页

作者： Jie-qing Tan(institute of applied mathematics, Hefei {3. Of Technology, Hefei 23.009, china) Hefei Univ Technol Inst Appl Math Hefei 230009 Peoples R China

Bivariate vector valued rational interpolants are established by means of Thiele-type branched continued fractions and Samelson inverse over rectangular grids with holes, characterisation theorem with topologic struct... 详细信息

关键词： branched continued fraction interpolation vector-grid

NUMERICAL CALCULATION OF DILUTE GAS-PARTICLE FLOWS IN A CYLINDRICAL CONTAINER WITH A ROTATING COVER

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Journal of Hydrodynamics 1990年第3期2卷 52-62页

作者： Ding Xue-dong Shanghai university of Technology,Shanghai institute of applied {3. And mechanics,Shanghai 200072,P.R.china Xu Xue-zi Zhejiang university,Hangzhou 3.0027,P.R.china

A new computing technique is described for the solution'of dilute gas-particle fluid flow *** com- mon SIMPLE method is used for the calculation of the gas phase,but for the calculation of the particle phase the MacCormack method(80 style)is *** the technique for gas-particle flows in a rotating cylindrical con- tainer,the field distributions of both phases are *** important parameter Sk(Stokes number)is taken re- spectively as 0.01,0.1 and *** results show the influence of Sk on the *** collisions between particles and the side wall of the container are predicted when Sk=1.

关键词： Flow NUMERICAL CALCULATION OF DILUTE GAS-PARTICLE FLOWS IN A CYLINDRICAL CONTAINER WITH A ROTATING COVER GAS

MIXED FINITE ELEMENT METHODS FOR A STRONGLYNONLINEAR PARABOLIC PROBLEM

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Journal of Computational mathematics 1999年第2期17卷 209-220页

作者： Yan-ping Chen(Department of mathematics, Nanjing university, Naming 210008, china {3. ofComputational and applied mathematics, Xiangtan university, Hunan 411105, china) 南京大学数学系江苏南京

A mixed finite element method is developed to approximate the solution of a strongly nonlinear second-order parabolic problem. The existence and uniqueness of the approximation are demonstrated and L-2-error estimates... 详细信息

关键词： finite element method nonlinear parabolic problem

NUMERICAL SIMULATION OF THE DISPERSION IN OSCILLATING FLOWS WITH REVERSIBLE AND IRREVERSIBLE WALL REACTIONS

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Journal of Hydrodynamics 2009年第4期21卷 482-490页

作者： ZHANG Dao-xiang LU Zhi-ming LIU Yu-lu NG Chiu-On Shanghai institute of applied mathematics and {3. Shanghai University Shanghai 200072 China College of mathematics and Computer Science Anhui Normal University Wuhu 241000 China Department of Mechanical Engineering The University of Hong Kong Hong Kong China

This is a study on the mass transport of a solute or contaminant in oscillating flows through a circular tube with a reactive wall layer. The reaction consists of a reversible component due to phase exchange between the flowing fluid and the wall layer, and an irreversible component due to absorption into the wall. The short-time dispersion characteristics are numerically investigated, incorporating the coupling effects between the flow oscillation, sorption kinetics, and retardation due to phase partitioning. The effects of various dimensionless parameters e.g., Da （the Damkoehler number）, α （phase partitioning number）, F （dimensionless absorption number）, and δ （dimensionless Stokes boundary layer number） on dispersion are discussed. In particular, it is found that there exist trinal peaks of the breakthrough curves in some cases.

关键词： dispersion flow oscillation wall reactions

ORDER PROPERTIES AND CONSTRUCTION OF SYMPLECTIC RUNGE-KUTTA METHODS

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Journal of Computational mathematics 2000年第6期18卷 645-656页

作者： Shou-fu Li (institute for Computational and applied mathematics, Xiangtan {3., Xiangtan 411105, china) 湘潭大学湖南湘潭 411105

The main results of this paper are as follows: (1) Suppose an s stage Runge-Kutta method is consistent, irreducible, non-confluent and symplectic. Then this method is of order at least 2p + l(1 less than or equal to p less than or equal to s - 1) provided that the simplifying conditions C(p) (or D(p) with non-zero weights) and B(2p + l) hold, where 1 0, 1, 2. (2) Suppose an s stage Runge-Kutta method is consistent, irreducible and non-confluent, and satisfies the simplifying conditions C(p) and D(p) with 0 s. Then this method is symplectic if and only if either p = s or the nonlinear stability matrix M of the method has an (s - p) x (s - p) chief submatrix (M) over cap = 0. (3. Using the results (1) and (2) as bases, we present a general approach for the construction of symplectic Runge-Kutta methods, and a software has been designed, by means of which, the coefficients of s stage symplectic Runge-Kutta methods satisfying C(p),D(p) and B(2p + l) can be easily computed, where 1 I P less than or equal to s, 0 less than or equal to l less than or equal to 2, s less than or equal to 2p + l less than or equal to 2s.

关键词： numerical analysis symplectic Runge-Kutta methods simplifying conditions order results

Conformal isoparametric hypersurfaces with two distinct conformal principal curvatures in conformal space

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Science china mathematics 2010年第4期53卷 953-965页

作者： NIE ChangXiong 1,2,LI TongZhu 3.HE YiJun 4 & WU ChuanXi 5 1 Faculty of mathematics and Computer Sciences,Hubei university,Wuhan 43.062,china 2 School of Mathematical Sciences,Peking university,Beijing 100871,china 3.Faculty of Sciences,Beijing institute of Technology,Beijing 100081,china 4 School of Mathematical Sciences,Shanxi university,Taiyuan 03.006,china 5 institute of mathematics,Hubei university,Wuhan 43.062,china 1. Faculty of mathematics and Computer Sciences Hubei University Wuhan 430062 China2. School of Mathematical Sciences Peking University Beijing 100871 China3. Faculty of Sciences Beijing Institute of Technology Beijing 100081 China4. School of Mathematical Sciences Shanxi University Taiyuan 030006 China5. Institute of Mathematics Hubei University Wuhan 430062 China

The conformal geometry of regular hypersurfaces in the conformal space is *** classify all the conformal isoparametric hypersurfaces with two distinct conformal principal curvatures in the conformal space up to confor... 详细信息

关键词： Lorentz conformal geometry conformal invariants conformal isoparametric hypersurfaces