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Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2, ZHANG Jiao qiang 3. (1. department of Chemistry,Northwest university, Xi′an 710065, china 2. department of Chemistry and chemical Engineering, Baoji College of Arts and science, Baoji 721007, china 3. department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

A MODIFIED ALGORITHM OF FINDING AN ELEMENT OF CLARKE GENERALIZED GRADIENT FOR A SMOOTH COMPOSITION OF MAX-TYPE FUNCTIONS A MODIFIED ALGORITHM OF FINDING AN ELEMENT OF CLARKE GENERALIZED GRADIENT FOR A SMOOTH COMPOSITION OF MAX-TYPE FUNCTIONS

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Journal of Computational Mathematics 2000年第5期18卷 513-520页

作者： Yan Gao (department of Basic science, china {3. of Mining and technology-Beijing, Beijing 100083. china) （北京）中国矿业大学北京 100083

This paper refers to Clarke generalized gradient for a smooth composition of max-type functions of the form: f(x) = g(x, maxj∈J1 f1j(x),''', maxj∈Jm fmj(x)), where x ∈Rn, Ji, i = 1,''',m are finite index sets, g and fij,j ∈ Ji, i = 1,... )m, are continuously differentiable on Rm+n and Rn, respectively. In a previous paper) we proposed an algorithm of finding an element of Clarke generalized gradient for f, at a point. In that paper, finding an element of Clarke generalized gradient for f, at a point, is implemented by determining the compatibilities of systems of linear inequalities many times. So its computational amount is very expensive. In this paper) we will modify the algorithm to reduce the times that the compatibilities of systems of linear inequalities have to be determined.

关键词： Nonsmooth optimization Clarke generalized gradient Max-type function.

THE VISCOELASTIC EFFECT ON THE FORMATION OF MESO-GLOBULAR PHASE OF DILUTE HETEROPOLYMER SOLUTIONS

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Chinese Journal of Polymer science 2003年第2期21卷 117-122页

作者： Chi Wu The Open Laboratory of Bond Selective Chemistry department of chemical Physics, university of science and technology of china,{3. china department of Chemistry The Chinese university of Hong Kong Shatin, Hong Kong university of science and technology of{3. Laboratory of Bond Selective Chemistry CAS Hefei 230026

Linear homopolymer chains in poor solvent exist either as individual crumpled single chain globules or asmacroscopic precipitate, depending on whether the solution is in the one- or the two-phase region. However, linearheteropolymer chains in dilute solution might be able to form stable mesoglobules made up of a limited number of chains ifthe degree of amphiphilicity of the chain is sufficiently high and the experimental conditions are appropriate. The self-assembly of block copolymers in a selective solvent is typical of such examples. In practice, the formation of stablemesoglobules can be directly related to the formation of novel polymeric nanopaticles in solution. In this article, we willaddress the formaton of mesoglobular phase not only on the basis of thermodynamics, but also from a kinetic point of view,which leads to the discussion of how viscoelasticity can affect the phase behavior of heteropolymer chains in dilute *** formation and stabilization of several different kinds of novel polymeric nanopedicles will be used to illustrate ourdiscussion.

关键词： Viscoelasticity Mesoglobular phase Heteropolymer Nanoparticle Polymer Dispersion Microphase inversion

Catalytic Asymmetric Cyclopropanation using a New Chiral β-Diketone Cu (Ⅱ) Complex as a Catalyst

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Chinese chemical Letters 1998年第7期9卷 607-608页

作者： Yu XU Zhong Yi WANG and Tian Pa YOU(department of Chemistry, university of science and technology of china, hefei 23.026) department of Chemistry Univ. of Sci./Technology of China Hefei 230026 China

A new chiral β-diketone Cu (Ⅱ) catalyst was synthesized and used for the asymmetric cyclopropanation of styrene with diazoester. A high optical yield (~90%) was achieved. The effect of the structure of substrate on the enantioselectivity was studied. Both chendcal yield and optical yield being reduced when the steric bulky substrate was employed. The reaction mechanism and the chiral model of the transition state are under fufther investigation.

关键词： Asymmetric cyclopropanation β-Diketone Cu (Ⅱ) Complex

The characteristics of arc beam shaping in hybrid plasma and laser deposition manufacturing

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science china(Technological sciences) 2006年第2期49卷 238-247页

作者： ZHANG Hai’ou1, QIAN Yingping1,3. WANG Guilan1 & ZHENG Qiguang2 1. School of Material science and technology, Huazhong university of science and technology, Wuhan 43.074, china 2. Institute of Laser technology and Engineering, Huazhong university of science and technology, Wuhan 43.074, china 3. Mechanical Engineering College, Hubei university of technology, Wuhan 43.068, china School of Material science and technology Huazhong University of Science and Technology

As a new direct metal prototyping technology,the hybrid plasma and laser deposition manufacturing (PLDM) is proposed in this paper. In order to figure out the characteristics of plasma arc beam and mould in the PLDM process of high temperature alloy, the high speed CCD camera is used to obtain the picture around the plasma arc. Afterwards the sketch of picture is clearly obtained. And the effect of laser parameter, such as average power, pulse width, pulse repetition frequency and the angle between laser beam and plasma arc beam on the plasma arc appearance, is studied experimentally. The results show that the modality of plasma arc beam is markedly influenced by laser beam. And the improvements of shape precision and surface state of the layer deposited by PLDM are confirmed.

关键词： plasma hybrid laser, direct deposition, plasma arc beam, molding character, high-temperature alloy.

Highest weight representations of a Lie algebra of Block type

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science china Mathematics 2007年第4期50卷 549-560页

作者： Yue-zhu WU & Yu-cai SU department of Mathematics, Shanghai Jiaotong university, Shanghai 200240, china department of Mathematics, Qufu Normal university, Qufu 273.65, china department of Mathematics, university of science and technology of china, hefei 23.026, china department of Mathematics Shanghai Jiaotong University Shanghai China department of Mathematics Qufu Normal University Qufu China department of Mathematics University of Science and Technology of China Hefei China

For a field $\mathbb{F}$ of characteristic zero and an additive subgroup G of $\mathbb{F}$ , a Lie algebra B(G) of the Block type is defined with the basis {L α,i , c | α ∈ G ?1 ≤ i ∈ ?} and the relations [L α,i , L β,j ] = ((i + 1)β ? (j + 1)α)L α+β,i+j + αδ α, ?β δ i+j,?2 c, [c, L α,i ] = 0. Given a total order ? on G compatible with its group structure, and any Λ ∈ B(G) 0 * , a Verma B(G)-module M(Λ, ?) is defined, and the irreducibility of M(Λ, ?) is completely determined. Furthermore, it is proved that an irreducible highest weight B(?)-module is quasifinite if and only if it is a proper quotient of a Verma module.

关键词： Verma modules Lie algebras of Block type irreducibility 17B10 17B65 17B68

THE FIRST BOUNDARY VALUE PROBLEM FOR STRONGLY DEGENERATE QUASILINEAR PARABOLIC EQUATIONS IN ANISOTROPIC SOBOLEV SPACES

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Acta Mathematica Scientia 2006年第2期26卷 255-264页

作者：招燕燕陈祖墀 department of Mathematics university of science and technology of china Hefei 230026China

This article concerns the existence of weak solutions of the first boundary value problem for a kind of strongly degenerate quasilinear parabolic equation in the anisotropic Sobolev Space. With the theory of anisotrop... 详细信息

关键词： Weak solution strongly degenerate quasilinear parabolic equation 2000 MR Subject Classification 3.K55 3.K60 3.K65

Construct non-graded bi-Frobenius algebras via quivers

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science china Mathematics 2007年第3期50卷 450-456页

作者： Yan-hua WANG & Xiao-wu CHEN department of Applied Mathematics, Shanghai university of Finance and Economics, Shanghai 20043., china department of Mathematics, university of science and technology of china, hefei 23.026, china department of Applied Mathematics Shanghai University of Finance and Economics Shanghai China department of Mathematics University of Science and Technology of China Hefei China

Using the quiver technique we construct a class of non-graded bi-Frobenius algebras. We also classify a class of graded bi-Frobenius algebras via certain equations of structure coefficients.

关键词： quivers bi-Frobenius algebras graded algebras 16W3. 16G20

Facile synthesis of dendrimer-like star-branched poly(isopropylacrylamide) via combination of click chemistry and atom transfer radical polymerization

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science china Chemistry 2010年第12期53卷 2520-2527页

作者： WAN XueJuan,XU Jian & LIU ShiYong CAS Key Laboratory of Soft Matter Chemistry department of Polymer science and Engineering,hefei National Laboratory for Physical sciences at the Microscale,university of science and technology of china,hefei 23.026,china CAS Key Laboratory of Soft Matter Chemistry department of Polymer science and Engineering Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of China Hefei China

We report a facile synthesis method of dendrimer-like star-branched poly(N-isopropylacrylamide) (PNIPAM) via the combination of click chemistry and atom transfer radical polymerization (ATRP) by employing the arm-first ***,the α-azido-ω-chloro-heterodifunctionalized building block,N3.PNIPAM-Cl (G0-Cl),was synthesized via ATRP by 3.azidopropyl 2-chloropropionate as the *** advantage of click chemistry,the first generation (G1) of dendrimer-like star-branched PNIPAM,G1-(Cl)3.was facilely prepared via the click coupling reaction between G0-Cl and *** the construction of second generation (G2) dendrimer-like star-branched PNIPAM,G2-(Cl)6,terminal chloride moieties of G1-(Cl)3.were first converted to azide,and then reacted with excess tripropargylamine to give G1-(alkynyl)6 ;G2-(Cl)6 was subsequently prepared via click reaction between G1-(alkynyl) 6 and *** permeation chromatography (GPC) and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry were employed to confirm the successful construction of dendrimer-like star-branched *** unique thermal phase transition behavior of this dendrimer-like star-branched polymer in aqueous solutions was further investigated by turbidimetry and micro-differential scanning calorimetry (Micro-DSC).

关键词： dendrimer-like branched ATRP click chemistry