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The mathematical model of wetting angle of heterogeneous nucleation

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science China(Technological sciences) 2004年第4期47卷 391-397页

作者： HUANG Cheng1, SONG Bo1, MAO Jinghong2.& ZHAO Pei3.1. School of Metallurgical and Ecological engineering, University of science and {2. {3., {3. 100083. China 2. School of Material science, University of science and {2. {3., {3. 100083. China 3. Central Iron and Steel Research institute,{13., China 1. School of Metallurgical and Ecological engineering University of Science and Technology Beijing 100083 Beijing China 2. School of Material science University of Science and Technology Beijing 100083 Beijing China 3. Central Iron and Steel Research institute 100081 Beijing China

The heterogeneous nucleation has been analyzed in terms of the thermodynamic theory, and the mathematical model of wetting angle of heterogeneous nucleation has been developed based on the dynamic requirements of hetero- and homogeneous nucleation. With the wetting angel model, the wetting angles of different catalysts in liquid iron have been calculated. The result shows that the wetting angle of most catalysts is smaller than 40, and the value of f() is far less than 1. The wetting angles of TiN, TiC and RE2.3.are smaller, while the wetting angle of MnO is bigger among the ordinary nucleation catalysts. The wetting angles calculated by this model are in agreement with the results of other research work.

关键词： heterogeneous nucleation, mathematical model, wetting angle, undercooling.

A new DNA algorithm to solve graph coloring problem

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Progress in Natural science:Materials International 2007年第6期17卷 733-738页

作者： Jiang Xingpeng1, Li Yin2. Meng Ya3.and Meng Dazhi2.1. National Laboratory of Pattern Recognition,institute of Automation, Chinese Academy of {3.s, {2. 100080, China 2. College of Applied {3.s, {2. University of technology, {2. 10002., China 3. School of {3., beijing institute of technology,{13., China) National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China College of Applied sciences Beijing University of Technology Beijing 100022 China School of science Beijing Institute of Technology Beijing 100081 China

Using a small quantity of DNA molecules and little experimental time to solve complex problems successfully is a goal of DNA computing. Some NP-hard problems have been solved by DNA computing with lower time complexity than conventional computing. However, this advantage often brings higher space complexity and needs a large number of DNA encoding molecules. One example is graph coloring problem. Current DNA algorithms need exponentially increasing DNA encoding strands with the growing of problem size. Here we propose a new DNA algorithm of graph coloring problem based on the proof of four-color theorem. This algorithm has good properties of needing a relatively small number of operations in polynomial time and needing a small number of DNA encoding molecules (we need only 6R DNA encoding molecules if the number of regions in a graph is R).

关键词： DNA computing NP-hard problem graph coloring problem.

Density functional theory study of the reaction paths of reactions of CH3.（O）O2.radicals with HO2.in the gas phase

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Progress in Natural science:Materials International 2006年第12期16卷 1269-1274页

作者： ZHOU Yuzhi~ 1,2., ZHANG Shaowen~1 and LI Qianshu~1**(1. State Key Laboratory of Explosion science and technology,{2.,{3., China 2. beijing institute of Education, beijing 100044, China) [a]State Key Laboratory of Explosion science and technology Beijing Institute of Technology Beijing China [b]beijing institute of Education Beijing China

A DFT study on the reactions between CH_3.（O）O_2.nd HO_2.adicals has been carried out. It is suggested that both the triplet and singlet potential surfaces involve a complex mechanism with the formation of loosely bound intermediate complexes of reactants and products. The reaction prefers to occur on the triplet surface to produce peracetic acid (CH_3.（O）O_2.) and triplet O_2.olecule. The CH_3.（O）O_2. can further convert into CH_3.（O）O and HO radicals.

关键词： acetyl peroxy radicals HO2.radicals reaction mechanism DFT.

Analysis for twinning and slip in face-centered cubic crystals under axisymmetric co-deformation

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science China(Technological sciences) 2006年第5期49卷 521-536页

作者： CHEN Zhiyong1,2. CAI Hongnian1, ZHANG Xinming2. WANG Fuchi1 & TAN Chengwen1,3.1. School of Material science and {3.,{2.,{3., China 2. School of Material science and {3., Central South University, Changsha 410083. China 3. School of Material science and {3., beijing University of Aeronautics and Astronautics, beijing 100083. China 1. School of Material science and engineering Beijing Institute of Technology Beijing 100081 China 2. School of Material science and engineering Central South University Changsha 410083 China 3. School of Material science and engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

The maximum work principle of Bishop-Hill was developed to analyze the axisymmetric co-deformation in face-centered cubic crystals (f.c.c.) for twinning on {111} 112.and slip on {111} 110 systems. The influence of ξ , the ratio of critical re- solved shear stress for twinning to slip, on the yield stress states and corresponding active slip or/and twinning systems for orientations in the standard stereographic triangle of cubic crystal was investigated systematically. The Taylor factors and the anisotropy of yield strength for three important orientations [100], [110] and [111] in orientation space were analyzed. It is found that the yield strength asymmetry for the case of axisymmetric de- formation of tension and compression can be explained based on the microscopic theory of crystal plasticity. The concept of orientation factor for twinning ability was proposed and the deformation mechanism map in the orientation space was established for the case of axisymmetric deformation. The deformation texture formation and development of f.c.c. crystals with low stacking fault energy for axisymmetric tension can be explained qualita- tively on the basis of analyzed results.

关键词： twinning slip face-centered cubic crystals axisymmetric co-deformation Bishop-Hill maximum work principle yield strength anisotropy

Solving the input data in error correc-tion of optical fabrication by finite Fourier coefficient algorithm

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science China(Technological sciences) 2006年第1期49卷 50-60页

作者： CHENG Haobo1,2. SUN Guozheng3.& FENG Zhijing2.1. Department of Optical engineering,{3.,{2., China 2. Department of Precision Instruments and Mechanology, Tsinghua University, {3. 100084, China 3. China North Industries Group Corporation, {3. 100089, China 1. Department of Optical engineering Beijing Institute of Technology Beijing 100081 China 2. Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China 3. China North Industries Group Corporation Beijing 100089 China

A free-form lens (FFL) is a special surface that is difficult to be fabricated. FFL are usually fabricated by computer-controlled optical surfacing (CCOS) technique. During CCOS, the material removal amount is determined by the unit removal function (URF) convoluting with the input data――the dwell time. When the removal amount and the URF are known, how to solve the input data involves the special algorithm――deconvolution. Usually, the input data are solved by virtue of low pass filter or iterative methods. However, an approximation solution would destroy the machining stability nec-essary to perform precisely CCOS. In this paper, to solve the input data, a new method that is based on the finite Fourier coefficient is put forward. It can give a continuous and accurate solution for fabricating choice. Several parameters are simulated, which influ-ence the process of CCOS, and evaluating on the effect of the method is also carried out. Experimental results verify that this method is suitable for guiding the manufacturing of high precision FFL.

关键词： optical fabrication, computer controlled optical surfacing, free-form lens, finite Fourier coefficient, error correction.

Study on Transformation of CaO-Al_2._3.SiO_2.MgO System Inclusions in ZG06Cr13.i4Mo Stainless Steel

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Journal of Iron and Steel Research International 2011年第S2期18卷 341-346页

作者： LIU Jian-hui1,3. DONG Han1,3. ZHU Rong2. LI Shi-qi2.(1. institute for Structural Materials,Central Iron and Steel Research institute,{2.,China 2. School of Metallurgical and Ecological {3.,University of science and technology beijing, beijing 100083.China 3. National {3. Research Center of Advanced Steel technology,{2.,China) Cent Iron & Steel Res Inst Inst Struct Mat Beijing 100081 Peoples R China Univ Sci & Technol beijing Sch Met & Ecol Engn Beijing 100083 Peoples R China Natl Engn Res Ctr Adv Steel Technol Beijing 100081 Peoples R China

This paper aims at generally studying on the inclusions of ZGG06Cr13.i4Mo ultra-low carbon stainless steel used for large scale hydraulic turbine sets. On the basis of analysis the industrial test samples, thermodynamic software FactSage is used to study inclusions transformation process in CaO-SiO2.Al2.3.MgO system while stainless steel is been smelting. The results illustrate the inclusions melting points and plasticity variation law. The reasonable inclusions plasticity controlling area is found out in low melting point. The melting point is up to 12.0℃ While MgO weight concentration is 10% in CaO-SiO2.Al2.3.MgO system, SiO2. Al2.3.and CaO in inclusions are in weight concentration range of 50-70%, 10-2.% and 10-40%, respectively. For purpose of gaining low melting point inclusions, silicon alumina radio in deoxidant should be controlled between 2.5 for ultra-low carbon stainless steel refining in industry.

关键词： ZG06Cr13.i4Mo stainless steel low melting point inclusion thermodynamic calculation

On the periodic solutions of a type of differential-iterative equations

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Chinese science Bulletin 1998年第3期43卷 204-206页

作者： GE Weigao 1, LIU Zhengrong 2.and YU Yuanhong 3.1. Department of Applied Mathematics, beijing institute of technology, beijing 100081, China 2. Department of Mathematics, Yunnan University, Kunming 650091, China 3. {2. of Applied Mathematics, C Department of Applied Mathematics Beijing Institute of Technology Beijing China Department of Mathematics Yunnan University Kunming China institute of Applied Mathematics Chinese Academy of Sciences Beijing China

Sufficient conditions for the existence of periodic solutions to a type of nonautonomous differential_iterative equations are given.

关键词： differential_iterative equation periodic solution fixed point.

Complete quantum circuit of Haar wavelet based MRA

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Chinese science Bulletin 2005年第16期50卷 1796-1798页

作者： HE Yuguo1,2.& SUN Jigui1,3.1. College of computer science and {2., Jilin University, Changchun 13.012. China 2. Department of computer science and engineering, beijing institute of technology, beijing 100081, China 3. Key Laboratory of Computation and Knowledge engineering of Min-istry of Education, Jilin University, Changchun 13.012. China College of computer science and {2. Jilin University Changchun 130012 China

Wavelet analysis has applications in many ar- eas, such as signal analysis and image processing. We pro- pose a method for generating the complete circuit of Haar wavelet based MRA by factoring butterfly matrices and con- ditional perfect shuffle permutation matrices. The factoriza- tion of butterfly matrices is the essential part of the design. As a result, it is the key point to obtain the circuits of I 2. ⊕ W ⊕ I 2. ? 2. ?2. In this paper, we use a simple means to de- velop quantum circuits for this kind of matrices. Similarly, the conditional permutation matrix is implemented entirely, combined with the scheme of Fijany and Williams. The cir- cuits and the ideas adopted in the design are simple and in- telligible.

关键词：量子计算量子算法量子电路 Haar微波 MRA

Research progress in synthesis and catalysis of polyoxometalates

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Progress in Natural science:Materials International 2005年第5期15卷 385-394页

作者： GONG Yun1, HU Changwen1* and LIANG Hong2.1. Department of Chemistry, School of science, the institute for Chemical Physics,{2.,{3., China 2. Chemical Industry Press, beijing 10002., China) Department of Chemistry School of Science the Institute for Chemical Physics Beijing Institute of Technology Beijing 100081 China Chemical Industry Press Beijing 100029 China

Recent progress in the synthetic chemistry and catalysis of polyoxometalates (POMs) is reviewed. The novel POMs and their derivatives emerging in nearly three years (2.02.2.04) are introduced, including POMs with novel structure, POMs-organic hybrid compounds and host-guest complexes. Our review is focused on the elaboration of POMs' supramolecular chemistry.

关键词： polyoxometalates hybrid host-guest structure supramolecule catalysis.