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An exploration for the macroscopic physical meaning of entropy

Science china(Technological Sciences) 2010年第7期53卷 1809-1816页

作者： WU Jing1 & GUO ZengYuan2 1 college of Energy and power engineering, Nanjing university of Aeronautics and Astronautics, Nanjing 210016, china 2 Key Laboratory for Thermal Science and power engineering of Ministry of Education, School of Aerospace, Tsinghua university, Beijing 100084, china 1. college of Energy and power engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China2. Key Laboratory for Thermal Science and Power Engineering of Ministry of Education School of Aerospace Tsinghua University Beijing 100084 China

The macroscopic physical meaning of entropy is analyzed based on the exergy (availability) of a combined system (a closed system and its environment), which is the maximum amount of useful work obtainable from the system and the environment as the system is brought into equilibrium with the environment. The process the system experiences can be divided in two sequent sub-processes, the process at constant volume, which represents the heat interaction of the system with the environment, and the adiabatic process, which represents the work interaction of the system with the environment. It is shown that the macroscopic physical meaning of entropy is a measure of the unavailable energy of a closed system for doing useful work through heat interaction. This statement is more precise than those reported in prior literature. The unavailability function of a closed system can be defined as T0S and p0V in volume constant process and adiabatic process, respectively. Their changes, that is, AiTgS) and A (p0V) represent the unusable parts of the internal energy of a closed system for doing useful work in corresponding processes. Finally, the relation between Clausius entropy and Boltzmann entropy is discussed based on the comparison of their expressions for absolute entropy.

关键词： entropy macroscopic physical meaning exergy heat interaction

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Analysis of contact melting around a horizontal elliptical cylinder heat source

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Progress in Natural Science:Materials International 2008年第4期18卷 441-446页

作者： Miao Gong, Wenzhen Chen, Yuansong Zhao, Bo Zhu, Fengrui Sun college of power and Shipping, Naval university of engineering, Wuhan, Hubei 430033, china college of power and Shipping Naval University of Engineering Wuhan Hubei 430033 China

The process of DT-driven contact melting of the solid phase change material (PCM) around a horizontal elliptical cylinder heat source is analyzed. Aiming at the problem existed in the published literature, namely the thickness of boundary layer tends to be infinite at φ= 90°, and considering the difference of normal angle between the horizontal elliptical cylinder surface and the solid-liquid interface of PCM, a new mathematic model is proposed, and the fundamental equations for the melting process are derived with the film theory. The new pressure distribution inside the boundary layer, the variation law of normal angle of the solid-liquid interface, the thickness of the boundary layer and the relationship between the melting velocity and resultant force are obtained. The solutions of the fundamental equations under different elliptical compression coeffcients are analyzed and discussed. It is found that the thickness of the boundary layer obtained by the new model is a finite value and accords with the experimental result at φ = 90°.

关键词： Contact melting Elliptical cylinder Phase change phenomena Heat transfer

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Modelling Immune System:Principles,Models,Analysis and Perspectives

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Journal of Bionic engineering 2009年第1期6卷 77-85页

作者： Xiang-hua Li~1, Zheng-xuan Wang~1, Tian-yang Lu~2, Xiang-jiu Che~11. college of Computer Science and Technology, jilin university, changchun 130012, P. R. china2. college of Computer Science and Technology, Harbin engineering university, Harbin 150001, P. R. china [a]college of Computer Science and Technology Jilin University Changchun 130012 P. R. China [b]College of Computer Science and Technology Harbin Engineering University Harbin 150001 P. R. China

The biological immune system is a complex adaptive *** are lots of benefits for building the model of the immune *** biological researchers,they can test some hypotheses about the infection process or simulate the responses of some *** computer researchers,they can build distributed,robust and fault tolerant networks inspired by the functions of the immune *** paper provides a comprehensive survey of the literatures on modelling the immune *** the methodology perspective,the paper compares and analyzes the existing approaches and models,and also demonstrates the focusing research effort on the future immune models in the next few years.

关键词： immune system modelling agent-based simulation complex adaptive system (CAS) HIV

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On-line Preconcentration and Determination of Trace Metals in Water Samples by Flow Injection Combined with Flame Atomic Absorption Spectrometry via Calix[4]arene Carboxylic Acid Packed Micro-column

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Chemical Research in Chinese Universities 2012年第1期28卷 26-30页

作者： GUO Da-wang, ZHAO Xiao-wei, JIA Qiong and ZHOU Wei-hong college of Chemistry, jilin university, changchun 130012, P. R. china jilin Univ Coll Chem Changchun 130012 Peoples R China

An adsorbent calix[4]arene carboxylic acid was employed as the adsorption material for on-line flow in jection（FI） micro-column preconcentration coupled with flame atomic absorption spectrometry（FAAS） determination of trace heavy metals（Cu, Pb, Co, Ni and Cd）. Parameters such as the pH, loading time and flow rate of sample, and the concentration, volume and flow rate of eluent were optimized. The enrichment factors are 50.0, 56.5, 11.6, 12.1 and 19.1 for Cu, Pb, Co, Ni, and Cd, respectively, and a sample throughput of 20 h–1 was obtained. The limits of de tection for Cu, Pb, Co, Ni, and Cd were in a range of 1.56―3.91 μg/L, and the relative standard deviations（RSDs） were less than 2.76%（n=7）. Furthermore, the proposed method was successfully applied to the determination of Cu, Pb, Co, Ni, and Cd in certified reference materials and various water samples.

关键词： Calixarene carboxylic acid Preconcentration Flow injection Metal ion Flame atomic absorptionspectrometry(FAAS)

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Gabor Filter Optimization Design for Iris Texture Analysis

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Journal of Bionic engineering 2004年第1期1卷 72-78页

作者： Tao Xu 1, Xing Ming 2, Xiaoguang Yang 3 1.college of Mechanical Science and engineering, jilin university, changchun 130022, P.R.china 2.college of Computer Science and Technology, jilin university, changchun 130022, P.R.china 3.Dept of Mathematics and Physics, Dalian Maritime university, Dalian 116026,P.R.china jilin university jilin university Dalian Maritime university

This paper deals with an optimization design method for the Gabor filters based on the analysis of an iris texture model. By means of analyzing the properties of an iris texture image, the energy distribution regularity of the iris texture image measured by the average power spectrum density is exploited, and the theoretical ranges of the efficient valued frequency and orientation parameters can also be deduced. The analysis shows that the energy distribution of the iris texture is generally centralized around lower frequencies in the spatial frequency domain. Accordingly, an iterative algorithm is designed to optimize the Gabor parameter field. The experimental results indicate the validity of the theory and efficiency of the algorithm.

关键词： iris recognition texture analysis receptive profile Gabor filter parameter field optimization method

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Systematic study of the transfer of amino acids across the water/1,2-dichloroethane interface facilitated by dibenzo-18-crown-6

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Science china Chemistry 2004年第1期47卷 24-33页

作者： CHEN Yong, YUAN Yi, ZHANG Meiqin, LI Fei, SUN Peng, GAO Zhao & SHAO YuanhuaState Key Laboratory of Electroanalytical Chemistry, changchun Institute of Applied Chemistry, Chinese Academy of Sciences, changchun 130022, china college of Chemistry and Molecular engineering, Peking university, Beijing 100871, china Lab. of Electroanalytical Chem. Changchun Inst. of Appl. Chem. Chinese Acad. of Sci. Changchun 130022 China Coll. of Chem. and Molecular Eng. Peking Univ. Beijing 100871 China

Facilitated ion transfer reactions of 20 amino acids with dibenzo-18-crown-6 (DB18C6) at the water/1,2-dichloroethane (W/DCE) interfaces supported at the tips of micro- and nano-pipets were investigated systematically using cyclic voltammetry. It was found that there were only 10 amino acids, that is, Leu, Val, lie, Phe, Trp, Met, Ala, Gly, Cys, Gin (in brief), whose protonated forms as cations can give well-defined facilitated ion transfer voltammograms within the potential window, and the reaction pathway was proven to be consistent with the transfer by interfacial complexation/dissociation (TIC/TID) mechanisms. The association constants of DB 18C6 with different amino acids in the DCE (β0), and the kinetic parameters of reaction were evaluated based on the steady-state voltammetry of micro- or nano-pipets, respectively. The experimental results demonstrated that the selectivity of complexation of protonated amino acid by DB18C6 compared with that of alkali metal cations was low, which can be attributed to the vicinal effect arising from steric hindrance introduced by their side group and the steric bulk effect by lipophilic stabilization. Moreover, the association constants and the standard rate constants for different amino acids showed good correlations with their hydrophobicity (π), except Gly and Met, which inferred that the selectivity of such heterogeneous complex reaction for different amino acids with DB18C6, was not only affected by discrimination in binding these ions to the crown ether macro-cycle, but also significantly modified by the ion transfer Gibbs energy which was closely related to the structure of the transferred ions, protonated amino acids.

关键词： micro-/nano-pipet, water/1,2-dichloroethane interface, facilitated ion transfer, cyclic voltammetry, amino acid.

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Analysis of melting driven by friction and temperature difference under sliding plate

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Progress in Natural Science:Materials International 2007年第3期17卷 366-370页

作者： CHEN Wenzhen, ZHAO Yuansong, SUN Fengrui, ZHU Bo and GONG Miao (college of power and Shipping, Naval university of engineering, Wuhan 430033, china) [a]college of power and Shipping Naval University of Engineering Wuhan China

The contact melting processes of phase change material (PCM) under a sliding plate, which is driven by the friction and temperature difference AT, are studied. By using film theory, the fundamental equations for the melting process are derived. The thickness of boundary layer, the pressure distribution inside boundary layer and the mass melting rate of PCM are also obtained with the numerical method. It is found that (1) the larger the temperature difference is, the larger the thickness of boundary layer and the mass melting rate are, and the more asymmetric the pressure distribution is; (2) the quicker the sliding velocity is, the larger the mass melting rate is, the flatter the thickness of boundary layer is, and the more symmetric the pressure distribution is; (3) the results of the contact melting driven together by the friction and temperature difference cannot be obtained by the addition of those driven respectively by the friction and temperature difference.

关键词： friction contact melting sliding plate.

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Use of the modified viral satellite DNA vector to silence mineral nutrition-related genes in plants: silencing of the tomato ferric chelate reductase gene, FRO1, as an example

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Science china(Life Sciences) 2008年第5期51卷 402-409页

作者： HE XiuXia1,2,JIN ChongWei1, LI GuiXin3, YOU GuangYi4, ZHOU XuePing3 & ZHENG ShaoJian4 1 Key Laboratory for Environmental and Ecosystem Health of the Ministry of Education, college of Environmental and Resource Science, Zhejiang university, Hangzhou 310029, china 2 college of Life Science, changchun university of Science and Technology, changchun 130022, china 3 Institute of Biotechnology, Zhejiang university, Hangzhou 310029, china 4 State Key Laboratory of Plant Physiology and Biochemistry, college of Life Science, Zhejiang university, Hangzhou 310058, china 1. Key Laboratory for Environmental and Ecosystem Health of the Ministry of Education College of Environmental and Resource Science Zhejiang University Hangzhou 310029 China 2. college of Life Science Changchun University of Science and Technology Changchun 130022 China 3. Institute of Biotechnology Zhejiang University Hangzhou 310029 China 4. State Key Laboratory of Plant Physiology and Biochemistry College of Life Science Zhejiang University Hangzhou 310058 China

Virus-induced gene silencing (VIGS) is potentially an attractive reverse-genetics tool for studies of plant gene function, but whether it is effective in silencing mineral nutritional-related genes in roots has not been demonstrated. Here we report on an efficient VIGS system that functions in tomato roots using a modified viral satellite DNA (DNAmβ) associated with Tomato yellow leaf curl china virus (TYLCCNV). A cDNA fragment of the ferric chelate reductase gene (FRO1) from tomato was inserted into the DNAmβ vector. Tomato roots agro-inoculated with DNAmβ carrying both a fragment of FRO1 and TYLCCNV used as a helper virus exhibited a significant reduction at the FRO1 mRNA level. As a consequence, ferric chelate reductase activity, as determined by visualization of the pink FeBPDS3 complex was significantly decreased. Our results clearly demonstrated that VIGS system can be employed to investigate gene function associated with plant nutrient uptake in roots.

关键词： virus-induced gene silencing roots ferric chelate reductase

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Polyspectral Analysis of Two-dimensional Mixed Processes and Coupled Harmonics

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The Journal of china Universities of Posts and Telecommunications 2002年第3期9卷 1-6页

作者： WANG Fei, WANG Shu xun, DOU Hui jing (college of Communication engineering, jilin university, changchun 130025, P.R.china) college of Communication engineering Jilin University Changchun 130025 P.R.China

In this paper, two-dimensional scaled polyperiodograms are introduced toanalyze two-dimensional mixed processes and harmonics after undergoing quadratic *** of the mixed processes and frequencies of harmonics after undergoing quadratictransformation can be extracted successfully by the two-dimensional second-order scaledpolyperiodograms and the third-order scaled polyperiodograms, respectively. Theory and algorithm areillustrated by simulation examples.

关键词： two-dimensional cyclostationary multiplicative noise

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Study of Laser Lap Welding of SUS301L Austenitic Stainless Steel Using Optimal Design Method

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稀有金属材料与工程 2011年第S4期40卷 63-67页

作者： Liu Jia,Shi Yan,Zhang Hong School of Electromechanical engineering,changchun university of Science and Technology,changchun 130022,china changchun Univ Sci & Technol Sch Electromech Engn Changchun 130022 Peoples R China

This paper presents an experimental design approach to process parameter optimization for the laser lap welding of SUS301L austenitic stainless steels using Nd:YAG laser in order to reduce the welding deformations of the back of the welding seams while ensuring mechanical properties of welding *** determine the optimal laser-welding parameters,a set of mathematical models were developed relating welding parameters to each of the weld *** were validated both statistically and *** order to reduce experimental error and the number of specimens,the part of orthogonal experiments were used in this *** quality criteria set for the weld to determine optimal parameters were the maximization of weld width and the minimization of weld *** power,welding speed,the laser irradiation angle,the focused distance and shield gas of 3.5kW,7.0m/min,70°,0mm and N2 with the flow of 30L/min,respectively,with a fiber diameter of 600μm were identified as the optimal set of process parameters.

关键词： laser lap welding sus301l austenitic stainless steel welding deformation orthogonal experiments

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