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Journal of university of science and technology Beijing 2001年第1期8卷 15-19页

作者： Jian Zhang Metallurgy school, university of science and {3. Beijing, Beijing 100083. China Univ Sci & Technol Beijing Met Sch Beijing 100083 Peoples R China

According to the mass action law and the coexistence theory of metallic melts, the mass action concentrations of Cu-Mg, Bi-Tl and Ni-Al melts involving compound formation have been calculated. The calculated results show that, except the ultimate case of pure element, when two elements are present in the melts, all structural units (atoms and molecules) without exception will be present in the melts, i.e., their concentrations may change from great to small, but they will not vanish into nothing, and only under such conditions, the calculated results both agree with practice and obey the law of mass action. In view of that over considerable wide composition range, the activities of both elements of the three solid binary alloys mentioned above have been measured, this seems in contradiction with the present relevant phase diagrams, in which the structural units are determined by composition range, so the latter needs further investigation and consideration.

关键词： activity phase diagram the mass action law the coexistence theory

Bionic Design and Finite Element Analysis of Elbow in Ice Transportation Cooling System

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Journal of Bionic Engineering 2010年第3期7卷 301-306页

作者： Dejun Miao~(1,2), Xiuhua Sui~3. Linjing Xiao~3.1. Key Laboratory of Mine Hazard Prevention and Control (Ministry of Education, China), Shandong university of science and technology, Qingdao 266510, P. R. China 2. {3. of Architecture, Tsinghua university, Beijing 100084, P. R. China 3. College of Mechanical and Electronic Engineering, Shandong university of science and technology, Qingdao 266510, P. R. China [a] Key Laboratory of Mine Hazard Prevention Control (Ministry of Education China) Shandong University of Science technology Qingdao 266510 P. R. China [b] School of Architecture Tsinghua University Beijing 100084 P. R. China [c] College of Mechanical Electronic Engineering Shandong University of Science technology Qingdao 266510 P. R. China

With the increase in mining depth, mine heat harm has appeared to be more prominent. The mine heat harm could be resolvedor reduced by ice refrigeration. Thus, ice transportation through pipeline becomes a critical problem; typically flowresistance occurs in the elbow. In the present study, according to the analysis of the surface morphology of fish scale, abiomimetic functional surface structure for the interior wall of elbow is designed. Based on the theory of liquid-solid two phaseflow, a CFD numerical simulation of ice-water mixture flowing through the elbow is carried out using finite element *** experiments of pressure drop and flow resistance for both bionic and common elbows are conducted to test theeffect of the bionic elbow on flow resistance reduction. It is found that with the increase in the ice mass fraction in the ice-watermixture, the effect of bionic elbow on resistance reduction becomes more obvious.

关键词： bionic elbow two phase flow ice transportation flow resistance reduction pressure loss

Characteristics of fMRI BOLD signal and its neurophysiological mechanism

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Progress in Natural science:Materials International 2007年第6期17卷 630-638页

作者： Zhao Xiaohu1,2, Wu Yigen3.and Guo Shengli3.1. College of Life sciences, Zhejiang university, Hangzhou 3.0058, China 2. Imaging Department of Tongji Hospital of Tongji university, {3. 200065, China 3. College of Mathematics and Physics, Nanjing university of Information science and technology, Nanjing 210044, China) College of Life sciences Zhejiang University Hangzhou 310058 China Imaging Department Tongji Hospital Tongji University Shanghai 200065 China College of Mathematics and Physics Nanjing University of Information Science and Technology Nanjing 210044 China

The functional magnetic resonance imaging (fMRI) based on blood oxygen level dependent (BOLD) contrast has emerged as one of the most potent noninvasive tools for mapping brain function and has been widely used to explore physiological, pathological changes and mental activity in the brain. Exploring the nature and property of BOLD signal has recently attracted more attentions. Despite that great progress has been made in investigation of the characteristics and neurophysiological basis, the exact nature of BOLD signal remains unclear. In this paper we discuss the characteristics of BOLD signals, the nonlinear BOLD response to external stimuli and the relation between BOLD signals and neural electrophysiological recordings. Furthermore, we develop our new opinions regarding nonlinear BOLD response and make some perspectives on future study.

关键词： functional magnetic resonance imaging blood oxygen level dependent nonlinear response neural electrophysiological activity.

Tissue P systems with parallel rules on channels

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Progress in Natural science:Materials International 2007年第4期17卷 486-491页

作者： Xu Xian (Department of Computer science and technology, shanghai Jiao Tong {3., shanghai 2.02.0, China) [a]Department of Computer science and technology Shanghai Jiao Tong University Shanghai China

A new variant of P systems as an improvement of the original design is introduced. The P systems here allow parallelism in rules application on synapses (or links, channels), rendering the systems more efficient. We describe the execution mechanism of our P systems, make analysis on its computation power, and illustrate the running by an example.

关键词： tissue P systems parallel rules.

Annealing Texture Evolution of Ti-IF Steel during Batch Annealing

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 175-179页

作者： Jing Shi Xianjin Wang(Material science and Engineering school, university of science and technology Beijing, Beijing 100083. China) Material science and Engineering school University of Science and Technology Beijing Beijing 100083 China

Texture development and recrystallization behavior of Ti-IF steel during Batch Annealing (BA) were investigared with X-ray diffraction and EBSP in lab, and the results were compared with research work on continu ous annealing (CA) with rapid heating rate. The basic tendencies are similar that eary nucleation takes place in ND fibers, RD fibers are consumed at the end of recrystallization, and ND texture dominates over annealing texture. However, the detailed texture transformation during batch annealing is different and somewhat more compicated than tha in rapid-heating process. Moreover, misorientation plays an important role in texture transformation of BA In addition, the results of EBSP are consistent with that of ODF well.

关键词： Ti-IF steel texture batch annealing X-ray diffraction EBSP

Calculating Model of Mass Action Concentrations for Mn-C Melts and Optimization of Thermodynamic Parameters

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International Journal of Minerals,Metallurgy and Materials 1998年第4期12卷 208-211页

作者： Jian Zhang(Metallurgy school, university of science and {3. Beijing, Beijing 100083. China) Metallurgy school University of Science and Technology Beijing Beijing 100083 China

Based on the phase diagram, the coexistence theory of the metallic melt structure involving compoundformation and the regularity of melts containing saturated phase, a calculating model of mass action concentrationsfor Mn-C melts was formulated. According to the activities (or activity coefficients AM. and γc.), obtained by theUnified Interaction Parameter Model (UIPM), the thermodynamic parameters G and G at higher temperatures (1628～1873.K) were optimized by the repeated try and error method. It is testified that G G(873.1273.K) and G (298～1623.K), obtained at lower temperatures, can also be used at the above-mentionedhigher temperatures. The calculated N. and N agree well with ac. and ac obtained by UIPM. This result showsthat the deduced model can reflect the structural reality of Mn-C melts.

关键词： Mn-C melts activity coexistence theory mass action concentration

Calculating Models of Mass Action Concentrations for Ni-Mn and Co-Mn Melts and Optimization of Their Thermodynamic Parameters

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 246-250页

作者： Jian Zhang (Metallurgy school, university of science and {3. Beijing, Beijing 100083. China) Metallurgy school University of Science and Technology Beijing Beijing 100083 China

According to phase diagrams, measured activities as well as the coexistence theory of motallic melts structure involving compound formation, the calculating models of mass action concentrations for Ni-Mn and Co-Mn melts are formulated and their thermodynamic parameters are optimized. As a result, the calculated mass action concentrations agree well with the corresponding measured activities, showing that these models can reflect the structural characteristics of both Ni-Mn and Co-Mn melts.

关键词： activity metallic melts coexistence theory mass action concentration

On edge dislocation in a multilayered laminate

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Theoretical & Applied Mechanics Letters 2011年第2期1卷 25-28页

作者： Xu Wang~(a) school of Mechanical and Power Engineering,east China university of {3. and technology,shanghai 20023., China school of Mechanical and Power Engineering East China University of Science and Technology Shanghai 200237 China

We investigate the elastic field induced by an edge dislocation in a multilayered laminated composite composed of(N—2)thin bonded elastic layers sandwiched between two semi-infinite elastic media.A simple closed-form solution is obtained when all the phases have equal shear modulus but different Poisson's ratios,and when the dislocation is located in the upper semi-infinite *** image force acting on the dislocation due to its interaction with the multilayered structure is also derived. Several specific examples are discussed in detail to illustrate the mobility of the edge dislocation. Some interesting behaviors of the dislocation are *** results indicate that it is possible to find at most(N—2)equilibrium positions for the edge dislocation in an N-phase composite structure.

关键词： laminated composite edge dislocation image force equilibrium position

Mechanical and Experimental Study of Sprinkling Water Cooling System on Roof of shanghai Expo Theme Pavilion

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湖南大学学报（自然科学版） 2009年第S1期36卷 156-159页

作者： ZHAO Hui-zhong1,HUANG Chen1,LI Wei-xiang2,SHI Jin-yue2,TAO Si-yuan1,WANG Qian1,WANG Yu-qing1,ZHANG Min3.1.College of Urban Construction and Environment Engineering,university of shanghai for science and {3.,shanghai 200093.China 2.Architectural Design & Research Institute of Tongji university,shanghai 200092,China 3.College of Food science {3.,shanghai Ocean university,shanghai 2013.6,China) College of Urban Construction and Environment Engineering University of Shanghai for Science and Technology Shanghai 200093 China Architectural Design and Research Institute Tongji University Shanghai 200092 China College of Food science technology Shanghai Ocean University Shanghai 201306 China

Based on the similarity theory,a scale effect model of the spraying water cooling system of shanghai expo Theme Pavilion's roof was set *** to the typical weather conditions in shanghai city,different models were analyzed on solar radiation,and different heat transfer amount was *** the following conclusions could be made:At the sunny day of summer in shanghai,the temperature of inner roof with sprinkling system descended about 3.℃,and the air conditioning load of the whole Theme Pavilion descend more than 3.0 kW.

关键词： shanghai expo large space atrium solar radiation roof sprinkling system similarity theory prototype

Distribution of Nb atom in the TiAl+Nb system

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Rare Metals 2001年第1期20卷 5-12页

作者： Xiaodong Ni, Xidong Hui, Guoliang Chen (Applied science school, university of science and technology Beijing, Beijing 100083. China State Key Laboratory for Advanced Metals and Materials, university of science and technology Beijing, China) Appl. Sci. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Based on MEAM (the modified embedded atom method) potential and an average atom model similar to B-W (Bragg-Williams) method, the distribution of Nb atoms in TiAl+Nb compounds with various composition was calculated. The calculation results showed that Nb atoms prefer to occupy the Ti sublattice of L10 structure for all compounds in question. With increasing atomic fraction of Nb and Al, Nb atoms exhibited a trend of ordered distribution on the Ti sublattice and result in a new L10 derivative superlattice structure.

关键词： Computer simulation Intermetallics Superlattices Ternary systems