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A Resistivity Gradient Piezoelectric FGM Actuator

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Journal of Materials science & technology 2000年第4期16卷 383-386页

作者： S. U.Adikary and Zhongyan MENG (school of Materials science and Engineering, shanghai {3., shanghai 201800, china) Dengren JIN (school of Materials science and Engineering, shanghai Jiaotong {3., shanghai 20003., china) school of Materials science and Engineering Shanghai University Shanghai 201800 China school of Materials science and Engineering Shanghai Jiaotong University Shanghai 200030 China

A resistivity gradient actuator based on lead zirconate titanate ceramics was successfully developed and the bending deflections up to 140 μm were obtained. The actuator material was a matrix of PZT ceramic into which smooth gradient of piezoelectric activity was introduced. The application of an electric field then causes the actuator to bend due to differential strains induced by the piezoelectric effect. The resistivity gradient of the actuator was achieved by doping PZT with suitable donor and acceptor dopants. PZT powder was modified and synthesized by using two stage powder fabrication method. The actuator was fabricated by uniaxial pressing followedby isostatic pressing with two layers of different resistivities.

关键词： PZT FGM

Sorption of a triazol derivative by soils: importance of surface acidity

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Journal of Environmental sciences 2003年第3期15卷 383-387页

作者： WU De-yi (school of Environmental science and Engineering, shanghai Jiaotong {3., shanghai 200240, china.) school of Environmental science and Engineering Shanghai Jiaotong University Shanghai 200240 China

The sorption of a triazol derivative, 1-(4-chlorophenyl)- 4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)penten-3.ol with a common name of S3.07D, on fifteen soils and three H_2O_2-treated soils was investigated. The sorption isotherm for each untreated and treated soil was non-linear, and was best fitted to Freundlich sorption equation. Soils containing high amount of clay content or organic matter or both sorbed much higher amounts of the chemical than soils that had low contents of these soil constituents. H_2O_2-treated soils showed considerable sorptive affinity for S3.07D. It was concluded that both organic matter and mineral fraction in natural soils contributed to the sorption of the basic compound. Sorption by the H_2O_2 treated soils increased as suspension pH decreased, but all suspension pHs exceeded the pKa of the compound by more than two units. This implies that organic base protonation can occur on surfaces of soil components, and surface acidity (exchangeable acidity ) is important in sorption process of the organic base rather than suspension pH.

关键词： sorption organic base soil surface acidity

Algorithm for Computation of Unstructured Real Stability Radius and Its Applications

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International Journal of Minerals,Metallurgy and Materials 1998年第4期12卷 245-250页

作者： Xiaodan Zhang Lequan Min(Applied science school, university of science and technology Beijing, Beijing 100083. china) Applied science school University of Science and Technology Beijing Beijing 100083 China

An algorithm for the computation of the unstructured real stability radius of high dimensional linearsystem is presented. Using the accurate formula of the real stability radius of 2-dimensional system linear systemchecks the algorithm. The result shows that the algorithm is reliable and efficient. As applications, the unstructuredreal stability radii of 2-dimensional Chua's circuit and 3.dimensional piecewise-linear system are calculated, thedynamical orbits of the corresponding perturbed systems are simulated.

关键词： lincar systems stability robustness parameter perturbation computational methods

Mechanism Analysis of Helical and Twisted Reinforcement

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Journal of Wuhan university of technology(Materials science) 2008年第1期23卷 24-28页

作者：张钧林 ZHOU Bo school of Materials science and Engineering Tongji University Shanghai 200092 China

Although helical and twisted reinforcement has been used to reinforce concrete for more than two decades, its rationale still remains unclear. With a brief review of current researches on the helical and twisted reinforcement properties, this paper describes some new phenomenon of the helical and twisted reinforcement in concrete and other matrix by experimental studies, and then discusses on mechanism of helical effect of strengthening. This paper also discusses the mechanism of accessional helical effect of strengthening and its significance in industrial practice. Extensive tests indicate that twisting is the most effective way to improve reinforcement mechanical properties. The main results are：（1） They can greatly enhance bond anchorage in base material. In some pull-out tests, the pull-out resistance increases with reinforcement slip within the specimens, which results not only in a higher pull-out load but also a larger slip up to 70%-80% of reinforcement embedded length. （2） Concrete reinforced by twisted bars demonstrates certain ductility at failure. （3. The bond strength depends on the pitch space directly. （4） The twisted effect on material strengthening is from a three-dimensional interlocking force which is formed from material untwisting when they were pulled out from base specimens.

关键词： twisted reinforcing materials helical and twisted effect structural ductility

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 200240, 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.

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

A Back Look on the Binary Phase Diagrams of Metals from the Mass Action Law and the Coexistence Theory of Metallic Melts

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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

Unified solutions for stresses and displacements around circular tunnels using the Unified Strength Theory

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science china(Technological sciences) 2010年第6期53卷 1694-1699页

作者： ZHANG ChangGuang1,WANG JiangFeng2 & ZHAO JunHai3.1 Department of Geotechnical Engineering,tongji university,shanghai {3.,china 2 North china Institute of Water Conservancy and Hydroelectric Power,Zhengzhou 450011,china 3.school of Civil Engineering,Chang’an university,Xi’an 710061,china 1. Department of Geotechnical Engineering Tongji University Shanghai 200092 China2. North China Institute of Water Conservancy and Hydroelectric Power Zhengzhou 450011 China3. School of Civil Engineering Chang’an University Xi’an 710061 China

The unified solutions are presented for stresses and displacements around a circular tunnel subjected to a hydrostatic stress *** rock mass is assumed to be elastic-brittle-plastic and governed by the Unified Strength *** displacements are obtained accounting for three different definitions for elastic strains and different Young's modulus in the plastic *** unified solutions obtained in this paper are especially versatile in reflecting the intermediate principal stress effect to different extents for different *** conventional solutions,based on the Mohr-Coulomb failure criterion and the Generalized Twin Shear Stress yield criterion,are special cases of the present unified *** new unified solutions can compare with those computed by the latest generalized Hoek-Brown failure *** results obtained demonstrate the importance of the intermediate principal stress influence for the stresses and displacements *** effects of different definitions for elastic strains and different Young's modulus in the plastic zone on the displacements are significant.

关键词： Unified Strength Theory intermediate principal stress different definitions for elastic strains different Young’s modulus

Development and Application of High Performance X80 Line Pipe for the 2^(nd) West-East Gas Pipeline

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Journal of Iron and Steel Research International 2011年第S1期18卷 39-48页

作者： LI He-lin 1 , HUO Chun-yong 1 , JI Ling-kang 1, 2 , LI Yang 1, 3.(1. CNPC Tubular Goods Research Institute, Xi’an 710065, china 2. . school of Material science and Engineering, Xi’an Jiaotong {3., Xi’an 710049, china 3. school of Material science and Engineering, {3. of science and technology Beijing, Beijing 100083. china) CNPC Tubular Goods Res Inst Xian 710065 Peoples R China Xi An Jiao Tong Univ Sch Mat Sci & Engn Xian 710049 Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

It is the development tendency of gas pipeline to improve strength of line pipe and transmission pressure, which is an important symbol of the progress of gas pipeline technology. The 2nd West-East Gas Pipeline (the 2 nd WEGP) is the largest-scale X80 high pressure gas pipeline project in the world. Through the joint development project by Pipeline Company, research institute, and steel company, a series of achievements of technology have been obtained, which makes it possible to apply pressure of 12 MPa and X80 LSAW and HSAW pipe for the 2 nd WEGP. Specifications of X80 steel and pipe have been issued based on API 5L. High performance X80 steel and pipe have been developed and meets the Specification. General design conception of applying HSAW pipe and LSAW pipe on gas transmission trunk line with large diameter and high pressure has been established. Failure control of the 2 nd WEGP has been carried out to avoid failure and reduce the lost which based on analysis of pipeline failure mode. In this paper, research and development of high performance X80 welded pipe, establishment of technical route of joint application of HSAW and LSAW steel pipe and key technology of failure control are emphatically discussed.

关键词： 2 nd WEGP acicular ferrite failure control arrest toughness strain-based design