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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 university, shanghai 200240, china.) school of Environmental science and Engineering Shanghai Jiaotong University 上海 200240

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 S3307D, 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 S3307D. 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

Study on Activated Bentonite Applied to tert-Butylation of Toluene

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china Petroleum Processing & Petrochemical technology 2011年第1期13卷 38-44页

作者： Chen Linbo Shi Li (Department of Petroleum Processing,east china university of science and technology,shanghai 2.02.7) Department of Petroleum Processing East China University of Science and Technology Shanghai 200237 China

tert-Butylation of toluene with tert-butanol used as the alkylating agent was investigated over the activated bentonite and HY zeolite used as the *** influences of various butylation reaction parameters,including the toluene/tert-butanol ratio,the reaction temperature,and the space velocity were *** optimal results were obtained at a reaction temperature of 180 ℃,a space velocity of 4 h-1,and a mole ratio of toluene to tert-butanol equating to *** structure and acidic properties of catalyst were characterized by the BET method and the Fourier transform infrared (FTIR) *** with the HY zeolite,the activated bentonite possessed high activity for toluene conversion and high para-selectivity because it had larger pore diameter,smaller micropore surface area and higher ratio of total Lewis acids to total Br nsted acids.

关键词： t-butylation activated bentonite p-tert-butyltoluene pore diameter Lewis acid

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 university, shanghai 201800, china) Dengren JIN (school of Materials science and Engineering, shanghai Jiaotong university, shanghai 200030, 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

Early Age Compressive Strength of Pastes by Electrical Resistivity Method and Maturity Method

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Journal of Wuhan university of technology(Materials science) 2011年第5期26卷 983-989页

作者：肖莲珍 school of Materials science and Engineering Wuhan Institute of Technology

The compressive strength development of Portland cement pastes was investigated by the electrical resistivity method and the maturity *** experiments were carried out on the cement pastes with different water-cement ratios at different curing *** results show that the application of the maturity method has limitation to obtain the *** is found that both of the compressive strength and the electrical resistivity follow hyperbolic trend for all the *** hyperbolic equation of each mix is obtained to estimate the ultimate resistivity value which can probably be *** relationship between electrical resistivity and compressive strength of the cement pastes is established based on the test results and interpreted by the empirical Archie equation and a strength-porosity *** relationship between the electrical resistivity after temperature correction and the compressive strength was linear and independent of curing temperature and water-cement ratio.

关键词： electrical resistivity cement hydration compressive strength maturity method

Real estate appraisal system based on GIS and BP neural network

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中国有色金属学会会刊：英文版 2011年第S3期21卷 626-630页

作者： LIU Xiao-sheng1, DENG Zhe1, WANG Ting-li2 1. school of Architecture and Survey Engineering, Jiangxi university of science and technology, Ganzhou 341000, china 2. school of Applied science, Jiangxi university of science and technology, Ganzhou 341000, china school of Architecture and Survey Engineering Jiangxi University of Science and Technology Ganzhou 341000 China school of Applied science Jiangxi University of Science and Technology Ganzhou 341000 China

For the inefficiency and inaccuracy of appraisal method of traditional estate appraisal theory, the real estate appraisal system based on GIS and BP neural network was established. The structure of the system was designed which includes appraisal model, trade case, GIS database and query analysis module. With the help of the L-M algorithm in MATLAB software, BP neural network was improved and the trade cases were trained, then the BP neural network which has already been trained was tested. At the same time, the BP neural and GIS were put together to construct the hedonic price estimate model. The C# and ArcGIS9.3 were used to achieve the system in VS2008. City basic geographic data and real estate related information were used as the basic data in practice. The results show that the functions of querying, adding and editing the spatial data and attribute data are achieved and also the efficiency and accuracy of real estate are improved, so that the new method of real estate is provided by the system.

关键词： BP neural network GIS hedonic price real estate appraisal

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 science and technology,shanghai 2.02.7, 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

Fusion Protein of Interleukin 4 and Diphtherial Toxin with High Cytotoxicity to Cancer Cells

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Acta Biochimica et Biophysica Sinica 2004年第6期36卷 437-442页

作者： Yu-Jian ZHANG, Xiao-BoHU, Su-Xia LI1, Li-Ping TIAN, Sheng-Li YANG, and Yi GONG* Research Center of Biotechnology, shanghai Institutes for Biological sciences,Chinese Academy of sciences, Graduate school of the Chinese Academy of sciences, shanghai 200233, china State Key Laboratory of Bioreactor Engineering, east china university of science and technology, shanghai 2.02.7, china Research Center of Biotechnology Shanghai Institutes for Biological SciencesChinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200233 China State Key Laboratory of Bioreactor Engineering East China University of Science and TechnologyShanghai 200237 China

Receptor of human interleukin 4 (hIL4R) has been found to be present on many types of cancer, so it may be a good target for cancer therapy. Here, fusion toxin gene DT4H has been constructed by fusing DNA sequence encoding the first 389 amino acids of diphtherial toxin (DT), which can not bind its own receptor, to human interleukin 4 (hIL4) gene. In order to improve the affinity of fusion toxin for hIL4R, a circularly permuted form of hIL4 (cpIL4) was used. The fusion gene was expressed in Escherichia coli where the fusion toxin DT4H was highly expressed. Purified DT4H was very cytotoxic to cancer cell line U251 cells, and moderate cytotoxic to HepG2 and MCF-7 cells. SGC-7901 cells were insensitive to it. The cytotoxic action of DT4H was specific because it was blocked by excess hIL4. These results suggest that DT4H may be a useful agent in the treatment of certain malignancies.

关键词： fusion toxin diphtherial toxin cancer therapy interleukin 4 IL-4 receptor

A new approximating method for Holstein model

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science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 44-48页

作者： REN XueZao 1 , LIAO Xu 1 , LI Lei 1 & WANG KeLin 2 1 school of science, Southwest university of science and technology, Mian Yang 621010, china 2 Department of Modern Physics, university of science and technology of china, Hefei 230026, china school of science Southwest University of Science and Technology Mian Yang China Department of Modern Physics University of Science and Technology of China Hefei China

A new approach-the method of coherent state orthogonal expansion is developed for one-dimensional Holstein model. In zeroth order approximation, the formula of ground state energy is deduced analytically and the solutions in strong- and weak-coupling limits are obtained correctly. When the trial wave-function of ground state is expanded to the second order, the obtained ground state energy agrees quite well with that calculated by numerical method in all coupling regimes. The present approach can be easily generalized to the situations of higher dimensions and more electrons.

关键词： coherent-state orthogonal expansion polaron simulated annealing method

Phase transition in the Zr_(60)Al_(15)Ni_(25) bulk metallic glass subjected to rolling at room temperature

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science china(Technological sciences) 2006年第6期49卷 655-662页

作者： YAN Zhijie1, 2, LI Jinfu1, ZHOU Yaohe1 & WU Yanqing3 1. State Key Laboratory of Metal Matrix Composites, school of Materials science and Engineering, shanghai Jiao Tong university, shanghai 200030, china 2. school of Materials science and Engineering, Taiyuan university of science and technology, Taiyuan 030024, china 3. school of Environmental science and Engineering, shanghai Jiao Tong university, shanghai 200030, china State Key Laboratory of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai China school of Materials science and Engineering Taiyuan University of Science and Technology Taiyuan China school of Environmental science and Engineering Shanghai Jiao Tong University Shanghai China

The microstructure evolution of the Zr60Al15Ni25 metallic glass during rolling at room temperature is investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC); high-resolution transmission electron microscopy (HREM). The results show that the values of full width at half maximum (FWHM) of the XRD patterns; exothermic enthalpy ΔH of DSC plots do not monotonically change with the variation of deformation degrees . As is not large than 20%, the values of FWHM; ΔH are lower than that of the as-cast state. When reaches 30%, the values of FWHM; ΔH become larger than that of the as-cast state, while their values begin to decrease again as reaches about 85%. These results indicate that the reversible transitions between ordered; disordered atomic configurations occur during rolling, which is further verified by the HREM images. The reversible phase transition can be explained by the competition between the diffusion controlled reordering; shear-induced disordering during rolling.

关键词： metallic glasses, plastic deformation, phase transformations, shear bands.