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Science China Chemistry 2009年第7期52卷 916-923页

作者： LIU Yi1,2. CHEN Yun1, ZENG YuPing2.& WANG ShiLong3.1 Department of Chemistry and Chemical engineering, Zaozhuang {3., Zaozhuang 2.7160, China 2.{2. Institute of Ceramics, Chinese Academy of Sciences, {2. 2.0050, China 3.school of Life Science and Technology, tongji university, shanghai 200092, China 1. Department of Chemistry and Chemical engineering Zaozhuang University Zaozhuang 277160 China 2. shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China 3. school of Life Science and Technology Tongji University Shanghai 200092 China

A series of nanostructured iron compounds including cubic Fe3.4 and orthorhombic FeOOH were synthesized via a facile low temperature (in the range of 60-100℃) solution method. In the whole process, the interaction between FeCl2.4H2. and methenamine (C6H12.4) was carried out through a reflux device under different reaction conditions such as temperature, solvent, and duration. The samples were detected by XRD, TEM, SAED, physical property measurement system, and Mssbauer spectroscopy, separately. The experiments showed that magnetic mixture nanoparticles had flake and rod morphologies, and cubic Fe3.4 took on grain nanostructure. Magnetism measurements indicated that the saturated magnetization of the as-obtained magnetic mixture was lower than that of the cubic magnetite. Mssbauer spectroscopy testified the sample consisting of cubic magnetite rather than γ-Fe2.3. In addition, a possible growth mechanism of cubic magnetic nanoparticles under different conditions was discussed.

关键词： magnetic nanoparticles cubic Fe3.4 oxidation-coprecipitation method reflux magnetic properties at room temperature Mssbauer spectrum

Phase transition in the Zr_(60)Al_(15)Ni_(2.) 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, {2. Jiao Tong {3., {2. 2.003., China 2. school of Materials Science and engineering, Taiyuan {3. of Science and Technology, Taiyuan 03.02., China 3. school of Environmental Science and engineering, {2. Jiao Tong {3., {2. 2.003., China State Key Laboratory of Metal Matrix Composites School of Materials Science engineering Shanghai Jiao Tong University Shanghai 200030 China school of Materials Science engineering Taiyuan University of Science Technology Taiyuan 030024 China school of Environmental Science engineering Shanghai Jiao Tong University Shanghai 200030 China

The microstructure evolution of the Zr60Al15Ni2. 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 2.%, the values of FWHM; ΔH are lower than that of the as-cast state. When reaches 3.%, 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.

Discrete Element Modeling of Asphalt Concrete Cracking Using a User-def ined Three-dimensional Micromechanical Approach

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Journal of Wuhan university of Technology(Materials Science) 2011年第6期26卷 1215-1221页

作者：陈俊 College of Civil and transportation engineering Hohai University

We established a user-defined micromechanical model using discrete element method （DEM） to investigate the cracking behavior of asphalt concrete （AC）. Using the ＂Fish＂ language provided in the particle flow code in 3.Demensions （PFC3.）, the air voids and mastics in asphalt concrete were realistically built as two distinct phases. With the irregular shape of individual aggregate particles modeled using a clump of spheres of different sizes, the three-dimensional （3.） discrete element model was able to account for aggregate gradation and fraction. Laboratory uniaxial complex modulus test and indirect tensile strength test were performed to obtain input material parameters for the numerical simulation. A set of the indirect tensile test were simulated to study the cracking behavior of AC at two levels of temperature, i e, -10 ℃ and 15 ℃. The predicted results of the numerical simulation were compared with laboratory experimental measurements. Results show that the 3. DEM model is able to predict accurately the fracture pattern of different asphalt mixtures. Based on the DEM model, the effects of air void content and aggregate volumetric fraction on the cracking behavior of asphalt concrete were evaluated.

关键词： discrete element method asphalt concrete cracking behavior three-dimensional simulation micromechanics

Conversion of organic carbon in the decomposable organic wastes in anaerobic lysimeters under different temperatures

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Journal of Environmental Sciences 2003年第3期15卷 315-322页

作者： ZHAO You-cai, WANG Luo-chun (National Laboratory of Pollution Control and Resource Reuse, school of Environmental engineering, {2., {3., China.) National Laboratory of Pollution Control and Resource Reuse School of Environmental Engineering Tongji University Shanghai 200092 Chin

The quantitative fractions of conversion of organic carbon in the decomposable organic wastes with initial moisture of 70% sorted from municipal solid wastes(MSW) in lysimeters into biogas, leachate and solid residue were characterized, under temperatures of 2., 3. and 41℃, respectively, and circulation of leachate generated within the lysimeters. It is found that 2.% of organic carbon in the wastes are conversed into gases, 0.8% into leachate, and the other 72. remained in the decomposable solid residues, after 180 days' degradation at 41℃. Higher temperature will lead to more rapid degradation and result to higher conversion of the organic carbon to biogas and lower to both solid residues and leachate, while the pollutant concentrations in leachate will be lower at a higher temperature and the values of COD are quite consistent with TOC.

关键词： refuse organic wastes lysimeters organic carbon conversion

Excavation and characterization of refuse in closed landfill

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Journal of Environmental Sciences 2002年第3期14卷 303-308页

作者： ZHAO You cai (The State Key Laboratory of Pollution Control and Resource Reuse, school of Environmental Science and engineering, {2., {3., China. ) State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and Engineering Tongji University Shanghai 200092 China

Refuse in landfills becomes stabilized as organic matter in refuse degrades and soluble inorganic substances dissolve during their long term stabilization process. In this paper, this process is also referred to as mineralization process and the resultant stabilized refuse referred to as aged refuse. Aged refuse contains a wide spectrum and huge quantity of microorganisms with strong decomposition capability for refractory organic matter present in some wastewater such as leachate. In this study, aged refuse excavated from 2.to 10 years old closed landfill compartments in shanghai Refuse Landfill is characterized in terms of particulate distribution by screening, total nitrogen, total phosphorus, biodegradable matter. The approaches for redevelopment of both land and aged refuse in the stabilized landfills are proposed.

关键词： landfill refuse mineralization

Effect of Polypropylene Fibers on the Long-term Tensile Strength of Concrete

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Journal of Wuhan university of Technology(Materials Science) 2007年第1期22卷 52-55页

作者：姚武 school of Materials Science and engineering Tongji University

The influence of low volume fraction of polypropylene（PP） fibers on the tensile properties of normal and high strength concretes was studied. The experimental results indicate that the addition of PP fibers in concrete leads to a reduction in tensile strength during the age of 2. d. Whereas, after 2. days, there is a notable effect in tensile strength due to PP fibers restraining the formation and growth of microcracks in concrete, which improves the continuity and integrality of concrete structure, Thus, a low volume fraction of PP fibers is beneficial to enhancing the long-term tensile strength of concrete materials and improving the durability of concrete structures.

关键词： polypropylene fiber concrete tensile strength microcrack

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,{2.,China 2.North China Institute of Water Conservancy and Hydroelectric Power,Zhengzhou 450011,China 3.{3. 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

Paleoceanographic evolution recorded in the northern South China Sea since 4 Ma

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Science China Earth Sciences 2005年第12期48卷 2166-2173页

作者： HUANG Baoqi1,2. JIAN Zhimin2.& WANG Pinxian2.1. {3. of Earth and Space Sciences, Peking university, Beijing 100871, China 2. Laboratory of Marine Geology, {2., {3., China 1. school of Earth and Space Sciences Peking University 100871 Beijing China 2. Laboratory of Marine Geology Tongji University 200092 Shanghai China

Upper water structure over the last 4 million years in the northern South China Sea (SCS) was reconstructed by sea surface temperature (SST) and primary productivity estimated by changes in the abundance of planktonic foraminifer, planktonic foraminifer transfer function, and the accumulation rate of benthic foraminifera. Results of SST and primary productivity show that SST gradually decreased since 4 Ma, but differential seasonal temperature and primary productivity increased in steps mainly at about 3.1, 2.7, 2.1, 1.6, 0.9 and 0.5 Ma. Comparison with tectonics and orbital variations indicates that phased rising of the Tibet since 3.6 Ma, closing of Panama and Indonesian seaways, and orbital changes were responsible for the changes of upper water structure in the SCS, respectively.

关键词： northern South China Sea, upper water structure, Late Pliocene, planktonic foraminifer, ODP 1146.

Chimney Effect Assessment of the Double-skin Facade

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湖南大学学报（自然科学版） 2009年第S1期36卷 146-150页

作者： QIU Zhong-zhu1,LI Peng2.CHOW Tin-tai3.REN Jian-xing1,WANG Wen-huan1(1.school of Energy & Environment engineering,{2. {3. of Electric Power,{2. 2.090,China 2.school of Mechanical engineering,tongji university,shanghai 200092,China 3.Division of Building Science & Technology,City {3. of Hong Kong,Hong Kong SAR,China) school of Energy and Environment engineering Shanghai University of Electric Power Shanghai 200090 China school of Mechanical engineering Tongji University Shanghai 200092 China Division of Building Science and Technology City University of Hong Kong Hong Kong Hong Kong

The mathematic model of heat transfer through ventilated double glazing was verified with the measured data,which were from a test chamber equipped with glass face temperature,solar radiation,ambient temperature,and wind speed measurement *** the model validation,the double-skin facade assessment was carried out through simulation with ESP-r software integrating thermal simulation and air low net work *** air flow situation in the air gap was analyzed on the basis of the hourly air velocity simulation data within typical winter week,summer week,spring week and autumn *** differences of chimney effect in different seasons were discussed,and the thermal loads resulted from the ventilated and unventilated double skin facade were presented.

关键词： chimney effect assessment double-skin facade

Recovery of molybdenum，phosphorus and arsenic from leaching solution ofmolybdenum residues by solvent extraction with primary amine and tributylphosphate

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Journal of Environmental Sciences 1995年第4期7卷 468-477页

作者： Zhao Youcai, Chen Shaowei, Xu Dimin(National Laboratory of Pollution Control and Reclamation, school of Environmental engineering , {2., {3.,China)Lin Ming(Institute of Applied Technology, {2., {3.,

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Ｒｅｃｏｖｅｒｙｏｆｍｏｌｙｂｄｅｎｕｍ，ｐｈｏｓｐｈｏｒｕｓａｎｄａｒｓｅｎｉｃｆｒｏｍｌｅａｃｈｉｎｇｓｏｌｕｔｉｏｎｏｆｍｏｌｙｂｄｅｎｕｍｒｅｓｉｄｕｅｓｂｙｓｏｌｖｅｎｔｅｘｔｒａｃｔｉｏｎｗｉｔｈｐｒｉｍａｒｙａｍｉｎｅａｎｄｔｒｉｂｕｔ...

关键词： molybdenum arsenic phosphorus solvent extraction molybdenum residues.