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science china(Technological sciences) 2010年第5期53卷 1285-1289页

作者： LI LanQiang1,DONG ShiGang1,WANG Wei2,HU RongGang1,DU RongGui1,LIN ChangJian1,ZHUO XiangDong1 & WANG Jia2 1 state Key laboratory of Physical Chemistry of solid Surfaces,department of Chemistry,College of Chemistry and Chemical engineering,Xiamen university,Xiamen 361005,china 2 College of Chemistry and Chemical engineering,Ocean university of china,Qingdao 266100,china 1. state Key laboratory of Physical Chemistry of solid Surfaces Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China2. College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China

An array electrode technique was developed as a novel electrochemical method for studying the interaction between macrocell and microcell in the early corrosion process of reinforcing steel in cement *** corrosion potential and galvanic current of macrocell corrosion of the reinforcing steel in cement mortar were imaged by the array electrode technique during the corrosion initiation and *** was certified that the corrosion macrocell current is closely related with the difference of corrosion potential between the anodic and cathodic *** corrosion macrocell and microcell always exist during the corrosion *** interaction of corrosion macrocell and corrosion microcell of steel in concrete was directly sensed by the array electrode for the first time,and was discussed in terms of corrosion electrochemistry.

关键词： reinforcing steel in concrete array electrode macrocell microcell

Anomalous magnetotransport in LaMn_(1-x)Te_xO_3

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science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 987-992页

作者： TAN GuoTai1,2, CHEN ZhengHao3 & ZHANG XiaoZhong4,5 1 Key laboratory of Beam Technology & materials Modification of the Ministry of Education, Institute of Low Energy Nuclear Physics, Beijing Normal university, Beijing 100875, china 2 Beijing Radiation Center, Beijing 100875, china 3 laboratory of Optical Physics, Institute of Physics, Chinese Academy of sciences, Beijing 100080, china 4 Key laboratory of Advanced materials of the Ministry of Education, department of materials science and engineering, Tsinghua university, Beijing 100084, china 5 Beijing national Center for Electron Microscopy, Tsinghua university, Beijing 100084, china 1. Key laboratory of Beam Technology & materials Modification of the Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China 2. Beijing Radiation Center Beijing 100875 China 3. laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China 4. Key laboratory of Advanced materials of the Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing 100084 China 5. Beijing national Center for Electron Microscopy Tsinghua University Beijing 100084 China

The LaMn1-xTexO3+δ (x=0.1, 0.2, 0.3) were synthesized using solid-state reaction method for the first time. X-ray photoemission spectrum (XPS) shows that in the samples the Te ions have a valence of Te4+, and Mn3+ ions are partly converted into Mn2+ and Mn4+ due to the excess oxygen and Te doping. The magnetotransport associated with Mn2+, Mn3+ and Mn4+ was investigated. The experimental results show that the samples are insulator at 0 T when the amount of Mn3+ is much larger or less than the sum of Mn2+ and Mn4+; by contrast, the samples display metal to insulator transition with increasing temperature when the amount of Mn3+ is close to the sum of Mn2+ and Mn4+. These anomalous magnetotransport behaviors were analyzed in the frame of the double-exchange (DE) mechanism.

关键词： colossal magnetoresistance La-Te-Mn-O magnetotransport

Size-controlled and large-scale synthesis of organic-soluble Ag nanocrystals in water and their formation mechanism

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Progress in Natural science:materials International 2011年第6期21卷 447-454页

作者： Yu-yuan SHI,Bin SUN,Zhe ZHOU,Yong-tao WU,Mei-fang ZHU state Key laboratory for Modification of Chemical Fibers and Polymer materials, College of material science and engineering,Donghua university,Shanghai 201620,china state Key laboratory for Modification of Chemical Fibers and Polymer materials College of Material Science and Engineering Donghua University Shanghai 201620 China

Organic-soluble Ag nanocrystals(NCs) with tunable sizes in the range from 5.4 to 22.1 nm were synthesized by a facile, reproducible and easily scaled up route using water as solvent in the presence of oleic acid and an *** synthetic Ag NCs exhibits excellent hydrophobicity and can be well re-dispersed in various non- or weak-polar *** tunable sizes of the Ag NCs were achieved by simply adjusting the initial precursor ***-scale synthesis of the Ag NCs was realized at a high AgNO3concentration(0.4 mol/L).As much as 16.2 g highly uniform organic-soluble Ag NCs with 5 nm average diameter can be readily synthesized at low cost in a single reaction only using 400 mL water as solvent,which is adaptable to the industrial scale *** structure of the obtained Ag NCs was investigated in detail by X-ray diffractometry,transmission electron microscopy,Fourier transform infrared and thermal gravimetric analysis *** results reveal that the surface of the organic-soluble Ag NCs is coated with the monolayer surfactants consisting of oleic acid and the *** addition,on the basis of the sufficient evidences,a proposed mechanism based on the "bilayer surfactant-controlled reaction" successfully demonstrates the formation of high quality organic-soluble Ag NCs in the aqueous solution.

关键词： organic-soluble Ag nanocrystals large-scale size-controlled synthesis formation mechanism

Study on the isothermal oxidation behavior in air of Ti_(3)AlC_(2) sintered by hot pressing

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science china(Technological sciences) 2006年第5期49卷 513-520页

作者： XU Xuewen1, 2, LI Yangxian1, MEI Bingchu2, ZHU Jiaoqun2, LIU Heyan1 & QU Jingping1 1. School of material science and engineering, Hebei university of Technology, Tianjin 300130, china 2. state Key laboratory of Advanced Technology for materials Synthesis and Processing, Wuhan Univer- sity of Technology, Wuhan 430070, china 1. School of material science and engineering Hebei University of Technology Tianjin 300130 China 2. state Key laboratory of Advanced Technology for materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China

The isothermal oxidation behavior at 900–1300°C for 20 h in air of bulk Ti3AlC2 with 2.8 wt% TiC sintered by means of hot pressing was investigated in the work. The isothermal oxidation behavior generally followed a parabolic rate law. The parabolic rate constants increased from 1.39×10[10] kg[2]·m[4]·s[1] at 900°C to 5.56×10[9] kg[2]·m[4]·s[1] at 1300°C. The calculated activation energy was 136.45 kJ/mol. It was demonstrated that Ti3AlC2 had excellent oxidation resistance due to the continuous, dense; adhesive protect scales consisted of a mass of α-Al2O3; a little of TiO2;/or Al2TiO5. In principle, the oxide scale was grown by the inward diffusion of O[2]; the outward diffusion of Ti[4+]; Al[3+]. The rapid outward diffusion of cations usually resulted in the formation of cracks, gaps,; holes.

关键词： Ti3AlC2, oxidation behavior, kinetics.

Electrolytes in solid-state dye-sensitized nanocrystalline solar cells

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Progress in Natural science:materials International 2006年第7期16卷 679-683页

作者： AN Hongli, XUE Bofei, LI Dongmei, MENG Qingbo and GUO Lin ( Beijing national laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of sciences, Beijing 100080, china department of material science and engineering, Bei Hang university, Beijing 100083, china) [a]Beijing national laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing China [b]department of material science and engineering Bei Hang University Beijing China

In this paper, the structure and operating principle of the dye-sensitized nanocrystalline solar cells (DSSC) are dis- cussed. The electrolytes can be divided into three types: liquid electrolyte, quasi-solid electrolyte and solid electrolyte. Based on the relevant study of our group, we summarized mainly the research progress of the quasi-solid electrolyte and solid electrolyte in solid-state DSSC.

关键词： solar cells electrolytes solid-state dye-sensitized.

A study on compressive shock wave propagation in metallic foams

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science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 279-287页

作者： WANG ZhiHua1,2,ZHANG YiFen2,REN HuiLan1 & ZHAO LongMao2 1 state Key laboratory of Explosion science and Technology,Beijing Institute of Technology,Beijing 100081,china 2 Institute of Applied Mechanics and Biomedical engineering,Taiyuan university of Technology,Taiyuan 030024,china 1. state Key laboratory of Explosion science and Technology Beijing Institute of Technology Beijing 100081 China2. Institute of Applied Mechanics and Biomedical Engineering Taiyuan University of Technology Taiyuan 030024 China

Metallic foam can dissipate a large amount of energy due to its relatively long stress plateau,which makes it widely applicable in the design of structural crashworthiness. However,in some experimental studies,stress enhancement has been observed when the specimens are subjected to intense impact loads,leading to severe damage to the objects being protected. This paper studies this phenomenon on a 2D mass-spring-bar model. With the model,a constitutive relationship of metal foam and corresponding loading and unloading criteria are presented; a nonlinear kinematics equilibrium equation is derived,where an explicit integra-tion algorithm is used to calculate the characteristic of the compressive shock wave propagation within the metallic foam; the effect of heterogeneous distribution of foam microstructures on the shock wave features is also included. The results reveal that under low impact pulses,considerable energy is dissipated during the progressive collapse of foam cells,which then reduces the crush of objects. When the pulse is sufficiently high,on the other hand,stress enhancement may take place,especially in the heterogeneous foams,where high peak stresses usually occur. The characteristics of compressive shock wave propagation in the foam and the magnitude and location of the peak stress produced are strongly dependent on the mechanical properties of the foam material,amplitude and period of the pulse,as well as the homogeneity of the microstructures. This research provides valuable insight into the reliability of the metallic foams used as a protective structure.

关键词： aluminum foam heterogeneous intensive pulse loading stress enhancement

THE ROLE OF INTERFACIAL DIFFUSION IN SRBI2TA2O)9 THIN FILMS CAPACITORS

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THE ROLE OF INTERFACIAL DIFFUSION IN SRBI2TA2O)9 THIN FILMS ...

A three-dimensional k-ε-k_p model in curvilinear coordinates for sediment movement and bed evolution

第8届国际材联电子材料国际研讨会

作者： Aidong Li, Di Wu, Huiqing Ling, Xinhua Zhu, Tao Yu, Zhiguo Liu, Naiben Ming national laboratory of solid state microstructures, nanjing university, nanjing 210093, P. R. china materials science and engineering department, nanjing university, nanjing 210093, P. R. china Center for Advanced Studies in science and Technology of microstructures, nanjing 210093, P. R. china

During preparation of multilayer films, interracial diffusion critically affects film performance. In this report, SrBiTaO (SBT) thin films were prepared on Pt/TiO/SiO/Si substrates using metalorganic decomposition spin-on technique. Impact of different heat treatment processing, film thickness, top electrode postanneal and atmosphere anneal on interfacial diffusion has been investigated by X-ray diffraction (XRD),

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science china(Technological sciences) 2009年第4期52卷 1090-1100页

作者： SHEN YongMing1 & LIU Cheng2 1 state Key laboratory of Coastal and Offshore engineering, Dalian university of Technology, Dalian 116023, china 2 Pearl River Hydraulic Research Institute, Guangzhou 510611, china state Key laboratory of Coastal and Offshore engineering Dalian University of Technology Dalian 116023 China Pearl River Hydraulic Research Institute Guangzhou 510611 China

To aim at the substitution of the magnitude and direction of water flow movement near bed for those of bed load transport in solid-liquid two-phase one-fluid model, and to simulate the effect of secondary flow on transverse bed load transport in channel bends and the effect of bed slope on bed load trans- port in a better way, a three-dimensional k-ε-kp solid-liquid two-phase two-fluid model in curvilinear coordinates is solved numerically with a finite-volume method on an adaptive grid for studying wa- ter-sediment movements and bed evolution in a 120° channel bend. Numerical results show that the trajectories of solid-phase deviate from those of liquid-phase in the channel bend, and the deviation increases with the increase of the particle diameters. The calculated bed deformation by the k-ε-kp model is in better agreement with measured bed deformation than those by one-fluid model. It is proved that the k-ε-kp model can simulate the effect of secondary flow on lateral bed load transport with the higher accuracy than the one-fluid model.

关键词： curvilinear coordinates three-dimensional k-ε-kp model two-fluid model solid-liquid flows channel bend bed load bed evolution tra- jectory

The Properties of Native Silk Fibroin (SF) Solution/Gel from Bombyx mori Silkworms during the Full Fifth Instar Larval Stage

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Journal of Wuhan university of Technology(materials science) 2011年第2期26卷 263-269页

作者：王洪 Key laboratory of Textile science & Technology Ministry of EducationDonghua University

The properties of native silk fibroin （SF） solution in the gland of silkworms during the full fifth instar larval stage were examined in an attempt to elucidate the mechanism of natural silk spinning in the *** flow and gelation behavior,birefringence phenomenon,rheological properties,specific viscosity and conformation of SF solutions from the gland of silkworms were measured by polarized light microscope,HAKKE rheometer,Ubbelohde viscometer and solid-state 13C NMR,*** comparing their properties with regenerated SF solutions from natural silk fibers,it is believed that there exists a progressive maturation process favorable to spin silk fibers with excellent properties from native SF solution and a weak bonded and highly oriented SF gel network with SF molecules partly extended in α-helix conformation is formed in the middle section of the gland of *** suggests that a biomimetic maturation process for making spinnable solution might be necessary for artificial silk fiber spinning in order to obtain improved fiber properties.

关键词： silk fibre spin viscosity sol/gel

Effect of leachate inoculum on biopretreatment of municipal solid waste by a combined hydrolytic-aerobic process

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Journal of Environmental sciences 2009年第8期21卷 1162-1168页

作者： ZHANG Dongqing, HE Pinjing, SHAO Liming state Key laboratory of Pollution Control and Resources Reuse, Key laboratory of Yangtze River Water Environment, College of Environmental science and engineering, Tongji university, Shanghai 200092, china. [a]state Key laboratory of Pollution Control and Resources Reuse Key Laboratory of Yangtze River Water Environment College of Environmental Science and Engineering Tongji University Shanghai 200092 China

The biopretreatment of municipal solid waste by a combined hydrolytic-aerobic process has become of great interest for biostabilization or biodrying. The study aimed at investigating the effect of leachate inoculurn on the biopretreatment. During the hydrolytic stage, the inoculum addition at the ratio of leachate to waste （LWR） of 5% and 7% stimulated the start-up of hydrolysis and enhanced the hydrolysis rate by 27.4% and 24.2%, respectively; whereas the inoculation at LWR of 1% had almost no effect on the hydrolysis rate and the inoculation at LWR of 10% reduced the hydrolysis rate by 12.7%. During the subsequent aerobic stage, the inoculations at LWRs greater than 5% decreased organics degradation rate. As a whole, compared with none inoculation, the total degradation rates of organics for inoculating trials at LWRs of 5%, 7% and 10% decreased by 14.5%, 14.3% and 32.7%, respectively. Correspondingly, their net water removal rates were reduced by 4.4%, 5.8% and 19.0%. The inoculation at LWR of 1% could not significantly affect the biopretreatment. The inoculum addition at LWR of 5% and 7% could shorten hydrolytic stage and thus accelerate the whole combined process. Moreover, the inoculations at LWRs greater than 5% were favorable for lignocelluloses degradation.

关键词： biopretreatment hydrolysis-aeration inoculation leachate municipal solid waste