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Rare Metals 2010年第5期29卷 505-510页

作者： YI Jin,TAN Chunlin,LI Weishan,LEI Jianfei,and HAO Liansheng School of Chemistry and Environment & Key Laboratory of Electrochemical technology on energy Storage and Power Generation of guangdong Higher Education Institutes,South China Normal {3.,{4.,China School of Chemistry and Environment & Key Laboratory of Electrochemical technology on energy Storage and Power Generation of guangdong Higher Education Institutes South China Normal University Guangzhou China

With the assistance of nonionic surfactant （OP-10） and surface-selective surfactant （CH3.OOH）, anatase TiO2 was prepared as an anode material for lithium ion batteries. The morphology, the crystal structure, and the electrochemical properties of the prepared anatase TiO2 were characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, electrochemical impedance spectroscopy （EIS）, and galvanostatic charge and discharge test. The result shows that the prepared anatase TiO2 has high discharge capacity and good cyclic stability. The maximum discharge capacity is 3.3.mAh.g^-1, and there is no significant capacity decay from the second cycle.

关键词： lithium ion batteries titanium dioxide sol-gel process electrochemical properties sttrfactants

Synthesis and Characterization of Mg_3.PO_4._2-coated Li_(1.05)Ni_(1/3.Mn_(1/3.Co_(1/3.O_2 Cathode material for Li-ion Battery

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Journal of Wuhan university of technology(materials Science) 2009年第3期24卷 347-353页

作者：陈玉红 Department of Chemical and Environmental Engineering Hebei Chemical & Pharmaceutical Vocational Technology Colege

Mg3.PO4.2-coated Li1.05Ni1/3.n1/3.Co1/3.2 cathode materials were synthesized via co-precipitation method. The morphology, structure, electrochemical performance and thermal stability were characterized by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, cyclic voltammetry（CV）, electrochemical impedance spectroscopy（EIS）, charge/discharge cycling and differential scanning calorimeter （DSC）. SEM analysis shows that Mg3.PO4.2-coating changes the morphologies of their particles and increases the grains size. XRD and CV results show that Mg3.PO4.2-coating powder is homogeneous and has better layered structure than the bare one. Mg3.PO4.2-coating improved high rate discharge capacity and cycle-life performance. The reason why the cycling performance of Mg3.PO4.2-coated sample at 55 ℃ was better than that of room temperature was the increasing of lithium-ion diffusion rate and charge transfer rate with temperature rising. Mg3.PO4.2-coating improved the cathode thermal stability, and the result was consistent with thermal abuse tests using Li-ion cells： the Mg3.PO4.2 coated Li1.05Ni1/3.n1/3.o1/3.2 cathode did not exhibit thermal runaway with smoke and explosion, in contrast to the cells containing the bare Li1.05Ni1/3.n1/3.o1/3.2.

关键词： lithium-ion batteries cathode materials Li1.05Ni1/3.n1/3.o1/3.2 co-precipitation

土壤源热泵制冷间歇工况土壤温度响应实验研究

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太阳能学报 2009年第10期30卷 1373-1377页

作者：陈颖杨敏史保新广东工业大学材料与能源学院广州510006

在夏热冬暖的广州地区搭建了两种换热器向土壤放热的实验台,换热器埋地深度为3.m,实验元件有单U和双U两种型式。连续制冷工况下,通过对两口井内土壤温度变化的研究,结果发现,开机12h后,土壤温度趋于稳定;停机12h后两个埋地换热管处的土... 详细信息

在夏热冬暖的广州地区搭建了两种换热器向土壤放热的实验台,换热器埋地深度为3.m,实验元件有单U和双U两种型式。连续制冷工况下,通过对两口井内土壤温度变化的研究,结果发现,开机12h后,土壤温度趋于稳定;停机12h后两个埋地换热管处的土壤温度就可恢复约95%,但土壤温度基本得以恢复需要停机81h。在停机12h后地温恢复得极其缓慢,已没有工程应用价值。可见合理选择运行与停机时间有助于提升系统的整体换热能力和地热的综合利用率。通过实验研究发现,间歇工况下双U井单位井深换热量较之连续运行提高了25.6%,单U井单位井深换热量提高了21.8%。

关键词：土壤源热泵间歇工况双u 单u 温度响应

Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South China

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Science China Earth Sciences 2006年第3期49卷 225-241页

作者： ZUO Jingxun1,2, TONG Jinnan3. QIU Haiou4.& ZHAO Laishi3.1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China 2. Henan Institute of Geological Survey, Zhengzhou 4.0007, China 3. State Key Laboratory of Geological Processes and Mineral Resources at China university of Geosciences, Wuhan 4.0074. China 4. Faculty of material Sciences and Chemical Engineering, China university of Geosciences, Wuhan 4.0074. China 1. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Henan Institute of Geological Survey Zhengzhou 450007 China 3. State Key Laboratory of Geological Processes and Mineral Resources at China university of Geosciences Wuhan 430074 China 4. Faculty of material Sciences and Chemical Engineering China University of Geosciences Wuhan 430074 China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South China, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 13. background values are intensively controlled by palaeogeographic environment. In general, δ 13. values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze Region.

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 university, Xi’an 71004., China 3. School of material Science and Engineering, university of Science and {4. 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

The Algorithm of Intelligent Compensation in Flexible material Processing

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武汉理工大学学报 2006年第S1期28卷 162-166页

作者： TANG Luxin,DENG Xiaohui,LIU Zhiyuan (School of Information Engineering guangdong university of technology,guangzhou 510006,China) School of Information Engineering guangdong university of technology Guangzhou 510006China

Flexible material is easy to be distorted in high speed sewing process,so it must be tracked in the process. In this paper,The mathematics model is established with computer visual measure and digital image process for distorted flexible material. By the means of optimizing initial iterative value,the distorted variable of two correlated subareas evaluated. The method based on improved steepest descent algorithm and simulation annealing algorithm is proposed. It has been proven that the evaluating the algorithm’s error and convergent speed by the method of numerical emulate is the effective approach.

关键词： distorted flexible material visual measurement correlated algorithm

Analysis for twinning and slip in face-centered cubic crystals under axisymmetric co-deformation

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Science China(Technological Sciences) 2006年第5期49卷 521-536页

作者： CHEN Zhiyong1,2, CAI Hongnian1, ZHANG Xinming2, WANG Fuchi1 & TAN Chengwen1,3.1. School of material Science and Engineering, Beijing Institute of technology, Beijing 100081, China 2. School of material Science and Engineering, Central South {3., Changsha 4.0083. China 3. School of material Science and Engineering, Beijing {3. of Aeronautics and Astronautics, Beijing 100083. China 1. School of material Science and Engineering Beijing Institute of Technology Beijing 100081 China 2. School of material Science and Engineering Central South University Changsha 410083 China 3. School of material Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

The maximum work principle of Bishop-Hill was developed to analyze the axisymmetric co-deformation in face-centered cubic crystals (f.c.c.) for twinning on {111} 112 and slip on {111} 110 systems. The influence of ξ , the ratio of critical re- solved shear stress for twinning to slip, on the yield stress states and corresponding active slip or/and twinning systems for orientations in the standard stereographic triangle of cubic crystal was investigated systematically. The Taylor factors and the anisotropy of yield strength for three important orientations [100], [110] and [111] in orientation space were analyzed. It is found that the yield strength asymmetry for the case of axisymmetric de- formation of tension and compression can be explained based on the microscopic theory of crystal plasticity. The concept of orientation factor for twinning ability was proposed and the deformation mechanism map in the orientation space was established for the case of axisymmetric deformation. The deformation texture formation and development of f.c.c. crystals with low stacking fault energy for axisymmetric tension can be explained qualita- tively on the basis of analyzed results.

关键词： twinning slip face-centered cubic crystals axisymmetric co-deformation Bishop-Hill maximum work principle yield strength anisotropy

Microwave peak absorption frequency of liquid

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Science China(Physics,Mechanics & Astronomy) 2008年第9期51卷 1254-1263页

作者： HAN GuangZe1 & CHEN MingDong2 1 Department of Physics,South China university of technology,guangzhou 5106{3.,China 2 guangzhou Auto College,South China university of technology,guangzhou 510800,China 1. Department of Physics South China University of Technology Guangzhou 510640 China 2. guangzhou Auto College South China University of Technology Guangzhou 510800 China

Microwave-assisted extraction is a new effective method which has practical ap-plications in many fields. Microwave heating is one of its physical mechanisms,and it also has the characteristic of selectivity. When the applied microwave fre-quency equals a certain absorption frequency of the material (or specific compo-nent),the material will intensively absorb microwave energy. This is also known as resonant absorption,and the frequency is called the peak absorption frequency which depends on the physical structure of the material. In this work,dynamic hy-drogen bond energy was included in molecular activation energy; with the liquid cell model,the expression of interaction energy between dipolar molecules was derived. The rotational relaxation time was gotten from the Eyring viscosity formula. Then based on the relationship between dielectric dissipation coefficient and re-laxation time,the expression of microwave peak absorption frequency as a func-tion of the material physical structure,rotational inertia and electrical dipole mo-ment of molecules was established. These theoretical formulas were applied to water and benzene,and the calculated results agree fairly well with the experi-mental data. This work can not only deepen the study of the interaction between microwave and material,but also provide a possible guide for the experiment of microwave-assisted extraction.

关键词： microwave-assisted extraction microwave heating relaxation time liquid viscosity peak absorption fre-quency

Geochemistry of high-Mg andesites from the early Cretaceous Yixian Formation, western Liaoning: Implications for lower crustal delamination and Sr/Y variations

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Science China Earth Sciences 2006年第9期49卷 904-914页

作者： WANG Xiaorui1, GAO Shan1,2, LIU Xiaoming1, YUAN Honglin1, HU Zhaochu1, ZHANG Hong1,3.& WANG Xuance4.1. State Key Laboratory of Continental Dynamics, Department of Geology, Northwest university, Xi`an 710069, China 2. State Key Laboratory of Geological Processes and Mineral Resources, China university of Geosciences, Wuhan 4.0074. China 3. Shenyang Institute of Geology and Mineral Resources, Shenyang 11003., China 4. guangzhou Institute of Geochemistry, Chinese Academy of Sciences, guangzhou 51064., China 1. State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an 710069 China 2. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China 3. Shenyang Institute of Geology and Mineral Resources Shenyang 110032 China 4. guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

85 volcanic rocks of the Yixian Formation from the Sihetun type section werecollected and analyzed for geochemical and isotopic compositions. Major element compositionsindicate that the Sihetun volcanic rocks are high magnesium andesites with some basalts occurring atthe bottom of section. The Sihetun high magnesium andesites (SiO_2 = 52.82-59.3. wt%, Al_2O_3.14.15-16.3.wt%) show many characteristics of adakites such as depletion in heavy rare-earth elements(HREE; Yb = 1.03.1.88 μg/g) and Y(12-20 μg/g) and high Sr (620-13.3.μg/g) and Sr/Y(3.-88), withhigh La_N/Yb_N ratio (10-25). They share similar major and trace element characteristics to volcanicrocks from the Xinglonggou Formation except their lower Nd isotope ratios (^(14.)Nd/^(14.)Nd(13.Ma) = 0.5118-0.5119, ε_(Nd) (13.Ma) = -11.6-13.8, ^(87)Sr/^(86)Sr (13. Ma) = *** were interpreted in a way that eclogite that formed at the base of thickened Archean lowercrust of the North China craton foundered into the convecting mantle and subsequently melted andinteracted with peridotite. However, compared to the Xinglonggou volcanic rocks, the source of theSihetun magma contained more ancient continental crustal {3. in order to explain its evolved Ndisotopes. The age of the Sihetun Formation was 120 to 13. Ma, and this indicates that delaminationlasted to the early Cretaceous period. The Sr contents and Sr/Y ratios of the Sihetun high-Mgandesites show significant negative correlations with SiO_2 for samples with SiO_2 > 56%. Thesesuggest that the Sr and Sr/Y values were reduced due to fractional crystallization of ***, the effect of crystallization on volcanic Sr and Sr/Y ratio has to be taken intoaccount.

关键词： High-Mg andesite, Adakite, Yixian Formation, North China Craton, delamination.

Early Hydration of Composite Cement with Thermal Activated Coal Gangue

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Journal of Wuhan university of technology(materials Science) 2010年第1期25卷 162-166页

作者：郭伟 Department of material Engineering Yancheng Institute of Technology Institute of material Science and Engineering Nanjing University of Technology

Composite cement samples were prepared by mixing clinker, gypsum with burnt coal gangues which was calcined at various temperatures. The mechanical strength and Ca（OH）2 content in the cement paste were tested, and the paste composition and microstructure were analyzed by thermogravimetry-differential thermal analysis （TG-DSC）, X-ray diffraction（XRD）, scanning electronic microscopy （SEM） and pore structure analysis. Results demonstrate that the thermal activated coal gangue could accelerate the early hydration of cement clinker obviously, which promotes the gangue hydration itself. The early hydrated products of the cement are C-S-H gel, Ca（OH）2 and AFt. The cement with 3.% （in mass） the gangue exhibits higher mechanical strength, and among all the cement samples the one with the gangue burnt at 700 ℃ displays the highest hydration rate, mechanical strength, the most gel pores and the lowest total porosity.

关键词： blended cement hydration microstructure hydration product