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Determination of the Thermal Expansion Coefficient of Concrete at Early Ages by Using Temperature-stress Testing Machine

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Journal of wuhan university of Technology(Materials Science) 2006年第4期21卷 146-149页

作者：霍凯成 hubei key {2. of Roadway Bridge & {3. Engineering Wuhan University of TechnologyWuhan 430070China

By using the uptodate temperatuer-stress testing machine, the thermal expansion coefficient of concrete at early ages was studied and indicative conclusions were achieved ： temperature rising due to hydration heat is not directly correlated with cracking, but the temperature and stress evolation process should be taken into consideration in the same time. Proper chemical admixtures and mineral cornpasitions can improve the mechanical properties of concrete such as thermal expansion coefficient, which is very indicative in practice.

关键词： concrete coefficient of thermal expansion temperature-stress test

Exsolution of ilmenite and Cr-Ti magnetite from olivine of garnet-wehrlite

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Science china Earth Sciences 2005年第9期48卷 1368-1376页

作者： LIU Xiangwen1,2. JIN Zhenmin1,3. QU Jing2.& WANG Lu2.1. State key {2. of Geological Processes and Mineral Resources, china {3. of Geosciences, wuhan 43.074, china 2. Graduate School of china {3. of Geosciences, wuhan 43.074, china 3. Faculty of Earth Sciences, china {3. of Geosciences, wuhan 43.074, china 1. State key laboratory of Geological Processes and Mineral Resources China University of Geosciences 430074 Wuhan China 2. Graduate School of china university of Geosciences 430074 Wuhan China 3. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China

Exsolution of rod-like ilmenite (Ilm) and Cr-Ti magnetite (Mt) have been found in olivine of garnet-wehrlite from the core of Chinese Continental Sciences Drilling (CCSD). Their composition, morphology, crystal structure and their topotaxies with host olivine have been studied in detail by the transmission electron microscopy (TEM) and electron probe microanaly- sis (EPMA) technique. It shows that rod-like Ilm exsolution reported in this paper has similar characteristic with that of Alpe Arami olivine, while Cr-Ti magnetite exsolution mentioned in this paper has large discrepancy with chromite exsolution in Alpe Arami olivine. These observations suggest that both of the exsolutions found in this paper should be solid solution phases in β-olivine at their first period, then experiencing decomposition of solid solution and therefore forming Ilm and Cr-Ti magnetite exsolution with the pressure decreasing. So, this garnet-wehrlite perhaps had been ever located in mantle transition zone with a minimum depth of 3.0 km.

关键词： garnet-wehrlite, ilmenite, magnetite, exsolution, CCSD.

Subsidence control and farmland conservation by solid backfilling mining technology

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中国有色金属学会会刊：英文版 2011年第S3期21卷 665-669页

作者： GUO Guang-li1, 2. FENG Wen-kai3. ZHA Jian-feng1, 2. 3. LIU Yuan-xu1, 2. WANG Qiang1, 2.1. {2. laboratory for Land Environment and Disaster Monitoring of the State Bureau of Surveying and Mapping, china {3. of Mining and Technology, Xuzhou 2.1116, china 2. Jiangsu {2. laboratory of Resources and Environmental Information Engineering, china {3. of Mining and Technology, Xuzhou 2.1116, china 3. State {2. laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu {3. of Technology, Chengdu 610059, china [a] key laboratory for Land Environment and Disaster Monitoring of the State Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China [b] Jiangsu key laboratory of Resources and Environmental Information Engineering China University of Mining and Technology Xuzhou 221116 China [c] State key laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China

Solid backfilling mining technology, which decreases the height of fissure zone and caving zone, and alleviates the subsidence, is a new technology for farmland conservation. Based on the situation analysis of farmland destruction in mining area, three ways for farmland protection were proposed. In order to improve the feasibility of this technology, the limited filling materials should be used to increase resources recovery ratio, and then the surplus materials could be backfilled into goaf. An index, namely farmland conservation ability, was put forward to optimize the ways for farmland conservation. At last, the Wanbei coal mine was taken as a case for farmland conservation. It was shown that 3.40 t dull coal was substituted and 52.hm2.farmland was conserved by solid backfilling mining in this coal mine.

关键词： solid backfilling farmland conservation mining subsidence equivalent mining height

Mining subsidence control by solid backfilling under buildings

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中国有色金属学会会刊：英文版 2011年第S3期21卷 670-674页

作者： ZHA Jian-feng1, 2. 3. GUO Guang-li1, 2. FENG Wen-kai3. WANG Qiang1, 2.1. {2. laboratory for Land Environment and Disaster Monitoring of the State Bureau of Surveying and Mapping, china {3. of Mining and Technology, Xuzhou 2.1116, china 2. Jiangsu {2. laboratory of Resources and Environmental Information Engineering, china {3. of Mining and Technology, Xuzhou 2.1116, china 3. State {2. laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu {3. of Technology, Chengdu 610059, china [a] key laboratory for Land Environment and Disaster Monitoring of the State Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China [b] Jiangsu key laboratory of Resources and Environmental Information Engineering China University of Mining and Technology Xuzhou 221116 China [c] State key laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China

Solid backfilling mining can reduce the buildings' damage caused by mining greatly. The reduction of subsidence value, the slow advancing speed and the subsidence caused by backfilling body compaction are the main reasons that solid backfilling mining velocity decreases significantly. Based on the research of mechanism, some principles on subsidence control of solid backfilling mining under buildings were proposed. The equivalent mining height was designed according to the fortification criteria of buildings and their attachment structures, which enables the ground movement and deformation caused by mining to be less than the corresponding fortification criteria.

关键词： solid backfilling mining subsidence control mining under buildings

Stress distribution rule of roadway affected by overhead mining in gently inclined coal seams group

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中国有色金属学会会刊：英文版 2011年第S3期21卷 529-535页

作者： KANG Qin-rong1, 2. TANG Jian-xin1, 2. HU Hai1, 2. ZHANG Wei-zhong1, 3.1. College of Resource and Environmental Sciences, Chongqing university, Chongqing 40003., china 2. State key {3. of Coal Mine Disaster Dynamics and control, Chongqing university, Chongqing 40003., china 3. School of Safety Science and Administration, Zhongnan university of Economics and Law,{12., china [a] College of Resource and Environmental Sciences Chongqing University Chongqing 400030 China [b] State key laboratory of Coal Mine Disaster Dynamics and {2. Chongqing University Chongqing 400030 China [c] School of Safety Science and Administration Zhongnan University of Economics and Law Wuhan 430074 China

In light of the severe deformation and destruction of the district raise tunnel in the mining area at the northern part of the Lubanshan colliery, by the theoretic analysis and numerical simulation, both the mining stress distribution in seams group and the deformation and destruction mechanism of floor district raise were investigated. The results show that, at the maximum vertical distance of 40 m, the abutment stress has an influence on the recovery of 2. and 3. coal seam and 8# coal seam at distance of 3. m. As a result, the recovery of 8# is rather than those of 2. or 3. coal seam, which contributes to the deformation and destruction of the district raise surrounding rock. The major factors affecting the abutment stress include the mining depth, mining height, residual gob space, adjacent working faces and short spacing coal seam recovery.

关键词： coal seams group stress distribution district raise surrounding rock deformation and destruction abutment stress

Long-Term Cumulative Damage Model of Historical Timber Member under Varying Hygrothermal Environment

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wuhan university Journal of Natural Sciences 2009年第5期14卷 430-436页

作者： WANG Xueliang,QU Weilian hubei key {2. of Roadway Bridge and {3. Engineering,wuhan university of Technology,wuhan 43.070,hubei,china hubei key {2. of Roadway Bridge and {3. Engineering Wuhan University of Technology Wuhan 430070 Hubei China

A long-term damage cumulative model for the duration of load effect of structural timber is proposed in this paper, which is economical in analysis as well as involving long-term hygrothermal effect. Based on the Miner linear damage cumulative theory, the cumulative damage model is applied to analyze the annual hygrothermal, daily cyclic thermal and daily cyclic relative humidity＇s effect on load-duration behavior and to calculate the sum of damage in one year. The results indicate that the annual and daily hygrothermal effect should be taken into consideration when calculating the damage accumulation, in which the influence levels from large to small are annual hygrothermal, daily relative humidity and daily thermal effect, Considering both annual and daily hygrothermal variations as external loads the long-term model is determined. Its application to service-life prediction of a historic timber structure verifies the feasibility and high-efficiency of the proposed approach.

关键词： daily hygrothermal effect annual hygrothermal effect structural timber long-term cumulative damage model

Investigation on Vibrational Spectra and structures of 4-Mercaptopyridine Monomer and Its Dihydrate

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Chemical Research in Chinese Universities 2006年第1期22卷 90-93页

作者： CHENG Jian-bo 1,2., XUE Wei-qing 1 , ZHAO Bing 1** , ZHANG Gang 3.and GONG Bao-an 2.1. key {2. for Supramolecular structure and Material of Ministry of Education, Jilin {3., Changchun 13.012. P. R. china 2. Science and Engineering College of Chemistry and Biology, Yantai {3., Yantai 2.4005, P. R. china 3. State key {2. of Theoretical and Computational Chemistry, Jilin {3., Changchun 13.02.0} P. R. china [a]key laboratory for Supramolecular {2. and Material of Ministry of Education Jiln University Changchun 130012 P. R. China[b]Science and Engineering College of Chemistry and Biology Yantai University Yantai 264005 P. R. China[c]State Key Laboratory of Theoretical and Computational Chemistry Jiln University Changchun 130023 P. R. China

The optimized molecular structures and vibrational frequencies of 4-mercaptopyridine(4MPY) monomer and its dihydrate were studied by means of the density functional theory(DFT), viz. B3.YP method with the 6-3.1++G(d,p) basis set. On the basis of the calculations, the assignments of the vibrational spectra of the monomer and the dihydrate were performed, and so were investigated the changes in the structure and the vibrational spectrum of the dihydrate as well as the intermolecular force resulting in the formation of the dihydrate. The calculated results show that each of the water molecule planes is vertical to the pyridine ring plane in the dihydrate that is formed via the H-bonds between 4MPY and water molecules. Furthermore, the structure and the vibrational spectrum of 4MPY can be consi- derably affected by the water molecules.

关键词： 4MPY Dihydrate Vibrational spectra DFT Molecular structure

Test of magnetic susceptibility and grain-size age models of loess

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Progress in Natural Science:Materials International 2007年第11期17卷 1312-1317页

作者： Chen Yimeng1,2.3. Feng Zhaodong4 and Gong Huili1,2.1. MOE and key {2. of Resources Environment and GIS of Beijing, Beijing 10003., china 2. key {2. of 3. information Acquisition and Application, The Capital Normal university, Beijing 10003., china 3. Department of Economics & Management of Huizhou university, Huizhou 516007, china 4. key {2. of Western china’s Environmental Systems, Ministry of Education, Lanzhou university, Lanzhou 73.000, china) MOE and key laboratory of Resources Environment and GIS of Beijing Beijing 100037 China key laboratory of {2. information Acquisition and Application The Capital Normal University Beijing 100037 China Department of Economics & Management of Huizhou university Huizhou 516007 China key laboratory of Western{2.’s Environmental Systems Ministry of Education Lanzhou University Lanzhou 730000 China

Ages of the stratigraphic boundary MIS1/2.and MIS3.4 of the Yuanbu loess section in Linxia are used as the basis of the nodal control age. The age of MIS1/2.and MIS3.4 are obtained from the latest international research result—the climatic events recorded in the stalagmite in the Hulu Cave in Nanjing, that MIS1/2.is 11.5 kaB.P. and MIS3.4 is 59.8 kaB.P.. The ages of the two climatic events contain three nodal age control models (Model 1: 0 kaB.P.—59.8 kaB.P.; Model 2. 0 kaB.P.—11.5 kaB.P. and 11.5 kaB.P.—59.8 kaB.P.; Model 3. 11.5 kaB.P.—59.8 kaB.P.), which are used as the nodal control age separately. The deposition times of various stratigraphic horizons are calculated by using the magnetic susceptibility age model and grain-size age model, and then compared with each other. In addition, the AMS14C age, OSL age and the ages of YD and H events are compared with the ages of the corresponding horizons calculated by the three models of nodal control ages. From the analyses of lithologic characters and climatic stages it has been found that both the magnetic susceptibility age model and the grain-size age model have some defects. Because the accurate control ages are selected as the nodal points of the glacial period or interglacial period, the stratigraphic deposition times determined by the high resolution of magnetic susceptibility age model and grain-size age model approximate to the actual ages. As for the relative accuracy of the two age models, the magnetic susceptibility age model is more accurate than the grain-size age model.

关键词： loess nodal control age magnetic susceptibility age model grain-size age model test

Adsorption of surfactants onto acrylic ester resins with different pore size distribution

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Science china Chemistry 2006年第5期49卷 445-453页

作者： YANG Weiben1,2.3.LI Aimin1,3.CAI Jianguo1,3.MENG Guanhua1,3.& ZHANG Quanxing1,3.1. State key laboratory of Pollution control and Resource Reuse,School of the Environment,Nanjing {3.,Nanjing 2.0093.china 2. Nanjing College of Chemical Technology,Nanjing 2.0048,china 3. Jiangsu Engineering & Technology Research Center for Organic Toxicant control and Resource Reuse,Nanjing 2.003.,china 1. State key laboratory of Pollution {2. and Resource Reuse School of the Environment Nanjing University Nanjing 210093 China 2. Nanjing College of Chemical Technology Nanjing 210048 China 3. Jiangsu Engineering & Technology Research Center for Organic Toxicant control and Resource Reuse Nanjing 210038 China

In this study, a series of acrylic ester resins with different pore size distribution were prepared successfully by varying the type and the amount of pore-forming agents. In order to inves-tigate the adsorption behavior and mechanism of surfactants on acrylic ester resins, three kinds of surfactants were utilized as adsorbates that were sodium 6-dodecyl benzenesulfonate (6-NaDBS), sodium 1-dodecyl benzene sulfonate (1-NaDBS) and sodium 1-dodecyl sulfonate, respectively. It was observed that the surface area was available in a particular pore size and an appropriate pore size of resins appeared to be more important for the adsorption of surfactants. As compared to commercial acrylic ester resins XAD-7 and HP2.G, 50# and 3.# resins exhibited more excellent adsorption properties toward 1-NaDBS and 6-NaDBS. The experimental equilibrium data were fitted to the Langmuir, and double-Langmuir models. Two models provided very good fittings for all resins over the temperature range studied. The investigation indicated that electrostatic attraction and hydrogen bond between resins and surfactants were the main forces and had an obvious effect on adsorption proc-ess.

关键词： acrylic ester resin, surfactant, adsorption, pore size distribution, isotherm.