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Environmental benefits of underground coal gasification

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Journal of Environmental Sciences 2002年第2期14卷 284-288页

作者： liU Shu qin, liU Jun hua, YU li (China university of Mining & Technology, beijing 100083, China. China university of Mining & Technology Beijing 100083 Chin

Environmental benefits of underground coal gasification are evaluated. The results showed that through underground coal gasification, gangue discharge is eliminated, sulfur emission is reduced, and the amount of ash, mercury, and tar discharge are decreased. Moreover, effect of underground gasification on underground water is analyzed and CO 2.disposal method is put forward.

关键词： environmental benefits coal underground coal gasification

Microstructure and Deformation Mechanics of X100 line Pipe Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 255-261页

作者： li Yang 1,2.MENG li 1,JI ling-kang 2.li He-lin 2.(1.School of Material Science and Egineering,university of Sceince and Technology beijing,beijing 100083,China 2.CNPC Tubular Goods Research Institute,Xi’an 710065,China) Univ Sci & Technol beijing Sch Mat Sci & Egineering Beijing 100083 Peoples R China CNPC Tubular Goods Res Inst Xian 710065 Peoples R China

In present paper,microstructure is observed by means of OM,SEM,EBSD and TEM analysis on material obtained from X100 linepipe with wall thickness as 2..6mm and outside diameter as 1016mm diameter Grade *** study the deformation mechanics,microstructure transformation is also investigated on deformed specimens with different strain level as 0%,5% and 8%.Results show that X100 line pipe material consists mainly of acicular ferrite whose ratio in material reaches 64%,obvious cellular structures formed by tangled dislocation and M/A island distributed in acicular plates indicate abundant dislocation and substructure existed in *** is measured that line pipe steel has a much finer effective grain size as 2.07μm,which can results in a higher strength and toughness for line pipe *** analysis for Kikuchi Pattern reveals that the ratio of large-angle boundary is comparatively higher as 55%,implying that line pipe steel has a good *** is observed that the proportion of small-angle grain boundary increases greatly after material deformed,which consequently results in the increment of dislocation and sub-structure.

关键词： X100 line pipe acicular Ferrite M/A grain boundary misorientation

Wave tectono-sedimentary processes in Tarim basin

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Science China Earth Sciences 2005年第11期48卷 1949-1959页

作者： JIN Zhijun1,2. ZHANG Yiwei1 & CHEN Shuping1 1. Key Laboratory for Hydrocarbon Accumulation, Ministry of Education, China university of Petroleum, {2. 102.49, China 2. Exploration and Production Research Institute, China Petroleum & Chemical Corporation, beijing 100083, China 1. Key Laboratory for Hydrocarbon Accumulation Ministry of Education China University of Petroleum 102249 Beijing China 2. Exploration and Production Research Institute China Petroleum & Chemical Corporation 100083 Beijing China

Based on the unconformities, the formation times of structures, and geological wave filtering applied to basin fills of typical wells around the Manjiaer area in the Tarim basin, the wave tectono-sedimentary processes in the Tarim Basin are discussed. The results of geological wave filtering of basin fills of typical wells show that, in time domain, the evolution of the Tarim basin was controlled by various wave processes with the periods of 740±Ma, 2.0±Ma, 100±Ma and 30±Ma. The analyses of basin fills, basin subsidence and unconformities show that the trends of the sedimentary facies belts, depocenters, and centers of subsidence migrated and interchanged periodically with periods of 2.0±Ma. These show the propagation of wave movements in space domain. The wave evolution of the Tarim basin is of significance to understanding the formation of the oil and gas reservoirs in the basin.

关键词： Tarim basin, tectonics, sedimentation, crustal undation, wave evolution

Fabrication and Microstructure of W/Cu Functionally Graded Material

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Journal of university of Science and Technology beijing 2001年第3期8卷 198-202页

作者： Yunhan ling, Jiangtao li, Zhangjian Zhou, Changchun Ge Laboratory of Special Ceramics & Powder Metallurgy, {2. of Science and Technology beijing, beijing 100083, China Univ Sci & Technol beijing Lab Special Ceram & Powder Met Beijing 100083 Peoples R China

W/Cu functionally gradient material (FGM) has excellent mechanical properties since it can effectively relax interlayer thermal stresses caused by the mismatch between their thermal expansion coefficients. W/Cu FGM combines the advantages of tungsten such as high melting point and service strength, with heat conductivity and plasticity of copper at room temperature. Thus it demonstrates satisfactory heat corrosion and thermal shock resistance and will be a promising candidate as divertor component in thermonuclear device. Owing to the dramatic difference of melting point between tungsten and copper, conventional processes meet great difficulties in fabricating this kind of FGMs. A new approach termed graded sintering under ultra-high pressure (GSUHP) is proposed, with which a near 96% relative density of W/Cu FGM that contains a full distribution spectrum (0-100%W) has been successfully fabricated. Suitable amount of transition metals (such as nickel, zirconium, vanadium) is employed as additives to activate tungsten's sintering, enhance phase wettability and bonding strength between W and Cu. Densification effects of different layer of FGM were investigated. Microstructure morphology and interface elements distribution were observed and analyzed. The thermal shock performance of W/Cu FGM was also prelim{2.rily tested.

关键词： tungsten copper sintering functionally graded material composite

Progress of Solid Electrolytes and the Electrochemical Sensors

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Journal of Materials Science & Technology 1997年第3期13卷 173-178页

作者： Yanruo HONG(National Lab. on Solid Electrolytes and Metallurgical Testing Techniques, university of Science and Technology {2.,{2. 100083, China) National Lab. on Solid Electrolytes and Metallurgical Testing Techniques University of Science and Technology Beijing Beijing 100083 China

Four types of solid state electrochemical sensors and their general principles are introduced in the paper. The novel type-IV sensors developed in the last few years are emphasized to study hereafter. The ways to design new electrochemical sensors and the directions to develop new solid electrolytes for new electrochemical sensors are also discussed.

关键词： li Ba Progress of Solid Electrolytes and the Electrochemical Sensors Wang

Theoretical study on thermal decomposition of azoisobutyronitrile in ground state

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Science China Chemistry 2004年第5期47卷 373-380页

作者： SUN Chengke1,2. ZHAO Hongmei1 & li Zonghe1 1. Department of Chemistry, beijing Normal {2., beijing 100875, China 2. Department of Chemistry, Qujing Normal College, Qujing 655000, China 1. Department of Chemistry Beijing Normal University 100875 Beijing China 2. Department of Chemistry Qujing Normal College 655000 Qujing China

The thermal decomposition mechanisms of azoisobutyronitrile (AIBN) in the ground state have been investigated systematically. Based on the potential energy surfaces (PES) of various possible dissociation paths obtained using the semiempirical AM1 method with partial optimization, the density function theory B3LYP/6-311G* method was employed to optimize the geometric parameters of the reactants, the intermediates, the products and the transition states, which were further confirmed by the vibrational analysis. The obtained results show that the re- action process of the two-bond (three-body) simultaneous cleavage Me2.CN)C─ N=N─ C(CN)Me2. 2.e2.CN)C?+N2.is much more favorable than the reaction process of the two one- bond asynchronous cleavage Me2.CN)CN=N─C(CN)Me2.? Me2.CN)CN=N?+ Me2.CN)C?? Me2.CN)C?+ N2. It was suggested that the electron shrinking effect of double bond (─N=N─) in AIBN and the stabilities of the Me2.CN)C?radical as well as N2.molecule are main factors of leading to the reaction proceeding in the former pathway. The calculation results were consistent with all the experimental facts.

关键词： azoisobutyronitrile, radicals, thermal decomposition, density function theory (DFT).

Simulating the impacts of climate variation and land-cover changes on basin hydrology: A case study of the Suomo basin

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Science China Earth Sciences 2005年第9期48卷 1501-1509页

作者： CHEN Junfeng1,2. li Xiubin2.& ZHANG Ming2.1. Institute of Remote Sensing & GIS, Peking university, {2. 100871, China 2. Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, {2. 100101, China 1. Institute of Remote Sensing & GIS Peking University 100871 Beijing China 2. Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing Chin

Impacts of land cover changes on watershed hydrology have been a long-term academic concern with acute dispute. But little attention has been paid to such effects on mesoscale river basins, where the society has a closer link to river hydrology. The present study focuses on a mesoscale river basin, the Suomo Basin that is located on the upper reaches of the Yangtze River. Land covers in the basin in the years 1970, 1986 and 1999 were mapped. A lumped hydrologic model, CHARM, and a distributed hydrologic model, SWAT, were used to model the impacts of both land-cover change and climate variation on river runoff during the past four decades. The results show that the contribution of climate variation to the change of runoff regime makes up 60%―80%, while that of land cover changes only 2.%.

关键词： climate variation, land-cover changes, Suomo Basin, CHARM model, SWAT model.

Overexpression of heme oxygenasel protects smooth muscle cells against oxidative injury and inhibits cell proliferation

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Cell Research 2002年第2期12卷 123-132页

作者： MIN ZHANG, BAO HuI ZHANG, li CHEN, WEI AN1 Institute of Sports Medicine, The Third Hospital, Peking university,{2., China 2.epartment of Cell Biology, Capital university of Medical Sciences, beijing 100054, China 1Institute of Sports Medicine The Third Hospital Peking University Beijing 100083 China 1Institute of Sports Medicine The Third Hospital Peking University Beijing 100083 China 2.epartment of Cell Biology Capital University of Medical Sciences Beijing 100054 China 2.epartment of Cell Biology Capital University of Medical Sciences Beijing 100054 China

To investigate whether the expression of exogenous heme oxygenase-1 (HO-1) gene within vascular smooth muscle cells (VSMC) could protect the cells from free radical attack and inhibit cell proliferation, we established an in vitro transfection of human HO-1 gene into rat VSMC mediated by a retroviral vector. The results showed that the profound expression of HO-1 protein as well as HO activity was 1.8- and 2.0-fold increased respectively in the transfected cells compared to the non-transfected ones. The treatment of VSMC with different concentrations of H2.2.led to the remarkable cell damage as indicated by survival rate and LDH leakage. However, the resistance of the HO-1 transfected VSMC against H2.2.was significantly raised. This protective effect was dramatically diminished when the transfected VSMC were pretreated with ZnPP-IX, a specific inhibitor of HO, for 2. h. In addition, we found that the growth potential of the transfected cells was significantly inhibited directly by increased activity of H

关键词： Heme oxygenase retroviral vector free radical cell proliferation vascular smooth muscle cells.

A case study of spatial heterogeneity of soil moisture in the Loess Plateau,western China:A geostatistical approach

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International Journal of Sediment Research 2009年第1期24卷 63-73页

作者： BI Huaxing1,2.li Xiaoyin3,liU Xin3,GUO Mengxia3,and li Jun3 1 Prof., College of Soil and Water Conservation, beijing Forestry university, beijing 100083, China, Key Laboratory of Soil and Water Conservation and Desertification Combating, Ministry of Education, beijing 100083, China 2.Researcher, Ji-xian National Ecological Station of China, beijing 100083, China 3 Graduate student, College of Soil and Water Conservation, beijing Forestry university, beijing 100083, China [a]Prof. College of Soil and Water Conservation Beijing Forestry University Beijing 100083 China Key Laboratory of Soil and Water Conservation and Desertification Combating Ministry of Education Beijing 100083 China [b]Researcher Ji-xian National Ecological Station of China Beijing 100083 China [c]Graduate student College of Soil and Water Conservation Beijing Forestry University Beijing 100083 China

Soil moisture distribution shows highly variation both spatially and temporally. This study assesses the spatial heterogeneity of soil moisture on a hill-slope scale in the Loess Plateau in West China by using a geostatistical approach. Soil moisture was measured by time-domain reflectometry(TDR) in 313 samples. Two kinds of sampling scales were used(2.x 2.m and 2. x 2. m) at two soil layers(0-30 cm and 30-60 cm). The general characteristics of soil moisture were analyzed by a classical statistics method,and the spatial heterogeneity of soil moisture was analyzed using a geostatistical approach. The results showed that the spherical model is the best-fit model to simulate soil moisture on the experimental hill-slope. The parameters of this model indicated that the spatial dependence of soil moisture in the selected hill-slope was moderate. Even the 2.x 2.m sampling scale was too coarse to show the detailed spatial variances of soil moisture in this area. The dependent distance increased from 2..4 m to 494.16 m as the sampling scale became coarse(from 2.x 2.m to 2. x 2. m). A map of soil moisture was generated by using original soil moisture data and interpolated values determined by the Kriging method. The average soil moisture(area weighted) in the different layers of soil was calculated on the basis of this map(10.94% for the 0-30 cm soil layer,11.88% for the 30-60 cm soil layer). This average soil moisture is lower than the corresponding average effective soil moisture,which suggests that the soil moisture is not sufficient to support vegetation in this area.

关键词： Spatial heterogeneity Soil moisture Geostatistics Loess Plateau of China