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Recent change of the ice core accumulation rates on the qinghai-Tibetan Plateau

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Chinese Science Bulletin 2002年第20期47卷 1746-1749页

作者： Shugui Hou Dahe Qin Tandong Yao Dongqi Zhang Tuo Chen Chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst Key Lab Ice Core & Cold Reg Environm Lanzhou 730000 Peoples R China

Three ice cores recovered from the Himalayas (i.e. the East Rongbuk Glacier and the Far East Rongbuk Glacier at Mt. Qomolangma (Everest), and the Dasuopu Glacier at Xixiabangma) show a sharp decline in the accumulation rates since the 1950s, which is consistent with the precipitation fluctuation over India and the low northern latitude zone (5°-35癗). Correspondingly, an increasing trend is observed for the ice core accumulations from the central and northern qinghai-Tibetan Plateau (i.e. the Xiao Dongkemadi Glacier in the central Tanggula Mountains, the Guliya Ice Cap in the western Kunlun Mountains, and the Dunde Ice Cap in the Qilian Mountains) since the 1950s, which is consistent with the precipitation fluctuation over the middle-high northern latitude zone (35°-70°N). However, the variation magnitude of the high-elevation ice core accumulations is more significant than that of precipitation at the low-eleva- tion places, suggesting its extra sensitivity of high-elevation areas to climatic change.

关键词： qinghai-Tibetan Plateau ice core accumulation climatic change.

Study on ground temperature change and characteristic response of engineering geology of permafrost along qinghai-Tibet Railway

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Science China(Technological Sciences) 2003年第z1期46卷 78-90页

作者： PAN Weidong, WANG Quancai, YU Shaoshui & ZHANG Xiaoyan Department of Mechanics, School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China institute of Mountain Hazards and Environment, Chinese Academy of Sciences and Ministry of Water Resources, Chengdu 610041, China State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions Environment and Engineering Research institute, Chinese Academy of Sciences, Lanzhou 730000, China Sichuan Provincial Communications Department, Chengdu 610041, China Lanzhou Univ Dept Mech Sch Phys Sci & Technol Lanzhou 730000 Peoples R China Chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China Chinese Acad Sci State Key Lab Frozen Soil Engn Cold & Arid Reg Environm & Engn Res Inst Lanzhou 730000 Peoples R China Sichuan Prov Commun Dept Chengdu 610041 Peoples R China

Along with the global warming in the recent scores of years, comparatively big changes have taken place in the weather and other environmental conditions of the permafrost area in the qinghai-Tibet Plateau, and very big changes have also occurred in the engineering geological conditions of the permafrost area. Based on a large volume of field survey data, this paper discusses the regularities of horizontal and vertical distribution of permafrost, with its focus of analysis on the temperature change characteristics of the soil in different frozen-soil zones, as well as presents simulation analysis and research for the engineering geologic characteristic response changes that would occur in the future when the temperature of the frozen soil in different zones rises by 1 and 2.6℃ respectively, which will have a tremendous impact on the stability of constructional work.

关键词： qinghai-Tibet Railway, permafrost, ground temperature, engineering geological characteristic.

A study on correlativity between qinghai-Tibet Plateau thermal infrared remote sensing data and underground temperature

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Science China(Technological Sciences) 2006年第z2期49卷 114-120页

作者： HAN Liqun, BI Siwen & SONG Shixin School of Information Engineering, Beijing Technology and Business University, Beijing 100037, China Key Laboratory of Remote Sensing Information Sciences, institute of Remote Sensing Applications, Chinese Academy of Sciences, Beijing 100101, China Beijing Technol & Business Univ Sch Informat Engn Beijing 100037 Peoples R China Chinese Acad Sci Inst Remote Sensing Applicat Key Lab Remote Sensing Informat Sci Beijing 100101 Peoples R China

Based on an analysis of the correlativity between qinghai-Tibet Plateau thermal infrared remote sensing data (QPTIRSD) and underground temperature field distribution, the main factors which obviously influence underground-layer temperatures were derived. Using neural network technology, a model was built to compute underground temperatures via parameters out of the inversion of thermal infrared remote sensing (TIRS) and then analyze the correlativity between above-ground parameters and underground temperatures. This method offers a new way to apply TIRS in monitoring the suture zone of a large-area massif as well as to research structural thermal anomalies.

关键词： qinghai-Tibet Plateau, TIRS, artificial neural network, temperature.

Analysis of the effects of rising temperature for embankments under seismic loads in cold regions

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Research in Cold and Arid Regions 2009年第4期1卷 316-321页

作者： ZhiQiang Liu 1,2,Hao Lu 1 1.School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou,Gansu 730070,China.2.State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research institute,Chinese Academy of Sciences,Lanzhou,Gansu 730000,China. Lanzhou Jiaotong Univ Sch Civil Engn Lanzhou 730070 Gansu Peoples R China Chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst State Key Lab Frozen Soil Engn Lanzhou 730000 Gansu Peoples R China

The effect of temperature rising for frozen soil because of dynamic load was investigated by indoor *** and railway embankments are always loaded by dynamic loads such as earthquakes and *** the qinghai-Tibetan Plateau is a re-gion where earthquakes occur frequently,it is essential to consider the temperature-rising effect of earthquakes or vehicles on railway and road *** this paper and according to the theories of heat transfer and dynamic equilibrium equations,as-suming frozen soil as thermal elastic-viscoplastic material,taking the combination of thermal and mechanical stresses into account,we present the numerical formulae of this dynamic problem,and the computer program of the two-dimensional finite element is *** the program,the dynamic response analyses for embankments loaded by earthquake are worked *** in-dicated that the temperature-rising effect result from earthquakes for embankment in nonuniform distribution in some small areas,the maximum rising temperature is 0.16 ?C for consideration in this paper.

关键词： qinghai-Tibetan railway temperature-rising effect frozen soil embankment

Effects of metal ions on the morphology of calcium sulfate hemihydrate whiskers by hydrothermal method

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Frontiers of Chemical Science and Engineering 2017年第4期11卷 545-553页

作者： Liu, Tianjie Fan, Hao Xu, Yanxia Song, Xingfu Yu, Jianguo East China Univ Sci & Technol Natl Engn Res Ctr Integrated Utilizat Salt Lake R Shanghai 200237 Peoples R China

The effects of Na＋, concentrations on the crystal Mg2＋, A13＋ and Fe3＋ ion morphology of calcium sulfate hemihydrate whiskers formed via a hydrothermal method have been studied. In the presence of A13＋ concentrations higher than 1x10-3 mol/L the whiskers were significantly shorter and thicker and the presence of Mg2＋ and Fe3＋ resulted in shorter whiskers. The presence of Nan did not affect the morphology of the whiskers. Through elemental analysis, it was determined that Mg2＋ and A13＋ were selectively adsorbed on the surfaces of the crystals, whereas Fe3＋ underwent a hydrolysis reaction to form a brown precipitate which decreased the ion concentration in the solution. These results indicate that in raw materials used for the industrial preparation of calcium sulfate whiskers, AI3＋ and Fe3＋ should be removed and the Mg2＋ concentration should be less than 8 x 10-3 mol/L in order to obtain pure whiskers with high aspect ratios.

关键词： metal ions morphology calcium sulfatehemihydrate whiskers hydrothermal method selectiveadsorption