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

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research in cold and {2. 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 {12. 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

陆地生态系统碳源与碳汇及其影响机制研究进展

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生态学杂志 2005年第1期24卷 37-42页

作者：李玉强赵哈林陈银萍中国科学院寒区旱区环境与工程研究所兰州730000 兰州交通大学环境与市政工程学院兰州730070

全球碳循环研究中发现 ,目前已知碳源与碳汇不能达到平衡 ,存在一个很大的碳失汇。大气、海洋和陆地生态系统是人工源CO2.的 3个可能的容纳汇 ,其中陆地生态系统最复杂、最具不确定性 ,因此陆地生态系统碳源与碳汇研究是全球碳循环研究... 详细信息

全球碳循环研究中发现 ,目前已知碳源与碳汇不能达到平衡 ,存在一个很大的碳失汇。大气、海洋和陆地生态系统是人工源CO2.的 3个可能的容纳汇 ,其中陆地生态系统最复杂、最具不确定性 ,因此陆地生态系统碳源与碳汇研究是全球碳循环研究的核心问题之一。大气成分监测、CO2.通量测定、森林资源清查以及模型模拟等方面的研究都表明 ,CO2.施肥效应、氮沉降增加、污染、全球气候变化以及土地利用变化 ,是影响陆地生态系统碳储量的主要生态机制 ,但不确定在过去的 10～ 10 0年以及未来哪一种机制起最主要的作用。

关键词：陆地生态系统碳源碳汇影响机制

Seasonal transition and its boundary layer characteristics in Anduo area of Tibetan Plateau

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Progress in Natural Science:Materials International 2005年第3期 47-53页

作者： ZUO Hongchao ˇˇ ,HU Yinqiao,LI Dongliang,L Shihua and MA Yaoming (cold and arid {2. environmental and engineering research institute,Chinese academy of sciences,lanzhou730000,china) cold and arid {2. environmental and engineering research institute Chinese Academy of Sciences Lanzhou 730000 China

Using the data,especially the GPS rawinsode data,observed in Anduo area of the Tibetan Plateau during the intensive observation period of GAME/Tibet in1998,the transition from the dry to the rainy season along with their boundary layer characteristics is analyzed *** result shows that the formation of the rainy season in Anduo area is related closely to the general atmo-spheric *** westerly belt moving north and the southeast damp current are basic conditions for development of the rainy season in Anduo *** the dry season,the air is drier,air temperature higher,and the atmospheric boundary layer is strongly developed to cause its maximum height to reach *** the sensible heat flux is dominant,and the latent heat flux is small in the in-teraction of land-atmosphere energy exchange,and a reverse humidity phenomenon occurs *** the rainy season,the air is damper,air temperature lower,and the ABL height,with maximum of only about2.00m,is *** the sensible heat flux becomes much smaller,the latent heat flux much larger in the interaction of land-atmosphere energy *** reverse humidity phenomenon disappears.

关键词： dry season rainy season seasonal transition general atmospheric circulation land-atmosphere energy exchange.

Experimental study of surface texture and resonance mechanism of booming sand

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Science china Earth sciences 2007年第9期50卷 1351-1358页

作者： QU JianJun1, ZHANG KeCun1, SUN Bo2. JIANG ShengXiang3, DONG GuangRong1, ZU RuiPing1 & FANG HaiYan 1 Key Laboratory of Desert and Desertification, cold and arid {2. environmental and engineering research institute, Chinese academy of sciences, lanzhou 730000, china 2.Shanghai institute of Polar {2., Shanghai 2.0000, china 3 lanzhou institute of Chemical Physics, Chinese academy of sciences, lanzhou 730000, china 1. Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. Shanghai institute of Polar regions Shanghai 210000 China 3. lanzhou institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

The sound-producing mechanism of booming sand has long been a pending problem in the blown sand physics. Based on the earlier researches, the authors collected some silent sand samples from Teng- ger Desert, Australian Desert, Kuwait Desert, beaches of Hainan Island and Japanese coast as well as the soundless booming sand samples from the Mingsha Mountain in Dunhuang to make washing ex- periments. In the meantime the chemical corrosion experiment of glass micro-spheres, surface coating experiment and SEM examination were also conducted. The experimental results show that the sound production of booming sand seems to have nothing to do with the presence of SiO2.gel on the surface of sand grains and unrelated to the surface chemical composition of sand grains but is related to the resonance cavities formed by porous (pit-like) physical structure resulting from a number of factors such as wind erosion, water erosion, chemical corrosion and SiO2.gel deposition, etc. Its resonance mechanism is similar to that of Hemholz resonance cavity. Under the action of external forces, nu- merous spherical and sand grains with smooth surface and porous surface are set in motion and rub with each other to produce extremely weak vibration sound and then become audible sound by human ears through the magnification of surface cavity resonance. However the booming sands may lose their resonance mechanism and become silent sand due to the damping action caused by the invasion of finer particles such as dust and clay into surface holes of sand grains. Therefore, clearing away fine pollutants on the quartz grain surface is an effective way to make silent sand emit audible sound.

关键词： booming sand, surface texture, quartz grain, sound-producing mechanism, Hemholz resonance cavity

Discussion on exploitation of mineral resources and ecological environmental issues in Wenquan, Wushan

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Acta Geochimica 2006年第S1期 44-45页

作者： Zhenming WEI1,2. Guodong ZHENG1,2. Yaling CHOU1,2.1 institute for Geological research, Chinese {2. of sciences, lanzhou 73000, china 2.State Key Laboratory of Frozen Soil engineering, cold and arid regions environmental and engineering research institute, Chinese {2. of sciences, lanzhou 73000, china

Temperature variation and its driving forces over the Antarctic coastal regions in the past 2.0 years

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Journal of Geographical sciences 2002年第4期12卷 379-386页

作者： ZHANG Mingjun1, 2. REN Jiawen2. CHENG Guodong2. LI Zhongqin2.XIAO Cunde2. QIN Dahe2. KANG Jiancheng3, LI Jun4(1. College of Geography and Environment, Northwest Normal University, lanzhou 730070, china 2. {2. and arid regions environmental and Eng College of Geography and Environment Northwest Normal University Lanzhou 730070 cold and arid {2. environmental and engineering research institute CAS Lanzhou 730000 Chinese institute of Polar research 上海 200129 Antarctic Cooperation research Center and Australian Antarctic Division 澳大利亚 Hobart

By comparing the oxygen isotopic temperatures recorded by many shallow ice cores from the coastal regions of Antarctica, this paper presents the special characteristics of the temperature variations over the Antarctic coastal regions in the past 50 years, 150 years and 2.0 years. In the past 50 years, the isotopic temperatures recorded in the ice cores over different sites on the Antarctic coastal regions differ greatly. For instance, although increasing isotopic temperatures have been reported for many sites studied, many sites show decreasing trends, the regional regularity in temperature variations is still insignificant. In the past 150 years, the isotopic temperature trends in the coastal regions of Antarctica show an alternate-distributing pattern. In the past 2.0 years, all the ice cores from the coastal regions of Antarctica have recorded the so-called Little Ice Age (LIA). The above-mentioned spatial characteristics of the temperature variations over the Antarctic coastal regions are likely to reflect the impacts of the unique Southern Hemisphere atmospheric circulation, the Antarctic Circumpolar Wave (ACW) and the special terrain (such as the large drainage basins) on the coastal regions of Antarctica. Furthermore, the impacting intensity of the unique Southern Hemisphere atmospheric circulation, the Antarctic Circumpolar Wave and the special terrain differs in terms of the temporal scale of the temperature change.

关键词： Antarctica ice core temperature terrain Antarctic Circumpolar Wave (ACW) circumpolar circulation

Using humic acid for remediation of sandy soils contaminated by heavy metal

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research in cold and {2. regions 2009年第3期1卷 267-276页

作者： YaJun Wang 1, HongLang Xiao 1, JinXi Wang 2. Yong Wang 3 1. Heihe Key Laboratory of Ecohydrology and River Basin Science, cold and arid {2. environmental and engineering research institute, Chinese academy of sciences, lanzhou, Gansu 730000, china. 2. School of Chemical engineering, Gansu Lian He University, lanzhou, Gansu 730000, china. 3. Yantai institute of Coastal Zone research for Sustainable Development,Chinese academy of sciences, Yantai, Shandong 2.4003, china. Heihe Key Laboratory of Ecohydrology and River Basin Science Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences School of Chemical engineering Gansu Lian He University

This paper presents the development of a new remediation technology for contaminated sandy soil using humic acid (HA). Distribution of amount of Cr (VI) in the aqueous or solid system containing humic acid and sandy soil, was studied using batch experiments, es-pecially for effects of reaction time, pH, concentrations, temperature and irradiation on the reduction of Cr (VI), and the optimum reaction conditions. The results indicated a significant increase of the adsorption of Cr (VI) because of the complexion reaction between HA and Cr (VI) that occurred under acidic condition. The reaction mechanisms of HA with chromium on sand surfaces were certified. Thus it came to a conclusion that HA could be used effectively on remediation of Cr (VI)–contaminated soil and groundwater in a wide range of pH, with or without sunlight. These results suggest that the organic-inorganic complex—such as sandy soils coated with humic substances—is important as a metal reservoir in the environment.

关键词： remediation humic acid hexavalent chromium complexion sandy soil

科尔沁沙地草地植被恢复演替进程中群落优势种群空间分布格局研究

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生态学杂志 2004年第2期23卷 1-6页

作者：张继义赵哈林中国科学院寒区旱区环境与工程研究所兰州730000

通过对处于流动沙地、半固定沙地和固定沙地等不同恢复演替阶段的群落的取样调查 ,研究了科尔沁沙地草地植被恢复进程中群落优势种群的空间分布格局及其动态变化。运用扩散系数、聚集指数、平均拥挤度、聚块性指数、Green指数、聚集强度... 详细信息

通过对处于流动沙地、半固定沙地和固定沙地等不同恢复演替阶段的群落的取样调查 ,研究了科尔沁沙地草地植被恢复进程中群落优势种群的空间分布格局及其动态变化。运用扩散系数、聚集指数、平均拥挤度、聚块性指数、Green指数、聚集强度、Poisson分布和负二项分布的 χ2.拟合检验等 7项指标 ,对群落优势种群的分布格局的研究结果基本一致 ,大多数物种的空间分布呈显著的聚集分布。在演替进程中种群格局强度的变化和群落总体聚集程度的变化与种群动态和群落结构的空间异质性相对应 ,较高的聚集程度是种群分布斑块化和群落结构的空间异质性的反映 ,随着演替进展 ,优势种的种群数量扩展 ,但种群分布的聚集强度下降 ,群落结构的空间异质性降低。在 7种测定分布格局的指标中 ,聚块性指数、Green指数和聚集强度是无量纲的指标 ,其大小不受种群大小的影响 ,其变化可以较好地指示格局强度本身的变化。

关键词：科尔沁沙地恢复演替草地群落空间格局

Reliability and Validity Test of Questionnaire on the Adaptation Strategy of Cryosphere Changes in arid Inland River Basin

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Meteorological and environmental research 2011年第4期2卷 1-4,8页

作者： WANG Ying-wei1, LIU Shou-dong1, DENG Mao-zhi2.3 1. School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 2.0044, china 2. cold and arid regions environmental and engineering research institute, Chinese {2. of sciences, lanzhou 730000, china 3. State Key Laboratory of Cryospheric sciences, Chinese {2. of sciences, lanzhou 730000, china

[Objective] The aim was to test the reliability and validity of questionnaire on the adaptation strategy of cryosphere changes in arid inland river basin. [Method] A questionnaire on 'the adaptation strategy of cryosphere changes in arid inland river basin' was carried out in Urumchi River basin and Aksu River basin, and its reliability and validity were tested by means of statistical method, so as to investigate the stability and accuracy of questionnaire. [Result] Reliability analysis of questionnaire showed that the split-half reliability coefficient of questionnaire in Urumchi River basin and Aksu River basin was 0.72. and 0.750, respectively, and Cronbach’s α reliability coefficient was 0.613 and 0.616, respectively, which revealed that the questionnaire had good equivalence and internal consistency which reflected good reliability and stability. According to validity analysis on questionnaire, there was significant correlation between the score of most questions and questionnaire, and it indicated that questionnaire had high content validity. There were 8 common factors collected from 2. questions, which were summarized as agricultural planting, agricultural water conservation, life satisfaction, cultivated land variation, social integration sense, climate and cryosphere changes, capital input improved by environment and family economic condition, respectively. Meanwhile, the contribution rate of various questions in corresponding indexes was higher, and reflected structure was in full accord with questionnaire content, which revealed that questionnaire owned good construct validity. [Conclusion] With higher stability and accuracy, the questionnaire could determine the desired topic and content and was suitable for the study on the perception of common people and choices of adaptive strategy under cryosphere changes in arid inland river basin in northwestern china.

关键词： Cryosphere changes Adaptive strategy Questionnaire Reliability and validity test china