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A land surface model incorporated with soil freeze/thaw and its application in GAME/Tibet

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science china Earth sciences 2006年第12期49卷 1311-1322页

作者： HU Heping1, YE Baisheng2, ZHOU Yuhua3 & TIAN Fuqiang1 1. Department of Hydraulic engineering, Tsinghua university, beijing 100084, china 2. Cold and Arid Regions environmental and engineering Research Institute, Chinese Academy of sciences, Lanzhou 730000, china 3. Department of civil engineering, Massachusetts Institute of technology, USA 1. Department of Hydraulic engineering Tsinghua University Beijing 100084 China 2. Cold and Arid Regions environmental and engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 3. Department of civil engineering Massachusetts Institute of Technology USA

Land surface process is of great importance in global climate change, moisture and heat exchange in the interface of the earth and atmosphere, human impacts on the environment and eco- system, etc. Soil freeze/thaw plays an important role in cold land surface processes. In this work the diurnal freeze/thaw effects on energy partition in the context of GAME/Tibet are studied. A sophisti- cated land surface model is developed, the particular aspect of which is its physical consideration of soil freeze/thaw and vapor flux. The simultaneous water and heat transfer soil sub-model not only reflects the water flow from unfrozen zone to frozen fringe in freezing/thawing soil, but also demon- strates the change of moisture and temperature field induced by vapor flux from high temperature zone to low temperature zone, which makes the model applicable for various circumstances. The modified Picard numerical method is employed to help with the water balance and convergence of the numerical scheme. Finally, the model is applied to analyze the diurnal energy and water cycle char- acteristics over the Tibetan Plateau using the Game/Tibet datasets observed in May and July of 1998. Heat and energy transfer simulation shows that: (i) There exists a negative feedback mechanism between soil freeze/thaw and soil temperature/ground heat flux; (ii) during freezing period all three heat fluxes do not vary apparently, in spite of the fact that the negative soil temperature is higher than that not considering soil freeze; (iii) during thawing period, ground heat flux increases, and sensible heat flux decreases, but latent heat flux does not change much; and (iv) during freezing period, soil temperature decreases, though ground heat flux increases.

关键词： land surface model,soil freeze/thaw,GAME/Tibet,simultaneous liquid,vapor and heat transfer.

INCIPIENT MOTION OF NON-COHESIVE SEDIMENT UNDER ICE COVER-AN EXPERIMENTAL STUDY

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Journal of Hydrodynamics 2008年第1期20卷 117-124页

作者： WANG Jun SUI Jue-yi KARNEY Bryan W. school of civil engineering Hefei University of Technology Hefei 230009 China environmental science and environmental engineering Program University of Northern British ColumbiaBritish Columbia Canada V2N 4Z9 Department of civil engineering University of Toronto Toronto Ontario Canada M5S 1A4

Based on a series of experiments under both ice-covered and free surface conditions, the present article discusses the role of flow velocity and critical shear Reynolds number for incipient motion of bed material. The influence of the resistance coefficients of both the underside of the ice cover and the channel bed on the location of the maximum velocity has been discussed. In addition, the impacts of ice and composite resistance coefficients on flow velocity for incipient motion of bed material have been assessed. The diagram describing the critical shear Reynolds number and the dimensionless shear stress for the incipient motion of sediment under ice covered conditions with different under cover resistance coefficient has been established. The effects of grain size on densimetric Froude number for incipient motion of bed material have been investigated. A relationship between the densimetric Froude number for incipient motion of bed material and the median grain size of bed material as well as the roughness coefficient of channel bed and roughness coefficient of ice cover has been established.

关键词： densimetric Froude number grain size ice cover incipient motion resistance coefficient shear Reynolds number,velocity

High-voltage transmission tower-line system subjected to disaster loads

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Progress in Natural science:Materials International 2006年第9期16卷 899-911页

作者： LI Hongnan and BAI Haifeng ( State Key Laboratory of Coastal and Offshore engineering, school of civil and Hydraulic engineering, Dalian university of technology, Dalian 116024, china china Railway No. 9 Group Co., Ltd., Shenyang 110013, china) [a]State Key Laboratory of Coastal and Offshore engineering School of Civil and Hydraulic Engineering Dalian University of Technology Dalian China [b]china Railway No.9 Group Co. Ltd. Shenyang China

The high-voltage power transmission system is an important lifeline structure. It is significant for wide researches on the features and ability of the system subjected to earthquake and environmental loads. The promising prosperity of the system has been demonstrated around the world. The corresponding advances of the system with respect to the mechanism of loading action, analytical methods, experimental research measurements, structural vibration control, fatigue damage, lifetime prediction, and design methods are comprehensively discussed herein. Finally, further research work on dynamic response characteristics of high-voltage transmission tower-line system in the near future is predicted.

关键词： high-voltage power transmission tower-line system loading effects dynamic analysis experimental researches design theories.

Degradation of Rhodamine B in aqueous solution by the UV/ZnO photocatalytic process

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Degradation of Rhodamine B in aqueous solution by the UV/ZnO...

In-situ Characterization of Non-aqueous Nano-dispersion Systems by Freeze-etching TEM and Comparative Study with Laser Scattering Method

2011 International Conference on Materials for Renewable Energy & Environment(ICMREE 2011)

作者： Jing Zhao Department of Materials Physics and Chemistry State Key Laboratory for Advanced Metals and Materials university of science and technology beijing chinaLi Wang school of civil&environmental engineering university of science and technology beijing beijing china

The photocatalytic degradation of rhodamine B（RB） was studied by using ZnO nanorods as the catalyst under UV light *** effect of the RB concentration and ZnO catalyst dosage were *** degradation rate reachs maximum when the pH value is about *** reuse of the as- grown ZnO catalysts has little effect on their photocatalytic activity.

关键词： nano-sized ZnO materials rhodamine B photocatalysis

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Journal of Wuhan university of technology(Materials science) 2010年第3期25卷 432-436页

作者：欧忠文 Department of Architecture and civil engineering Logistics Engineering University

In-situ characterization of non-aqueous nano-dispersion systems（NANDS） by freeze-etching transmission electron microscope（FETEM） was *** improve just-for-once successive rate of specimen preparation and get good characterization results,an improving specimen preparation method of freezing etching was ***,distribution and morphology of NANDS were directly *** information of particle dispersion feature and particle density can also be *** of the FETEM characterization is *** with laser scattering method,which is liable to give positive error especially for small size particle anchoring disperser,FETEM characterization can give more accurate measurement of particle ***,FETEM can give dispersion feature of nanoparticle in non-aqueous medium.

关键词： non-aqueous nano-dispersion system dispersion state in-situ characterization freeze-etching laser scattering method

Behavior Study on Safety Culture Construction of Coal Mine Enterprise

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Behavior Study on Safety Culture Construction of Coal Mine E...

FBG-based health monitoring for the secondary lining of Bainijing tunnel No.3 in Kunming,china

第三届教学管理与课程建设学术会议

作者： Zequan Lan 1 , Zhongan Jiang 2 1 Safety Training Department North china Institute of science and technology beijing, china,101601 12 civil and environmental engineering Institute university of science and technology beijing beijing, china, 100083

On the basis of analyzing the main problems existing in coal mine enterprise, some corresponding countermeasures are presented on how to carry out safety culture construction, in accordance with behavioral science theory, convergence theory and principle of safety culture force field. Namely, safety culture construction mode of three different levels including individual behavior, group behavior and organization behavior are carried forward, thus forming a good atmosphere that everybody values safety and resultant force of doing safety production well together. Through strengthening of safety value concept and safety conduct code, employee’s safety quality will improve constantly. Consequently, intrinsic safety level and ability to prevent accident will promote in coal mine enterprise.

关键词： safety culture individual behavior group behavior organizational behavior

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FBG-based health monitoring for the secondary lining of Bain...

SEEPAGE ABILITY OF HIGH-PRESSURE HOT COMPOSITE FOAM IN POROUS MEDIA

The International Young Scholars’ Symposium on Rock Mechanics

作者： X.G.Zhao school of civil and environmental engineering university of science and technology beijing beijing china & Geomechancis Research Centre Laurentian university Sudbury Canada H.T.Qiu school of civil and environmental engineering university of science and technology Beifing beijing china C.Li J.P.Liu College of information engineering and Automation Kunming university of science and technology Kunming china.

＜正＞The fiber bragg grating（FBG）sensor is a newly developed monitoring *** monitoring using FBG sensing technology has been carried out at the Bainijing tunnel No.3 located in Kunming, *** principle and advantages of FBG sensingr technology are briefly introduced,and the installation scheme of FBG sensors is put forward according to the results of numerical simulation for the secondary lining of the *** order to solve the problem that the Bragg wavelength shift is simultaneously sensitive to strain and temperature,a temperature compensation method is *** to eleven months strain the results of strain monitoring during monitoring results,the key factor resulting in increase of strain in the secondary lining of the tunnel is ***,the characteristics of strain and rainfall variations with time are analyzed, and the health diagnose of the tunnel is *** results show that the FBG sensing technology can reveal the distribution of strain and diagnose health status of tunnels.

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Journal of Hydrodynamics 2010年第1期22卷 90-95页

作者： WANG Ke-liang LIANGShou-cheng YUAN Xin-qiang CHEN Jin-feng The Key Laboratory of Enhanced Oil and Gas Recovery of the Ministry of Education Daqing Petroleum Institute Daqing 163318 China College of civil and environmental engineering University of Science and Technology Beijing Beijing 100083 China The Second Oil Production Company of Daqing Oilfield Company Ltd. Daqing 163414 China

The technology of hot composite foam displacement refers to the injection of high-temperature flue gas and foaming and stabilizing agent into wells with a certain concentration, and after meeting the formation water, a composite foam system is formed in the reservoir. This foam displacement technology involves thermal function and so is related to nitrogen, carbon dioxide and foam flooding characteristics. After analyzing seepage flow law of hot composite foam system, seepage flow experiment of composite foam under high pressure was conducted, and seepage flow ability of hot composite foam in porous media was investigated. In the experiment, surfactant HY-3 was chosen as the foaming agent and hot flue gas was chosen as the foaming gas, and high-pressure hot foaming apparatus was employed in experiments. The experimental results indicate that the surfactant HY-3 could form stable foam in porous media, and the foam has strong ability of plugging. It is concluded that the sealing performance of foam is improved with increasing permeability and resistance coefficient and with incresing injection rate and foam strength. After foam injection, sealing characteristics of heterogeneous cores is better than that of homogeneous cores. The foam pressure has a process of transmission in porous media. In this process, with the increase of injection volume, pressure from the inlet to the outlet increases gradually, which indicates that stable foam has been formed inside the core.

关键词： composite foam surfactant HY-3 seepage flow under high pressure porous media

Characterizing the Mass Elevation Effect across the Tibetan Plateau

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Journal of Mountain science 2018年第12期15卷 2651-2665页

作者： HAN Fang ZHANG Bai-ping ZHAO Fang WAN Li TAN Jing LIANG Tian school of civil and Architectural engineering, Shandong university of technology Institute of Geographic sciences and Natural Resources Research, State Key Laboratory of Resources and environmental Information System, Chinese Academy of sciences College of Environment and Planning, Henan university Chinese Research Academy of environmental sciences beijing Aerospace TITAN technology Co., Ltd school of civil and Architectural engineering Shandong University of TechnologyZibo 255000China Institute of Geographic sciences and Natural Resources Research State Key Laboratory of Resources and Environmental Information SystemChinese Academy of SciencesBeijing 100101China College of Environment and Planning Henan UniversityKaifeng 455000China Chinese Research Academy of environmental sciences Beijing 100012China beijing Aerospace TITAN technology Co. LtdBelling 100083China

It is over 110 years since the term Mass Elevation Effect(MEE) was proposed by A. D. Quervain in 1904. The quantitative study of MEE has been explored in the Tibetan Plateau in recent years; however, the spatial distribution of MEE and its impact on the ecological pattern of the plateau are seldom known. In this study, we used a new method to estimate MEE in different regions of the plateau, and, then analyzed the distribution pattern of MEE, and the relationships among MEE, climate, and the altitudinal distribution of timberlines and snowlines in the Plateau. The main results are as follows:(1) The spatial distribution of MEE in the Tibetan Plateau roughly takes on an eccentric ellipse in northwestsoutheast trend. The Chang Tang Plateau and the middle part of the Kunlun Mountains are the core area of MEE, where occurs the highest MEE of above 11℃; and MEE tends to decreases from this core area northwestward, northeastward and southward;(2) The distance away from the core zone of the plateau is also a very important factor for MEE magnitude, because MEE is obviously higher in the interior than in the exterior of the plateau even with similar mountain base elevation(MBE).(3) The impacts of MEE on the altitudinal distribution of timberlines and snowlines are similar, i.e., the higher the MEE, the higher timberlines and snowlines. The highest timberline(4600–4800 m) appears in the lakes and basins north of the Himalayas and in the upper and middle reach valleys of the Yarlung Zangbo River, where the estimated MEE is 10.2822℃–10.6904℃. The highest snowline(6000–6200 m) occurs in the southwest of the Chang Tang Plateau, where the estimated MEE is 11.2059°C–11.5488℃.

关键词： Mass Elevation Effect (MEE) Distribution Pattern Timberline Snowline Tibetan Plateau