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Simulation of energy and water balance in soil-Vegetation-Atmosphere Transfer system in the mountain area of Heihe River Basin at Hexi Corridor of northwest china

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Science china Earth sciences 2005年第4期48卷 538-548页

作者： KANG Ersi1, CHENG Guodong1, , SONG Kechao1, JIN Bowen1, , LIU Xiande3.2 3.& WANG Jinye3.1. Cold and Arid Regions Environmental and Engineering Research Institute, chinese academy of sciences, lanzhou 730000, china 2. {3. key laboratory of frozen soil Engineering, chinese academy of sciences, lanzhou 730000, china 3. academy of Water Resources Conservation Forest of Qilian Mountains, Gansu Province, Zhangye 73.000, china Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China state key laboratory of {3. nsoil Engineering Chinese Academy of Sciences Lanzhou China academy of Water Resources Conservation Forest of Qilian Mountains Gansu Province Zhangye China

In the mountain area of inland Heihe River Basin at Hexi Corridor of northwest china during the vegetation growing season from May to September, the Simultaneous Heat and Water (SHAW) model of soil-Vegetation-Atmosphere Transfer (SVAT) system is applied to simulating and studying energy and water balance of the soil-residue-plant canopy layers in the Picea crassifolia forest and the grassland by the forest at the shaded slope and the grassland at the sun-facing slope. The simulation of energy balance indicates that net radiation of the grass- land at the sun-facing slope is more than that of the Picea crassifolia forest and the grassland by the forest at the shaded slope. The energy outgoing components are the first latent heat and next sensible heat from the grassland both at the shaded slope and the sun-facing slope, but those at the former are less. The energy outgoing components are the first sensible heat and next latent heat from the Picea crassifolia forest. The composition and distribution of energy in the soil-residue-plant canopy layers in the Picea crassifolia forest and the grassland by the forest at the shaded slope make the soil layer receive less energy, which therefore, especially the forest possesses the energy conditions for soil water conservation. The simulation of water balance indicates that the water loss of the grassland at the sun-facing slope is mainly caused by soil evaporation, while evapotranspiration of the Picea crassifolia forest and the grassland by the forest at the shaded slope is less than that of the grassland at the sun-facing slope. Half of the evapotranspiration of the Picea crassifolia forest and the grassland by the forest at the shaded slope is consumed by transpiration. After precipitation, the soil water storage is increased much more for the Picea crassifolia forest and also more for the grassland by the forest at the shaded slope. Therefore the shaded slope vegetation, especially the forest is favorable for soil water s

关键词： inland rivers, mountain vegetation zone, soil-Vegetation-Atmosphere Transfer (SVAT) system, energyand water balance, simulation.

Dynamic calculation model and seismic response for frame supporting structure with prestressed anchors

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Science china(Technological sciences) 2010年第7期53卷 1957-1966页

作者： DONG JianHua1’2, ZHU YanPeng1, ZHOU Yong1 & MA Wei2 1 College of Civil Engineering, lanzhou University of Technology, lanzhou 73.050, china 2 {3. key laboratory of frozen soil Engineering, Cold and Arid Regions Environmental and Engineering Research Institute, chinese academy of sciences, lanzhou 730000, china College of Civil Engineering Lanzhou University of Technology Lanzhou China state key laboratory of {3. soil Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

A dynamic calculation model of frame supporting structures with prestressed anchors for the slope stability is proposed. The frame and soil are closely contacted in the role of prestressed anchors and they cannot be separated along the whole slope. The lateral displacement of frame and soil is nearly in phase. The movement characteristic satisfies the theory of elastic foundation beam. The frame is treated with elastic foundation beam in this model. The influence of prestressed anchors is simplified as linear spring and damped system related with velocity. Under the condition of horizontal earthquake excitation, the equation of vibration response is established by using the model of dynamic Winkler beam and the analytical solutions are obtained for simple harmonic vibration. This method is applied to a case record for illustration of its capability, in order to verify the method, 3. nonlinear FEM (ADINA) is used to analyze the seismic performance of this case, the comparative results show that the design and the analysis are safe and credible by using the proposed method. The calculation model provides a new way for earthquake analysis and seismic design of slope stability supported by frame structure with prestressed anchors.

关键词： frame supporting structure with prestressed anchor slope dynamic calculation model seismic performance seismic design

The consideration and choice on exploiting energy source

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chinese Science Bulletin 1999年第18期44卷 1717-1728页

作者： WANG Xianbinstate key laboratory of Gas Geochemistry, {3. Institute of Geology, chinese academy of sciences , lanzhou 730000, china state key laboratory of Gas Geochemistry Lanzhou Institute of Geology Chinese Academy of Sciences Lanxhou China

A problem of petroleum energy crisis will probably be faced in the late 21st century. It is impossible to discover the giant oil fields again based on the traditional knowledge and theory of petroleum geology. From the global development point of view as well as the situation in china, the five choices of energy source in the future are to ( i ) extend the field of exploration in conventional petroleum and natural gas source, and exploit oil-gas source in ocean and

关键词： energy sources in the future unconventional gas coal hydrogen controllable nuclear fusion 3.e source on the moon.

Effects of chlorothalonil and carbendazim on nitrification and denitrification in soils

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Journal of Environmental sciences 2009年第4期21卷 458-467页

作者： LANG Man, CAI Zucong state key laboratory of {3. and Sustainable Agriculture, Institute of {3. Science, chinese academy of sciences,Nanjing 210008, china state key laboratory of {3. and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China

The effects of chlorothalonil and carbendazim on nitrification and denitrification in six soils in upland and rice paddy environments were investigated. laboratory aerobic （60% water holding capacity） and anaerobic （flooded） conditions were studied at 25℃ and fungicide addition rates of 5.5 mg/kg A. I. （field rate, FR）, 20 times （20FR） and 40 times （40FR） field rate, respectively. The results indicated that chlorothalonil at the field rate had a slight inhibitory effect on one soil only, and that soil did not nitrify much in the first place. But chlorothalonil at higher rates inhibited nitrification significantly in all soils. For soils JXP and JXU with a pH of less than 5.0, chlorothalonil almost completely stopped their nitrification at 20FR and 40FR during the whole 14 d incubation period. For soils HNP and HNU with a pH of greater than 8.0, chlorothalonil also significantly inhibit nitrification at 20FR and 40FR （p 〈 0.05）. However, NH4＋ that was added to the soil was also almost completely nitrified by the end of the incubation period in these two soils. The effects of chlorothalonil at 20FR and 40FR on the nitrification of JSP and JSU soils, with a pH of 5.4 and 7.2, respectively, were intermediate between the other soil types. Chlorothalonil had no effect on denitrification at the field rate and had little effect at the higher rates of application in some soils. Carbendazim had essentially no effect on nitrification and denitrification in soils assessed.

关键词： fungicide nitrification denitrification chlorothalonil carbendazim

Characterization and Tribological Behavior of Octadecene,Dodecene and Undecenoic Acid Films on Si Substrate

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Journal of Materials Science & Technology 2005年第5期21卷 671-674页

作者： Jinfang ZHOU+ and Shengrong YANGstate key laboratory of Solid Lubrication, {3. Institute of Chemical Physics, chinese academy of sciences, {3.730000, china state key laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

The films of octadecene, dodecene, and undecenoic acid were prepared on H-terminated Si surface in the presence of ultraviolet irradiation. The resulted films were characterized with water-contact angle measurement and infrared spectroscopy. The friction-reducing behavior of the prepared films was examined on a static-dynamic friction coefficient measurement apparatus and on an atomic force microscope. It was found that all the reacted films on the Si substrate showed good friction-reducing ability; especially, the film of the octadecene exhibited the best friction-reducing ability. This was attributed to the transfer of the reacted films onto the counter face with formation of a transfer film on the counterpart surface, which led to the transformation of the sliding between the reacted films and the hard ceramic to fiat between the reacted films and its transfer film on the counterpart surface. The macroscopic and microscopic friction behaviors of the prepared films were dependent on their molecular chain lengths. Thus the octadecene reacted film with the highest degree of ordering arrangement showed the best friction-reducing and antiwear abilities in sliding against Si3.4.

关键词： Alkese Reaction film Hydrogen-terminated silicon Tribological behavior

Heat transfer process of roadway embankments with different type and width of road surface in permafrost regions

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Progress in Natural Science:Materials International 2007年第3期17卷 314-319页

作者： YU Qihao, PAN Xicai, CHENG Guodong and BAI Yang (state key laboratory of {3. soil Engineering, Cold and Arid Regions Environment and Engineering Research Institute, chinese A-cademy of sciences, lanzhou 730000, china) state key laboratory of {3. soil Engineering Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

The stability of roadbed in permafrost areas has become a big concern with rapid development and construction of throughways, highways and railways in these areas under the current climate change since it is governed by the thermal condition, or in other words, the heat transfer process in the embankment. We carried out a finite element analysis to analyze the effects of different types of road surface and the effect of breadth of embankment on the embankment heat transfer process. The results indicated that the mean annual heat transfer rate at the bottom of the roadway embankment with asphalt surfaces is 3.times that with sandy gravel surfaces. This means annual heat transfer rate increased by 60% when the breadth of asphalt surface was doubled. The increased heat transfer rate was mainly located at the bottom of the embankment and resulted in the effect of thermal concentration,. leading to degradation of the permafrost by as much as 1.6 times. It was also found that increasing embankment height would not reduce these increases of the heat transfer rate. Therefore both asphalt road surface and increased embankment breadth can lead to an intensified heat transfer rate in roadway embankment, consequently degradating the underlying permafrost and embankment instability.

关键词： wide road surface roadway embankment permafrost regions process of heat transfer heat flux ground temperature field.

Asymmetric Catalytic Hydrogenation Using Rhodium Diphosphinites Derived From D-glucose and D-mannitol

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chinese Chemical Letters 2000年第7期11卷 587-588页

作者： Peng JIANG Shi Jie LU(state key laboratory of Oxo Synthesis and Selective Oxidation, {3. Institute of Chemical Physics, chinese academy of sciences, lanzhou 730000) state key Lab. Oxo Synthesis S. Lanzhou Inst. of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

Three diphosphinites were synthesized for preparing rhodium-diphosphinite complexes. The complexes were used for asymmetric catalytic hydrogenation of amino acid precursor alpha-acetamidocinnamic acid and its methyl e... 详细信息

关键词： asymmetric catalysis hydrogenation rhodium diphosphinites alpha-acetamidocinnic acid

Three Novel Eremophilanolides from Ligularia virgaurea ***

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chinese Chemical Letters 2004年第12期15卷 1441-1444页

作者： Quan Xiang WU Yan Ping SHI Li YANG state key laboratory of Applied Organic Chemistry, {3. University, lanzhou 730000 {3. Institute of Chemical Physics chinese academy of sciences (CAS) {3. 730000 state key Lab. of Appl. Organ. Chem. Lanzhou University Lanzhou 730000 China lanzhou Inst. of Chemical Physics Chinese Academy of Sciences (CAS) Lanzhou 730000 China

From the alcoholic extract of the whole plant of Ligularia virgaurea spp. oligocephala,three novel eremophilane sesquiterpene lactones, 6α, 10α-dihydroxy-1-oxoeremophila- 7(11),8(9)-dien-8, 12-olide, 6β, 10α-dihydroxy-1-oxoeremophila-7 (11), 8 (9)-dien-8, 12-olide and10α-diydroxy-1-oxoeremophila-7(11), 8 (9)-dien-8, 12 olide were isolated. Their structure s wereelucidated by various, spectroscopic methods including intensive 2D NMR techniques (COSY,HMQC, HMBC and ~1H-~1H NOESY) and HR-MS.

关键词： Ligularia virgaurea spp oligocephala Compositae sesquiterpene lactones eremophilanolides.

CORRECTION METHODS FOR STEADY INCOMPRESSIBLE FLOWS

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Journal of Computational Mathematics 1999年第4期17卷 419-424页

作者： Jian Li(state key laboratory of Scientific and Engineering Computing, ICMSEC,{3., Beijing 100080, china) 中科院计算数学与科学工程计算所科学与工程计算国家重点实验室北京

Correction methods for the steady semi-periodic motion of incompressible fluid are investigated. The idea is similar to the influence matrix to solve the lack of vorticity boundary conditions. For any given boundary condition of the vorticity, the coupled vorticity-stream function formulation is solved. Then solve the governing equations with the correction boundary conditions to improve the solution. These equations are numerically solved by Fourier series truncation and finite difference method. The two numerical techniques are employed to treat the non-linear terms. The first method for small Reynolds number R equals 0-50 has the same results as that in M. Anwar and S.C.R. Dennis' report. The second one for R greater than 50 obtains the reliable results. (Author abstract) 4 Refs.

关键词： incompressible flow vorticity stream function numerical solution