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Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

Science china(Technological Sciences) 2004年第z1期47卷 1-13页

作者： YANG Shengtian1.& LIU Changming1. 2.1. School of Environmental Sciences, {1. Normal University, {1. 1.0875,{2. 2. institute of Geographic Science and Natural Resources Research, {1. 1.01.1.{2. beijing Normal Univ Sch Environm Sci Beijing 100875 Peoples R China Inst Geog Sci & Nat Resources Beijing 100101 Peoples R China

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1.82.1.98, soil moisture of all layers of soil-profile (0—1.m) in the Yellow River basin over the 1. years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1.82.to 1.88 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4000 km3, the evapotranspiration of 3000-3500 km3, and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 1. years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

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Three industries and wastewater and COD discharge of beijing

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Journal of Environmental Sciences 2000年第4期12卷 474-477页

作者： WANG Yan 1. WANG Hong rui 2. NING Da tong 2.(1. beijing Municipal Research {1. of Environmental Protection, beijing 1.0037, china 2. {1. of Environmental Sciences, beijing Normal University, beijing 1.0875, china) 北京市环境保护所北京 1 0 0 0 3 北京师范大学北京 1 0 0 875

With the swift development of economy, the water quality of beijing is becoming worse day by day and hampers the sustainable development obviously. In this paper, the current conditions of the municipal wastewater structure in the industrial sectors are analysed and discussed in terms of the indicators, such as direct wastewater\|discharge coefficient, complete wastewater\|discharge coefficient, direct discharge coefficient of COD and complete discharge coefficient of COD, by taking a year of 1.90s as the base year. Some countermeasures are studied and the corresponding recommendations are put forward in order to improve the water environment in beijing. This provides a scientific ground for coordinating the relationship between the aquatic environment and economic growth in this city.

关键词： direct wastewater discharge coefficient (DWDC) complete wastewater discharge coefficient (CWDC) direct discharge coefficient of COD(DDC of COD) complete discharge coefficient of COD (CDC of COD)

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Research progress in synthesis and catalysis of polyoxometalates

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Progress in Natural Science:Materials International 2005年第5期15卷 385-394页

作者： GONG Yun1. HU Changwen1.* and LIANG Hong2.1. Department of Chemistry, School of Science, the {1. for Chemical Physics, {1. {1. of Technology, {1. 1.0081. china 2. Chemical Industry Press, {1. 1.002., china) Department of Chemistry School of Science the Institute for Chemical Physics Beijing Institute of Technology Beijing 100081 China Chemical Industry Press Beijing 100029 China

Recent progress in the synthetic chemistry and catalysis of polyoxometalates (POMs) is reviewed. The novel POMs and their derivatives emerging in nearly three years (2.02.2.04) are introduced, including POMs with novel structure, POMs-organic hybrid compounds and host-guest complexes. Our review is focused on the elaboration of POMs' supramolecular chemistry.

关键词： polyoxometalates hybrid host-guest structure supramolecule catalysis.

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Distribution and characteristics of gravelly soil liquefaction in the Wenchuan M_s 8.0 earthquake

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 167-175页

作者： Cao Zhenzhong1.Hou Longqing2.Xu Hongmei2.and Yuan Xiaoming1.1. institute of Engineering {1.,{2. Earthquake Administration,Harbin 1.0080,{2. 2. East china institute of Technology,Fuzhou 344000,{2. institute of Engineering {1. China Earthquake Administration Harbin 150080 China

In this paper,a distribution map of gravelly soil liquefaction that was caused by the Wenchuan M8.0 earthquake in china is proposed based on a detailed field investigation and an analysis of geological soil profiles. The geological background of the earthquake disaster region is summarized by compiling geological cross sections and borehole logs. Meanwhile,four typical liquefied sites were selected to conduct sample drillings,dynamic penetration tests (DPT),and shear wave velocity tests,to understand the features of liquefied gravelly soil. One hundred and eighteen (1.8) liquefied sites were investigated shortly after the earthquake. The field investigation showed:(1. sandboils and waterspouts occurred extensively,involving thousands of miles of farmland,1.1. villages,eight schools and five factories,which caused damage to some rural houses,schools,manufacturing facilities and wells,etc.; ({1. the Chengdu plain is covered by a gravelly soil layer with a thickness of 0 m to 541.m according to the geological cross sections; (3) there were 80 gravelly soil liquefied sites in the Chengdu plain,shaped as five belt areas that varied from {1. km to 40 km in length,and about ten gravelly soil liquefied sites distributed within Mianyang area; and (4) the grain sizes of the sampled soil were relative larger than the ejected soil on the ground,thus the type of liquefied soil cannot be determined by the ejected soil. The gravelly soil liquefied sites are helpful in enriching the global database of gravelly soil liquefaction and developing a corresponding evaluation method in further research efforts.

关键词： gravelly soil liquefaction borehole soil profile geological cross section grain size distribution Wenchuan earthquake

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On three-dimensional geological modeling and visualization

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Science china Earth Sciences 2004年第8期47卷 739-748页

作者： WU Qiang1.& XU Hua2.1. Department of Resource Exploitation Engineering,{1. University of Mining and Technology, {1. 1.0083,{1. 2. {1. institute of Petrochemical Technology, {1. 1.2.1.,{1. 1. Department of Resource Exploitation Engineering China University of Mining and Technology 100083 Beijing China 2. {1. {1. of Petrochemical Technology 102617 Beijing China

The technology of 3D geological modeling will bring about great changes in the methods of geological data acquiring, storing, processing and displaying. However, no perfect or convenient software systems have been developed up to now since the geologic data which re-flect geological entities bear the feature of diversity, uncertainty and complexity. Some supervoxel models, mathematical models of fault and geometrical models of fold have been contrived so as to show the space geometric configuration of the complicated geologic structures. The application-oriented system architecture for 3D geological modeling is established; and a novel design concept based on spatial data processing is also proposed with the technology of solid modeling as its core and the application of models as its objective. Theories and methods for 3D geological modeling will hopefully be enriched and developed. In the light of these theories and methods, a feature-based navigation visualization technique is also put forward in the paper. By integrating geo-database, graphics libraries and KBS with 3D dynamic simulation systems, geologists will be able to capture the partial characteristics and whole structure embodied in the geological data in a direct-viewing, figurative and accurate manner.

关键词： 3D geological modeling,geometrical model,system architecture,visualization

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A circum-earth shear zone at low-latitudes and episodic large earthquakes in it and the circum-Pacific seismic zone

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Science china Earth Sciences 2006年第9期49卷 897-903页

作者： MA Zongjin1. DU Pinren1. REN Jinwei2.& GAO Xianglin1.1. {1. of Geology,{1. Earthquake Administration, {2. 1.002.,{1. 2. {1. of Earthquake Science,{1. Earthquake Administration, {2. 1.0036,{1. 1. institute of Geology China Earthquake Administration Beijing 100029 China 2. {1. of Earthquake Science China Earthquake Administration Beijing 100036 China

Because of the differential motions between the Northern and Southern Hemispheres of the Earth, there exists a motion discordant zone between them. On the surface this zone consists of 1. large faults dominant with strike-slip. We call it a global shear zone at low-latitudes (E system). By statistical analysis of temporal distribution of earthquakes Mw≥7.5 in the E system and the circum-Pacific (P system) during 1.00―2.03, we find that there exist quasi-episodic and alternative activities in and between these two systems. This phenomenon is likely associated with the half-sphere oscillation in dilation and contraction and the change of the Earth’s rotation rate.

关键词： shear zone, circum-Pacific zone, great earthquake, quasi-episode.

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A mathematical model for solid liquid and mass transfer coupling and numerical simulation for hydraulic fracture in rock salt

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Progress in Natural Science:Materials International 2005年第8期15卷 742-748页

作者： LIANG Weiguo 1.2. and ZHAO Yangsheng1.1. Mining Technology {1., Taiyuan University of Technology, Taiyuan 03002.,{1. 2. Rock and Soil {2. {1., Chinese Academy of Sciences, Wuhan 430071.{1.) Mining Technology institute Taiyuan University of Technology Taiyuan 030024 China. Rock and Soil mechanics {1. Chinese Academy of Sciences Wuhan 43007! China

The hydraulic fracture in rock salt is a complicated solid fluid and mass transfer coupling process. Through theoretical analysis, a solid fluid and mass transfer coupling mathematical model of hydraulic fracture in rock salt is established in this work, and numerical simulations are carried out with the model. The simulation results indicate that rock salt cracks in the typical way of wing-crack(or tensile crack) during the fracture, and the relation of fracture aperture (w) with expanding distance (x) and fracture time (t) is w=(0.0034+0.0006t)e (0.0007+0.001.t)x. Furthermore, it has been found that both the water pressure in the crack and the expanding velocity of the crack decrease gradually as a result of the influence of salt dissolving during fracturing. These numerical simulations well illustrate the process of hydraulic fracture in rock salt and are significantly meaningful in engineering practice.

关键词： rock salt hydraulic fracture solid liquid and mass transfer coupling mathematical model numerical simulation.

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Experimental EOS determination of aluminum at Mbar pressure

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Science china(Physics,{1. & Astronomy) 2004年第4期47卷 416-423页

作者： CHEN Jianping1.2. LI Ruxin1. ZENG Zhinan1. WANG Xingtao1.& XU Zhizhan1.1. Shanghai {1. of Optics and Fine {1., Shanghai 2.1.00,{2. 2. beijing Aeronautical Technology Research Center, beijing 1.0076,{2. 1. Shanghai institute of Optics and Fine {1. 201800 Shanghai China 2. {1. Aeronautical Technology Research Center 100076 Beijing China

A shock wave is driven by a laser pulse of 1.2.ps duration (FWHM), with the intensity of ～1.1. W/cm2.at 785 nm, irradiating a 500 nm thick aluminum foil. A chirped laser pulse split from the main pulse is used to detect the shock breakout process at the rear surface of the target based on frequency domain interferometry. The mean shock velocity determination benefits from the precise synchronization (＜1.0fs resolution) of the shock pump and probe laser pulses, which is calculated from the time the shock takes to travel the 500 nm thick aluminum. The released particle velocity determination benefits from the chirped pulse frequency domain interferometry. The average shock velocity is 1..1. km/s and the shock release particle velocity is 1..2. km/s, and the corresponding pressure after shock is 3.1.0}Mbar under our experimental condition.

关键词： shock wave, equation of state, chirped laser pulse.

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Study of the circulation theory of the cooling system in vertical evaporative cooling generator

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Science china(Technological Sciences) 2006年第3期49卷 358-364页

作者： YU Shunzhou1. CAI Jing2. GUO Chaohong1.& GU Guobiao1.1. {1. of Electrical Engineering, Chinese Academy of Sciences,{1.,{2. 2. beijing Changcheng {1. of Metrology and Measurement, beijing 1.0095,{2. institute of Electrical Engineering Chinese Academy of Sciences Beijing 100080 China beijing Changcheng {1. of Metrology Measurement Beijing 100095 China

The article briefly states the current development of evaporative cooling generator; its advantages comparing with generators of traditional cooling. Vertical evaporative cooling generator, which adopts Close-Loop-Self-Cycle with no-pump; free convection boil in the hollow stator bar, is one of the great developments in generator design. This article emphasizes the importance of cooling system in generator; expatiates the circulation theory in two aspects, energy; flow;; analyzes the essential reason, motivity; stability of Close-Loop-Self-Cycle. The article points out that the motivity of the circulation is the heat absorbed by coolant. After absorbing heat the coolant will have the ability of doing work because of the phase change. In another words, it is the buoyancy causing by density difference leads to the Close-Loop-Self-Cycle. This conclusion is validated by experimental data.

关键词： vertical evaporative cooling generator, cooling system, circulation theory.

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Gasdynamic characteristics of toroidal shock and detonation wave converging

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Science china(Physics,{1. & Astronomy) 2005年第6期48卷 739-749页

作者： TENG Honghui1.2.& JIANG Zonglin2.1. Key Laboratory of High Temperature Gas Dynamics, institute of {1., Chinese Academy of Sci- ences,{2., china 2. Graduate University of Chinese Academy of Sciences, beijing 1.0039, china 1. Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences 100080 Beijing China 2. Graduate University of Chinese Academy of Sciences 100039 Beijing China

The modified CCW relation is applied to analyzing the shock, detonation wave converging and the role of chemical reactions in the process. Results indicate that the shock wave is strengthened faster than the detonation wave in the converging at the same initial Mach number. Euler equations implemented with a detailed chemical reaction model are solved to simulate toroidal shock and detonation wave converging. Gasdynamic characteristics of the converging are investigated, including wave interaction patterns, observable discrepancies and physical phenomena behind them. By comparing wave diffractions, converging processes and pressure evolutions in the focusing area, the different effects of chemical reactions on diffracting and converging processes are discussed and the analytic conclusion is demonstrated through the observation of numerical simulations.

关键词： converging, CCW relation, shock wave, detonation wave.

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