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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 73.000,{3. 2. State Key Laboratory of Frozen Soil engineering, Chinese Academy of Sciences, Lanzhou 73.000,{3. 3. Academy of Water Resources Conservation Forest of Qilian Mountains, Gansu Province, Zhangye 73.000,{3. 1. Cold and Arid Regions Environmental and engineering research institute Chinese Academy of Sciences 730000 Lanzhou China 2. State Key Laboratory of Frozen nSoil engineering Chinese Academy of Sciences 730000 Lanzhou China 3. Academy of Water Resources Conservation Forest of Qilian Mountains 734000 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.

the optical near-field speckles and their first order statistics on the basis of the integral equations of electromagnetic field

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Science china(Physics,Mechanics & Astronomy) 2004年第3期47卷 365-380页

作者： CHENG Chuanfu1, 2, SONG Hongsheng2, LIU Chunxiang2, REN Xiaorong2, ZHANG Ningyu3. TENG Shuyun1 & XU Zhizhan1 1. Shanghai institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P. O. Box 800-211, Shanghai 201800, china 2. Department of Physics, Shandong Normal University, Jinan 250014, china 3. Shandong institute of Architecture and engineering, Jinan 250014, china 1. Shanghai institute of Optics and Fine Mechanics Chinese Academy of Sciences P. O. Box 800-211 201800 Shanghai China 2. Department of Physics Shandong Normal University 250014 Jinan China 3. Shandong institute of Architecture and engineering 250014 Jinan China

From Helmholtz equation of the harmonic electromagnetic waves, the integral equations of the light field at the medium boundaries are obtained by use of the Green's theorem and are discretized into linear equation set with the values of the light field and its derivative as the unknowns. On solving the linear equation set, we realize the rigorous computations of the light fields at the boundaries. then the intensities of the light waves scattered by the random self-affine fractal surfaces in the optical near-field are calculated, and the propagation characteristics, the evolutions of the contrast and the intensity probability density function of the near-field speckles are studied in detail. the near-field speckles are much different from the conventional speckles in the diffraction regions and in the imaging systems. there are obvious local fluctuations in the intensity distributions of the near-field speckles and such fluctuations disappear after propagating a distance of one wavelength from the medium surfaces. For the random surfaces with smaller lateral correlation lengths, the speckle contrasts approach the saturation values and the speckle fields approach Gaussian distribution within the near-field, while for the random surfaces with larger lateral correlation lengths, such evolutions become comparatively slow.

关键词： speckle, near-field optics, first order statistics, Green's function.

PLANE STRESS DYNAMIC FIELDS NEAR A PROPAGATING CRACK-TIP IN A POWER-LAW MATERIAL

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Acta Mechanica Sinica 1988年第1期4卷 22-34页

作者： Zhang Zimao Gao Yuchen Harbin shipbuilding engineering institute, Harbin.{3. Now at Department of Mechanics, Harbin institute of Technology, Harbin,{3.. 1. Harbin shipbuilding engineering institute Harbon China

Based on the plastic-dynamic equations, the asymptotic behaviour of the near-tip fieldsfor a plane stress tensile crack propagating in a power-law material has been studied in this paper, It isshown that the stress and strain singularities are, respectively, of the order (In A/r)~(1/(n-1)) and(In A/r)~(n/(n-1)).where A is a constant which is related to the size of plastic region, r is the distance to the crack tip, n isthe power-law exponent.

关键词： power-law material strain singularity singularity-factor elastic region plasticregion.

EXPERIMENTAL STUDY OF ROCK BREAKING EFFECT OF STEEL PARTICLES

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Journal of Hydrodynamics 2011年第2期23卷 241-246页

作者： CUI Meng ZHAI Ying-hu JI Guo-dong MOE Key Laboratory of Petroleum engineering China University of Petroleum Beijing 102249 China CNPC Drilling research institute Beijing 100195 China

Particle impact drilling is an efficient drilling technology for deep-well hard formation, With this technology, the rock is cut mainly by high-speed spherical particle impact under hydraulic action. In this article, the influence of jet flow factors, hydraulic factors and abrasive factors on rock breaking is studied through indoor experiments of impact by steel particles. the results indicate that the particle water jet has an optimal standoff distance and particle concentration; the rock breaking effect declines with the increase of the confining pressure and the decrease of the pump pressure and particle diameter. this study will provide some food of thought for the development of particle impact drilling technology.

关键词： hard formation particle impact drilling water jet rock breaking effect experimental research

An improved approach to the efficient construction of and search operations in motion graphs

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Science china(Information Sciences) 2012年第5期55卷 1042-1051页

作者： GAO Yan 1,CHEN ZhiHua 2,CHEN MinGang 3.& SHEN Yang 3.1 Software engineering institute,East china Normal University,Shanghai 200062,{3. 2 Department of Computer Science and engineering,East china University of Science and Technology,Shanghai 20023.,{3. 3.Department of Computer Science and engineering,Shanghai Jiao Tong University,Shanghai 200240,{3. 1. Software engineering institute East China Normal University Shanghai 200062 China2. Department of Computer Science and Engineering East China University of Science and Technology Shanghai 200237 China3. Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

Motion graphs have been widely used as an effective technique in the synthesis of human *** synthesize well-formed motions,motion graphs require smooth transitions and good ***,the time and costs grow quadratically as the graph size *** this paper,we present a method to set up a hierarchical structure,called a structure *** coarse level of this graph models different motion categories and their transitions,and the fine level mainly captures different motion *** interpolation space method is used to improve the graph connectivity at the fine *** structure guides the establishment of a faster and more realistic graphical *** the building process,this structure also helps with searching the motion graph,by performing a traverse search and placing the findings into a direct look-up table or local search ***,when there is no direct link between the different motions,a navigation map is introduced to conduct an appropriate search path via a series of transition motion *** experimental results indicate that our approach could lower the computation time in construction and searching,while simultaneously providing a richer variety of motion styles.

关键词： motion graph structure table registration curve motion interpolation

One-pot synthesis of crystalline SnO_2 nanoparticles and their low-temperature ethanol sensing characteristics

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1601-1605页

作者： CHEN YuJin1,2,3.ZHU ChunLing4,WANG LiJiao3.& WANG TaiHong2 1 School of Materials Science and engineering,Beijing institute of Technology,Beijing 100081,china 2 Micro-Nano Technologies {3. Center,Hunan University,Changsha 410082,china 3.College of Science,Harbin engineering University,Harbin 150001,china 4 College of Material Science and Chemical engineering,Harbin engineering University,Harbin 150001,china School of Materials Science and engineering Beijing Institute of Technology Beijing 100081 China Micro-Nano Technologies research Center Hunan University Changsha 410082 China College of Science Harbin Engineering University Harbin 150001 China College of Material Science and Chemical engineering Harbin Engineering University Harbin 150001 China

Crystalline SnO2 nanoparticles(NPs) with a diameter less than 6 nm are synthesized using potassium stannate trihydrate as the precursor in a basic *** synthesized NPs can detect ethanol at a ppm level even at 100℃.Furthermore,the NPs have good selectivity to *** excellent ethanol sensing performances are attributed to the small size effect according to the space-charge model.

关键词： SnO2 nanoparticles sensing characteristics

Friction behavior of coupling motion for natural articular cartilage by reciprocating rotation

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Chinese Science Bulletin 2009年第4期54卷 576-583页

作者： QIAN ShanHua1,2,3.& GE ShiRong1,3.1 College of Mechano-electronic engineering, china University of Mining & Technology, Xuzhou 221116, china 2 {3. of Tribology and Reliability engineering, china University of Mining & Technology, Xuzhou 221116, china 3.Biotribology Center, State Key Laboratory of Tribology, Xuzhou 221116, china College of Mechano-electronic engineering China University of Mining & Technology Xuzhou 221116 China institute of Tribology and Reliability engineering China University of Mining & Technology Xuzhou 221116 China Biotribology Center State Key Laboratory of Tribology Xuzhou 221116 China

Based on the irregular surface of natural cartilage configurations, the tribological characteristics of coupling motion between natural cartilage pairs were investigated by the variation of rotated offset and velocity. Contact displacement, contact load, friction force and coefficient of friction from natural cartilage pairs were measured by a UMT-2 testing machine. In order to obtain the steady part and wavy part, the contact load and contact displacement were decompounded by the five-point sliding average method. these results showed that the contact load was composed of steady load and wavy load. And the contact displacement was composed of cartilage deformation and surface outline. the steady load was similar to exterior load while natural cartilage deformation increased nonlinearly with the sliding time. Wavy load had the correlative coefficient 0.23. with surface outline due to the irregular surface of friction configurations. the coefficient of friction from cartilage friction configurations was less influenced by smaller magnitude in rotated parameters. A few strange summits were obtained in the area of coef-ficient of friction, and significantly related with local minimal values corresponding to the contact loads. the rotated offsets had clear impact on contact load and a slight impact on contact displacement. Larger offset produced higher wavy magnitude of the contact load. the rotated velocities played an evident role in cartilage deformation, but had a less influence on contact load. Lower velocity brought larger cartilage deformation.

关键词：软骨构造关节软骨摩擦系数软骨变形接触装

Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

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Chinese Science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. the research Center of Mineral Resources Exploration , Chinese Academy of Sciences , Beijing 100101, china 2. {3. of Geology , Chinese Academy of Sciences , Beijing 100029, china 3. {3. of High Energy Physics , Chinese Academy of Sciences , Beijing 100817 , china 4. Beijing University of Science and engineering , Beijing 100083. china Corresponding author the research Center of Mineral Resources Exploration Chinese Academy of Sciences Beijing China institute of Geology Chinese Academy of Sciences Beijing China institute of High Energy Physics Chinese Academy of Sciences Beijing China Beijing University of Science and engineering Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. the chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

Preliminary analysis of the hanging wall effect and velocity pulse of the 5.12 Wenchuan earthquake

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Earthquake engineering and engineering Vibration 2009年第2期8卷 165-177页

作者： Liu Qifang and Li Xiaojun institute of engineering Mechanics, china Ear{3.quake Administration, Harbin 150080, china Associate Professor Professor institute of engineering Mechanics China Earthquake Administration Harbin 150080 China institute of engineering Mechanics China Earthquake Administration 9 Xuefu Road Harbin 150080 China

A preliminary study of the PGA attenuation, hanging wall effect and velocity pulse characteristics from the 2008 Wenchuan earthquake ofMS -8.0 is described in this paper. the study was carried out through analyses in the time and frequency domains of main earthquake records. In the PGA attenuation study, records from 316 stations less than 1000 km from the surface rupture of the fault were used as a database and attenuation relationships were developed and compared with some existing relationships that are widely used in china's Mainland, Chinese Taiwan and the US. At the same time, records from 28 stations less than 100 km from the fault were used to study the hanging wall effect and velocity pulse characteristics of this earthquake based on the distribution of PGA, PGV, spectral acceleration, and the velocity pulse peak, and the results are compared with the 1999 Chi-Chi earthquake. In addition, the large PGAs of the UD components observed in this event are also discussed in this paper. From the results of the preliminary study, some conclusions are developed and suggestions for further research are proposed.

关键词： Wenchuan earthquake hanging wall effect velocity pulse attenuation