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Some characteristics of the atmosphere during an adiabatic process

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Progress in Natural Science:Materials International 2006年第6期16卷 644-648页

作者： GAO Li, LI Jianping and REN Hongli (LASG, institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 10002., china Graduate School of Chinese Academy of Sciences, beijing 10004., china National Climate Center, Laboratory of Climate Studies, china Meteorological administration, beijing 100081, china) [a]LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China [b]Graduate School of Chinese Academy of Sciences Beijing China [c]National Climate Center Laboratory of Climatic Studies China Meterological Administration Beijing China

Some important characteristics of the atmosphere during an adiabatic process are investigated, which include the invariability of atmospheric entropy range and local surface potential temperature, the conservation of the atmospheric mass intervened between any isentropic surface and the ground, and the isentropic surface intersecting with the ground. The analysis shows that the atmospheric reference state (ARS) for investigation on available potential energy (APE) should be defined objectively as the state which could be approached from the existing atmosphere by adiabatic adjustment, and be related to initial atmospheric state before adjustment. For the initial atmosphere state at any time, its corresponding ARS is different from the one at another time. Based on the above-mentioned conclusions, the reference state proposed by Lorenz cannot be obtained physically, so a new conception, the conditional minimum total potential energy, is put forward in order to objectively investigate atmospheric APE.

关键词： available potential energy adiabatic isentropic surface atmospheric reference state conditional minimum total potential energy.

Quantitative analysis of torrential rainfall associated with typhoon landfall:A case study of typhoon Haitang(2005)

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Progress in Natural Science:Materials International 2009年第1期19卷 55-63页

作者： Caijun Yue a,b,a Shanghai Typhoon institute,the china Meterological administration Shanghai 200030,china b Laboratory of Typhoon Forecast Technique/china Meterological administration,Shangai 200030,china [a]Shanghai Typhoon institute the china Meterological Administration Shanghai 200030 China [b]Laboratory of Typhoon Forecast Technique/China Meterological Administration Shangai 200030 China

A quantitative analysis of torrential rainfall associated with typhoon Haitang(2005) is carried out using a modified moist ageostrophic Q vector and data from Weather Research and Forecasting(WRF) model *** major factors determining the ascending motion associated with torrential rainfall have been studied:large-scale and convective condensational heating,topographic lifting and *** results show that the convective condensational heating plays a major role in the torrential rainfall process,and the large-scale condensational heating is secondary before the landfall of typhoon Haitang,and vice versa after the *** topographic lifting affects the formation of rainfall,whereas the topographic friction has important impacts on torrential rainfall after the *** rainfall amounts forced by the topographic friction and lifting have similar horizontal distributions,but the magnitudes of the former are 2-3 times larger than those of the *** rainfall amounts forced by topography(lifting and friction) and modified moist ageostrophic Q vector have different horizontal distributions,and the magnitudes of the former are 2-5 times larger than those of the *** analysis shows that the typhoon rainfall may be motivated by modified moist ageostrophic Q vector and enhanced further by the topographic effects.

关键词： Torrential rainfall Typhoon landfall Modi?ed moist ageostrophic Q vector Topography Condensational heating Quantitative analysis

Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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Science china Earth Sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2,3, ZHANG Yili1, BAI Wanqi1, LIU Yanhua4. BAO Weikai5, LIU Linshan1, 2 & ZHENG Du1 1. institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101, china 2. Graduate School of the Chinese Academy of Sciences, beijing 100039, china 3. College of Resources and Environment, Southwest Agricultural University, Chongqing 4.0716, china 4. The Ministry of Science and Technology, P. C. china, beijing 100862, china 5. Chengdu institute of Biology, Chinese Academy of Sciences, Chengdu 61004., china 1. institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate School of the Chinese Academy of Sciences 100039 Beijing China 3. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China 4. The Ministry of Science and Technology P. C. China 100862 Beijing China 5. Chengdu institute of Biology Chinese Academy of Sciences 610041 Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2000 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2000, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.4.%. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2000, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

Age of Yingfeng rapakivi granite pluton on the north flank of Qaidam and its geological significance

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Science china Earth Sciences 2004年第4期47卷 357-365页

作者： XIAO Qinghui1,2, LU Xinxiang1,3, WANG Fei4. SUN Yangui5, WEI Xiangdong3 & XING Zuoyun6 1. Division of Granite Geology, china Geological Survey, Yichang 4.3003, china 2. Information Center of Ministry of Land and Resources, beijing 100812. china 3. Geological Survey of Henan Province and institute of Geological Research of Henan Province, Zhengzhou 4.0053, china 4. Geological institute, china Seismological Bureau, beijing 10002., china 5. Geological Survey institute of Qinghai Province, Xining 810032, china 6. china University of Geosciences, Wuhan 4.0074. china Division of Granite Geology China Geological Survey Yichang 443003 China Information Center of Ministry of Land and Resources Beijing 100812 China Geological Survey of Henan Province and institute of Geological Research of Henan Province Zhengzhou 450053 China Geological institute China Seismological Bureau Beijing 100029 China Geological Survey institute of Qinghai Province Xining 810032 China china University of Geosciences Wuhan 430074 China

The Yingfeng rapakivi granite on the north flank of Qaidam is a newly discovered Proterozoic rapakivi pluton in china, which was found after the discovery of Shachang rapakivi in Miyun County, beijing and Kuandian rapakivi in Jilin Province. Yingfeng rapakivi pluton is ex-posed on the north side of the suture belt between Qinling-Kunlun orogenic belt and North china plate. U-Pb zircon isotopic dating and Ar-Ar isotopic dating of both hornblende and K-feldspar from the Yingfeng rapakivi granite have been conducted. The results show that the age of (1776±33)Ma at the upper intercept in Concorde diagram represents the age of formation of the plu-ton, whereas the age of (526 281) Ma at the lower intercept and Ar-Ar mineral dating of horn-blende and K-feldspar correspond to the age of a later event affecting the pluton, suggesting that Yingfeng pluton has ever been affected by strong regional Caledonian-Hercynian tectonic movement after its formation. The discovery of middle Proterozoic Yingfeng rapakivi granite pro-vides a petrologic evidence for the timing of cratonization of both the continental crust basement in western china and the basement of the North china plate and for a rifting event taking place in the mid-Proterozoic, suggesting that an amalgamation of ancient china continents had ever happened during the L liang Movement?between the early Proterozoic and the mid-Proterozoic.

关键词： rapakivi, U-Pb dating, Ar-Ar dating, Kunlun-Qinling orogenic belt.

ANALYSIS OF CAPITAL FLOW WITH GIS——Two Approaches for Regional Investment in china

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Chinese Geographical Science 2003年第1期13卷 2-8页

作者： YAO Yong-ling ( Public administration School, Renmin University of china, beijing 100872, P. R. china) Public administration School Renmin University of China Beijing 100872 P. R. China

GIS technology has been mostly concerned with handling physical data andmodeling physical environment. However, the retirements of GIS for handling socio-economicinformation in many cases are different from those concerning phenomena in the physical *** of capital flow among regions requires the transitions both from economic values tophysical landscape and from physical surface to economic explanation. Rapid growth of Chineseeconomy comes mainly from investment. There are two main ways for obtaining high growth ofinvestment. One is government expenditure which usually invests in regional facility and amenityblock, which is regarded as stimulus for attracting investment. The other is the creation ofinvesting center and corresponding capital source areas, both of which need the central city withthe highest growth rate of investment among regions. This paper presents the cluster areas of bothgovernment revenue and total investment, the potential situation of capital flow between centralcity Shanghai and its neighbor provinces by using Classification' and Interpolation' functions ofArcView GIS.

关键词： capital flow geographic information system (GIS) regional investment cluster analysis

EFFECT OF MICROSTRUCTURE OF ALUMINIDE COATING ON HIGH-CYCLE FATIGUE PERFORMANCE OF COATING-SUPERALLOY SYSTEM

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Acta Metallurgica Sinica(English Letters) 1992年第2期5卷 121-127页

作者： FA N Ruilin institute of Aeronautical Materials,beijing,china Inst of Aeronautical Materials Beijing China

The high-cycle fatigue performance of different microstructures of aluminide coating- superalloy system has been studied at 900℃.The single phase coating of coarse equiaxial grain NiAI(β)has unfavorable eJfect onJatigue life of the *** fatigue life may shorten if the coating of NiAl(β)was an enrichment of coarse refractory metal grains. While an improvement can be made by dispersing numerous secondary phase particles such as *** γ′,quasi-σ-phase and others.

关键词： aluminide coating coating microstructure high temperature high cycle fatigue

Estimating surface evapotranspiration using combined MODIS and CBERS-02 data

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Science china(Technological Sciences) 2005年第S2期48卷 145-160页

作者： XIN Xiaozhou1,2, LIU Qinhuo1, TANG Yong1,3, TIAN Guoliang1, GU Xingfa1, LI Xiaowen1,2, ZHENG Hongsheng4.& CHEN Jiayi4.1. State Key Laboratory of Remote Sensing Science, institute of Remote Sensing Applications, Chinese Academy of Sciences, beijing 100101, china 2. Research Center for Remote Sensing and GIS, Department of Geography, beijing Normal University, beijing 100875, china 3. Graduate University of Chinese Academy of Sciences, beijing 100039, china 4. Department of Atmospheric Physics, Peking University, beijing 100871, china 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China2. Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University 100875 Beijing China3. Graduate University of Chinese Academy of Sciences 100039 Beijing China4. Department of Atmospheric Physics Peking University 100871 Beijing China

Spatial scale error is one of the most serious problems in the estimates of land surface heat fluxes of sensible and latent from satellite-borne data such as MODIS 1km resolution reflectance and emissive data. One of the feasible and economic ways to decrease the spatial scale error is to use high resolution land use class data together with the MODIS data. CBERS-02 data were used to produce land use class of Baiyangdian area, Hebei Province, china in the autumn of 2004. The area ratio of each class in MODIS pixel was calculated, and used to derive the heat fluxes of the mixed pixel. The results showed that the estimated heat fluxes of soil, sensible and latent have been changed remarkably after using the high resolution land class data. It could be concluded from the comparison between simulated and ground-measured fluxes as well as the theoretical analysis that high resolution land class data are useful to diminishing the scale error of heat fluxes estimated from low resolution satellite data.

关键词： surface evapotranspiration spatial scale error MODIS CBERS land class.

Locating seismic scatterers at the base of the mantle beneath eastern Tibet with PKIKP precursors

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Chinese Science Bulletin 2010年第24期55卷 723-729页

作者： SHEN XuZhang 1,2,3 & ZHOU HuiLan 1 1 Laboratory of Computational Geodynamics,Graduate University of the Chinese Academy of Sciences,beijing 10004.,china 2 Lanzhou institute of Seismology,china {4. administration,Lanzhou 730000,china 3 Lanzhou Base of institute of {4. Prediction,china {4. administration,Lanzhou 730000,china Laboratory of Computational Geodynamics Graduate University of the Chinese Academy of Sciences Beijing China Lanzhou institute of Seismology China Earthquake Administration Lanzhou China Lanzhou Base of institute of earthquake Prediction China Earthquake Administration Lanzhou China

Clear PKIKP precursors were observed from the Lanzhou CTBTO seismic *** measured their incident angles,arriving azimuths and differential travel times with respect to the PKIKP arrivals using array analysis *** measurements allowed us to locate the scatterers that generated the observed *** found that the scatterers are located in the lowermost mantle beneath eastern Tibet,which is featured by a high-velocity anomaly based on previous tomographic *** high velocity anomaly was interpreted as the slab remnants of the ancient Tethys *** thus speculate that the observed scatterers are either related or induced by the subducted slab.

关键词：地震前兆西藏东部下地幔散射定位地震台阵入射角度旅行时间

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The quantification of remote sensing

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Science china(Technological Sciences) 2005年第S2期48卷 1-11页

作者： GU Xingfa1,2,3,TIAN Guoliang1,2, LI Xiaowen1,2 & GUO Jianning4.1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University, beijing 100101, china 2. The Center for National Spaceborne Demonstration, beijing 100101, china 3. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84.14.Avignon, France 4. china Center for Resource Satellite Data and Application, beijing 100830, china Chinese Acad Sci Inst Remote Sensing Applicat State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China beijing Normal Univ State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Ctr Natl Spaceborne Demonstrat Beijing 100101 Peoples R China Inst Natl Rech Agron F-84914 Avignon France china Ctr Resource Satellite Data & Applicat Beijing 100830 Peoples R China

The paper firstly defined the remote sensing information quantification, analyzed the necessity of developing remote sensing quantification, figured out the application guidelines requirement, and pointed out the importance of quantification research. Then taking the remote sensing application research of CBERS-02 data quantification as the example, the paper described the whole quantification system of “remotely sensed digital signal-radiation information-field parameter inversion”. Finally the paper gave the prospect for the development trend of the quantitative remote sensing.

关键词： remote sensing information quantification CBERS-02 radiometric calibration surface parame- ter reversion.