检索结果-南通市图书馆

Journal of Environmental sciences 2000年第4期12卷 463-468页

作者： DONG Yun\|she 1,2.3., Dieter Scharffe 2. Manfred Domroes 3. QI Yu chun 1, ZHANG Shen 1 (1. {2. of Geographic sciences and Natural Resources Research,{2.,{3., China E\|mail: dongys@*** 2. M 中科院地理科学与资源所北京 1 0 0 1 0 Max- Planck-institute of Chemistry 德国 Mainz 550 2 0 Mainz University 德国 Mainz 550 99

An enclosed chamber technique was used to measure N 2. emissions from intensively agricultural soils of the North China Plain during the periods of 1995—1996 and 1997—1998, to reflect distinct components of winter wheat and summer maize growing seasons. The results showed that the continuous application of fertilizer in agricultural soils increased N\-2. emissions by a factor of 2..1—2..1, the calculated annual chemical N fertilizer\|transformed N\-2.\|N emissions was 0.67%. Our results indicated that the application of organic manure also had a significant influence on soil N 2. emissions, which combined with the use of chemical N increased about 2.% in a year. It was calculated that there were about 0.11% N of organic manure transformed as N 2. N. Annual mean N 2. emission from our study area of fertilized soils was estimated to be 57.1 μgN 2./(m 2.h). A weak correlation was also found between N 2. emissions and soil available nitrogen content NH + 4.

关键词： N_2. emissions the North China Plain agricultural soils chemical nitrogen organic manure

Two special topics on the avian influenza virus and on epigenetics,have drawn much attention

在线全文

学校读者我要写书评

暂无评论

Science China(Life sciences) 2010年第12期53卷 1483-1484页

作者： HU YongLin institute of Biophysics,chinese {2. of {3.,beijing 100101,China institute of Biophysics Chinese Academy of Sciences Beijing China

Several excellent well-organized reviews and research papers on two special topics, "The challenges of avian influenza virus: mechanism, epidemiology, and control" and "Molecular

关键词： APOBEC gene Two special topics on the avian influenza virus and on epigenetics,have drawn much attention

Spatial heterogeneity of the driving forces of cropland change in China

在线全文

学校读者我要写书评

暂无评论

Science China Earth sciences 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2. WANG Jinfeng1, LIU Mingliang4,1 & MENG Bin1,2.3.1. institute of Geographic {2. and Natural Resources Research,{2.,{3., China 2. Graduate School of the{2., beijing 10003., China 3. College of Arts and {2. of beijing Union University, beijing 100083. China 4. School of Forestry and Wildlife {2., Auburn University, Auburn, Alabama, AL3.849, USA institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Graduate School of the chinese academy of sciences Beijing China School of Forestry and Wildlife sciences Auburn University Auburn Alabama USA College of Arts and sciences of beijing Union University Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2.00 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in China. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of China, natural condition changes and geographical background were the main constraints and drivers, while in Eastern China, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in China recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, China.

Discovery of microchromosomes in wheat and their special behavior in meiosis

在线全文

学校读者我要写书评

暂无评论

chinese Science Bulletin 1997年第24期42卷 2084-2087页

作者： XU Qi, YU Ling, TIAN Zengrong, ZHU Jianfeng, LI Bin and LI Zhensheng Laboratory of Plant Genetic Engineering and Breeding of Shaanxi Province, Northwestern institute of Botany, chinese academy of sciences, Yangling, Shaanxi 712.00, China 2. State Key Laboratory of Plant Cell and Chromosome Engineering, institute of {3., chinese academy of sciences, beijing 100101, China Laboratory of Plant Genetic Engineering and Breeding of Shaanxi Province Northwestern Institute of Botany Chinese Academy of Sciences Yangling Shaanxi China State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics Chinese Academy of Sciences Beijing China

THERE are 42.chromosomes in common wheat (Triticum aestivum L). The extra microchro-mosomes were discovered in alloplasmic lines of common wheat with cytoplasms of Ae. muti-ca, Secale cereale, Elytrigia elongatum and Agropyron glaucum. The microchromo-somes were discovered in amphiploid of Triticum aestivum-Secale cereale (DDRR) too.

关键词： wheat microchromosomes behavior in meiosis.

The effects of K^+ growth conditions on the accumulation of cesium by the bacterium Thermus sp. TibetanG6

在线全文

学校读者我要写书评

暂无评论

Science China(Life sciences) 2006年第2期49卷 123-129页

作者： WANG Hailei1,2.3. KONG Fanjing1,2.3.& ZHENG Mianping1,2.3.1. R&D Center for Saline Lake and Epithermal Deposits, chinese academy of Geological {2., {3. 10003., China 2. Key Open Laboratory of Saline Lake Resources and Environment, chinese academy of Geological {2., {3. 10003., China 3. institute of Mineral Resources, chinese academy of Geological {2., {3. 10003., China R&D Center for Saline Lake and Epithermal Deposits Chinese Academy of Geological Sciences Beijing China Key Open Laboratory of Saline Lake Resources and Environment Chinese Academy of Geological Sciences Beijing China institute of Mineral Resources Chinese Academy of Geological Sciences Beijing China

The accumulation of cesium by the bacterium Thermus sp. TibetanG6 was examined under different K+ growth conditions. The effects of external pH and Na+ on the accumulation of ce-sium were also studied, and the mechanism involved was discussed. K+ regimes played an important role in the accumulation of cesium by the strain TibetanG6. The quantity of cesium accumulated (2. h) was much higher in K+-deficient regime than that in K+-sufficient regime. The pH and Na+ had different effects on the accumulation of cesium in the two K+ regimes. IR spectra analyses indicated that the biosorption is a process of homeostasis with cesium initially accumulated on the cell wall.

关键词： Thermus sp. TibetanG6, cesium, bioaccumulation, K+-growth condition, pH, sodium, IR spectroscopy.

UV-visible Absorption Studies of Tetrachloro-p-benzoquinone and Tertiary Amines Charge Transfer Complexes in Trichloromcthane

在线全文

学校读者我要写书评

暂无评论

chinese Chemical Letters 1999年第12期10卷 0-0,0-0页

作者： Fang GAO Yong Yuan YANG(institute of Photographic Chemistry, The chinese academy of sciences,{2.) institute of Photographic Chemistry Chinese Academy of Sciences Beijing 100101 China

The spectophotometry of charge transfer (CT) complexes of tetrachloro-p-benzoquinone(TCB) with tertiary amine [triethylamine (TEA), triphylamine (TPA), N,N-dimethylphenylamine(DMPA), N-ethylcarbazole (ECZ)] have been studied in dichloromethane in UV-visible *** CT complexes parameter, molar ratio of reactAnts in complex, molar extinction coefficient equilibrium constant KCT, free energy G and dissociation energy of the CT complex excited stateE, have also been estimated and discussed.

关键词： Spectophotometry charge transfer tertiary amine tetrach loro-p-benzoqu inone.

Monitoring Dynamic Change of Land Cover Based on SVM and Satellite Images in Hanoi,Vietnam

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural sciences 2010年第4期15卷 355-362页

作者： ZHAO Jinling1,2. LIU Chuang1, 3.1. institute of Geographic {2. and Natural Resources Research,{2.,{3., China 2. Graduate University of{2., beijing 100049, China 3. College of Resources Science and Technology, beijing Normal University, beijing 100875, China institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China College of Resources Science and Technology Beijing Normal University Beijing China

An integral method,combining support vector ma-chine (SVM) with remote-sensing analysis techniques,was ex-plored to monitor Hanoi’s dynamic change of land cover. The landsat thematic mapper (TM) image in 1993.the enhanced the-matic mapper plus (ETM+) image in 2.00,and the image with the charge-coupled device camera (CCD) on the China-Brazil earth resources satellite (CBERS) in 2.08 were used. Six land-cover types,including built-up areas,woodland,cropland,sand,water body and unused land,were identified. The detected results showed visually the rapid urban expansion as well as land-cover change of Hanoi from 1993.to 2.08. There were 12.63..54 hm2.cropland de-creased between 1993.and 2.00,and 8 2.7.6 hm2.cropland de-creased between 2.00 and 2.08. Compared with cropland,wood-land firstly decreased and then increased,and the other types did not change significantly. The results indicate that CBERS dataset has the application potential in world resources researches.

关键词： land cover the China-Brazil earth resources satellite (CBERS) support vector machine (SVM) change detection

Inertial theory of the mean Hadley circulation under the condition of nonstatic equilibrium

在线全文

学校读者我要写书评

暂无评论

Science China Earth sciences 2006年第5期49卷 546-553页

作者： CHAO Jiping1 & LIU Fei2.3.1. National Marine Environmental Forecasting Center, beijing 100081, China 2. Key Laboratory Regional Climate-Environment for Temperate East Asia, {2. of Atmospheric Physics,{2., beijing 10002., China 3. Graduate University of{2., beijing 100049, China National Marine Environmental Forecasting Center Beijing China Key Laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

Tropical atmosphere is divided into two layers, the layer near the ground is the planet boundary layer, where the motion is linear, if the radiation equilibrium temperature is given at the top of the boundary layer, the vertical motion there can be obtained. It is the non-viscous ideal atmos- pheric layer above the boundary one, where the motion is nonlinear. After getting the conservation laws of angular momentum, potential temperature and potential vortex, the inertial theory of the Hadley circulation driven by the vertical motion of the boundary layer is established, followed by sev- eral examples of its application.

关键词： Hadley circulation, inertial theory, conservation laws of angular momentum, potential temperature and potential vortex.

Principles and methods of quantitative analysis on b-axis disorder in 2.: 1 dioctahedral phyllosilicate

在线全文

学校读者我要写书评

暂无评论

chinese Science Bulletin 1997年第22期42卷 1908-1912页

作者： WANG Ling and ZHANG Zhenyu1. Changsha institute of Geotectonics, chinese academy of sciences, Changsha 41001{2. China 2. institute of Geology, chinese academy of sciences, beijing 10002., China Changsha institute of Geotectonics Chinese Academy of Sciences Changsha China institute of Geology Chinese Academy of Sciences Beijing China

IN XRD patterns of clay minerals, a phenomenon that strong peaks often have (00l) and(hkl) (k=3.) indices and show symmetric figures can be seen commonly, while a minorityof reflection peaks (hkl) (k≠3.) are comparat... 详细信息

关键词： b-axis disorder pyrophvllile 2 phyllosilicate clay minerals dioctahedral minerals orientating structure of hy-droxyls crystal structure analysis DTA-TG.

Biomass estimation and uncertainty analysis based on CBERS-02.CCD camera data and field measurement

在线全文

学校读者我要写书评

暂无评论

Science China(Technological sciences) 2005年第S2期48卷 116-128页

作者： CHEN Liangfu1,2. GAO Yanhua1,3. CHENG Yu1,3. WEI Zheng1,3. XIAO Qing1,4, LIU Qinhuo1, YU Tao1, LIU Qijing5, GU Xingfa1 & TIAN Guoliang1 1. State Key Laboratory of Remote Sensing Science, institute of Remote Sensing Applications, chinese academy of sciences,{2., China 2. Geography and Environment College, Jiangxi Normal University, Nanchang 3.002., China 3. Graduate University of chinese academy of sciences, beijing 10003., China 4. beijing Research institute of Uranium Geology, beijing 100875, China 5. institute of Geographic sciences and Natural Resources Research, chinese academy of sciences,{2., China State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Geography and Environment College Jiangxi Normal University Nanchang 330027 China Graduate University Chinese Academy of Sciences Beijing 100039 China beijing Research institute of Uranium Geology Beijing 100875 China institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

The study site is located in Qianyanzhou experimental station and the surrounding area. Based on CBERS-02.satellite data and field measurement, we not only discussed the relationship between NDVI and biomass of two species of coniferous plantations, namely, Pinus massoniana Lamb and Pinus elliottii Engelm, but also introduced the biomass models based on NDVI. The comparison between measured biomass in Qianyanzhou and biomass derived from CBERS-02.CCD data showed that it is feasible to estimate biomass based on NDVI. But its limitations cannot be ignored. This kind of model depends on the dominant vegetation species. There are some effect factors in estimating biomass based on NDVI. This paper analyzes these factors based on fine-resolution CBERS-02.CCD data and some conclusions are drawn: In Qianyanzhou, the area with good vegetation coverage, the nonlinearity of NDVI has little influence on scaling-up of NDVI. As a result of surface heterogeneity, scaling-up can cause NDVI within each pixel to change. Because scaling-up can cause pixel attribute to change, the applicability of biomass model is one of the sources of error in estimating biomass.

关键词： NDVI biomass scaling effect scaling-up.