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Quantitative analysis of soil pores under natural vegetation successions on the Loess Plateau

Science china Earth sciences 2010年第4期53卷 617-625页

作者： ZHAO ShiWei1,ZHAO YongGang1,2 & WU JinShui3.1 State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Institute of Soil and Water Conservation,Northwest Agriculture & Forestry University,Yangling 712100,china 2 Graduate University of chinese academy of sciences,Beijing 100049,china 3.Institute of Subtropical Agriculture,chinese academy of sciences,changsha 410125,china 1. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Northwest Agriculture & Forestry University Yangling 712100 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 China

Soil pore is a key attribute of the soil structure that affects soil reservoir under natural vegetation recovery on the Loess *** study is to quantitatively analyze soil pore parameters,measured with Computed Tomography(CT) at 15-57 mm depths under five different vegetation succession stages using a concept of substituting "space" for "time" in the Ziwuling Forest Region of the Loess *** results showed that the soil pore parameters,such as pore number,porosity,circularity,and fractal dimension,increased significantly under the natural vegetation successions and varied with the pattern climax community stage>pioneering arbor community stage>scrub community stage>herbaceous community stage>abandoned farmland stage,indicating that natural vegetation recovery could remarkably improve soil pore *** the vegetation succession,this positive effect will be strengthened gradually,which means that the soil pore parameters may appear to be best at the climax community *** organic matter content increased linearly with the soil pore parameters(P<0.001).Increased organic matter accumulation was one of the major reasons for the changes in soil pore characteristics in natural vegetation succession.

关键词： Computed Tomography Loess Plateau natural vegetation succession soil pore soil organic matter

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

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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{3. {{3. 2. Institute of Geology, chinese academy of sciences, Beijing 100029, {{3. 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.

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High-temperature phases of pyrophyllite and their evolutionary characteristics

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chinese Science Bulletin 1997年第2期42卷 140-144页

作者： WANG Ling and ZHANG Zhenyu1. changsha Institute of Geotectonics, chinese academy of sciences, changsha 41001{3. {{3. 2. Institute of Geology, chinese academy of sciences, Beijing 100029, {{3. changsha Institute of Ceotectonics Chinese Academy of Sciences Changsha China Institute of Geology Chinese Academy of Sciences Beijing China

WITH the increase of heating temperature, phase of pyrophyllite will undergo a series of transformations. Former scholars have done some work in this respect; the temperature spans,however, were normally not more than 1150℃ and no relatively comprehensive results have been reported. Thus, the features of the phases from indoor temperature to melting point (1710℃±) for pyrophyllite and the entire evolutionary process of the phases are uncertain.

关键词： pyrophyllite high-temperature phase phase tranformation pyrophyllite anhydrite mullite cristobalite.

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^(13.)Cs Redistribution in Thin Stony Soil of a Carbonate Rock Slope in Southwest china

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Pedosphere 2011年第1期21卷 37-45页

作者： LI Hao ZHANG Xin-Bao WANG Kc-Lin WEN An-Bang Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 (China) Graduate University Chinese Academy of Sciences Beijing 100049 (China) State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 (China) Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 (China)

The fallout radionuclide cesium-13.(13. Cs) has been widely employed as a tracer for assessment of soil loss from thick uniform soils;however,few studies have been conducted on thin stony soils on slopes underlain by carbonate rocks which are widely distributed in karst *** derived from 13. Cs measurement of soil samples collected along a carbonate rock slope with thin stony soil where neither soil erosion nor deposition occurred was used to investigate the characteristics of 13. Cs redistribution in a karst area of Southwest *** results indicated that the 13. Cs inventories of the surface soil on the slope studied were much lower than that of the local 13. Cs reference inventory and the 13. Cs activities were much higher than those on slopes with thick uniform *** spatial distribution of 13. Cs inventories was characterized by considerable *** high 13. Cs depletion in the stony soil of the slope studied was mainly because a considerable proportion of the fallout input of 13. Cs could be lost with runoff and the dissolution of carbonate particles in the soil promoted the loss of 13. *** demonstrated that the rates of soil loss could not be estimated from the degree of depletion of the 13. Cs inventory relative to the local reference inventory for the thin stony soil of the rocky slope underlain by carbonate rocks in the study area in the way that has been widely used in areas with thick uniform soils.

关键词： carbonate dissolution, ^13.Cs fallout, ^13.Cs inventory karst area runoff

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Mean Convergence of Lagrange Type Interpolation on an Arbitrary System of Nodes

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Acta Mathematicae Applicatae Sinica 2002年第2期18卷 277-288页

作者： Ying-guang ShiDepartment of Mathematics, Hunan Normal University, changsha 410081, china & academy of Mathematics and System {{3., chinese academy of sciences, Beijing 100080, china Department of Mathematics Hunan Normal University Changsha 410081 China academy of Mathematics and System sciences Chinese Academy of Sciences Beijing 100080 China

Sufficient conditions of convergence and rate of convergence for Lagrange type interpolation in the weighted Lp norm on an arbitrary system of nodes are given.

关键词： Lagrange type interpolation convergence rate of convergence

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The Cation Exchange Capacity of Fibrous Feedstuff and Its Nutritive Characteristics

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Agricultural sciences in china 2003年第1期2卷 98-106页

作者： XING Ting-xianchangsha Institute of Agricultural Modernization , chinese academy of sciences , changsha 410125 , P. R. {{3. changsha Institute of Agricultural Modernization Chinese Academy of SciencesChangsha 410125 P. R. China

Current researches on the nutritive characteristics of fibrous feedstuff through determining the feedstuff cation exchange capacity (CEC) to evaluate its nutritive value at home and abroad were comprehensively discribed. and the methods of determining CEC value and the correlation between CEC value and chemical compositions, pH value, and the effect of CEC value on the digestion kinetics in ruminants were also emphatically introduced. The results of research showed that the CEC values of different feedstuff are different, closely correlated with nitrogen and acid detergent fibre (ADF) and lignin (LIG) content of the feedstuff. At the same time, there are markedly effect of CEC value in diet on the nutrients flow of digesta in the digestive tract of ruminants, the degradation rate and digestibility of nutrients in the rumen.

关键词： Cation exchange capacity Fibrous feedstuff Buffering capacity Digestion kinetics in rumen

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CONVERGENCE OF (0,1,2,3. INTERPOLATION ON AN ARBITRARY SYSTEM OF NODES

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Journal of Computational Mathematics 2001年第2期19卷 151-156页

作者： Ying-guang Shi (Institute of Computation, Hunan Normal University, changsha 410081, china) (Institute of Computational Mathematics and Scientific/Engineering Computing, academy of Mathematics and Systems {{3., chinese academy of sciences, Beijing 100 湖南师范大学湖南长沙 410081

Provides information on a study which simplified and improved convergence of (0,1,2,3. interpolation on an arbitrary system of nodes. Definitions and notations; Results; Conjectures.

关键词： Hermite interpolation Hermite-Fejer interpolation convergence

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Identification and removal of block ambiguities in sea surface wind field with scatterometers

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Science china Earth sciences 2009年第2期52卷 242-249页

作者： CHEN KeHai1,2, XIE XueTong3.& FANG Yu4 1 South china Sea Institute of Oceanology, chinese academy of sciences, Guangzhou 5103.1, china 2 Graduate University of chinese academy of sciences, Beijing 100049, china 3.School of Electronic Science and Engineering, National University of Defense Technology, changsha 410073. china 4 The Institute of Remote Sensing and GIS, Peking University, Beijing 100871, china 1. South china Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China 2. Graduate University of chinese academy of sciences Beijing 100049 China 3. School of Electronic Science and Engineering National University of Defense Technology Changsha 410073 China 4. The Institute of Remote Sensing and GIS Peking University Beijing 100871 China

The solution of the current wind retrieval algorithm for scatterometers has several wind vector ambi-guities, due to the bi-harmonic relationship between normalized backscattering cross section and the relative wind direction and the existence of the measurement error. In order to remove the ambiguities for a unique wind field, a circular median filter approach (CMF) is usually adopted. But under the con-dition for clustering distribution of the false ambiguities in some local areas, the CMF fails and thus engenders block ambiguities, which degrade the precision of the retrieved wind field. For such a situation, a technique of identification and removal of the block ambiguities is presented to further optimize the retrieved wind field after CMF. It is demonstrated in experiment that this technique can identify and remove most of the block ambiguities.

关键词： scatterometer block ambiguity identification and removal

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Recent Advances in Development of Herbicide Resistant Transgenic Hybrid Rice in china

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Rice science 2009年第3期16卷 235-239页

作者： XIAO Guo-ying Institute of Subtropical AgricuIture Chinese Academy of Sciences Changsha 410125 China

In addition to weed control in direct seeding field of hybrid rice, herbicide resistance genes were used by chinese scientists to increase and identify the purity of hybrid seeds, and to realize the mechanization of hybrid seed production. The elite restorer lines, such as Minghui 63. R752, T461, R402, D68 and E3. were transformed directly with herbicide resistance genes, in which D68 and E3. are restorer lines of two-line system and the others are of three-line system. Because almost all of important restorer lines are indica varieties and are recalcitrant in transformation, many herbicide resistant near-isogenic restorer lines were developed by sexual hybridization of indica and japonica varieties and backcross with indica restorer lines later, such as Ce 64, Minghui 63. Teqing, Milyang 46, R402 and 93.1, in which 93.1 is a restorer line of two-line system. The elite photoperiod-sensitive/thermo-sensitive genic male sterile lines, such as Pei＇ai 64S, P88S, 4008S and 7001S, were transformed with herbicide resistance genes. A few herbicide resistant male sterile lines were developed through sexual hybridization and subsequently systemic selection, such as Bar1259S, Bar2172S, 05Z221A and 05Z227A. With the employment of herbicide resistant male sterile lines or herbicide resistant restorer lines, a few herbicide resistant hybrid rice combinations were developed, such as Xiang 125S/Bar 68-1 and Pei＇ai 64S/Bar 93.1. Based on herbicide resistance, the research was marching on to investigate the parental lines of hybrid rice with insect resistance, drought tolerance, etc.

关键词： hybrid rice herbicide resistance breeding transgene

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Oxygen Isotope Exchange Kinetics Between Coexisting Minerals and Water in the Aral Granite Pluton of the Altay Mountains, Northern Xinjiang

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Acta Geologica Sinica(English Edition) 1996年第4期70卷 366-379,452页

作者： Liu Wei,Research Center of Mineral Resources Exploration, chinese academy of sciences, chinese academy of sciences, BeijingHe Baichu, changsha Institute of Geotectonics, chinese academy of sciences, changsha, Hunanand Chen ZhenshengYichang Institute of Geology and Mineral Resources, chinese academy of Geologicalsciences, Yichang, Hubei

Coexisting quartz, feldspar and biotite vary widely in their δ18O values and display a remarkable 18O/16O disequilibrium relation; especially, a quartz-feldspar reversal (△ 18OQUartz_feldspar3.×10-14 mol. s-1) and high W/ R ratio (0.79-6.14). This means that an intense flow and convection may exist at the midcrustal level of erogenic magmatic arcs.

关键词： kinetics oxygen isotope exchange reaction granite Aral of Xinjiang

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