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Evaluation of Sustainable Land Management and Diagnosis of Obstacle at County Scale in Sichuan Basin:Taking Lezhi County as Example

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Wuhan University Journal of Natural sciences 2006年第4期11卷 1046-1051页

作者： CHEN Guangjian 1, 2, 3., LIU Qing 1 1. chengdu Institute of Biology, chinese academy of {3., chengdu 610041, Sichuan,china 2. Graduate University of chinese academy of {3., Beijing 100049, china 3. academy of Land Reconnaissance and Layout of Sichuan Province , chengdu 61003., Sichuan, china chengdu Institute of Biology Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate University of chinese academy of sciences 100049 Beijing China academy of Land Reconnaissance Layout of Sichuan Province 610031 Chengdu Sichuan China

This paper established sustainable land resources evaluating indicators fit for hilly area in Sichuan Basin, Southwest of china, and evaluated the case of sustainable land management of Lezhi County from 1990 to 2001. The result showed that the land resource sustainable utilization ability in Lezhi County is belong to Second level （better sustainable）. Secondly, this paper diagnosed some years obstacles of sustainable land management of Lezhi County from base period to goal period and compared the obstacles factors in the indicators system. There were 16 indexes orderly become major affect factor to land sustainable utilization of Lezhi county in indicator system, of which there are 8 obstacles indexes exist both in 1990 and 2001. The value of obstacles degree of five indicators exceeded 5 in 1990, but in 2001, only two indicators＇ values were more than 5.

关键词： land resources sustainable land management assessment indicators diagnosis of obstacle

Some basic inequalities in higher dimensional non-Euclid space

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Science china Mathematics 2007年第3期50卷 423-438页

作者： Ding-hua YANG College of Mathematics and Software sciences, Sichuan Normal University, chengdu 610066, china chengdu Institute of Computer Applications, chinese academy of sciences, chengdu 610041, china College of Mathematics and Software sciences Sichuan Normal UniversityChengdu 610066 China

In this paper, the concept of a finite mass-points system ΣN(H(A))(N > n) being in a sphere in an n-dimensional hyperbolic space H n and a finite mass-points system ΣN(S(A))(N > n) being in a hyperplane in an n-dimensional spherical space S n is introduced, then, the rank of the Cayley-Menger matrix-ΛN(H) (or a-ΛN(S)) of the finite mass-points system ΣN(S(A)) (or ΣN(S(A))) in an n-dimensional hyperbolic space H n (or spherical space S n) is no more than n + 2 when ΣN(H(A))(N > n) (or ΣN(S(A))(N > n)) are in a sphere (or hyperplane). On the one hand, the Yang-Zhang’s inequalities, the Neuberg-Pedoe’s inequalities and the inequality of the metric addition in an n-dimensional hyperbolic space H n and in an n-dimensional spherical space S n are established by the method of characteristic roots. These are basic inequalities in hyperbolic geometry and spherical geometry. On the other hand, some relative problems and conjectures are brought.

关键词： higher dimensional Euclid space simplex volume radius of circumscribed sphere metric addition Yang-Zhang’s inequality Neuberg-Pedoe’s inequality 51K05

SYNTHESIS OF SOAP-FREE ACRYLIC HYDROSOLS

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chinese Journal of Polymer Science 2002年第6期20卷 531-536页

作者： Li Jia Zong-hui Liu De-qing Wei Chengd Institute of Organic Chemistry chinese academy of sciences,{3., china chinese Acad Sci Chengdu Inst Organ Chem Chengdu 610041 Peoples R China

Poly(methyl methacrylate/ethyl acrylate/acrylic acid) hydrosols were prepared by employing soap-free polymerization, and (acrylic acid/butyl acrylate) oligomer was used as the polymeric surfactant. The effect of reaction condition on the morphology and particle size of the hydrosols was investigated. The minimum amount of acrylic acid in the hydrosols is 2%. The maximum weight average molecular weight (M-w) of polymer that assures soap-free emulsion conversion into hydrosol is about 1.2 x 10(5)-1.3.x 10(5). The particle transforming process was investigated, and an obvious change of particle diameter and morphology was observed.

关键词： hydrosol acrylic resin water-borne resin soap-free polymerization

Nitrogen Mineralization of Prunings of Six N_2-Fixing Hedgerow Species in a Dry Valley of the Jinsha River

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Pedosphere 2002年第1期12卷 25-31页

作者： SUN HUI, TANG YA and ZHAO QIGUO Institute of Soil Science, the chinese academy of sciences, Nanjing, 210008 ({3.) chengdu Institute of Biology, the chinese academy of sciences, chengdu 610041 ({3.) Institute of Soil Science the Chinese Academy of Sciences Chengdu 610041 Ghengdu Institute of Biology the Chinese Academy of Sciences Chengdu 610041 Institute of Soil Science the Chinese Academy of Sciences Nanjing 210008

A litterbag experiment of 12 weeks was conducted to study nitrogenmineralization process of prunings of six nitrogen-fixing hedgerowspecies in a dry valley of the Jinsha River. Prunigns wereincorporated into soil or used as mulch. The results indicated thatpruning N of the six hedgerow species was mineralized fast in thefirst week and then decreased slowly in the rest of the study *** prunings were incorporated into soil, the amount of nitrogenmineralized by the end of the first week accounted for 69.9/100,58.2/100, 54.5/100, 43.0/100, 29.6/100 and 20.6/100 of the total N inprungins of Desmodium rensonii, Tephrosia candida, Leucaenaleucoephala, Albizia yunnanensis, Acacia dealbata, and Acaciamearnsii, respectively.

关键词： contour hedgerow system mineralization N, prunings

PREPARATION OF Fe_3._4/PSt MAGNETIC PARTICLES IN THE PRESENCE OF MAGNETIC FLUID IN ETHANOL/WATER MIXTURE

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chinese Journal of Polymer Science 1999年第2期17卷 129-134页

作者： Xiao-bin Ding Zong-hua Sun Guo-xiang Wan Ying-yan Jiang chengdu Institute of Organic Chemistry, Chinesc academy of sciences,{3., china Institute of Chemistry, chinese academy of sciences, Beijing 100080, china chinese Acad Sci Chengdu Inst Organ Chem Chengdu 610041 Peoples R China chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

Fe_3._4/Polystyrene(PSt) magnetic particles with core/shell structure have been prepared in thepresence of Fe_3._4 magnetic fluid in ethanol/water medium by dispersion polymeriation of styrene. A Fe_3._4particle formation mechanism was proposed. According to this mechanism, the size of particle nuclei isdetermined by the extent of aggregation of Fe_3._4 /oligomer. Magnetic particles with diameter ranging from 5to 200 μm were prepared under different reaction conditions. Some polymerization parameters such as theconcentration of monomer, stabilizer, initiator, and ethanol which affect particle size and size distribution arediscussed and their effect on particle formation are explained by the proposed mechanism.

关键词： Fe_3._4 magnetic fluid Magnetic particle Polystyrene Polymerization Mechanism

SiO/CNTs:A new anode composition for lithium-ion battery

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Science china Chemistry 2009年第12期52卷 2047-2050页

作者： REN YuRong1,2,3.,QU MeiZhen1 & YU ZuoLong1 1 chengdu Institute of Organic Chemistry,chinese academy of {3.,chengdu 610041,china 2 College of Chemistry,Jilin Normal University,Siping 13.000,china 3.Graduate University of chinese academy of {3.,Beijing 10003.,china 1. chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China 2. College of Chemistry Jilin Normal University Siping 136000 China 3. Graduate University of chinese academy of sciences Beijing 100039 China

A new anode composition SiO/CNTs (carbon nanotubes) has been prepared by chemical vapor deposition (CVD) method. The results of scanning electron microscopy (SEM) confirm that CNTs deposit on small SiO particles,form a cage,and enwrap SiO particles tightly. SiO/CNTs anode composition exhibits an initial discharge and charge capacity of 1171 and 789 mAh/g,and maintains a reversible capacity of 500 mAh/g after 80 cycles. The improvement of the cyclic performance for SiO/CNTs composition is related to the maintaining of the electric network during cycling,which benefits from a tight contact between CNTs and SiO particles.

关键词： SiO/CNTs CVD composition anode Li-ion battery

A Proposed Mechanism of Photocatalytic Oxidation of Trichloroethylene in Gas Phase

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chinese Chemical Letters 2000年第1期11卷 31-34页

作者： Gong Hu LI Hu Lan MA Wei Zhu AN (chengdu Institute of Organic Chemistry, The chinese academy of {3., chengdu 610041) chinese Acad Sci Chengdu Inst Organ Chem Chengdu 610041 Peoples R China

GC/MS has been used to identify gas phase products and intermediates formed during the gas phase photocatalytic oxidation of trichloroethylene (TCE) on TiO(2) with low BET surface area. A new byproduct, oxalyl choloride (ClCOCOCl) was detected together with other byproducts such as COCl(2), CHCl(3., DCAC and C(2)HCl(5). Firstly the method of perturbation on the reaction system was conducted. Very little amount of water was carried into the feed gas and subsequent changes were observed. The discussion based on the product distribution changes led to a postulated mechanism consisting of two stages.

关键词： photocatalytic oxidation trichloroethylene product distribution

Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan University Journal of Natural sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2, 3.,HUANG Zhiqin 2, 3. 4 1. The Faculty of Geography and Resources Science, Sichuan Normal University, chengdu 610066, Sichuan, china 2. Institute of Mountain Hazards and Environment, chinese {3. of sciences, chengdu 610041, Sichuan, china 3. Graduate University of the chinese {3. of sciences, Beijing 100049, china 4. Information Center of Land and Resources Department of Sichuan Province, chengdu 610041, Sichuan, china The Faculty of Geography Resources Science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate University of the chinese academy of sciences 100049 Beijing China Information Center of Land Resources Department of Sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992 is extracted from the dynamic polygons of 2002. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 3.°. The areas of steep land cultivated had been slowly reduced from 1992 to 2002. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

RESOLUTION　OF　DL－α－AMINO　ACIDS　ON　A　L－HYDROXY　PROLINE　CHIRAL　PHASE　BY　LIGAND－EXCHANGE　CHROMATOGRAPHY

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chinese Chemical Letters 1995年第5期6卷 383-384页

作者： Tao CHEN Tian Bao HUANG(chengdu Institute of Organic Chemistry, chinese academy of {3., chengdu 610041) chinese Acad Sci Chengdu Inst Organ Chem Chengdu 610041 Peoples R China

A HPLC bonded phase with L- hydroxy proline was prepared by coupling L-hydroxy proline as a chiral selector to silical gel via 3. glycidyloxypropyltrimethoxysilane. The chiral separations of 12 DL - amino acids on the chiral phase were performed and the effects of the chromatographic conditions,the pH of the mobile phase and the column temperature, on the resolution of DL-α-amino acids were studied.

关键词： DL OF RESOLUTION ACIDS AMINO