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Chinese Science Bulletin 2011年第7期56卷 685-690页

作者： LI GuiAn, ZHU TingLiang, DENG ZhongXun, ZHANG YaJuan, JIAO Fei & ZHENG HaiRong College of Physics and Information Technology, shaanxi normal university, xi’an 710062, china College of Physics and Information Technology Shaanxi Normal University Xi’an China

A copper-doped silica composite aerogel with high specific surface area was prepared using a sol-gel method at ambient pressure. A drying control chemical additive (DCCA) N,N-dimethylformamide (DMF) was introduced to the composite sol of tetraethyl orthosilicate (TEOS) and copper nitrate (Cu(NO3.2·3.2O) during the synthesizing process. The influence of the preparation conditions including Cu loading, catalyst concentration and heat treatment on the structure of copper-doped silica was investigated. The results showed that the obtained aerogel particles were uniformly distributed. The pore diameter was in a range of 2 to 15 nm. Heavier Cu loading benefited the formation of CuO crystalline, and reduced the specific surface area and pore diameter. When the catalyst concentration was high, the aggregation of Si-O network was reduced with the increase of it. The composite aerogel exhibited a good thermal stability after the heat treatment at high temperature.

关键词：复合气凝胶铜掺杂凝胶结构合成条件 Si02 常压正硅酸乙酯溶胶凝胶法

Reference value of old people's hematocrit and geographical factors

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Journal of Geographical Sciences 2000年第4期10卷 75-81页

作者： Ge Miao, Ren Zhiyuan, Yang Qingsheng, Wei Haiyan, Yin Shuyan, Jin xiuchan (Dept. of geography, shaanxi normal university, xi’an 710062,{3.)

This paper is written in order to provide a scientific basis for a unified standard of the reference value of Chinese healthy old people's hematocrit. It studies the relationship between the reference values of healthy old people's hematocrit, tested according to the Wintrobe Laws and five geographical factors. It is found that the altitude is the most important factor affecting the reference value of old people's hematocrit. As the altitude gradually increases, the reference value of their hematocrit also increases, the relationship is quite significant. By using the method of stepwise regression analysis, two multivariate regression equations are deduced:1=50.2+0.0024.X1-0.053.0}3.0.3.8X4.0.003.3.5±2.2, 2=4..5+0.0023.X1-0.0600X3.0.260X4.0.003.0}X5±2.1. If the geographical index values in a particular area in china are known, the reference value of old people's hematocrit in this area can be established by means of the regression equations. Furthermore, according to the dependent relationship of the reference value of old people's hematocrit on geographical factors, china can be divided into six regions: Qinghai-Tibet, Plateau, Southwest, Northwest, Southeast, North and Northeast.

关键词： hematocrit reference value geographical factors regression analysis

LONGTIME BEHAVIOR FOR THE ACTIVATOR-INHIBITOR MODEL

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Systems Science and Mathematical Sciences 2000年第3期13卷 285-291页

作者： WU Jianhua(Department of Mathematics, shaanxi normal university, xi’an 710062, china)HUANG Aixiang(Department of Mathimatics, xi’an Jiaotong {3., xi’an 71004., china) 陕西师范大学数学系陕西西安 710062 西安交通大学数学系陕西西安

The paper first discusses the longtime behavior of the activator-inhibitor model, the existence of the maximal attractor is given. Then using the mathematical induction and the properties of linear semigroup, the regularity result for the maximal attractor is obtained. Next, it is proved that its Hausdorff or fractal dimension is ***, further estimates are verilied by Rothe’s inequality and fractional operators, and the existence of inertial manifold is then proved.

关键词： Maximal attractor estimate of dimension inertial manifold activatorinhibitor model

Study Progress and Trends of Strategic Environmental Assessment in china

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Chinese Journal of Population,Resources and Environment 2009年第2期7卷 76-82页

作者： Cai Chunmiao1,2, 3. Shang Jincheng4.1. Northeast Institute of geography and Agroecology, Chinese Academy of Sciences, Changchun Jilin 13.012, china 2. Department of geography, Harbin university, Harbin Heilongjiang 150086, china 3. Graduate School of Chinese Academy of Sciences, Beijing 10003., china 4. College of Urban and Environmental Science, Northeast normal university, Changchun Jilin 13.024. china Northeast Institute of geography and Agroecology Chinese Academy of Sciences Changchun Jilin 130012 China Department of geography Harbin University Harbin Heilongjiang 150086 China Graduate School of chinese Academy of Sciences Beijing 100039 China College of Urban and Environmental Science Northeast Normal University Changchun Jilin 130024 China

Strategic environmental assessment (SEA) in china has developed rapidly since it was introduced into china in the 1990s. Chinese government promulgated the Environmental Impact Assessment Law of china (hereinafter referred to as the EIA Law) in 2002. In this law, it is stipulated clearly that regional and sector plans should be assessed. Through investigating materials and analyzing literatures, this article analyses the practical and academic study achievements of SEA in china that have been achieved since the EIA Law was implemented, probes into the current situation of the main level of SEA in china-plan EIA, then summarizes the development characteristics, and eventually, puts forward the development trends of SEA in china. The research conclusions can offer the foundations for comprehending systematically the progress of SEA in china.

关键词： strategic environmental assessment plan environmental impact assessment china study progress characteristics development trends

GLOBAL SOLUTIONS AND BLOW UP FOR ACTIVATOR INHIBITOR MODEL

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Systems Science and Mathematical Sciences 1998年第3期11卷 238-244页

作者： ZHANG Quande(Department of Mathematics, shaanxi normal university, xi’an 710062, china)LI Kaitai(Research Center for Applied Mathematics, xi’an Jiaotong {3., xi’an 71004., china)

This paper deals with the existence and nonexistence of global positive solutions of initial and boundary value problem for the general activator-inhibitor model In this paper, we do not restrict ourselves to the initial data 1/uo, 1/uo ∈L∞(Ω). We prove that there exist glolal solutions if 0 ≤ u0 ≤ u0 and they will blow up in finite time if 0 ≤ v0 ＜ u0 whether u0, v0 are small or large.

关键词： Global solutions blow up of solution activator-inhibitor model

Effect of Ryegrasses on Soil Runoff and Sediment Control

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Pedosphere 2008年第1期18卷 131-136页

作者： ZHOU Zheng-Chao SHANGGUAN Zhou-Ping College of Tourism and Environmental Sciences Shaanxi Normal University Xi'an 710062 (China) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling Shaanxi 712100 (China) Northwest A & F university Yangling Shaanxi 712100 (China)

Living plants and plant roots can reduce runoff and soil erosion. Using a rain simulator, a series of soil erosion experiments were conducted to study the influence of living roots and canopies of ryegrasses （Lolium perenne L.） during the growing season on sediment yields and runoff of a silt loam soil. The results indicated that during the growing season, decrements in runoff and sediment yields increased with time. Sediment yields （τ^2 = 0.999） and decrements in runoff （τ2 = 0.94.） were closely related to the root surface area density. The contributions of roots and canopies of ryegrasses to the reductions in runoff and sediment yields were different. Canopies usually contributed more to the runoff decrement than the roots, whereas roots contributed up to 96% of the decrease in sediment yields in the late stage of the growing season.

关键词： canopy root runoff ryegrass sediment yield

Note about Fixed Points of Scott Continuous Self-Mappings

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Journal of Mathematical Research and Exposition 2011年第1期31卷 187-190页

作者： xiao Yong xi1,2,Yong Ming LI3.1.College of Mathematics and Information Science,shaanxi normal university,shaanxi {4.,P.R.china 2.College of Mathematics Science,Xuzhou normal university,Jiangsu 221009,P.R.china 3.College of Computer Science,shaanxi normal university,shaanxi {4.,P.R.china College of Mathematics and Info'rmatio'n Science Shaanxi Normat University Shaanxi 710062 College of Computer Science Shaanxi Normal University Shaanxi 710062

It is discussed in this paper that under what conditions, for a continuous domain L, there is a Scott continuous self-mapping f ： L → L such that the set of fixed points fix（f） is not continuous in the ordering induced by L. For any algebraic domain L with a countable base and a smallest element, the problem presented by Huth is partially solved. Also, an example is given and shows that there is a bounded complete domain L such that for any Scott continuous stable self-mapping f, fix（f） is not the retract of L.

关键词： Scott continuous fixed points stable mapping.

Relationship between reference value (Wintrobe) of Chinese people's erythrocyte sedimentation rate (ESR) and geographical factors

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Journal of Geographical Sciences 1999年第2期9卷 181-186页

作者： GEMiao YAN Yan REN Zhi-yuan GUO Cai-ling YUE Da-peng YIN Shu-yan (Department of geography,shaanxi normal {3.,{4., china)

In order to provide a scientific basis for laying out a unified standard of the reference value (Wintrobe) of Chinese people's erythrocyte sedimentation rate (ESR). this paper studies the relationship between the reference values (Wintrobe) of Chinese healthy people's ESR, and the test is done according to the Wintrobe Laws and five geographical factors. It is found that the altitude is the modt important factor affecting the reference value (Wintrobe) of Chinese people's ESR. As altitude increases gradually, the reference value (Wintrobe) of people's ESR decreases accordingly, the correlation is quite obvious. By using the method of regression analysis, two multivariate regression equations and ten univariate regression equations are deduced If the geographical index values in a particular area are known, the reference value (Wintrobe) of Chinese people's ESR of this region can be established by means of the regression equations. Furthermore, according to the dependent relationship of the reference value (Wintrobe) of Chinese people's ESR on geographical *** can be divided into sin districts: Qinghai-Tibet, Southwest. Northwest. Southeast, North and Northeast china.

关键词： erythrocyte sedimentation rate (ESR), reference value geographical elements altitude hemorheology

Retrieving crop leaf area index by assimilation of MODIS data into a crop growth model

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Science china Earth Sciences 2010年第5期53卷 721-730页

作者： WANG DongWei1,2,3. WANG JinDi1,2 & LIANG ShunLin4.1 State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Beijing normal university and Institute of Remote Sensing Applications, CAS, Beijing 100875,{3. 2 School of geography, Beijing Key Laboratory of Environmental Remote Sensing and Digital City, Beijing normal university, Beijing 100875,{3. 3.Haihe River Water Conservancy Commission, Tianjin 3.0170,{3. 4.Department of geography, university of Maryland, College Park, MD 2074., USA State Key Laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing Applications CAS Beijing China School of geography Beijing Key Laboratory of Environmental Remote Sensing and Digital City Beijing Normal University Beijing China Haihe River Water Conservancy Commission Tianjin China Department of geography University of Maryland College Park USA

Leaf area index (LAI) is an important parameter in monitoring crop growth. One of the methods for retrieving LAI from remotely sensed observations is through inversion of canopy reflectance models. Many model inversion methods fail to account for variable LAI values at different crop growth stages. In this research, we use the crop growth model to describe the LAI changes with crop growth, and consider a priori LAI values at different crop growth stages as constraint information. The key approach of this research is to assimilate multiple canopy reflectance values observed at different growth stages and a priori LAI values into a coupled crop growth and radiative transfer model sequentially using a variational data assimilation algorithm. Adjoint method is used to minimize the cost function. Any other information source can be easily incorporated into the inversion cost function. The validation results show that the time series of MODIS canopy reflectance can greatly reduce the uncertainty of the inverted LAI values. Compared with MODIS LAI product at Changping and Shunyi Counties of Beijing, this method has significantly improved the estimated LAI temporal profile.

关键词： inversion leaf area index crop growth model time series MODIS

Wave Solutions for the GinzburgLandau-BBM Equations (I)

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Communications in Nonlinear Science and Numerical Simulation 1998年第4期3卷 218-221页

作者： Murong JIANG and Yawei TIAN(Department of Mathematics, Yunnan university, Kunming 650091, china)(Graduate School of china Academy of Engineering and Physics, P.O.Box 2010 Beijing100081, china)(Computer Department,{4., xi’an 710062, Department of Mathematics Yunnan University Kunming 650091 China Graduate School of china Academy of Engineering and Physics P.O.Box 2010 Beijing 100081 China Computer Department Shanxi Normal University Xi'an 710062 China

In this paper, the stability of plane wave solutions for the GinzburgLandau-BBM equations are considered. When the coefficients are suitably constrained,these waves are stable.

关键词： stability the Ginzburg- Landau- BBM equations plane wave solutions