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Cloning, sequencing and expression of the coat protein gene of Cocksfoot mottle virus

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Progress in Natural Science:Materials International 2007年第2期17卷 222-225页

作者： DONG Zhi, GUO Xiaoyu, ZHANG Hailong and ZHANG Feiyun ( college of Life Science, Capital normal {2., Beijing 100037, china college of resources environment and Tourism, Capital normal {2., Beijing 100037, china Beijing Key Laboratory for resources environment and Geography Information System, Beijing 100037, china) college of Life Science Capital Normal University Beijing 100037 China college of resources {2. and Tourism Capital Normal University Beijing 100037 China Beijing Key Laboratory for resources environment and Geography Information System Beijing 100037 China

The coat protein (CP) gene of Cocksfoot mottle virus (CfMV) was amplified by RT-PCR and inserted into expression vector pGEX-4T-1, and the resulting plasmid was designated as pGEXCfMV-JANCP. The fusion protein GST-CP was expressed in BL2. (DE3) pLysS after IPTG induction. The results of SDS-PAGE and Western blot analysis showed that the CfMV-CP gene was efficiently expressed in E. coli BL2. (DE3) pLysS through IPTG induction and the 56.0 kD protein was obtained.

关键词： Cocksfoot mottle virus sequence analysis prokaryotic expression.

Cluster based node scheduling method for wireless sensor networks

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Science china(Information Sciences) 2012年第4期55卷 755-764页

作者： WANG Lei 1,2.WEI RuiZhong 2.& TIAN ZiHong 2.3 1 college of Software,Hunan university,Changsha 410082.{2. 2.Department of Computer Science,Lakehead university,Thunder Bay P7B 5E1,Canada 3 Mathematics and Information Science college,hebei normal university,shijiazhuang 050016,{2. college of Software Hunan University Changsha China Department of Computer Science Lakehead University Thunder Bay Canada Mathematics and Information Science college Hebei Normal University Shijiazhuang China

By researching on the node scheduling problem of m-covered and connected sensor networks,a new concept of two-hops-cluster is proposed in this paper,and based on it,a new distributed node scheduling algorithm THCNS for allocating all nodes in the sensor network into k(k≤m) different groups {0,1,...,k 1} is designed,without requiring location *** algorithm guarantees that each group to be connected and maintains the coverage ratio with high *** analysis and simulation results show that it has better performance than previous randomized scheduling scheme,and can prolong the lifetime of the sensor network effectively.

关键词： node scheduling lifetime wireless sensor network two-hops-cluster

Definition of Measure-theoretic Pressure Using Spanning Sets

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Acta Mathematicae Applicatae Sinica 2004年第4期 709-718页

作者： Lian Fa HE college of Mathematics and Information Science,hebei {2. university,shijiazhuang 050016,P.R.chinaJin Feng LV hebei normal university of Science & Technology,Qinhuangdao 066004,P.R.china Li Na ZHOU college of Mathematics and Information Science,hebei {2. university,shijiazhuang 050016,P.R.china

We introduce a new definition of measure-theoretic pressure for ergodic measures of con-tinuous maps on a compact metric *** definition is similar to those of topological pressureinvolving spanning *** an application,for C(α>0) diffeomorphisms of a compact manifold,we study the relationship between the measure-theoretic pressure and the periodic points.

关键词： Ergodic measure Measure-theoretic pressure Spanning set

Scenario simulation and forecast of land use/cover in northern china

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Chinese Science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2.3 & HE ChunYang 3 1 college of Geographical Science, Chongqing normal {2., Chongqing 400047, china 2.college of resources and environmental Science, Chongqing {2., Chongqing 400044, china 3 college of resources Science & Technology, Beijing normal {2., Beijing 100875, china college of Geographical Science Chongqing Normal University Chongqing China college of resources and {2.al Science Chongqing University Chongqing China college of resources Science & Technology Beijing Normal University Beijing China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 30 years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学

THE EXISTENCE OF SOLUTIONS OF NONLINEAR BOUNDARY VALUE PROBLEMS INVOLVING THE p-LAPLACIAN OPERATOR IN L^s-SPACES

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Journal of Systems Science & Complexity 2005年第4期18卷 511-521页

作者： WEI Li (School of Mathematics and Statistics, hebei university of Economics and Business, {2. 050061, china Institute of Applied Mathematics and Mechanics, Ordnance Engineering college, {2. 050003, china. ZHOU Haiyun (Institute of Applied Mathematics and Mechanics, Ordnance Engineering college, {2. 050003, china Institute of Mathematics and Information Science, hebei normal university, shijiazhuang 050016, china. School of Mathematics and Statistics Hebei University of Economics and Business 河北 Shijiazhuang 050061

By using the perturbation theories on sums of ranges of nonlinear accretive mappings of Calvert and Gupta, we study the abstract results on the existence of a solution u ∈ L^s （Ω） of nonlinear boundary value problems involving the p-Laplacian operator, where 2. s〈＋∞, and 2./N＋1 〈 p ≤ 2.for N（≥ 1） which denotes the dimension of R^N. To obtain the result, some new techniques are used in this paper. The equation discussed in this paper and our methods here are extension and complement to the corresponding results of L. Wei and Z. He.

关键词： Maximal monotone operator accretive mapping hemi-continuous mapping p-Laplacian operator nonlinear boundary value problem.

Preparation and properties of nanosize MnZn ferrite from δ-FeOOH

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Rare Metals 2006年第Z1期25卷 466-470页

作者： HAO Shunli WANG Xin WEI Yu Wang Yongming Liu Chunjing School of Material and Engineering Hebei University of Technology Tianjin 300130 China 　 College of Chemistry Hebei Normal University Shijiazhuang 050016 China 　　

Ferrous ion was transformed into feroxyhyte (δ-FeOOH) by oxidation. Then, manganese sulfate and zinc sulfate in some ratio were added to the feroxyhyte solution. The co-precipitation was boiling reflux conditions sometime under constant stirring. The nanosize MnZn ferrite powder was formed. The mechanism of preparation of the nanosize MnZn ferrite was discussed, and the formation of feroxyhyte which was playing a key role during the process was mentioned. The properties of powder was tested by means of X-ray diffraction, transmission electron microscopy and vibrating sample magnetometer. The results show that the samples of spherical particles about 2. nm, which have characteristics of ferrimagnetism, has larger saturation magnetization, but the remanent magnetization and coercivity are comparatively smaller. The spinel MnZn ferrite nanosize powder was successfully prepared from δ-FeOOH at low temperature, with low-carbon steel and peroxide as main material.

关键词： nanosize MnZn ferrite feroxyhyte preparation characterization

Denitrification in Chongming east tidal flat sediment, Yangtze estuary, china

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Science china Earth Sciences 2006年第10期49卷 1090-1097页

作者： WANG Dongqi1,2. CHEN Zhenlou1,3, XU Shiyuan1,2. HU Lingzhen1 & WANG Jun1,2.1. college of resources & {2., East china normal university, Shanghai 2.0062. china 2. State Key Laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics, East china normal university, Shanghai 2.0062. china 3. Key Laboratory of Geographical Information Science of Ministry of Education,East china normal university,Shanghai 2.0062. china college of resources & {2. East China Normal University Shanghai China State Key Laboratory of Estuarine and Coastal Sediment Dynamics and Morphodynamics East China Normal University Shanghai China Key Laboratory of Geographical Information Science of Ministry of Education East China Normal University Shanghai China

From July 2.03 to July 2.04, samples were collected on Chongming Island east tidal flat every two months. The research showed that the nitrous oxide (N2.) production rate was very low in the water, Chongming east tidal flat (CM) sediment was the N2. source of the water. Sediment N2. natural production rate was between -0.08 and 1.74 μmolN·m-2.h-1. N2. natural production rate was higher in the summer. The difference of the N2. natural production rate in the different tidal flats, the correlation between the N2. natural production rate and the denitrification rate, and those with the temperature and DO indicate that middle tidal flat sediment denitrification was the main process of the N2. production, while in the low tidal flat sediment, the production of the N2. came from several processes of the nitrogen cycling. Tidal flat sediment denitrification reaction was stronger in summer and winter but relatively lower in the late autumn and early spring. Seasonal change of the sediment denitrification rate was wide, from 1.12.to 33.34 μmolN·m-2.h-1. Temperature, DO and the coactions of them had the prominent effect on the tidal flat sediment denitrification.

关键词： Yangtze estuary, tidal flat sediment, denitrification, nitrous oxide, effect factor.

The Adjustment on Service Structure and Strategic Orientation of Postal Service

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The Journal of china Universities of Posts and Telecommunications 2004年第Z1期11卷 88-93页

作者： WANG Wei-min~1, SUN Hao~2. XU Ru-wei~1 1.shijiazhuang Post and Telecommunication Technical college, shijiazhuang 05002., P.R. china 2.hebei normal university, shijiazhuang 050016, P.R. china shijiazhuang Post and Telecommunication Technical college Shijiazhuang 050021 P.R. China hebei normal {2. Shijiazhuang 050016 P.R.China

The service structure of china post is not match the postal resources structure, Core service is not stressed. Therefore, the postal service must be reorganized and Adjusted according to the market needs. This article classify post service into five catalogues, proposes the strategic orientation of each catalogues and analyses the interior structure of different postal service.

关键词： core power postal core service postal service structure strategic orientation

Study on Human Capital Valve Quantity Model and Investment Featuers

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Chinese Journal of Population,resources and environment 2005年第1期3卷 49-54页

作者： Chen Peian, Li Yujiang & Li Zhen Population, resources and environment {2., Shandong normal university, Jinan Shandong 2.0014, china Population Resources and Environment College Shandong Normal University Jinan Shandong 250014 China

In this paper, human capital is considered a kind of goods in terms of investment. Basic consumption and profit margin are the two important components of human capital goods value. Compared with that of the material capital, the human capital consumption has the following features. The importance of human capital investment determined by the supply-demand mechanism, is growing gradually; The course of investment and return takes a long period of time; Human capital is characterized by strong technicality and weak negotiability; The investment profit margin is changeable and discriminating.

关键词： human capital value measure profit margin