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Pedosphere 2008年第6期18卷 699-706页

作者： YANG Li-Lin ZHANG Fu-Suo MAO Ren-Zhao JU Xiao-Tang Cai Xiao-Bu LU Ya-Hai College of Resources and Environmental Sciences China Agricultural University Beijing 100094 （China） center for agricultural Resources Research Chinese Academy of Sciences Shijiazhuang 050021 （China） College of agricultural and Animal Husbandry Tibet University Linzhi 860000 （China）

A comparative study was conducted to determine the NH4+ and NO3. concentrations in soil profiles and to examine the net nitrogen (N) mineralization and nitrification in adjacent forest, grassland, and cropland soils on the Tibetan Plateau. Cropland soil showed significantly higher inorganic N concentrations in soil profiles compared with forest and grassland soils. NO3. -N accounted for 70%–90% of inorganic N in cropland soil, while NH4+ -N was the main form of inorganic N in forest and grassland soils. The average net N mineralization rate at 0–2. cm depth was approximately twice in cropland soil (1.48 mg kg-1 d-1) as high as in forest (0.83.mg kg-1 d-1) or grassland soil (0.72.mg kg-1 d-1). Cropland showed strong net nitrification, with the net rate almost equal to the total net N mineralization. Urea addition stimulated soil respiration, particularly in forest soil. Most urea-N, however, remained as NH4+ in forest and grassland soils, while NO3. was the main form of inorganic N to increase in cropland soil. Higher rates of net nitrification in cropland soils suggest that land use change on the Tibetan Plateau may lead to high N losses through nitrate leaching.

关键词： land use change microbial biomass nitrification nitrogen mineralization

Ecological rebuilding and land reclamation in surface mines in Shanxi Province, China

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Journal of Environmental Sciences 2000年第4期12卷 486-497页

作者： MIAO Ze wei 1, BAI Zhong ke 2. GAO Lin 1 (1. Research center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China E\|mail: miaozewei@*** 2. Department of Soil Science, Shanxi agricultural {2. Taigu, 03 中科院生态环境研究中心北京 1 0 0 0 85 山西师范大学山西临汾 0 3 0 80 1

It is well known that the mining industry produces a large amount of derelict land, and causes pollution of water loss and soil erosion as well as other environmental damage in China. As land is under pressure in China, it is now policy to restore or reclaim land despoiled by mining, the aim being to develop sustainable and healthy arable land ecosystems. This paper outlines the principles and approaches of ecological restoration, which have been adopted in Shanxi Province with reference to three typical surface mines. In the research, the principles of ecological engineering and ecological succession are considered as the critical theories of ecological restoration in mine degraded land. Meanwhile, the paper made a comparative research on main links of ecological rebuilding in three surface mines in Shanxi Province, which include new land construction, treatment of toxic substances, control of soil erosion, fertility management, irrigation, ecological planning and the establishment of legislation systems. As the research demonstrated, for successful restoration, new land construction is the fundamental framework, but it must be integrated with ecological engineering including ecological planning, the control of soil erosion and vegetation establishment and ecosystem creation in order to optimise land productivity and soil fertility. In addition, the establishment of the legislation systems and organization of administration are also indispensable aspects of ecological rebuilding in mined land.

关键词： ecological restoration land reclamation open-pit mine

Modeling the intracellular dynamics for Vif-APO mediated HIV-1 virus infection

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Chinese Science Bulletin 2010年第22期55卷 2329-2340页

作者： WANG Yi1,2.& LAI LuHua1,3.1 center for Theoretical Biology, Peking {2., Beijing 100871, China 2.School of Physics, Peking {2., Beijing 100871, China 3.BNLMS, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, Peking {2., Beijing 100871, China center for Theoretical Biology Peking University Beijing 100871 China School of Physics Peking University Beijing 100871 China BNLMS State Key Laboratory for Structural Chemistry of Unstable and Stable Species College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

The viral infectivity factor (Vif) was found to be essential for controlling HIV-1 virus infectivity. It targets cellular antiviral proteins in APOBEC family (APO) to trigger its fast degradation and inhibits APO packaging into nascent virion. In the present study, we propose a mathematical model to quantitatively study the intracellular dynamics of these typical virus-host interactions. Four sets of published experimental data were compared with simulation results to justify the model. Systematic parameter sensitivity and perturbation analysis showed that parameters related to APO are crucial to the infectivity of newly synthesized HIV-1 virus. Interestingly, we discovered that the synthesis rate of the viral structure protein Gag and the required number per nascent virion are optimized to achieve high virion production with minimal level of packaged APO, and large portion of model parameters are beneficial to virus only within a relatively small range. Furthermore, minor variations in several parameters related to viral protein Tat, the activator of viral RNA synthesis, were found to induce switch-like behaviors on both incorporated Vif and APO. These findings may provide new insights for understanding the high mutation rate of HIV-1 virus and its latency, as well as help identify key targets for therapeutic design.

关键词：病毒感染载脂蛋白 HIV 细胞内动力学抗病毒蛋白建模介导

Stomatal movement in response to long distance-communicated signals initiated by heat shock in partial roots of Commelina communis L.

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Science China(Life Sciences) 2006年第1期49卷 18-25页

作者： YANG Songjie1, HUANG Conglin2. WU Zhongyi2. HU Jianfang3. LI Tianzhong3. LIU Shigui1 & JIA Wensuo3.1. School of Life Science, Sichuan university, Chengdu 6.006., China 2. Beijing Agriculture and Forestry Academy, Beijing Agriculture and Biotechnology {3., Beijing 10089, China . 3. State Key Laboratory of Plant Physiology and Biochemistry, College of Agronomy and Biotechnology, China agricultural university, Beijing 100094, China School of Life Science Sichuan University Chengdu 610064 China Beijing Agriculture and Forestry Academy Beijing Agriculture and Biotechnology Center Beijing 10089 China State Key Laboratory of Plant Physiology and Biochemistry College of Agronomy and Biotechnology China Agricultural University Beijing 100094 China

The systematic or long-distance signal transmission plays crucial roles inanimal lives. Compared with animals, however, much less is known about the roles of long-distancesignal communication in plant lives. Using the model plant Commelina communisL, we have probed theroot to shoot communication mediated by heat-shock signals. The results showed that a heat shock of5 min at 40°C in partial roots, i.e. half or even 1/4 root system, could lead to a significantdecrease in stomatal conductance. The regulation capability depends on both heat shock temperatureand the amount of root system, i.e. with higher temperature and more roots stressed, the leafconductance would decrease more significantly. Interestingly, the stomatal regulation by heat shocksignal is in a manner of oscillation: when stomata conductance decreased to the lowest level withinabout 3. min, it would increase rapidly and sometimes even exceed the initial level, and afterseveral cycles the stomata conductance would be finallystabilized at a lower level. Feeding xylemsap collected from heat-shocked plants could lead to a decrease in stomata conductance, suggestingthat the heat shock-initiated signal is basically a positive signal. Further studies showed thatheat shock wasnot able to affect ABA content in xylem sap, and also, not able to lead to a decreasein leaf water status, which suggested that the stomatal regulation was neither mediated by ABA norby a hydraulic signal. Heat shock could lead to an increase in xylemsap H_2._2.content, andmoreover, the removal of H_2._2.by catalase could partially recover the stomatal inhibition by xylemsap collected from heat-shocked plants, suggesting that H_2._2.might be able to act as one of theroot signals to control the stomatal movement. Due to the fact that heat-shock and drought areusually two concomitant stresses, the stomatal regulation by heat-shock signal should be ofsignificance for plant response to stresses. The observation for the stomatal regulation in an

关键词： root signal, leaf conductance, heat shock, long-distance, signal transmission, abscisic acid.

Synthesis of todorokite by refluxing process and its primary characteristics

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Science China Earth Sciences 2004年第8期47卷 760-768页

作者： FENG Xionghan1, LIU Fan1, TAN Wenfeng1, LIU Xiangwen2.& HU Hongqing1 1. College of Resources and Environment, Huazhong agricultural university, Wuhan 4{2.070, China 2. Testing center, China university of Geosciences, Wuhan 4{2.074, China 1. College of Resources and Environment Huazhong Agricultural University 430070 Wuhan China 2. Testing center China University of Geosciences 430074 Wuhan China

Single phase and well-crystallined todorokite were synthesized by heating and refluxing process from birnessite as a precursor. The average chemical composition of the synthesized todorokites by refluxing for 8 h and for 2. h was Mg0.19MnO2.11(H2.)1.15 and in0.17-MnO2.10(H2.)0.88, respectively. The crystallinity of the todorokite increased and no other phase was produced with increasing refluxing period. The synthesized todorokites have the same morphologies and the similar structural characteristics with the natural todorokites and hydro-thermally synthesized samples. The chemical compositions of the synthetic tordorokites by refluxing process are close to those of todorokites synthesized by hydrothermal process, except a higher average oxidation state of Mn for the former.

关键词： todorokite,birnessite,manganese oxide,refluxing,hydrothermal,synthesis.

Influence of Formate on Bioactivity Material-thuringiensin Synthesized by Bacillus thuringiensis YBT-03.

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Journal of Wuhan university of Technology(Materials Science) 2008年第5期23卷 691-693页

作者：王志喻子牛 College of Bioengineering Hubei University of Technology State Key Laboratoy of agricultural Microbiology National Engineering Research center for Microbial Posticides Huazhong Agricultural University

The biological method to synthesize thuringiensin and the influence of formate on thuringiensin biosynthesis were investigated. Addition of 1.00 g/L formate to growth medium of bacillus thuringiensis YBT-03. resulted in significant enhancements in productions of citrate, α -ketoglutarate, intracellular adenine and thuringiensin. These results demonstrate that added formate attends metabolism of cell, facilitates carbon metabolic flux in tricarboxylic acid cycle and hexose monophosphate pathway. As a carbon source, formate facilitates cell growth, increases glucose consumption and enhances the ability of cell to synthesis adenine analogues, and subsequently thuringiensin. Thuringiensin production rate significantly enhanced from 6.44 to 8.46.mg·g^-1 · h and transformation ratio from glucose to thuringiensin increased by 43.3.%.

关键词： bacillus thuringiensis precursor formate thuringiensin

Pathways of birnessite formation in alkali medium

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Science China Earth Sciences 2005年第9期48卷 1438-1451页

作者： FENG Xionghan1, TAN Wenfeng1, LIU Fan1, HUANG Qiaoyun1 & LIU Xiangwen2.1. College of Resources and Environment, Huazhong agricultural university, Wuhan 4{2.070, China 2. Testing center, China university of Geosciences, Wuhan 4{2.074, China 1. College of Resources and Environment Huazhong Agricultural University 430070 Wuhan China 2. Testing center China University of Geosciences 430074 Wuhan China

Birnessite is a common weathering and oxidation product of manganese-bearing rocks. An O2.oxidation procedure of Mn(OH)2.in the alkali medium has been used to synthesize birnessite. Fast and powder X-ray diffraction (XRD), transmission electron microscopy (TEM), electron diffraction (ED), energy dispersed X-ray analysis (EDAX), infrared spectroscopy (IR) techniques and chemical composition analysis, Eh-pH equilibrium diagram approaches were employed to investigate the reaction process and pathways of birnessite formation. Results showed that the process of the birnessite formation could be divided into four stages: (1) forma- tion stage for hausmannite and feitknechtite, (2. stage of transformation of hausmannite and feitknechtite to buserite, (3. buserite crystal growing stage, and (4) stage of conversion of buser- ite into birnessite. Mn(OH)2.was mainly present as amorphous state only for a short initial time of oxidation reaction. In the oxidation process, buserite formed following two pathways by recrys- tallization after dissolution of the intermediates, and the transformations of the minerals de- pended on the Eh determined by the dissolved O2.concentration on their surfaces. The results are fundamental in further exploration on the mechanism of birnessite formation in the alkali medium. A great practical significance would also be expected with respect to the areas of mate- rial sciences.

关键词： birnessite, pathway of formation, reaction process, Eh-pH diagram, hausmannite, feitknechtite.

National 2.00' GPS control network of China

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Progress in Natural Science:Materials International 2007年第8期17卷 983-987页

作者： Yang Yuanxi~(1**) Tang Yingzhe~1 Chen Chuanlu~2.Wang Min~3.Zhang Peng~4 Wang Xiaorui~2.Song Lijie~5 Zhang Zusheng~6.(1.Xi'an Research Institute of Surveying and Mapping,Xi'an 710054,China 2.Geodetic Data Processing {2.,Xi'an 710054,China 3.{2. of Earthquake Analysis and Prediction,China Seismological Bureau,Beijing 10003.0}China 4.National Geomatics {2. of China,Beijing 100044,China 5.Institute of Surveying and Mapping,Zhengzhou {3. of Information Engineering,Zhengzhou 450052.China 6.First Crustal Deformation Monitoring {2.,China Seismological Bureau,Tianjin 3.0180,China) [a]Xi' an Research Institute of Surveying and Mapping Xi' an China [b]Geodetic Data Processing center Xi'an China [c]center of Earthquake Analysis and Prediction China Seismological Bureau Beijing China [d]National Geomatics center of Chinna Beijing China [e]Institute of Surveying and Mapping Zhengzhou University of Information Engineering Zhengzhou China [f]First Crustal Deformation Monitoring center China Seimological Bureau Tianjin China

An accurately unified national GPS network with more than 2.00 stations,named"National 2.00' GPS Control Net- work",signed the epoch 2.00.0,has been established by integrating the existing six nationwide GPS networks of China set up by differ- ent departments with different *** paper presents the characteristics of the existing GPS networks,summarizes the strategies in the integrated adjustment of the GPS network,including functional model,stochastic model as well as the adjustment principle modifi- *** modifying the adjustment strategies according to the characteristics of the existing GPS networks and under the support of the IGS stations,the accuracy of the integrated national GPS network is greatly *** datum differences among the sub networks disappear,the systematic error influences are weakened,and the effects of the outliers on the estimated coordinates and their variances are *** is shown that the average standard deviation for the horizontal component is smaller than 1.0 cm,the vertical component is smaller than 2.0 cm,and the three-dimensional (3.D) position of geocenter coordinates is smaller than 3.0 *** exterior checking ac- curacy for the 3.D position is averagely better than 1.0 cm.

关键词： GPS control network adjustment systematic errors robust estimation variance component estimation coordinate system

Seabed Classification Using BP Neural network Based on GA

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Acta Oceanologica Sinica 2003年第4期22卷 523-531页

作者： Yang Fanlin1, Liu Jingnan2.1. GPS Engineering Research center, Wuhan university, Wuhan 4{2.079, China. 2. Presidential Secretariat, Wuhan university, Wuhan 4{2.079, China Wuhan Univ GPS Engn Res Ctr Wuhan 430079 Peoples R China

Side scan sonar imaging is one of the advanced methods for seabed study. In order to be utilized in other projects, such as ocean engineering, the image needs to be classified according to the distributions of different classes of seabed materials. In this paper, seabed image is classified according to BP neural network, and. Genetic Algorithm is adopted in train network in this paper. The feature vectors are average intensity, six statistics of texture and two dimensions of fractal. It considers not only the spatial correlation between different pixels, but also the terrain coarseness. The texture is denoted by the statistics of the co-occurrence matrix. Double Blanket algorithm is used to calculate dimension. Because a uniform fractal may not be sufficient to describe a seafloor, two dimensions are calculated respectively by the upper blanket and the lower blanket. However, in sonar image, fractal has directivity, i. e. there are different dimensions in different direction. Dimensions are different in acrosstrack and alongtrack, so the average of four directions is used to solve this problem. Finally, the real data verify the algorithm. In this paper, one hidden layer including six nodes is adopted. The BP network is rapidly and accurately convergent through GA. Correct classification rate is 92.5 % in the result.

关键词： BP network co-occurrence matrix fractal classification genetic algorithin

Complete multiple round quantum dense coding with quantum logical network

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Chinese Science Bulletin 2007年第9期52卷 1162-1165页

作者： LI ChunYan1,2.LI XiHan1,2.DENG FuGuo1,2.3.ZHOU Ping1,2.& ZHOU HongYu1,2.3.1 Key Laboratory of Beam Technology and Material Modification of Ministry of Education,Beijing Normal {2.,Beijing 100875,China 2.Institute of Low Energy Nuclear Physics,and Department of Material Science and Engineering,Beijing Normal {2.,Beijing 100875,China 3.Beijing Radiation center,Beijing 100875,China Key Laboratory of Beam Technology and Material Modification of Ministry ofEducation Beijing Normal University Beijing 100875 China

We present a complete multiple round quantum dense coding scheme for improving the source ca-pacity of that introduced recently by Zhang et al. The receiver resorts to two qubits for storing the four local unitary ope... 详细信息

关键词：量子通信多重量子紧凑编码量子逻辑网络量子纠缠