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REE Geochemistry in the Weathered Crust of Granites, Longnan Area,Jiangxi Province

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Acta Geologica Sinica(English Edition) 1990年第2期64卷 193-209,237页

作者： Wu Chengyu Huang Dianhao Guo Zhongxun institute of Mineral Deposits, chinese academy of Geological {3., Beijing Geological Survey Party of South Jiangxi, Jiangxi Bureau of Geology and Mineral Resources, Ganzhou, Jiangxi JIANGXI BUR GEOL & MINERAL RESOURCES GEOL SURVEY PARTY S JIANGXIGANZHOUPEOPLES R CHINA

Warm and humid climate and gentle hilly topography have provided favourable conditions for the devel-opment of the weathering crust of the granite intrusions in the Longnan area, Jiangxi Province. REE is mostlyconcentrated in an adsorption state in clay in the wholly weathered zone. The rare-earth minerals enriched inthe parent rocks provided the source material for the REE enrichment. Exchangeable REE accounts for48-86%. Extraction experiments and stable isotopic study of clay minerals suggest that the downward infiltra-tion of meteoric water and increasing gradient of pH values have played an important role in the enrichment ofREE during the progressive weathering. Slight fractionation of individual REE can not change their distribu-tion patterns in the profiles. which are inherited from the parent rocks.

关键词： REE Geochemistry in the Weathered Crust of Granites Longnan Area,Jiangxi Province

Spatial patterns in temperature sensitivity of soil respiration in china: Estimation with inverse modeling

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Science china(Life sciences) 2009年第10期52卷 982-989页

作者： ZHOU Tao1,2, SHI PeiJun1,2, HUI DaFeng3.& LUO YiQi4 1 State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, china 2 academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs & Ministry of Education, Beijing 100875, china 3.Department of Biological {3., Tennessee State University, Nashville, TN 3.209, USA 4 Department of botany and Microbiology, University of Oklahoma, Norman, OK 73.19, USA 1. State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China 2. academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs & Ministry of Education Beijing 100875 China 3. Department of Biological sciences Tennessee State University Nashville TN 37209 USA 4. Department of botany and Microbiology University of Oklahoma Norman OK 73019 USA

Temperature sensitivity of soil respiration (Q10) is an important parameter in modeling the effects of global warming on ecosystem carbon release. Experimental studies of soil respiration have ubiquitously indicated that Q10 has high spatial heterogeneity. However, most biogeochemical models still use a constant Q10 in projecting future climate change and no spatial pattern of Q10 values at large scales has been derived. In this study, we conducted an inverse modeling analysis to retrieve the spatial pattern of Q10 in china at 8 km spatial resolution by assimilating data of soil organic carbon into a proc-ess-based terrestrial carbon model (CASA model). The results indicate that the optimized Q10 values are spatially heterogeneous and consistent to the values derived from soil respiration observations. The mean Q10 values of different soil types range from 1.09 to 2.3., with the highest value in volcanic soil, and the lowest value in cold brown calcic soil. The spatial pattern of Q10 is related to environmental factors, especially precipitation and top soil organic carbon content. This study demonstrates that inverse modeling is a useful tool in deriving the spatial pattern of Q10 at large scales, with which being incorporated into biogeochemical models, uncertainty in the projection of future carbon dynamics could be potentially reduced.

关键词： temperature sensitivity Q10 soil respiration global warming inverse analysis

Synchronized oscillation in a modular neural network composed of columns

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Science china(Life sciences) 2005年第1期48卷 6-17页

作者： LI Su, Ql Xianglin, HU Hong & WANG Yunjiu Laboratory for Visual Information Processing, institute of Biophysics, chinese academy of sciences, Beijing 100101, china institute of Computing Technology, chinese academy of sciences, Beijing 100080, china Laboratory for Visual Information Processing Institute of Biophysics Chinese Academy of Sciences Beijing100101 China institute of Computing Technology Chinese Academy of Sciences Beijing100080 China

The columnar organization is a ubiquitous feature in the cerebral cortex. In this study, a neural network model simulating the cortical columns has been constructed. When fed with random pulse input with constant rate, a column generates synchronized oscillations, with a frequency varying from 3.to 43.Hz depending on parameter values. The behavior of the model under periodic stimulation was studied and the input-output relationship was non-linear. When identical columns were sparsely interconnected, the column oscillator could be locked in synchrony. In a network composed of heterogeneous columns, the columns were organized by intrinsic properties and formed partially synchronized assemblies.

关键词： cortical column, synchronized oscillation, Rose-Hindmarsh model.

Fractal properties of patch perimeters in a disturbed montane landscape,Beijing,china

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Journal of Environmental sciences 1999年第2期11卷 68-72页

作者： Ma Ke ming, Fu Bo jie Research Center for Eco Environmental sciences, chinese academy of sciences, Beijing 100085, china

The forest landscape has been highly fragmented in Donglingshan montane region, Beijing, china, where the folding degree of patch perimeters considerately influenced the spatial distribution of biological diversity, therefore the quantitative description to it is very helpful to conservation biology studies. The fractal dimensions of landscape patch perimeters of this region were estimated and compared. The results showed that fractal dimensions of all the landscape types were between 1.00 and 1.58. The fractal dimensions of natural vegetation types were higher than that of artificial vegetation type. Where forests (1 21) and shrubs (1.24) are near to farmland (1.12), so they were both highly disturbed by human activities regarding the smallest mean patch areas. But the grassland (1.58) had the largest mean patch area, its disturbance intensity was the lowest in this region. The fractal dimension of the overall landscape was 1.24, which was near to those of forests and shrubs, and obviously different from those of farmland and grassland. The fractal dimension of the overall landscape was 1.13.in small scales, and that was 1.65 in large scales. Which means that a large number of small area patches had regular perimeters, their fragment degrees were higher; whereas the large area patches had folding perimeters, their fragment degrees were lower, they had smaller patch numbers, however occupied most of the landscape area. Large areas and highly folded perimeters were the main property of the landscape patch in Donglingshan montane region.

关键词： Beijing Dongling montane region landscape fragmentation patch perimeter fractal dimension.

Risk analysis for the highly pathogenic avian influenza in china's mainland using meta-modeling

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Science Bulletin 2010年第36期 4169-4179页

作者： CAO ChunXiang1, XU Min1,3. CHANG ChaoYi1,3. XUE Yong1, ZHONG ShaoBo1, FANG LiQun2, CAO WuChun2, ZHANG Hao1, GAO MengXu1,3. HE QiSheng1,3. ZHAO Jian1,3. CHEN Wei1,3. ZHENG Sheng1,3.& LI XiaoWen1 1 State Key Laboratory of Remote Sensing Science, the institute of Remote Sensing Applications of the chinese academy of sciences, Beijing 100101, china 2 Beijing institute of Microbiology and Epidemiology, State Key Laboratory of Pathogen and Biosecurity, Beijing 100071, china 3.Graduate University of the chinese academy of sciences, Beijing 100049, china

A logistic model was employed to correlate the outbreak of highly pathogenic avian influenza (HPAI) with related environmental factors and the migration of birds. Based on MODIS data of the normalized difference vegetation index, environmental factors were considered in generating a probability map with the aid of logistic regression. A Bayesian maximum entropy model was employed to explore the spatial and temporal correlations of HPAI incidence. The results show that proximity to water bodies and national highways was statistically relevant to the occurrence of HPAI. Migratory birds, mainly waterfowl, were important infection sources in HPAI transmission. In addition, the HPAI outbreaks had high spatiotemporal autocorrelation. This epidemic spatial range fluctuated 45 km owing to different distribution patterns of cities and water bodies. Furthermore, two outbreaks were likely to occur with a period of 22 d. The potential risk of occurrence of HPAI in china's mainland for the period from January 23.to February 17, 2004 was simulated based on these findings, providing a useful meta-model framework for the application of environmental factors in the prediction of HPAI risk.

关键词： highly pathogenic avian influenza meta-modeling remote sensing geographical information system Bayesian maximum entropy logistic regression spatiotemporal autocorrelation

Stereochemistry of the coupling step in photo-S_(RN) 1 reaction

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chinese Journal of Chemistry 1992年第3期10卷 253-261页

作者： WU, Bi-Qi ZENG, Fan-Wen ZHAO, Yong WU, Guo-Sheng Shanghai institute of Organic Chemistry, chinese academy of sciences, Shanghai 20003. Shanghai institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032

The photo-S_(RN) 1 reaction of (+)-camphor and aryl halides was investigated in order to estimate the stereochemistry of the coupling step of aryl radicals with a nucleophile. The ratio of endo to exo products determined by ~1H NMR and CD spectra was found to be 99:1. MNDO calculations of the orbital parameters showed a favorable one-sided overlap of the enolate ion with the SOMO of aryl radical. In addition, fragmentation of (ArX)^- was found to be related to the energy of SOMO of (ArX)^-.

关键词： Ph Stereochemistry of the coupling step in photo-S reaction RN

Beta-Glucosidase Activity in Paddy Soils of the Taihu Lake Region, china

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Pedosphere 2006年第1期16卷 118-124页

作者： WANG Xiao-Chang LU Qin Department of Tea Science Zhejiang University Hangzhou 310029 （China）. institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）

The profile distribution of β-gulcosidase activity in twelve typical paddy soil profiles with high productivity in the Taihu Lake region of china were investigated. Activities of β-gulcosidase in the plow layers were in the range of 52.68- 13..02μg PNP g^-1 soil h^-1 with a mean of 89.22μg PNP g^-1 soil h^-1. However, most plow layers ranged from 70 to 110 μg PNP g^-1 soil h^-1. The profile distribution of β-gulcosidase activity in the 12 soil profiles decreased rapidly with soil depth, with activity at the 60 cm depth only about 10% of that in the surface layers （0-15 cm or 0-20 cm）. In these soil profiles, β-gulcosidase activity was significantly positively correlated with soll organic carbon and arylsulphatase activity. Meanwhile, a significantly negative correlation was shown between β-gulcosidase activity and soil pH.

关键词： beta-gulcosidase activity profile distribution paddy soil Taihu Lake region

Fractal Features and Computer Simulation of Fan-Shaped Sedimentary Bodies in Faulted Basins

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Journal of Earth Science 1998年第3期17卷 50-51页

作者： Zhou Jiangyu Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 510640 Wu Chonglong Faculty of Earth Resources, china University of Geo{3., Wuhan 43.074

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关键词： fan shaped sedimentary body nonlinear dynamics fractal fractal dimension kriging numerical simulation fault basin.

Investigation of integrons/cassettes in antimicrobial-resistant Escherichia coli isolated from food animals in china

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Science china(Life sciences) 2010年第5期53卷 613-619页

作者： SONG Li1,NING YiBao1,SHEN JianZhong2,FAN XueZheng,ZHANG ChunPing1,YANG ChengHuai1 & HAN JianFeng3.1 china institute of Veterinary Drug Control,Beijing 100081,china 2 china Agricultural University,Beijing 100094,china 3.china Center for Disease Control and Prevention,Beijing 100050,china 1. china institute of Veterinary Drug Control Beijing 100081 China2. China Agricultural University Beijing 100094 China3. China Center for Disease Control and Prevention Beijing 100050 China

In this study,3.6 Escherichia coli isolates from food animals collected during the last four decades in china were characterized using antimicrobial susceptibility testing and screening for integrons/*** inhibitory concentration(MIC) testing indicated that the antimicrobial resistance of *** has increased since the *** findings of this study present a warning to veterinary practitioners about the excessive use of antimicrobials,and suggest the necessity for surveillance and control of antimicrobial resistance in veterinary clinical medicine in china.

关键词： E.coli Antimicrobial resistance integron/cassette last four decades