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Predicting bioconcentration factor values of organic pollutants based on medv descriptors derived QSARs

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science china Chemistry 2007年第5期50卷 587-592页

作者： CUI ShiHai1,2, YANG Jing1, LIU ShuShen2,3 & WANG LianSheng2 1 college of Chemistry and Environment, Nanjing Normal university, Nanjing 210097, china 2 State Key Laboratory of Pollution Control and resources Reuse, School of the Environment, Nanjing university, Nanjing 210093, china 3 Key Laboratory of Yangtze Aquatic Environment, Ministry of Education, college of environmental science and Engineering, Tongji university, Shanghai 200092, china college of Chemistry and Environment Nanjing Normal University Nanjing China State Key Laboratory of Pollution Control and resources Reuse School of the Environment Nanjing University Nanjing China Key Laboratory of Yangtze Aquatic Environment Ministry of Education College of Environmental Science and Engineering Tongji University Shanghai China

The molecular electronegativity-distance vector (MEDV) is employed todescribe the chemical structure of organic *** linear relationships between themolecular descriptors and BCF values are developed by best subset regression and partial leastsquare regression *** main structural factors influencing the bioactivities are -CH2,-X,-Cnot 2 and q2_(LOO) present good estimation ability and stabilityof *** prediction power for external samples is validated by the model developed from thetraining set.

关键词： POPs, BCF, MEDV, QSAR

New stylophorans(Echinodermata) from the Upper Cambrian of Guangxi,South china

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science china Earth sciences 2008年第2期51卷 181-186页

作者： HAN NaiRen1 & CHEN GuiYing1,2 1 Department of resources and environmental Engineering, Guilin university of Technology, Gulin 541004, china 2 Faculty of Earth sciences, china university of Geoscience, Wuhan 430074, china Department of resources and environmental Engineering Guilin University of Technology Gulin China Faculty of Earth sciences China University of Geoscience Wuhan China

This paper describes for the first time the cornute stylophorans (Echinodermata) in china. The new material came from the Guole Formation of the Furongian (Late Cambrian) in the Guole area of Jingxi, Guangxi Province, South china. These new cornute specimens are preserved in situ and found along with well-preserved trilobites and brachiopods. One new species, Phyllocystis jingxiensis sp. nov., is proposed to accommodate these unusual materials. The new species is defined by the small, heart-shaped theca with the frame composed of ten narrow, smooth and thick marginal plates, three adoral plates and distinctive zygal and aulacophore. Both supracentrals and infracentrals are polygonal-outlined. The marginal plate M1' on the inferior face extends posteriorly to form zygal that possesses a broadened proximal end and the proximal portion joining with the conjunction between M4 and M5 on the inferior face. Aulacophore comprises ten segments at its proximal part and is conical at the middle part (named stylocone). Its distal portion is rather long and bears conspicuous ambulacrum grooves. Tectals are horizontally arranged on superior face and obliquely arranged on inferior face. Both cothurnopore and anal pyramid are vaguely seen on the right anterior corner and the extremity of theca's superior face.

关键词： Phyllocystis Stylophora Echinodermata Cambrian Guangxi South china

Use of the modified viral satellite DNA vector to silence mineral nutrition-related genes in plants: silencing of the tomato ferric chelate reductase gene, FRO1, as an example

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science china(Life sciences) 2008年第5期51卷 402-409页

作者： HE XiuXia1,2,JIN ChongWei1, LI GuiXin3, YOU GuangYi4, ZHOU XuePing3 & ZHENG ShaoJian4 1 Key Laboratory for environmental and Ecosystem Health of the Ministry of Education, college of environmental and Resource science, Zhejiang university, Hangzhou 310029, china 2 college of Life science, Changchun university of science and Technology, Changchun 130022, china 3 Institute of Biotechnology, Zhejiang university, Hangzhou 310029, china 4 State Key Laboratory of Plant Physiology and Biochemistry, college of Life science, Zhejiang university, Hangzhou 310058, china Key Laboratory for environmental and Ecosystem Health of the Ministry of Education College of Environmental and Resource Science Zhejiang University Hangzhou China college of Life science Changchun University of Science and Technology Changchun China Institute of Biotechnology Zhejiang University Hangzhou China State Key Laboratory of Plant Physiology and Biochemistry College of Life Science Zhejiang University Hangzhou China

Virus-induced gene silencing (VIGS) is potentially an attractive reverse-genetics tool for studies of plant gene function, but whether it is effective in silencing mineral nutritional-related genes in roots has not been demonstrated. Here we report on an efficient VIGS system that functions in tomato roots using a modified viral satellite DNA (DNAmβ) associated with Tomato yellow leaf curl china virus (TYLCCNV). A cDNA fragment of the ferric chelate reductase gene (FRO1) from tomato was inserted into the DNAmβ vector. Tomato roots agro-inoculated with DNAmβ carrying both a fragment of FRO1 and TYLCCNV used as a helper virus exhibited a significant reduction at the FRO1 mRNA level. As a consequence, ferric chelate reductase activity, as determined by visualization of the pink FeBPDS3 complex was significantly decreased. Our results clearly demonstrated that VIGS system can be employed to investigate gene function associated with plant nutrient uptake in roots.

关键词： virus-induced gene silencing roots ferric chelate reductase

Kinetic analysis of waste activated sludge hydrolysis and short-chain fatty acids production at pH 10

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Journal of environmental sciences 2009年第5期21卷 589-594页

作者： FENG Leiyu, YAN Yuanyuan, CHEN Yinguang State key Laboratory of Pollution Control and resources Reuse, School of environmental science and Engineering, Tongji university, Shanghai 200092, china. State key Laboratory of Pollution Control and resources Reuse School of Environmental Science and Engineering Tongji University Shanghai 200092 China

The accumulation of short-chain fatty acids （SCFAs）, a preferred carbon source for enhanced biological phosphorus removal microbes, was significantly improved when waste activated sludge （WAS） was fermented at pH 10. The kinetics of WAS hydrolysis and SCFAs production at pH 10 was investigated. It was observed that during WAS anaerobic fermentation the accumulation of SCFAs was limited by the hydrolysis process, and both the hydrolysis of WAS particulate COD and the accumulation of SCFAs followed first-order kinetics. The hydrolysis and SCFAs accumulation rate constants increased with increasing temperature from 10 to 35℃, which could be described by the Arrhenius equation. The kinetic data further indicated that SCFAs production at pH 10 was a biological process. Compared with the experiment of pH uncontrolled （blank test）, both the rate constants of WAS hydrolysis and SCFAs accumulation at 20℃ were improved significantly when WAS was fermented at pH 10.

关键词： waste activated sludge hydrolysis short-chain fatty acids kinetics alkaline pH

Calculation of maximum ground movement and deformation caused by mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 562-569页

作者： LI Pei-xian1, 2, TAN Zhi-xiang1, 2, DENG Ka-zhong1, 2 1. Key Laboratory for Land Environment and Disaster Monitoring of State Bureau of Surveying and Mapping, china university of Mining and Technology, Xuzhou 221116, china 2. Jiangsu Key Laboratory of resources and environmental Information Engineering, china university of Mining and Technology, Xuzhou 221116, china Key Laboratory for Land Environment and Disaster Monitoring of State Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China Jiangsu Key Laboratory of resources and environmental Information Engineering China University of Mining and Technology Xuzhou 221116 China

In order to know the maximum mining ground deformation of arbitrary surface point, directions of the maximum surface tilt, curvature,horizontal displacement and horizontal deformation caused by multi-working faces were deduced based on probability integral method. The distribution forms of surface deformations in all direction φ∈[0, 2π] were obtained and also equations of maximum deformations were given based on calculation of mining ground deformation in direction φ. A mining subsidence analysis system was developed with VB6.0. The system implements the probability integral mining subsidence prediction with direct integration method, and it can avoid errors of arbitrary shaped working face subdivision of traditional method, and accuracy of mining subsidence prediction can be improved with the direct integral method. The system implements the contour chart and profile chart and also data analysis automation by manipulation of the SURFER kernel function and it complements the defect of existing subsidence prediction software. Calculation of maximum deformations caused by multi-working faces mining in a coal mine of Xuzhou, china was shown as application example. Engineering application indicates that maximum deformation of mining ground surface can be calculated and analyzed by the system. The research provides a theoretical basis and calculation tool for mining subsidence prediction and analysis.

关键词： mining subsidence probability integral method movement and deformation system development

Ramet population ecology of Panicum virgatum in the field–Competitively random growth of ramets and foraging behavior of ramet populations

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Progress in Natural science:Materials International 2008年第7期18卷 901-906页

作者： Xinguo Yang a,*, Tianlong Wu b, Xu Chengb a college of resources and environmental sciences, china Agricultural university, Beijing 100193, P.R. china b college of Agriculture and Biotechnology, china Agricultural university, Beijing 100193, P.R. china college of resources and environmental sciences China Agricultural University Beijing 100193 P.R. China college of Agriculture and Biotechnology China Agricultural University Beijing 100193 P.R. China

The authors investigated the heterogeneous size patterns and dynamic growth of the ramet population of Panicum virgatum, a clonal caespitose plant, limited to the space occupied by a ramet bunch and the time of the ramet yearly life cycle, to understand the ecology of clonal caespitose plants in the field, where the ramet bunch generally consisted of more than one genet. Dynamic life tables for ramet populations were established by the replacement of living ramets at the present time with "dead" ones in past time. These tables revealed stable coexisting patterns of isometric and allometric growing processes of ramets in mass and height respectively, which approximately followed the historic trajectory of a density-independent population. The ecology of clonal caespitose plants is further discussed based on the competitively random growth of ramet individuals, including the scale of foraging behavior. In the field, the ramet population ecol- ogy of switchgrass may be a statistical result of competitively random growth of ramet individuals. The foraging behavior of a ramet population could then be presented as a process in which ramet individuals competed with each other for light and grew randomly, while at the same time a relatively stable dynamic growth pattern was apparent at the level of the ramet population, and the functional leaves were placed properly in time and space.

关键词： Caespitose clone Ramet population Panicum virgatum Life table Phenotypic plasticity Foraging behavior

Bio-Mobilization of Potassium from Clay Minerals: Ⅱ. By Ectomycorrhizal Fungi

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Pedosphere 2000年第4期10卷 347-354页

作者： YUAN LING, WANG ZHIHUI, FANG DEHUA, SHUN HONG and HUANG JIANGUO (college of resources and Environment, Southwest Agricultural university, chongqing 400716 china)

Ectomycorrhizal fungi, including Cenococcum geophilum SIV (Cg SIV), and Pisolithus tinctorius 2144 (Pt 2144), 441 (Pt 441) and XC1 (Pt XC1), were cultured in Pachlewski liquid medium with H2KPO4,KCl- saturated vermiculite and mica as K sources, respectively, to investigate the mechanism of K absorption and mobilization by the fungi. Fungal growth rate, K absorption and mobilization varied significantly among the fungal species. Faster growth and greater K accumulation in Pt XC1 than Pt 2 144, Pt 441 and Cg siv were observed. Ectomycorrhizal fungi depressed HCl-soluble K in minerals after successive extractions by water and NH4OAc. Ratio of the total amount of K, including water-, NH4OAc- and HCI-soluble K, lost from substrates to the K accumulated in fungal colonies was less than 60%. These reveal that the ectomycorrhizal fungi could utilize K in interlayer and structural pools, which are usually unavailable for plants in short period. Large differences in the depletion of K in interlayer and structural pools by fungi were observed at fungal harvest. Taking into account the nutrient absorption by ectomycorrhizal fungi in symbionts and the direct contact between hyphae and soils, the fungi species colonized on the root surfaces seemed to be related to the effectiveness of mycorrhizas to utilize K in soils. Ectomycorrhizal fungi differed in the efflux of protons and oxalate. Pt XC1 was observed to have greatest ability to effuse protons and oxalate among the fungi adopted in the experiment. Furthermore, the higher the concentrations of protons and oxalate in the liquid culture solutions, the larger the depletion of K in interlayer and structural pools in minerals by fungi. Protons could replace interlayer K and chelation of oxalate with Fe and Al in crystal lattice could cause weathering of clay minerals. So, protons and oxalate produced by ectomycorrhizal fungi might play an important role in K mobilization in these two pools.

关键词： ectomycorrhizal fungi K proton and oxalate

Chiral Mn(Ⅲ) salen complex immobilized on imidazole-modified mesoporous material via co-condensation method as an effective catalyst for olefin epoxidation

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science china Chemistry 2009年第9期52卷 1417-1422页

作者： LOU LanLan1, YU Yi1, YU Kai2, JIANG Shu1, DONG YanLing1 & LIU ShuangXi1 1 Institute of New Catalytic Materials science, college of Chemistry, Nankai university, Tianjin 300071, china 2 college of environmental science and Engineering, Nankai university, Tianjin 300071, china Institute of New Catalytic Materials science College of Chemistry Nankai University Tianjin China college of environmental science and Engineering Nankai University Tianjin China

An imidazole modified mesoporous material has been prepared through a co-condensation procedure and adopted to covalently anchor chiral Mn(Ⅲ) salen complex. The active centers in the as-synthesized catalyst were presented in the form of ionic species. The results of XRD, FTIR, DRUV-Vis, and N2 sorp-tion confirmed the successful immobilization of chiral Mn(Ⅲ) salen complex inside the channels of the modified support and the maintenance of the mesoporous structure of parent support in the immobi-lized catalyst. This heterogeneous catalyst exhibited comparable catalytic activity and enantioselectiv-ity to those of the homogeneous counterpart in the asymmetric epoxidation of unfunctionalized olefins. Furthermore, notably high turnover frequencies have been obtained over this heterogeneous catalyst for the relatively short reaction time and low catalyst amount, due in part to the ionic property as well as the uniform distribution of the active centers.

关键词： imidazole-functionalized mesoporous material chiral Mn(Ⅲ) salen complex co-condensation asymmetric epoxidation unfunctionalized olefins

Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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science china Earth sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2,3, ZHANG Yili1, BAI Wanqi1, LIU Yanhua4, BAO Weikai5, LIU Linshan1, 2 & ZHENG Du1 1. Institute of Geographic sciences and Natural resources Research, Chinese Academy of sciences, Beijing 100101, china 2. Graduate School of the Chinese Academy of sciences, Beijing 100039, china 3. college of resources and Environment, Southwest Agricultural university, chongqing 400716, china 4. The Ministry of science and Technology, P. C. china, Beijing 100862, china 5. Chengdu Institute of Biology, Chinese Academy of sciences, Chengdu 610041, china Institute of Geographic sciences and Natural resources Research Chinese Academy of Sciences Beijing China Graduate School of the Chinese Academy of sciences Beijing China college of resources and Environment Southwest Agricultural University Chongqing China The Ministry of science and Technology P. C. China Beijing China Chengdu Institute of Biology Chinese Academy of Sciences Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2000 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2000, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.43%. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2000, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.