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Root Exudates, Rhizosphere Zn Fractions, and Zn Accumulation of Ryegrass at Different Soil Zn Levels

Pedosphere 2007年第3期17卷 389-396页

作者： XU Wei-Hong LIU Huai MA Qi-Fu XIONG Zhi-Ting college of resources and environmental sciences Southwest University Chongqing 400716 （China） college of Plant Protection Southwest University Chongqing 400716 （China） Soil science and Plant Nutrition University of Western Australia Crawley WA 600Y （ Australia） college of resources and environmental sciences Wuhan University Wuhan 430072 （China）

A glasshouse experiment was conducted using a root-bag technique to study the root exudates, rhizosphere Zn fractions, and Zn concentrations and accumulations of two ryegrass cultivars （Lolium perenne L. cvs. Airs and Tede） at different soil Zn levels （0, 2, 4, 8, and 16 mmol kg^-1 soil）. Results indicated that plant growth of the two cultivars was not advérsely affected at soil Zn level ≤ 8 mmol kg^-1. Plants accumulated more Zn as soil Zn levels increased, and Zn concentrations of shoots were about 540 μg g^-1 in Aris and 583.9 μg g^-1 in Tede in response to 16 mmol Zn kg^-1 soil. Zn ratios of shoots to roots across the soil Zn levels were higher in Tede than in Airs, corresponding with higher rhizosphere available Zn fractions （exchangeable, bound to manganese oxides, and bound to organic matter） in Airs than in Tede. Low-molecular-weight （LMW） organic acids （oxalic, tartaric, malic, and succinic acids） and amino acids （proline, threonine, glutamic acid, and aspartic acid, etc.） were detected in root exudates, and the concentrations of LMW organic acids and amino acids increased with addition of 4 mmol Zn kg^-1 soil compared with zero Zn addition. Higher rhizosphere concentrations of oxalic acid, glutamic acid, alanine, phenylalanine, leucine, and proline in Tede than in Airs likely resulted in increased Zn uptake from the soil by Tede than by Airs. The results suggested that genotypic differences in Zn accumulations were mainly because of different root exudates and rhizosphere Zn fractions.

关键词： plant Zn accumulation rhizosphere Zn fractions root exudates ryegrass soil Zn level

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Risk analysis model for landslide mass of high slope in dam area

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science china(Technological sciences) 2008年第S2期51卷 25-31页

作者： GU ChongShi1,2,HE XianFeng3,4,WU ZhongRu1,2 & SU HuaiZhi1,2 1 college of Water Conservancy and Hydropower Engineering,Hohai university,nanjing 210098,china 2 National Engineering Research Center of Water resources Efficient Utilization and Engineering Safety,nanjing 210098,china 3 Yellow River Institute of Hydraulic Research,Zhengzhou 450003,china 4 Embankment Security Defect Prevention and Control Engineering Research Center of MWR,Zhengzhou 450003,china 1. college of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China 2. National Engineering Research Center of Water resources Efficient Utilization and Engineering Safety Nanjing 210098 China 3. Yellow River Institute of Hydraulic Research Zhengzhou 450003 China 4. Embankment Security Defect Prevention and Control Engineering Research Center of MWR Zhengzhou 450003 China

In order to identify the threat of reservoir bank landslide to dam safety and reduce the risk of dam failure,impact factors of the landslide are *** concept of landslide risk degree is put forward to measure the threat of landslide to dam *** monotony of the landslide risk assessment function which changes with different affecting factors is analyzed *** on gene automatic programming,a data mining model of the landslide risk assessment function is constructed combined with impact factors of reservoir bank landslide on dam *** the assessment function of landslide risk has been excavated and established according to practical project information,which provides a valuable reference for analyzing the impact of landslide on dam risk.

关键词： landslide dam failure risk landslide risk

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Enantioselective separation and zebrafish embryo toxicity of insecticide beta-cypermethrin

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Journal of environmental sciences 2010年第5期22卷 738-743页

作者： Chao Xu,Wenqing Tu,Chun Lou,Yingying Hong,Meirong Zhao Research Center of environmental science,college of Biological and environmental Engineering,Zhejiang university of Technology,Hangzhou 310032,china. [a] Research Center of environmental science College of Biological environmental Engineering Zhejiang University of Technology Hangzhou 310032 China

Enantioselectivity of chiral pollutants is receiving growing concern due to the difference in toxicology and environment fate between *** this study,enantiomers of insecticide beta-cypermethrin （beta-CP） were separated on selected chiral column by HPLC,and the toxicity of enantiomers was evaluated using the zebrafish embryo-larval *** enantiomers of beta-CP were baseline separated on Chiralcel OD and Chiralpak AD columns and detected by circular dichroism （CD） at 236 *** separation could be achieved at lower temperature （e.g.,20°C） and with lower levels of polar *** enantiomers were obtained on Chiralcel *** CD spectra of enantiomers were *** comparing the elution order with a previous similar study,the absolute configuration of beta-CP enantiomers was *** individual enantiomers were used in zebrafish embryo test,and the results showed that beta-CP enantioselectively induced yolk sac edema,pericardial edema and crooked *** 1R-cis-αS and 1R-trans-αS enantiomers showed strong developmental toxicities at concentration of 0.1 mg/L,while the 1S-cis-αR and 1S-trans-αR induced no malformations at higher concentration （e.g.,0.3 mg/L）.The results suggest that the enantioselective toxicological effects of beta-CP should be considered when evaluating its ecotoxicological effects.

关键词： beta-cypermethrin enantioselectivity zebrafish embryo chiral separation

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Soil Macropore Structure Characterized by X-Ray Computed Tomography

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Pedosphere 2003年第4期13卷 289-298页

作者： FENGJie ZHANGJia-Bao ZHUAn-Ning BIJing-Wei InstituteofSoilscience theChineseAcademyofSciencesNanjing210008China collegeofWaterresourcesandEnvironment HohaiUniversityNanjing2100g8China

Undisturbed soil core with many macropores and disturbed soil core with onlyone macropore (diameter is 10 mm) were probed by X-ray computed tomography (CT). The size, number,shape and continuity of macropores in the transverse and vertical sectionsof soil were characterizedusing CT scanning images. The probability densities of macropores in the transverse section of soilcore exhibited a logarithmic P distribution. Results indicated that CT scanning was a promisingnondestructive method for characterizing macropores in soils.

关键词： CT scanning distribution image macropores

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分类表编制技术标准发展态势研究

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图书馆工作与研究 2008年第2期 30-36页

作者：黄建年侯汉清南京农业大学信息科技学院南京农业大学信息科技学院江苏南京210095

随着网络信息资源的迅速增加,对分类表的需求也与日俱增,分类表编制技术受到了越来越多的关注,美英等国率先行动,分别制定或者修订了Z39.19标准及BS 8723标准。这些标准重新诠释了基本概念、倡导分面分析方法、强调科学选择类目、界定... 详细信息

随着网络信息资源的迅速增加,对分类表的需求也与日俱增,分类表编制技术受到了越来越多的关注,美英等国率先行动,分别制定或者修订了Z39.19标准及BS 8723标准。这些标准重新诠释了基本概念、倡导分面分析方法、强调科学选择类目、界定和处理等级关系、推广类目注释、重视显示方式等。与此类似,我国亦积极关注国外最新进展,陆续制定或者修改了一系列相关标准,如GB7026、GB/T 7027等,并参照国外标准完善现有分类表。为了适应网络信息分类的需要,相关机构还积极探讨了网络信息分类标准的编制技术。

关键词：图书分类法分类表编制技术标准受控词表

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FINE SILT PARTICLE PATHLINE OF DREDGING SEDIMENT IN THE YANGTZE RIVER DEEPWATER NAVIGATION CHANNEL BASED ON EFDC MODEL

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Journal of Hydrodynamics 2010年第6期22卷 760-772页

作者： XIE Rui WU De-an YAN Yi-xin ZHOU Hai college of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China Shanghai Institute of Waterways Shanghai 200120 China

Based on the environmental Fluid Dynamics Code （EFDC）, a three-dimensional baroclinic model for lower reaches of the Yangtze River, Yangtze River Estuary, Hangzhou Bay and the adjacent sea areas was established with the sigma-coordinate in the vertical direction and the orthogonal curvilinear coordinates in the horizontal direction. The fine silt particle tracers were injected during different tides with the calibrated three-dimensional numerical model in the Yangtze River Estuary to simulate the migration tracks of the tracers in the following three days, and thereby study the migration behavior of the fine silt particles of dredged sediment after dumping at different locations in the navigation channel in the Yangtze River Estuary. The study shows that the particle paths of the tracer particles basically migrate to the open sea along the middle axis of river course in the form of reciprocating oscillation, the migration and diffusion directions of tracer particles are basically parallel to the navigation channel in guide levee, similar to long belt distribution, and the tracer particles migrate to the southeast out of the guide levee. The particle which is on the southern and northern sides enter groin and cross the navigation channel in the process of movement, and is easy to deposit in the navigation channel. The migration tracks of the particles released at different layers are basically similar at the same release station, but specifically different, varying at different cross sections. The result can be used for the choice and evaluation of dredging schemes in the Yangtze River Deepwater Navigation Channel.

关键词： deepwater channel EFDC model tracer fine silt particles

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Research on Indicator System of Regional Eco-efficiency:A Case Study of Chengyang District

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Chinese Journal of Population,resources and Environment 2006年第4期4卷 54-58页

作者： Zhou Zhenfeng1,2,Sun Lei2,Sun Yinglan2 1.college of resources&Environment,Laiyang agricultural college,Qingdao,Shandong 266109,china 2.School of environmental science and Engineering,Ocean university of china,Qingdao,Shandong 266003,china college of resources & Environment Laiyang Agricultural College Qingdao Shandong 266109 China School of environmental science and Engineering Ocean University of China Qingdao Shandong 266003 China School of Environmental Science and Engineering Ocean University of China Qingdao Shandong 266003 China School of Environmental Science and Engineering Ocean University of China Qingdao Shandong 266003 China

Eco-efficiency is a valuable tool for managing and solving issues involving resource consumption and pollution emission in current production *** the popularity of the term"eco-efficiency"in business,limited attention has been paid to measuring and reporting regional eco-efficiency for local government policy *** on the concept and method of eco-efficiency,an indicator system of regional eco-efficiency is established in this *** indicator system comprises 22 indicators,which are divided in to three categories including socio-economic development,resources consumption, environmental *** a promising statistical technique, principle component analysis is used to set the weight of indicators which attempts to calculate the eco-efficiency indices of Qingdao's Chengyang *** results show that the eco-efficiency of Chengyang District has clearly improved 35.1% with small fluctuation from 1995 to ***-economic development index and resources consumption index also represent obvious increasing *** correlation coefficient between soci-economic development index and resources consumption index is 0.979,which means the social progress and economic growth of Chengyang District depend on an extravagant consumption of *** environmental pressure index increased slowly before 1997 and declined gradually after 1997,due to more attention being paid to environmental protection by local government in recent *** District still keeps the traditional economic development mode with a high consumption and high production,so the emphases of future development should put on improving the improving the efficient use of natural resources and promoting environmental management *** results show that the indicators system of regional eco-efficiency is a promising method to quantitatively evaluate resources and environmental efficiency and provide an effective decision-making support for local governments.

关键词： regional eco-efficiency indicator system Ecoefficiency Synthetic Index (ESI) Principle Component Analysis (PCA)

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Edaphic factors determining variation of two ecotypes of Leymus chinensis in North china

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Progress in Natural science:Materials International 2006年第11期16卷 1150-1155页

作者： ZHOU Chan~1 and YANG Yunfei~2**(1. MOE Key Laboratory of environmental Change and Natural Disasters, college of resources science and Technology, Beijing Normal university, Beijing 100875, china 2. Key Laboratory of Vegetation Ecology, Ministry of Education, Institute of Grassland science, Northeast Normal university, Changchun 130024, china) [a]MOE Key Laboratory of environmental Change and Natural Disasters College of Resources Science and Technology Beijing Normal University Beijing China [b]Key Laboratory of Vegetation Ecology Ministry of Education Institute of Grassland Science Northeast Normal University Changchun China

To identify ecotypic variation of L. chinensis, the physiological characteristics and environmental factors were measured and assessed for grey-green and yellow-green ecotypes of L. chinensis grown in the salt-alkalized and aeolian sandy soils. Although both ecotypes presented a similar salt-alkaline tolerance under the experimental conditions, they differed in several aspects. The L. chinensis grown in the aeolian sandy soils had higher water potential and chlorophyll content and lower proline content in their leaves than those grown in the salt-alkalized habitat, and the grey-green ecotype of L. chinensis in both types of soils had higher water potential, chlorophyll and proline contents than the yellow-green ecotype. Besides, grey-green ecotypes had higher salt-alkaline tolerance than the yellow-green ecotype. The stepwise regression analysis showed that soil conductance and pH value were the main ecological factors affecting the physiology of L. chinensis. From the natural distribution of the two ecotypes, we considered that salt-alkaline in the soils is the leading factor in determining ecotypic variation of L. chinensis. The two ecotypes were first named grey-green and yellow-green ecotypes respectively.

关键词： L.chinensis ecotype adaptability variation ecological factor salt-alkaline in soil.

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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 university, Beijing 100037, china college of resources Environment and Tourism, Capital Normal university, Beijing 100037, china Beijing Key Laboratory for resources Environment and Geography Information System, Beijing 100037, china) [a]college of Life science Capital Normal University Beijing China [b]college of resources Environment and Tourism Capital Normal University Beijing China [c]Beijing Key Laboratory for resources Environment and Geography Information System Beijing 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 BL21 (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 BL21 (DE3) pLysS through IPTG induction and the 56.0 kD protein was obtained.

关键词： Cocksfoot mottle virus sequence analysis prokaryotic expression.

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Heat treatment of novel low-carbon multi-alloyed anti-wear marine steel

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Progress in Natural science:Materials International 2011年第3期21卷 254-261页

作者： Jing-hua JIANG~(1,2),Qiu-yue WANG~1,Ai-bin MA~(1,2),Jun SHI~1,Liu-yan ZHANG~1, Hui-dong YANG~(2,3),Fu-min LU~2,Qi ZHOU~2 1.National Engineering Research Center of Water resources Efficient Utilization and Engineering Safety, Hohai university,nanjing 210098,china 2.college of Mechanics and Materials,Hohai university,nanjing 210098,china 3.Department of Mechanical and Aerospace Engineering,North Carolina State university, Raleigh,North Carolina 27695-7919,USA [a] National Engineering Research Center of Water resources Efficient Utilization and Engineering Safety Hohai University Nanjing 210098 China [b] college of Mechanics and Materials Hohai University Nanjing 210098 China [c] Department of Mechanical and Aerospace Engineering North Carolina State University Raleigh North Carolina 27695-7919 USA

A low-carbon anti-wear steel,multi-alloyed with Si-Cr-Mn-Al-Ni-Mo-（Nb,RE）,was designed for vane pumps of ships. The novel cast steel after various heat treatments was characterized by microstructure observations and mechanical properties measurement in order to achieve an optimal process correlated with good abrasive resistance for a long marine *** scanning calorimetry and hardness analyses deduced a complete austenitizing temperature of 1 000℃,based on the alloying element homogenization and defective structure elimination without grain *** optimal austempering process（austenitized at 1 000℃,quick cooled for holding at 350℃for 1.5 h and then air-cooled to room temperature） produced a uniform mixture structure of fine carbide-free aciculate bainites and few lath martensites,resulting in the tensile strength increase of 34%and impact toughness increase of 50%compared with that of the as-cast *** abrasive wheel tests show that the austempered steel has good wear resistance with a mass-loss rate of 170 mg/（km·cm2） under applied load of 70 N in acidic *** new grade steel （containing anti-corrosion elements of Cr and rare earth） can find wide application in marine engineering,with further enhanced comprehensive properties via melting process improvement.

关键词： abrasive resistance carbide-free bainite marine steel mechanical performance heat treatment

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