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science china Earth sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2, LUO Xingzhang3, WANG Ju4, JIN Yuanxin4 & WANG Rucheng1 1. Department of Earth sciences, State Key Laboratory of Mineral Deposit research, Nanjing University, Nanjing 210093, china 2. center of Materials Analysis, Nanjing University, Nanjing 210093, china 3. Department of environmental science and Engineering, Nanjing University, Nanjing 210093, china 4. Beijing Geology Institute, Nuclear Industry, Beijing 100029, china Department of Earth sciences State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing China center of Materials Analysis Nanjing University Nanjing china Department of environmental science and Engineering Nanjing University Nanjing china Beijing Geology Institute Nuclear Industry Beijing china

The first results of sorption experiments of U(VI), 234U(VI) and 238U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, china are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in china. The present experimental results show that the maximum U(VI) sorption reached 92% at near-neutral pH and the distribution coefficient (Kd) was 1226 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 234U onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

Genetic analysis and gene mapping of a new rolled-leaf mutant in rice (Oryza sativa L.)

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science china(Life sciences) 2009年第9期52卷 885-890页

作者： SHI YongFeng1,2,CHEN Jie1,LIU WenQiang1,HUANG QiNa1,2,SHEN Bo2,LEUNG Hei3 & WU JianLi1 1 Chinese National center for Rice Improvement/National key Laboratory for Rice Biology,china National Rice research Institute,Hangzhou 310006,china 2 College of Life and environmental sciences,Hangzhou Normal University,Hangzhou 310016,china 3 International Rice research Institute,Metro Manila DAPO Box 7777,Philippines Chinese National center for Rice Improvement/National key Laboratory for Rice Biology China National Rice Research Institute Hangzhou 310006 China College of Life and environmental sciences Hangzhou Normal University Hangzhou 310016 China International Rice research Institute Metro Manila DAPO Box 7777 Manila Philippines

To understand the development of rice leaf blades,we identified a new rolled-leaf mutant,w32,from indica cultivar IR64 through EMS mutagenesis. The mutant showed a stable rolled-leaf phenotype throughout the life cycle. Two F2 populations were developed by crossing w32 to cultivar IR24 and PA64. Genetic analysis showed that the rolled-leaf phenotype was controlled by a single recessive gene. To determine the location of the gene,bulked segregant analysis was carried out using mutant and wild-type DNA pools and 1846 mutant-type F2 individuals derived from the cross w32/PA64 were genotyped to locate the gene on the short arm of chromosome 7. The rolled-leaf gene,tentatively named rl11(t),is likely a new gene as no other rolled-leaf genes have been identified near the region. By developing new SSR and InDel markers,the gene was delimited to a 52 kb region near the end of the short chromosome arm. Further fine mapping and cloning of the gene are currently underway.

关键词： rice (Oryza sativa L.) chemical mutagenesis molecular marker rolled-leaf gene physical map

Impacts of increased atmospheric CO_2 concentration on photosynthesis and growth of micro-and macro-algae

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science china(Life sciences) 2008年第12期51卷 1144-1150页

作者： WU HongYan1, ZOU DingHui1 & GAO KunShan2 1 Marine Biology Institute, Shantou University, Shantou 515063, china 2 State Key Laboratory of Marine environmental science, Xiamen University, Xiamen 361005, china Marine Biology Institute Shantou University Shantou 515063 China State Key Laboratory of Marine environmental science Xiamen University Xiamen 361005 China

Marine photosynthesis drives the oceanic biological CO2 pump to absorb CO2 from the atmosphere, which sinks more than one third of the industry-originated CO2 into the ocean. The increasing atmos-pheric CO2 and subsequent rise of pCO2 in seawater, which alters the carbonate system and related chemical reactions and results in lower pH and higher HCO3- concentration, affect photosynthetic CO2 fixation processes of phytoplanktonic and macroalgal species in direct and/or indirect ways. Although many unicellular and multicellular species can operate CO2-concentrating mechanisms (CCMs) to util-ize the large HCO3- pool in seawater, enriched CO2 up to several times the present atmospheric level has been shown to enhance photosynthesis and growth of both phytoplanktonic and macro-species that have less capacity of CCMs. Even for species that operate active CCMs and those whose photo-synthesis is not limited by CO2 in seawater, increased CO2 levels can down-regulate their CCMs and therefore enhance their growth under light-limiting conditions (at higher CO2 levels, less light energy is required to drive CCM). Altered physiological performances under high-CO2 conditions may cause genetic alteration in view of adaptation over long time scale. Marine algae may adapt to a high CO2 oceanic environment so that the evolved communities in future are likely to be genetically different from the contemporary communities. However, most of the previous studies have been carried out under indoor conditions without considering the acidifying effects on seawater by increased CO2 and other interacting environmental factors, and little has been documented so far to explain how physi-ology of marine primary producers performs in a high-CO2 and low-pH ocean.

关键词： CO2 photosynthesis growth phytoplankton macroalgae

A New Soil Infiltration technology for Decentralized Sewage Treatment:Two-Stage Anaerobic Tank and Soil Trench System

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Pedosphere 2008年第3期18卷 401-408页

作者： YE Chun HU Zhan-Bo KONG Hai-Nan WANG Xin-Ze HE Sheng-Bing School of environmental science and Engineering Shanghai Jiaotong University Shanghai 200230 （China） School of Light Industry and Food Engineering Guangxi University Nanning 530004 （China） research center of Lake Ecological Environment Chinese Research Academy of Environmental Sciences Beijing 100012（China）

The low removal efficiency of total nitrogen （TN） is one of the main disadvantages of traditional single stage subsurface infiltration system, which combines an anaerobic tank and a soil filter field. In this study, a full-scale, two-stage anaerobic tank and soil trench system was designed and operated to evaluate the feasibility and performances in treating sewage from a school campus for over a one-year monitoring period. The raw sewage was prepared and fed into the first anaerobic tank and second tank by 60% and 40%, respectively. This novel process could decrease chemical oxygen demand with the dichromate method by 89%-96%, suspended solids by 91%-97%, and total phosphorus by 91%-97%. The denitrification was satisfactory in the second stage soil trench, so the removals of TN as well as ammonia nitrogen （NH4^＋-N） reached 68%-75% and 96% 99%, respectively. It appeared that the removal efficiency of TN in this two-stage anaerobic tank and soil trench system was more effective than that in the single stage soil infiltration system. The effluent met the discharge standard for the sewage treatment plant （GB18918-2002） of china.

关键词： decentralized treatment nitrogen removal soil trench system subsurface infiltration

research progress in genomics of environmental and industrial microorganisms

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science china(Life sciences) 2009年第1期52卷 64-73页

作者： WANG Lei1,2,LIU Bin1,2 & ZHOU ZheMin1,2 1 TEDA School of Biological sciences and Biotechnology,Nankai University,Tianjin 300457,china 2 Tianjin research center for Functional Genomics and Biochip,Tianjin 300457,china 1. TEDA School of Biological sciences and Biotechnology Nankai University Tianjin 300457 China 2. Tianjin research center for Functional Genomics and Biochip Tianjin 300457 China

Microbes contribute to geochemical cycles in the *** also play important roles in biodegradation and bioremediation of contaminated environments,and have great potential in energy conversion and *** to date,at least 150 genomes of non-pathogenic microbes have been sequenced,of which,the majority are bacteria from various environments or of industrial *** emerging field 'metagenomics' in combination with the high-throughput sequencing technology offers opportunities to discover new functions of microbes in the environment on a large scale,and has become the 'hot spot' in the field of environmental *** genomes of bacteria from various extreme environments,including high temperature,high and low pressure,and extreme acidic regions,have been sequenced by researchers in china,leading to the discovery of metabolic pathways,genetic functions and new enzymes,which are related to the niches those bacteria *** results were published in Nature,PNAS,Genome research and other top international *** the meantime,several groups in china have started 'metagenomics' *** outcomes of these researches are expected to generate a considerable number of novel findings,taking Chinese researchers to the frontier of genomics for environmental and industrial microorganisms.

关键词： genomics microbiology and metagenomics

Risk Assessment of Nitrogen Discharge from a Coastal Watershed

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Pedosphere 2007年第4期17卷 467-474页

作者： CHEN Neng-Wang HONG Hua-Sheng ZHANG Luo-Ping CAO Wen-Zhi State Key Laboratory of Marine environmental science Environmental Science Research Center Xiamen University Xiamen 361005 （China）.

Probabilistic risk assessment （PRA） uses probability theory to quantify the probability of occurrence of an event. In this study, PRA was conducted for the discharge of excess nitrogen （N） from an agricultural （Jiulong River） watershed in Southeast china. Using fault tree analysis, a type of PRA, the probability of occurrence of excess N discharge into the river during a runoff event was evaluated both qualitatively and quantitatively. Land use maps, soil maps, fertilizer use records, and expert opinions were used to determine probabilities of individual events within the fault tree and to calculate the overall probability of excess N discharge during a runoff event. Qualitative analysis showed that the risk of excess N discharge was mainly related to crop and livestock practices in the watershed. Proper management of tillage, fertilizer, and manure was necessary to control N releases. Quantitative assessment results indicated that alternative practices including reduction of fertilization, installation of vegetative strip buffer around the pig farms, and installation of more riparian buffers along the Jiulong River could reduce the likelihood of N discharge through runoff.

关键词： N discharge probabilistic risk assessment runoff watershed

A land surface model incorporated with soil freeze/thaw and its application in GAME/Tibet

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science china Earth sciences 2006年第12期49卷 1311-1322页

作者： HU Heping1, YE Baisheng2, ZHOU Yuhua3 & TIAN Fuqiang1 1. Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, china 2. Cold and Arid Regions environmental and Engineering research Institute, Chinese Academy of sciences, Lanzhou 730000, china 3. Department of Civil Engineering, Massachusetts Institute of technology, USA 1. Department of Hydraulic Engineering Tsinghua University Beijing 100084 China 2. Cold and Arid Regions environmental and Engineering research Institute Chinese Academy of Sciences Lanzhou 730000 China 3. Department of Civil Engineering Massachusetts Institute of Technology USA

Land surface process is of great importance in global climate change, moisture and heat exchange in the interface of the earth and atmosphere, human impacts on the environment and eco- system, etc. Soil freeze/thaw plays an important role in cold land surface processes. In this work the diurnal freeze/thaw effects on energy partition in the context of GAME/Tibet are studied. A sophisti- cated land surface model is developed, the particular aspect of which is its physical consideration of soil freeze/thaw and vapor flux. The simultaneous water and heat transfer soil sub-model not only reflects the water flow from unfrozen zone to frozen fringe in freezing/thawing soil, but also demon- strates the change of moisture and temperature field induced by vapor flux from high temperature zone to low temperature zone, which makes the model applicable for various circumstances. The modified Picard numerical method is employed to help with the water balance and convergence of the numerical scheme. Finally, the model is applied to analyze the diurnal energy and water cycle char- acteristics over the Tibetan Plateau using the Game/Tibet datasets observed in May and July of 1998. Heat and energy transfer simulation shows that: (i) There exists a negative feedback mechanism between soil freeze/thaw and soil temperature/ground heat flux; (ii) during freezing period all three heat fluxes do not vary apparently, in spite of the fact that the negative soil temperature is higher than that not considering soil freeze; (iii) during thawing period, ground heat flux increases, and sensible heat flux decreases, but latent heat flux does not change much; and (iv) during freezing period, soil temperature decreases, though ground heat flux increases.

关键词： land surface model,soil freeze/thaw,GAME/Tibet,simultaneous liquid,vapor and heat transfer.

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

Identification methods of Hammerstein nonelinear CARAR systems

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Identification methods of Hammerstein nonelinear CARAR syste...

STUDY ON THE EFFECTS OF UNSTEADY SHIP TO SHIP INTERACTION BY CFD METHOD

2010 Chinese Control and Decision Conference

作者： Yongsong Xiao,Na Yue,Feng Ding Control science and Engineering research center,Jiangnan University,wuxi,P.R.china 214122

＜正＞A recursive generalized least squares and a generalized stochastic gradient algorithms are developed for Hammerstein nonlinear systems with memoryless nonlinear blocks followed by linear dynamical blocks described by CARAR models（HCARAR models）.The basic idea is to replace the unmeasurable noise terms in the information vectors with their estimates and to compute the noise estimates through different *** simulation results show the performance of the proposed algorithms.

关键词： Recursive Identification Parameter Estimation Hammerstein Models Stochastic Gradient Least Squares

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STUDY ON THE EFFECTS OF UNSTEADY SHIP TO SHIP INTERACTION BY...