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2D/3D-QSAR comparative study on mutagenicity of nitroaromatics

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Science china Chemistry 2005年第3期48卷 246-252页

作者： WANG Xiaodong1, LIN Zhifen2, YIN Daqiang1, LIU Shushen1 & WANG Liansheng1 1. State Key laboratory of Pollution Control and Resources Reuse, School of the environment at nanjing university, nanjing 210093, china 2. Key laboratory of Tropical marine environmental Dynamics, South china Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301,china 1. State Key laboratory of Pollution Control and Resources Reuse School of the Environment at Nanjing University 210093 Nanjing China 2. Key laboratory of Tropical marine environmental Dynamics South China Sea Institute of Oceanology Chinese Academy of Sciences 510301 Guangzhou China

Nitroaromatics are typical toxic organic pollutants and are ubiquitous in environment with diverse structures. They are widely used in many industries and formed during many natural and anthropogenic processes. Most of these pollutants are potentially carcinogenic and the as-sessment and prediction of the mutagenicity of nitroaromatics are of great interest. In this paper the structure-mutagenicity relationships of 219 nitroaromatics are investigated by molecular or-bital theory based classic structure-activity relationships and comparative molecular field analysis (CoMFA). A comparison is undertaken in respect of the interpretation of mechanism and predic-tive ability for these two categories of QSAR approaches and highly predictive QSAR models have been developed.

关键词： nitroaromatics, mutagenicity, mechanism, 3D-QSAR, CoMFA.

Genesis of ^(230)Th excess in basalts from mid-ocean ridges and ocean islands:Constraints from the global U-series isotope database and major and rare earth element geochemistry

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Science china Earth Sciences 2010年第10期53卷 1486-1494页

作者： ZHANG GuoLiang1,2 & ZENG ZhiGang1 1 Key laboratory of marine Geology and environment,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,china 2 Graduate university of Chinese Academy of Sciences,Beijing 100049,china 1. Key laboratory of marine Geology and environment Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Based on 230Th-238U disequilibrium and major element data from mid-ocean ridge basalts(MORBs) and ocean island basalts(OIBs),this study calculates mantle melting parameters,and thereby investigates the origin of 230Th excess.(230Th/238U) in global MORBs shows a positive correlation with Fe8,Po,Na8,and Fmelt(Fe8 and Na8 are FeO and Na2O contents respectively after correction for crustal fractionation relative to MgO = 8 wt%,Po=pressure of initial melting and Fmelt=degree of melt),while 230Th excess in OIBs has no obvious correlation with either initial mantle melting depth or the average degree of mantle ***,compared with the MORBs,higher(230Th/238U) in OIBs actually corresponds to a lower melting *** suggests that the 230Th excess in MORBs is controlled by mantle melting conditions,while the 230Th excess in OIBs is more likely related to the deep garnet *** vast majority of calculated initial melting pressures of MORBs with excess 230Th are between 1.0 and 2.5 GPa,which is consistent with the conclusion from experiments in recent years that DU>DTh for Al-clinopyroxene at pressures of >1.0 *** initial melting pressure of OIBs is 2.2-3.5 GPa(around the spinel-garnet transition zone),with their low excess 226Ra compared to MORBs also suggesting a deeper mantle ***,excess 230Th in MORBs and OIBs may be formed respectively in the spinel and garnet stability *** addition,there is no obvious correlation of K2O/TiO2 with(230Th/238U) and initial melting pressure(Po) of MORBs,so it is proposed that the melting depth producing excess 230Th does not tap the spinel-garnet transition *** and MORBs in both(230Th/238U) vs.K2O/TiO2 and(230Th/238U) *** plots fall in two distinct areas,indicating that the mineral phases which dominate their excess 230Th are ***/Yb-Ce curves of fast and slow ridge MORBs are similar,while,in comparison,the Ce/Yb-Ce curve for OIBs shows more influence from *** mechanism

关键词： excess 230Th clinopyroxene garnet spinel-lherzolite mid-ocean ridge ocean island

Spatial variations of tidal water level and their impact on the exposure patterns of tidal land on the central Jiangsu coast

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Acta Oceanologica Sinica 2010年第1期29卷 79-87页

作者： WANG Zhenyan GAO Shu HUANG Haijun Key laboratory of marine Geology and environment Chinese Academy of Sciences Qingdao 266071 China Graduate School Chinese Academy of Sciences Beijing 100039 China MOE Key laboratory for Coast and Island Development Nanjing University Nanjing 210093China

The exposed area of intertidal zone varies with tidal water level changes, If intercomparisons of satellite images are adopted as a method to determine geomorphological changes of the intertidal zone in response to accretion or erosion processes, then the effect of water level variations must be evaluated. In this study, two Landsat TM images overpassing the central Jiangsu coastal waters on 2 January and 7 March 2002, respectively, were treated by the changing detection analysis using Image Differencing and Post-classification Comparison. The simultaneous tide level data from four tide gauge stations along the coast were used for displaying the spatial variations of water levels and determining the elevations of waterlines. The results show that the spatial variations of water levels are highly significant in the central Jiangsu coastal waters. The huge differences of tidal land exposure patterns between the two imaging times are related mainly to the spatial variations of tidal water levels, which are controlled by the differences in tidal phases for different imaging times and the spatial variations of water level over the study area at each imaging time. Under complex tidal conditions, e.g., those of the central Jiangsu coastal waters, the tide-surge model should be used to eliminate effectively the effects of water level variations on remote sensing interpretation of geomorphological changes in the intertidal zone.

关键词： waterline water level variations exposure patterns central Jiangsu coast remote sensing

Enrichment mechanisms of rare earth elements in marine hydrogenic ferromanganese crusts

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Science china Earth Sciences 2011年第2期54卷 197-203页

作者： JIANG XueJun1,2,LIN XueHui1,2,YAO De3,4 & GUO WeiDong5 1 Key laboratory of marine Oil and Gas Resources and marine environment,Ministry of Land and Resources,Qingdao 266071,china 2 Qingdao Institute of marine Geology,china Geological Survey,Qingdao 266071,china 3 Institute of Resources and environment,Shandong university of Technology,Zibo 255049,china 4 Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,china 5 Department of Oceanography,Xiamen university,Xiamen 361005,china 1. Key laboratory of marine Oil and Gas Resources and marine environment Ministry of Land and Resources Qingdao 266071 China2. Qingdao Institute of Marine Geology China Geological Survey Qingdao 266071 China3. Institute of Resources and Environment Shandong University of Technology Zibo 255049 China4. Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China5. Department of Oceanography Xiamen University Xiamen 361005 China

A series of selective extraction experiments were conducted on marine hydrogenic ferromanganese crusts from the seamount near the Line Island to investigate the distribution of rare earth elements （REEs） and the mechanisms of combination between REEs and the hydrogenic ferromanganese crusts. The enrichment of REEs in hydrogenic ferromanganese crusts is attributed mainly to the mineral or oxide/hydroxide of the crust rather than the growth environment. The REEs are present mainly in amorphous ferric oxide/hydroxide rather than in 6-MnO2. Amorphous ferric oxide/hydroxide preferentially combines free REE3＋, while 6-MnO2 combines the REE-carbonate complexes in modern seawater. The REEs in seawater are combined more strongly with amorphous ferric oxide/hydroxides than with 6-MnO2. The positive Ce anomaly in hydrogenic ferromanganese crusts results from the oxidation of soluble Ce3＋ to insoluble Ce4＋ by the actively soluble oxygen of the bottom current rather than by the oxidation of δ-MnO2.

关键词： rare earth elements hydrogenic ferromanganese crust selective extraction experiment geochemistry combinationmechanism

The Depositional environment of the Cretaceous Kizilsu Group in Xinjiang——With a Discussion of the Lowermost marine Horizon of the Cretaceous in the Western Tarim Basin

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Acta Geologica Sinica(English Edition) 1991年第4期65卷 441-453页

作者： Guo Xianpu china university of Geosciences, Beijing Sun Sheping china university of Geosciences Beijing

In this paper. it is demonstrated that there exist marine horizons in the upper part of the lower subcycleand the upper subeycle of the Kizilsu Group in Xinjiang. based on new evidence of authigenic glauconite.boron content. carbon and oxygen stablc isotopic analyses. and lithological and sedimentary features. The up-per part of the lower subeycle is the lowermost marine horizon of the Cretaceous in the western Tarim Basin,which is inferred to be of Barremian age.

关键词： In With a Discussion of the Lowermost marine Horizon of the Cretaceous in the Western Tarim Basin The Depositional environment of the Cretaceous Kizilsu Group in Xinjiang

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

Infragravity waves with internal wave characteristics in the south of the Bohai Sea of china

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Acta Oceanologica Sinica 2003年第2期22卷 171-178页

作者： Fan Zhisong, Gao Guoping, Yin Xunqiang, Fan Yu, Wu Wei marine environment College,Ocean university of china,Qingdao 266003, china Ocean Univ china Marine Environm Coll Qingdao 266003 Peoples R China

The measurements by using ADCP (500 KH) and CTD were made during August 2000in the south (37?5'N, 120?5'E) of the Bohai Sea, where the water depth was about 16.5 m. The data of horizontal velocity with sampling interval of 2 min in 7 layers were obtained. The power spectrum analysis of these data indicates that there are very energetic infragravity waves with a period of about 6 min. The coherence spectrum analysis and the analysis of temporal variation of shear show that these infragravity waves are mainly the free wave model (properties of edge waves), in the meantime they possess some characteristics of internal waves, which are likely due to the distinctive marine environment in this area. It is speculated on that the instability processes (chiefly shear instability) of sheared stratified tidal flow owing to the effect of sea-floor slope in the coastal area might be the main mechanism generating these infragravity waves.

关键词： Infragravity waves edge waves internal waves vertical shear of horizontal velocity internal mixing

基于脂质生物标志物评估河道型水库表层沉积物有机质来源

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湖泊科学 2024年第1期36卷 137-148,I0001页

作者：宿苧仁 Emilie Jardé 尹月鹏 marine Liotaud 张雯成都理工大学生态环境学院国家环境保护水土污染协同控制与联合修复重点实验室地质灾害防治与地质环境保护国家重点实验室成都610059 法国国家科学研究中心(雷恩第一大学) 雷恩35000

水电开发导致河岸生境破碎化程度加剧和水库沉积物截留问题日益突出,而目前关于河道型水库有机质(OM)溯源及分布特征的研究较少,进而造成OM在水库复杂环境介质中迁移机理尚不清楚。本研究将脂质生物标志物分析方法应用于大渡河瀑布沟水... 详细信息

水电开发导致河岸生境破碎化程度加剧和水库沉积物截留问题日益突出,而目前关于河道型水库有机质(OM)溯源及分布特征的研究较少,进而造成OM在水库复杂环境介质中迁移机理尚不清楚。本研究将脂质生物标志物分析方法应用于大渡河瀑布沟水库表层沉积物,经过气相色谱-质谱法对沉积物OM脂质组分进行了分析,将其量化并分为自然、成岩、热源和污水标志物4种来源。结果表明:OM平均含量坝前(10.7%±4.8%)>坝后(7.3%±0.9%)>库中(6.7%±1.8%),说明水库对沉积物OM的截留有显著影响。可提取脂质组分主要来源于自然标志物(45.9%±13.9%),碳偏好指数、陆源/水生比和陆生与水生植物输入比显示OM主要来源于陆生高等植物,占自然定量分子的70.5%±9.1%。此外,坝前汉源城镇下游D6和D7点位人为标志物(44.6%±25.1%)分子明显比自然标志物(24.2%±3.7%)含量高,并进一步通过比例研究强调了污水标志物的贡献率较为突出(31.6%±12.8%),这与该地住宅区生活污水处理设施覆盖率较低相关,表明OM污染源组成变化与水库滞留效应的耦合作用有关。

关键词：有机质水库脂质生物标志物来源分布特征

Origin of a native sulfur chimney in the Kueishantao hydrothermal field, offshore northeast Taiwan

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Science china Earth Sciences 2007年第11期50卷 1746-1753页

作者： ZENG ZhiGang1, LIU ChangHua1,2, CHEN ChenTung A3, YIN XueBo1, CHEN DaiGeng1,2, WANG XiaoYuan1,2, WANG XiaoMei1,2 & ZHANG GuoLiang1,2 1 Seafloor Hydrothermal Activity laboratory of the Key laboratory of marine Geology and environment, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, china 2 Graduate university of Chinese Academy of Sciences, Beijing 100049, china 3 Institute of marine Geology and Chemistry, National Sun Yat-Sen university, Kaohsiung 804, Taiwan, china 1. Seafloor Hydrothermal Activity laboratory of the Key laboratory of marine Geology and environment Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. Graduate university of Chinese Academy of Sciences Beijing 100049 China 3. Institute of marine Geology and Chemistry National Sun Yat-Sen University Kaohsiung 804 Taiwan China

Analyses of rare earth and trace element concentrations of native sulfur samples from the Kueishantao hydrothermal field were performed at the Seafloor Hydrothermal Activity laboratory of the Key Labo-ratory of marine Geology and environment, Institute of Oceanology, Chinese Academy of Sciences. Using an Elan DRC II ICP-MS, and combining the sulfur isotopic compositions of native sulfur samples, we studied the sources and formation of a native sulfur chimney. The results show, when comparing them with native sulfur from crater lakes and other volcanic areas, that the native sulfur content of this chimney is very high (99.96%), the rare earth element (REE) and trace element constituents of the chimney are very low (ΣREEenvironment is favorable for formation of this native sulfur chimney in the Kueishantao hydrothermal field.

关键词： origin,native sulfur chimney,Kueishantao hydrothermal field,northeast Taiwan