10 research outputs found

    用离散速度方法计算浅水长波方程

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    国家自然科学基金资助项目 (1970 2 0 0 5 )用离散速度法计算浅水波方程 ,将空气动力学方程和浅水波方程作了比较 ,用 Nadiga提出的近平衡流动方法模拟浅水波方程的连续和间断解。计算了一维的溃坝波问题和 Thacker提出的连续解问题 ,结果与精确解作了比较 ,并且计算了水流跃过障碍物的问

    Occurrence and Distribution of Organotin Compounds in Thais clavigera from Xiamen Coast

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    采用戊基化格式衍生法,gC-fPd分析了厦门港周边海域9个小岛屿分布的疣荔枝螺(THAIS ClAVIgErA)体内3种丁基锡化合物(buTylTInS)和3种苯基锡化合物(PHEnylTInS)的存在形态与分布特征.结果表明,丁基锡化合物总浓度(ΣbTS)为0.3~70.6ng.g-1,平均值为28.8ng.g-1,以一丁基锡化合物(MbT)为主.苯基锡化合物总浓度(ΣPHTS)为nd~18.8ng.g-1,平均值为7.9ng.g-1,以三苯基锡化合物为主.厦门港周边海域以丁基锡化合物为主要污染物,占到总有机锡化合物(ΣOTS)的74.3%~96.8%.疣荔枝螺体内(ΣbTS)和(ΣPHTS)呈现从厦门港内到港外逐渐降低的趋势.疣荔枝螺体内TbT和TPHT的浓度显示良好的相关关系(r2=0.7109,P<0.01),说明TPHT和TbT来源趋同,即来源于船舶防污涂料,或水产养殖污染源.与我国东南沿海港口相比,厦门海域疣荔枝螺体内丁基锡化合物的污染处于一个较低水平但比2002年有所加重.Occurrence and distribution of 6 organotin compounds including butyltin and phenyltin species were detected in Thais clavigera which were collected from 9 coastal areas sites around Xiamen Coast,by pentylized derivatization,GC-FPD.Results indicated that all Thais clavigera samples were contaminated with organotin compounds.The concentrations in Thais clavigera soft bodies varied from 0.3 to 70.6 ng.g -1 with a mean value of 28.8 ng.g -1 for butyltin compounds,and from nd to 18.8 ng.g -1 with a mean value of 7.9 ng.g -1 for phenyltin compounds,respectively.MBT and TPhT were high levels in butyltin compounds and phentyltin compounds,respectively.In addition,butyltin compounds were the dominant contaminates in all samples with high percentage from 74.3% to 96.8%.There was a significant correlation between TBT and TPhT (R2 = 0.710 9,p < 0.01).This result showed that both TBT and TPhT came from antifouling paints for ships or for mariculture nets.Compared with those data reported from the other regions around southeast coast of China,present study reveals that contaminated level of organotin compounds in Thais clavigera are relatively lower in Xiamen Coast.But it is higher than those in 2002.国家自然科学基金项目(40476048;20777060

    Imposex of Thais clavigera and Cantharus cecillei in the coastal waters of Xiamen

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    海产腹足类性畸变以其对有机锡的敏感性、特异性和不可逆性而成为海洋有机锡污染的理想指示种。调查研究了厦门海域岩相海岸带疣荔枝螺(THAIS ClAVIgErA)和甲虫螺(CAnTHAruS CECIllEI)的性畸变情况,通过生物学指标IOI(性畸变率)、rPSI(相对阴茎发展指数)、VdSI(输精管发展指数)及SrI(性比指数)综合评价其性畸变发展程度,间接指示厦门周边海域的有机锡污染程度。研究结果发现,在采集疣荔枝螺的17个站点中有5个站点种群性畸变率为100%,其中宝珠屿种群性畸变程度最为严重,VdSI达4,采集甲虫螺的4个站点的种群性畸变率均为100%。性畸变程度较严重的种群普遍集中于厦门西港,并且表现出由港内到港外逐渐减轻的趋势,而白城、会展中心和大嶝岛等位于开阔的厦门东海域的种群性畸变程度最轻,与往年厦门西海域有机锡污染监测数据相比一致,体现出性畸变程度与有机锡污染程度及海港码头远近之间的相互关系。The degree of imposex,i.e.the imposition of male characteristics onto females,in neogastropods can be used as a sensitive and accurate biomarker to evaluate organotin contamination in coastal marine environment.Now,the imposex status in females of Thais clavigera and Cantharus cecillei in 17 sites was investigated to evaluate the organotin contamination along Xiamen Bay during 2006 and 2007.The four indices including incidence of imposex(IOI),relative penis size index(RPSI),vas deferens sequences index(VDSI) and sex ratio index(SRI) were used comprehensively to assess the imposex status in order to ascertain the extent of organotin bioavailability in Xiamen Bay.Based on this research,T.clavigera in 5 sites and C.cecillei in all survey sites exhibited the IOI of 100%.At Bao ZhuYu Islet,the imposex level was the most serious with maximum VDSI value of 4.In general,the imposex level decreased from the inner to the outer of Xiamen Western Harbour,and the populations in the open Xiamen Eastern Waters including Bai Cheng,Convention and Exhibiton Center and Dadeng Island showed a lower imposex level.These results were accordant with the concentrations of organotins in 2005.The imposex degree also increased with increasing organotin contamination and decreasing distance from shipping facilities.国家自然科学基金资助项目(40476048);厦门大学近海海洋环境科学国家重点实验室开放基金资助项目;厦门大学新世纪优秀人才计划基金资助项

    Euler方程的双分布函数格子Boltzmann Godunov方法

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    应用双分布函数系统,通过Godunov分解,构造了一维Euler方程的格子Boltzmann算法。解决了传统格子气固有的GC问题与能量方程之间的矛盾,实现了分布函数与宏观物理量之间的一一对应

    Urbanization spatial expansion and regional landscape ecological risk of Yantai City

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    采用遥感、GIS及数理统计方法,引入城市扩展强度指数研究了烟台市区1974—2009年城镇空间扩展时空变化特征,并利用景观指数和生态风险指数,研究了1990—2009年在城镇扩展下的烟台市区城镇景观格局动态变化和区域生态风险空间特征。结果表明:1974—2009年,烟台市区城镇用地面积增幅189.77 km~2,其中2004—2009年城镇用地扩展强度指数是1974—1990年的3.92倍。城镇和耕地分别是研究区土地利用面积变化最显著的两大类型,土地利用格局景观指数变化反映出该期间人类活动干扰强度逐渐加剧。研究区景观生态风险呈圈层状分布,靠近海岸线的区域生态风险较高,远离海岸线的内陆生态风险则较低。2009年高生态风险区和较高生态风险区比例是1990年的2.23倍,城镇扩展强度与区域生态风险之间呈现良好的线性关系

    烟台市城镇空间扩展及区域景观生态风险

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    采用遥感、GIS及数理统计方法,引入城市扩展强度指数研究了烟台市区1974—2009年城镇空间扩展时空变化特征,并利用景观指数和生态风险指数,研究了1990—2009年在城镇扩展下的烟台市区城镇景观格局动态变化和区域生态风险空间特征。结果表明:1974—2009年,烟台市区城镇用地面积增幅189.77 km~2,其中2004—2009年城镇用地扩展强度指数是1974—1990年的3.92倍。城镇和耕地分别是研究区土地利用面积变化最显著的两大类型,土地利用格局景观指数变化反映出该期间人类活动干扰强度逐渐加剧。研究区景观生态风险呈圈层状分布,靠近海岸线的区域生态风险较高,远离海岸线的内陆生态风险则较低。2009年高生态风险区和较高生态风险区比例是1990年的2.23倍,城镇扩展强度与区域生态风险之间呈现良好的线性关系

    Imposex ofTha is clavigera and Can tharus cecillei in the coa sta lwa ters ofX iam en

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    [摘要]:海产腹足类性畸变以其对有机锡的敏感性、特异性和不可逆性而成为海洋有机锡污染的理想指示种。调查研究了厦门海 域岩相海岸带疣荔枝螺(Tha is clavigera ) 和甲虫螺(Cantha rus cecillei) 的性畸变情况, 通过生物学指标IO I( 性畸变率)、RPSI( 相 对阴茎发展指数)、VDSI(输精管发展指数)及SRI(性比指数) 综合评价其性畸变发展程度, 间接指示厦门周边海域的有机锡污 染程度。研究结果发现, 在采集疣荔枝螺的17个站点中有5个站点种群性畸变率为100%, 其中宝珠屿种群性畸变程度最为严 重, VDSI达4, 采集甲虫螺的4个站点的种群性畸变率均为100%。性畸变程度较严重的种群普遍集中于厦门西港, 并且表现 出由港内到港外逐渐减轻的趋势, 而白城、会展中心和大嶝岛等位于开阔的厦门东海域的种群性畸变程度最轻, 与往年厦门西 海域有机锡污染监测数据相比一致, 体现出性畸变程度与有机锡污染程度及海港码头远近之间的相互关系。[Abstract]:The degree of mi posex, .i e. the mi position ofmale characterist ics onto females, in neogastropods can be used as a sensit ive and accurate biomarker to evaluate organotin contam inat ion in coastalmarine environment. Now, the mi posex status in females ofTha is clavigera andCantharus cecillei in 17 s ites was investigated to evaluate the organotin contam ination along Xiamen Bay during 2006 and 2007. The four indices including inc idence of mi posex( IO I), relative pen is size index (RPSI), vas deferens sequences index(VDSI) and sex ratio index( SRI) were used comprehens ively to assess the mi posex status in order to ascertain the extent of organotin bioavailab ility in Xiamen Bay. Based on this research, T. clavigera in 5 s ites and C. cecillei in all survey sites exhib ited the IOI of 100%. A t Bao ZhuYu Islet, the mi posex level was the most serious with maxmi um VDSI value of 4. In genera,l the mi posex level decreased from the inner to the outer ofX iamen Western H arbour, and the populations in the open X iamen EasternWaters including Ba iCheng, Convention and Exhib iton Center and Dadeng Is land showed a lower mi posex leve.l These results were accordantwith the concentrations of organotins in 2005. The mi posex degree also increased with increas ing organot in contam inat ion and decreasing distance from shipping facilities.国家自然科学基金资助项目( 40476048); 厦门大学近海海洋环境科学国家重点实验室开放基金资助项目; 厦门大学新世纪优秀人才 计划基金资助项

    1995~2011年CERN土壤环境元素含量数据集

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    土壤环境是地球环境的重要组成部分。目前土壤环境问题的关注重点在于土壤污染。我国土壤污染以无机污染为主。中国生态系统研究网络(Chinese Ecosystem Research Network,CERN)自1988年组建以来,在中国主要农田、森林、草原、荒漠、湿地生态系统中,按统一的规范,对与土壤环境状况有关的铁、锰、铜、锌、硼、钼、镉、铬、铅、镍、汞、砷、硒元素进行了长期定位监测。通过对CERN典型生态样地表层土壤环境元素监测数据进行加工处理,获得1995~2011年中国陆地生态系统土壤环境元素含量数据集。本数据集中13种土壤环境元素指标测定的相对误差平均为6.55%,重复测定的相对偏差为7.70%。同时附有完整的背景信息,保证了数据在空间和时间上的一致性。本数据集可以为全国和区域土壤环境质量评估、土壤污染风险评价以及环境土壤学研究等工作提供数据基础
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