日中共通国語科教材の教材化と指導法に関する研究

早大学位記番号:新7053早稲田大

Distribution Features and Speciation of Heavy Metals in Surface Sediments of Main Mangrove of China

利用ICP-MS分析了我国红树林主要分布区表层沉积物的As含量和形态,阐明As的分布及其形态特征.结果表明,表层沉积物中w(As)为3.14～19.16mg/g,平均值为8.14mg/g.表层沉积物中w(As)与w(Fe),w(Mn),pH,w(有机质),粉粒和黏粒所占比例呈显著或极显著正相关.表层沉积物中的As主要以残渣态存在,其次为有机质-硫化物结合态.在整个研究区域,As的5种形态在总量中的所占比例:可交换离子态为14.40%,碳酸盐结合态为1.41%,铁锰氧化物结合态为2.16%,有机质-硫化物结合态为30.40%,残渣态为50.65%.可交换离子态所占比例与w(有机质)和pH呈极显著正相关.有机质-硫化物结合态所占比例与盐度、黏粒和粉粒所占比例呈显著或极显著正相关.残渣态所占比例与盐度、粉粒和黏粒所占比例呈极显著正相关.Arsenic contents in surface sediments collected from mangrove were analyzed with a PE DRC-e ICP-MS,and the distribution and species of As were identified.The results showed that As content ranged from 3.14～19.16 mg/g,with an average content of 8.14 mg/g.As content correlated well and positively with the contents of Fe and Mn,pH,organic content,silt and clay.Residual As was the primary species,and organic and sulfide As were the secondary species in the surface sediments.Among five As species,the exchangeable As accounted for 14.40%,carbonate As accounted for 1.41%,Fe-Mn oxides As accounted for 2.16%,organic-sulphide As accounted for 30.40%,and residual As accounted for 50.65%.Exchangeable As positively correlated with organic content and pH significantly.Organic-sulfide As and residual As positively correlated with salinity,silt and clay significantly.国家自然科学基金项目(40676064,30530150

对称域基本解函数的构造及应用

在对称区域中,构造出满足对称边界条件的基本解函数,并推广到基本解方法(MFS)中求解Poisson方程的边界值问题.利用构造出的基本解,输入数据和所需求解的线性方程组数目可减少到原来(不利用对称性的基本解函数所需的方程组数目)的1/2或1/4,具有计算时间短、精度高、编程简单、输入数据少等优点.通过数值计算可以看出,计算结果与解析解之间的误差很小,说明该方法值得推广使用

Distribution of Mercury in Surficial Sediments from Main Mangrove Wetlans of China

作者简介: 丁振华(1966~ ) , 男, 博士, 教授, 主要研究方向为污染生 态学, E-mail : dzh@ xmu. edu. cn[中文文摘]通过对我国主要红树林区表层沉积物中总汞含量和环境因素的测定,研究了红树林湿地沉积物中汞的分布规律和影响因子之间的关系.结果表明,我国红树林湿地沉积物中总汞的含量范围是2.3~903.6 ng.g-1,平均值为(197±137.6)ng.g-1,福建洛阳桥[(467.5±68.8)ng.g-1]、浮宫[(438.2±147.0)ng.g-1]、鹅湾[(264.3±89.2)ng.g-1]、姚家屿[(125.4±27.1)ng.g-1],海南三亚[(164.8±143.9)ng.g-1]、东寨港[(314.1±335.7)ng.g-1],广东深圳[(179.9±7.7)ng.g-1]等7个红树林区的汞含量均显著高于当地土壤背景值,汞污染严重;而福建云霄[(63.3±43.9)ng.g-1]、广东高桥[(178.6±127.0)ng.g-1]、广西大冠沙[(26.1±18.8)ng.g-1]、山口[(73.8±21.1)ng.g-1]、北仑河口[(117.8±51.4)ng.g-1]、钦州湾[(147.5±107.6)ng.g-1]等红树林区汞含量接近于背景值,基本无污染.红树林湿地中汞含量的差异是众多环境因素和人类活动相互交叉影响的结果.红树林湿地中,pH值、粒度、有机质、Fe/Hg、Mn/Hg与总汞含量显著相关.其中,黏粒和Fe/Hg是影响沉积物中汞含量最显著的因素.环境因素对总汞含量的综合影响作用,可以用线性回归方程表示.[英文文摘]Surficial sediment samples were collected from main mangrove wetlands of China, mercury, pH, salinity, organic matters, grain size, Fe/Hg , Mn/Hg were analyzed. Mercury content ranges from 2.3 to 903.6 ng.g- 1, with a average of ( 197±137.6) ng.g- 1. Compared with local background level, serious Hg pollution with high Hg content was found in 7 areas, including Luoyangqiao [ ( 467.5 ±68.8)ng.g- 1] , Fugong [ ( 438.2 ± 147. 0) ng.g- 1 ] , Ewan [ ( 264.3 ± 89.2) ng.g- 1 ] , Yaojiayu [ ( 125.4 ± 27.1) ng.g- 1 ] , Fujian Province;Sanya [ ( 164. 8 ±143.9) ng.g- 1 ] , Dongzhaigang [ ( 314.1 ±335. 7) ng.g- 1 ] , Hainan Province, Shenzhen [ ( 179.9 ±7. 7) ng.g- 1 ] ,Guangdong Province. Hg content was similar with background value in the other 6 areas, including Yunxiao [ ( 63.3 ±43.9) ng.g- 1 ] , Fujian Province; Gaoqiao [ ( 178. 6 ± 127.0) ng.g- 1 ] , Guangdong Province; Daguansha [ ( 26.1 ±18.8) ng.g- 1 ] , Shankou [ ( 73.8±21.1)ng.g- 1 ] , Beilun estuary [ ( 117.8 ±51. 4) ng.g- 1 ] , Qinzhou Bay [ ( 147.5 ±107. 6) ng.g- 1] , Guangxi Autonomous Region. Discrepancy of total Hg concentrations in mangrove wetlands is due to many environmental factors and human activities. Parameters such as grain size, pH,organic matter, Fe/Hg, Mn/Hg are significantly correlated with total Hg respectively. Clay and Fe/Hg are obvious factors influencing total Hg concentration. Impact of environmental factors on mercury can be showed by regression equation.国家自然科学基金项目(40676064,30530150);厦门大学创新团队项