Geochemical cycles of platinum group elements at the earth surface -Role of anthropogenic and cosmic sources-

地球表面铂族元素的地球化学循环-人为和宇宙源的作用-

基本信息

批准号：
15540466
负责人：
AMAKAWA Hiroshi
金额：
$ 2.05万
依托单位：
The University of Tokyo (2004-2005)Tokyo Metropolitan University (2003)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2005
项目状态：
已结题

项目摘要

My research results are summarized as follows.1. Development of high precision and sensitivity method for determining abundances of platinum group elements in solid samples.I have developed high precision and sensitivity method for determining abundances of platinum group elements (PGE : Ru, Rh, Pd, Os, Ir and Pt) in solid samples by isotope dilution method (for Ru, Pd, Os, Ir and Pt) and external calibration method (only for Rh) using ICP-MS combined with a fire assay preconcentration technique. We applied this method to a standard rock JP-1 issued from the Geological survey of Japan (GSJ). The errors of PGE range 13-25%(2s ; n=5), which are comparable with those by the similar methods combined with chemical separation of PGE. Compared our data with the preferable data proposed by GSJ, the large deviations are observed for Ir. Various evidences indicate that our data are much more reliable than the preferable value.2. Educidation of horizontal transport processes of elements in ocean using the Nd isotopic compositions of seawatersTo elucidate the horizontal transport processes of elements in ocean, I determined the vertical distribution of Nd isotopic compositions at four stations in the Northwest Pacific together with that of surface seawaters at the Northwest Pacific. These results suggest that Nd is involved in the active horizontal transport processes in the surface ocean (above 100-250m).3. Development of high sensitivity method for determining abundances of scandium (Sc) in seawater and its application to marine chemistryTo test Sc as a possible indicator of continentally derived material to the ocean, we developed of high sensitivity method for determining abundances of Sc in seawater. The vertical profile at the station near the Hawaii Islands showed so called "nutrient type" one, which was similar with Y and lanthanides.

我的研究结果总结如下1。开发高精度和灵敏度方法，以确定固体样品中铂群元素的丰度。I已开发出高精度和灵敏度方法，用于确定铂类元素的丰度（PGE：RU，RH，RH，RH，PD，PD，OS，IR和PT）通过同位素稀释方法（用于RU，PD，OS，IR和PT）和外部校准方法（仅用于RH）的样品，并使用ICP-MS与火灾测定预浓缩技术结合使用。我们将此方法应用于日本地质调查局（GSJ）发行的标准岩石JP-1。 PGE的误差范围为13-25％（2s; n = 5），与类似方法与PGE的化学分离相当。将我们的数据与GSJ提出的优选数据进行了比较，对于IR，观察到了较大的偏差。各种证据表明，我们的数据比可取的值更可靠。2。使用Seawatersto的ND同位素组成对海洋中元素的水平运输过程进行教育，阐明了海洋中元素的水平运输过程，我确定了西北太平洋地区四个位置的ND同位素组成的垂直分布以及西北太平洋的四个站点以及在地表海上的垂直分布西北太平洋。这些结果表明，ND参与了地表海洋中的主动水平运输过程（超过100-250m）。3。开发高灵敏度方法来确定海水中的sc（SC）及其在海洋化学测试SC中的应用，这可能是向海洋衍生材料的指标，我们开发了高灵敏度方法，用于确定海水中SC的丰富性。夏威夷群岛附近车站的垂直轮廓显示出所谓的“营养型”，与Y和Lanthanides相似。