Research on the origin of micrometeorite by extremely accurate instrumental neutron activation analysis
Grant-in-Aid for Scientific Research (C)
|Allocation Type||Single-year Grants|
|Research Institution||Rissho University(1998-1999)|
FUKUOKA Takaaki Rissho University, Geo-Environmental Science, Associate Professor, 地球環境科学部, 助教授 (90080473)
|Project Period (FY)
1997 – 1999
Completed(Fiscal Year 1999)
|Budget Amount *help
¥3,500,000 (Direct Cost : ¥3,500,000)
Fiscal Year 1999 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1998 : ¥400,000 (Direct Cost : ¥400,000)
Fiscal Year 1997 : ¥2,600,000 (Direct Cost : ¥2,600,000)
|Keywords||cosmic dust / instrumental neutron activation analysis (INAA) / unmelted micrometeorite / standard sample / the Dome Fuji station, Antarctica / Yamato bare ice field, Antarctica / lithophile elements / siderophile elements / 高純度ポリエチレンフィルム / ガラス質球粒 / やまと裸氷原 / 機器中性子放射化分析(INAA)法 / 南極ドームFuji / 微粒物質磁気選別装置 / 南極雪中 / 深海底堆積物|
The first purpose of this research is establishment of accurate analytical technique for multi-elements by instrumental neutron activation analysis (INAA) for multi-elements in ultra-small micrometeorite sample. The second is accumulate of chemical data for precise discussion of the origin of cosmic dust.
1. Development of the rapid handling method of instrumental neutron activation analysis for ultra-small micrometeorite sample. We cannot see tiny sample such diameter as less than 100 μm with the necked eye. By using the high purity polyethylene bag (3x3 mm) which enclosed tiny samples, a rapid handling system of INAA is established. New irradiation container of tiny sample for INAA using long half life nuclides was also developed.
2. Glass standards for lithophile elements such as rare earth elements were made from standard rock power (e.g. JB-1). An alloy standard for siderophile elements (Au, Ir etc) was made from high purity metals.
Homogeneities for 10 to 100 μg range of these standards were checked. However, radio activity of alloy standard was too high compared with the radio activities for micrometeorite samples.
3. Micrometeorite samples collected from sediments in the water tank for living at the Dome Fuji station, Antarctica were analyzed by INAA.
4. Preliminary analyses were performed to unmelted micrometeorite samples collected from Yamato bare ice field, Antarctica.
Research Products (15results)