書誌事項
- タイトル別名
-
- Preparation of trace amount of atmospheric methane for measuring <sup>14</sup>C isotopic ratio
- 大気中メタンの14C同位体比測定のための試料調製
- タイキチュウ メタン ノ 14C ドウイタイヒ ソクテイ ノ タメ ノ シリョ
この論文をさがす
説明
Carbon-14 isotopic measurements of atmospheric methane (CH4) provide useful information on its sources and behavior. We have assembled a preparation line to concentrate and purify low levels (〜2 ppmv) of methane for the measurement of 14C content with accelerator mass spectrometry (AMS). In this system, trace amounts of methane in nearly 1 m3 of air sample are cryogenically adsorbed on active carbon, purified by gas chromatography, combusted and collected as carbon dioxide. The mean yield of this procedure is 88.6±5.8 (1σ) %. Carbon dioxide, obtained from the above procedure, is divided into two parts : one portion is converted to graphite for AMS, and the other is used for δ13C measurement. Sample contamination is negligible compared with the precision of 〜1 pM (1σ) for AMS. The effect of isotopic fractionation in this procedure is also smaller than any of the source of contamination. The overall error of this procedure is lower than 1 ‰ for the δ13C measurement. From isotopic measurements of atmospheric methane in Nagoya City at the beginning of 1994, we found a high methane concentration air sample in which 14C content of methane was lower. This implies the contribution of fossil methane to the urban atmosphere.
収録刊行物
-
- 地球化学
-
地球化学 29 (2), 99-111, 1995
一般社団法人日本地球化学会
- Tweet
キーワード
詳細情報 詳細情報について
-
- CRID
- 1390282680719821696
-
- NII論文ID
- 110008679904
-
- NII書誌ID
- AN00141280
-
- ISSN
- 21885923
- 03864073
-
- NDL書誌ID
- 3916119
-
- 本文言語コード
- ja
-
- データソース種別
-
- JaLC
- NDL
- CiNii Articles
-
- 抄録ライセンスフラグ
- 使用不可
