AMS radiocarbon measurements of individual organic molecules : making preparative capillary GC system and its application to geochemical samples

单个有机分子的 AMS 放射性碳测量：制备型毛细管气相色谱系统及其在地球化学样品中的应用

• 批准号: 10354009
• 负责人: KAWAMURA Kimitaka
• 金额: $ 17.83万
• 依托单位: HOKKAIDO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10354009/
• 关键词: Radiocarbon; AMS; Chronology; Organic carbon age; Biomakers; Preparative GC; Aerosols; Geochemical samaples; 加速器質量分析計; 地球科学試料; 堆積物

Compound-specific radiocarbon analysis of individual fatty acids was conducted for a semi-urban aerosol sample using a preparative capillary gas chromatography (PCGC) system and an accelerator mass spectrometry (AMS). The aerosol fatty acids (C16 to C34) showed a typical bimodal distribution with two maxima at C16 and C26. Their carbon isotopic compositions ranged from -30.3 ‰ (C26) to -23.3 ‰ (C18), suggesting that they are derived from terrestrial higher plants and marine sources. Radiocarbon measurements of C16-C22 fatty acids showed modern 14C ages, suggesting that the acids are emitted from living higher plants and possibly from marineorganisms. On the other hand, C24-C26 fatty acids that arecharacteristic to terrestrial plant waxes showed 14C ages of 5860 (EA200) years. This suggests that some portion of higher molecular weight fatty acids have been stored in geocnemical reservoirs such as soils at least for hundreds to thousands of years arid then emitted to the atmosphere. These aged fatty acids could be in part transported long distances from the Asian continent through the atmosphere.

使用制备型毛细管气相色谱 (PCGC) 系统和加速器质谱 (AMS) 对城郊气溶胶样品中的各个脂肪酸进行了化合物特异性放射性碳分析。气溶胶脂肪酸（C16 至 C34）显示出典型的双峰。它们的碳同位素组成在-30.3 ‰ (C26) 到C16 和C26 处有两个最大值。 -23.3 ‰ (C18)，表明它们来自陆地高等植物和海洋来源。C16-C22 脂肪酸的放射性碳测量显示现代 14C 年龄，表明这些酸是从活的高等植物中释放出来的，也可能是从海洋生物中释放出来的。另一方面，陆地植物蜡特有的C24-C26脂肪酸显示14C年龄为5860（EA200）这表明，某些较高分子量的脂肪酸已经在土壤等地质储库中储存了至少数百年至数千年，然后排放到大气中。穿过亚洲大陆的大气层。