【作者】 甘义群； 周爱国； 刘存富；

【Author】 GAN Yiqun ZHOU Aiguo LIU Cunfu School of Environment Studies,China University of Geosciences,Wuhan,Hubei,430074

【机构】 中国地质大学环境学院；

【摘要】 目前的发现指出,硫酸盐的δ¹⁷O 和δ¹⁸6O 值,特别是△¹⁷O 值(=δ¹⁷O-0.52δ¹⁸O)能够提供关于大气圈中和地表环境中硫酸盐的起源、混合和迁移的独特的信息,仅仅使用δ¹⁸O 的测量结果不能圆满地解决相关问题。现有的分析硫酸盐的δ¹⁷O和δ¹⁸O 的方法极其辛苦,而且要求高纯的BrF₅。文中报道了从重晶石（BaSO₄）中直接产生O₂供同位素比值质谱计（IRMS）同时分析δ¹⁷O 和δ¹⁸O 的新方法。该方法使用了CO₂-激光氟化系统,该系统也可用于从硅酸盐和氧化物中定量的产生O₂。对于样品大于4 mg 来说,可以获得部分的但是一致的来自BaSO₄的氧的产量。每个工作日用该系统可以处理12个以上的样品。△¹⁷O 的分析误差为±0.05700,δ¹⁸O 的分析误差为±018‰。该方法可有效和准确地研究硫酸盐的△¹⁷O 值。更多还原

【Abstract】 Recent findings indicate that δ ¹⁷O and δ ¹⁸O values of sulfates,especially the △¹⁷O value(=δ ¹⁷O-0.52δ ¹⁸O),can pro-vide independent information for tackling such problems as the origin,mixing and transformation of sulfates in the atmospheric andsurface environments,which cannot be solved only by δ ¹⁸O measurements.The methods available for analyzing δ ¹⁷O and δ ¹⁸O of sul-fates are extremely laborious and demand high-purity BrF₅.Here the authors present a new method which generates O₂ directly frombarite（BaSO₄）for simultaneous analysis of δ ¹⁷O and δ ¹⁸O by isotope ratio mass spectrometry（IRMS）.The method utilizes a CO₂-Laser Fluorination system that can also be used to quantitatively generate O₂ from silicates and oxides.Partial but consistent oxygenyields from BaSO₄ are obtained for samples of>mg.The system may treat more than a dozen samples per working day,with theanalytical error being±0.05‰ and±0.87‰for δ ¹⁷O and δ ¹⁸O,respectively.With this new method,we can effectively and accu-rately study △¹⁷O values of sulfates.更多还原