中文摘要：

目前的发现指出，硫酸盐的δ^17O和δ^18O值，特别是△^17O值（=δ^17O-0．52δ^18O）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δ^18O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δ^17O和δ^18O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δ^17O和δ^18O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4mg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±0．05％，δ^18O的分析误差为±0．8‰。该方法可有效和准确地研究硫酸盐的△^17O值。

英文摘要：

Recent findings indicate that δ^17O and δ^18O values of sulfates, especially the △^17O value （ = δ^17O- 0. 52δ^18O）, can provide independent information for tackling such problems as the origin, mixing and transformation of sulfates in the atmospheric and surface environments, which cannot be solved only by δ^18O measurements. The methods available for analyzing δ^17O and δ18^O of sulfates are extremely laborious and demand high-purity BrF5. Here the authors present a new method which generates O2 directly from barite （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 oxygen yields from BaSO4 are obtained for samples of 〉4 rag. The system may treat more than a dozen samples per working day, with the analytical error being ± 0.05‰ and ± 0.8‰ for δ^17O and δ^18O, respectively. With this new method, we can effectively and accurately study △^17O values of sulfates.