生物有机酸的来源及其测试分析方法

对目前生物有机酸的来源及其测试分析方法研究现状进行了评述，目前已知的生物有机酸的来源有植物生代过程中的直接释放，有机物质的燃烧，机动车辆燃油的尾气排放、稀烃等不饱和有机物的大气氧化，人类生产和生活对大气环境的污染以及及甲酸蚁社会活动过程中的释放等等，有机酸来源的一个判别指标是甲酸／乙酸比值的大小，与人类活动有关的来源中，甲酸／乙酸比值〈１。而自然源的两者比值〉１。要准确地测定降水中生物有机酸的含量

Organic Acids: A Review for Their Sources and Measurements

Current studies on organic acid sources and determination methods are reviewed. The sources include emissions from vegetation, biomass burning, automobile exhaust. oxidation in the atmosphere of alkenes and other hydrocarbons. anthropogenic pollution as well as emission of formicine ants. The ratio of formic to acetic is employed to identify the sources of organic acids. The ratio is less than 1 for the organic acid sources relating to human activities. Whereas it will be larger than 1 for natural sources. Determination of organic acids has to face the hurdles from the acid's volatility. contamination susceptibility and trace concentration. Although the analyzing principles are common. analyzing methods are different for different samples that have different anionic components, owing to the difference in ion exchange columns, eluent solution and working conditions for separation of anions. The detection limit for organic acids depends not only on the instrument and analytical conditions. but also on the specific species and its concentration. The detection limits of formic and fluoride are lower than that of acetic and MSA. Similarly. analytical errors also dependent on instrument. analytical method. species to be determined and its concentration, as well as its detection limit. Corresponding to their detection limits. the analytic uncertainties for formic and fluoride are lower than that for acetic and MSA. At present the best method enables the analytical error lower than about 3% - 5 % for organic acids.