摘要
稳定性同位素示踪技术,特别是碳、氮稳定性同位素已广泛地应用于农业化学、地球化学和环境化学。碳、氮同位素比值的质谱检测结果直接关系到示踪试验的可靠性。在目前缺乏富集碳、氮同位素的标准物质的条件下,通过实验室间的比对可以验证各实验室对碳、氮同位素比值检测能力、检测结果的准确性和可比性。我所在2013年组织和实施了一次由全国14个单位的检测实验室共17台仪器参加的农业、生态和环境样品中碳氮百分含量及其稳定性同位素比值的实验室间比对。我所制备了多种被检测的样品,有含碳氮的化学肥料、土壤和植物样品;在稳定性同位素富集度上,有自然丰度的和不同富集程度的同位素样品。除固体样品外,还有3种不同丰度的N2O和CO2气体样品。在进行检测结果的统计和评价时,采用Z比分衡量各实验室检测结果的可信度。本文汇总了2013年实验室间比对的结果。
Stable isotope tracer techniques, especially the use of carbon and nitrogen stable isotopes have been ex- tensively applied in agricuhural chemistry, geochemistry, and environmental chemistry. Calibration of mass spectrometers for precision in analysis of carbon and nitrogen isotope ratios are directly related to the reliability of the tracer experiments. Currently, as reference materials enriched in carbon and nitrogen stable isotopes are not readily available for calibration, it is advisable to verify accuracy of the instruments and comparability of their analyses through comparison between laborato- ries in carbon and nitrogen isotope ratio detection capability. For that, in 2013, a total of 14 testing laboratories and a to- tal of 17 sets of equipment all over the country were invited to participate in the comparison sponsored by the Institute of Soil Science, Chinese Academy of Sciences. Agricultural, ecological and environmental samples were used in the test for comparison. The institute also prepared a variety of test samples, including carbon and nitrogen-containing chemical fertil- izers, soils and plant samples. For analysis of stable isotopes, samples natural in isotope abundance and different in iso- tope enrichment level were also prepared. Besides solid samples, there were 3 kinds of N20 and CO2 gas samples different in isotope abundance for analysis. The Z score method was used to measure reliability of the analysis in each laboratory. In this paper, comparisons between the 14 laboratories were summarized in 2013.
出处
《土壤学报》
CAS
CSCD
北大核心
2015年第1期212-219,共8页
Acta Pedologica Sinica
