Kim Ki-Hyun, Ju Do-Weon, Joo Sang-Woo
Atmospheric Environment Laboratory, Department of Earth and Environmental Sciences, Sejong University, Seoul, South Korea.
Talanta. 2005 Oct 31;67(5):955-9. doi: 10.1016/j.talanta.2005.04.048.
In this work, the recovery rate (RR) of preconcentration technique was examined using a combination of the Peltier cooling (PC) and thermal desorption (TD) system for the gas chromatographic (GC) analysis of reduced sulfur compounds (RSC) in air. The possible loss or gain of analytes resulting from the use of the PC/TD system was estimated by analyzing equimolar standards (10ppm) of four S compounds including H(2)S, CH(3)SH, DMS, and DMDS in two different manners: (1) by injecting directly the four S compounds into the GC via injector and (2) by introducing them through the PC/TD system. When a series of tests were conducted on different types of gas media (ultrapure air versus N(2)) and across varying relative humidity (RH), it was found that the RR values for the four S compounds vary from 80 to 110% range. The overall results of our study thus indicate that the RR for the PC/TD system is fairly good and that subtle differences in their RR values may reflect the combined effects of different factors investigated in this study such as types of gas media, RH change, and properties of target analytes (e.g., recovery rate of the least (H(2)S) versus the highest compound (DMDS)).
在本研究中，采用珀尔帖冷却（PC）和热脱附（TD）系统相结合的方法，对空气中还原态硫化合物（RSC）进行气相色谱（GC）分析，考察了预浓缩技术的回收率（RR）。通过两种不同方式分析包括H₂S、CH₃SH、DMS和DMDS在内的四种硫化合物的等摩尔标准品（10ppm），估算了使用PC/TD系统导致的分析物可能的损失或增加：（1）通过进样器将四种硫化合物直接注入GC；（2）通过PC/TD系统引入它们。当在不同类型的气体介质（超纯空气与N₂）和不同相对湿度（RH）下进行一系列测试时，发现四种硫化合物的RR值在80%至110%范围内变化。因此，我们研究的总体结果表明，PC/TD系统的RR相当不错，其RR值的细微差异可能反映了本研究中所考察的不同因素的综合影响，如气体介质类型、RH变化和目标分析物的性质（例如，回收率最低的（H₂S）与最高的化合物（DMDS））。
