用于直接有机溶剂雾化的低功率微波诱导火焰等离子体的初步表征

Preliminary characterization of a low-powered microwave induced flame plasma for direct organic solvent nebulization.

作者信息

Ng Kin C, Bucay Phil

机构信息

Department of Chemistry, California State University, 2555 East San Ramon Ave., M/S SB70, Fresno, California 93740-8034, USA.

出版信息

Rev Sci Instrum. 2011 Dec;82(12):125101. doi: 10.1063/1.3664618.

DOI:10.1063/1.3664618

PMID:22225243

Abstract

A low powered (<90 W) microwave-induced plasma has been generated at atmospheric pressure by using a Beenakker cavity, a laboratory constructed torch, and a gas mixture of argon (400 ml/min), hydrogen (100 ml/min), and air (130 ml/min). This plasma has an excitation temperature of 3300-3500 K, electron number density of 7 × 10(14) cm(-3), and easily accepts direct methanol and ethanol introduction with a 1 ml/min solution nebulization rate. Detection limits (3σ) obtained from the atomic emission signals of Li, Sr, and Cr in water are 15, 120, and 290 ng/ml, respectively. Similarly, detection limits for the metals in methanol are 15, 120, and 260 ng/ml, respectively, and in ethanol they are 25, 360, and 330 ng/ml, respectively. The linear dynamic range is greater than three orders of magnitude.

摘要

利用贝纳克尔腔、实验室自制炬管以及氩气（400毫升/分钟）、氢气（100毫升/分钟）和空气（130毫升/分钟）的混合气体，在大气压下产生了低功率（<90瓦）的微波诱导等离子体。该等离子体的激发温度为3300 - 3500K，电子数密度为7×10¹⁴厘米⁻³，并且能够以1毫升/分钟的溶液雾化速率轻松接受直接引入的甲醇和乙醇。从水中锂、锶和铬的原子发射信号获得的检测限（3σ）分别为15、120和290纳克/毫升。同样，甲醇中这些金属的检测限分别为15、120和260纳克/毫升，乙醇中它们的检测限分别为25、360和330纳克/毫升。线性动态范围大于三个数量级。