Preliminary investigation of a tangential flow torch with coupling probe injector for helium microwave induced plasma mass spectrometry

A stable, low gas-flow torch has been developed for use with a helium microwave induced plasma (MIP). A toroidal plasma with central analyte introduction is obtained by the addition of a tantalum coupling probe injector tube. This injector penetrates through 100% of the total cavity depth and aids in the efficiency of power transfer to the cavity, in plasma initiation, and in circumventing the effects of a lack of homogeneity in the microwave field on analyte distribution in the plasma. The tangential helium flow was 41/min and the microwave power was 60 W.Presented in part at the 1989 European Winter Conference on Plasma Spectrochemistry, Reutte, Austria     

Microwave plasma torch analytical atomic spectrometry

The microwave plasma torch (MPT), as a relative new source, has found extensive use in atomic spectrometry. In this review, the fundamental features and characteristics of the MPT are summarized and compared with other kinds of analytical atomic sources, such as the more popularly used inductively coupled plasma (ICP), the direct current plasma (DCP), as well as other kinds of microwave plasmas (MWPs). Since the MPT offers some attractive features, it has been used as an excitation source for atomic emission spectrometry (MPT-AES), including the atomic emission detection (AED) for gas chromatography (GC), liquid chromatography (LC) and supercritical fluid chromatography (SFC). Also, it has been used either as an ionization source for atomic mass spectrometry (MPT-AMS) or an atomization source for atomic fluorescence spectrometry (MPT-AFS). The historical development and recent improvements in these MPT atomic spectrometric techniques are evaluated with emphasis on the analytical advantages and limitations. In addition, the future research directions and the application prospects of MPT atomic spectrometry (MPT-AS) are discussed.     

气动雾化进样微波等离子体炬（MPT）原子荧光光谱法测定锌的研究

本文将水溶液雾化进样与微波等离子体炬原子荧光光谱法联用,建立了HCL-MPT-AFS测定Zn的新方法。讨论了实验条件的选择问题以及溶液中共存离子对测定Zn的影响,本文所推荐的方法具有较高的灵敏度和精密度,并将其用于实际样品分析。     

微波等离子体炬耦合方式的研究

采用气动雾化连续进样、端视观测法,考察了微波等离子体炬原子发射光谱法中等离子体Ar线的背景发射以及Al,Mg,V等元素的信号发射强度随天线耦合连接点位置的不同而发生的变化.结果表明,当天线位于炬管顶端,即天线距离活塞3λ/4和λ/4时均能获得较好的等离子体,λ/4略好,信号发射强度和信背也较大,只是精密度略差一些.初步探讨了MPT炬管的电磁场结构.     

气动雾化进样时微波等离子体炬作为激发光源的性能研究

以气动雾化进样研究了微波等离子体炬（ＭＰＴ）放电作原子发射光谱法激发光源的性能，包括ＭＰＴ的获得、操作参数的影响、样品引入及其分析性能，并与微波诱导等离子体进行了比较，证明ＭＰＴ放电作激发光源有良好的分析性能．     

MPT-AES测定奶粉中的Ca和Fe

用微波等离子体(MPT)为激发光源,氩气为等离子体工作气体,用气动雾化进样,采用标准曲线法研究了微波等离子体炬原子发射光谱法(MPT-AES)测定奶粉中Ca、Fe的方法。详细考察了溶液中HCl浓度、HNO3浓度、微波前向功率、载气流量、工作气流量等实验参数对测定的影响,同时考察了共存元素钠、镁、锌对钙和铁发射强度的影响。     

流动分析技术在微波等离子体炬原子发射光谱分析中的应用

本文系统地介绍了微波等离子体煤（MPT）原子发射光谱分析技术从基础研究到商品化仪器的发展过程中流动分析技术所起的作用。论证了几项较简单技术的联用对于解决分析工作者所面临的一些复杂问题的可能性。     

Evaluation of Microwave Plasma Torch (MPT) as an Excitation Source for Determination of Mercury

The microwave plasma atomic spectrometry is an important branch of the plasma atomic spectrometry. Since the first use of microwave induced plasma(MIP) as an excitation source for spectral Chemical analysis by Broida and Chapmanin in 1958, especially the introduction of TM_(010) cavity by Beenakker in 1976 and of surfatron by Moisan in 1979 with which an atmospheric pressure helium MIP could be obtained, MIP has received considerable attention as a new excitation source for spectrometric analysis. However, since MIP suffers from the in ability to analyse the aqueous sam-     

调控微波等离子体能量进行药片活性分子结构的质谱分析

采用微波等离子体质谱(MPT-MS)技术,对替硝唑和马来酸氯苯那敏药片进行快速质谱分析.通过调控等离子体能量,在一级谱图中可得到目标物的准分子离子及丰富的碎片离子,这些碎片离子与其对应串联质谱数据基本一致,甚至更加丰富;结合标准品比对分析,最终确定这些碎片离子来自目标物而非基质.因此,MPT兼具硬电离和软电离性质,采用MPT-MS技术从一级质谱图中获得的数据可对药片中活性分子的结构进行鉴定.该方法具有快速、准确及环保等特点,在发展MPT与简单的质量分析器联用,实现质谱仪的小型化等方面有广阔的应用前景.     

微波等离子体炬发射光谱法去溶系统性能的研究

用微波等离子体矩（MPT）作激发光源，等离子体的工作气体为氩气，研究了气动雾化进样去溶系统的工作参数对分析性能的影响，探讨了水冷凝与浓硫酸吸收二者协同去溶的相关性，结果表明，OH （Q1带，带头谱线为308.520nm）的发射强度即可判别样品去溶效果。     

微波等离子体常压解吸电离质谱法快速检测化学药剂中的活性成分

构建了一种新型电离源--微波等离子体常压解吸电离源, 等离子体由微波等离子体炬产生, 工作气体为Ar气, 微波频率为2450 MHz, 该离子源可在大气压下产生稳定的等离子体. 将该电离源与具有大气压接口的Corsair API-TOF型飞行时间质谱仪结合, 实现了化学药剂中单一或多种主要活性成分的快速分析, 在手动进样条件下, 检测速度可达每小时360次. 在微波等离子体环境下, 活性物质成盐时母体化合物上结合的酸性物质可被直接除掉, 谱图中主要离子为母体化合物的准分子离子[M+H]⁺, 便于识别. 微波等离子体常压解吸电离质谱法无需化学试剂, 具有实时、 快速及无污染等特点, 为药剂研发及化学工业提供了一种新的检测技术.     

Preliminary spectroscopic experiments with helium microwave induced plasma produced in air by use of a new structure: the axial injection torch

In this experimental study we have used spectroscopic methods to characterize helium plasma obtained by means of a novel waveguide-fed microwave plasma torch at atmospheric pressure, the axial injection torch. This device produces a “plasma flame” by coupling high frequency (HF) power at 2.45 GHz to the discharge. Various flame parameters (namely the electron density number and the electron and gas temperatures) have been determined by using spectroscopic diagnostic techniques that provided an estimate in terms of the helium flow rate, absorbed HF power and axial position in the experiments. These preliminary results suggest some departure from local thermodynamic equilibrium (LTE) and seem to indicate the utility of the discharge as an excitation source for emission spectroscopy. Comparison with other microwave torches already described in the literature is made in terms of the electron density and the electron and gas temperature.     

微波等离子体炬光源基本特性的研究

用计算机化断层扫描成象技术研究了微波等离子体炬(MPT)放电的发射轮廓,证明该光源具有良好的对称性,并有一个有利于样品引入的中央通道,最佳分析区在炬管上方5～10 mm,用激光Thomson散射和Rayleigh散射技术测定了ArMPT和HeMPT放电的电子温度、电子密度和气体温度,证明MPT放电的电子温度很高而气体温度较低,是一种非热光源。其中的高能电子处于过布居状态,具有很高的激发能力。     

微波消解-微波等离子体炬原子发射光谱测定啤酒中的铜、锌、铁、锰、硒、锶

建立了微波消解-微波等离子体炬原子发射光谱(MPT-AES)法测定啤酒中微量元素。考察了微波前向功率、工作气流量、载气流量等参数,确定了MPT-AES法测定各元素的最佳实验条件。在该条件下铜、锌、铁、锰、硒、锶的检出限分别为7ng.mL-1、46ng.mL-1、13ng.mL-1、8ng.mL-1、1.2ng.mL-1、5.6ng.mL-1。相对标准偏差(RSD)均在0.9%～4.8%之间,线性范围分别为0.1～100μg.mL-1、0.5～100μg.mL-1、0.5～100μg.mL-1、0.1～100μg.mL-1、0.01～10μg.mL-1、0.05～100μg.mL-1,加标回收率均在96%～110%之间。     

Modified helium pulse-operated microwave induced plasma for spectrochemical analysis of liquid samples

To minimize problems caused by sample introduction into helium pulse operated microwave-induced plasma (He-pulsed-MIP), a simple plasma torch was developed. This torch is constructed from commonly available components with an absolute minimum of machining. In this torch, plasma is kept operating by partially isolating it from the rest of the plasma (within the plasma chamber). This auxiliary plasma is by-passed during sample or solvent injection and is therefore not affected. The design of this discharge chamber was thoroughly examined and each parameter affecting its analytical performance was evaluated. Measurements reported include effect of helium flow rate, discharge tube position and microwave power on analytical performance. Analytical calibration curves and detection limits data are shown for Ca, Cd, Cr, Cu, Fe, Mg, Ni and Zn. Plasma excitation temperature was determined using iron and copper as thermometric species. Finally, the present technique was applied to the analysis of real biological samples (liver, brain, heart, bone, kidney, tests, serum, spleen and muscles of white albino rats). The results were compared with those obtained using flame atomic absorption spectroscopy.     

用同轴表面波激励器和微波等离子体炬获得的微波等离子体的性能研究

同轴表面波激励器和微波等离子体炬是两种获得微波等离子体(MWP)的装置,本文比较了用这两种装置获得的MWP作原子发射光谱法光源时的分析性能,结果表明这两种装置各有优点,但微波等离子体炬效果更好。     

Spectroscopic characterization of a neon surface-wave sustained (2.45 GHz) discharge at atmospheric pressure

In this paper a spectroscopic study of a microwave (2.45 GHz) neon surface-wave sustained discharge (SWD) at atmospheric pressure in a quartz tube has been carried out in order to determine the plasma characteristic parameters (e.g. electron temperature and density, gas temperature, absorbed power per electron) and also to identify possible deviations from the thermodynamic equilibrium for this kind of microwave discharge. The results have been compared to experiments in the literature for other noble gas (helium and argon) SWDs generated under similar experimental conditions. Intermediate values between those of argon and helium plasmas were obtained for characteristic neon plasma parameters (temperatures and electron density). An important departure from the Saha equilibrium was exhibited by neon SWDs.     

Modified helium pulse-operated microwave induced plasma for spectrochemical analysis of liquid samples

To minimize problems caused by sample introduction into helium pulse operated microwave-induced plasma (He-pulsed-MIP), a simple plasma torch was developed. This torch is constructed from commonly available components with an absolute minimum of machining. In this torch, plasma is kept operating by partially isolating it from the rest of the plasma (within the plasma chamber). This auxiliary plasma is by-passed during sample or solvent injection and is therefore not affected. The design of this discharge chamber was thoroughly examined and each parameter affecting its analytical performance was evaluated. Measurements reported include effect of helium flow rate, discharge tube position and microwave power on analytical performance. Analytical calibration curves and detection limits data are shown for Ca, Cd, Cr, Cu, Fe, Mg, Ni and Zn. Plasma excitation temperature was determined using iron and copper as thermometric species. Finally, the present technique was applied to the analysis of real biological samples (liver, brain, heart, bone, kidney, tests, serum, spleen and muscles of white albino rats). The results were compared with those obtained using flame atomic absorption spectroscopy. Received: 3 February 2000 / Revised: 16 May 2000 / Accepted: 22 May 2000     

Determination of Cd,Pb and Sr by Microwave Plasma Torch Atomic Emision Spectrometry Using an Electrothermal Vaporization Sample Introduction System

ＩｎｔｒｏｄｕｃｔｉｏｎＥｌｅｔｒｏｔｈｅｒｍａｌｖａｐｏｒｉｚａｔｉｏｎ（ＥＴＶ）ａｓａｍｅａｎｓｏｆｓａｍｐｌｅｉｎｔｒｏｄｕｃｔｉｏｎｉｎｍｉｃｒｏｗａｖｅｉｎ－ｄｕｃｅｄｐｌａｓｍａ（ＭＩＰ）ｓｏｕｒｃｅｓｐｅｃｔｒｏｍｅｔｒｙｈａｓｂｅｅｎ...     

微波消解-微波等离子体炬原子发射光谱法测定无铅汽油中痕量铅的研究

四乙基铅作为一种良好的抗爆添加剂,曾广泛用于汽油生产中,但由于四乙基铅有很强的毒性,目前国际上已停止生产和使用车用含铅汽油,因此在生产车用无铅汽油时严格控制和准确测定铅的含量十分必要.迄今,测定汽油中铅含量的常用方法是铬酸盐容量法^[1]、一氯化碘法^[2]、X射线光谱法^[3]、分光光度法^[4,5]、原子吸收光谱法^[6]和等离子体光谱法^[7].这些方法或操作烦琐,测定时间较长^[4],或灵敏度低^[1～3],或测定误差较大,且在测试中需使用毒性较大的四乙基铅^[5],或所需的氯化甲基三辛基铵不易购买^[6],或处理过程繁琐,且仪器设备昂贵^[7].因此,建立一种简便、快速、灵敏、准确和无毒副作用的测定无铅汽油中痕量铅的方法已显得十分迫切.近年来发展的微波等离子体炬原子发射光谱法^[8]已有商品化仪器问世^[9].本文利用微波等离子体炬原子发射光谱仪研究了无铅汽油中痕量铅的测定方法,并提出用微波消解法预处理无铅汽油样品,将微波消解技术与微波等离子体炬原子发射光谱法相结合,建立了简便、快速、灵敏、准确和无污染的测定无铅汽油中痕量铅的新方法.