Microwave induced plasma source

E.H. Evans, J.J. Giglio, T.M. Castillano and J.A. Caruso, Inductively Coupled and Microwave Induced Plasma Sources for Mass Spectrometry, The Royal Society of Chemistry, Cambridge (1995). 

Inductively Coupled and Microwave Induced Plasma Sources for Mass Spectrometry 4 Industrial Analysis with Vibrational Spectroscopy 5 Ionization Methods in Organic Mass Spectrometry 6 Quantitative Millimetre Wavelength Spectrometry 7 Glow Discharge Optical Emission Spectroscopy A Practical Guide 8 Chemometrics in Analytical Spectroscopy, 2nd Edition 9 Raman Spectroscopy in Archaeology and Art History 10 Basic Chemometric Techniques in Atomic Spectroscopy... 

Barnett N. W., Chen L. S. and Kirkbright G. F. (1984) The rapid determination of arsenic by OES using a microwave induced plasma source and a miniature hydride generation device, Spectrochim Acta, Part B 39 1141-1147. 

Figure 109 Schematic diagram of an microwave induced plasma source...

Inductively Coupled and Microwave Induced Plasma Sources for Mass Spectrometry... 

Further designs of ion sources applied in plasma spectroscopy such as electrodeless microwave induced plasmas (MIPs) operating in a noble gas atmosphere at low power (mostly below 200 W) or capacitively coupled microwave plasma using Ar, He or N2 the as plasma gas (at 400-800 W) were described in detail by Broekaert.33 Microwave plasmas produced by a magnetron are operated at 1-5 GHz. Their special application fields for selected elements and/or element species are based (due to the low power applied) in atomic emission spectrometry.33... 

Figure 22-1 Mass spectrum showing natural isotopes of Pb observed as an impurity in brass. [From Y. Su, Y. Duan, and Z. Jin, Development and Evaluation of a Glow Discharge Microwave-Induced Plasma Tandem Source lor Time-ot-Fllght Mass Spectrometry," Anal. Chem. 3000, 72,5600.]...

After GC-AAS the GC coupled with microwave-induced plasma (GC-MIP) spectrometer is probably the most widely investigated hybrid system for speciation. The MIP is a low-power excitation source for emission spectrometry. In this... 

Microwave-induced plasma (MIP), direct-current plasma (DCP), and inductively coupled plasma (ICP) have also been successfully utilized. The abundance of emission lines offer the possibility of multielement detection. The high source temperature results in strong emissions and therefore low levels of detection. Atomic absorption (AA) and atomic fluorescence (AF) offer potentially greater selectivity because specific line sources are utilized. On the other hand, the resonance time in the flame is short, and the limit of detectability in atomic absorption is not as good as emission techniques. The linearity of the detector is narrower with atomic absorption than emission and fluorescence techniques. 

Alternative plasmas have been occasionally used for elemental speciation analysis, including the microwave-induced plasma (MIP), which has been reviewed in Ref. [7] and the low-power helium plasma. Both of these plasma sources have the advantage of reduced gas and power consumption over the traditional ICP however, the use of these plasmas with interfaces with CE has been... 

Olson, L.K. Caruso, J.A. The helium microwave-induced plasma—An alternative ion-source for plasma-mass spectrometry. Spectrochim. Acta, Part B 1994, 49, 7-30. 

Kollotzek D., Tschopel P. and Tolg G. (1984) Three-filament and toroidal microwave induced plasmas as radiation sources for emission spectrome-tric analysis of solutions and gaseous samples. II. Analytical performance, Spectrochim Acta, Part B 39 625—636. 

Satzger R. D., Fricke F. L., Brown P. G. and Caruso J. A. (1987) Detection of halogens as positive ions using a He microwave induced plasma as an ion source for mass spectrometry, Spectrochim Acta, Part B 42 705-712. 

Plasma sources are capable of producing intense emission from the elements. Types of plasma used in chromatographic detection are microwave induced plasmas (MIP) and inductively coupled plasma (ICP). An argon plasma is sustained in a microwave cavity which focuses into a capillary discharge cell. The most widely used cavities are cyhndrical resonance cavities and surfatron that operates by surface microwave propagation along a plasma column. Atmospheric pressure cavities are very simple to interface with capillary GC columns. 

During the 1980s, a rapidly increasing number of methods have been published for mercury determination by AES (often called OES = optical emission spectrometry) after excitation/ionization in a gas plasma, usually argon. The plasma source most frequently used is an ICP, but also other kinds of plasma sources are used, e.g. alternating current plasma (ACP), direct current plasma (DCP), and microwave-induced plasma (MIP). AES has a wide multi-element capability the linear range extends over 4-6 orders of magnitude. 

Such large amounts of data can only be sensibly and rapidly analysed and compared with reference spectra using microprocessors such as the fast 32 bit processors in PCs. The main systems in use today are discussed below, and in addition to the above mentioned techniques the microwave induced plasma (MIP) detector, a helium microwave plasma emission source coupled to a GC and an optical emission spectrometer are reviewed. 

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