Alternating current plasma

Costanzo RB, Barry EF. 1988. Alternating current plasma detector for selective mercury detection in gas chromatography. Anal Chem 60(8) 826-829. 

Gas chromatography followed by electron-capture detection (ECD) (Gaind et al. 1992) or alternating current plasma (AGP) emission detection (Ombaba and Barry 1994) (detection limit 62 pg as manganese) has also been described for determination of MMT in gasohne. 

Ombaba JM and Barry EE. 1994. Determination of methylcyclopentadienyl manganese tricarbonyl in gasoline by capillary gas chromatography with alternating current plasma emission detection. J Chromatogr A 678 319-325. 

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. 

Fig. 43. A 3.5 MW single phase alternating current plasma torch. Reprinted from...

HPLC systems are coupled with plasma sources to determine different metallic elements. To minimize interference by other elements arsenic compounds are carried after separation into an arsine generator (HCl.NaBlTt). A complete reduction of As(III) and As(V) afibrds different molar solutions of HCl. Bottles with these solutions are changed during the run. The arsines are carried by He to an alternating current plasma source. The emissicm is measured by a monochromator at 228.8 run. Detection limits are in the range of 15-20 ppb [145]. 

ACP alternating current plasma CF-FAB continuous flow-fast atom bombardment... 

L. Colon and G. Barry, Alternating current plasma emission detection in HPLC. In Element Spedfic Chromatographic Detection by Atomic Emission Spectroscopy, Ed. by PC. Uden, ACS Symposium Series, American Chemical Sodety, Washington, DC, 1990, in press. 

Plasma-Arc Deposition. A plasma-arc is a high-intensity, low-frequency arc, generated between two electrodes by either direct or alternating current which requires a large amount of power and costly equipment. 

The gas-phase corona reactor (GPCR) uses high-voltage alternating-current fields to create a nonequilibrium plasma that destroys volatile organic compounds (VOCs) in off-gas products. 

Because an electrode does not function as electrode in DC or alternating current high-frequency discharge, the electrode system could be kept outside a glass reactor (capacitive external electrodes) or a coil around a glass tube (inductively coupled external electrode) can be used to create plasma. These modes of coupling could be dealt as a factor in the system-dependent aspect of plasma polymerization, i.e., the basic plasma polymerization remains the same. 

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