Vacuum monitoring plasma monitors

Alcohol sulfates and alcohol ether sulfates separated by HPLC on a styrene-divinylbenzene copolymer column with 4 1 (v/v) methanol and 0.05 M ammonium acetate aqueous solution as the mobile phase were analyzed by simultaneous inductively coupled argon plasma vacuum emission spectroscopy (IPC), monitoring the 180.7-nm sulfur line as a sulfur-specific detector [294]. This method was applied to the analysis of these surfactants in untreated wastewaters. 

Vacuum deposition techniques, such as sputtering, electron beam evaporation, and plasma deposition are common. Photopolymerization and laser-assisted depositions are used for preparation of specialized layers, particularly in the fabrication of sensing arrays. Most commercial instruments have thickness monitors (Chapter 4) that allow precise control of the deposition process. 

The tubular-type plasma reactor system used in the study consists of a reactor chamber, power supply, monomer feed, and pumping-out units, as depicted in Figure 19.1. One side of the glass tube is connected to a monomer inlet and the other side to a vacuum pump with O-ring joints. A radio frequency power generator of 13.56 MHz is coupled to two capacitive copper electrodes, which are 1 cm wide and 6 cm apart. The radio frequency power was controlled by an L-C matching network and monitored by power meter. 

Figure 1 is a block diagram of a typical radio frequency plasma system. It consists of 5 modules or functions vacuum system, power supply, matching network, power monitor, reactor center, and controller. 

Sample preparation Condition a 3 mL 200 mg Clean-Up CIS SPE cartridge (Worldwide Monitoring) with two 2 mL portions of MeOH and two 2 mL portions of water. Centrifuge plasma at 2000 rpm for 5 min prior to analysis. Mix 2 mL plasma with 20 ih 5 fig/mL IS in MeCN and 20 p,L MeCN, add 1 mL water, vortex until homogeneous, add to the SPE cartridge, wash with two 2 mL portions of acetoneiwater 20 80, wash with 1 mL 50 mM pH 2.7 phosphate buffer, place under vacuum for 3 min, elute with two 2.5 mL portions of ethyl acetate. Evaporate the eluate to dryness under reduced pressure at 40°, reconstitute the residue with 75 xL mobile phase B, vortex, add 100 lL 50 mM pH 3 phosphate buffer, centrifuge at 5000 rpm for 5 min, inject a 145 lL ahquot. 

V. Kirchoff, Advances in plasma emission monitoring for reactive DC magnetron sputtering, in Proceedings of the 38th Annual Technical Conference, Society of Vacuum Coaters 1995, p. 303. 

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