Sulfation plate technique

ASTM G91-86 (1986) Standard Practice for Monitoring Atmospheric SO2 Using the Sulfation Plate Technique. 

There are two accepted methods for determining the sulfur dioxide (SO2) concentration in the atmosphere of interest. Both employ the affinity of lead oxide for sulfur dioxide. The most common technique uses sulfation plates. This procedure is covered in dqtail in ASTM G 91, Test Method for Monitoring Atmo heric SO2 Using the Sulfation Plate Technique. These devices are no longer available for purchsise, but must be prepared in the laboratory. The second method is the peroxide candle, similar in its function to the chloride candle. The procedure suggests a 30-day exposure, followed by a standard sulfate analysis. This procedure is covered by ASTM D 2010, Test Methods for Evaluation of Total Sulfation Activity in the Atmosphere by the Lead Dioxide Technique. In both cases, the results are calculated as the capture rate of SO2 per unit area, normally per m. ... 

G91 SOj Using the Sulfation Plate Technique corrosion site. 

Standard Practice for Monitoring Atmospheric SO Using the Sulfation Plate Technique. Annual Book of ASTM Standards. West Conshohocken, Pa. American Society for Testing of Materials. 1997 03(02) G91-97,... 

Pulse plating techniques with symmetric or asymmetric waves have been employed for improving the deposition of CdS in acidic aqueous baths of cadmium sulfate and thiosulfate precursors [46, 47], A better control of sulfur incorporation in the deposits was reported. 

All experiments were performed on 200mm wafers using Semitool s plating tool. Trenches with various geometries and aspect-ratios were patterned in silicon oxide coated wafers. Titanium Nitride (TiN) or Tantalum (Ta) diffusion barriers with nominal thickness of 300 A were deposited on the trenches by vacuum techniques such as PVD or CVD. Unless specified differently, a PVD copper adhesion layer with a nominal thickness of 200A was deposited on top of the barrier by PVD techniques. This thin PVD copper adhesion layer was electrochemically enhanced in Semitool s proprietary ECD seed plating solution prior to the full deposition from an acid copper sulfate bath. 

The quartz plates were preliminary cleaned and hydrophilized using a standard technique ("piranha", RCA). Protamine sulfate/carboxymethylcellulose (PtS/CMC) films were fabricated by the layer-by-layer (LbL) method from 1.5 mg/mL solutions of PtS (Mw 5000) and CMC (Mw 250000) in distilled water at pH 7.0. The method is described in details elsewhere [8]. The films containing up to 20 (PtS/CMC) bilayers were used for testing of dye adsorption. 

Media employed in traditional plate checks typically include inhibitors and/or stimulators (Table 13.4). Such chemicals might include lysine, a nitrogen source that brewing yeast cannot utilize but wild yeast can copper sulfate, which is also inhibitory to strains of Saccharomyces or plates containing Actidione, which selectively promotes bacterial growth. Such techniques typically require a two-day 25° incubation period (EBC Analytica Microbiological Part 11 Continued, 1984). 

Dissolve 0.5 g of aniline in 10 mL of methylene chloride in a 50-mL Erlenmeyer flask Using a Pasteur pipette, carefully add the mixture of thionyl chloride/car-boxylic acid to this solution. Warm the mixture for an additional 5 minutes on a hot plate, add a magnetic stir bar, and stir the mixture for 20 minutes at room temperature. Then transfer the methylene chloride solution to a small separatory funnel and wash it sequentially with 2.5 mL of water, 2.5 mL of 5% hydrochloric acid, 2.5 mL of 5% sodium hydroxide, and a second 2.5-mL portion of water (the methylene chloride solution should be the bottom layer). Dry the methylene chloride layer over a small amount of anhydrous sodium sulfate. Decant the methylene chloride layer away from the drying agent into a small flask and evaporate the methylene chloride on a warm hot plate in the hood. Use a stream of air or nitrogen to speed up the evaporation. Recrystallize the product from water or from ethanol-water, using the mixed-solvents method (see Technique 11, Section 11.10). 

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