Showing papers on "Phosphotungstic acid published in 1991"
TL;DR: New polymeric electrodes responding to the cationic forms of tetracaine (TC), lidocaine (LD), and procaine (PC) were constructed by incorporating their ion-pair complexes into ethylene-vinyl acetate (E/VAC) copolymer, which resulted in the best linear and Nernstian response.
17 citations
Patent•
27 Jun 1991
TL;DR: In this article, the primary amine salt catalysts are separately charged to the system and oxidized with hydrogen peroxide to produce the corresponding saturated mono- and dicarboxylic acids.
Abstract: (57) [Summary] [Object] The present invention provides a method for producing a corresponding saturated mono- or dicarboxylic acid in a high yield by an oxidation reaction of an unsaturated carboxylic acid. [Structure] Unsaturated carboxylic acid selected from oleic acid, erucic acid, linoleic acid, linolenic acid or ricinoleic acid is (a) an acid selected from tungstic acid, phosphotungstic acid, molybdic acid and phosphomolybdic acid and (a) 4 The primary amine salt catalysts are separately charged to the system and oxidized with hydrogen peroxide to produce the corresponding saturated mono- and dicarboxylic acids.
6 citations
TL;DR: After treatment of epoxy resin semithin sections from glutaraldehyde fixed rat large intestine with 5% aqueous phosphotungstic acid (PTA), staining with unpurified 0.2% solutions of methyl green at 60 C for 5 min produces a color differentiation between mucin granules of goblet cells.
Abstract: After treatment of epoxy resin semithin sections from glutaraldehyde fixed rat large intestine with 5% aqueous phosphotungstic acid (PTA), staining with unpurified 0.2% solutions of methyl green at 60 C for 5 min produces a color differentiation between mucin granules of goblet cells. Some mucin granules and the glycocalyx appear deep green while the remaining granules, luminal mucin and collagen fibers are pink. The known contamination of unpurified methyl green with crystal violet seems to be responsible for the pink staining reaction of the latter structures, which also present an orange-red fluorescence under green exciting light. Electron microscopic observations show selective contrast of mucin granules which appear with a different amount of PTA deposits. This procedure is useful to reveal the heterogeneity of mucin granules in light and electron microscopy.
3 citations
TL;DR: In this paper, the collagen negative staining pattern was studied by correlating electron-optical data with chemical data, and the principal factor determining the small-scale distribution of stain in such patterns is local exclusion by "bulky" amino acid side-chains.
1 citations