The esterification of oleic acid was applied in order to screen the suitability a series phosphotungstic-based Wells-Dawson types compounds as potential catalysts heterogeneous transesterification sunflower waste cooking oil. This test reaction indicated that phosphotungstic heteropolyacid H6P2W18O62·xH2O, dispersed on titania oxide loading 15 mg per m2 support (named 42% HPA/TiO2) and possessi...

The production of carboxylic acids by partial wet oxidation of alkali lignin at elevated temperatures and pressures was studied experimentally. Two different heteropoly acids, phosphotungstic acid (H₃PW12O40) and phosphomolybdic acid (H₃PMo12O40), were used to catalyze the oxidation of lignin under hydrothermal conditions. Factors influencing the total yield of carboxylic acids formed during th...

Epizootic diarrhea of infant mice virus has been purified from the intestines of infected mice using enzymatic digestion, precipitation with polyethylene glycol, extraction with Genesolv-D, and sucrose step-gradient centrifugation. The purified virus was found to be stable at -70 C or when treated with ether, chloroform, or sodium deoxycholate. Biochemical analysis of purified virions has sugge...

By controlling the alkalinity and the amount of phosphotungstic acid (PTA), turbidity and gelling in the final colored solution obtained in the reaction between uric acid and PTA in the presence of sodium glycerol silicate (NaGS) can be eliminated without using antiturbidity reagents. The optimum range of alkalinity is 0.55-0.76 mEq. of excessalkali in a total volumeof 7.75 ml. A modification o...