It has been found that tungstophosphoric acid was superior to H 2SO 4 when used as catalyst for esterification of ethyl alcohol with adipic acid.The optimum reaction conditions for synthesis of diethyl adipate catalyz...It has been found that tungstophosphoric acid was superior to H 2SO 4 when used as catalyst for esterification of ethyl alcohol with adipic acid.The optimum reaction conditions for synthesis of diethyl adipate catalyzed with tungstophosphoric acid were determined,the yield being 95.8%.展开更多
A new photochromic complex of Keggin type Tungstophosphate acid/polyacrylamide system was prepared in aqueous solution, and its thin films was made by the dip coating technique. Their properties were investigated by F...A new photochromic complex of Keggin type Tungstophosphate acid/polyacrylamide system was prepared in aqueous solution, and its thin films was made by the dip coating technique. Their properties were investigated by FT IR, UV Vis, as well as TG DTA measurement. The results showed that this type of system had different properties in solution and in thin films. ESR spectra g values for the one electron blues were the characteristic of tetragonal W 5+ complex in aqueous solution and thin films. The formation of a radical signal of ESR spectra indicated that polyacrylamide was a proton donor, the reversibility for photochromism was relative to the presence and diffusion of oxygen in polymeric network.展开更多
文摘It has been found that tungstophosphoric acid was superior to H 2SO 4 when used as catalyst for esterification of ethyl alcohol with adipic acid.The optimum reaction conditions for synthesis of diethyl adipate catalyzed with tungstophosphoric acid were determined,the yield being 95.8%.
文摘A new photochromic complex of Keggin type Tungstophosphate acid/polyacrylamide system was prepared in aqueous solution, and its thin films was made by the dip coating technique. Their properties were investigated by FT IR, UV Vis, as well as TG DTA measurement. The results showed that this type of system had different properties in solution and in thin films. ESR spectra g values for the one electron blues were the characteristic of tetragonal W 5+ complex in aqueous solution and thin films. The formation of a radical signal of ESR spectra indicated that polyacrylamide was a proton donor, the reversibility for photochromism was relative to the presence and diffusion of oxygen in polymeric network.
