A method for the determination of N-hydroxymethyl nicotinamide by spectrophotometry is described.N-hydroxymethyl nicotinamide was converted to acetate by acid-catalyzed acetylation,followed by base- catalyzed hydroxam...A method for the determination of N-hydroxymethyl nicotinamide by spectrophotometry is described.N-hydroxymethyl nicotinamide was converted to acetate by acid-catalyzed acetylation,followed by base- catalyzed hydroxamation of the acetate ester and color development as the ferric hydroxamate chelate.The resulting colour solution was measured at 524nm,Beer's law is obeyed in the concentration range of 1--8x10^(-3) mol/L N- hydroxymethyl nicotinamide.展开更多
A new organic aerogel made from (N-hydroxymethyl)-acrylamide (NA) and resorcinol is reported. The acidic solution of NA and resorcinol was irradiated by gamma-rays with 1200-1800 Gy dose, then was heated to 60 degrees...A new organic aerogel made from (N-hydroxymethyl)-acrylamide (NA) and resorcinol is reported. The acidic solution of NA and resorcinol was irradiated by gamma-rays with 1200-1800 Gy dose, then was heated to 60 degrees C for at least 16hr to form transparent sol-gel. The translucent aerogel can be obtained from the sol-gel with CO2 as supercritical fluid. Synthetic conditions (e.g. acidity of the solution, ratio of NA to resorcinol) are discussed.展开更多
Lyocell fibers are subject to fibrillate under wet conditions, which severely affects the appearance of this kind of fabrics. Cross-Unking treatment is an important way to prevent fibrillation of lyocell fibers. In th...Lyocell fibers are subject to fibrillate under wet conditions, which severely affects the appearance of this kind of fabrics. Cross-Unking treatment is an important way to prevent fibrillation of lyocell fibers. In this study, two kinds of traditional N-hydroxymethyl cross-linking agents were used to treat lyocell fibers and the wet abrasion values of lyocell fibers were measured in a wet abrasion test. The results show the wet abrasion values of lyocell fibers increase with the increasing concentration of the cross-linking agents, which indicates the anti-fibrillation property of the treated fibers has been improved. But the mechanical properties of the treated fibers decreased in some extent. The FT-IR spectroscopy analysis shows that the lyocell fibers have cross-linked with cross-linking agents. The SEM analysis results show the fibers treated by 4% DMDHEU or 5% SECO have good anti-fibrillation properties.展开更多
文摘A method for the determination of N-hydroxymethyl nicotinamide by spectrophotometry is described.N-hydroxymethyl nicotinamide was converted to acetate by acid-catalyzed acetylation,followed by base- catalyzed hydroxamation of the acetate ester and color development as the ferric hydroxamate chelate.The resulting colour solution was measured at 524nm,Beer's law is obeyed in the concentration range of 1--8x10^(-3) mol/L N- hydroxymethyl nicotinamide.
文摘A new organic aerogel made from (N-hydroxymethyl)-acrylamide (NA) and resorcinol is reported. The acidic solution of NA and resorcinol was irradiated by gamma-rays with 1200-1800 Gy dose, then was heated to 60 degrees C for at least 16hr to form transparent sol-gel. The translucent aerogel can be obtained from the sol-gel with CO2 as supercritical fluid. Synthetic conditions (e.g. acidity of the solution, ratio of NA to resorcinol) are discussed.
文摘Lyocell fibers are subject to fibrillate under wet conditions, which severely affects the appearance of this kind of fabrics. Cross-Unking treatment is an important way to prevent fibrillation of lyocell fibers. In this study, two kinds of traditional N-hydroxymethyl cross-linking agents were used to treat lyocell fibers and the wet abrasion values of lyocell fibers were measured in a wet abrasion test. The results show the wet abrasion values of lyocell fibers increase with the increasing concentration of the cross-linking agents, which indicates the anti-fibrillation property of the treated fibers has been improved. But the mechanical properties of the treated fibers decreased in some extent. The FT-IR spectroscopy analysis shows that the lyocell fibers have cross-linked with cross-linking agents. The SEM analysis results show the fibers treated by 4% DMDHEU or 5% SECO have good anti-fibrillation properties.
