Its ninhydrin reaction was negative, but after acid hydrolysis, its ninhydrin reaction and biuretreaction were positive.
茚三酮反应呈阴性，用酸水解后茚三酮反应和双缩脲反应呈阳性。
2
Methods for the modification of isocyanates include process of urethane, dimerization, trimerization, biuret, carbodiimide, and blocking reaction, etc.
异氰酸酯的改性方法包括氨酯改性、二聚改性、三聚改性、缩二脲改性、碳化二亚胺改性和封闭改性等。
3
Method U. S Standardization Com mission's standard file EP10-T2 was used to select representative ALT and TP. AL T was determined with the enzyme reaction, TP was determined with biuretreaction .