Vitamin B1, also known as thiamine or antineuritic prime. A combination of the pyrimidine ring and the thiazole ring B vitamins. White crystal or crystalline powder; weak special smell, bitter, wet primer gel set, easy to absorb moisture in the air. Metamorphic break down easily in alkaline solution. Can withstand the high temperature of 100 ℃, pH 3.5 and pH greater than 5:00 prone to failure. Case of light and heat titer decline.