Sodium hydroxide was adopted to meltdown the sample.In the sulfuric acid,silicon and ammonium molybdate formed molybdenum yellow,with ascorbic acid molybdenum yellow was reduced to molybdenum blue.

• 采用氢氧化钠熔融分解试样,在硫酸介质中,硅与钼酸铵生成硅钼黄,以抗坏血酸还原硅钼黄为钼蓝。