论文部分内容阅读
2-(8-喹啉偶氮)-7-苯基偶氮-1,8-二羟萘-3,6-二磺酸〔或2-(8-喹啉偶氮)-7-苯基偶氮变色酸,QAPAC与钙形成1:1的络合物,ε值为2.5×10~5,为目前测钙灵敏度最佳的显色反应之一。加入N-十二烷基二甲氨基乙酸及邻菲咯啉可改善有色络合物稳定性,并能在较宽pH范围(4—10)内测定。实验研究了pH、试剂浓度、共存离子等对测定的影响及络合物组成比,拟定了痕量钙的分光光度分析法,并试用于雨、雪等试样中痕量钙的测定。
2- (8-quinolinylazo) -7-phenylazo-1,8-dihydronaphthalene-3,6-disulfonic acid [or 2- Azo chromotropic acid, QAPAC and calcium to form a 1: 1 complex, ε value of 2.5 × 10 ~ 5, is one of the most sensitive color reaction of calcium. The addition of N-dodecyldimethylaminoacetic acid and phenanthroline improves the stability of the colored complex and can be measured over a wide pH range (4-10). The effects of pH, reagent concentration and coexisting ions on the determination and composition ratio of the complex were experimentally studied. The trace calcium was determined by spectrophotometry. The method was applied to the determination of trace calcium in the samples such as rain and snow.