摘要
本文首次提出以氨水中和强酸,以铵盐-钯(Ⅱ)为联合基体改进剂测定强酸介质中铅、砷、镉、铜的方法。灰化温度提高至1000℃(Pb),900℃(As),600℃(Cd),1100℃(Cu);增感幅度为10.2—110.8％;可消除1％～4％H_2SO_4及500—4000ppm Na,500—2000ppm K,750—1000ppm Ca或1000—1200ppm Mg的干扰。方法的灵敏度和检出限分别为0.016～0.38PPb和0.02～0.32PPb;回收率为81.5％～110％;测定的相对标准偏差为0.5％～2.0％。标准食品样品的检验得到与标准值相当符合的结果。
The use of NH_3·H_2O as a matrix modifier for determination of trace Pb, As, Cd and Cu in strong acids is proposed, NH_3·H_2O acting on neutralizing strong acids has good effect on increasing sensitivity of the determination. It was studied that the action of NH_3 ·H_2O-Pd (Ⅱ) mixed matrix modifier on detecting those elements above in H_2SO_4 and the mixed modifier make ash temperature raise to 1000℃ (absorption value increase 45.3％, the same below) for Pb, 900℃ (89.2％) for As, 600℃ (110.8％) for Cd and 1100℃ (10.2％) or Cu. Large amount of (NH_4)_2SO_4 was imited in ash step and 1～4％ H_2SO_4 has no interference. The sensitivities and limits of detection are between 0.016～0.38 ppb and 0.02～0.32 ppb. Recovery rates for standard addition to multiple food samples were between 81.5～110％. Determination results of FAO/WHO contamination monitoring food samples by this method correspond to the standard values.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
1989年第8期727-730,共4页
Chinese Journal of Analytical Chemistry
关键词
铅
原子吸收光谱
基体改进剂
砷
镉
Graphite furnace atomic absorption spectrometry
matrix modifier
Lead
Arsenic
Cadmium
Copper
