摘要
测定出口大米中铅、镉含量时，试样在高压釜中经硝酸分解后，加入适量磷酸为基体改进剂，用无火焰原子吸收法测定铅、镉元素，可提高灰化温度，即可抑制低熔点铅、镉的灰化损失，又能降低试剂空白值，消除基体干扰。导入原子吸收分光光度计中，铅、镉分别吸收２８３.３ｎｍ、２２８．８ｎｍ共振线，其吸收量与铅、镉含量成正比。该法经河南、江苏商检局验证。该方法简便可行，能满足出口商检需要。
After the sample was dissolved in the high-pressure cauldron with nitric acid,a proper amount of phosphoric acid as matrix improving agent was added,then the con- tents of lead,and cadmium were determined with atomic absorption spectrophotometer。The results showed that this method can raise ash-buring temperaturc,which prevents ashloss of lead,cadmium from low tempcrature melting points,decreases the blank value ofthe reagents,and eliminates matrix interference,inside the atomic absorption spectropho-tometer,lead and cadmium absorb 283. 3nm,228.8nm resonance lines respectively,theamount of absorption has a direct ratio wiht the lead and cadmium content of the sample。Now this method has been tested by Henan and Jiangsu。Since this mcthod is simple andeasy,it can be applied to inspections of Import and Export goods。
出处
《宁夏医学院学报》
1996年第2期22-26,共5页
Journal of Ningxia Medical College
关键词
原子吸收
商品检验
大米
铅
镉
分光光度法
spectrophotometry,atomic absorption
commodity inspection
rice
lead
cadmium
