摘要
乳粉样品用硝酸在120℃温度下加压消化4 h,所得溶液定容为50 mL,分取部分样品溶液经活性炭脱色后取其滤液用磷钒钼三元杂多酸光度法测定磷,另取部分试样溶液用FAAS法测定钙。称取同一样品6份,按方法测定磷及钙作精密度试验,并用标准加入法做回收试验。磷测定结果的相对标准偏差为1.2%,加标回收率在88.9%～92.7%之间;钙测定结果的相对标准偏差为0.60%,加标回收率在96.6%～103.0%之间。
Sample of milk powder was digested with cone. HNO3 under pressure at 120 ℃ for 4 h, and the solution obtained was diluted to 50 mL in a volumetric flask used for determination of phosphorus and calcium. An aliquot of the sample solution was taken and mixed with an appropriate amount of activated carbon to remove its color. After separation of activated carbon by filtration, phosphours was determined in the filtrate by the phosphovanadomolybdate-photometric method. Another aliquot of the sample solution was taken for determination of calcium by FAAS. Six portions of a same sample were analyzed for P and Ca contents to test for precision of the method. Values of RSD＇s found were 1.2% for phosphorus, and 0. 6% for calcium. Values of recovery found for phosphorus and calcium by standard addition method were in the ranges of 88. 9%-92. 7% and 96.6%-103. 0% respectively.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2009年第1期75-76,78,共3页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
