【摘要】 <正> 一、引言为了研究辽宁省生物地球化学特性与地方病的关系,須分析飲水中及土壤浸出液中的鈣、锶、鋇等元素的含量,及他們之間的比例。对这些元素进行了定量分析,已有的化学方法和火焰光度法的灵敏度是不够的。用光譜法来分析锶、鋇則可达到較高的灵敏度。但文献中已有的鈣、锶、鋇的溶液光譜分析方法,大都不是把它們在同一次处理和摄譜中进行測定的,这是因为在測定鋇、锶时常用鈣、鎂作为內标或緩冲剂。为了簡化手續,我們希望鈣、锶、鋇能同时測定。 Hartmann等使用銅內标同时測定了鈣、锶、鋇,但測定的是高浓度的溶液。我們所分析的水样中,即使浓縮十倍以后,每毫升中含锶、鋇也只各有0.1—5微克,鈣則达每毫更多还原

【Abstract】 A spectrographic procedure using copper electrodes, a medium dispersion quartz spectrograph (Q 24), and an activated a.c. arc as light source for the determination of micro-quantities of calcium, strontium and barium in water and soil extracts is described. 300 mg sodium chloride are added to 25 ml of the solution to be determined, as spectrographic buffer; then 1 ml 0.6 N HCl, and finally 1 mg zinc (as zinc sulfate) is added as internal standard. 0.025 ml of this solution is transferred. to the upper and lower electrodes and evaporated to dryness at 55—60℃. The electrodes are excited at 6 amperes for 30 seconds. The analyticai line pairs used are: Sr4215.52/Zn4722.16, Ba4554.04/Zn4722.16, Ca442 .44/ Zn4722.16. Samples with as low a concentration as O.ly/ml may be determined with a precision of better than ±5% relative deviation, using fixed working curves. The results of the spectrographic determinarion of calcium are’in good agreement with results obtained using a chemical method. Neglecting results of very low calcium contents, the differences between results of the spectrographic method and the chemical method are usually less than ±10%. The influences of calcium and magnesium concentration upon the line intensities of barium and strontium, and the method of its elimination; the influence of solution acidity upon line intensities and the reproducibility of results are also discussed. It is found that the buffer action of sodium chloride is quite effective.更多还原