论文部分内容阅读
目的对目前工作场所空气中磷酸测定的测定方法进行改进。方法用微孔滤膜采集空气样品,以酸性钼酸铵为显色剂,于45℃水浴加热20 min,在680 nm波长下比色测定。结果该方法的检出限为1.719μg,相对标准偏差为2.0%～7.0%,样品加标回收率在91.09%～93.13%之间。与国标方法比较,改进方法制作的标准系列线性很好(r=0.999 7),明显优于国际法(r=0.589 8)。结论改进方法操作简单,具有良好的重现性和稳定性,适合在基层推广应用。
Objective To improve the determination of phosphoric acid in the air in the workplace at present. Methods Air samples were collected with a microporous membrane. Acidic ammonium molybdate was used as color reagent and heated in a water bath at 45 ℃ for 20 min. The colorimetric assay was performed at a wavelength of 680 nm. Results The detection limit of this method was 1.719 μg with the relative standard deviation of 2.0% -7.0%. The recoveries of spiked samples ranged from 91.09% to 93.13%. Compared with the national standard method, the standard series produced by the improved method has good linearity (r = 0.999 7), which is obviously superior to international law (r = 0.589 8). Conclusion Improved method is simple, has good reproducibility and stability, suitable for promotion and application in the grassroots.