论文部分内容阅读
目的:提高游泳池水中尿素的检测质量,使二乙酰一肟法得到更好的应用。方法:将原法二乙酰一肟溶液浓度2 g/L改为10 g/L的固体量直接加到安替比林溶液中溶解(DMA显色液);水样10 ml加DMA2 ml沸浴1 h后冷却,纯水定容至25 ml测定。并考察两法制备的不同浓度二乙酰一肟及使用透明管与遮光管对显色的影响。结果:二乙酰一肟乙酸溶液与无乙酸的DMA显色液,其透明管与遮光管测定的吸光度,放置30 min平均下降了6.80%、1.30%与1.44%、0.98%;放置60 min平均下降了19.8%、1.92%与2.49%、1.60%。本法工作曲线在0~50μg范围内符合Beer定律。结论:原法乙酸是影响显色稳定性的主要因素。本法弃用乙酸,简化试剂加入步骤,可用透明管操作,线性范围及吸光度分别是原法的3.3倍及5倍,相关系数r>0.9995,且对尿素较高浓度的水样可显色后稀释测定,优于原法。
Objective: To improve the detection quality of urea in swimming pool water and make diacetyl-oxime method get better application. Methods: The original diacetyloxime solution concentration of 2 g / L to 10 g / L of solids directly added to the antipyrine solution dissolved (DMA reagent color); water samples 10 ml plus DMA2 ml boiling bath 1 h after cooling, water volume to 25 ml determination. The effects of different concentrations of diacetyl-oxime prepared by the two methods and the use of transparent tubes and shading tubes on the color development were investigated. Results: The absorbance of diacetyl-oxime acetic acid solution and DMA-free color-developing solution of acetic acid decreased by 6.80%, 1.30% and 1.44%, 0.98% on average for 30 min after being placed in the transparent tube and shading tube, respectively. 19.8%, 1.92% and 2.49%, 1.60% respectively. The working curve of this method is Beer’s law in the range of 0 ~ 50μg. Conclusion: The original method of acetic acid is the main factor affecting the color stability. The acetic acid was discarded in this method, which simplifies the reagent addition step and can be operated with a transparent tube. The linear range and absorbance are respectively 3.3 times and 5 times of the original method with the correlation coefficient r> 0.9995. Dilution of measurement, better than the original method.