二醋酸纤维素片剂水分测定的探讨

ON THE UNCERTAINTY OF MOISTURE TESTING OF CELLULOSE ACETATE FLAKES

研究了二醋酸纤维素片水分测定结果在置信水平为 95 %时的不确定度。根据对测定全过程 (包括在精度为 0 .1mg的电子天平上的称量烘箱的烘干温度、烘干时间、在干燥器中冷却时间等 )中多项误差来源 ,确定了测定的总不确定度为 0 .12 % ,对其他影响测试的因素 ,诸如实验室的环境温度和湿度、样品的粒度以及样品本身的温度等 ,也作了测定并进行讨论。

A study on the determination of uncertainty at a confidence level of 95% of the moisture testing of cellulose acetate flakes was reported in this paper. Through a thorough study of the source of errors in the course of moisture testing, including those from weighing of sample with electronic balance (precision 0.1mg), from the temperature of the drying oven set (e.g. 120℃ or 125℃), from the time of drying in the oven (e.g. 50min or 60min etc), and from the time of cooling in a dessicator (e.g. 30min, 40min or 50min etc), a totally synthesized uncertainty of 0.12% was obtained. Besides the influence of factors, e.g. the ambient temperature and humidity of the testing laboratory, the graininess of the cellulose acetate sample and also the actual temperature of the sample itself were also studied and a brief discussion was given.