After the track examinations in the store time and the conditions of the potassium tartrate solution, the paper indicated that the intercepts of the ammonia standard curves will be bigger if the store time of the reagent is longer. Then the reason is analyzed that why the colour reagent will be easily turbid and the intercept will be often too big when the ammonia standard curve is being protracted. Thus, the potassium tartrate solution speriod of validity and store method were put forward in order to more improve the measurement precision of ammonia.
Nessler's reagent colorimetric method is one of the most commonly used method of ammonia nitrogen in water content determination. Determination of ammonia nitrogen by the method of personnel are often only pay attention to the observation and use of Nessler's reagent, and ignore the storage time and storage conditions of masking agent potassium tartrate solution, 5 water and wastewater monitoring and analysis methods, this did not make provision.
The preparation of potassium tartrate solution set room temperature 24~36e preservation. Then were placed at different time of the masking agent to ammonia standard curves were drawn. Can be seen (1) as masking agent to the increase of storage time, the absorbance of each standard point gradually increased, intercept of standard curve of ammonia nitrogen increased gradually. (2) were treated with placement of 60 days of masking agent
And now formulated masking agent to simultaneously draw two ammonia standard curves (curves 4 and curve 5), the other reagents and the water are the same, the absorbance of the absorbance of a curve in each standard point were significantly higher than that of the curve in the corresponding standards point, especially three low concentration point (0mg、01005mg and 01010mg), absorbance of significantly higher, thereby causing the standard curve intercept of 4 excessive, poor accuracy.
Nessler's reagent colorimetric method is one of the most commonly used method of ammonia nitrogen in water content determination. Determination of ammonia nitrogen by the method of personnel are often only pay attention to the observation and use of Nessler's reagent, and ignore the storage time and storage conditions of masking agent potassium tartrate solution, 5 water and wastewater monitoring and analysis methods, this did not make provision.
The preparation of potassium tartrate solution set room temperature 24~36e preservation. Then were placed at different time of the masking agent to ammonia standard curves were drawn. Can be seen (1) as masking agent to the increase of storage time, the absorbance of each standard point gradually increased, intercept of standard curve of ammonia nitrogen increased gradually. (2) were treated with placement of 60 days of masking agent
And now formulated masking agent to simultaneously draw two ammonia standard curves (curves 4 and curve 5), the other reagents and the water are the same, the absorbance of the absorbance of a curve in each standard point were significantly higher than that of the curve in the corresponding standards point, especially three low concentration point (0mg、01005mg and 01010mg), absorbance of significantly higher, thereby causing the standard curve intercept of 4 excessive, poor accuracy.