
At 120-124 ℃, the nitrogen of nitrogen-containing compounds in the sample is converted into nitrate by alkaline potassium persulfate solution. The absorbance a220 and A275 are determined by ultraviolet spectrophotometry at the wavelength of 220nm and 275nm respectively. The corrected absorbance A is calculated according to the following formula. The content of total nitrogen (in n) is directly proportional to the corrected absorbance a. A=A220-2A275
The products meet the environmental standards HJ / t-102-2003, hj636-2012 and national standard gb11894-1989.
Th-zx400 total nitrogen water quality automatic analyzer is developed by our company, which is used to measure the concentration of total nitrogen in water. It is suitable for on-line and off-line detection of surface water, pollution source water quality, industrial and municipal wastewater and sewage.
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