论文部分内容阅读
用紫外法测定水中硝酸盐已被美国列为标准方法,但易受常见化合物干扰,需进行不同的校正。我们根据硝酸盐的紫外吸收特征和双波长分光光度计的优点,对硝酸盐的吸收曲线用数学方法处理,其微分系数dA/dλ与硝酸盐的浓度有线性关系。以A/2.0毫微米为纵座标,波长(λ)为横座标作图,获得一级导数光谱,最高点在271毫微米,是吸收曲线斜率最大的地方,此波长用做λ_2,λ_1选用226毫微米,硝酸盐用氮计算时其线性范围在0—6毫克/升,检测限为0.07毫
Determination of nitrate in water by UV spectrophotometry has been the United States as a standard method, but susceptible to common compounds interfere with the need for different calibration. According to the UV absorption characteristics of nitrate and the advantages of dual-wavelength spectrophotometer, the absorption curve of nitrate is treated mathematically. The derivative coefficient dA / dλ is linear with the concentration of nitrate. A / 2.0 nm for the ordinate, the wavelength (λ) for the abscissa plot, to obtain a derivative spectrum, the highest point of 271 nm, the absorption curve is the largest slope, the wavelength used as λ_2, λ_1 use 226 nm, the linear range of nitrate is 0-6 mg / l, the detection limit is 0.07 milliliter