Rapid Determination of N Isotope Labeled Nitrate Using Fourier Transform Infrared Attenuated Total Reflection Spectroscopy
Rapid Determination of N Isotope Labeled Nitrate Using Fourier Transform Infrared Attenuated Total Reflection Spectroscopy
复制标题
使用傅里叶变换红外衰减全反射光谱快速测定 N 同位素标记的硝酸盐
DOI：
10.1016/s1872-2040(13)60734-3
复制
发表时间：
2014-05-01
影响因子：
1.2
通讯作者：
Zhou Jian-Min
中科院分区：
文献类型：
--
作者：
Shao Yan-Qiu;Du Chang-Wen;Zhou Jian-Min
利用傅里叶变换红外衰减全反射 (FTIR-ATR) 光谱定量 KNO3 溶液和土壤中的硝酸盐含量、(NO3)-N-14-N 和 (NO3)-N-15-N。结果表明，溶液和土壤中硝酸盐的特征带为1200～1500 cm(-1)，(NO3-)-N-15的特征带较(NO3-)-N-14红移约35 cm(-1)。硝酸盐特征带的强度随硝酸盐浓度的增加而增强，且干扰较少。特征谱带第一主成分与硝酸盐氮含量进行线性回归，相关系数为0.9840，表明FTIR-ATR光谱技术可用于溶液和土壤中硝酸盐的快速监测。此外，基于(NO3-)-N-15吸收的红移，采用偏最小二乘法(PLS)来预测溶液和土壤中不同N同位素标记的硝酸盐-N。结果，所有的预测模型都非常出色。对于溶液中的(NO3)-N-14-N和(NO3)-N-15-N，测定系数(R-2)分别为0.9980和0.9982，相应的RPD分别为6.44和4.76。对于土壤中的(NO3)-N-14-N和(NO3)-N-15-N，决定系数(R-2)分别为0.9794和0.9679，相应的RPD分别为5.75和4.78。因此，FTIR-ATR光谱可用于快速监测溶液和土壤中不同N同位素标记的硝酸盐，为原位快速分析土壤硝化过程提供新方法。
Fourier transform infrared attenuated total reflection (FTIR-ATR) spectroscopy was utilized to quantify nitrate contents, (NO3)-N-14-N and (NO3)-N-15-N in KNO3 solution and soil. The results showed that the characteristic band of nitrate in solution and soil was 1200-1500 cm(-1), and about 35 cm(-1) of red shift was observed in the characteristic band of (NO3-)-N-15 compared with (NO3-)-N-14. The intensity of the characteristic band of nitrate increased with the nitrate concentration and with less interference involved. The linear regression was made between the first principal component of characteristic band and nitrate-N content with a correlation coefficients of 0.9840, which indicated that FTIR-ATR spectroscopy was feasible for rapid monitoring of nitrate in solution and soil. Furthermore, based on the red shift of (NO3-)-N-15 absorption, partial least squares (PLS) method was employed to predict the nitrate -N labeled with different N-isotope in solution and soil. As a result, all the prediction models were excellent. For (NO3)-N-14-N and (NO3)-N-15-N in solution, the determination coefficients (R-2) were 0.9980 and 0.9982, respectively, and corresponding RPD were 6.44 and 4.76, respectively. For (NO3)-N-14-N and (NO3)-N-15-N in soil, the determination coefficients (R-2) were 0.9794 and 0.9679, respectively, and the corresponding RPD were 5.75 and 4.78, respectively. Therefore, FTIR-ATR spectroscopy can be applied for rapid monitoring different N-isotope labeled nitrate in solution and soil, which provides a new method for in situ and fast analysis of nitrification process in soil.