[Reflectance characteristics of rare earth solution with different concentrations]

In the present paper, ten aqueous samples which contain-different concentrations of REE were collected in south Jiangxi province, and the reflectance spectra and the concentrations of REE were measured by analytical spectral devices (ASD) FieldSpec-3 reflectance spectroscopy and inductively coupled plasma mass spectrometry (ICP-MS), respectively. The results show that the spectra presented mix characteristics of pure water and rare earth oxide. In addition, six diagnostic absorption features caused by REE in visible and near-infrared wavelengths were detected. Then, relative absorption depths of the six absorption wavelength were calculated by the ratio spectra of sample spectra and pure water spectra. Finally, concentrations of total REE of ten samples and relative absorption depths of the six absorption wavelength were selected as two factors, and their relationship was perfectly described using linear regression analysis in which correlation coefficient was up to 96%-97%. The study provides a new method for quantitative estimation of different concentrations of dissolved REE in aqueous media, and strengthens theoretical basis for hyperspectral information extraction of REE.