2019 Volume 58 Issue 6 Pages 644-650
This account summarizes our recent attempts to the visualization of the compositional distribution of chemical substances in a small mixer as well as the chlorine ion distribution on the concrete surface by novel Fourier-transformed Near-infrared (NIR) imaging spectroscopic system. The system realized the rapid and direct analysis of the compositional distribution of organic components in a mixer. The quantitative analysis of the three-component mixtures of chemicals was achieved by the measurements within several seconds, while the interpolation of the spectra by zero-filling greatly shorten the acquisition time without significant degradation of data quality. The system was also applicable for the detection of a NIR peak of Friedel's salt immobilized on a concrete surface. Because of its high sensitivity, compact size and the robustness towards the mechanical vibrations the detection of salt-damaged areas at the surface of the hollow bridge's girders was achieved by the outdoor measurements.
