The following is an abstract for the selected article. A PDF download of the full text of this article is available here. Members may download full texts at no charge. Non-members may be charged a small fee for certain articles.
Universal Approach for Determination of Physical and Chemical Properties of Water by Near-IR Spectroscopy
Volume 47, Number 10 (Oct. 1993) Page 1720-1727
Lin, Jie; Brown, Chris W.
Near-IR spectroscopy has been investigated as a universal approach for determination of physical and chemical properties of water and their functions of temperature. Principal component regression and multilinear regression models were used to correlate the spectra with the properties of water at temperatures between 5 and 65°C. Fifteen properties of water were investigated including density, refractive index, dielectric constant, relative viscosity, surface tension, vapor pressure, sound velocity, isothermal compressibility, thermal expansivity, thermal capacity, thermal conductivity, enthalpy, free energy, entropy, and ionization constant. Very good correlations were found between the near-IR predicted values of all the properties and those obtained by the traditional methods. This investigation demonstrates that these fifteen properties of water can be simultaneously determined simply by measuring a set of near-IR spectra of water, and, thus, near-IR spectroscopy can be used as a universal method for the determinations of physical and chemical properties of water. Remote sensing of the properties can be performed with the use of a fiber-optic sensor.