Abstract

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.

Spectroscopy Research at the McLennan Physical Laboratories of the University of Toronto

Elizabeth J. Allin, A. D. May, B. P. Stoicheff, J. C. Stryland, and H. L. Welsh
Appl. Opt. 6(10) 1597-1608 (1967)

Nondestructive quantification of chemical and physical properties of fruits by time-resolved reflectance spectroscopy in the wavelength range 650–1000 nm

Rinaldo Cubeddu, Cosimo D’Andrea, Antonio Pifferi, Paola Taroni, Alessandro Torricelli, Gianluca Valentini, Colin Dover, David Johnson, Margarita Ruiz-Altisent, and Constantino Valero
Appl. Opt. 40(4) 538-543 (2001)

Effects of high-repetition-rate femtosecond laser micromachining on the physical and chemical properties of polylactide (PLA)

Wei Jia, Yiming Luo, Jian Yu, Bowen Liu, Minglie Hu, Lu Chai, and Chingyue Wang
Opt. Express 23(21) 26932-26939 (2015)

Accurate and rapid detection of soil and fertilizer properties based on visible/near-infrared spectroscopy

Zhidan Lin, Rujing Wang, Yubing Wang, Liusan Wang, Cuiping Lu, Yang Liu, Zhengyong Zhang, and Likai Zhu
Appl. Opt. 57(18) D69-D73 (2018)

Near-infrared spectroscopy for monitoring water permeability of optical coatings on plastics

Ulrike Schulz and Norbert Kaiser
Appl. Opt. 36(4) 862-865 (1997)