Optical Properties of Aqueous Solutions of Dimethyl Sulfoxide and Application of Refractometry for Monitoring Their Composition

In line with the demands of industrial refractometric technologies, we have measured the concentration and temperature dependences of the refractive index n ( k ; t ) of aqueous solutions of dimethyl sulfoxide (DMSO), and also its temperature coefficient dn ( k ; t )/ dt . The transmission spectra of these solutions with different concentrations k = 20–90% at λ = 200–760 nm are compared with the refractive index in the visible wavelength region. We give a brief description of an optoelectronic refractometric sensor for monitoring the composition of DMSO solutions in the production line and software-based methods for adjustment and calibration of the sensor.