Methods and Means of Measurements of the Dispersion Parameters of Particles of Suspensions in the Submicron and Nanometer Range

Abstract

Basic algorithms for processing autocorrelation functions for the method of dynamic light scattering, the most efficient method for the determination of the sizes of particles, are considered. Algorithms for processing the functions for the case of a polydisperse distribution of particles are proposed. Results of measurements of the parameters of particles in liquid media, in particular, natural mineral waters, are In view of the widespread use of nanotechnologies in different fields, such as biology, medicine, energy, electron- ics, optics, and photonics, we wish to study the problem of taking measurements of the dispersion parameters of aerosols and particles of suspensions in the nanometer range. Following the approval of State Primary Standard GET 163-2003 of the units of the dispersion parameters of aerosols, suspensions, and powdered materials, which had reproduced the dispersion param- eters in the range of particle sizes 0.5-10 µm, studies designed to improve the standard and to create a state secondary stan- dard intended for reproduction of the sizes of the units of the dispersion parameters of nanoparticles of suspensions were begun. In GET 163-2003 (1), the lower limit of measurements of the sizes of particles was expanded all the way down to 30 nm and the newly created State Secondary Standard of the units of the dispersion parameters of suspensions in the nanometer range VET 163-1-2010 assures the uniformity of measurements of nanoparticles in liquid media in the range of concentrations 10 8 -10 14 cm -3 and inspection and calibration of instruments for the measurement of the parameters of parti- cles in the range down to 10 nm (2). The measurements are based on the method of dynamic scattering of light, the primary method of analysis of the parameters of nanoparticles in liquid media. Particles of both natural and technogenic origin exert a significant effect on the processes that occur in air (3, 4) and in liquid media, which, in turn, affect the climate and ecological situation, since a significant proportion of the particles trans- ported by these media are found in the composition of the disperse phase of matter. In order to study and control the action of particles on processes that occur in natural and technogenic media, the assurance of the uniformity and reliability of mea- surements of the basic parameters of these media, such as the size (in units of length), countable concentration (expressed in terms of the number of particles per unit volume), specific surface area (expressed in terms of units of area per unit volume), and the volumetric and mass concentration (expressed in terms of the volume and mass of particles per unit volume), as well as the form, structure, and chemical or biological composition of particles is of extraordinary importance.