Features of Interaction of an Electromagnetic Radiation with Small Particles and Their Ensembles: Theoretical Aspects

Abstract

Розглянуто сучасний стан досліджень взаємодії електромагнетного випромінення з наночастинками та матрично-дисперсними системами на їх основі. Наведено основні розрахункові формули у хвильовому та електростатичному наближеннях. Проаналізовано відомі на цей час результати для окремих частинок і відповідних дисперсних систем. Виконано обговорення деяких чисельних результатів, одержаних авторами упродовж останніх років. Рассмотрено современное состояние исследований взаимодействия электромагнитного излучения с наночастицами и матрично-дисперсными системами на их основе. Приведены основные расчётные формулы в волновом и электростатическом приближениях. Проанализированы известные к этому времени результаты для отдельных частиц и соответствующих дисперсных систем. Проведено обсуждение некоторых численных результатов, полученных авторами в последние годы. The state-of-the-art of researches of interaction of an electromagnetic radiation with nanoparticles and matrix-disperse systems based on them is considered. The basic calculation formulas are given within the wave and electrostatic approximations. Known results by this time are analysed for separate particles and corresponding disperse systems. Some numerical results obtained by authors last years are discussed. Ключові слова: нанотехнології, наночастинки, ефективна діелектрична проникність, спектри вбирання.

Features of mathematical modeling of electromagnetic processing of bulk materials

“…In [3], it was mentioned in principle that the strength of the interaction of the electric field with the dielectric ball part is due to the dipole moment, which is formed when it is polarized by the same field due to the appearance of bound surface charges. A similar view on the content of the field interaction with nanoparticles was presented in [13]. It should be recognized that in this approach to the consideration of these phenomena, the actual physical essence is actually reflected.…”

“…The universality of the model is also manifested in relation to the electrophysical characteristics of the processed materials, the material of the electrodes, current conductors and any elements of electrical systems. The indicated properties are laid precisely in the integral form of interpretation of the equations of mathematical physics, represented by a combination of formulas (3)- (13). These equations operate with real physical objects -electric charges, which are located on real surfaces and interact naturally - (14), (15), (17) -at real distances.…”

“…In the processes of magnetic and electrical processing of mineral raw materials, mainly static (constant) or low-frequency alternating fields are used. Subsequently, scientific research was developed in the study of the interaction of high-frequency electromagnetic radiation with nanoparticles, matrix-dispersed systems based on them and with plane-inhomogeneous layers (coatings) that separate two homogeneous dielectric half-spaces [13][14][15]. Now for the processing of grain and other plant materials, feed and waste in animal husbandry, pulsed and high-frequency fields are also used, including microwave [16].…”

“…Visualization of the field strength heterogeneity of the electrodes Fig. 7 shows the results of the distribution of the density of secondary sources -induced charges in comparison with the primary field -obtained from equation (13). From the last diagram, one can imagine the nature of the force action of the field on the introduced particle.…”

“…However, the obtained data are sufficient to calculate the specific physical indicators of this force. So, in accordance with the chosen model, the force that the electrostatic field of the electrodes exerts on the dielectric particle introduced into it can be defined as the Coulomb interaction between this field and the charges induced by it, found from equation (13), which are located on the particle's surface [40,41]. Moreover, each component of the field E ξ creates a corresponding component of the forces that are distributed over the entire area of the boundary surface with a density:…”