Jiri Zegzulka

Optical parameter adjustment for silica nano- and micro-particle size distribution measurement using Mastersizer 2000

This paper deals with adjustment of certain optical parameters of nano and micro-structured particles of silica by which Mastersizer 2000 as a device for size distribution particle measurement has been used. The optical method process may be used by looking for unique refractive and absorption index of investigated particles. Optical properties, i.e. refractive index and absorption index of the silica have been found and related to inter-particle silica bindings in the form of Hamaker constants. For the optical properties calculations using the Mastersizer 2000 Mie Scattering solutions representing the electric and magnetic induction, i.e. silicas permeability and permittivity from Maxwells equations have been exercised.

Investigation of Samples From the High-Velocity Water Jet Driven Micro/Nano Particle Collider

The power of the high-velocity waterjets has been utilized for intentional disintegration of material particles, namely minerals. Firstly, the garnet particles were tested and studied being used usually as the most common abrasive additives for waterjets improving their cutting abilities. Later on, other mineral particles have been investigated because there are some practical applications of them. Primarily, the product generated inside the mixing chamber and the focusing tube has been studied. Subsequently, the special colliding chamber has been designed and produced enabling the collision of the two opposite moving waterjets containing material particles. This device was named “Water Jet Driven Particle Collider”, shortly WJDPC. The product created in the collision of the opposite moving particle containing waterjets has particle sizes covering partially both the nano-scale and the micro-scale. The investigation of parameters influencing the amount of particles with sizes in respective dimension scales is the topic of the contribution. Some samples of special materials were studied and tested. The discussion of the results of the computational modeling of the suction process and its influence on the final product is included. All results are discussed regarding their application in practice and further development of special routings for material particle preparation.Copyright