DRYING KINETICS AND PARTICLE RESIDENCE TIME IN SPRAY DRYING

A unique experimental equipment for extensive trials on the spray drying kinetics and particles residence time involving “in situ” analysis of the properties of continuous and dispersed phases was designed, built, and tested. Advanced experimental techniques (including laser techniques) to determine current parameters of spray drying process (temperature, humidity, moisture content) and current structure of spray (particle size distribution, particle velocities, etc.) were employed. Full scale spray drying tests of baker's yeast and maltodextrin enabled identification of the effect of process parameters on drying kinetics and spray residence time in the tower. Quantitative relationship describing spray drying kinetics as a function of atomization ratio and drying agent temperature were determined. The experimental results proved that spray residence time was controlled by atomization ratio and airflow rate. Drying kinetics in spray drying process is presented for the first time in the literature.     

An electrically controlled quantum dot based spin current injector

We present a proposal for a fully electrically controllable quantum dot based spin current injector. The device consists of a quantum dot that is strongly coupled to a ferromagnetic electrode on one side and weakly coupled to a nonmagnetic electrode on the other side. The presence of the ferromagnetic electrode results in an exchange field that splits the dot level. We show that this exchange-induced splitting can lead to almost full spin polarization of the current flowing through the device. Moreover, we also demonstrate that the sign of polarization can be changed by the gate or the bias voltage within a switching time in the nanosecond range. Thus, the proposed device can operate as an electrically controlled, rapidly switchable spin current source, which can be realized in various state-of-the-art nanostructures.     

Changes in properties of tar obtained during underground coal gasification process

In this study,the composition of tars collected during a six-day underground coal gasification (UCG) test at the experimental mine 'Barbara'in Poland in 2013 wa...     

Heteropolyanions doped polyimine—Preparation and spectroscopic properties

It is demonstrated that aromatic polyimine obtained by the condensation of p-phenylenediamine and terephtalaldehyde can be chemically doped with heteropolyanions of Keggin-type. The spectroscopic studies show that polyimine undergoes protonation. The structural identity of the Keggin units are preserved upon incorporation into the polymer matrix.