Izlaganje sa skupa

Chemistry of Interfaces with Special Respect to Precipitation Phenomena

B. Težak ; Laboratory of Physical Chemistry, Faculty of Science, University of Zagreb and Institute »Rueter Boiikovic«, 41000 Zagreb, Croatia, Yugoslavia

Sažetak

The general scheme of various investigations concerning the
equilibrated, more static, or dynamical, frequently nonequilibrated
solid/liquid/gaseous systems was pointed out approaching to the
problems of interboundary states.
The schemes for steady state of the growing crystal at the
boundary solid/liquid, the interferences in crystal growth; especially
by aggregation of primary particles into secondary structures, the
role of spacial distributions of reacting ions with concentration,
and, in general, the complexi.ty of the precipitation processes and
structures, were discussed. It was emphasized that with the transformations
from homogeneous electrolyte solutions to heterogeneous
precipitating systems the equilibrium states are very
rarely met. The 'solution aging' and 'aging of precipitates' may be
taken a,s demonstration of this fact. Therefore the diagrams showing
the time dependency of 'precipitation bodies' may be taken as a
rational approach for the characterization of the systems in
question.
For the interpretation of the phenomena as consisting of the
formation of complexes, embryos, nuclei, direct crystal growth,
and the stability/instability relationship of various entities it seems
necessary to pay full attention to the different transition stages
leading to the concentrational differences in the methorical layer
and the solution in bulk. It is assumed that such an interplay of genotypical and phenotypical factors primarily influencing the formation of 'new parts', in the Gibbs' sense, in the boundary region (methorical layer) between the solid and liquid phases is the controlling mechanism
for the formation of specific structures and the resulting properties
of emerging solids.

Ključne riječi

Hrčak ID:

197041

URI

https://hrcak.srce.hr/197041

Datum izdavanja:

15.6.1973.

Posjeta: 694 *