by quasiequilibrium model. Such calculations are adequate to experimental data of
CaCO
3
formation process at degassing of previously saturated with CO
2
system only
at final stage of crystallization. In dynamic model kinetic equation of CaCO
3
formation
clearly depends on all CHCS parameters but the equation form is determined by pH.
Within the range of 6 < pH < 9.5 kinetics of CaCO
3
formation is based on the reaction
Ca
2+
+ 2HCO
3
-
→ CaCO
3
↓ + HOH + CO
2
↑. It has been shown that the process is
controlled by diffusion except the time from degassing start to the moment of total
crystallization. At final stage of the process metastable CHCS state is formed.
The eleventh section “GREEN SYNTHESIS OF MONOMETALLIC
,
BIMETALLIC
NANOPARTICLES
AND
COMPOSITE
MATERIALS:
PROPERTIES AND APPLICATIONS”. In this study we report the potential use
plasma-chemical discharge and food waste such as grape skin obtained after grape
processing to produce monometallic
(AgNPs, AuNPs)
and
bimetallic nanoparticles
(Ag/Au nano-alloy). The nanoparticles were synthesised according to the rules of green
chemistry and integrating the goals of green nanotechnology. The synthesized
nanoparticles were characterized by UV–Visible spectroscopy, dynamic light
scattering. The biosynthesized AgNPs, AuNPs, and Ag-Au nano-alloy showed good
antimicrobial activity against Gram-positive and Gram-negative bacteria. AgNPs,
AuNPs, Au/Ag bimetallic nanoparticles were formed for heterogeneous and
homogeneous composites, respectively. Moreover, the different compositions of as-
synthesized Au/Ag bimetallic nanoparticles were utilized for the catalytic reduction of
4-nitrophenol.
The twelfth section “CO-PRECIPITATION METHOD IN NANOSCALE SCANDIA
STABILIZED ZIRCONIA POWDERS TECHNOLOGY FOR CERAMIC FUEL CELLS”. This paper
deals with physicochemical processes of the formation of nanostructure in stabilized
zirconia powders while obtaining it from aqueous solutions of zirconium and scandium
salts by coprecipitation method. It was established that precipitation of scandium
begins at lower pH value ( 1) than for individual scandium precipitation that occurs
at pH levels ranging from 4.5 to 6. The NMR study showed that in zirconium
hydroxides with scandium addition the removal of pore water and structural OH groups
is a major obstacle for formation of large crystals and phase transformations.
The thirteenth section “ANALYTICAL EFFECTS BASED ON INTERACTION
OF ORGANIC DYES WITH HETEROPOLY ANIONS, ANIONIC METAL
COMPLEXES AND CATIONIC POLYELECTROLYTES”. Ion association
complexes (IAs) formed between cationic or anionic organic dyes and large ions
originating from inorganic or organic compounds are widely used in analytical
chemistry. The extraction is commonly used to separate dye excess that leads to
numerous disadvantages. Non-extraction spectrophotometric methods using specific
IAs are considered. A theoretical explanation was proposed for the analytical effects
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