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Dissertation angenommen durch: Universität Duisburg-Essen, Standort
Duisburg, Fakultät für Naturwissenschaften, Institut für Chemie,
2003-07-31
BetreuerIn: Prof. Dr. Alfred Golloch , Universität Duisburg-Essen, Standort Duisburg, Fakultät für Naturwissenschaften, Institut für Chemie, Instrumentelle Analytik
GutachterIn: Prof. Dr. Alfred Golloch , Universität
Duisburg-Essen, Standort Duisburg, Fakultät für Naturwissenschaften,
Institut für Chemie, Instrumentelle Analytik
GutachterIn: Prof. Dr. Clemens von Sonntag , Leibniz-Institut für Oberflächenmodifizierung, Leipzig,
Schlüsselwörter in Englisch: ozone, Stopped-Flow, hydroperoxide, vinyl, radiation chemistry, AOP, aqueous solutions, Isomerisation, Ozonolysis
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Abstrakt in Englisch
The main focus of the dissertation is the reaction of ozone with vinyl
compounds, nucleic acids, aliphatic and aromatic carbonic acids. In
product studies, material balance with respect to ozone consumption has
been obtained. Rate constants of the reaction of ozonone with the
investigated compounds and other kinetic studies were determined with
conventional methods as well as with the Stopped-Flow method and with
the competition technique. The Stopped-Flow apparatus can be used with
optical and also with conductometric detection. Especially, while the
ozonolysis of vinyl compounds mixed anhydrides of the formic acid are
build. Except HC(O)PO32-, the hydrolysis of the investigated anhydrides
is faster than the decay. The kinetics of the hydrolysis are very
different. Also, different hydroperoxides could be detected. Their
pseudo-first-order kinetics with molybdate-activated iodide allows to
characterise a given peroxide. The halftimes of the peroxides can
differ up to seven orders of magnitude. Besides this the ozonolysis of
aliphatic unsaturated acids is described. The rate constant of this
kind of acid is pH dependent. A particularity of the ozonolysis of
fumaric and maleic acid is a marked isomerisation of these two acids
occurs. This phenomenon is unknown in the ozone chemistry so fare. The
yield of the isomerisation is pH dependent and increases with
temperature. From its high rate of reaction one has to assume that
ozone reacts with the conjugated double bond rather than with the
aromatic ring. This kinetic result could be confirmed with the result
of the product analysis. The ozonolysis of thymine and thymidine has
been investigated by a product study complemented by kinetic studies
using spectrophotometry, conductometry and stopped-flow with optical
and conductometric detection. Material balance has been obtained.
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