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The development of FT-Raman techniques to quantify the hydrolysis of Cobalt (III) nitrophenylphosphate complexes using multivariate data analysisTshabalala, Oupa Samuel 03 1900 (has links)
The FT-Raman techniques were developed to quantify reactions that
follow on mixing aqueous solutions of bis-(1,3-diaminopropane)diaquacobalt(
III) ion ([Co(tn)2(0H)(H20)]2+) and p-nitrophenylphosphate
(PNPP).
For the development and validation of the kinetic modelling
technique, the well-studied inversion of sucrose was utilized. Rate
constants and concentrations could be estimated using calibration
solutions and modelling methods. It was found that the results
obtained are comparable to literature values. Hence this technique
could be further used for the [Co(tn)2(0H)(H20)]2+ assisted
hydrolysis of PNPP.
It was found that rate constants where the pH is maintained at 7.30
give results which differ from those where the pH is started at 7.30
and allowed to change during the reaction. The average rate
constant for 2:1 ([Co(tn)2(0H)(H20)]2+:PNPP reactions was found to
be approximately 3 x 104 times the unassisted PNPP hydrolysis rate. / Chemistry / M. Sc. (Chemistry)
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Využití polarimetrie a refraktometrie ke stanovení koncentrace invertního cukru v invertních sirupech / Use of polarimetry and refractometry for determination of invert sugar concentration in invert syrupsMrůzková, Karolína January 2021 (has links)
Invert syrup is a liquid sweetener, which is produced by sucrose hydrolysis to form fructose and glucose. Important qualitative parameter of invert syrup is the sucrose inversion – weight percentage of invert sugar (sum of fructose and glucose) in invert syrup dry mass. This diploma thesis presents a possibility of sucrose inversion determination by polarimetry in combination with refractometry in invert syrups of 70–78 % dry mass produced at 80 °C and pH 2,4. New relationship describing the sucrose inversion as a function of polarization and refractometric dry mass was determined. The results of sucrose inversion determined using this new relationship were compared to results obtained by HPLC/RI, which was used as a reference method. The difference between these 2 determination methods was 0,1 ± 0,5 %. The new relationship was detemined with reference to the fact, that under the processing conditions, more glucose than fructose is formed. The fructose : glucose concentration ratio formed under processing conditions was observed to be equal 0,96 ± 0,02.
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