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Transport properties of dextran-based hydrogel systems
Vyroubal, David ; Kalina, Michal (referee) ; Klučáková, Martina (advisor)
This bachelor thesis is focused on study of transport properties of dextran-based hydrogel systems. The aim of this work is to determine their ability to absorb and release substances. Nile red was used as a probe to examine the transport properties of these systems. All hydrogels were prepared by the so-called wet way. At first stock solutions of dextran and surfactants were prepared and subsequently mixed to form a hydrogel. Nile red was dissolved in the surfactant stock solution and colored gels were formed upon mixing with dextran stock solution. Several types of gels were thus formed which differ in the concentration of the surfactant and nile red used. Supernatants were spectrophotometrically measured at various time intervals. For study of transport properties in multiple surroundings, the original supernatant was replaced after hydrogel preparation with a surfactant solution or physiological saline solution.
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Time-resolved fluorescence of system polymer-surfactant
Mondek, Jakub ; Čeppan, Michal (referee) ; Mravec, Filip (advisor)
In this diploma thesis was studied time-resolved fluorescence in polymer-surfactant system. At first aggregation numbers of cationic (cetyltrimethylammonium bromide), anionic (sodium dodecylsulfate) and nonionic (Triton X-100) surfactants were studied by steady-state and time-resolved fluorescence spectroscopy. These two methods were compared. Aggregation numbers by steady-state method were always lower than aggregation numbers measured by time-resolved method. Steady-state method of determination aggregation numbers is useless for surfactants with high aggregation number and for aerated samples. Addition of hyaluronan to surfactant system was studied. There was observed change in aggregation number after addition of hyaluronan and change in percentage of dynamic quenching after addition of hyaluronan. Hyaluronan affected aggregation number of cetyltrimethylammonium bromide and Triton X-100. Hyaluronan increased percentage of dynamic quenching in cetyltrimethylammonium bromide and in Triton X-100. Pyren in sodium dodecylsulfate was quenched by sphere of action with negligible percentage of dynamic quenching and addition of hyaluronan had no effect on quenching. As next goal of this thesis, the determination of the position of fluorescence probe pyrene in cetyltrimethylammonium bromide, sodium dodecylsulfate and Triton X-100 micelles was chosen. Position of pyrene changed with charge and structure of micelles. Next was studied how percentage of dynamic quenching by iodide compounds changes with different charge of micelle. In all cases majority of dynamic quenching was calculated.
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Purification of reverse osmosis concentrate using advanced oxidation processes
Bačovská, Leona ; Lev,, Jaroslav (referee) ; Repková, Martina (advisor)
This bachelor thesis investigates the possibility of using advanced oxidation processes (AOPs) for the degradation of surfactants in laundry wastewater reverse osmosis concentrate. The theoretical part offers an up-to-date perspective on the treatment and disposal of reverse osmosis concentrate and laundry wastewater treatment, and further explains the principle of AOPs. In the experimental part, sodium dodecyl sulfate was selected as a model anionic surfactant. The degradation of sodium dodecyl sulfate was monitored in distilled water, in artificial laundry wastewater and in a real concentrate. All experiments were conducted on a semi-operational AOP unit and the following three reaction systems were used: UV/H2O2, UV/O3 and UV/H2O2/O3. The effectiveness of all three mentioned systems was demonstrated, with a degradation in sodium dodecyl sulfate concentration of 68 – 69 % in distilled water and 53 – 56 % in artificial laundry wastewater. In the real concentrate, the UV/H2O2 system was the most effective system when there was a 73 % degradation in anionic surfactants.
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Membrane distillation based on polypropylene hollow fibers: development and testing of laboratory unit
Kalnická, Barbora ; Svěrák, Tomáš (referee) ; Kučerík, Jiří (advisor)
V súvislosti s celosvetovou krízou nedostatku vody sa odsoľovanie oceánskej vody a čistenie odpadových vôd stali veľmi dôležitými oblasťami výskumu. Cieľom tejto práce je prispieť k budúcnosti bez nedostatku pitnej vody zavedením vysoko energeticky účinného spôsobu čistenia vody, pri ktorom sa pomocou membránovej destilácie získava vysokokvalitný produkt. Táto technológia má veľký potenciál stať sa významným prínosom pre priemysel úpravy vody, ale jej plný potenciál ešte nebol využitý z dôvodu nutnosti ďalšieho výskumu. Tento článok poskytuje komplexný prehľad procesu membránovej destilácie vrátane princípov jej fungovania a rôznych typov membránovej destilácie. Okrem toho táto práca poukazuje na problémy spojené s danou technológiou a rieši ich vedecky. Experimentálna štúdia bola vykonaná s cieľom identifikovať najlepšie prevádzkové podmienky pre konkrétny typ hydrofóbnych membrán a zmierniť riziko zmáčania membrán. Z analýzy výhod a nevýhod technológie vyplýva, že hoci má membránová destilácia potenciál byť vysoko efektívna pri čistení vody, čelí obmedzeniam, ktoré je potrebné zohľadniť.
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Transport properties of dextran-based hydrogel systems
Vyroubal, David ; Kalina, Michal (referee) ; Klučáková, Martina (advisor)
This bachelor thesis is focused on study of transport properties of dextran-based hydrogel systems. The aim of this work is to determine their ability to absorb and release substances. Nile red was used as a probe to examine the transport properties of these systems. All hydrogels were prepared by the so-called wet way. At first stock solutions of dextran and surfactants were prepared and subsequently mixed to form a hydrogel. Nile red was dissolved in the surfactant stock solution and colored gels were formed upon mixing with dextran stock solution. Several types of gels were thus formed which differ in the concentration of the surfactant and nile red used. Supernatants were spectrophotometrically measured at various time intervals. For study of transport properties in multiple surroundings, the original supernatant was replaced after hydrogel preparation with a surfactant solution or physiological saline solution.
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Time-resolved fluorescence of system polymer-surfactant
Mondek, Jakub ; Čeppan, Michal (referee) ; Mravec, Filip (advisor)
In this diploma thesis was studied time-resolved fluorescence in polymer-surfactant system. At first aggregation numbers of cationic (cetyltrimethylammonium bromide), anionic (sodium dodecylsulfate) and nonionic (Triton X-100) surfactants were studied by steady-state and time-resolved fluorescence spectroscopy. These two methods were compared. Aggregation numbers by steady-state method were always lower than aggregation numbers measured by time-resolved method. Steady-state method of determination aggregation numbers is useless for surfactants with high aggregation number and for aerated samples. Addition of hyaluronan to surfactant system was studied. There was observed change in aggregation number after addition of hyaluronan and change in percentage of dynamic quenching after addition of hyaluronan. Hyaluronan affected aggregation number of cetyltrimethylammonium bromide and Triton X-100. Hyaluronan increased percentage of dynamic quenching in cetyltrimethylammonium bromide and in Triton X-100. Pyren in sodium dodecylsulfate was quenched by sphere of action with negligible percentage of dynamic quenching and addition of hyaluronan had no effect on quenching. As next goal of this thesis, the determination of the position of fluorescence probe pyrene in cetyltrimethylammonium bromide, sodium dodecylsulfate and Triton X-100 micelles was chosen. Position of pyrene changed with charge and structure of micelles. Next was studied how percentage of dynamic quenching by iodide compounds changes with different charge of micelle. In all cases majority of dynamic quenching was calculated.
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