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Surface Plasmon Resonances on Colloidal Nanoparticles
Beránek, Jiří ; Brzobohatý,, Oto (referee) ; Šikola, Tomáš (advisor)
The presented diploma thesis is focused on the Localized Surface Plasmons (LSP). The far-field optical response of the colloidal solutions of gold nanoparticles caused by LSP was investigated and compared with the numerical calculations. For the simulations, the Discrete Dipole Approximation (DDA) and Finite-Difference Time Domain (FDTD) techniques were employed. In particular, the shape and size effects of spherical particles and nanorods were studied. The simulations performed by both methods are in a good agreement for the spheres. For the nanorods, the resonance was found to be affected markedly by their geometry. Also, broader resonance peaks were found. This effect was assigned to the sample size distribution and its influence is discussed by comparing the simulations with experiments. In addition, synthesis of nanorods was carried out as well. Finally, the results on the study of optical properties of silver clusters formed under equilibrium conditions are presented.
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Nanoparticles preparation by green synthesis
Kortusová, Dominika ; Valušová,, Eva (referee) ; Šimšíková, Michaela (advisor)
This thesis deals with green synthesis of noble metals nanoparticles. The first part contains secondary literature research which maps both the traditional and newly developed techniques of nanoparticles preparation. Most attention is given to the various types of green synthesis, which constitute an environmentally friendly alternative to industrially applied methods. The second part deals with the preparation of noble metal nanoparticles using tea broths. The section describes the entire synthesis process and includes photographic documentation. A total of eight colloidal solutions were prepared, four of each metal. The nanoparticles were subsequently analyzed using UV-vis spectroscopy. A time-lapse spectroscopic description of each synthesis was also undertaken. Furthermore, the size distribution of the particles by volume was measured and compared with the pictures obtained by scanning electron microscopy. The results have showed that tea broths, especially those from black tea and rooibos, are suitable for the biosynthesis of stable noble metal nanoparticles.
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Preparation of mixed colloids of humic acids with biopolymers
Ondruch, Pavel ; Pospíšilová, Ľubica (referee) ; Klučáková, Martina (advisor)
This bachelor’s thesis discusses an applicability of innovative colloidal forms of humic acids, prepared by a complexation with biopolymer chitosan. In experimental part, suitable procedures have been proposed and optimized for the preparation of hydrogels and xerogels made of these abundant polymeric substrates. In characterization of resulting materials, major attention was paid to the determination of the water content and the swelling ability. Besides, mechanical properties were studied as well. The development of a desired material aims at an industrial or agricultural utilization of sorption abilities and a tendency to immobilize various pollutants in the environment. Another advantage is represented by the ability to control the release of humic substances from the gel to environments.
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Influence of crystalloid and colloid solutions on blood coagulation using the rotational thromboelastometry (ROTEM) method
Binterová, Silvie ; Durila, Miroslav (advisor) ; Vaněk, Tomáš (referee) ; Bláha, Jan (referee)
Fluid resuscitation with crystalloid and colloid solutions is a common treatment in perioperative medicine. However, a variety of unbalanced or balanced solutions is used in clinical practice and there is still a vivid debate going on regarding the selection of optimal fluid with minimal negative effect on coagulation. The goal of the dissertation was to investigate the adverse effect of balanced crystalloids and colloids on whole blood coagulation measured by method of rotational thromboelastometry. In the first phase of the work we had assessed the adverse effect of balanced crystalloid, hydroxyethyl starch and gelatin after dilution of blood with the solution in vitro. Parametrs of EXTEM and FIBTEM tests were evaluated by using rotational thromboelastometry. In the second phase of the work we evaluated the negative effect of infusion solution after dilution in vivo. We had obtained blood samples from 30 patients during knee arthroscopy before and after administration of 500 ml of crystalloid or hydroxyethyl starch or gelatin. Parametrs of EXTEM and FIBTEM tests were evaluated by using rotational thromboelastometry.In compliance with the results of the dissertation, hydroxyethyl starch has the most obvious negative effect on clot formation followed by gelatin and finally by crystalloids. Based on...
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Influence of crystalloid and colloid solutions on blood coagulation using the rotational thromboelastometry (ROTEM) method
Binterová, Silvie ; Durila, Miroslav (advisor) ; Vaněk, Tomáš (referee) ; Bláha, Jan (referee)
Fluid resuscitation with crystalloid and colloid solutions is a common treatment in perioperative medicine. However, a variety of unbalanced or balanced solutions is used in clinical practice and there is still a vivid debate going on regarding the selection of optimal fluid with minimal negative effect on coagulation. The goal of the dissertation was to investigate the adverse effect of balanced crystalloids and colloids on whole blood coagulation measured by method of rotational thromboelastometry. In the first phase of the work we had assessed the adverse effect of balanced crystalloid, hydroxyethyl starch and gelatin after dilution of blood with the solution in vitro. Parametrs of EXTEM and FIBTEM tests were evaluated by using rotational thromboelastometry. In the second phase of the work we evaluated the negative effect of infusion solution after dilution in vivo. We had obtained blood samples from 30 patients during knee arthroscopy before and after administration of 500 ml of crystalloid or hydroxyethyl starch or gelatin. Parametrs of EXTEM and FIBTEM tests were evaluated by using rotational thromboelastometry.In compliance with the results of the dissertation, hydroxyethyl starch has the most obvious negative effect on clot formation followed by gelatin and finally by crystalloids. Based on...
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Contaminant binding to colloids in water from a mining/smelting area
Walter, Dominik ; Ettler, Vojtěch (advisor) ; Faimon, Jiří (referee)
This study deals with the association of trace elements with colloids and particles in surface waters and groundwaters of mining and smelting district of Příbram. Colloids were studied using combination of cascade filtration a tangential flow ultrafiltration method to separate individual colloid fractions. Colloids were separated by filtration membranes with nominal pore size 0,8 μm, 0,45 μm, 0,1 μm, 100 kDa, and 5 kDa. Water samples were analyzed using ICP-OES, ICP-MS and HPLC. The data were used for thermodynamic modeling using PHREEQC-2 programme. The results show that major and trace elements can be divided into several groups, based on their abundance in individual size fractions. Most elements dominate in fraction of truly dissolved matter as dissociated ions (< 5 kDa), maximum concentration in colloid fraction is 5-20 % and almost exclusively in fraction 5 kDa - 100 kDa. Gradual decrease of concentration in all fractions at low ionic strength (1,2 mmol/l) was observed in case of elements such as As, Co, Cr, Si, Sb and U. Gradual decrease of concentration in several samples was observed for Cd, Fe, Pb, Mn and Zn. Dominant binding to colloids and particles in surface waters was observed for Fe and Pb, where these fractions accounted for over 90 %. The main factor influencing colloid...
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Nanoparticles preparation by green synthesis
Kortusová, Dominika ; Valušová,, Eva (referee) ; Šimšíková, Michaela (advisor)
This thesis deals with green synthesis of noble metals nanoparticles. The first part contains secondary literature research which maps both the traditional and newly developed techniques of nanoparticles preparation. Most attention is given to the various types of green synthesis, which constitute an environmentally friendly alternative to industrially applied methods. The second part deals with the preparation of noble metal nanoparticles using tea broths. The section describes the entire synthesis process and includes photographic documentation. A total of eight colloidal solutions were prepared, four of each metal. The nanoparticles were subsequently analyzed using UV-vis spectroscopy. A time-lapse spectroscopic description of each synthesis was also undertaken. Furthermore, the size distribution of the particles by volume was measured and compared with the pictures obtained by scanning electron microscopy. The results have showed that tea broths, especially those from black tea and rooibos, are suitable for the biosynthesis of stable noble metal nanoparticles.
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Surface Plasmon Resonances on Colloidal Nanoparticles
Beránek, Jiří ; Brzobohatý,, Oto (referee) ; Šikola, Tomáš (advisor)
The presented diploma thesis is focused on the Localized Surface Plasmons (LSP). The far-field optical response of the colloidal solutions of gold nanoparticles caused by LSP was investigated and compared with the numerical calculations. For the simulations, the Discrete Dipole Approximation (DDA) and Finite-Difference Time Domain (FDTD) techniques were employed. In particular, the shape and size effects of spherical particles and nanorods were studied. The simulations performed by both methods are in a good agreement for the spheres. For the nanorods, the resonance was found to be affected markedly by their geometry. Also, broader resonance peaks were found. This effect was assigned to the sample size distribution and its influence is discussed by comparing the simulations with experiments. In addition, synthesis of nanorods was carried out as well. Finally, the results on the study of optical properties of silver clusters formed under equilibrium conditions are presented.
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Preparation of mixed colloids of humic acids with biopolymers
Ondruch, Pavel ; Pospíšilová, Ľubica (referee) ; Klučáková, Martina (advisor)
This bachelor’s thesis discusses an applicability of innovative colloidal forms of humic acids, prepared by a complexation with biopolymer chitosan. In experimental part, suitable procedures have been proposed and optimized for the preparation of hydrogels and xerogels made of these abundant polymeric substrates. In characterization of resulting materials, major attention was paid to the determination of the water content and the swelling ability. Besides, mechanical properties were studied as well. The development of a desired material aims at an industrial or agricultural utilization of sorption abilities and a tendency to immobilize various pollutants in the environment. Another advantage is represented by the ability to control the release of humic substances from the gel to environments.
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