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Influence of stabilizers and other components on final quality of mixtures for ice-cream production
Sládková, Veronika ; Obruča, Stanislav (referee) ; Márová, Ivana (advisor)
Presented diploma thesis was focused on study of influence of stabilizers and other components on final quality of mixtures for ice-cream production. This thesis was worked out in cooperation with Frujo Co., Ltd., Tvrdonice to find out the most suitable stabilizer with positive influence on the quality of final product. In experimental part six mixtures of stabilizers, three mixtures for ice-cream production and particular ingredients for production of mixtures for ice-cream production were analysed. Saccharides and lipids were analysed only in mixtures of stabilizers. Content of saccharides was analyzed using spectrophotometry and HPLC/RI. Lipid components were analysed by TLC. Viscosity was measured by rotatory viscosimeter and the differences of flow curves of each mixture with different stabilizers were monitored. Based on viscosity measurements some ice-creams with different stabilizers were chosen for sensory analysis. Mixture of stabilizers “Stobicol” was analysed for active compounds and antioxidant stability. Microbiological stability was tested in all of the stabilizers and also in particular ingredients including final mixture for ice-cream production. In three ice-cream mixtures of different flavour protein composition was measured by microfluidic electrophoresis. The highest content of total and reducing saccharides was determined in hydrolyzed samples. The highest values of total saccharides were found in mixture of stabilizers “Meyprogen”, the highest values of reducing saccharides were detected in stabilizer “Swissgum”. Content of triglycerides was found out almost in all of the measured mixtures of stabilizers using TLC method even though according to formulas provided by producers there should not be any. Diglycerides were detected in “Meyprogen” too even though this mixture of stabilizers should contain only saccharides. Based on results of rheology measurements and in connection with sensory analysis “Meyprogen” stabilizer could be recommended as the best material for the industrial production.
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Treatibility of surface water
Fuks, Josef ; Palčík,, Jiří (referee) ; Kučera, Tomáš (advisor)
The aim of the master´s thesis is the topic of the treatability of surface water with the focus on the process of suspension formation. For this work I took water samples from five different places around the Brno Dam which has contended with water quality deterioration for a long period. With these water samples, the series of jar coagulation tests were done with the application of three different commonly used coagulants. In the theoretical part of the master´s thesis I deal with the composition and attributes of surface water and the technology of its treatment. Each process of treatment is briefly described here with the emphasis on the process of suspension formation. The experimental part of the master´s thesis summarizes and presents the results gained through the coagulation tests in the laboratory. I evaluate the influence of different parameters on final effectiveness of water treatment and I try to find an optimal amount of coagulant, pH and speed of fast or slow mixing. Finally I compare the suitability of each coagulant and the influence of the sampling site on the effectiveness of water treatment.
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Device for magnetic stirring of suspension with ferromagnetic particles
Zítka, Jan ; Knobloch, Jan (referee) ; Červinka, Dalibor (advisor)
The aim of this work deals with the design and manufacture of a device for mixing of magnetic beads in solution by magnetic field. It is based on my previous bachelor thesis, where the device was created for one microtube (one sample). In this following work, the three improved variants for mixing and separation of 96 samples at one time were designed. The first variant of device, derived from functional prototype from bachelor thesis, was manufactured. First, the magnetic circuit and power converter were designed. Subsequently, the device was manufactured just for one microtube due to functionality testing. The third variant was realized only experimentally, the construction was designed in CAD program, and individual parts were created using 3D printer. As an alternative solution, which should be the compromise among electromagnetic and mechanical stirring, additional prototype was manufactured using 3D printer and CNC instrument. This prototype utilizes neodymium magnets and a stepper motor. The capability of magnetic beads mixing in solution was verified.
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Continual double-helicoidal mixer
Černý, Jan ; Malach, František (referee) ; Malášek, Jiří (advisor)
This work focuses on the process of mixing particulate materials and the design of the screw mixer for this activity. The theoretical part describes the mixing and properties of particulate matter. Subsequently, individual devices serving for different types of mixing are analyzed. The practical part contains calculations of the main dimensions and the required power consumption. The choice of suitable drive, bearings and gear is followed. Finally, the analysis of the blade shaft load and the strength analysis of the mixer blade using Autodesk Inventor are performed. Part of this work is enclosed drawing documentation of equipment assembly and selected partial components.
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Influence of Mixing Line Parameters Adjustment on Mixture´s Properties
Smiřický, Jan ; Kučera, František (referee) ; Petrůj, Jaroslav (advisor)
The main goal of this thesis is to set optimal rubber mixture processing parameters in Barum Continental Ltd. Dispersion is one of the most important tire production steps. Although rubber mixing has been researched by several generations of experts, there are still some unexplored influencing variables. The automotive companies are keen on the reduction of emissions and therefore pushes the tire manufactures as they can contribute to emission reduction, as well as the enhancement of tire toughness. Enhancement of tire toughness causes the decreasing of rolling resistance. Higher toughness is exhibited by tires made of rubber filled by surface modified silica. Silica filled mixtures creates a three-dimensional net which is capable to coexist with a net made by vulcanization reaction. Other goals of this thesis are to understand the process and technologies used for mixing rubber mixtures designated for tire production.
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The influence of cold RAP addition on the resulting temperature of the asphalt mixture
Bocák, Tomáš ; Hýzl, Petr (referee) ; Dašek, Ondřej (advisor)
The aim of the bachelor thesis is to simulate the effect of dosing cold reclaimed asphalt into a hot aggregate mixture, under laboratory conditions. The theoretical part will describe the possibilities of reclaimed asphalt dosing in the production of asphalt mix, together with the principles for the design of a new asphalt mix. In the practical part, by my proposed procedure, the cold portion of aggregate will be mixed with the hot portion of aggregate. The measurements will result in the final aggregate mixture temperatures and their comparison.
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Horizontální proudění vody v malých rybnících
ŠŤASTNÁ, Tereza
This bachelor thesis dealt with the flow in small ponds (specifically in pond Dehtář near the village Žabovřesky) with a focus on horizontal flow. Its aim was to perform field measurements of water movement of the surface (using devices developed by us, equipped with GPS logger) under various atmospheric conditions and from the results to determine the water flow velocity at the surface in real conditions. GPSMAP 78s, GPSMAP 60CSx and MOTOROLA phones with GPS Logger application inserted into balanced PVC pipes were used for measurements. Another objective was to create a simplified 3D model of the pond and simulate the flow in its deeper layers using Ansys software. Field measurements resulted in streamlines showing the direction of flow for the top layer of water. With wind speeds of 1-3 ms-1 in foggy and cloudy weather, the observed flow velocity was approximately 0.025 ms-1. At very low wind speeds of 0-1 ms-1 in foggy weather, the flow velocity was 0.0083 ms-1. Under variable conditions, when the surface was first slightly frozen but then melted and stronger winds from a different direction began to blow, the resulting flow velocity was first 0.025 ms-1 (at a wind speed of 0.7-1 ms-1) and later 0.0375 ms-1 (at a wind speed of 2-3 ms-1). The Ansys modelling resulted in simulations of flows in simplified ponds of two shapes (one with a sloping bottom, 0.5-4 m depth and rounded corners and the other with a constant depth of 2 m and a depression with a total depth of 4 m and rounded three corners) at different wind velocities (0.5; 1; 2; 4; 8 and 16 ms-1) and three or four wind directions. In general, the simulations showed that the flow velocity increased with wind speed, with the prevailing flow velocity being about 3% of the wind speed for all simulations. At the same time, flow velocity decreased with depth, and water was mixed to approximately 95% of the depth (up to 3.8 m). The simulations also showed the formation of eddies, here the water moved fastest where the eddies touched the edge of the pond, but in the centre of the eddies there were often areas of very low flow velocities and relatively long residence times (from seven hours to six days). The results of the field measurements and simulations in this thesis can contribute to the understanding of the processes (e.g. the effect of water mixing on oxygen, plankton and nutrient content at different areas) occurring in pond Dehtář. They may thus provide a basis for subsequent mapping of its circulation patterns, which may influence the origin and development of oxygen deficiencies and the concentration of natural food for fish and nutrients in certain parts of the pond. They can thus help to determine the suitability of areas, for example for fish feeding or sampling and thus have a positive impact on improving the management of this pond.
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Study of influence of hydrophilic carriers on the solubility of a poorly soluble drug
Veselá, Eliška ; Šklubalová, Zdeňka (advisor) ; Vraníková, Barbora (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Department of Pharmaceutical Technology Supervisor: Doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: Mgr. Jana Brokešová Student: Eliška Veselá Title of Thesis: Study of influence of hydrophilic carriers on the solubility of a poorly soluble drug The aim of this thesis was to enhance the solubility of a poorly soluble model drug meloxicam (MLX) by preparing binary interactive mixtures with hydrophilic carriers by simple mixing and co-milling. The mixtures were characterized for granulometric properties. The dissolution studies were carried out using the USP-4 apparatus assembled with a flow-through powder cell in an open-loop system. The dissolution rate rrel (min-1 ) and the amount of released drug mrel (%) were evaluated. The observable positive effect of carriers was registerred in terms of increasing the dissolution rate and the amount of released drug for both mixed and co-milled mixtures comparing to the raw drug. Mixtures with hypromellose were the exception; the improvement of the monitored parameters was not detected.
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Study of influence of hydrophilic carriers on the solubility of a poorly soluble drug
Veselá, Eliška ; Šklubalová, Zdeňka (advisor) ; Vraníková, Barbora (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Department of Pharmaceutical Technology Supervisor: Doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: Mgr. Jana Brokešová Student: Eliška Veselá Title of Thesis: Study of influence of hydrophilic carriers on the solubility of a poorly soluble drug The aim of this thesis was to enhance the solubility of a poorly soluble model drug meloxicam (MLX) by preparing binary interactive mixtures with hydrophilic carriers by simple mixing and co-milling. The mixtures were characterized for granulometric properties. The dissolution studies were carried out using the USP-4 apparatus assembled with a flow-through powder cell in an open-loop system. The dissolution rate rrel (min-1 ) and the amount of released drug mrel (%) were evaluated. The observable positive effect of carriers was registerred in terms of increasing the dissolution rate and the amount of released drug for both mixed and co-milled mixtures comparing to the raw drug. Mixtures with hypromellose were the exception; the improvement of the monitored parameters was not detected.
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