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In my dissertation, I was concentrated mostly on a pliability of problematic of wheel´s suspension. My thesis is mostly a detail design proposal of a device, which is determined for a measurement and record of wheels suspension system´s elastic deformation. My theoretical part of this thesis is a search of existing devices and its problematic. The other part of my dissertation is a description of individual parts of my designed device and also an analysis of designed components´ intension. My thesis includes calculation, for case of realisation. There is also a design of measuring chain, methods of results´ evaluation after measuring with this device and theoretical analysis of measurement´s inaccuracy.

This thesis deals with the conceptual design of a trailer for transportation of Formula car SAE and experimental vehicle Formula Ford. The design of the trailer is presented in the thesis in accordance with the legislation of the Czech Republic. The trailer dimensioning is desinged in view of the anticipated loads. The main task of the thesis is the strength test of the designed trailer.

The Diploma thesis deals with segmentation of characteristic car damages, which arise during car crushes with ambient infrastructure of roads with concrete specialization to car crushes with trees and road culverts. According to chosen clash configurations there were characterized appropriate damages of front part of the car with usage of materials from real accidents. Level of damage is described according to location of the main point of impact and a speed during clash. The thesis provides summary of possible level of damage single parts of the car with focusing to front part and it gives opportunity comparison to detected damages during real car crushes with car damages made during manipulated harmful events.

Superplastic behavior of two ultrafine-grained (UFG) magnesium alloys was investigated in this thesis. Commercial Mg-4Y-3RE (wt.%) alloy was prepared by equal channel angular pressing (ECAP) and new experimental alloy Mg-23Zn-2Y (wt.%) was prepared by extrusion and ECAP. Eight passes of Mg-4Y-3RE through ECAP resulted in grain refinement down to ~340 nm and formation of a high volume fraction of fine secondary phase particles. UFG microstructure with an average grain size of 3.2 µm after extrusion and 1.6 µm after Ex-ECAP was achieved in Mg-23Zn-2Y alloy. The microstructure of Mg-23Zn- 2Y was observed by scanning and transmission electron microscopy. The thermal stability of both alloys was measured by microhardness tests. Superplastic behavior was investigated in the temperature range of 250-450 řC and strain rate range of 5x10-4 s-1 - 10-1 s-1 . The results revealed a high strain rate superplasticity in Mg-4Y-3RE alloy. Deformation to fracture exceeded 1000% for several deformation conditions, even at the strain rate of 10-1 s-1 . The highest elongation of 656 % in Mg-23Zn-2Y alloy was achieved in extruded state at the strain rate of 10-3 s-1 .

Evaluation of the tableting mixtures containing the paracetamolum by the parameters of the equation of compression The diploma thesis deals with effect of paracetamol on the parameters of compression equation. These parameters characterize compression process in the individual phases of compression: precompression phase, phase of elastic deformation and phase of plastic deformation. Paracetamolum was studied in the five mixtures, where it occurred in different ratio with microcrystalline cellulose. Looseness, Carr's index and Hausner ratio were evaluated for each mixture. The sizes of reductions ai, sizes of energies Ei and Ri, "half-pressures" pHi and the velocity constants 1/ti were calculated using three-exponential equation of compression for the individual phases of pressing. The results showed poor flow properties of tableting mixtures and thus its unsuitability for direct compression. The results of the study have revealed that increasing amounts of paracetamolum in the mixture increase reduction of volume a1 and velocity of volume change 1/t1 in dependence on the amount of the extruded air and decrease the required energy due to the smooth surface and less friction during the precompression phase. Reduction of volume a2 decrease with the increase of content of paracetamol due to...

Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Student: Natália Pribylincová Consultant: Doc. RNDr. Milan Řehula, CSc. Effect of ascorbic acid on the parameters of compression equation Many mathematical models describing the compressing process are widely used in the development of new medicinal products in form of tablets. This process can be evaluated by means of compaction equations or throughout the viscoelastic properties. Compaction equation expresses dependency on height, volume or density of the used material which is being compressed by the applied compacting pressure. Based on the gained parameters, it is possible to describe specifically various stages of the compaction process, to determine characteristic properties of the studied material and accordingly to examine its mechanism. This thesis deals with the impact of the ascorbic acid on the parameters of compaction equation. The paperwork evaluates a mixture consisting of ascorbic acid (AA) and microcrystalline cellulose (MCC) in the ratio of MCC : AA 100:0, 75:25, 50:50, 25:75, 0:100. . The mostly used compression equations are described in the theoretic part. The three - exponential equation by Řehula created at the Department of Pharmaceutical Technology at Charles...

Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Student: Tisoňová Zuzana Consultant: Doc. RNDr. Milan Řehula, CSc. Compacting process is mathematically expressed by compression equations. It is characterized by various parameters of equations. The equation expresses the dependence of the volume, density and height on compacting pressure. In this paperwork, the parameters of compacting equation are evaluated and the pre-loading phase, the phase of elastic deformation and the phase of plastic deformation are studied. This thesis deals with impact of ibuprofen on the parameters of compaction equation. Five mixtures which included microcrystalline celulose and ibuprofen in different ratio 100:0, 75:25, 50:50, 25:75 and 0:100 were studied. Results were based on the three-exponential equation. They were evaluated thanks to box plots. From the results obtained, it is obvious that with decreasing amount of microcrystalline cellulose, the parameter a1 has increased and the parameter E1 also slightly has increased. The composition of the used material didn't have any huge influence on parameters 1/t1 and pH1. During the phase of elastic deformation, the parameters a2 and E2 with decreasing amount of ibuprofen have decreased. On the other hand, the...

Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Student: Jakub Šmíd Consultant: Doc. RNDr. Milan Řehula, CSc. Effect of acetylsalicylic acid on the parameters of compression equation Compacting process can be expressed mathematically by compression equations. It is characterized by various parameters. The compression equation expresses the dependence of the volume, density and height on compacting pressure. This paper evaluates the parameters of the compaction equation and study pre-loading phase, the phase of elastic deformation and the phase of plastic deformation. This thesis examines effect of acetylsalicylic acid on the parameters of compaction equation. Tablets were compressed from five mixtures. Mixtures contained acetylsalicylic acid and microcrystalline cellulose in different ratios 0:100, 25:75, 50:50, 75:25 and 0:100. The results were obtained using the three-exponential equation. Evaluation was carried out by using box plots.

Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical technology Supervisor: Doc. RNDr. Milan Řehula, CSc. Title of Dissertation: Validation of a new method for the evaluation of stress relaxation of tablets Keywords: tablets, stress relaxation test, elastic and plastic deformation The theoretical part of this thesis deals with the elastic relaxation of tablets. It describes various methods used in the evaluation of elastic recovery of tablets. The present work explores the factors affecting the elastic relaxation of tablets. The experimental part is focused on the stress relaxation test. Until present only one delay was studied. This work studies the stress relaxation after relieving tablet. The parameters A2, T2 and P2 were reviewed. The relationship between the parameters P2 and compression force relief were studied. For experiments microcrystalline cellulose Avicel PH 102 (MCC) was used. Tablets were compressed in a device used for testing the strength of the material in pressure and tension T1-FRO 50. For the determination of the stress relaxation test, the tablets were compressed with 180 sec first delay. The second delay was always 60 sec but it was measured from certain decrease of pressure (7 kN, 6 kN, 5 kN, 4 kN, 3 kN, 2 kN, 1 kN and 0.1 kN). To...