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This bachelor thesis deals with the comparison of drying modes mutually developed between them and their subsequent comparison with the standard. In the work, there is also theoretical analysis of humidity and temperature flow and numerical simulation process of drying wood created in a computer program COMSOL Multiphysics, which based on the finite element method. Assembled mathematical model of motion of bound moisture and temperature field in the wood is based on a set of two partial differential equations, and also on the respective boundary conditions III. regulations. Own model of the drying based on generally orthotropic material properties of wood in non-stationary diffusion of moisture and heat. It is therefore a transport model, which uses the gradient of humidity and temperature as the driving force and the material coefficients such as variables depending on the humidity, temperature, density and other essential parameters of the dried material. The main contribution of this work is the ability to improve optimization of selected drying modes with the possibility of application to the next.

Fluorescence single-molecule methods represent mighty tools for researchers in the field of structural and molecular biology. These methods are bringing in many advantages when compared to the statistical data processing of multi-molecular species. We can directly compare true statistical distributions and their kinetics. Here belongs fluorescence correlation spectroscopy, FRET and burst variance analysis. As the research advances, new methods are being developed which at the very beginning do not have proper analytical relations for data interpretation and which experimental limits we can't tell. That is the moment when the computer simulations can be used to our advantage. They can help us to specify the right direction of the future research, which is a great money-saver, while opening new perspectives and insights into the explored matter. Correct interpretation of the simulations results is key for the consequent defining of new theoretical models.

This master's thesis is focused on study of transport processes in hydrogels based on humic acids. For this purpose is used methods unsteady diffusion in cuvettes, which was studied the transport of organic dyes, specifically methylene blue and rhodamine 6G, in agarose hydrogel without the addition and with the addition of individual standards humic acids (Leonardite, Elliott Soil, Suwannee River II and Pahokee Peat). This method is based on spectrophotometric monitoring of concentration changes of dyes depending on space of the cuvette and on time. The aim of this thesis was to investigate the effects of interactions between diffusing dye and the particular type of gel to the resultant effective diffusion coefficient of dye. The experiments indicate that the presence of humic acid in the hydrogel greatly affects the transport of selected dyes.

We investigate a nonlinear reaction-diffusion system coupled with convection- diffusion system. This combined system corresponds to physical description of heteroge- neous catalysis when the flow of bulk-constituents is driven by a given stationary velocity field; diverse mechanisms between bulk- and surface-parts of the model-domain are de- scribed by Langmuir-Hinshelwood absorption kinetics; and the irreversible reactions on the catalytic walls meets the law of mass action with quadratic rate. The first part of the thesis is focused on analytical results; in Chapter 2 we prove existence and unique- ness of a mild solution for so-called near-by problem using nonlinear semigroup theory; in Chapter 3 we investigate the weak formulation of the problem. We prove an existence of a weak solution for little modified problem which, under an assumption, coincides with the original problem. In the second part of the thesis (Chapter 4) we numerically investigate the evolution of the bio-diesel microreactor. We compute numerical solutions using several methods and we test the results by analytical and physical conditions; with the aim to find the most efficient way to compute precise and physically correct solution. Keywords: heterogeneous catalysis, coupled reaction-diffusion/convection-diffusion system, nonlinear...

Hygroscopic properties of wood have significant impact on water vapor diffusion in this material. For the description of this phenomenon the water vapor permeability dependence on relative humidity or partial water vapor pressure can be used. Analytical expression of the diffusion coefficient of wood was modified in order to obtain values for the water vapor permeability. For the verification a cup method experiment at 25, 62.5 and 75% average relative humidity was performed and the results were compared to other researches. Calculated data formed the input of a numerical model, in which a stationary linear analysis with a nonlinear analysis was compared, taking the variability of diffusion properties into account in the construction details of vapor diffusion-open timber constructions. Differences in moisture fields were shown, which in some cases lead to underestimation of the risk of condensation or degradation of wood components in the building envelope, in other cases point to the actual better ability of wooden structures to divert moisture from the interior to the exterior of the building.

TBN1 is a nuclease with antitumor activity. The main goal of this work was to estimate how TBN1 and its modificated variants are stable in the ?leaf factory? system used for its production and whether it can be enhanced or influenced by chosen potential ?modificators? i. e. silencing supressors, transcription factors, glycosyltransferases and kinases. Nicotiana benthamina plants were infiltrated with the mixture of Agrobacterium tumefaciens strains bearing the nuclease plant expression vectors and co-infiltrated with the ?modifying? vectors. The nuclease and protein analyses revealed that nuclease TBN1 wt and its modificated variants are stable in the used ?leaf factory? system as to their molecular mass, only quantitative changes were detected. Expreximents showed that activity and production of the nucleases increased upon coinfiltration with silencing supressor and decreased upon coexpression with chosen transcription factor. Glycosyltransferases and kinases influenced activity and production only insignificantly. The experiments also revealed that modificated variants of TBN1 have different molecular weight suggesting that different N-glycosylation domains have different length of sugar chain and influence on nuclear activity. Our data show that this expression in planta seems to be suitable for production for study of antitumor activity of these nucleases.

This thesis examines determinants of IT investments and IT penetration rate. The full sample consists of panel data for 69 countries between years 1996 and 2013.We analyze three types of IT devices: smartphones, tablets and PCs. In order to reveal cross-segment and cross-technology differences in the importance of various determinants, separate regression models are estimated on technology-segment level. Installed base per capita, which is used to measure the level of existing capital, is included among independent variables in equations estimating per capita IT investments. Results show that the effect of the level of existing capital is stronger for smartphones and tablets when compared to PCs. Another finding is that commercial segment is less price sensitive than consumer segment. This study also provides several findings regarding other determinants of IT penetration rate and IT investments such as: national wealth, human capital, openness to trade and external knowledge, and business cycles.

This doctoral thesis is focused on design of new equipment for aeration of water surface with low depth of water column. Aeration is one of ecological preventive methods to prevent growth of cyanobacteria. Increase of dissolved oxygen content in water mass leads to support of the growth of organisms which are disadvantaged by impossibility of movement in water mass and thus also to support biodiversity. Given biodiversity has a positive effect on water quality because it avoids the outbreak of one species of aquatic organism, in particular of cyanobacteria. Designed aeration equipment uses membrane formed by hollow fibre to transport oxygen into the water. When aeration dissolution of oxygen occurs directly on the membrane surface which prevents air leak in the form of bubbles. This type of aeration has low operating costs and high efficiency of input of the oxygen into the water. Distribution in the aquatic environment is ensured by special boat. This boat is moving on the water surface and the technology is installed on the upper deck. The aeration is carried out by an aeration module situated in the water. The movement of the boat is partially ensured by autonomous control.