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11	Lomová houževnatost kompozitu s polymerní matricí / Fracture Toughness of Composite with Polymeric Matrix Hofírková, Linda January 2009 (has links) This diploma work deals with relationship between composition and mechanical properties of polymeric composite with polypropylene matrix and magnesia hydroxide as a filler. The influence of content of filler (20,40,60 w.%) and temperature (-30°C +60°C) on dynamic fracture toughness is observed. The regresion function describing the dependence of studied mechanical properti on temperature for all experimental materials where found. Experimental data were confront with data gained on the same materials then 10 years ago and influence of time on mechanical properties of follow - up composites is evaluate.
12	Neutralizace kyselých roztoků / Neutralization of acid solutions Pavlík, Ondřej January 2013 (has links) The present thesis is concerned with neutralization of acid groundwater after the hydrochemical uranium mining in the area of Stráž pod Ralskem. In the thesis is briefly described progression of the hydrochemical uranium mining and follow-up negative impacts on the environment. There is described the technology involved in its disposal. This is followed by the design calculation of major apparatus technology associated with neutralization of acid solutions. Output of technology is determined by the mass balance. The results are the main dimensions of the apparatus, mechanical parts and electric power each device.
13	Studium jevů limitujících životnost sekundárních článků Ni-Zn / A Study of Phenomena that Limit the Life-Span of Ni-Zn Secondary Cells Chladil, Ladislav January 2014 (has links) This dissertation is focused on the study of selected additives and their effect on positive and negative electrodes of Ni-Zn secondary cells. The first group of additives consists of the inorganic compounds that reduce zinc oxide solubility and thus prevents shape changes of the zinc electrode. The second group contains organic additives that have the beneficial effect of dendrite growth prevention. All additives were examined in relationship to their compatibility with the positive electrode and to their effect on the zinc electrode dendrites inhibition, hydrogen evolution and corrosion inhibition. Moreover, the study of decomposition kinetics of supersaturated zincate solution with the first group of additives was performed. Finally, a short study of pulse regime charging mode with regard to dendrites inhibition was performed and evaluated.
14	Modifikace hydroxidu nikelnatého pro zlepšení jeho elektrochemických vlastností v alkalických akumulátorech / Intensification of Nickel Hydroxide Properties in Order to Improvement of Its Electrochemical Behavior in Alkaline Accumulators Máca, Tomáš January 2015 (has links) Commercial alkaline accumulators with positive electrode based on nickel hydroxide generally comprise beta modification of the active material at present due to its excellent stabilization of performance during electrochemical cycling. This dissertation refers to a research work accomplished by author, which has been aimed to utilization of alpha nickel hydroxide in alkaline batteries including exploration of possibilities to attain its stability in strong alkali medium of the electrolyte. I have focused my effort to elucidate reasons for its transformation tendency and to find way of their suppression.
15	Vliv příměsi kobaltu na parametry kladné elektrody Ni-Cd akumulátorů / The influence of cobalt additive on parameters of positive electrode for Ni-Cd accumulators Svoboda, Michal January 2009 (has links) The Master´s thesis deals with description of the influence of cobalt additive on positive electrode parameters for Ni-Cd accumulators. Trough the use of Electrochemical Quartz Crystal Microbalance are analysed the effects which decline effective life of positive electrode during accelerated cycling. Theoretical part describes important characteristics of Ni-Cd accumulators, the working principle and effects which are in progress on positive electrode during cycling. The next part deals with description of system EQCM and the pricnciples of doping active mass with cobalt additive. Practical part consists of EQCM system calibration and electrochemical measurements. The principal aim is detection of the influence of cobalt additve on active mass during cycling in different electrolytes. From the results of measurements is set the optimal amount of cobalt additive.
16	Studium hydroxidů a oxidů kovů ve vodných roztocích / Study of Metal Oxides and Hydroxides in Aqueous Solutions Špičák, Petr January 2011 (has links) This dissertation work deals with analysis of nickel hydroxide phases, their oxidation compounds, their stability and degradation mechanisms of electrochemically more active alpha phase on standard beta phase. The active material was prepared by both methods, electrodeposition and chemical precipitation. Main analysis method was Electrochemical Quartz Crystal Microbalance in combination with common analytical methods (cyclic voltammetry, potenciometry) can resolute between alpha and beta phases and quantitatively describe differences in main reaction by monitoring mass changes in the active material. Poor stability of the ?-Ni(OH)2 were improved by adding cations with valence two three and four into the structure instead of Ni atoms. The most important role plays cobalt and its hydroxide. Totally new way is to use titanium in combination with other cations. In electrolyte the most significant addition is LiOH, which has beneficial influent on cycle ability, stability in strong alkaline medium and cycle life.
17	Využití molekulárních simulací při komplexní strukturní analýze vrstevnatých materiálů / Application of Molecular Simulations in Complex Structural Analysis of Layered Materials Veteška, Marek January 2015 (has links) Title: Application of Molecular Simulations in Complex Structural Analysis of Layered Materials Author: RNDr. Marek Veteška Department: Department of Chemical Physics and Optics Supervisor: RNDr. Miroslav Pospíšil, Ph.D., Dept. of Chemical Physics and Optics Abstract: Techniques of molecular simulations were used together with experimental measurements (X-ray diffraction, thermogravimetry, infrared spectroscopy, elemental analysis and others) to clarify the structure properties of various types of layered materials. The structure of Zn-Al-layered double hydroxide intercalated by pyrenetetra- sulfonate acid was solved. Depending on the relative humidity, the samples showed different arrangements with three planes of water molecules and with either one or two planes of pyrenetetrasulfonate anions. At the same time considerable variability of anions arrangement was demonstrated. The adsorption behavior of natural montmorillonite and montmorillonite modified by tetramethylammonium cations in relation to aniline and phe- nol was explored. Adsorption features differed according to both the type of adsorbed molecules and the type of adsorbents. An important role was played by the plane of water molecules right above the surface which medi- ated adsorption of anilines. The water plane area was reduced by...
18	Vliv namáhání alkalických akumulátorů na jejich parametry / The influence of alcaline accumulators loading on their parameters Čech, Ondřej January 2009 (has links) This master's thesis deals with alkaline battery characteristics and it has special consideration of nickel-cadmium cells. There are three main experimental parts in this paper. First one is concerned with positive electrode materials properties and is aimed to investigate impact of magnesium ions formed into nickel hydroxide electrode structure. Second part deals with battery charging/discharging and response measurement tool design. National Instruments hardware PXI modules for data acquisition was used and program in LabView environment was made. Last one is concerned with nickel-cadmium cell properties changes during increased temperature stressing. Investigation of cell self-charge changes during lithium hydroxide addition into electrolyte was made.
19	Germanium-, Tin-, Lead-, and Bismuth-Containing <i>β</i>-Diketiminato Complexes for the Synthesis and Structural Characterization of Hydroxide, Carboxylic Acid, Heterobimetallic Oxide, Transition Metal-Main Group, Hydride and Halide Compounds / Germanium-, Tin-, Lead-, and Bismuth-Containing <i>β</i>-Diketiminato Complexes for the Synthesis and Structural Characterization of Hydroxide, Carboxylic Acid, Heterobimetallic Oxide, Transition Metal-Main Group, Hydride and Halide Compounds Pineda Cedeno, Leslie William 03 May 2006 (has links) No description available. 540 Chemie Mathematics and Computer Science Blei Carboxylsäure Germanium Hydride Hydroxid Zinn Wismut Bismuth Carboxylic acids Germanium Hydrides Hydroxides Lead Tin 35.60 STM 300: Germanium {Anorganische Chemie} STM 350: Zinn {Anorganische Chemie} STM 400: Blei {Anorganische Chemie} STN 400
20	Studium částic různých kosmetických pigmentů / Study of particles of various cosmetic pigments Cerevatova, Kristina January 2020 (has links) The main focus areas of this master thesis include the writing of a literature review, which contains an overview and segregation of pigments which are used in the preparation of cosmetic products. The thesis is focused on the properties and characterization of pigments for use in cosmetology. The following focus is on legislation, more specifically on pigments that the cosmetic industry allows, limits and does not allow. The main part of this thesis is an overview of methods for the characterization of pigments. The practical part deals with the characterization of particles of selected cosmetic pigments by applying methods for determination of color, elemental and phase composition, particle size and morphology. The thesis is concluded by evaluation of the achieved results.

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