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Liquid aprotic electrolytes with TiO2 a Al2O3 nanoparticles
Tomeš, Petr ; Krejza, Ondřej (referee) ; Sedlaříková, Marie (advisor)
The first part of this diploma thesis is dealing with conductivity of liquid electrolytes. The second part is about third generation gel electrolytes and thein conductivity. The electrolytes were inorganic salts LiClO4, LiBF4 and NaClO4 in an aprotic propylene carbonate (PC) -used as a solvent. Nanosized Al2O3 and TiO2 particles were, proportionally to the sample's volume, added to the both – blend and gel samples in an amount expressed by weight percentage (wt). Both liquid and gel electrolytes contained following amount on nanosorbent: 3,46% wt, 7,17% wt, 10,0% wt and 12,0% wt. The liquid electrolytes were gelled using commercially available precursor Superacryl (Spofa dental s.r.o.).
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Study of gel electrolytes properties by MR methods
Mrnka, Michal ; Gescheidtová, Eva (referee) ; Bartušek, Karel (advisor)
Theoretical part of the work deals with explanation of nuclear magnetic resonance phenomenon, relaxation processes in system of nuclear spins, basic techniques for measurement of relaxation times. There are described diffusion and techniques for diffusion coefficient measurement including method for suppressing the background gradient. Experimental part describes preparation of gel electrolytes samples and measurement of relaxation times. Sodium salt was used as a conductive agent. There is interpreted dependence of relaxation times on polymerization times and on concentration of conductive agent in gels.
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Study of gel electrolytes properties by MR methods
Mrnka, Michal ; Gescheidtová, Eva (referee) ; Bartušek, Karel (advisor)
Theoretical part of the work deals with explanation of nuclear magnetic resonance phenomenon, relaxation processes in system of nuclear spins, basic techniques for measurement of relaxation times. There are described diffusion and techniques for diffusion coefficient measurement including method for suppressing the background gradient. Experimental part describes preparation of gel electrolytes samples and measurement of relaxation times. Sodium salt was used as a conductive agent. There is interpreted dependence of relaxation times on polymerization times and on concentration of conductive agent in gels.
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Liquid aprotic electrolytes with TiO2 a Al2O3 nanoparticles
Tomeš, Petr ; Krejza, Ondřej (referee) ; Sedlaříková, Marie (advisor)
The first part of this diploma thesis is dealing with conductivity of liquid electrolytes. The second part is about third generation gel electrolytes and thein conductivity. The electrolytes were inorganic salts LiClO4, LiBF4 and NaClO4 in an aprotic propylene carbonate (PC) -used as a solvent. Nanosized Al2O3 and TiO2 particles were, proportionally to the sample's volume, added to the both – blend and gel samples in an amount expressed by weight percentage (wt). Both liquid and gel electrolytes contained following amount on nanosorbent: 3,46% wt, 7,17% wt, 10,0% wt and 12,0% wt. The liquid electrolytes were gelled using commercially available precursor Superacryl (Spofa dental s.r.o.).
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Study of gel electrolytes properties by MR methods
Kořínek, R. ; Vondrák, Jiří ; Bartušek, Karel ; Mrnka, M.
In this paper are introduced basic methods for measuring the properties of the gel structure during polymerization, particularly relaxation times T1, T2 spin density and diffusion coefficients. We can obtain these parameters using the MR pulse sequences. To measure of relaxation time T1 are used SR techniques (Saturation Recovery) and IR techniques (Inversion Recovery) usually. To measure of relaxation time T2 can be used SE (Spin Echo) technique. To measure diffusion coefficinets are used PFG-SE and PFG-SSE methods (Pulsed Field Gradient Spin Echo a Pulsed Field Gradient Stimulated Echo) and of course their modification. Experiment itself is described sample preparation of gel electrolytes and to measure their relaxation times.
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