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Spray &Trap Method for Analysis of Residual Toxic Agents in Water
Vlčková, Lenka ; Podborský, Vladimír (referee) ; Brno), (VTÚO (advisor)
This work deals with verification of the analysis of precursors or degradation products of toxic compounds in the air and water through GC/MS by method of the thermal desorption or combination of methods "spray & trap" followed by the thermal desorption transfer the sample into the analyzer. Toxic compounds triethyl phosphate (TEP) and diisopropylmethyl phosphonate (DIMP) were choosen for the analysis. For choosen compounds has been optimized desorption time, for TEP 240 seconds and DIMP 210 seconds. Then the calibration curve was made for different concentrations of compounds DIMP and TEP. On the basis of these measurements was tested the possibility of determining the concentration of the compound in water sample using of method "spray & trap“. Thanks to the high solubility of compounds TEP and DIMP in water, higher boiling temperatures in comparison with boiling temperature of water, and extraction at room temperature, it was not possible to detect used compounds. Therefore, the analysis of compounds DIMP and TEP in the water by method "spray & trap“ seems inappropriate.
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The Freezing Point Determination Of Electrolytes With Fire Retardant By Cryoscopy Method
Štulák, Stanislav ; Vondrák, Jiří (referee) ; Máca, Josef (advisor)
The thesis is devoted to the field of properties investigation of new types of electrolytes, and assess the appropriateness of electrolytes studied in this paper for use in Li -ion batteries. It focuses specifically on electrolytes based on aprotic solvents and their mixtures with the flame retardants. The goal of the thesis is to investigate the effects of FRAs on electrolyte mixtures via changes in specific conductivity and freezing point. These objectives were fulfilled by using electrochemical impedance spectroscopy in combination with a cryoscopic measurement method. There were overall 16 samples examined. The samples were prepared as a combination of chemicals, specifically Ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), dimethyl sulfone (DMSO2), triethyl phosphate (TEP) Dimethyl methylphosphonate (DMMP), triphenyl phosphate (TPP). Based on the results of the experiments, the mixtures were sorted according to the observed properties in the tables listed in the last part of this paper. These values can be further used to supplement the continuing research of electrolytes and also as assistance in searching for the new electrolyte mixtures.
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New gel electrolytes
Sumka, Martin ; Jahn, Michal (referee) ; Sedlaříková, Marie (advisor)
This master´s thesis deals with the properties of gel polymer electrolytes, brief characteristics of other types of electrolytes and materials that are used for preparing polymer electrolytes. The thesis explains the use of the gel electrolytes in practice, the current conduction in the electrolytes and the properties of ionic liquids, and flame retardants. This thesis also focuses on methods of measurement of mechanical properties of gel polymer electrolytes. The practical part is focused on preparation of methacrylate gel electrolytes and their modifications with the use of flame retardant - triethyl phosphate (TEP) and ionic liquid - 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (Emim TFSI). In this part there are evaluations of their potential funcionality (potential window) and specific conductance conductivity using the method LSV (linear sweep voltammetry) and impedance spectroscopy. The practical part also includes a thermal analysis of selected samples by TGA, DTA and EGA methods.
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New gel electrolytes
Sumka, Martin ; Jahn, Michal (referee) ; Sedlaříková, Marie (advisor)
This master´s thesis deals with the properties of gel polymer electrolytes, brief characteristics of other types of electrolytes and materials that are used for preparing polymer electrolytes. The thesis explains the use of the gel electrolytes in practice, the current conduction in the electrolytes and the properties of ionic liquids, and flame retardants. This thesis also focuses on methods of measurement of mechanical properties of gel polymer electrolytes. The practical part is focused on preparation of methacrylate gel electrolytes and their modifications with the use of flame retardant - triethyl phosphate (TEP) and ionic liquid - 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (Emim TFSI). In this part there are evaluations of their potential funcionality (potential window) and specific conductance conductivity using the method LSV (linear sweep voltammetry) and impedance spectroscopy. The practical part also includes a thermal analysis of selected samples by TGA, DTA and EGA methods.
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The Freezing Point Determination Of Electrolytes With Fire Retardant By Cryoscopy Method
Štulák, Stanislav ; Vondrák, Jiří (referee) ; Máca, Josef (advisor)
The thesis is devoted to the field of properties investigation of new types of electrolytes, and assess the appropriateness of electrolytes studied in this paper for use in Li -ion batteries. It focuses specifically on electrolytes based on aprotic solvents and their mixtures with the flame retardants. The goal of the thesis is to investigate the effects of FRAs on electrolyte mixtures via changes in specific conductivity and freezing point. These objectives were fulfilled by using electrochemical impedance spectroscopy in combination with a cryoscopic measurement method. There were overall 16 samples examined. The samples were prepared as a combination of chemicals, specifically Ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), dimethyl sulfone (DMSO2), triethyl phosphate (TEP) Dimethyl methylphosphonate (DMMP), triphenyl phosphate (TPP). Based on the results of the experiments, the mixtures were sorted according to the observed properties in the tables listed in the last part of this paper. These values can be further used to supplement the continuing research of electrolytes and also as assistance in searching for the new electrolyte mixtures.
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Spray &Trap Method for Analysis of Residual Toxic Agents in Water
Vlčková, Lenka ; Podborský, Vladimír (referee) ; Brno), (VTÚO (advisor)
This work deals with verification of the analysis of precursors or degradation products of toxic compounds in the air and water through GC/MS by method of the thermal desorption or combination of methods "spray & trap" followed by the thermal desorption transfer the sample into the analyzer. Toxic compounds triethyl phosphate (TEP) and diisopropylmethyl phosphonate (DIMP) were choosen for the analysis. For choosen compounds has been optimized desorption time, for TEP 240 seconds and DIMP 210 seconds. Then the calibration curve was made for different concentrations of compounds DIMP and TEP. On the basis of these measurements was tested the possibility of determining the concentration of the compound in water sample using of method "spray & trap“. Thanks to the high solubility of compounds TEP and DIMP in water, higher boiling temperatures in comparison with boiling temperature of water, and extraction at room temperature, it was not possible to detect used compounds. Therefore, the analysis of compounds DIMP and TEP in the water by method "spray & trap“ seems inappropriate.
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