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Lithium Phosphate Glasses stabilized with Tungsten Oxide
Míka, M. ; Mladonický, P. ; Vondrák, Jiří ; Stopka, Pavel ; Klápště, Břetislav
Glass exhibiting an increased ionic conductivity could be an attractive material for the construction of electrochemical solid-state devices such as ion-selective sensors, batteries, fuel cells, and electrochromic devices. In these devices the glass can function as a membrane, solid electrolyte or electrode if shows mixed electric conductivity. Amorphous nature gives glass considerable advantages comparing to polycrystalline materials.If we use chemical composition systems with a good glass-forming ability, we can add many different cations and this way "tune" glass properties. Because a large portion of glass volume is occupied by oxygen atoms, many glass properties are strongly influenced by the state of oxygen atoms, especially by the the electron density. God glass-forming ability is exhibited for example by alkali-phosphate glass.
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EPR study of beer samples and brewing materials
Stopka, Pavel
Hydroxyl (OH.), nitroxide (NO.)and stable organic free radicals were identified and determined in samples of beer. The maximum of their concentration is 5-10 min. after the opening of bottle. The influence of UV irradiation and hydrogen peroxide is de
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