. . "Metal ion as probes for the characterization of geopolymer materials" . . "D\u011Bde\u010Dek, J." . "P(FT-TA4/068)" . . . "1"^^ . . . "Journal of American Ceramic Society" . "Sobal\u00EDk, Z." . . . "[7449BF3D0DFA]" . "1551-2916" . "6"^^ . "Metal ion as probes for the characterization of geopolymer materials"@en . "91(9)" . "geopolymer, metal ions"@en . . "5"^^ . . "RIV/62243136:_____/08:#0000096" . . "Ion exchange of Na+ in geopolymer by Cs+, NH4+ and Co2+ was used to characterize the accessibility of the inner volume of a geopolymer and the size of the rings controlling the mobility of cations in the geopolymer matrix. UV-Vis spectroscopy of Co2+ ions in the Co2+ exchanged samples was used to characterize local structures serving as cationic sites of Co2+ ions in the geopolymer. Na-geopolymer exhibits ion-exchange properties similar to those of zeolites. All Na+ ions could be ion-exchanged by NH4+ or Co2+ ions. This indicates that all the Al atoms are accessible through rings containing at least eight Al and Si atoms. On contrary, Cs+ ion exchange evidence that only one half of the Al atoms are simultaneously accessible through ten- or larger rings. Co2+ ions in the geopolymer network are accommodated in two types of deformed six- or eight-rings. Neither regular six-rings nor the hexagonal prisms are present in the geopolymer network." . "378683" . "Ion exchange of Na+ in geopolymer by Cs+, NH4+ and Co2+ was used to characterize the accessibility of the inner volume of a geopolymer and the size of the rings controlling the mobility of cations in the geopolymer matrix. UV-Vis spectroscopy of Co2+ ions in the Co2+ exchanged samples was used to characterize local structures serving as cationic sites of Co2+ ions in the geopolymer. Na-geopolymer exhibits ion-exchange properties similar to those of zeolites. All Na+ ions could be ion-exchanged by NH4+ or Co2+ ions. This indicates that all the Al atoms are accessible through rings containing at least eight Al and Si atoms. On contrary, Cs+ ion exchange evidence that only one half of the Al atoms are simultaneously accessible through ten- or larger rings. Co2+ ions in the geopolymer network are accommodated in two types of deformed six- or eight-rings. Neither regular six-rings nor the hexagonal prisms are present in the geopolymer network."@en . "2008" . "US - Spojen\u00E9 st\u00E1ty americk\u00E9" . "Tvar\u016F\u017Ekov\u00E1, Z." . "RIV/62243136:_____/08:#0000096!RIV11-MPO-62243136" . . "\u0160ubrt, J." . . "Bortnovsk\u00FD, Oleg" . "Metal ion as probes for the characterization of geopolymer materials"@en . "Metal ion as probes for the characterization of geopolymer materials" .