Matches in SemOpenAlex for { <https://semopenalex.org/work/W1502489076> ?p ?o ?g. }
Showing items 1 to 74 of
74
with 100 items per page.
- W1502489076 endingPage "1213" @default.
- W1502489076 startingPage "1212" @default.
- W1502489076 abstract "Abstract Hydrothermally treated zeolites H-Y were investigated by XRD, 29Si MAS NMR, 27A1 MQMAS NMR, high-field 27A1 MAS NMR, and 1H MAS NMR spectroscopy. Upon adsorption of ammonia on the hydrothermally treated materials, a reversible change of octahedrally coordinated to tetrahedrally coordinated aluminum atoms was found. Quantitative 29Si, 27A1, and 1H MAS NMR measurements indicated that this coordination change is accompanied by the formation of bridging OH groups (SiOHAl) in the dehydrated materials, while only a weak decrease in the amount of silanol (SiOH) groups and no systematic change of A10H groups occurred. Based on these results, a model for the reversible coordination change of aluminum atoms in the framework of hydrothermally treated zeolites H-Y is proposed assuming local structures consisting of threefold-coordinated framework aluminum atoms with SiO− defect sites in their vicinity, which are coordinated to extra-framework aluminum species. After adsorption of ammonia at the threefold-coordinated framework aluminum atoms, the SiO− defect sites are healed to Si-O-Al− bridges leading to a transformation of the threefold-coordinated aluminum atoms to tetrahedrally coordinated atoms. Upon thermal decomposition of the ammonium ions formed at these Si-O-Al− bridges, SiOHAl groups occur." @default.
- W1502489076 created "2016-06-24" @default.
- W1502489076 creator A5005952304 @default.
- W1502489076 creator A5036339848 @default.
- W1502489076 creator A5057412064 @default.
- W1502489076 creator A5062680140 @default.
- W1502489076 creator A5088868749 @default.
- W1502489076 date "2004-01-01" @default.
- W1502489076 modified "2023-09-26" @default.
- W1502489076 title "Elucidating the dealumination mechanism of zeolite H-Y by solid-state NMR spectroscopy" @default.
- W1502489076 cites W2019207244 @default.
- W1502489076 cites W2074638100 @default.
- W1502489076 doi "https://doi.org/10.1016/s0167-2991(04)80630-x" @default.
- W1502489076 hasPublicationYear "2004" @default.
- W1502489076 type Work @default.
- W1502489076 sameAs 1502489076 @default.
- W1502489076 citedByCount "9" @default.
- W1502489076 countsByYear W15024890762012 @default.
- W1502489076 countsByYear W15024890762017 @default.
- W1502489076 countsByYear W15024890762019 @default.
- W1502489076 countsByYear W15024890762022 @default.
- W1502489076 crossrefType "book-chapter" @default.
- W1502489076 hasAuthorship W1502489076A5005952304 @default.
- W1502489076 hasAuthorship W1502489076A5036339848 @default.
- W1502489076 hasAuthorship W1502489076A5057412064 @default.
- W1502489076 hasAuthorship W1502489076A5062680140 @default.
- W1502489076 hasAuthorship W1502489076A5088868749 @default.
- W1502489076 hasConcept C107814960 @default.
- W1502489076 hasConcept C121332964 @default.
- W1502489076 hasConcept C147789679 @default.
- W1502489076 hasConcept C153202636 @default.
- W1502489076 hasConcept C161790260 @default.
- W1502489076 hasConcept C178790620 @default.
- W1502489076 hasConcept C185592680 @default.
- W1502489076 hasConcept C192562407 @default.
- W1502489076 hasConcept C2778077586 @default.
- W1502489076 hasConcept C32891209 @default.
- W1502489076 hasConcept C46141821 @default.
- W1502489076 hasConcept C62520636 @default.
- W1502489076 hasConcept C8010536 @default.
- W1502489076 hasConcept C89611455 @default.
- W1502489076 hasConceptScore W1502489076C107814960 @default.
- W1502489076 hasConceptScore W1502489076C121332964 @default.
- W1502489076 hasConceptScore W1502489076C147789679 @default.
- W1502489076 hasConceptScore W1502489076C153202636 @default.
- W1502489076 hasConceptScore W1502489076C161790260 @default.
- W1502489076 hasConceptScore W1502489076C178790620 @default.
- W1502489076 hasConceptScore W1502489076C185592680 @default.
- W1502489076 hasConceptScore W1502489076C192562407 @default.
- W1502489076 hasConceptScore W1502489076C2778077586 @default.
- W1502489076 hasConceptScore W1502489076C32891209 @default.
- W1502489076 hasConceptScore W1502489076C46141821 @default.
- W1502489076 hasConceptScore W1502489076C62520636 @default.
- W1502489076 hasConceptScore W1502489076C8010536 @default.
- W1502489076 hasConceptScore W1502489076C89611455 @default.
- W1502489076 hasLocation W15024890761 @default.
- W1502489076 hasOpenAccess W1502489076 @default.
- W1502489076 hasPrimaryLocation W15024890761 @default.
- W1502489076 hasRelatedWork W1591994152 @default.
- W1502489076 hasRelatedWork W2011156626 @default.
- W1502489076 hasRelatedWork W2056355288 @default.
- W1502489076 hasRelatedWork W2078595924 @default.
- W1502489076 hasRelatedWork W2094387008 @default.
- W1502489076 hasRelatedWork W2402061725 @default.
- W1502489076 hasRelatedWork W2737421493 @default.
- W1502489076 hasRelatedWork W3007294050 @default.
- W1502489076 hasRelatedWork W3145997160 @default.
- W1502489076 hasRelatedWork W4229500127 @default.
- W1502489076 isParatext "false" @default.
- W1502489076 isRetracted "false" @default.
- W1502489076 magId "1502489076" @default.
- W1502489076 workType "book-chapter" @default.