DC Field | Value | Language |
---|---|---|
dc.contributor.advisor | Ryoo, Ryong | - |
dc.contributor.advisor | 유룡 | - |
dc.contributor.author | Kwak, Ja-Hun | - |
dc.contributor.author | 곽자훈 | - |
dc.date.accessioned | 2011-12-13T04:59:08Z | - |
dc.date.available | 2011-12-13T04:59:08Z | - |
dc.date.issued | 1993 | - |
dc.identifier.uri | http://library.kaist.ac.kr/search/detail/view.do?bibCtrlNo=68347&flag=dissertation | - |
dc.identifier.uri | http://hdl.handle.net/10203/32617 | - |
dc.description | 학위논문(석사) - 한국과학기술원 : 화학과, 1993.2, [ vi, 45 p. ] | - |
dc.description.abstract | $^{129}Xe$ NMR and xenon adsorption methods have been used for characterization of NaX zeolite exchanged with $Cu^{2+}$ ion. The chemical shift in $^{129}Xe$ NMR spectrum for the adsorbed xenon appeared to decrease gradually as the ion exchange level of $Cu^{2+}$ was increased, without a significant change in the pressure dependence. This result suggests that the copper ion was located in a site which was inaccessible for xenon collision. Due to a paramagnetic center at the $Cu^{2+}$ ion, the $^{129}Xe$ NMR line width was increased with the Cu loading. Because of two $Na^+$ ions became to substitute for one copper ion, the adsorbed xenon quantity seemed to decrease linearly with increasing the copper ion exchange level. Magic angle spinning (MAS) solid state $^{29}Si$ NMR has also been used for investigation of $Cu^{2+}$ ion exchange site in faujasitetype zeolites. When the $Cu^{2+}$ ion was exchanged as aqueous complex, the paramagnetic $Cu^{2+}$ ion locally affected the line width in the $^{29}Si$ MAS NMR spectrum. This line broadening was very selective and characteristic of the ion exchange level. The site preference for $Cu^{2+}$ ion was $Si(-OAl)_4 > Si(-OAl)_3 > Si(OAl)_2$ etc. On the contrary, if $Cu^{2+}$ ion was exchanged as ammine form, the line width variation was not selective. The result was due to the ion exchange of $Cu(H_2O)^{2+}_4$ at a site which was composed of two $AlO_4$ tetrahedra bridged by a Si atom, and therefore the paramagnetic effect was concentrated at the silicon atom. However, the ammine form seemed to lose the selectivity because it was exchanged as an octahedral complex. | eng |
dc.language | eng | - |
dc.publisher | 한국과학기술원 | - |
dc.title | Solid state NMR study of $Cu^2+$ exchange on faujasite-type zeolites | - |
dc.title.alternative | NMR을 이용한 구리 이온 교환된 제올라이트의 특성 연구 | - |
dc.type | Thesis(Master) | - |
dc.identifier.CNRN | 68347/325007 | - |
dc.description.department | 한국과학기술원 : 화학과, | - |
dc.identifier.uid | 000911027 | - |
dc.contributor.localauthor | Ryoo, Ryong | - |
dc.contributor.localauthor | 유룡 | - |
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