Chemical shift calibration of 1H MAS NMR liver tissue spectra exemplified using a study of glycine protection of galactosamine toxicity

2009 ◽  
Vol 47 (S1) ◽  
pp. S47-S53 ◽  
Author(s):  
Young-Shick Hong ◽  
Muireann Coen ◽  
Cynthia M. Rhode ◽  
Michael D. Reily ◽  
Donald G. Robertson ◽  
...  
Keyword(s):  
Chemical Shift ◽  
Liver Tissue ◽  
Mas Nmr ◽  
1H Mas Nmr

Identification of the OH groups responsible for kinetic basicity on MgO surfaces by 1H MAS NMR

2009 ◽  
Vol 268 (1) ◽  
pp. 175-179 ◽  
Author(s):  
Céline Chizallet ◽  
Hugo Petitjean ◽  
Guylène Costentin ◽  
Hélène Lauron-Pernot ◽  
Jocelyne Maquet ◽  
...  
Keyword(s):  
Mas Nmr ◽  
1H Mas Nmr ◽  
Oh Groups

1H mas NMR and IR studies of the acidic properties of realuminated zeolite Y

1989 ◽  
Vol 3 (3) ◽  
pp. 263-272 ◽  
Author(s):  
Jacek Klinowski ◽  
Halimaton Hamdan ◽  
Avelino Corma ◽  
Vincente Forn�s ◽  
Michael Hunger ◽  
...  
Keyword(s):  
Zeolite Y ◽  
Mas Nmr ◽  
Acidic Properties ◽  
1H Mas Nmr ◽  
Ir Studies

Aluminum Siting in the ZSM-22 and Theta-1 Zeolites Revisited: A QM/MM Study

2008 ◽  
Vol 73 (6-7) ◽  
pp. 909-920 ◽  
Author(s):  
Stepan Sklenak ◽  
Jiří Dědeček ◽  
Chengbin Li ◽  
Fei Gao ◽  
Bavornpon Jansang ◽  
...  
Keyword(s):  
Experimental Data ◽  
Chemical Shift ◽  
Nearest Neighbor ◽  
Membered Ring ◽  
Mas Nmr ◽  
Isotropic Chemical Shift ◽  
Reaction Space ◽  
Ring Channel ◽  
T1 And T2 ◽  
Nmr Signals

The Al siting in the silicon rich ZSM-22 and Theta-1 zeolites of the TON structure was investigated analyzing already published 27Al 3Q MAS NMR experimental data using QM/MM calculations. The results of our computations show that Al atoms can be located in 6 framework T positions because the two eightfold sites (T1 and T2) split into four fourfold T sites after an Al/Si substitution. The observed resonance at 55.5 ppm corresponds to the T4 site which is predominantly occupied by Al. This site is not located on the surface of the TON ten-membered ring channel and thus the protonic sites related with the majority of Al atoms in the TON structure exhibit a significantly limited reaction space. The 27Al NMR signals centered at 57.6 and 58.7 ppm correspond to either the T2 and T3 sites, respectively, or only to T2. The T2 and T3 sites accommodate some 40% and up to 10%, respectively, of Al while the T1 site is unoccupied by Al. Isotropic shifts of 61.1 and 61.6 ppm were calculated for Al atoms located in the T1-1 and T1-2 sites, respectively. The effect of a silanol "nest" as a next-next-nearest neighbor on the 27Al isotropic chemical shift of Al located in the T4 site is calculated to be less than 1 ppm.

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