| Popis: |
In this report, experimental methods and calculation procedures are described for direct and simultaneous quantification of the Bronsted- and Lewis-acid site concentrations in a sample of USY zeolite. The concentrations of both types of acid sites are characterized by solid-state 31 P MAS NMR spectroscopy of trimethylphosphine oxide probe molecules. The errors associated with the area measurements in the NMR spectrum, and hence the errors in the concentration measurements reported, are estimated with Monte Carlo simulations applied with spectral line-fitting and deconvolution procedures. |
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