Accession Number:

AD0722232

Title:

Nuclear Magnetic Resonance Studies of Molecular Interactions at Phase Interfaces,

Descriptive Note:

Corporate Author:

ARMY MOBILITY EQUIPMENT RESEARCH AND DEVELOPMENT CENTER FORT BELVOIR VA

Personal Author(s):

Report Date:

1971-03-01

Pagination or Media Count:

17.0

Abstract:

The high-resolution NMR spectra of water adsorbed on pyrogenic alumina, silica and titania were taken at coverages of approximately 2 to 16 layers. The water line widths were 280 to 300 Hz on alumina, 60 to 80 Hz on silica, and 50 to 110 Hz on titania. The chemical shift of water adsorbed on alumina and silica was relatively constant as a function of coverage, while the water line on titania shifted 0.4 ppm downfield as the coverage decreased from 16.1 to 2.3 layers. Because the NMR spectra of liquids adsorbed on solids are complicated by inhomogeneous broadening and chemical exchange, it was concluded that NMR line widths and chemical shifts are not related to the molecular interactions in any simple fashion. For this reason, NMR spectroscopy is not recommended as a reliable method of selecting solid media to improve coalescence of emulsions. Author

Subject Categories:

  • Physical Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE