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The beam-type and ion trap collision-induced dissociation (CID) behaviors of protonated bovine ubiquitin ions were studied for charge states ranging from +6 to +12 on a modified triple quadrupole/linear ion trap tandem mass spectrometer. Both beam-type CID and ion trap CID were conducted in a high-pressure linear ion trap, followed by proton-transfer ion/ion reactions to reduce the charge states of product ions mostly to +1. The product ions observed under each activation condition were predominantly b- and y-type ions. Fragmentation patterns showed a much stronger dependence on parent ion charge state with ion trap CID than with beam-type CID using nitrogen as the collision gas, with preferential cleavages C-terminal to aspartic acid at relatively low charge states, nonspecific fragmentation at moderate charge states, and favored cleavages N-terminal to proline residues at high charge states. In the beam-type CID case, extensive cleavage along the protein backbone was noted, which yielded richer sequence information (77% of backbone amide bond cleavages) than did ion trap CID (52% of backbone amide bond cleavages). Collision gas identity and collision energy were also evaluated in terms of their effects on the beam-type CID spectrum. The use of helium as collision gas, as opposed to nitrogen, resulted in CID behavior that was sensitive to changes in collision energy. At low collision energies, the beam-type CID data resembled the ion trap CID data with preferential cleavages predominant, while at high collision energies, nonspecific fragmentation was observed with increased contributions from sequential fragmentation.

A novel molecular framework that differs from proton sponges which could be remotely substituted with different functional groups to tune the geometric and electronic factors to control the basicity of these proton sponges is reported.

The study makes use of a new heteronuclear correlation recoupling technique to observe and investigate the polarization transfer between nuclear species that is mediated by the dipolar couplings and is insensitively assisted by protons. This new technique, proton assisted insensitive nuclei cross polarization reduces dipolar truncation and therefore is particularly well suited for obtaining long distance contacts.

Four membranes containing different equivalent weight (EW) values were examined to clarify the transport mechanisms of alcohols and proton in perfluorosulfonated ionomer (PFSI) membranes for fuel cells. The density functional theory calculations of interactions between proton and alcohols revealed that larger alcohols have larger interaction energies and this relationship explains the proton transport efficiency by the Grotthuss mechanism.

Microstructural changes of NdF[e.sub.10.5]M[o.sub.1.5] and P[r.sub.13]F[e.sub.80][B.sub.7] compounds during the solid-hydrogenation disproportionation recombination process are investigated. It is found that the early disproportionated microstructure of NdF[e.sub.10.5]M[o.sub.1.5] and P[r.sub.13]F[e.sub.80][B.sub.7] alloys show similar rodlike morphology.