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The bulk magnetization and the (super 1)H and (super 29)Si nuclear-magnetic-resonance (NMR) spectra of two layered silicates, montmorillonite (MMT) and hectrorite (HCT), purified by high-gradient magnetic separation and of HCT-polymer nanocomposites are measured. Magnetically purified hectorite was used for preparing polymer HCT nanocomposites where the NMR spectra show increased signal-to-noise ratios.

The influence of an antimicrobial peptide, protegrin-1 (PG-1) on the curvature and lateral diffusion coefficient (D(sub L)) of phosphocholine bilayers was investigated using one- (1-D) and two-dimensional (2-D) (super 31)P exchange NMR. The simulations of the 2D exchange spectra yielded quantitative reorientation-angle distributions were consistent with the bimodal distributions of the vesicles curvature and the effects of the peptide on the two types of lipid bilayers.

The temperature and magnetic field (H) dependencies of the bulk dc magnetization (M) and the M/H ratio of montmorillonite (MMT), hectorite (HCT) and synthetic mica-montmorillonite (SMMT) clays are measured and compared with the signal intensity of H and Si nuclear magnetic resonance (NMR) spectra. The data highlight that the quality of the NMR spectra is not related to the low-field magnetic susceptibility but to the bulk magnetization in the high magnetic field used for NMR.

A robust method for CH spectral editing is based on dipolar dephasing of heteronuclear multiple quantum coherence. The sequence resembles (distortionless enhancement by polarization transfer (DEPT), although pulse timings are modified to achieve recoupling of CH dipolar interactions.

Researchers at the University of Massachusetts, Amherst, analyze a peat humic acid through two-dimensional solid-state NMR experiments. The article's discussion of the structural information gathered is illustrated by multiple charts and graphs.

New nuclear magnetic resonance (NMR) constraints on the conformation of the headgroup, glycerol backbone, and sn-2 chain of 1,2-dimyristoyl-sn-glycero-3-phophatidylcholine (DMPC) in the liquid-crystalline bilayer are shown. There are significant dipolar couplings between the carboxyl carbon CO2 and the headgroup protons. This suggests that a conformation in which the DMPC headgroup and the beginning of the sn-2 chain bend toward each other is significantly populated in the fluid bilayer.