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We present novel means to hyperpolarize deuterium nuclei in 13CD2 groups at cryogenic temperatures. The method is based on cross-polarization from 1H to 13C and does not require any radio-frequency fields applied to the deuterium nuclei. After rapid dissolution, a new class of longlived spin states can be detected indirectly by 13C NMR in solution. These long-lived states result from a sextet-triplet imbalance (STI) that involves the two equivalent deuterons with spin I = 1. An STI has similar properties as a triplet-singlet imbalance that can occur in systems with two equivalent I = 1=2 spins. Although the lifetimes TSTI are shorter than T1(Cz), they can exceed the life-time T1(Dz) of deuterium Zeeman magnetization by a factor of more than 20. [ABSTRACT FROM AUTHOR]

We discuss from the perspective of relaxation dynamics the feasibility of recording NMR spectra of 33S nuclei bound to cross-link junctions in cross-linked elastomers (i.e. vulcanized rubber). Assuming the quadrupolar relaxation mechanism due to fluctuating electric field gradients, the calculations of transverse and longitudinal 33S relaxation times encompassing a large range of correlation times, static magnetic fields, and quadrupolar coupling constants reveal that both relaxation processes will constitute significant bottlenecks in recording the 33S spectra of cross-linked elastomers inherently endowed with a large distribution of motional modes. In the rubbery state, the observable 33S NMR signal will result from motionally averaged, central transition magnetization of the 33S nuclei in cross-link junctions involved in large amplitude, high-frequency motions. [ABSTRACT FROM AUTHOR]

Based on Redfield's theory of nuclear magnetic relaxation, a computer package capable of computing longitudinal and transverse relaxation rates and amplitudes as well as dynamic frequency shift for all quadrupolar nuclei (all integer spin numbers from 1 to 6 and all half-integer spin numbers from [ABSTRACT FROM AUTHOR]