PROSPECTIVES AND LIMITATIONS OF NQR SIGNALENHANCEMENT BY POLARISATION TRANSFER

摘要

In this contribution we discuss the prospectives and limitationsof enhanced '4N NQR of nitrogen containing compounds. Our consider-ations are exemplified by Nuclear Magnetic Resonance (NMR) and NQRfield cycling experiments on two systems, namely TNT and urea. It turnsout that the optimum signal-to-noise ratio depends in a subtle way on the spin-lattice relaxation rates of the involved spins, T,-'('H) and aswell as on the polarization transfer rate R(' H, 14N) between the proton andthe nitrogen nuclear spin reservoirs.