title: Cross-polarisation method for improvement of 14N NQR signal detectability.
abstract: This is a study of the cross-polarization effects in the case of 14N quadrupolar spin-system with a long spin-lattice relaxation time. Two important benefits of the cross-polarization technique were demonstrated for PETN: (i) a polarization transfer resulting in increased NQR single shot signal response and (ii) a dynamic reduction in recovery time of the NQR system allowing scan repetition on a much shorter timescale. It was proved that this technique can reduce the optimal waiting time between pulse sequences up to 60 times through a significant reduction of the relaxation time of the quadrupolar spin-system. All experiments were carried out at room temperature using spin-locking multi-pulse sequences and small external magnetic field.
authors.affiliation: Research Group, QRSciences Limited, 8-10 Hamilton Street, Cannington, WA 6107, Australia. trudakov@qrsciences.com
authors.forename: T N
authors.initials: TN
authors.lastname: Rudakov
authors.forename: P A
authors.initials: PA
authors.lastname: Hayes
mesh_terms: D000465:Algorithms; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D009584:Nitrogen / Q000032:analysis* / Q000737:chemistry*; D010417:Pentaerythritol Tetranitrate / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013113:Spin Labels
chemical_list: D013113:Spin Labels; D010417:Pentaerythritol Tetranitrate; D009584:Nitrogen