The rapid identification for drugs-of-abuse in airports is of critical importance. In this study we demonstrate the viability of Raman spectroscopy for the rapid identification of illicit substances in their containers in an airport environment.Raman spectra of drugs-of-abuse in situ were collected using portable Raman spectrometers; this technique offers distinct advantages to government agencies, first responders and forensic scientists working in the security field. We have demonstrated that the spectrometers are able to collect the spectra of suspect powders, including cocaine HCl and d-amphetamine sulphate with unknown constituents rapidly and with a high degree of discrimination.

The nuclear magnetic resonance of 23Na in powder samples of hydrous and anhydrous sodium molybdate and sodium tungstate has been investigated. The anhydrous compounds crystallize in the cubic spinel of type H11, Fd3m presumably with ionic charges of 1 + and 6 + on the metals. The 23Na quadrupole couplings are the largest yet observed for this nucleus and have values of 2.62 and 2.48 MHz in the molybdate and tungstate respectively, as determined from both first- and second-order effects on the magnetic resonance spectrum. These couplings have negligible temperature dependences. Using charges of 1 + and 6 + for the metal ions, assuming that the oxygens are in their ideal positions in the spinel structure and neglecting any contributions from oxygen dipoles and quadrupoles, the electric field gradient was calculated to be 12 × 1013 e.s.u./cm3, in good agreement with the experimental gradient of 7.5 × 1013 e.s.u./cm3. Preliminary measurements of the sodium spin–lattice relaxation time, using tone-burst techniques, indicated a value between 30–60 s. The 95.97Mo nuclear resonances were also observed in the molybdate and these resonances showed no quadrupole effects.

Paramagnetic vanadium-phosphate and molybdenum-phosphate glasses have been studied using electron-spin resonance and nuclear magnetic resonance. These glasses were nominally 80% MO:20% P2O5, where MO denotes the transition-metal oxide. The electron-spin-resonance results showed a strongly exchanged, narrowed interaction with V4+/V5+ and Mo5+/Mo6+ ratios and line shapes which were independent of temperature over the range 77°–300°K. Since the conductivity is nonlinear in this temperature range, the result is direct evidence that the mobility is temperature dependent and that the average paramagnetic-site is unchanged over this temperature range. The nuclear magnetic resonance of 51V and 31P in the glasses verifies the assumption of exchange narrowing. The 51V quadrupole coupling (1.5 MHz) and spin-lattice relaxation time (T1<500 μsec) were temperature independent over the 77°–300°K range. The 31P resonances in each of the glasses also had temperature-independent properties. For the molybdenum glass the linewidth was 0.45 G and T1=300 msec. For the vanadium glass the corresponding numbers were 1.4 G and <500 μsec. The results are compared in part with previously published values.

No abstract

No abstract