In traditional scanning electron microscopy/energy dispersive X-ray analysis of gunshot residue (GSR), one has to cope more and more frequently with limitations of this technique due to the use of lead-free ammunition or ammunition lacking heavy metals. New methods for the analysis of the organic components of common propellant powder stabilizers were developed based on liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). A multiple reactions monitoring scanning method was created for the screening of akardite II, ethylcentralite, diphenylamine, methylcentralite, N-nitrosodiphenylamine, 2-nitrodiphenylamine, and 4-nitrodiphenylamine, present in standards mixtures. Five out of seven of these target compounds can be selectively identified and distinguished from the two others with a high accuracy. Samples from the hands of a shooter were collected by swabbing and underwent solid phase extraction prior to analysis. Detection limits ranging from 5 to 115 mug injected were achieved. Results from several firing trials show that the LC-MS/MS method is suitable for the detection of stabilizers in samples collected following the firing of 9 mm Para ammunitions.

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Raman measurements were performed of the lowest rotational J=0 -+2 and the intramolecular vibrational transition of p-H2 confined in a Vycor rod. From the dependence on the amount of H2 adsorbed in the system, we are able to assign specific features in both spectra to molecules which are in contact with the surface.Studies of the temperature dependence show that below 12 K, the system is in a metastable state, which may result in a suddenly freezing in of the molecules, evidenced by a quenching of both transitions. For sufficiently slowly cooled systems, the molecules are able to orient into a phase which is neither hcp nor fcc. Evidence for the occurrence of islands of H2 is provided. For the smaller filling fractions, our results show that a part of the adsorbed molecules may remain in the liquid phase down to lower temperatures than so far observed.