Close proximity gunshot residues

Intuitively, a hand held in close proximity to a firearm at the instant of discharge will intercept a significant amount of gunshot residue, even though the hand did not actually come into contact with the weapon. There is, however, little information specifically described in the forensic science literature concerning the residue levels which might be encountered in such an instance. The present work confirms that antimony levels consistent with an individual having fired or handled a firearm may be intercepted by a hand held in close proximity.     

Visualization of dyes on thin-layer chromatography plates by means of the argon ion laser

A simple method for the detection of nanogram amounts of dyes by means of their fluorescence in the visible region of the spectrum is described. To stimulate the fluorescence, an argon ion laser with principal lines of 514.5 nm and 488.0 nm is used. The sensitivity of the technique allows the visualization of an amount of dye smaller than could be detected with either visible absorbance or ultraviolet stimulated fluorescence.