Column: BT IV KA column from Biotronik (Germany), pre-column (2x20 mm, grafted C18 phase, 40 μm particle size), and BT-S KG suppression column from Biotronik (Germany).
Mode: Isocratic.
Buffer: Containing 0.002 M HNO3.
Flow Rate: 2.0 ml/min.
Sample Analysis (General):
Column: Resin (2x20 mm pre-column filled with a grafted C18 phase, 40 μm particle size) and a BTS AG suppression column from Biotronik (Germany).
Mode: Isocratic.
Buffer: Carbonate buffer containing 0.002 M Na2CO3 and 0.002 M NaHCO3.
Flow Rate: 2.0 ml/min.
Detection and Calibration
Detection:
UV region at a wavelength of 192 nm using a Star model 9050 photometric detector from Varian (USA).
Conductometric detector (model 550) from Alltech (USA).
Injection: Performed with a microsyringe and an injector with a 100 μl loop.
Calibration: Standard freshly prepared solutions of anions and cations in water, in the concentration range of 0.1 - 10 μg/ml.
Findings on Ions in Swabs
In swabs from objects where TNT and hexogen were detected, ammonium ions and nitrate ions were found in amounts ranging from $10^{-5}$ to $10^{-6}$ g (the largest amount was found in the substance described in item 5).
Nitrate ions and ammonium ions are commonly present in trace amounts in swabs from contact points of any surface with a mixed explosive containing ammonium nitrate.
Substances of organic and inorganic nature are widely used in daily life and the national economy, either containing these ions directly (e.g., ammonium nitrate fertilizers) or forming them during decomposition (e.g., aniline dyes, nitro-lacquers).
It is not possible to unambiguously determine the source of origin of the detected ions based on the results of physicochemical studies.
Aluminum Particle Analysis
Method: SEM-EDXS method was used on a JSM-840 scanning electron microscope from Jeol (Japan) with an ISIS microprobe analyzer from Oxford Instruments (UK).
Conditions: Accelerating voltage of 20 kV.
Detectable Range: Beryllium to uranium.
Results: Deposits on the filters remaining after filtration of swabs from the surface of the cloak (item 2) and the cloth bag (item 1) contained many silver-colored microparticles in the form of flat flakes up to 100 μm in size.
Material: The material of the microparticles was aluminum (no impurities above 0.4% by weight were detected).
Conclusion: In terms of chemical composition, appearance, morphological features, and geometric dimensions, the detected microparticles correspond to domestic aluminum powder (GOST 5494-95).