Cation Separation and Analysis

To separate cations in the mixture under study, a BT IV KA column from Biotronik (Germany) was used, along with a 2x20 mm guard column filled with a grafted C18 phase with a particle size of 40 μm, and a BTS KG suppression column from Biotronik (Germany). Chromatography of the sample was carried out in isocratic mode with a buffer containing 0.002 M HNO₃. Eluent flow rate was 2 ml/min.

Detection of inorganic components was carried out by absorption in the UV region at a wavelength of 192 nm using a Star model 9050 photometric detector from Varian (USA) and a model 550 conductometric detector from Alltech (USA). Injection into the chromatograph was performed using a microsyringe and an injector with a 100 μl loop. Before injecting the test samples, a blank experiment was conducted to check the purity of solvents and glassware. For calibration, standard freshly prepared solutions of ions in water were used in the concentration range of 0.1-10 μg/ml.

As a result, it was established that ammonium ions and nitrate ions are present in the aqueous extracts of washings from all presented samples. Their content in the washings is at a level of about $10^{-2} - 10^{-4}$ g, which exceeds the natural background level (about $10^{-5} - 10^{-7}$ g). Thus, trace amounts of ammonium nitrate are present in the washings from all presented objects.

Particle Analysis

The study of particles with a characteristic metallic luster, found on the objects and present on the surfaces of dried paper filters, was carried out using the SEM-EDX method. During this, the shape and morphology of the particles were studied, and their qualitative elemental composition was determined.

Sample Preparation

Sample preparation for the studies was carried out as follows:

• Filters, samples of powdered substances, and polymer materials were placed in a test tube with alcohol and subjected to ultrasonic treatment to separate particles from the surface of the object and from each other.
• After this, the alcoholic suspension containing microparticles was applied to the surface of the electron microscope stage.
• After the suspension dried, the microparticles were present on the stage surface in the form of a monolayer.
• Particles were collected from the surface of adhesive tapes by wiping with a polymer filter and its subsequent dissolution according to a special procedure.

The studies were carried out on a JSM-840 scanning electron microscope from Jeol (Japan) with an ISIS X-ray spectral microprobe analyzer from Oxford Instruments (UK) according to standard methods. Accelerating voltage - 20 kV. Determined elements - from beryllium to uranium.

As a result, it was established that the silver-grey particles with a characteristic metallic luster found on the objects listed in points 3.1, 4.1 – 4.5, 5.1, are metallic aluminum in