Elektronų paramagnetinio rezonanso metodo taikymas.
The article describes the results of the original investigations of the gravel mine detection using the modern analysis method - electron paramagnetic resonance (EPR). In the investigation of the criminal offences the problem of the detection of the substances source of different objects is faced. Very often such substances could be an intermediate link between the crime scene investigated and a suspect or some kind of tools, transport means or other objects. The investigations executed broaden the investigation possibilities of gravel (sand) and the similar objects. This could be the basis for a new expertise investigation method and to serve for the forensic geology. The gravel EPR spectrum is modeled using the limestone and dolomite parts mixture. The lines of this spectrum are given by manganese, which got in to the limestone and dolomite grating as a natural impurity in the process of their formation. EPR spectrum depends not only on manganese (as impurity) but also how manganese ions interact with magnesium and calcium. Having admixed gravel with manganese salt a new EPR line is made (wide and in other magnetic field sphere) and former lines, which are given by magnesium being in the gravel do not change. To remove magnesium from the grating is possible only during the chemical reactions. The mathematic methodology is prepared which is suitable to determine from which mine (quarry) the unknown gravel was taken. The methodology is based on the countering of euclid distance between the appropriate EPR spectrum components. For the investigation is enough to have 50-100 mg of the substance (eliminating bigger than 2 mm of diameter parts). [...]
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