One of promising fillers for polymers, sodium montmorillonite modified by dioctadecyldimethylammonium bromide (DODAB), has been studied by Raman spectroscopy, X-ray analysis, and differential scanning calorimetry (DSC). It has been shown that an increase in the DODAB content enlarges the height of a clay interlayer space through filling the clay interlayer galleries with DODAB molecules. According to both Raman and DSC data, DODAB molecules grafted to the clay can be in three different phase states depending on the modifier content. At a low DODAB content, its molecules are separated and contain a significant amount of gauche-conformers in methylene chains. At a medium content, the DODAB molecules form clusters, and the amount of trans-conformers in the DODAB methylene chains considerably increases. At a high DODAB content, its molecules are straightened and form a 2D ordered structure with either hexagonal or triclinic symmetry.Computer-simulated schematic structure of the interlayer space of Na + -montmorillonite modified by DODAB

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We present a new device called <> for monitoring milk parameters and discuss some possibilities of its modification for express-diagnostics of man-caused contamination. At present, the developed laser device <> is capable of precisely measuring the concentration of fats, proteins, and water in milk. The operation of the device is based on comparing the intensities of elastic scauering radiation from three semiconductor lasers with different wavelengths in the near-infrared range. It takes only about 30 seconds to complete a single measurement. Now we are developing a method for express-diagnostics of man-caused toxins (antibiotics, metal salts, etc.) in milk by studying non-elastic scattering and luminescence induced by visible-range laser radiation. The non-elastic scattering radiation in milk contaminated with a salt of lead is studied. It is observed that the radiation intensity decreases with an increase in the impurity concentration. We suppose that this is due to luminescence quenching caused by the impurity presence We have found out that the scattered light intensity exponentially changes with the concentration of the metal. The sensitivity in changing light intensity especially high at low concentrations of impurities.We suppose that these results can be used for express-diagnostics of toxins in milk by the proposed laser device <>.Key words : diagnostic milk composition and salt of metal in milk, scattering light in milk, fat, albumin

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