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The article deals with the concentration changes and relative content of bacterial cells of Desulfuromonas acetoxidans in the intervals of sizes 0.2–2.0 µm under the influence of nano silver particles. Correlation between these changes of light-scattering properties of bacterial cells and growth abilities of bacteria Desulfuromonas acetoxidans under inflence of silver nanoparticles and ions has been shown. The purpose of the work was to research the intensity of processes the change of indexes of the antioxidant system the cells of Desulfuromonas acetoxidans at influence of silver nanoparticles and silver nitrate. The influence of various concentrations of silver nanoparticles and silver nitrate on enzymatic activity of catalase and reduced glutathione synthesis by Desulfuromonas аcetoxidans cells under their cultivation with fumarate addition and with absence of sulphur has been determined. Specific catalase activity increased with enhancing of concentration and duration of bacterial cultivation under the addition of this salt. The highest specific catalase activity was determined on the second day of bacterial growth under the influence of all concentration range of investigated metal salt. The reduced glutathione content under silver nitrate and silver nanoparticles exposure varied depending on the cultivation time and metal concentration. The maximum reduced glutathione content has been observed. The result of catalase activity changes and glutathione content changes of sulfur-reducing D. acetoxidans bacteria cell-free extracts and has been investigated under the influence of different concentrations of Ag nanoparticles during four days of cultivation has been investigated.

The synthesis of finely divided FeVO 4 from aqueous solutions was carried out, iron vanadate particles were incorporated in the polyaniline matrix through the process of oxidative condensation of aniline in a suspension of FeVO 4 in the presence of graphite. In the first case, the content of sulfanilic acid in the initial mixture for the preparation of the composite was 2.0 g, in the second – 1.0 g. The obtained materials on the basis of FeVO 4 are used for making positive electrodes of lithium current sources. Two kinds of lithium batteries were constructed and investigated. The discharge characteristics of the first element are relatively low. This may be due to the relatively higher content of sulfanilic acid on FeVO 4 surface in an electrically active material, which makes it difficult for vanadate particles to participate in the electrochemical process. Probably, sulfanilic acid on FeVO 4 surface can interact with lithium ions with producing insoluble salt. In addition to this case, nitrate and sulfate ions can be ion-dopants of polyaniline. The latter also form with lithium ions insoluble salts in propylene carbonate-ethylene carbonate electrolyte. That leads to the electrode surface blocking and leads to a sharp increase in the internal resistance of element 1. In the case of element 2, a smaller amount of sulfanilic acid was used during the synthesis of the composite. The discharge characteristics of the second element are much higher. There is a small plateau on discharge voltage and current curves. It should be noted that the recharge of element 2 was difficult, as evidenced by small charging currents (1–1.5 mA). That is, the lithium ions slowly diffused from the electrically active material. After reloading the characteristics of element 2 significantly deteriorated. This indicates that not all lithium ions are capable of reversibly intercalating into synthesized electrically active material. Keywords: iron (III) vanadate, lithium power sources, charge-discharge properties.