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Sirvi Autor "Samuilova, E.O." järgi

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  • Pisipilt
    Kirje
    Influence of the bentonite-containing acrylic humectant composite on the soil microflora
    (2019) Mellelo, E.; Samuilova, E.O.; Denisov, T.S.; Martynova, D.M.; Olekhnovich, R.O.
    Acrylic derivative-based superabsorbents are widely used currently in agriculture as the soil conditioners, plant growth regulators, etc. Their usage has a positive effect on the growth and survival of the plants cultivated in the arid regions. However, the effects of hydrophilic acrylic polymers on the soil microbiocenosis still remain unknown. The influence of the moistureabsorbing acrylic acid-based hydrogels with different proportions of bentonite filler was studied on the soil microbiota. N,N-methylenebisacrylamide was used as a crosslinking agent. Acrylic hydrogels were synthesized by radical polymerization in an aqueous medium at a synthesis temperature of 45 °C during 4 hours. The application of hydrogel of the certain concentrations (1.0, 1.5, and 2.5% wt) into the soil did not cause significant changes in the total abundance of heterotrophic bacteria and the length of the fungal mycelium. The CO2 emission rates did not change after and during the application of the hydrogel), which indicated the same level of carbon mineralization in the soil with presence of acrylic bentonite-containing hydrogels. The nitrogen fixation rate decreased on the first day after hydrogel application; after 14 days, it was close to the control values. We assume the activity of nitrogen-fixing bacteria has though turned to the normal level.
  • Pisipilt
    Kirje
    Tensile properties of wood plastic composites based on plant-filled polyvinyl chloride/poly(3-hydroxybutyrate-co-3- hydroxyhexanoate) matrices
    (2020) Samuilova, E.O.; Podshivalov, A.V.; Fokina, M.I.; Chursina, V.S.; Strelnikova, I.E.; Uspenskaya, M.V.
    The article considers the obtaining and studying of microcomposites based on polyvinyl chloride (PVC)/poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) polymer matrix, filled with a various faction of different natural plant fillers. In work, such plant fillers as wood flour without lignin, spruce flour and rice husk were used. Microcomposites were obtained by melt rolling processing method with subsequent analysis of their morphology and mechanical tensile properties. It is shown that the filler particles were strongly oriented in the direction of the melt rolling process and have a different aspect ratio depending on the filler type. The tensile strength of materials strongly depends on the particle’s aspect ratio. When the aspect ratio of the particles is 4.25, the material has a strength value comparable to a pure PVC/PHBHHx matrix.