INFLUENCE OF L. PARACASEI SPP. PARACASEI BN ATC 8W ON THE GROWTH OF E. СOLI IN SKIMMED MILK

The bacteriocinogenic strain Lactobacillus paracasei spp. paracasei BN ATC 8w was isolated from traditional «Motal» cheese and has strong antimicrobial activity against some Gram-positive and Gram-negative bacteria. The in situ activity of the strain was studied in skimmed milk against E. coli ATCC 25922 for 24 hours. Cooperative cultivation of the active strain L. paracasei spp. paracasei BN ATC 8w with E. coli ATCC 25922 сells in skimmed milk at a concentration of OD 0.28 after 24 hours (300C) led to a decrease up to almost 50% of the concentration of E. coli, which was found in the absence of an active strain in the medium. This indicates the in situ efficiency of the L. paracasei spp. paracasei BN ATC 8w in skim milk for the biological protection of dairy products from opportunistic pathogens

Enhanced Dielectric Constant for Efficient Electromagnetic Shielding Based on Carbon-Nanotube-Added Styrene Acrylic Emulsion Based Composite

An efficient electromagnetic shielding composite based on multiwalled carbon nanotubes (MWCNTs)-filled styrene acrylic emulsion-based polymer has been prepared in a water-based system. The MWCNTs were demonstrated to have an effect on the dielectric constants, which effectively enhance electromagnetic shielding efficiency (SE) of the composites. A low conductivity threshold of 0.23 wt% can be obtained. An EMI SE of ~28 dB was achieved for 20 wt% MWCNTs. The AC conductivity (σac) of the composites, deduced from imaginary permittivity, was used to estimate the SE of the composites in X band (8.2–12.4 GHz), showing a good agreement with the measured results