Репозиторий Университета

© 2020 Elsevier B.V. Over the last two decades, the scientific community and industry have made huge efforts to develop environmental protection technologies. In particular, the scarcity of drinking water has prompted the investigation of several physico-chemical treatments, and synergistic effects have been observed in hyphenated techniques. Herein, we report the first example of water treatment under simultaneous hydrodynamic cavitation and plasma discharge with the intense generation of radicals, UV light, shock waves and charged particles. This highly reactive environment is well suited to the bulk treatment of polluted water (i.e. E. coli disinfection and organic pollutant degradation). We have developed a new prototype and have efficiently applied this hybrid technology to water disinfection and the complete degradation of methanol in water with the aim of demonstrating its scalability. We have analyzed the mechanisms of water disinfection under the abovementioned conditions and verified them by measuring cavitation noise spectra and plasma emission spectra. We have also used the degradation of textile dyes and methanol solutions as an indicator for the formation of radicals.

© 2020 Elsevier B.V. Over the last two decades, the scientific community and industry have made huge efforts to develop environmental protection technologies. In particular, the scarcity of drinking water has prompted the investigation of several physico-chemical treatments, and synergistic effects have been observed in hyphenated techniques. Herein, we report the first example of water treatment under simultaneous hydrodynamic cavitation and plasma discharge with the intense generation of radicals, UV light, shock waves and charged particles. This highly reactive environment is well suited to the bulk treatment of polluted water (i.e. E. coli disinfection and organic pollutant degradation). We have developed a new prototype and have efficiently applied this hybrid technology to water disinfection and the complete degradation of methanol in water with the aim of demonstrating its scalability. We have analyzed the mechanisms of water disinfection under the abovementioned conditions and verified them by measuring cavitation noise spectra and plasma emission spectra. We have also used the degradation of textile dyes and methanol solutions as an indicator for the formation of radicals.

© 2020 Elsevier B.V. Over the last two decades, the scientific community and industry have made huge efforts to develop environmental protection technologies. In particular, the scarcity of drinking water has prompted the investigation of several physico-chemical treatments, and synergistic effects have been observed in hyphenated techniques. Herein, we report the first example of water treatment under simultaneous hydrodynamic cavitation and plasma discharge with the intense generation of radicals, UV light, shock waves and charged particles. This highly reactive environment is well suited to the bulk treatment of polluted water (i.e. E. coli disinfection and organic pollutant degradation). We have developed a new prototype and have efficiently applied this hybrid technology to water disinfection and the complete degradation of methanol in water with the aim of demonstrating its scalability. We have analyzed the mechanisms of water disinfection under the abovementioned conditions and verified them by measuring cavitation noise spectra and plasma emission spectra. We have also used the degradation of textile dyes and methanol solutions as an indicator for the formation of radicals.

The aim of the study was to assess the possibility of penetration of Escherichia coli bacteria into the dentinal tubules of the samples and determine the antimicrobial efficacy after 5 and 20 min exposition of 3% H2O2 (groups I and II) and 1 and 5 min exposition of 3% NaOCl (groups III and IV) for surface disinfection of bovine teeth. The samples were subjected to inoculation with E. coli suspension. The quality of disinfection was assessed with the three methods. The surface disinfection of samples proved to be effective only in groups II and IV. In the cultures of all dissolutions of dentinal chips suspensions in groups I, III and V there was a growth of E. coli in the form of a continuous pitch. In the group II a growth of Escherichia coli was revealed only in the initial dissolution in the quantity 1,8x101 CFU/ml, whereas in the group IV the growth was nil. Quantitative estimation of bacterial penetration using the method of maximum dissolutions revealed similar quantity of bacteria as in the group II as well as in the calculation of CFU. The application of 3% solution of H2O2 with the exposition of 20 minutes secures the qualitative surface disinfection of teeth without destruction of bacteria inside dental tubules and that allows to discover viable bacteria inside dentinal tubules.

© 2018 Techno-Press, Ltd. In order to prevent the phenomena of "microbiological genocide", unjustified and unfavorable violations in microecological systems, and, first of all, human microbiota during the implementation of the disinfection prevention of diseases, the necessity for the scientific justification and practical provision of sufficient antimicrobial selectivity of disinfecting effects, is substantiated in the article. It is necessary to decode and take into account the susceptibility of different microbe pathogens to various disinfectants in comparison with saprophyte, and even more so, useful microflora.