Проявление линии Видома при микроволновых измерениях увлажненных перекисью водорода сорбентов

For deeply supercooled bulk water, anomalies of thermodynamic values are known near the Widom line, the locus of increased fluctuations of entropy and density. In this work, we measured the reflected power of microwave radiation at a frequency of 18 GHz from a silicate sorbent sample moistened with a hydrogen peroxide solution. In the experiment, we observed variations in the recorded reflected radiation power in the range –46 – –47 °С, determined by structural changes in the liquid. Thus, it is shown that fluctuations of water parameters near the Widom line are manifested in changes not only in thermodynamic, but also in electrophysical quantities.

Inactivation of SARS-CoV-2 and influenza A virus by spraying hypochlorous acid solution and hydrogen peroxide solution in the form of Dry Fog

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), is transmitted by droplet and contact infection. SARS-CoV-2 that adheres to environmental surfaces remains infectious for several days. We herein attempted to inactivate SARS-CoV-2 and influenza A virus adhering to an environmental surface by spraying aerosolized hypochlorous acid solution and hydrogen peroxide solution in the form of Dry Fog (fog that does not wet objects even if touched). SARS-CoV-2 and influenza virus were dried on plastic plates and placed into a test chamber for inactivation by the Dry Fog spraying of disinfectants. The results obtained showed that Dry Fog spraying inactivated SARS-CoV-2 and influenza A virus in time- and exposed disinfectant amount-dependent manners. SARS-CoV-2 was more resistant to the virucidal effects of aerosolized hypochlorous acid solution and hydrogen peroxide solution than influenza A virus; therefore, higher concentrations of spray solutions were required to inactivate SARS-CoV-2 than influenza A virus. The present results provide important information for the development of a strategy that inactivates SARS-CoV-2 and influenza A virus on environmental surfaces by spatial spraying.

Synthesis and properties of composite material "Mo2C — carbon fiber"

Molybdenum semicarbide Mo2C was synthesized on carbon fibers Carbopon-B-22 by the method of currentless transfer in molten NaCl-KCl-Na2MoO4-Mo salts. The electrocatalytic activity of the Mo2C/C composite material in a hydrogen peroxide solution has been investigated. It was revealed that this composite material is catalytically inactive in an H2O2 solution. The electrocatalytic activity of composite materials Mo2C/C, TaC/C, NbC/C and uncoated carbon fiber in the decomposition of hydrogen peroxide is compared. The method of cyclic voltammetry confirmed the low activity of Mo2C/C in comparison with other composites.

Morphophysiological Changes in Staphylococcus aureus Biofilms Treated with Plasma-Activated Hydrogen Peroxide Solution

Plasma-activated solution has attracted more attention in the food industry due to no chemical residue and good bacteriostatic properties. This study aimed to evaluate the effects of plasma-activated hydrogen peroxide solution (PAH) on the morphophysiology of Staphylococcus aureus biofilms. PAH was prepared using dielectric-barrier-discharge plasma and incubated with S. aureus biofilms for 0–40 min. Changes in biofilm morphophysiology were evaluated with laser scanning confocal microscopy, electron microscopic images, reactive oxygen species (ROS) content, metabolic capacity, and 1% agarose gel. Results indicated that the population of S. aureus in the biofilms was reduced by 4.04-log after incubation with PAH for 30 min. The thickness and metabolic capacity of biofilms were decreased, the ROS content and DNA fragments of bacteria increased after PAH treatments. Data suggested that PAH treatments significantly destroyed the morphophysiology of S. aureus (ATCC 6538) biofilms and could be considered as a valuable anti-biofilm technology to reduce foodborne pathogens on food and/or in food facilities.

Heterogeneous Fenton-Like Oxidation of Methylene Blue Using Alternative Catalysts

The usage of the low-cost catalysts for methylene blue removal from wastewater was investigated. Heterogeneous Fenton-like process consists of the use of a hydrogen peroxide solution, and an iron-rich catalyst, red mud and black nickel mud were used for that purpose. The factors such as the catalyst dose and the hydrogen peroxide solution volume were monitored. The results of experiments showed that the degradation of methylene blue dye in Fenton-like oxidation process using selected catalysts can be described by a pseudo-second-order kinetic model. The highest dye removal efficiency (87.15 %) was achieved using the black nickel mud catalyst after 30 minutes of reaction.

Effects of Neonatal Oxidative Stress on the Social Affinity and Survival in Larval Zebrafish (Danio rerio)

Background Exposure to oxidative stress (OS) incurs various consequences in animals’ life from molecular to organismic level. Survival and social affinity are the two representative fitness components of animals that can be impacted by early exposure to OS during the developmental process. However, the effect of early OS exposure on survival and social affinity has not been well addressed. Results In this study, we treated 0, 1, and 5 mM of hydrogen peroxide solution to four-days post fertilization (dpf) larval zebrafish (Danio rerio) for 30 mins, and examined their survival until 19 dpf and social affinity at 28 dpf. There were no significant differences in survival among the treatment groups. On the other hand, social affinity was reduced in the individuals exposed to 5 mM hydrogen peroxide solution. All the groups demonstrated a similar level of locomotion. Conclusions These findings indicate that mild neonatal OS exposure did not affect the survival but partially hampered social affinity. Whether and how partially hampered social affinity in larval zebrafish persists to adulthood need to be investigated.