Physicochemical Properties of Pure Water Treated by Pure Argon Plasma Jet Generated by Microwave Discharge in Opened Atmosphere

Abstract

The physicochemical properties of water activated by high-purity low-temperature argon plasma of electrodeless microwave discharge at atmospheric pressure are investigated. Such parameters of activated water as electrical conductivity, redox potential, hydrogen index (pH), the concentrations of dissolved molecular oxygen, hydrogen peroxide, OH-radicals, nitrate and nitrite anions depending on the plasma jet distance above the water surface and duration of activation were studied. Under irradiation conditions close to optimum, it was shown that the generation rate in the absence of impurities are 200 μM/min for H2O2; 800 μM/min for •OH and 2 mM/min for NOx−. The use of plasma activated water (PAW) in agriculture has been tested. It was shown that strawberry seeds treated with a surfactant solution grow much faster than control seeds. The mechanisms of the chemical composition formation of activated water and its biological properties are discussed.

Enhancement of the Plant Grafting Technique with Dielectric Barrier Discharge Cold Atmospheric Plasma and Plasma-Treated Solution

“…The content of nitrite and nitrate anions in the samples was determined using the Griss reagent according to the method described previously [ 37 , 65 ] using a Multiscan FC plate reader (TermoScintific, Vaanta, Finland), and the optical density of the medium was measured at a wavelength of 546 nm. Sodium nitrite and sodium nitrate solutions of known concentration were used for calibration.…”

Enhancement of Wheat Seed Germination, Seedling Growth and Nutritional Properties of Wheat Plantlet Juice by Plasma Activated Water

“…In the meantime, our results showed that the formation of NO 2 − and NO 3 − resulted in reduced pH and increased EC, which was consistent with other studies. For example, Sergeichev et al ( 2021 ) investigated the physicochemical properties of pure water treated by an Ar microwave plasma jet and showed that EC values and NO 2 − and NO 3 − concentrations increased linearly with plasma exposure times. Similarly, Zhou et al ( 2019 ) showed the same change tendency with lower pH and higher RONS in PAW treated with N 2 , He, Air and O 2 plasma.…”

Increase of Productivity and Neutralization of Pathological Processes in Plants of Grain and Fruit Crops with the Help of Aqueous Solutions Activated by Plasma of High-Frequency Glow Discharge

“…The content of nitrate anions in the samples was determined using the Griss reagent according to the method described earlier [ 12 ]. To determine the concentrations of nitrate anions, the test solutions in a volume of 100 μL were applied to the wells of a 96-well flat-bottom polystyrene plate.…”

“…Usually, to obtain activated aqueous solutions, devices are used, the principle of operation of which is based on electrochemical methods using electrolyzers of various designs, including the separation of water into the constituents “anolyte” and “catholyte” [ 7 , 8 ]. In recent years, a method for activating water, as well as an aqueous solution of various electrolytes, has become widespread by exposing its surface to a low-temperature non-equilibrium plasma generated by a high-voltage electric discharge in an atmosphere of various gases [ 9 , 10 ], a microwave discharge in an argon atmosphere [ 11 , 12 ], high-voltage discharge in the volume of water under conditions of intense cavitation [ 13 , 14 ].…”