Self-oscillating Water Chemiluminescence Modes and Reactive Oxygen Species Generation Induced by Laser Irradiation; Effect of the Exclusion Zone Created by Nafion

Abstract

Samples of water inside and outside an exclusion zone (EZ), created by Nafion swollen in water, were irradiated at the wavelength l = 1264 nm, which stimulates the electronic transition of dissolved oxygen from the triplet state to the excited singlet state. This irradiation induces, after a long latent period, chemiluminescence self-oscillations in the visible and near UV spectral range, which last many hours. It occurs that this effect is EZ-specific: the chemiluminescence intensity is twice lower than that from the bulk water, while the latent period is longer for the EZ. Laser irradiation causes accumulation of H2O2, which is also EZ-specific: its concentration inside the EZ is less than that in the bulk water. These phenomena can be interpreted in terms of a model of decreasing O2 content in the EZ due to increased chemical activity of bisulfite anions (HSO3−), arisen as the result of dissociation of terminal sulfonate groups of the Nafion. The wavelet transform analysis of the chemiluminescence intensity from the EZ and the bulk water gives, that self-oscillations regimes occurring in the liquid after the latent period are the determinate processes. It occurred that the chemiluminescence dynamics in case of EZ is characterized by a single-frequency self-oscillating regime, whereas in case of the bulk water, the self-oscillation spectrum consists of three spectral bands.

Exclusion Zone Phenomena in Water—A Critical Review of Experimental Findings and Theories

“…For the case of highly hydrophillic surfaces these findings have now been reproduced by several independent research groups [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 ] and constitute a genuine physical phenomena which is in need of a theoretical explanation. A few experimenters have reported EZs near metal surfaces [ 12 , 13 , 14 ], and one has reported it for cellulose [ 15 ].…”

Активные Формы Кислорода В Водных Средах (Обзор)

“…Чем выше плотность фиксированного отрицательного заряда на смачиваемой поверхности, чем больше площадь этой поверхности, тем больше электронная емкость формируемой этой поверхностью EZ-воды. В EZ-зоне образование Н 2 О 2 при освещении светом 1274 nm (в полосе поглощения кислорода) идет слабее, чем в объемной воде, латентный период длиннее, а осцилляции хемилюминесценции имеют одну частоту вместо трех частот в объемной воде [146].…”

Dynamics of Nafion membrane swelling in H2O/D2O mixtures as studied using FTIR technique

“…38 Using the FTIR technique, it is possible to effectively study the diffusion of water molecules inside the pores of a polymer membrane. 39 Note finally that we in our group also investigate the properties of Nafion soaked in various liquids with the chemiluminescence 40…”