Publications by authors named "Askarova G"

The coronavirus that causes serious acute respiratory syndrome. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is still a major problem in public health and biomedicine. Even if there is no cure for it, the infection is still progressing naturally, and the only time that optimal treatment choices, such as doxycycline, work is at the beginning of the infection.

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Molecular photocatalysis and photoelectrocatalysis have been widely used to conduct oxidation-reduction processes ranging from fuel generation to electroorganic synthesis. We recently showed that an electrostatic potential drop across the double layer contributes to the driving force for electron transfer (ET) between a dissolved reactant and a molecular catalyst immobilized directly on the electrode surface. In this article, we report voltage-driven molecular photoelectrocatalysis with a prevalent homogeneous water oxidation catalyst, (bpy)Cu (II), which was covalently attached to the carbon surface and exhibited photocatalytic activity.

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The foliage of the small-leaved lime (Tilia cordata) is characterised by the nerve axils being grown by non-glandular trichomes, which trait contributes to the enhanced retention of the particulate matter (PM). This fact may disturb the ecological service of T. cordata related to the structure of its leaves, which is to provide acarodomatia (micro-shelters) for the predatory mites of the Phytoseiidae family.

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Scanning electrochemical microscopy (SECM) has been extensively used for mapping electrocatalytic surface reactivity; however, most of the studies were carried out using micrometer-sized tips, and no quantitative kinetic experiments on the nanoscale have yet been reported to date. As the diffusion-limited current density at a nanometer-sized electrode is very high, an inner-sphere electron-transfer process occurring at a nanotip typically produces a kinetic current at any attainable overpotential. Here, we develop a theory for substrate generation/tip collection (SG/TC) and feedback modes of SECM with a kinetic tip current and use it to evaluate the rates of hydrogen and oxygen evolution reactions in a neutral aqueous solution from the current-distance curves.

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Particulate bismuth vanadate (BiVO) has attracted considerable interest as a promising photo(electro)catalyst for visible-light-driven water oxidation; however, overall water splitting (OWS) has been difficult to attain because its conduction band is too positive for efficient hydrogen evolution. Using photoscanning electrochemical microscopy (photo-SECM) with a chemically modified nanotip, we visualized for the first time the OWS at a single truncated bipyramidal microcrystal of phosphorus-doped BiVO. The tip simultaneously served as a light guide to illuminate the photocatalyst and an electrochemical nanoprobe to observe and quantitatively measure local oxygen and hydrogen fluxes.

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Particulate photocatalysts for the overall water splitting (OWS) reaction offer promise as devices for hydrogen fuel generation. Even though such photocatalysts have been studied for nearly 5 decades, much of the understanding of their function is derived from observations of catalyst ensembles and macroscopic photoelectrodes. This is because the sub-micrometer size of most OWS photocatalysts makes spatially resolved measurements of their local reactivity very difficult.

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The integration of heterogeneous electrocatalysis and molecular catalysis is a promising approach to designing new catalysts for the oxygen evolution reaction (OER) and other processes. We recently showed that the electrostatic potential drop across the double layer contributes to the driving force for electron transfer between a dissolved reactant and a molecular catalyst immobilized directly on the electrode surface. Here, we report high current densities and low onset potentials for water oxidation attained using a metal-free voltage-assisted molecular catalyst (TEMPO).

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The use of scanning electrochemical microscopy (SECM) for nanoscale imaging of photoelectrochemical processes at semiconductor surfaces has recently been demonstrated. To illuminate a microscopic portion of the substrate surface facing the SECM probe, a glass-sealed, polished tip simultaneously served as a nanoelectrode and a light guide. One issue affecting nanoscale photo-SECM experiments is mechanical interactions of the rigid optical fiber with the tip motion controlled by the piezo-positioner.

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Heterogeneous electrocatalysis and molecular redox catalysis have developed over several decades as two distinct ways to facilitate charge-transfer processes essential for energy conversion and storage. Whereas electrocatalytic reactions are driven by the applied voltage, molecular catalytic processes are driven by the difference between standard potentials of the catalyst and the reactant. Here, we demonstrate that the rate of electron transfer between a dissolved reactant and a molecular catalyst immobilized directly on the surface of a carbon nanoelectrode is governed by combination of chemical driving force and electrostatic potential drop across the double layer.

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This paper reports survey-based data on the diagnosis and management of genital herpes simplex virus (HSV) infection in 14 countries of the Eastern European Network for Sexual and Reproductive Health (EE SRH). Only 43% of the countries could provide the number of genital HSV cases recorded at national level. Eighty-six percent of countries employed syndromic management in cases of genital ulcer disease.

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