Plasma electrolytic synthesis and characterization of pH-sensitive TiO2-ZrO2-ZrTiO4-CeOx films on titanium

Journal of Solid State Electrochemistry - The Ti/TiO2 + ZrO2, Ti/TiO2 + CeOx, and Ti/TiO2 + CeOx + ZrO2 composites, including Y-doped ones, have been...     

Thermal air-oxidized coating on Yb14−xRExMnSb11 ceramics

Journal of Thermal Analysis and Calorimetry - A high sublimation rate of Yb14MnSb11 as a promising thermoelectric material at working temperatures is a critical factor for its space power...     

Behavior of a ruthenium-titanium oxide film electrode (RTOE) in potentiometry

Polyfunctional properties of a ruthenium-titanium oxide electrode in the absence of polarization and the possibility of its application to the potentiometric detection of iron(III) titration with an ethylenediaminetetraacetic acid solution, acid-base and redox reaction types have been demonstrated. Mechanisms of reactions determining the potentials of electrodes of this type have been investigated by a number of methods.     

An effect of heat processing on catalytic activity of a system MnO x ,SiO2/TiO2/Ti

An effect of annealing in air at temperatures 250, 350, 500, and 700°C on composition, surface structure, and catalytic activity in CO oxidation of a system MnO _x ,SiO₂/TiO₂/Ti formed by combining methods of plasma electrolytic oxidation and impregnation was examined.     

Isotherm of α-tocopherol adsorption on acid-activated clinoptilolite tuff

Adsorption of α-tocopherol from ethanol solution on clinoptilolite tuff activated with 4.0 M HCl is studied. α-Tocopherol adsorption isotherm is analyzed using the Langmuir, Freundlich, and Redlich-Peterson adsorption theories. The adsorption of α-tocopherol from dilute solutions on this sorbent is ascertained to be described by the Langmuir model.     

Aspect-ratio dependent oscillatory thermocapillary convection in the floating half zone

The dependency of the critical Marangoni number on the geometrical aspect ratio of the floating half zone is essential to predict the onset of oscillatory thermocapillary convection.The experimental studies in the microgravity conditions on floating half zones of several centimeters in diameter have predicted that the critical Marangoni number increases with the increasing aspect ratio,and the terrestrial experimental studies have predicted the contradictory conclusion for floating half zones of several mil...     

One-Pot Synthesis of N-2,4-Enyne Cyclic Amines

Russian Journal of General Chemistry - Stereoselective synthesis of N-2,4-enyne cyclic amines was performed by one-pot animation of individual isomers of 1,3-dichloropropene and the subsequent...     

Modification of Arabinogalactan Isolated from Larix sibirica Ledeb. into Sulfated Derivatives with the Controlled Molecular Weights

The process of sulfation of arabinogalactan—a natural polysaccharide from Larix sibirica Ledeb.—with sulfamic acid in 1,4-dioxane using different activators has been studied for the first time. The dynamics of the molecular weight of sulfated arabinogalactan upon variation in the temperature and time of sulfation of arabinogalactan with sulfamic acid in 1,4-dioxane has been investigated. It has been found that, as the sulfation time increases from 10 to 90 min, the molecular weights of the reaction products grow due to the introduction of sulfate groups without significant destruction of the initial polymer and sulfation products. Sulfation at 95 °C for 20 min yields the products with a higher molecular weight than in the case of sulfation at 85 °C, which is related to an increase in the sulfation rate; however, during the further process occurring under these conditions, sulfation is accompanied by the destruction and the molecular weight of the sulfated polymer decreases. The numerical optimization of arabinogalactan sulfation process has been performed. It has been shown that the optimal parameters for obtaining a product with a high sulfur content are a sulfamic acid amount of 20 mmol per 1 g of arabinogalactan, a process temperature of 85 °C, and a process time of 2.5 h.     

Formation of RNA oligonucleotides over the mineral surface preliminary irradiated with UV light

An opportunity of the abiogenic formation of oligonucleotides over the surface of montmorillonite particles, preliminarily irradiated with UV light, was found upon the adsorption of mononucleotides on this surface. A probable mechanism of such a synthesis is suggested.