Recyclization of 4-oxo-1,3-benzoxazinium perchlorates to 4-substituted 5-(o-hydroxyphenyl)-1,2,4-oxadiazolium salts

Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 280–281, February, 1992.     

The viscosity and density of the methanol + n-nonane, ethanol + n-nonane, and ethanol + n-decane systems

This work presents the results obtained in measurements of the kinematic viscosity and density of the methanol-n-nonane, ethanol-n-nonane, and ethanol-n-decane systems at various temperatures and low n-alkane concentrations (within the concentration range of miscibility). The dynamic viscosities of these systems at 298.15 K were calculated according to free volume theory. The results substantiated the existence of an anomaly in the behavior of viscosity of the methanol-n-nonane system (positive Δlnη values) and its absence for the ethanol-n-alkane systems.     

Dependence of the volume and viscosity of naphthalene-ethanol-octane solutions on composition at 298 K

The solubility of naphthalene in ethanol-octane mixtures was measured by the isothermal saturation method. The solution densities were determined and the partial and apparent molar volumes of naphthalene were calculated. The viscosity was measured with an Ubbelohde viscosimeter with a suspended level. All measurements were performed at 298.15 K. The results were discussed based on interactions in solution.     

Electrochemical performance of lithium titanate anode fabricated using a water-based binder

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Arak’s inequalities for concentration functions and the Littlewood–Offord problem

In this paper we study the behavior of concentration functions of weighted sums of independent random variables with respect to the arithmetic structure of coefficients. Recently, Tao and Vu formulated a so-called Inverse Principle in the Littlewood–Offord problem. We discuss the relations between this Inverse Principle and a similar principle formulated for sums of arbitrarily distributed independent random variables formulated by T. Arak in the 1980’s.     

Density and viscosity of methanol-heptane (octane) mixtures at low alkane concentrations over the temperature range 288.15–328.15 K

An Anton Paar 4500 densimeter was used to measure the density of methanol-heptane and methanol-octane solutions in the region of low alkane concentrations over the temperature range 288.15–328.15 K. The experimental data were used to calculate the apparent, partial, and excess molar volumes of alkanes. Viscosity was measured with an Ubbelohde viscometer at 298.15 K. The NMR spectra were recorded on a Bruker Avance III BioSpin spectrometer. The physicochemical characteristics of methanol-heptane and methanol-octane mixtures were considered in combination with molecular dynamics simulation results. The conclusion was drawn that methanol was structured in mixtures with heptane at concentrations of 0.04–0.06 alkane mole fractions. This peculiarity was not observed in mixtures with other alkanes.     

Dispersion of single-walled carbon nanotubes in alcohol-cholic acid mixtures

A procedure for dispersing single-walled carbon nanotubes (SWNTs) for the preparation of suspensions with high concentrations of individual nanotubes in various solvents was described. The most stable suspensions were obtained from a mixture of ethanol with cholic acid at an acid concentration of 0.018 mol/kg.     

Nanocomposite electrode materials based on poly(3,4-ethylenedioxythiophene) with incorporated gold and palladium: Preparation and morphology study

Chemical deposition of ultrafine gold and palladium particles into poly(3,4-ethylenedioxythiophene) matrix has yielded the metal-containing polymer composites. Their structure has been studied as affected by duration of reduced polymer immersion into the metal salts solution, and by concentration of the latter. Morphology features of the composite films (size and concentration of metal particles) have been elucidated by scanning and transmission electron microscopy. The mixed clusters have been formed predominantly in the course of preparation of bimetal composite films via sequential deposition of gold and palladium; the isolated palladium clusters nucleate slower due to the gold-palladium alloys formation. Longer deposition of the metals leads to increase in the nanoparticles size and their concentration in the composite. Properties of the prepared materials have been demonstrated using the model electrochemical reactions.     

ZrO2–Sc2O3 Solid Electrolytes Doped with Yb2O3 or Y2O3

Russian Journal of Electrochemistry - The effects of the Y2O3 and Yb2O3 co-doping impurities on the transport characteristics and stabilization of the cubic phase in solid solutions based on...