Ionic conductivity in poly(vinyl butyral) based polymeric electrolytes: Effect of solvents and salts

Li⁺ conductive solid polymeric electrolytes (SPEs) have been prepared by complexing Li salts LiX (X = I, SCN, CLO4, CF3SO3) with poly(vinyl butyral) (PVB) an amorphous polymer with a low T_g value and well known for its outstanding laminating properties. These self-supporting SPEs have been prepared by the solution cast technique using cyclohexanone, tetrahydrofuran, and n-butyl alcohol as solvents. The XRD and DSC investigations correlated to measured ionic conductivities have revealed that in addition to the amorphous nature of the resulting complex, its T_g value, the concentration and the values of the lattice energies of the complexing salts, the solvent used in making the SPEs also govern the value of ionic conductivity. Highest ionic conductivity values attained in SPEs made with n-butyl alcohol are explained in terms of the interception of the hydrogen bonding due to solvation.     

Sequential discrete multilevel automated system for recording electron-diffraction patterns

This article considers a discrete sequential multilevel automated system for recording electron-diffraction patterns. A comparative analysis is presented, along with experimental results that make it possible to evaluate the effectiveness of the technical decisions on which the device is based. The general design of the system is presented. Translated from Izmeritel'naya Tekhnika No. 5, pp. 16–18, May, 1996.     

The unsteady-state thermohydraulic calculation of a stacked core

NIKIÉT. Translated from Atomnaya Énergiya, Vol. 75, No. 4, pp. 265-269, October, 1993.     

The solubility of tungsten in molten iron

The solubility of tungsten in iron has been determined at 1560–1620°C by successively saturating molten iron with tungsten while ensuring a uniform distribution of the content over the height. The temperature dependence of the solubility over that temperature range is described by a Schröder equation: C_s=(3.94±0.11)×10³e-(84.4±0.4)/RT.     

Void fraction and pressure drop in two-phase liquid metal flows in channels

Experimental results on void fraction and friction pressure drop in vapour-potassium flows in the high-vapour-quality region up to unity are presentéd. The experimental data obtained and the pertinent results of other authors are generalized, and empirical relationship are suggested to calculate void fraction and pressure drop in two-phase liquid metal flows for channels of various configurations and orientations. The relationships are valid within the range of vapour qualities from almost zero to unit. The experimental data prove the mass velocity to have no influence on the hydrodynamic characteristics within the range of the parameters investigated. It is found in the experiments with heat supply that friction pressure losses are smaller than those for adiabatic conditions. It is shown that this result is in good correspondence with the model of the effect of injection in a boundary layer on the value of shear stresses between cases.     

Investigations of a two-wave laser refractometer

A two-wave laser interference refractometer for measuring the refractive index of air, pure gases, and gaseous mixtures is described. An algorithm for calculating the results of measurements using the method of coincidence of fractional parts of the orders of interference is given.Translated from Izmeritel'naya Tekhnika, No. 7, pp. 29–31, July, 1993.     

Numerical investigation of nitriding of refractory metals (with account of the phase constitution diagrams for metal-gas systems)

A mathematical model of dissolution of gas in a metal is suggested with account of phase formation in accordance with the phase constitution diagram (PCD). The stage-by-stage saturation process to the final product formation is shown for an individual particle, through which a reaction wave passes, depending on the diffusion permeability of the metal and solubility conditions that obey Sieverts's law. The effect of the filtration supply of the oxidant to the reaction zone and the process exothermicity on the course of the process is shown.Institute of Structural Macrokinetics, Russian Academy of Sciences, Chernogolovka, Russia. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 65, No. 4, pp. 447–450, October, 1993.     

Solar/UV-induced photocatalytic degradation of three commercial textile dyes.

The photocatalytic degradation of three commercial textile dyes with different structure has been investigated using TiO(2) (Degussa P25) photocatalyst in aqueous solution under solar irradiation. Experiments were conducted to optimise various parameters viz. amount of catalyst, concentration of dye, pH and solar light intensity. Degradation of all the dyes were examined by using chemical oxygen demand (COD) method. The degradation efficiency of the three dyes is as follows: Reactive Yellow 17(RY17) > Reactive Red 2(RR2) > Reactive Blue 4 (RB4), respectively. The experimental results indicate that TiO(2) (Degussa P25) is the best catalyst in comparison with other commercial photocatalysts such as, TiO(2) (Merck), ZnO, ZrO(2), WO(3) and CdS. Though the UV irradiation can efficiently degrade the dyes, naturally abundant solar irradiation is also very effective in the mineralisation of dyes. The comparison between thin-film coating and aqueous slurry method reveals that slurry method is more efficient than coating but the problems of leaching and the requirement of separation can be avoided by using coating technique. These observations indicate that all the three dyes could be degraded completely at different time intervals. Hence, it may be a viable technique for the safe disposal of textile wastewater into the water streams.