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[en] The expressions in description of a frequencies spectrum if thermal mode of electrolytes in a wide range of frequencies ware received. Also, the cases of low an high frequencies are considered. There was shown, that in a hydrodynamic mode attenuation of thermal modes depends on coefficient conductivity, but on a high-frequencies of this mode, depends only on the high-frequency module thermoelasticity
[en] The finely-divided particles of a selected phosphor material are combined with an aqueous solution of a suitable binder material to form an emulsion which is spread uniformly on the smooth surface of a support member. The wet coating is then heated to remove the water and the resulting film sintered to produce a strong, continuous film. The film is then peeled from the support member resulting in a uniformly thick sheet of phosphor and binder from which dosimeters can be cut or stamped to any desired size
[en] Early, yet still often-cited, mathematical models for electromagnetic stirring (EMS) in continuous casting are re-examined and found to contain a surprising anomaly: the solutions obtained were not unique. Analysis for the case of a round billet under rotary EMS shows how to avoid this behavior, whilst still making use of the experimental data that motivated the original models. The relevance of this result for current-day modeling of EMS is highlighted, particularly in the context of modulated EMS.
[en] The cross section for the Raman scattering of light in electron superlattices is calculated, including a finite probability for tunneling between layers. In the long-wavelength approximation, i.e., for the case in which the momentum transfer is much smaller than the reciprocal of the superlattice constant, it is shown that an unscreened component of single-particle scattering arises when there is a finite tunneling. This unscreened component may be substantially greater than the scattering cross section in a lattice without tunneling. Competing unscreened-scattering mechanisms, unrelated to tunneling, are analyzed
[en] This paper proposes an approach for generation portfolio allocation based on mean-variance-skewness (MVS) model which is an extension of the classical mean-variance (MV) portfolio theory, to deal with assets whose return distribution is non-normal. The MVS model allocates portfolios optimally by considering the maximization of both the expected return and skewness of portfolio return while simultaneously minimizing the risk. Since, it is competing and conflicting non-smooth multi-objective optimization problem, this paper employed a multi-objective particle swarm optimization (MOPSO) based meta-heuristic technique to provide Pareto-optimal solution in a single simulation run. Using a case study of the PJM electricity market, the performance of the MVS portfolio theory based method and the classical MV method is compared. It has been found that the MVS portfolio theory based method can provide significantly better portfolios in the situation where non-normally distributed assets exist for trading. (author)
[en] Error analysis is very important to experimental designs. The error analysis of the determination of activity coefficients for a binary system via the isopiestic method shows that the error sources include not only the experimental errors of the analyzed molalities and the measured osmotic coefficients, but also the deviation of the regressed values from the experimental data when the regression function is used. It also shows that the accurate chemical analysis of the molality of the test solution is important, and it is preferable to keep the error of the measured osmotic coefficients changeless in all isopiestic experiments including those experiments on the very dilute solutions. The isopiestic experiments on the dilute solutions are very important, and the lowest molality should be low enough so that a theoretical method can be used below the lowest molality. And it is necessary that the isopiestic experiment should be done on the test solutions of lower than 0.1 mol . kg-1. For most electrolytes solutions, it is usually preferable to require the lowest molality to be less than 0.05 mol . kg-1. Moreover, the experimental molalities of the test solutions should be firstly arranged by keeping the interval of the logarithms of the molalities nearly constant, and secondly more number of high molalities should be arranged, and we propose to arrange the experimental molalities greater than 1 mol . kg-1 according to some kind of the arithmetical progression of the intervals of the molalities. After experiments, the error of the calculated activity coefficients of the solutes could be calculated from the actually values of the errors of the measured isopiestic molalities and the deviations of the regressed values from the experimental values with our obtained equations
[en] Highlights: • Regular solution theory in Tween 85/Triton X100 or Tween 85/Triton X165 micelles is not acceptable. • In interval of temperature 303.15–308.15 K Triton X165 has higher stabilizing effect of micelles. • Above 308.15 K in both types of mixed micelles antagonistic effects exist. - Abstract: Binary surfactant mixtures of Tween 85/Triton X100 and Tween 85/Triton X165 have been investigated in water solution over the temperature range from 273.15 K to 323.15 K. At the temperatures of 273.15 K and 283.15 K between different building units of binary mixed micelles, synergistic interactions exist whose size is not affected by difference in length of the polyoxyethylene chains. At higher temperatures, the longer polyoxyethylene chain of Triton X165 shows a more stabilizing effect in mixed micelle with Tween 85 than in mixed micelles of Tween 85/Triton X100. For the investigated binary mixed micelles, regular solution theory approximation about zero value of excess entropy of binary mixed micelle formation cannot be accepted.
[en] Recording of elementary holographic gratings in polymer films and solutions coloured with organic dyes has been investigated. Possible mechanisms of modifying a recorded grating by an additional laser pulse are considered. A theoretical model is proposed to describe the processes of recording/relaxation and modification of gratings recorded on triplet states of photochrome molecules; the predictions of this model are found to be in good agreement with the experimental data. (holography)
[en] Loofah fiber, an economical adsorbent material, was first developed for the methyl green (MG) removal from aqueous solutions. The loofah fibers were characterized by SEM, FTIR, N_2-BET and the potentiometric titration. The pH, contact time and temperature were examined extensively. The adsorption of MG on loofah fiber increased very quickly in the pH range 3.0 to 7.0, remaining a high level at pH>7.0. The kinetics of adsorption of MG on the loofah fiber was proved to coincide with pseudo-second-order kinetic models (r"2>0.99) very well. Langmuir isotherm was demonstrated to fit the experimental data better than Freundlich isotherm model. Monolayer adsorption capacity increased with the increase of temperature. Thermodynamic constants were evaluated, and the results indicated that MG adsorption onto loofah fiber was feasible, spontaneous and endothermic. The high removal efficiency of MG on loofah fiber suggested that the loofah fiber was suitable material in MG pollution cleanup
[en] In this article was investigated the acoustic emission at decomposition reactions solid-solution type and determination the connection between kinetic parameters of chemical reaction and characteristics of chemical acoustic emission for the further using of given method in chemical technologies