This note presents the results of experiments made in order to determine the nature of the luminescence lines associated with dislocations in silicon. This type of luminescence has been first described in our paper /1/.The experiments have been carried out at T = 4 . 2 and 7 7 K by means of measuring photoluminescence spectra under uniaxial deformation along < loo), (110), and (111) The transformation of spectra in the vicinity of the lines D1 and D2 under deformation is in principle quite different. The results for deformation along < 110) direction a r e shown in Fig. 1 (curves 2 , 3). Both components of the lines D1, D2

An algorithm for the calculation of solar cell parameters (series and parallel resistance, diode coefficient, reverse current density) calculation from its current-voltage characteristics at fixed illumination intensity is proposed. The possibility of determining the p-n junction depth on the basis of spectral dependencies of diode photocurrent at different values of the applied bias voltage is shown.

Intrinsic photoluminescence (PL) of undoped and of B-, Ag-or Er-doped TlInS 2 layered single crystals was investigated by confocal spectroscopy. It is found that position and intensity of PL spectral peak at 2.4 eV is vastly dependent on the excitation light incidence and polarization relative to crystallographic directions. For the normal incidence to the layer plane k||c, a significant Stokes shift between the PL peak in respect to exciton absorption energy is highlighted. The shift increases to 80 meV around the crystal phase transformations region of 200 K. We show that presence of B and Ag impurity do not diminish the intrinsic PL emission while Er atoms incorporation enhances it substantially and modifies a fine excitonic line structure in the ferroelectric phase at low T. The obtained results imply out-of-layer plain oriented 2D excitons in TlInS 2 existing at various crystal phases which are influenced by related interlayer stresses.& 2017 Elsevier B.V. All rights reserved. the TlInS 2 exhibit formation a new shallow donor-acceptor pair (DAP) photoluminescence band after low temperature thermocycling [6]. In addition, an imprint of photoactive trap self-polarization in the external electric field under different temperatures was observed and attributed to the dipolar origin of some Contents lists available at ScienceDirect

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The paper is devoted to the investigation of the stability of gas-liquid mixtures. Investigations of the suppression of the coalescence of gas bubbles in a liquid at various concentrations and composition of dissolved salts were carried out on a facility containing a laser diode with a telescopic system, a glass column, a bubbler, a gas supply system, a laser reception unit with a breaker, a lens and a photodiode, an oscillograph and a computer. The value of coalescence suppression was determined from the change in the transmittance of laser radiation through a column with bubbles in the liquid. In addition, bench tests were carried out on the characteristics of ejectors and a multistage centrifugal pump when creating and pumping gas-liquid mixtures using fresh water as a liquid, as well as aqueous solutions with various concentrations of NaCl. It has been experimentally determined that there are zones of rational salt concentrations and composition in which the coalescence of gas bubbles is suppressed due to the expression of repulsive forces between bubbles charged negatively in aqueous solutions of electrolytes. At smaller and higher concentrations coalescence suppression does not occur, and gas bubbles actively join with each other. The effect of cations and anions in aqueous solutions of various salts on the process of suppressing the coalescence of gas bubbles in a liquid is revealed. Investigations of the produced water from Samodurovskoye field showed that its composition helps to suppress coalescence of bubbles, but the addition of a certain amount of NaCl enhances the suppression of coalescence. When the water-gas mixture prepared by the ejector with using fresh water was pumped was pumped out on bench and the coalescence of gas bubbles was not maintained, the pressure developed by the multistage centrifugal pump decreased greatly with increasing gas content at the pump inlet. When using of NaCl aqueous solutions in the field of rational concentrations, a multistage centrifugal pump began to operate much better on a water-gas mixture. This was due to the suppression of the coalescence of gas bubbles in the liquid and the prevention of the formation of large gas caverns in the inter-blade channels of the pump. Field studies of the pump-ejecting system for SWAG injection on Samodurovskoye field were also carried out. The obtained results can be used for utilization of associated gas by water-gas injection, as well as in various oil production technologies, where gas-liquid mixtures move (completion, operation of wells, gathering oil, gas and water).