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Copyright of Cybernetics & Systems Analysis / Kibernetiki i Sistemnyj Analiz is the property of V.M. Glushkov Institute of Cybernetics of NAS of Ukraine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Automatic Welding / Avtomatitcheskaia Svarka is the property of International Association Welding (Paton Publishing House) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper considers forming interphase adsorption layers in emulsions and foams using a surfactant mixture and milk proteins. The main objective of the study is to substantiate using the surfactant mixture and milk proteins, which define the dispersed system stability. The emulsion formation process at temperatures above the fat crystallization temperature was carried out by determining the boundary shear stress, formed interphase adsorption layers, which was performed in 4×3600 s (interphase adsorption layer formation time that has the largest value of the boundary shear stress at a temperature of 20±1 °C. Behavioral mechanisms of surfactants and milk proteins on the interphase surface were substantiated in the paper in order to determine their rational concentrations. The presented method allows to define the layer strength of the system without surfactants and, with introducing the surfactant mixture, determine the rational composition of the surfactant mixture, which allows to vary the strength of interphase adsorption layers and as a result produce foam-emulsion systems with the high foaming ability, stability and ductility. Research results can be applied by food technologists, as well as technologists specialized pastry shops to create foam-emulsion systems such as creams, souffle, ice-cream, etc. We propose to use milk proteins and surfactant mixture to control the stability of dispersed systems such as foams and emulsions, as well as stable foam-emulsion systems. [ABSTRACT FROM AUTHOR]

Copyright of Proceedings of the National Academy of Sciences of Armenia. Mechanics is the property of National Academy of Sciences of the Republic of Armenia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Promising direction of heat-transfer intensification is modification of the liquids used as coolants or working bodies for various kinds of equipment. Within this framework the usage of nanofluids (suspensions of nano-size particles (up to 100 nm) in a base fluid) is proposed. The results obtained have shown that the additive of Al2O3 nanoparticles to isopropanol increases the heat transfer coefficient during pool boiling up to 10-26%. However, such effect was found only at the low heat flux densities. At the high heat flux densities the presence of the nanoparticles in isopropanol leads to decreasing the heat-transfer coefficient. According to the authors, this is the result of nanofluid destabilization. It is shown that the complex nature of nanoparticles Al2O3 effect on the changes in heat-transfer coefficient is related to a combined contribution of different factors: interaction of nanoparticles with heating surfaces, changing in thermal properties of nanofluids compared to the base fluid, hydrodynamic radius of nanoparticles and their concentration in isopropanol. According to the authors, the possible reason of nanofluid destabilization during pool boiling may be the destruction of heterogeneous micelles on the heater surface. Therefore, the study of nanofluids pool boiling and correct interpretation of the collected data should consider the stability, concentration changes of nanofluid and heating surface properties. The study on hydrodynamic radius of nanoparticles was carried out using experimental setup wherein DLS method has been realized. The results has shown increasing in hydrodynamic radius from 53 to 86 nm with an increasing in the mass fraction of nanoparticles from 0.036 to 4.2 wt.%. The experiments to determine the stability of nanofluid has shown that the system remains stable throughout the period of the experiment (100 hours), temperatures interval (20-70 °C) and the mass fraction of nanoparticles (0.036-4.2 wt.%). In addition, in this paper, the dependence of the mass fraction of Al2O3 nanoparticles in isopropanol on the value of the transmitted light through the nanofluid was obtained. The magnitude of the transmitted through the nanofluid light is proportional to the mass fraction of nanoparticles. [ABSTRACT FROM AUTHOR]

The paper substantiates the conditions of seismic stability in the rock mass with cavities, on which protected objects are located, under constant seismic effects of mass explosions in quarries. Based on the ray-tracing method, a mathematical model of the interaction between longitudinal and transverse waves with a spherical cavity has been developed. An algorithm has been elaborated for determining the total static and dynamic loads along the spherical cavity perimeter from seismic explosion waves falling on the interface. The regularities of joint action of static loads have been determined, when located above the objects cavity, with allowance for the effect of the mass of cavity ceiling, the mass of the protected object above it and dynamic loads in the rock mass, and under the plane wave front fall on the cavity from different directions. The dependences of the change of total stresses referred to the incident wave stress at the interface of the rock mass and the cavity depending on the coordinate on its surface have been set. It has been established that the most dangerous points of cavity surface, in which destruction is likely to occur, are the cases when the seismic wave front falls on the cavity from the bottom directions typical for blasting operations in deep quarries. Under the arbitrary angles of the wave incidence on the cavity the stresses rearrange along the perimeter, which under different circumstances might lead to the mass breach and the fall of the protected objects, located above it, under the ground. [ABSTRACT FROM AUTHOR]

Copyright of KazEU Khabarshysy/ Vestnik KazEU is the property of Narxoz University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of KazEU Khabarshysy/ Vestnik KazEU is the property of Narxoz University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)