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The process of water treatment by nanoparticles is one of the most considerable subjects in the cross-field of hydrodynamics, chemistry, and mathematics. This paper is dedicated to the case of the flows that appear when squeezing and stretching a channel with mixing of water, nanoparticles, and contaminants. It is assumed that fluid is homogeneous at the starting moment, the parameters of the nanoparticles and contaminants are known, and there is a constant non-homogeneous magnetic field applied to the system. The flow starts moving when the walls of the channel shift to each other. Exact and numerical solutions of the system of ordinary differential equations are used to obtain the results. The article gives an answer to the question about stability of the flow and proposes the technique to evaluate the essential characteristics of the system to achieve the treatment process efficiency. The main result is that the considered system shows excellent properties concerning purification of water on the selected part of the squeezing stage. This effect does not appear without a magnetic field. The mentioned properties are: decreasing of nanoparticle concentration to zero inside of the unsteady layer under magnetic field close to 1 T and this effect stays until the channel become about 10% of initial width as a result of the squeezing. [ABSTRACT FROM AUTHOR]

The article presents data on experiments related to the start-up process of an automobile engine using capacitive energy storage. It is shown that capacitive energy storage devices can be used for efficient start-up of an internal combustion engine. The aim of the article was to study the systems of electric start of vehicles combustion with capacitive energy storage as source of electric energy using a mathematical apparatus that allowed analyzing the process of starting a vehicle engine with capacitive energy. In the course of work, analytical dependences on the time and angle of rotation of the crankshaft of the internal combustion engine (number of working strokes) of the main parameters of the electric starter starting system with a constant moment of resistance on the shaft of the internal combustion engine were obtained. Mathematical calculations and simulation of operating modes in specialized software products were carried out. The results of the experiment showed that the process of scrolling the internal combustion engine with an electric starter when it is powered from capacitive energy storage devices differs significantly from the process of scrolling when powered from a rechargeable battery. Due to the large proliferation of batteries in vehicles and the search for alternative technological solutions to them, it can be said that the results obtained in this article are of practical value in the framework of modern electrical equipment technology. [ABSTRACT FROM AUTHOR]

The thermal applications of nanofluids are extremely high and researchers have suggested multidisciplinary applications of nanomaterials in heat transfer problems, thermal systems, chemical industries, thermal energy systems, nuclear processes, extrusion mechanism, etc. The aim of this work is to discuss thermal properties of nanofluids for Poiseuille flow with hydrodynamic effects. The magnetohydrodynamic Poiseuille flow of thermo-capillary levels of nanoparticles with apparent viscosity nanofluids is focused. The graphene oxide (GO) nanoparticles are immersed in water-based fluid. The formulated system is solved numerically by using the Chebyshev collocation method. The mathematical technique Qualitat and Zuverlassigkeit (QZ) is applied to find out eigenvalues from comprehensive Orr–Sommerfeld technique. It is noted that the flow of nanofluids becomes stable due to the wave number and magnetic field. The Reynolds and Prandtl numbers have dynamic role on destabilizing the nanofluids transportation. The outcomes of this study are utilized in drug-delivery systems, photodynamic therapy and delivery of antitumor. [ABSTRACT FROM AUTHOR]

In this paper, we have discussed some new operations and results of set theory for complex fuzzy sets (CFSs). Moreover, we developed the basic results of CFSs under the basic operations such as complex fuzzy simple difference, bounded sum, bounded difference, dot product, bounded product, union, intersection, and Cartesian product. We explored the CFSs and discussed the related properties with examples such as complex fuzzy bounded sum over the intersection, complex fuzzy dot product over the union, etc. Identifying the reference signals under the environment of CFSs have always been a challenging. Many algorithms based on set theoretic operations and distance measures have been proposed for identifying a reference signal using any common system. But linear time invariant (LTI) system is considered easy to analyze the linear and time-varying signals. We used CFSs in signals and systems. We developed an algorithm based on convolution product and LTI system under the complex fuzzy environment. We identified a high degree of resemblance (reference signal) of the received signals to the reference signal in a linear time-invariant (LTI) system that receives an input signal and produces an output signal. [ABSTRACT FROM AUTHOR]

We investigated the relation of the age trajectory of physiological indicators of the average metabolic activity of organisms in a population to the age-specific population mortality rate. We show that a metabolic rate indicator (MRI) can be estimated using traditional physiological measures, such as homeostatic serum glucose concentration, vital capacity, and such. Estimates of the MRI were made from data collected in the Multiple Risk Factor Intervention Trial (MRFIT) study. The relation of the empirical mortality rate and MRI was also tested using MRFIT data. The age trajectory of MRI was evaluated using Swedish mortality data. The mortality results reproduce the "Strehler and Mildvan effect." The average rate of decline of MRI with age coincides with estimates predicted by Strehler using other methods. Possible extensions of the method are discussed. [ABSTRACT FROM AUTHOR]

In recent years, much attention of developers of integrated microcircuits is given to designing novel types of microprocessors, development, and mastery of technologies of both multilayer 3D integrated circuits and making devices based on complex semiconductors. The aim of the present work is to study thermal processes in the Al-Ti-Si multilayer system up to the development of degradation processes. The degradation issues in aluminum metallization with titanium sublayer deposited onto silicon surface are considered. The evolution of processes of irreversible destruction of film conductor under passage through it of single square-wave current pulses with energy up to 300 mJ and duration of 50 ... 1000 µs was analyzed. It was found that, under the action of a single square-wave current pulse with a duration of no more than 80 µs and energy of 85 mJ, the priority process of structural damage is the melting of the metal film. Increasing pulse duration (T > 80 µs) changes the priority of thermal degradation, and contact melting becomes the main mechanism of structure damage. It was also found that isothermal annealing leads to improving system heat-conducting properties and increasing critical current densities. This is related to the improvement of adhesion properties of the structure as well as with phase transformations in the Al-Ti-Si system in the course of annealing. The results of the article can be used in further studies of the properties of the AI-TI-SI system, as well as in the creation of semiconductor structures taking into account properties such as high electrical conductivity, good processability, the absence of chemical components in the Al-Si system, chemical stability, and a tendency to electromigration, the possibility of short circuit, high diffusion mobility, low melting point, the inability to attach the wire by soldering. [ABSTRACT FROM AUTHOR]

The problems of molten zones formation and their subsequent migration over material surface are of interest from the viewpoint of developing novel technological methods of forming microelectronic structures. Such drops can be used as primary working elements of microlenses and reflectors, displays, weighers. The aim of this work was experimental studying processes of electromigration of molten silver- and aluminum-based inclusions over surfaces of germanium and aluminum semiconductor crystals. The issues of formation and motion of molten drops over the surfaces of silicon and germanium semiconductor crystals are considered within the framework of the electrocapillary approach. It is shown by an example of Ge-Ag and Si-Al systems that accelerated migration is related to the contribution of an electrocapillary component that relates surface tension force of melt drops to electric potential difference at the interface. The experiment consisted in applying metal grain to the surface of the samples and vacuuming the chamber where excessive pressure and the surface temperature were created. Migration of inclusions by powerful current pulses was initiated. An analysis of the effect of direct current on a drop of melt deposited on the surface of a crystalline matrix was made. An analysis of the droplet composition was carried out using the AES method, the results of which showed the relationship between silver and germanium concentrations. Quantitative evaluations are given for migration rates in systems under direct current flow as well as under pulsed current loads. During the experiment, it was found that the energy required to detach the droplet from the rigid matrix was not consumed. The value of the surface charge transfer density was estimated. The results of the work can be used to develop new technological methods for the formation of microelectronic structures and their use for practical purposes. [ABSTRACT FROM AUTHOR]

Oil production is a complex technological process that requires significant electricity consumption. The main electricity consumers in oil and gas production workshops are artificial lift facilities. Currently, among the objects of mechanized mining, installations of electric submersible pumps are widespread. When planning technological modes, it is necessary to be able to assess the change in the power consumption parameters when changing the technological process parameters. The paper proposes a typical replacement scheme for the electrical complex element. The power consumption calculation of electric submersible pump installations has been carried out. The error in the power consumption modeling results of electric submersible pump installations in comparison with the results of instrumental measurements is no more than 10%. The estimation of additional losses of electric energy caused by the influence of harmonics is carried out. The proposed technique makes it possible to estimate the power consumption of an electric submersible pump installation when changing the parameters of the technological process and equipment. The results of the work can be used for planning material support and optimization of warehouse stocks within the framework of integrated logistics support for the technological process of industrial enterprises. [ABSTRACT FROM AUTHOR]