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Influence Of Nanoparticles Diameter On Structural Properties Of Magnetic Fluid In Magnetic Field

Abstract

The properties of magnetic fluids depend on the nanoparticle diameter, their concentration and the carrier liquid. The structural changes in magnetic fluids with different nanoparticle diameter based on transformer oils TECHNOL and MOGUL under the effect of a magnetic field and temperature were studied by acoustic spectroscopy. At a linear and jump changes of the magnetic field at various temperatures a continuous change was observed of acoustic attenuation caused by aggregation of the magnetic nanoparticles to structures. From the anisotropy of acoustic attenuation and using the Taketomi theory the basic parameters of the structures are calculated and the impact of nanoparticle diameters on the size of structures is confirmed.

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Nonlinear Convergence Algorithm: Structural Properties with Doubly Stochastic Quadratic Operators for Multi-Agent Systems

Abstract

This paper proposes nonlinear operator of extreme doubly stochastic quadratic operator (EDSQO) for convergence algorithm aimed at solving consensus problem (CP) of discrete-time for multi-agent systems (MAS) on n-dimensional simplex. The first part undertakes systematic review of consensus problems. Convergence was generated via extreme doubly stochastic quadratic operators (EDSQOs) in the other part. However, this work was able to formulate convergence algorithms from doubly stochastic matrices, majorization theory, graph theory and stochastic analysis. We develop two algorithms: 1) the nonlinear algorithm of extreme doubly stochastic quadratic operator (NLAEDSQO) to generate all the convergent EDSQOs and 2) the nonlinear convergence algorithm (NLCA) of EDSQOs to investigate the optimal consensus for MAS. Experimental evaluation on convergent of EDSQOs yielded an optimal consensus for MAS. Comparative analysis with the convergence of EDSQOs and DeGroot model were carried out. The comparison was based on the complexity of operators, number of iterations to converge and the time required for convergences. This research proposed algorithm on convergence which is faster than the DeGroot linear model.

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Dispersion of chromia films (eskolaite) in UV-VIS

. Kostyukov, T. V. Larina, N. A. Pakhomov, and V. N. Snytnikov, “Photoluminescence Properties of Microspherical Alumina-Chromium Catalyst”, Inorganic Materials: Applied Research , vol. 5(5), pp. 476–481, 2014. [24] G. K. B. Costa, A. López, I. C. S. Carvalho, O. Nakamura, N. Cella, L. P. Sosman, “Optical and structural properties of chromium impurities in niobium-gallium oxide”, Materials Chem. Phys. , vol. 148, pp. 764–771, 2014. [25] B. M. Weckhuysen, R. A. Schoonheydt, “Recent progress in diffuse reflectance spectroscopy of supported metal oxide catalysts

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Structural Evolution of Sputtered Indium Oxide Thin Films

Structural Evolution of Sputtered Indium Oxide Thin Films

The indium oxide thin films were deposited at room temperature by reactive magnetron sputtering in the mixture of oxygen and argon on silicon and oxidized silicon substrates. The influence of the oxygen flow in the reactive mixture and post-deposition annealing on the structural properties were investigated. The as deposited In2O3 films showed a dominating randomly oriented nanocrystalline structure of cubic In2O3. The grain size decreased with increasing oxygen concentration in the plasma. Annealing in reducing atmospheres (vacuum, nitrogen and argon), besides improving the crystallinity, led to a partial cubic to rhombohedral phase transition in the indium oxide films.

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Influence of SFRC Layer on Deflections and Cracks of Composite RC Slab

Abstract

This paper presents an experimental analysis of flexural capacity and deformability of structural concrete slabs prepared as composite members consisting of two concrete layers made of reinforced ordinary concrete (N) and fiber reinforced concrete (SFRC). The reinforced concrete composite slabs used in the tests were prepared in the dimensions of 600 x 1200 x 80 mm. The basis was composed of two layers consisting of SFRC, one as the top layer, and one as ordinary concrete. The results of the analysis confirm a significant improvement of structural properties of the composite slab in comparison to the slabs prepared wholly of ordinary concrete.

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Fabrication and characterization of Si/SiO2/TiO2/ZnO heterostructures from sputtered and oxidized Ti-film

Abstract

The present work reports the fabrication of p-Si/SiO2 /TiO2 and p-Si/SiO2 /TiO2 /ZnO heterostructures deposited by RF sputtering on p-Si substrate. The structural properties of the heterostructures were characterized by X-ray reflectivity and SIMS depth profiling. The electrical and optical properties of the heterostructures were investigated by I − V, C-V measurements and VIS spectroscopy, respectively. The measurements reveal that I − V characteristics in dark show semiconductor-insulator-semiconductor (SIS) structure properties. The I − V characteristics under illumination exhibit changes with significant increase of photocurrent due to photoassisted tunnelling and injection through SiO2 /TiO2 interlayer.

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On the Topological Properties of the Certain Neural Networks

Abstract

A topological index is a numeric quantity associated with a network or a graph that characterizes its whole structural properties. In [Javaid and Cao, Neural Computing and Applications, DOI 10.1007/s00521-017-2972-1], the various degree-based topological indices for the probabilistic neural networks are studied. We extend this study by considering the calculations of the other topological indices, and derive the analytical closed formulas for these new topological indices of the probabilistic neural network. Moreover, a comparative study using computer-based graphs has been carried out first time to clarify the nature of the computed topological descriptors for the probabilistic neural networks. Our results extend some known conclusions.

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Influence of Structural Parameters of Nonwoven Geotextiles on Separation and Filtration in Road Construction

Abstract

Nonwoven geotextiles are often used in road construction as a separation layer. They consist of the web of fibers with different orientations. The orientation of fibers has an important influence on physical and mechanical properties of nonwoven geotextiles. The production of nonwoven geotextiles is cheaper in comparison to woven or knitted fabrics which can also be used as separation geotextiles. The purpose of this research was to study the influence of structural properties of nonwoven geotextiles, namely the diameter of fibers and mass and thickness of nonwoven geotextiles, on their mechanical and hydraulic properties. Six types of nonwoven geotextiles were used in the research. They were produced by the drylaid process (carded) using mechanical bonding technique and also with the combination of mechanical and thermal bonding technique. The research confirmed that the bonding technique and structural properties significantly influence the separation and filtration properties of nonwoven geotextiles, such as opening size and water permeability. It was also found that there are no significant differences in mechanical properties, such as viscoelastic properties and compression creep, between the samples in the dry and wet conditions.

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Modification of TiN coatings by Ion Implantation

Abstract

The high-speed steel HS 6-5-2 cutting inserts coated with TiN were subjected to ion implantation with both silicon (dose 2×1017Si+/cm2) and silicon with nitrogen ions (dose (1+1)×1017(Si+ + N+)/cm2) on the subsurface layer of the rake face. Microhardness was examined before and after ion implantation. The composition and structural properties of the subsurface layer were examined by Glow Discharge Optical Emission Spectroscopy (GD-OES). The turning tests of 40H construction steel with the use of the cutting inserts implanted and non-implanted were performed. During the tests the two components of the net cutting force (the main cutting force Fc and feed force Ff) as well as the wear parameters VB on the major flankalong with the surface roughness (Ra) were measured. The implanted inserts exhibited higher durability compared to non-implanted ones.

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Probabilistic Analysis for Estimation of the Initiation Time of Corrosion

Abstract

In this paper, a probabilistic study on durability concrete was carried out. In such a design, initiation time of corrosion must be expressed as a mathematical model using Fick’s second law and the statistical distributions properties of theirs parameters was included in this model. The scatter both in the environmental exposure conditions and structural properties was considered as random fields in the mathematical model with a probabilistic design. The main objective of this study is predicted initiation time of corrosion of concrete structures in chloride containing environments. This probabilistic study is developed using Monte Carlo simulation to determine the contribution of each input parameters and the statistical parameters of the random variables on the probability distribution functions of the initiation time of corrosion. Also, a comparison study was carried out to analyze the impact of the probability distribution on the response (the initiation time of corrosion).

Open access