Nanotechnology Research and Practice

Number 2 (6), 2015

60-67
Effects of the Magnetic Flux and the Rashba and the Dresselhaus Interactions on the Tunneling Nanoscale Magnetoresistance of a Three-Terminal Quantum Ring

Authors: Mostafa Behtouei, Amin Maleki Sheikh Abadi

Abstract

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In this paper we investigated the effect of tunneling magnetoresistance in one-dimensional three-terminal mesoscopic ring in the presence of the magnetic flux and the Rashba spin-orbit interaction (RSOI) and the Dresselhaus spin-orbit interaction (DSOI). We calculated the current flow in this structure based on the Landauer-Buttiker formalism and a generalized Green’s function technique for parallel and antiparallel spin orientations in ferromagnetic electrodes. Calculations show that the tunneling magnetoresistance increases with the strength of the magnetization. The required conditions for reach the maximum values of the tunneling magnetoresistance are also calculated.

68-71
Investigation of Dynamics of Nanofluid

Authors: Abbas Salimi Fard, Farshad Farahbod

Abstract

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Number of views: 538

Experimental work is held to investigate how nanoparticles affect the hydrodynamic properties of the fluid. Nano zinc oxide (ZnO) particles with different diameters are produced with using the ultrasonic method using different time duration. In this research the thermal conductivity enhancement, the viscosity changes, heat capacity, shear rate and density of nanofluid are compared with those ones in water base fluid.

72-80
Microdispersed Colloid Silver Nanoparticles in Bionanotechnology

Authors: Ignat Ignatov, Oleg Mosin

Abstract

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Number of views: 636

In this review article are studied the methods for preparation of micro dispersed colloid silver nanoparticles and scopes of their practical application in nano-industry, bionanotechnology, medicine and allied industries, including water processing and water purification techniques. The mechanisms of bactericidal influence of colloid silver on a microbial cell are discussed from the point of view of absorptive, electrostatic, enzyme and mutagen theories. Silver exerts both bactericidal and bacteriostatic effect against more than 500 species of microorganisms. The effect of bacterial destruction by silver is 1500 times more than the same concentration of phenol and 3,5 times more than the action of mercuric chloride. It is demonstrated that effects of colloid silver are defined by the concentration, the sizes of micro dispersed nanoparticles and their stability in water solutions. The silver nanoparticles in their turn may be prepared by using various physico-chemical, biochemical and biotechnological methods.

81-92
Magnetohydrodynamic Cell for Magnetic Water Treatment

Authors: Oleg Mosin, Ignat Ignatov

Abstract

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Number of views: 492

This review article outlines an overview of new trends and modern approaches for practical implementation of magnetic water treatment to eliminate scaling salts (carbonate, chloride and sulfate salts of Ca2+, Mg2+, Fe2+ and Fe3+ cations) in power heat-exchanger devices and pipe lines. The principles of physical effects of the magnetic field on H2O molecules as well as the parameters of physico-chemical processes occurring in water and the behavior of the dissolved in water scaling salts subjected to the magnetic treatment are discussed. It is demonstrated that the effect of the magnetic field on water is a complex multifactorial phenomenon resulted in changes of the structure of hydrated ions as well as the physico-chemical properties and behavior of dissolved inorganic salts, changes in the rate of electrochemical coagulation and aggregate stability (clumping and consolidation), formation of multiple nucleation sites on the particles of fine dispersed precipitate consisting of crystals of substantially uniform size. There are also submitted data on constructive features of various magnetic water treatment devices produced by domestic industry, based on the permanent magnets and electromagnets (solenoids), such as hydro magnetic systems (HMS), magnetic transducers (MT) and magnetic activators (MA) of water. It was estimated the efficiency of using the various magnetic water treatment devices in water treatment technologies.