The elastomagnetic parameters of a magnetic fluid kept by magnetic levitation in a tube placed horizontally in a strong magnetic field are measured, including the oscillation frequency, the ...ponderomotive and dynamic elasticity coefficients, the magnetization curve, and the magnetic field strength and its gradient. Results of calculations for the model of ponderomotive elasticity for the examined sample of the magnetic fluid corrected for the resistance of the moving viscous fluid are in good agreement with the experimental magnetization curve. The described method is of interest for a study of magnetophoresis, nanoparticle aggregations, viscosity, and their time dependences in magnetic colloids.
Based on the concept of mapping the free surface geometry of a weakly magnetic medium by the topography of isolines of the magnetic field strength magnitude, the shape of the free surface of a ...magnetic fluid is studied in the static state at two stages: the initial stage, where an annular magnet is moving toward the surface of the magnetic fluid column in a tube, and at the stage where the air cavity is pressed to the bottom. It is shown that the separation of bubbles from the air cavity occurs at the magnet axis in the immediate vicinity of the magnet symmetry plane. A method and an experimental setup are proposed to investigate possible electromagnetic indication of the size of air bubbles formed in the magnetic fluid. The results of an experimental study of bubble separation from an air cavity held in the magnetic fluid and compressed by the pondermotive forces of the magnetic field are discussed. The results may be of importance for designing a new technique for metering small gas shots to a reactor.
The dynamic demagnetizing factor
N
d
used to describe perturbation of magnetization of a magnetic fluid by a sound wave has been studied. Experimental
N
d
values obtained according to the proposed ...methodology have been compared with the results of a model theory based on the approximating function for bodies of cylindrical shape and oblate ellipsoids of rotation.
Purpose - to study the structural parameters of the magnetite particles surrounded by the surfactant in the various carrier liquids using SAXS and based on the magnetization curve obtained applying ...ballistic method. The samples of the magnetite magnetic fluid based on water, engine oil and kerosene were investigated in this paper. Methodology - three samples of magnetic fluid were chosen for studying. Samples No 1 and No 2 were obtained at the UNESCO department of "Energy Conservation and Renewable Energy Sources", Belarusian National Technical University. Sample No 3 was obtained in the Fundamental Scientific Research Laboratory of Applied Ferrohydrodynamics of Ivanovo State Power Engineering University. SAXS experiment was conducted using Anton Paar SAXSess mc2 analyzer at the Regional Centre of Nanotechnology of Southwest State University. Originality / value - The value of this work is to obtain new data on the physical parameters of the magnetic fluid samples. Findings - the derived surfactant shell width, which for the samples No 2, 3 was 1,8-1,9 nm, for the sample No 1 surfactant shell width was 3.5 nm, the excess of the calculated width of the surfactant layer can be explained due to the presence of a double layer of stabilizer.
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