On thermal relaxation of magnetic fluid magnetization

doi:10.22364/mhd.50.3.1

A magnetic super lattice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126597 ◽

1987 ◽

Vol 45 ◽

pp. 360-361 ◽

Cited By ~ 1

Author(s):

M.D. Bentzon ◽

J. v. Wonterghem ◽

A. Thölén

Keyword(s):

Thermal Decomposition ◽

Oleic Acid ◽

Magnetic Fluid ◽

Magnetic Particles ◽

Carbon Film ◽

Thick Layer ◽

Amorphous Iron ◽

Super Lattice ◽

Carrier Liquid ◽

Median Diameter

We report on the oxidation of a magnetic fluid. The oxidation results in magnetic super lattice crystals. The “atoms” are hematite (α-Fe2O3) particles with a diameter ø = 6.9 nm and they are covered with a 1-2 nm thick layer of surfactant molecules.Magnetic fluids are homogeneous suspensions of small magnetic particles in a carrier liquid. To prevent agglomeration, the particles are coated with surfactant molecules. The magnetic fluid studied in this work was produced by thermal decomposition of Fe(CO)5 in Declin (carrier liquid) in the presence of oleic acid (surfactant). The magnetic particles consist of an amorphous iron-carbon alloy. For TEM investigation a droplet of the fluid was added to benzine and a carbon film on a copper net was immersed. When exposed to air the sample starts burning. The oxidation and electron irradiation transform the magnetic particles into hematite (α-Fe2O3) particles with a median diameter ø = 6.9 nm.

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Burgers fluid flow in perspective of Buongiorno’s model with improved heat and mass flux theory for stretching cylinder

The European Physical Journal Applied Physics ◽

10.1051/epjap/2020200286 ◽

2020 ◽

Vol 92 (3) ◽

pp. 31101

Author(s):

Zahoor Iqbal ◽

Masood Khan ◽

Awais Ahmed

Keyword(s):

Diffusion Process ◽

Mathematical Formulation ◽

Thermal Relaxation ◽

Mass Diffusion ◽

Stretching Cylinder ◽

Discussion Section ◽

Buongiorno’S Model ◽

Homotopy Analysis ◽

Burgers Fluid ◽

Diffusion Phenomena

In this study, an effort is made to model the thermal conduction and mass diffusion phenomena in perspective of Buongiorno’s model and Cattaneo-Christov theory for 2D flow of magnetized Burgers nanofluid due to stretching cylinder. Moreover, the impacts of Joule heating and heat source are also included to investigate the heat flow mechanism. Additionally, mass diffusion process in flow of nanofluid is examined by employing the influence of chemical reaction. Mathematical modelling of momentum, heat and mass diffusion equations is carried out in mathematical formulation section of the manuscript. Homotopy analysis method (HAM) in Wolfram Mathematica is utilized to analyze the effects of physical dimensionless constants on flow, temperature and solutal distributions of Burgers nanofluid. Graphical results are depicted and physically justified in results and discussion section. At the end of the manuscript the section of closing remarks is also included to highlight the main findings of this study. It is revealed that an escalation in thermal relaxation time constant leads to ascend the temperature curves of nanofluid. Additionally, depreciation is assessed in mass diffusion process due to escalating amount of thermophoretic force constant.

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Study on Cancer Treatment using Magnetic Fluid for Medicine and Induction Heating Device

IEEJ Transactions on Fundamentals and Materials ◽

10.1541/ieejfms.133.366 ◽

2013 ◽

Vol 133 (6) ◽

pp. 366-371 ◽

Cited By ~ 4

Author(s):

Hideo Nagae ◽

Sotoshi Yamada ◽

Yoshio Ikehata ◽

Satoshi Yagitani ◽

Isamu Nagano

Keyword(s):

Cancer Treatment ◽

Induction Heating ◽

Magnetic Fluid ◽

Heating Device

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Squeeze film performance in rough porous infinitely long parallel plates with porous matrix of variable film thickness under the presence of a magnetic fluid lubricant

SOP Transactions on Applied Mathematics ◽

10.15764/am.2014.02017 ◽

2014 ◽

Vol 1 (2) ◽

pp. 194-209

Author(s):

Rakesh Patel ◽

◽

Gunamani Deheri ◽

Pragna Vadher

Keyword(s):

Film Thickness ◽

Magnetic Fluid ◽

Porous Matrix ◽

Squeeze Film ◽

Parallel Plates ◽

Film Performance

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THERMOCONVECTIVE INSTABILITY OF A MAGNETIC FLUID WITH ALLOWANCE FOR MAGNETIC PERTURBATIONS

Proceeding of International Heat Transfer Conference 6 ◽

10.1615/ihtc6.2850 ◽

1978 ◽

Author(s):

V. A. Borodulya ◽

M. I. Pavlinov

Keyword(s):

Magnetic Fluid ◽

Magnetic Perturbations ◽

Thermoconvective Instability

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Correlating Blocking Temperatures in Single Molecule Magnets with Raman Relaxation

10.26434/chemrxiv.7067669 ◽

2018 ◽

Author(s):

Marcus J. Giansiracusa ◽

Andreas Kostopoulos ◽

George F. S. Whitehead ◽

David Collison ◽

Floriana Tuna ◽

...

Keyword(s):

Relaxation Time ◽

Single Molecule ◽

Energy Barrier ◽

Thermal Relaxation ◽

Relaxation Mechanism ◽

Blocking Temperature ◽

Single Molecule Magnets ◽

Single Molecule Magnet ◽

Key Parameter

We report a six coordinate DyIII single-molecule magnet (SMM) with an energy barrier of 1110 K for thermal relaxation of magnetization. The sample shows no retention of magnetization even at 2 K and this led us to find a good correlation between the blocking temperature and the Raman relaxation regime for SMMs. The key parameter is the relaxation time (𝜏switch) at the point where the Raman relaxation mechanism becomes more important than Orbach.

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