Derivation of ferrofluid lubrication equation for slider bearings with variable magnetic field and rotations of the carrier liquid as well as magnetic particles
Based on the Shliomis model for ferrofluid flow and continuity equation, modified Reynolds equation for the study of lubrication of different slider bearings, is derived by considering the effects of oblique radially variable magnetic field and squeeze velocity. The Shliomis model is important because it includes the effects of rotations of the carrier liquid as well as magnetic particles. The variable magnetic field is important because of its advantage of generating maximum field at the required active contact zone. Using Reynolds equation, expressions for dimensionless load-carrying capacity, frictional force, coefficient of friction and center of pressure are obtained. Using these expressions, results for different slider bearings are computed for different parameters and compared.
Delipidation of liver homogenates, using an organic solvent system which does not denature proteins, increases measurable ferritin by 25-33%, compared to ferritin concentrations by standard heat supernatant assays. When applied to polyacrylamide gradient gels, lipid-associated ferritin does not enter the gel but after delipidation, this ferritin co-migrates with cytosolic ferritin and with purified liver ferritin. The biological significance of the association of ferritin with lipid has yet to be examined.