This article presents the exact solutions of the velocity and temperature fields for a steady fully developed magnetohydrodynamic flow of a viscous incompressible and electrically conducting fluid between two horizontal concentric cylinders. Our study focuses on the influence of the Hartmann number, Brinkman number, Péclet number and inner radius on the fluid temperature field, entropy generati...

Laminar natural convection from an array of horizontal isothermal cylinders confined between two vertical walls, at low Rayleigh numbers, is investigated by theoretical and numerical methods. The height of the walls is kept constant, however, number of the cylinders and their spacing, the distance between the walls and Rayleigh number have been varied. The optimal spacing (confining walls) and ...

While equilibrium block-copolymer morphologies are dictated by energy-minimization effects, the semi-ordered states observed experimentally often depend on the details of ordering pathways and kinetics. Here, we explore reordering transitions in thin films of block-copolymer cylinder-forming polystyrene-block-poly(methyl methacrylate). We observe several transient states as films order towards ...

The objective of our paper is to start the theoretical investigation of the most commonly used mathematical model for natural convection in a horizontal annulus. First, one shows existence of solutions for the unsteady problem. Then, for any Prandtl number and inverse relative gap width, existence and stability of a steady solution is proved, provided that the Rayleigh number is sufficiently sm...

The gas delivered from a cylinder of Entonox (50% nitrous oxide and 50% oxygen) may not contain adequate quantities of oxygen if the cylinder has been cooled and then allowed to warm up in a vertical position.The composition of gas delivered from cylinders cooled to not lower than -40 degrees C. remains unaltered if the cylinders are rewarmed for 24 hours in a horizontal position at a temperatu...

The original protocol for implant prosthesis recommends the use of a gold framework for acrylic and ceramic prosthesis. However, due to its high cost, the use of alternative alloys is desired. This study compares the marginal accuracy of pre-made cylinders versus plastic cylinders cast with two different base metal casting alloys. Five samples each of (1) plastic cylinder cast in cobalt-chromiu...