knowledge of the warming or cooling effects induced by asphalt or grass covered areas, may improve our understanding of how thermal stress or thermal comfort is created for workers who have to work outdoors for long hours in warm seasons. for this purpose a field measurements were carried out to know the cooling and warming effects of two adjacent areas, one covered with grass and the other wit...

We report the dramatic effect of applied pressure and magnetic field on the layered intermetallic compound Pr(0.5)Y(0.5)Mn(2)Ge(2). In the absence of pressure or magnetic field this compound displays interplanar ferromagnetism at room temperature and undergoes an isostructural first order magnetic transition (FOMT) to an antiferromagnetic state below 158 K, followed by another FOMT at 50 K due ...

The instabilities of thermocapillary liquid layers with two free surfaces are examined by linear stability analysis. surface tension is big enough to keep the non-deformable. effect vertical temperature difference between interfaces (Q) considered. critical parameters preferred modes determined, which depend on Prandtl number (Pr) and Biot (Bi). When Q=0, oblique wave at small Pr streamwise lar...

The responses to external excitations in thermocapillary liquid layers are investigated by non-modal stability theory. maximum amplification of input signals is measured a response function depending on the perturbation velocity and temperature. There can be rather large amplifications subcritical flows at both small Prandtl numbers (Pr). For Pr, increases significantly with Reynolds number (R)...

The effect of thermophoresis particle deposition on unsteady free convective, heat and mass transfer in a viscoelastic fluid along a semiinfinite vertical plate is investigated. The Walters-B liquid model is employed to simulate medical creams and other rheological liquids encountered in biotechnology and chemical engineering. The dimensionless unsteady, coupled and non-linear partial different...

This paper presents and discusses the numerical simulations of transient laminar natural convection cooling of high Prandtl number fluids in cubical cavities, in which the six walls of the cavity are subjected to a step change in temperature. The effect of the fluid Prandtl number on the heat transfer coefficient is studied for three different fluids (Golden Syrup, Glycerin and Glycerin-water s...

In this paper the effect of Viscoelastic fluid flow past an infinite plate with heat dissipation is investigated. The dimensionless governing equations are solved using perturbation technique. The analytical results for velocity and temperature and there different parameters such as Prandtl number, Eckert number and Viscoelastic parameter number are studied. It is observed that the velocity dec...

Crystals of K2Y0.999Pr0.001F5 and K2Y0.98Pr0.02F5 were grown by the hydrothermal synthesis technique. The luminescent properties are investigated by performing low-temperature selective excitation. With laser excitation set at 583.7 nm, blue emission from P0 level of Pr 3+ ions in K2YF5:Pr is observed and analyzed via an up-conversion model. Crystal field calculation of Pr ions in K2YF5 has bee...

PROOF. It suffices, by standard facts about probability measure, to prove the claim for cylinders C(w′) ⊆ ′, where w′ = w0, . . . wk. We use induction on k. The base case (k = 0) follows from Lemma 7. Namely, C( ) = ′, and ρ−1( ′) = \ ρ−1( ). Thus Pr (ρ−1( ′)) = 1 − Pr (ρ−1( )) = 1. For the induction step, suppose that the claim holds for the prefix w′ = w0w1 . . . wk. Let D[w′] = ρ−1(C(w′)). D...

asphaltenes are the n-pentane or n-heptane insoluble fractions of crude oil that remain in solution under reservoir temperature and pressure conditions. they are destabilized and start to precipitate when the pressure, temperature and/or composition changes occur during primary production. the precipitated asphaltene particles will then grow in size and may start to deposit onto the production ...