The presence of particles in liquid-solid fluidized beds enhances the bed heat transfer, because the movement of the particles leads to an increased turbulence in the system. Moreover, the violent movement of the particles has a positive effect on fouling of the heat transfer surface. The aim of this investigation was to perform systematic measurements of bed voidage and heat transfer coeff...

The sparse tall grass significantly affects the heat and moisture exchange in the lower atmosphere through the turbulent transfer coefficient inside its environment. Common approaches for calculation of turbulent transfer coefficient inside the tall grass environment are based on the assumption that it depends either on wind speed or mixing length inside the canopy. In this paper we suggested a...

We investigated blood-brain barrier permeability in 2-3-week-old anesthetized pigs during and after cardiopulmonary resuscitation. We assessed permeability by tissue uptake of radiolabeled aminoisobutyric acid, after correcting for plasma counts in tissue with radiolabeled inulin. Among 14 regions examined, the transfer coefficient of aminoisobutyric acid in nonischemic control animals ranged f...

Nomenclature a = stoichiometric coefficient av = surface-to-volume ratio C;, Cb; = surface and bulk concentration, vol % Da = Damkohler number Eif R = activation energy, K F = steady-state function h = heat-transfer coefficient K, = adsorption equilibrium coefficient k, k0 = reaction rate constant and preexponential factor, respectively kc = mass-transfer coefficient l = apparent reaction order...

This paper is Part II of a two-part study devoted to measurement and prediction of the saturated flow boiling heat transfer coefficient in water-cooled micro-channel heat sinks. Part I discussed the experimental findings from the study, and identified unique aspects of flow boiling in micro-channels such as abrupt transition to the annular flow regime near the point of zero thermodynamic equili...

Wind-driven surficial oxygen transfer into stationary water bodies has become increasingly important because the fate of many pollutants in these water bodies is strongly influenced by oxygen mass transfer. There are many existing correlations that can be used for predicting wind-driven surficial oxygen transfer; however, the actual prediction has been difficult because there are large variatio...

The condensation heat transfer coefficient of R134a was experimentally studied inside two smooth and four micro-fin tubes. The working conditions and structural parameters of the test tubes were selected as the influencing factors, and the experiment was conducted under mass velocities of 400–1100 kg·m−2·s−1, condensation temperatures of 35–45 ◦C and water-testing Reynolds numbers of 8000–22,00...

in the present work, graphene was synthesized by chemical vapor deposition (cvd) method. the structure of graphene was then confirmed by x-ray diffraction (xrd) and scanning electron microscope (tem) images. after that, mixed acid method (h2so4/hno3) was used to make the structure of synthesized graphenehydrophilic. in this method, carboxylate and hydroxide groups were linked to the edges of gr...

The kinetics of calcination of a high calcium type of limestone was studied. Ukpilla limestone found in the central region of Nigeria was studied. The limestone composition shows that the limestone has 51.29% calcium oxide and 41.53% loss on ignition and magnesium oxide content of 2.23%. The following parameters were determined; diffusion coefficient of lime layer, and mass transfer coefficient...