in this paper, natural convection heat transfer over a vertical plate in a darcy porous medium saturated with a nanofluid subject to heat generation/absorption was theoretically studied. the governing partial differential equations were transformed to a set of ordinary differential equations using similarity transformations and solved using finite difference method. the influence of parametric ...

Multiple methods exist to measure the benthic flux of dissolved oxygen (DO), but many are limited by short deployments and provide only a snapshot processes occurring at sediment–water interface. The gradient (GF) method measures near bed gradients DO estimates eddy diffusivity from existing turbulence closure solve for flux. This study compares measurements seagrass, reef, sand environment wit...

Introduction: In radiation therapy with high-energy photon beams (E > 7 MeV) neutrons are generated mainly in LINACs head thorough (γ, n) interactions. These neutrons affect the shielding requirements in radiation therapy rooms. According to the protocol TG-34, photon absorbed dose of 10Gy can cause permanent damage to the pacemaker and the dose of 2Gy can make minor changes in...

a suitable emulgel formulation of piroxicam was prepared and its percutaneous permeation was investigated using wistar rat skin and diffusion cell technique. the concentrations of the drug in receptor phase of diffusion cells were measured using hplc method. the effect of three types of penetration enhancers (myrj 52, cineol and transcutol p) with different concentrations on transdermal permeat...

in this research, process asymmetric polyetherimide hollow fiber membranes using ethanol (0, 2 and 4 wt%) as non-solvent additive in the polymer dope via phase inversion method were fabricated. aqueous solution of 1-methyl-2-pyrrolidine (nmp) (90%) was applied as a bore fluid to avoid inner skin layer formation and water was used as the external coagulant. the morphology of fabricated membranes...

terms and conditions of current drinking water quality standards, including reducing the maximum arsenic concentration from 50 μgl-1 to 10 μgl-1 and predicted stricter standards in future, reveals the necessity for development of new technologies. this study aimed to prepare and evaluate a new nanocomposite membrane using graphene oxide (go) thin layer to remove arsenic (v) from water. to fabri...

this study focuses on the preparation and modification of a thin-film composite (tfc) hollow fiber polyamide membrane fabricated by the interfacial polymerization of piperazine (pip) and trimesoyl chloride (tmc) on a porous polysulfone substrate. the effects of triethylenetetramine (teta) and silica nanoparticles (sio2) contents in the aqueous phase (as the additives) on the morphology and perf...

Coronal magnetic flux ropes are generally considered to be the core structure of large-scale solar eruptions. Recent observations found that eruptions could initiated by a sequence "flux feeding," during which chromospheric fibrils rise upward from below, and merge with pre-existing prominence. Further theoretical study has confirmed feeding mechanism is efficient in causing eruption wrapped ba...