The segregation of large spheres in a granular bed under vertical vibrations is studied. In our experiments, we systematically measure rise times as a function of density, diameter, and depth, for two different sinusoidal excitations. The measurements reveal that, at low frequencies, inertia and convection are the only mechanisms behind segregation. Inertia (convection) dominates when the relat...

Pulses of fine sediment in gravel-bedded rivers can cause extensive fine sediment infiltration (FSI) into void spaces in coarse bed material, potentially altering river morphodynamics and aquatic ecosystems. Previous work suggests a conceptual model of FSI whereby FSI occurs to a limited depth as a function of the relative grain size of bed sediment compared with infiltrating sediment and is in...

BACKGROUND The biomechanical properties of the cornea should be taken into account in the refractive procedure in order to perform refractive surgery more accurately. The effects of the ablation depth and repair time on the elastic modulus of the rabbit cornea after laser in situ keratomileusis (LASIK) are still unclear. METHODS In this study, LASIK was performed on New Zealand rabbits with d...

No study has examined the effectiveness of backboards and air deflation for achieving adequate chest compression (CC) depth on air mattresses with the typical configurations seen in intensive care units. To determine this efficacy, we measured mattress compression depth (MCD, mm) on these surfaces using dual accelerometers. Eight cardiopulmonary resuscitation providers performed CCs on manikins...

the study of flow in compound channels with vegetated floodplains is essential to assessing the development of the stage-discharge relationship and sediment and pollutant transport. the present study experimentally investigated mean flow and turbulence characteristics in a prismatic compound channel. the experimental program consisted of vegetated and non-vegetated floodplains with different re...

grade control structures are hydraulic structures used to stabilize a river bed. scour downstream of this structure is the main cause of its failure. studies have developed numerous empirical relations for scour depth prediction that designers must choose between to decide the most effective equation for a specific application. this study tested the condition of submerged jets over beds of sedi...

Fixed-bed sorption process can be very effective at removing arsenic from contaminated groundwater. In this study, a continuous operation was demonstrated for the removal of both arsenite [As(III)] and arsenate [As(V)] from aqueous media in a column packed with nanoscale iron–manganese binary oxides (NIM). Treatment performance of the sorbent was quantified by upflow column experiments at diffe...

Shallow particulate beds on surfaces vibrating at ca. 25 Hz and an amplitude of a few millimetres display several states, in order of increasing bed depth: two ‘Newtonian states’ in which freely bouncing particles obey simple New tonian mechanics; a ‘coherentexpanded (C-E) state’ in which particles move together in loosely organized packets to form a turbulent shallow layer; and a ‘coherent-con...

Breaching of earthen or sandy dams/dunes by overtopping flow and waves is a complicated process with strong, unsteady flow, high sediment transport, and rapid bed changes in which the interactions between flow and morphology should not be ignored. This study presents a depth-averaged two-dimensional (2D) coupled flow and sediment transport model to investigate the flow and breaching processes w...