the efficiency of a collar in reducing the scour depth around circular and rectangular piers is studied at different flow intensities (ratio of upstream shear stress to sediment critical shear stress). rectangular piers aligned with the flow as well as skewed at 5º, 10º, 20º were examined. previous studies had shown that with collar the equilibrium time of scouring increases considerably. to re...

This study aims to investigate and optimize the effects of the main parameters including the particle size, gravity and magnetic separation combination, high gradient magnetic separation, magnetic field intensity, shaking table slope, washing water flow, and electrostatic separation upon the rare earth element (REE) recoveries from iron mine waste. The electron microprobe showed that high amoun...

objective: the present study aimed to compare prospective and retrospective memory impairment and attention deficit in people suffering from chronic low back pain with those cognitive functions in healthy subjects. furthermore, this study examines the relation between severity and duration of pain and prospective and retrospective memory impairment and attention deficit. methods: the research w...

background: chronic low back pain is among a wide spread musculoskeletal conditions that is related to disability with high economy cost. there are several treatment modalities for controlling chronic low back pain (clbp), among them high intensity laser therapy (hilt) and epidural blocks (eb) use more commonly. this study aimed to evaluate the benefits and hazards of each of these two methods....