Abstract: A lift for moving a wheelchair over a stairway includes a ramp, a wheelchair supporting platform and a mechanism for operating the platform over the ramp. When the lift is inoperative, the wheelchair supporting platform can be removed from the ramp and the ramp can be stored such that it does not intrude into the stairway and the operating mechanism is inaccessible.

Abstract: A closure for the cab of an aircraft passenger loading bridge comprises a bellows-type curtain frame which includes an outer inverted U-shaped frame having it legs pivoted to the platform for lateral movement and having a pair of power actuator assemblies which are articulated to permit lateral movement of the outer end of the frame to conform to any aircraft contour.

Abstract: An apparatus and method for (1) reducing agglomerated masses of tar sand and (2) recovering as a bituminous product the bituminous matrix material therefrom. The apparatus includes a vessel which is divided into an attrition zone enclosed by a screen member, a sand separation zone and a product recovery zone. The vessel accommodates liquid which is, advantageously, a solvent into which the agglomerated masses of tar sands are introduced. The liquid is impelled vigorously upwardly into the attrition zone to create a high shear environment by which the tar sand masses are reduced by attrition into sand particles coated with the bituminous matrix material of the tar sand. The separated grains of sand are also stripped of the bituminous product by the high shear environment. The cleansed sand passes through the screen member surrounding the attrition zone into the sand separation zone. The liquid and the bituminous product removed from the sand passes to the product recovery zone.