Abstract: A pixelated X-ray conversion screen includes a metal aperture sheet having a pixel hole filled with a scintillator material, wherein an area of the pixel hole is equal to or less than about 0.25 mm2.

Abstract: A handguard assembly includes a first handguard including an interior surface and an exterior surface. The interior surface faces toward an associated barrel of an associated firearm and the exterior surface faces away from the associated barrel. The first handguard extends between a breech end of the first handguard and a muzzle end of the first handguard so as to define a longitudinal axis and a first handguard length. The handguard assembly also includes an adapter radially surrounding an associated barrel nut along the longitudinal axis. The adapter is longitudinally disposed between the first handguard and an associated receiver of the associated firearm.

Abstract: A handguard assembly includes a handguard and a key. The handguard includes a first ear with a first ear inner surface and a second ear with a second ear inner surface that cooperate to define a slot that extends in a longitudinal direction. The key is received in the handguard and includes a main body with an interior side and an exterior side that face in opposite directions from one another so as to define a main body depth and a first projection extending from the interior side of the main body so as to define a first projection depth. The first projection includes a first projection contact face that contacts the second ear inner surface when at least one fastener compresses the slot so as to prevent overtightening of the handguard.

Abstract: The invention is the use of standing waves to generate a well log. By measuring changes in energy dissipation from the standing wave along the well-bore, the formation may be evaluated for permeability variations may be determined. Variations in the tube wave velocity may be determined from variations in the frequency of a standing tube wave having a selected wave length. Shear wave velocity of the surrounding formation may be determined from the tube wave velocity.