Abstract: The present invention provides a column endpiece for a chromatography column. The column endpiece includes a base part, an extension piece for a discharge tube, and a frit. The frit produces a pressure drop per unit length that is at least twice as great as the pressure drop per unit length created in the sorbent packing when the eluent is flowing through.

Abstract: An internal combustion piston engine comprises a cylinder with a cylinder bore therein; a cylinder head mounted on said cylinder; a piston reciprocably movable in said cylinder bore, and a main combustion chamber formed between the cylinder head and the piston. At least one secondary combustion chamber is arranged to be connected at least temporarily to the main combustion chamber via at least one connecting channel whereby different compressions and hence different pressure rises occur during the compression stroke or the expansion stroke of the piston in the main combustion chamber or in the secondary combustion chamber. Control means are arranged in the zone of the connecting channel to enable the flow of the gases, which are under a higher pressure, from the main combustion chamber into the secondary combustion chamber or vice versa, to generate velocity fields which improve the turbulence, in particular in the quench zones of the main combustion chamber, and hence improve the combustion.

Abstract: A plate having a plurality of small openings therein mounted to the exit t of a recoilless weapon for reducing the depth of penetration of the disturbed gas field without significantly effecting the recoil reduction characteristics of the weapon.