Abstract: In a mining machine (1) designed for underground operation, for example for cutting coal seams, and being equipped with a removal conveyor means taking up the heap of debris in front of the mine face and transferring this heap of debris to a removal conveyor plant (18) arranged behind the mining machine (1), there is interpositioned, separately from the mining machine, between the mining machine (1) and the removal conveyor plant (18) a crushing aggregate (2) comprising its own travel drive and being movable on a chassis in particular being equipped it caterpillars (27). The crushing aggregate (2) comprises a receiving chute (11) provided on a frame (25), a conveyor (12) starting from this receiving chute and extending with its discharge end beyond said frame and at least one crusher roll (13) within the area between the receiving chute (11) and the discharge end (15) of the conveyor (12).

Abstract: Optionally active 13,14-dehydro-11-deoxy prostaglandins useful in inhibiting gastric secretions and as anti-asmthmatic agents are disclosed.

Abstract: A method for detecting the presence in water of substances which are rapidly oxidized by ozone with the emission of quanta of visible light, which method comprises contacting the water with ozone and detecting the light quanta emitted.

Abstract: Aromatic polyetherketones and/or sulphones are produced by heating a halophenol of formula ##STR1## where X = halogen and is ortho or para to Q; Q = --CO-- or --SO.sub.2 --, Ar = an aromatic radical, with about 1/2 mole of a granular alkali metal carbonate per mole of halophenol in the presence of N-methyl pyrrolidone, dimethyl sulphone or an aromatic sulphone solvent at 200.degree.-400.degree. C.

Abstract: Cooling an extruding thermoplastic tube by feeding the tube adjacent a cooling surface, maintaining a sheath of heat-transfer fluid between the tube and surface and preferentially cooling at least a selected area of the tube by transversely displacing the tube to decrease the thickness of the sheath between the selected area and the cooling surface. The invention is particularly suitable, for the production of thermoplastic films by orienting a cast tubular extrudate which has been cooled by means of an internal mandrel.