Abstract: A process for producing middle distillates by hydrocracking a heavy distillate oil under middle pressure uses a hydrofining catalyst and a hydrocracking catalyst in series and once-through operation. The once-through volume conversion to 350.degree. C.--products is up to 80 vol. %. The yield and selectivity of middle distillates are greater than 40 wt % and less than 50 wt %, respectively. The process is particularly suited to treat heavy distillate oil having the nitrogen content of up to 1500 ppmw, the sulfur content of up to 3.5 wt % and dry point in the boiling range of higher than 500.degree. C. to produce the feed for reforming process, jet fuel, the low sulfur content diesel, the feed for catalytic cracker and the feed for producing ethylene.

Abstract: In a process for the cryogenic distillation of air in a distillation column system that contains at least one distillation column wherein the boil-up at the bottom of the distillation column producing the oxygen product is provided by condensing a stream whose nitrogen concentration is equal to or greater than that in the feed air stream, which comprises the steps of: (a) generating work energy which is in excess of the overall refrigeration demand of the distillation column system by at least one of the following three methods: (1) work expanding a first process stream with nitrogen content equal to or greater than that in the feed air and then condensing at least a portion of the expanded stream by latent heat exchange with at least one of the two liquids: (i) a liquid at an intermediate height in the distillation column producing oxygen product and (ii) one of the liquid feeds to this distillation column having an oxygen concentration equal to or preferably greater than the concentration of oxygen in the f

Abstract: A method of micromachining polytetrafluoroethylene by applying radiation light to the surface of polytetrafluoroethylene, includes the steps of: preparing a workpiece including a region made of polytetrafluoroethylene; preparing a mask having patterned areas substantially transmitting and not transmitting the radiation light; and applying the radiation light containing at least ultraviolet rays of a wavelength of 160 nm to a surface of the workpiece through the mask. Polytetrafluoroethylene can be microscopically processed, while obtaining a high aspect ratio and processing a large area with ease.