Abstract: A selectively permeable hollow fiber membrane for blood dialysis consisting substantially of a cellulose derivative, which has at least a dense layer on the innermost side and a porous layer of greater void percentage on the outside, and a process for producing the selectively permeable hollow fiber membrane consisting substantially of a cellulose derivative, which comprises extruding a spinning solution containing a polymer consisting substantially of a cellulose derivative dissolved in an organic solvent, from an annular slit into a filamentous form, while simultaneously introducing a core material solution with a water content of at least 50 wt % into the extruded filamentous body, and then immersing the filamentous body into a coagulating solution after passing it through a gas.

Abstract: A quality control system in a material processing mill. The mill may include several different processing machines for performing several different processing steps to produce several different intermediate products. Each processing machine is provided with a sub-processor for monitoring production information associated with the processing machine and quality information associated with the intermediate product produced by the processing machine. The quality and production information from the various sub-processors are directed to a main processor, which records a history of the processing of the various intermediate products.

Abstract: A method for making hollow fibers having a selective permeability, wherein a majority of the hollow fibers each has on the periphery thereof 1 to 10 fins extending in the longitudinal direction, and the occupancy ratio y of the sections, defined by the peripheries, of all the hollow fibers exclusive of the fin portions in the hollow fiber bundle to the section, vertical to the axial direction of the hollow fiber bundle, of the inner wall of the shell is within a range defined by the following formula (I):41-3.1.sqroot..alpha.x.ltoreq.y.ltoreq.61-3.1.sqroot..alpha.x (I)wherein x stands for the average fin number per hollow fiber in the hollow fiber bundle, and .alpha. indicates the ratio H/d of the average fin height H (.mu.)in the hollow fiber bundle to the average outer diameter d (.mu.) of the hollow fibers exclusive of the fin portions.

Abstract: Disclosed is a fluid separator comprising a shell filled with a bundle of hollow fibers having a selective permeability, wherein a majority of the hollow fibers each has on the periphery thereof 1 to 10 fins extending in the longitudinal direction, and the occupancy ratio y of the sections, defined by the peripheries, of all the hollow fibers exclusive of the fin portions in the hollow fiber bundle to the section, vertical to the axial direction of the hollow fiber bundle, of the inner wall of the shell is within a range defined by the following formula (I): ##EQU1## wherein x stands for the average fin number per hollow fiber in the hollow fiber bundle, and .alpha. indicates the ratio H/d of the average fin height H(.mu.) in the hollow fiber bundle to the average outer diameter d (.mu.) of the hollow fibers exclusive of the fin portions.

Abstract: Irradiation treatment of an effluent gas by means of electron beams can be carried out efficiently by controlling the velocity and the velocity distribution of the stream of gas when it passes through a zone to be irradiated. Such control can be effected conveniently according to the present invention by first introducing the stream of gas into a velocity reduction zone and then leading it to a velocity re-accelerating and velocity distribution adjusting zone immediately before the thus adjusted stream of gas reaches the zone to be irradiated.An apparatus suitable for practicing such process is also disclosed.

Abstract: Irradiation treatment of an effluent gas by means of electron beams can be carried out efficiently by controlling the velocity and the velocity distribution of the stream of gas when it passes through a zone to be irradiated. Such control can be effected conveniently according to the present invention by first introducing the stream of gas into a velocity reduction zone and then leading it to a velocity re-accelerating and velocity distribution adjusting zone immediately before the thus adjusted stream of gas reaches the zone to be irradiated.An apparatus suitable for practicing such process is also disclosed.