Abstract: A process for the processing of an undried particulate polymer or polymer mixture by means of a single- or multiscrew extruder comprising a barrel comprising one or more screws, a feed section intended for the polymer and provided on the barrel and, provided on the barrel, a melting region in which the polymer or polymer mixture melts, where the undried polymer or polymer mixture introduced by way of the feed section into the barrel is devolatilized in at least one vacuum devolatilization region downstream of the feed section and upstream of the melting region in the barrel.

Abstract: The ultrafiltration rate of a blood purification apparatus is controlled by a fuzzy control device in dependence on the patient's (16) blood pressure measured by a blood pressure monitor (24). For this purpose the blood pressure (P), a short-term blood pressure trend value (TRK) and a long-term blood pressure trend value (TRL) are fed as input variables for the fuzzy controller to the control device (23). The ultrafiltration rate (UFR) is determined by the volumetric ultrafiltration pump (36). According to the patient's (16) blood pressure situation a prestored profile of the ultrafiltration rate is modified. This avoids the necessity of an additional infusion to prevent too strong a blood pressure decrease.

Abstract: A process and a degassing unit for the degassing of plastic melt in a screw extruder in which a surface of the degassing unit facing the screws of the extruder are heated to prevent deposition of entrained plastic particles, particularly at the corners or edges of the degassing unit. Prior to the commencement of the treatment process, the degassing unit is heated to a temperature which is at least as high as the melting point of the plastic to be treated. Heating can be effected by conveying a heating medium through a channel in the degassing unit located in proximity to the surface facing the extrusion screws and especially the corner or edge regions.

Abstract: A pump hose for a peristaltic pump consists of two arcuate portions that merge along kink lines so that the undeformed hose lumen has the cross-sectional shape of a convex lens. The joinings of the arcuate portions are joined by outwardly extending ribs. When the hose is pressed, only minor squeezing occurs at the joinings. The hose has a considerably improved squeezing and restoring behavior. The ribs prevent an excessive squeezing.

Abstract: The removal of impurities, for example monomeric low-molecular substances, solvents or the like, from polymeric synthetic plastics materials takes place by the admixture of extraction gas in a first extruder in a supercritical state. The mixture is transferred to a second extruder where, in a first separating zone, and by a counter-current method, it is cleansed of the major part of the extraction gas containing the impurities, this being passed through a discharge orifice. Separation of any residue takes place in a vacuum zone on the downstream side. The high pressure in the first extruder is maintained by a counter-pressure valve in the connecting pipe between the first and second extruders. By the separation of contaminated extraction gas from molten synthetic plastics material in a closed space, namely the second extruder, it is possible to achieve an ordered dissipation of extraction gas on the one hand and molten synthetic plastics material on the other hand.

Abstract: A pressure sensor for determining the pressure of a medium in an elastic hose section. A pressure member acts on a unilaterally fixed bar carrying an influencing member at its free end. This influencing member is a core of a coil arrangement, the position of the core changing the frequencies of the oscillator coils. Numerous pressure values are received at regular intervals and, subsequently, a representative pressure value is obtained by averaging.

Abstract: Processes are described for the selective extracorporeal precipitation of low density lipoproteins or beta-lipoproteins from whole serum or plasma, wherein a treating agent comprising heparin or a polyanion, such as dextran sulfate or sodium-phosphorus tungstate, in a buffer is added to the whole serum or plasma and the beta-llipoprotein-complex which thereupon forms with the treating agent is precipitated at the isoelectric point at a pH value in the range of from about 5.05 to about 5.25, and is then separated. Optionally, the precipitate or respecively the filtrate is further analyzed for diagnostic purposes. When heparin is employed, the process may be employed therapeutically.Apparatus is described for the continuous therapeutic practice of such a process, employing heparin, including means for flushing to reduce clogging of the filter employed to separate the precipitated lipoprotein-complex.

Abstract: A dialytic apparatus for single-needle dialysis comprises a first pump in the artery conduit, which first pump in the first phase conveys blood from the patient into the expansion chamber while the vein conduit is shut off. At the same time, the second pump transports blood from the expansion chamber to the dialyzer. This regulation is performed in dependence from the pressure in the vein conduit so that the pressure decrease caused by ultrafiltration is counterbalanced. In the second phase, the first pump stands still and closes the artery conduit while the second pump conveys blood out of the expansion chamber to the dialyzer at a constant rate.

Abstract: The dialysis equipment has a dialysate path connectable to a dialysate source 1, and contains a feed pump 6, a dialyzer 10, and a controlled suction pump 13. During the operative phase, this dialysate path is traversed by the dialysate with a constant negative pressure being maintained in the dialysate chamber 101 of the dialyzer 10 relative to the blood chamber 102. In a subsequent measuring phase, the dialysate path is cut off from the dialysate source 1 and from a drain 15 via a valve device 2, 14. The same negative pressure is maintained in the dialysate chamber 101 as in the operative phase. The ultrafiltrate passing from the blood chamber 102 into the dialysate chamber 101 during the measuring phase causes the filling of a volume measuring device 5.

Abstract: An apparatus for hemodiafiltration that maintains the blood concentration of the patient relatively constant. A pump is connected to a branch off the external flow path of the dialysator which pumps fluid to the circulation system of the patient to compensate for the patient's fluid loss through the hemodiafilter membrane. A suction pump which affects the transmembrane pressure across the hemodiafilter membrane is controlled to achieve the desired filtrate flow necessary to balance the return flow to the patient.

Abstract: A dialysis apparatus utilizes an expansion chamber in parallel with a pump from which the chamber receives blood via a valve. During the return flow phase the pump rotates in the same direction; but, the valve is closed and a valve at the chamber outlet is opened. The pump draws blood from the chamber and transports it to a dialyzer. A control device regulates the pump and valves depending on the time integral of the pump delivery. In each phase, blood is transported until the chamber has received or discharged a predetermined volume. The pump speed is variable during operation.