Abstract: The present invention is directed to poly-.alpha.-olefin/polyurethane block copolymers which are prepared by reactingA) isocyanate-reactive functionalized poly-(C.sub.2 -C.sub.10 -.alpha.-olefins) having a number average molecular weight M.sub.w of about 1000 to 350,000,B) polyisocyanates, isocyanate prepolymers or modified polyisocyanates, and, optionally,C) isocyanate-reactive synthesis units containing Zerewitinoff-active hydrogen atoms and having a molecular weight of 400 to about 5000 and, optionally,D) low molecular weight isocyanate-reactive chain extending agents having a molecular weight of 32 to 399.The present invention is also directed to this process for preparing the poly-.alpha.-olefin/polyurethane block copolymers and to their use as polymer dispersants for the production of polymer blends, as primers or modifiers or for the production of moldings or coatings.

Abstract: Reactive systems consisting of organic polyisocyanates, organic polyepoxides, polymer modifiers, special catalysts and optionally other auxiliary agents and additives.

Abstract: A continuous-flow steam generator includes a vertical gas flue for connection to an outlet conduit of an apparatus emitting hot gas, such as a gas turbine. An evaporator heating surface in the vertical gas flue has an inlet header, an outlet header and tubes connected between the inlet and outlet headers. The tubes form an upper tube segment having an upper segment end and a lower segment end as well as a lower tube segment having an upper segment end and a lower segment end. The upper segment end of the upper tube segment merges with the upper segment end of the lower tube segment.

Abstract: The invention relates to blends of polyarylene sulfides, epoxides, anhydrides, glass fibers and optionally other fillers. The blends are distinguished by good mechanical properties.

Abstract: The present invention relates to a reaction resin composition comprising a mixture of polyisocyanates, epoxides, and amine catalysts of the formula ##STR1## wherein A is independently alkylene, alkenylene, alkynylene, alkylidene, cycloalkylene, or aralkenylene; m is an integer of from 0 to 30; R.sup.1, R.sup.2 and R.sup.3 are independently optionally substituted aralkyl or polyaralkyl; and R.sup.4 is alkyl, alkenyl, alkynyl, cycloalkyl, or optionally substituted aralkyl or polyaryalkyl.

Abstract: A steam generator includes a gas flue having burners for fossil fuel, a gas-tight tube wall with tubes, inlet and outlet headers connected to the tubes, the outlet header being at a higher level than the inlet header, and a down pipe outside the tube wall connecting the outlet to the inlet header. A steam line is connected to the outlet header and at least one heating surface is connected downstream of the outlet header in the steam line. A feedwater line is connected to the gas flue and an economizer is connected upstream of the gas flue in the feedwater line.

Abstract: The present invention is directed to aqueous solutions or dispersions of cationically modified polyurethanes, characterized in that the dissolved or dispersed polyurethanes(i) contain about 2 to 200 milliequivalents of incorporated ammonium groups per 100 g of solids content,(ii) contain 0 to about 25% by weight of ethylene oxide units within terminal or lateral polyether chains and(iii) contain at least 1.3% by weight, calculated as SiO.sub.3 (molecular weight=76), of built-in structural units corresponding to the formula ##STR1## wherein R', R" and R"' may be the same or different and represent hydrogen or alkyl groups containing 1 to 4 carbon atoms,the total quantity of hydrophilic structural units (i) and (ii) being sufficient to ensure the solubility or dispersibility of the polyurethanes in water and the solutions or dispersions having a pH value of 3 to 6.

Abstract: This invention relates to thermoplastic moulding compositions of PVC and poly-.alpha.-olefine/polyurethane block copolymers and poly-(C.sub.2 -C.sub.10 -.alpha.-olefines) which have been functionalized in relation to isocyanate groups, preferably polypropylene, di- or higher poly-isocyanates or isocyanate prepolymers and optionally relatively high molecular weight polyols and/or low molecular weight chain lengthening agents.

Abstract: The present invention is directed to polyethers obtained by the reaction of a substituted 1,2-epoxy-alkane bearing at least one alkyl substituent containing at least 8 carbon atoms with at least one polyol corresponding to the formulaR(OH).sub.x (1)whereinR is an organic radical andx is an integer having a value of 2 or more,2 or more moles of epoxyalkane being added onto the polyol (1).The present invention is also directed to a process for the preparation of high molecular weight polymers wherein the process is conducted in the presence of the previously described polyethers as a mold release agent.

Abstract: N,N-Diaryl-ureas of the formulaR.sup.1 --NR.sup.2 --CO--NH--R.sup.3whereinR.sup.1 and R.sup.2 denote aryl andR.sup.3 denotes alkyl, aralkyl or aryl, can be prepared by a process in which a diarylamine of the formulaR.sup.1 --NH--R.sup.2is reacted with an isocyanate of the formulaR.sup.3 --NCOwherein R.sup.1, R.sup.2 and R.sup.34 have the above meaning, in the presence of acid compounds and in the presence or absence of an inert solvent and/or diluent at elevated temperature.

Abstract: A liquefied gas pump wherein a vessel contains a supply of liquefied gas which is pumped from its inlet to its outlet by a multi-stage upright centrifugal pump whose first stage is immersed in the supply of liquefied gas in the vessel. The shaft seal at the upper end of the pump housing is held out of contact with liquefied gas by a first flow restrictor above the last stage of the pump, an expansion chamber which is filled with liquefied gas and is located above the first flow restrictor, a gas collecting chamber between the expansion chamber and the seal, and a second flow restrictor which is disposed between the two chambers and prevents penetration of liquefied gas from the expansion chamber into the collecting chamber. The latter is connected with the vessel and/or with a gas collecting tank. The expansion chamber is connected with the second and/or third stage of the pump in order to ensure that it is filled with liquefied gas.

Abstract: A thermal barrier which is interposed between the casing of a pump and the housing of a motor has a first section which resembles a spool and includes a first flange sealingly connected to the casing, a second flange sealingly connected to the housing and a hollow cylindrical core spacedly surrounding the pump shaft between the two flanges. The first section serves primarily or exclusively to establish a seal between the pump casing and the motor housing, and the thermal barrier has a second section which takes up stresses and further serves as a heat insulating and/or heat dissipating device. The second section is removably installed in the space between the two flanges of the first section and spacedly surrounds the core. The second section may be constituted by hollow cylindrical walls, one or more stacks of washers or rings, one or more annuli of parallel tubes, bars, rods, ribs or a combination of such elements.

Abstract: A centrifugal pump has a casing with a cylindrical shell surrounding a volute-type inner section which is formed with a hollow radial extension for admission of fluid into a nipple of the shell. The extension forms part of or constitutes a separable sealing device between a passage of the inner section and a passage of the shell. The inner section is suspended in the shell by one or more pipes which are coaxial with the rotor and/or by one or more projections which extend radially from the inner section and abut against the internal surface of the shell or extend into recesses provided therefor in the internal surface of the shell.

Abstract: A method is disclosed for production of 1-alkyl-4(1H)-oxo-cinnolin-3-carboxylic acids. Mesoxalic acid dialkylester-3,4-methylenedioxy-phenylhydrazone is saponified using 1 to 1.5 Mol alkali into the corresponding monoalkylester, which is cyclicized with a Friedel-Crafts catalyst in the presence of a carboxylic acid anhydride into 6,7-methylenedioxy-4(1H)-oxo-cinnolin-3-carboxylic acid alkylester, which is alkylated with a C.sub.1 -C.sub.4 alkyl halogenide in the presence of alkali in a suitable solvent, after which the ester is saponified. Small amounts of byproduct alkylated in the 2-position are removed by brief heating and precipitation from alkaline solution, leaving a pure 1-alkyl product. The product is useful for the treatment of urinary tract infections.

Abstract: The casing of a centrifugal pump has a shell with a cylindrical periphery having one or more recessed facets with flat or spherical surfaces which are welded to end portions of pipes by circumferentially complete machine-made seams each of which is intersected, in its entirety, by at least one imaginary plane that is normal to the axis of the respective pipe. This renders it possible to use automatic welding equipment and to readily inspect the quality of the connection between the shell and a pipe. The surface of the facet can be formed with a circumferentially complete groove to receive a transducer serving to generate signals denoting the intensity of penetrative radiation which has penetrated through the seam from a source of such radiation in the interior of the respective pipe and in register with the respective seam. The shell is suspended on the arms of a foundation and such arms extend into additional facets which are recessed into the periphery of the shell.