Abstract: The present invention provides a vacuum pump (10) which comprises a turbo-molecular pumping mechanism (12) in series with a Siegbahn pumping mechanism (14). A first pump inlet (16) is provided through which gas can pass through both the turbo-molecular pumping mechanism and the Siegbahn pumping mechanism. Additionally, an inter-stage (inlet 18) is provided through which gas can enter the pump at a location between the turbo-molecular pumping mechanism and the Siegbahn pumping mechanism and pass only through the Siegbahn pumping mechanism. There are flow channels (52, 62) in a first plurality of stages (32, 34) of the Siegbahn pumping mechanism which are in fluid communication with the inter-stage inlet (18) and gas entering the pump through the inter-stage inlet is pumped in parallel along said flow channels.

Abstract: Guide arrangement serving to guide a linear movement of a movable part (2) extending opposite a stationary part (1) along the movement axis and along a transverse direction oriented at a right angle to the movement axis, wherein the guide arrangement includes a support area belonging to the stationary part on which the movable part is slidingly supported and a roller guide arrangement (12) with a roller-guiding area belonging to the stationary part.

Abstract: The invention relates to a process for preparing nitroalkanes by reaction of at least one alkane with at least one nitrating agent in the gas phase, wherein the nitration is carried out in a microstructured reaction zone having parallel channels having hydraulic diameters of less than 2.5 mm and a total specific internal surface area of more than 1600 m2/m3 and the alkane and the nitrating agent are conveyed under a pressure of from 1 bar to 20 bar through the reaction zone and reacted at a temperature of from 150° C. to 650° C. and the reaction products are cooled downstream of the reaction zone and discharged and the at least one nitrating agent is introduced over from two to ten introduction points along the reaction zone.

Abstract: Process for the continuous preparation of an amine by reaction of a primary or secondary alcohol, aldehyde and/or ketone with hydrogen and a nitrogen compound selected from the group consisting of ammonia, primary and secondary amines at a temperature in the range from 60 to 300° C. in the presence of a catalyst comprising copper oxide and aluminum oxide, wherein the reaction takes place in the gas phase and the catalytically active composition of the catalyst before reduction with hydrogen comprises from 20 to 75% by weight of aluminum oxide (Al2O3), from 20 to 75% by weight of oxygen-comprising compounds of copper, calculated as CuO, from 0 to 2% by weight of oxygen-comprising compounds of sodium, calculated as Na2O, and less than 5% by weight of oxygen-comprising compounds of nickel, calculated as NiO, and the shaped catalyst body has a pellet shape having a diameter in the range from 1 to 4 mm and a height in the range from 1 to 4 mm.

Abstract: The invention relates to a method for producing a hydraulic binder, comprising contacting a composition comprising cement clinker, before, during or after the grinding procedure, with (a) a defoaming agent and (b) 0.0005% to 2% by weight, based on the total composition, of at least one air-introducing compound, the defoaming agent (a) comprising 0.0001% to 0.5% by weight, based on the total composition, of at least one defoaming agent of the formula R10—(CmH2m—O—)x—(CdH2d—O—)c—H and the ratio of (a) to (b) being between 1:1 to 1:200.

Abstract: The present invention relates to a process for preparing amines by reacting sugar alcohols with hydrogen and an aminating agent selected from the group of ammonia and primary and secondary amines in the presence of a catalyst at a temperature of from 100° C. to 400° C. and a pressure of from 1 to 40 MPa (from 10 to 400 bar). The catalyst preferably comprises one metal or a plurality of metals or one or more oxygen compounds of the metals of groups 8 and/or 9 and/or 10 and/or 11 of the Periodic Table of the Elements. The sugar alcohol is preferably obtained by hydrogenating the corresponding sugars. The invention further relates to the use of the reaction products as an additive in cement or concrete production and in other fields of use.

Abstract: The invention relates to a method for producing a hydraulic binder, comprising contacting a composition comprising cement clinker, before, during or after the grinding procedure, with (a) a defoaming agent and (b) 0.0005% to 2% by weight, based on the total composition, of at least one air-introducing compound, the defoaming agent (a) comprising 0.0001% to 0.5% by weight, based on the total composition, of at least one defoaming agent of the formula R10—(CmH2m—O—)x—(CdH2d—O—)c—H and the ratio of (a) to (b) being between 1:1 to 1:200.

Abstract: A pump insert (50) for supporting a rotor (14) of a pump comprises an annular resilient support (52) for engaging the body (26) of the pump, the support (52) extending about a rolling bearing (10) having an inner race (12) for engaging the rotor (14), an axially preloaded outer race (16) fixed to the support (52), and a plurality of rolling elements (18) located between the races. During assembly, the rolling bearing (10) can be accurately positioned within the support (52) so that there is a very low tolerance stack-up when the insert (50) is fitted to the rotor (14). Consequently, the position of the rotor (14) will hardly change, if at all, when the rolling bearing (10) is replaced during servicing of the pump.

Abstract: The present invention relates to a continuous process for preparing 3-aminomethyl-3,5,5-trimethylcyclohexylamine by reacting a feed stream comprising 3-cyano-3,5,5-trimethylcyclohexylimine with hydrogen and ammonia over hydrogenation catalysts, wherein the basicity of the reaction mixture is increased during the reaction by bringing the reaction mixture into contact with a basic compound which is not ammonia and/or a basic catalyst after part of the 3-cyano-3,5,5-trimethylcyclohexylimine has been reacted.

Abstract: A pump insert (50) for supporting a rotor (14) of a pump comprises an annular resilient support (52) for engaging the body (26) of the pump, the support (52) extending about a rolling bearing (10) having an inner race (12) for engaging the rotor (14), an axially preloaded outer race (16) fixed to the support (52), and a plurality of rolling elements (18) located between the races. During assembly, the rolling bearing (10) can be accurately positioned within the support (52) so that there is a very low tolerance stack-up when the insert (50) is fitted to the rotor (14). Consequently, the position of the rotor (14) will hardly change, if at all, when the rolling bearing (10) is replaced during servicing of the pump.

Abstract: The present invention relates to a process for preparing 1-adamantyltrimethylammonium hydroxide, by A) reacting 1-adamantyldimethylamine with dimethyl sulfate to give 1-adamantyltrimethylammonium sulfate; and B) subjecting the 1-adamantyltrimethylammonium sulfate obtained in A) to anion exchange with an ion exchanger loaded with OH ions.

Abstract: The invention relates to a process for preparing aminoalkanamides by reacting cyanoalkanoic esters with a) ammonia or an amine and b) hydrogen in the presence of a catalyst, the reaction with component b) being started simultaneously or not later than a maximum of 100 minutes after commencement of the reaction of the cyanoalkanoic ester with component a).

Abstract: A vacuum pump comprises a housing, a drive shaft supported by a beating arrangement for rotation relative to the housing about an axis, and a pumping mechanism comprising a stator component mounted on the housing and a disk-shaped rotor component mounted on the drive shaft axially proximate the stator component. The bearing arrangement comprises a bearing supported in both radial and axial directions by a resilient support, comprising inner and outer annular portions connected by a plurality of flexible members, so that there is a fixed relation between the inner race of the bearing and the outer portion of the resilient support to determine the axial clearance between the rotor and stator components of the pumping mechanism.

Abstract: The present invention relates to a process for preparing a cyclic diamine, comprising the reaction of at least one cyclic alkene with a gas mixture (G) comprising dinitrogen the subsequent conversion of monoxide to give at least one cyclic ketone and then converting the at least one cyclic ketone to a cyclic diamine. The invention also relates to the use of a cyclic diamine with primary and secondary amine functions thus obtained to prepare polyamides and polyurethanes.

Abstract: The present invention relates to 5-isopropyl-3-aminomethyl-2-methyl-1-aminocyclohexane (carvonediamine) and to a process for preparation thereof by a) reacting carvone with hydrogen cyanide, b) then reacting the carvonenitrile obtained in stage a) with ammonia in the presence of an imine formation catalyst and c) then reacting the carvonenitrile imine-containing reaction mixture obtained in stage b) with hydrogen and ammonia over hydrogenation catalysts. The present invention further relates to the use of carvonediamine as a hardener for epoxy resins, as an intermediate in the preparation of diisocyanates, as a starter in the preparation of polyetherols and/or as a monomer for polyamide preparation.

Abstract: The present invention relates to a process for preparing N,N-substituted 3-aminopropan-1-ols by a) reacting secondary amine with acrolein at a temperature of (?50) to 100° C. and a pressure of 0.01 to 300 bar, and b) reacting the reaction mixture obtained in stage a) with hydrogen and ammonia in the presence of a hydrogenation catalyst at a pressure of 1 to 400 bar, wherein the molar ratio of secondary amine to acrolein in stage a) is 1:1 or more and the temperature in stage b) is in the range from (?50) to 70° C. In a preferred embodiment, acrolein which has been obtained from glycerol based on renewable raw materials is used.

Abstract: Guide arrangement, specifically for a machine tool, serving to guide a linear movement of a movable part (2) extending opposite a stationary part (1) along the movement axis and along a transverse direction oriented at a right angle to the movement axis, wherein the guide arrangement includes a support area belonging to the stationary part, on which support area the movable part is slidingly supported against a holding force that acts in a normal direction orthogonal to the directions in which the movable part extends, and wherein the guide arrangement further includes a roller guide arrangement (12) with a roller-guiding area belonging to the stationary part, wherein a load originating from the movable part and having a load component oriented in the opposite direction of the holding force and acting on the roller-guiding area causes within the stationary part a loading effect along a load propagation path leading to the support area, and wherein said load propagation path comprises a path section with a for

Abstract: The present invention relates to a process for preparing N,N-substituted 1,3-propanediamine by a) reacting secondary amine with acrolein at a temperature of from (?50) to 100° C. and a pressure of from 0.01 to 300 bar, and b) reacting the reaction mixture obtained in stage a) with hydrogen and ammonia in the presence of a hydrogenation catalyst at a temperature of from 40 to 400° C. and a pressure of from 1 to 400 bar, wherein the molar ratio of secondary amine to acrolein in stage a) is 2:1 or more and the hydrogenation catalyst used in stage b) comprises cobalt. In a preferred embodiment, acrolein which has been obtained from glycerol based on renewable raw materials is used. The invention further relates to the use of N,N-dimethyl-1,3-propanediamine (DMAPA) based on renewable raw materials as a feedstock for lubricant soaps and other detergents, coagulants, polymers and comb polymers. In a further preferred embodiment, stage b) is performed in the presence of water.

Abstract: Processes comprising: providing a dehydrogenatable compound; and subjecting the dehydrogenatable compound to a dehydrogenation reaction at a temperature of from 150 to 400° C., in the presence of oxygen, and at a temperature profile of the dehydrogenation reaction which does not differ substantially from the temperature profile of the dehydrogenation reaction in the absence of oxygen under otherwise identical conditions.

Abstract: The present invention relates to a process for hydrogenating organic nitriles by means of hydrogen in the presence of a catalyst in a reactor, where the shaped body catalyst is arranged in a fixed bed, wherein the shaped body in the shape of spheres or rods has in each case a diameter 3 mm or less, in the shape of tablets a height of 4 mm or less, and in the case of all other geometries in each case has an equivalent diameter L=1/a? of 0.70 mm or less, where a? is the external surface area per unit volume (mms2/mmp3), where: a ? = A p V p , where Ap is the external surface area of the catalyst particle (mms2) and Vp is the volume of the catalyst particle (mmp3). The present invention further relates to a process for preparing downstream products of isophoronediamine (IPDA) or N,N-dimethylaminopropylamine (DMAPA) from amines prepared according to the invention.