摘要:
A supported catalyst includes: a) 0.5-15 wt. % of one or more Cu-II compounds, the quantitative amounts referring to copper metal; b) 0.1-8 wt. % of one or more alkali metal compounds, the quantitative amounts referring to alkali metal; c) 0.1-10 wt. % of an oxide mixture including; c1) 80-95 mole % of oxides of cerite rare earths with atomic Nos. 57 to 62, except promethium, and c2) 5-20 mole % of zirconium dioxide, where c1) and c2) must together total 100 mole % and the quantitative amount of c) refers to the oxides of the mixture, and d) the remainder up to 100 wt. % being .gamma. and/or .alpha.-aluminum oxide as support material, wherein e) the support material d) has a total pore volume in the range from 0.65 to 1.2 cm.sup.3 /g, and wherein f) the supported catalyst is present in the form of cylindrical hollow bodies having at least one passage channel, the ratio of height h to external diameter d.sup.e being less than 1.5 for diameters d.sub.e of up to 6 mm, and the ratio h/d.sub.e being less than 0.6 for diameter d.sub.e greater than 6 mm. A process for producing the supported catalyst is also described.
摘要:
A process for preparing a shell-type catalyst which comprises applying to a substantially nonporous inorganic support material having a BET surface area of
摘要:
A sliding bearing for axial and/or radial arrangement of a first bearing member in relation to a second bearing member, comprises a second bearing member, which has a bearing recess provided with a second slide face; a first bearing member, which is lodged in the bearing recess and which is mounted axially and/or radially, the first bearing member having a first slide face, which is opposite the second slide face and spaced therefrom by a clearance; at least one sliding/guiding element, which is disposed between the first and the second bearing members and fixed in relation to one bearing member, for guidance of a motion of the first relative to the second bearing member; an equalizing compound, which is disposed between the at least one sliding/guiding element and the bearing member relative to which is fixed the at least one sliding/guiding element, for adaptation of the guide clearance between the at least one sliding/guiding element and the slide face that is displaceable in relation thereto, the equalizing compound being solid in the operating state of the sliding bearing and free-flowing prior thereto.
摘要:
A process for the continuous and discontinuous production of tetrahydrofuran polymers by homopolymerizing tetrahydrofuran or copolymerizing tetrahydrofuran with 1,2-alkylene oxides in the presence of compounds with reactive hydrogen or carboxylic acid anhydrides on an acid-treated, calcined and granulated aluminium silicate catalyst which may consist of amorphous aluminium silicate, a zeolite or kaolin. By keeping the concentration of carboxylic acid anhydride or alkylene oxide constant below 1 wt. % in the polymerization recipe throughout the polymerization it is possible to largely prevent the formation of cyclic ethers and to obtain a polymer with a very narrow molecular weight distribution. In granular form, the catalysts exhibit a hitherto unknown activity and form polymers with a very narrow molecular weight distribution and low color and acid numbers.
摘要:
A circuit arrangement for the implementation of a fast discrete Fourier transform in real time through the controlled operation of cross-linked butterfly, or kernel, operators. The circuit arrangement will successively transmit the two halves of a sequence of complex input words through a series-parallel input register and an interim data storage to a plurality of butterfly operators which operate in parallel, whose outputs are switchable by a multiplexer for recursive linkage with the interim storage or, in essence, for the delivery of the frequency range-output words to a parallel-series output register.
摘要:
A self developing type photographic apparatus wherein one of the spread rollers is driven by one or two toothed racks forming part of or constituting a manually reciprocable handle. One of the racks further rotates a gear which programs the movements of an expelling device for exposed film units, the movements of a device which controls the width of the gap between the spread rollers and the cocking of the shutter.
摘要:
The invention relates to an active impact protection system (1) for a knee area and/or a lower leg area of a vehicle occupant in a motor vehicle, particularly in a passenger car. The impact protection system (1) comprises an impact element (2) that can be extended toward the vehicle occupant out of a passive position and into an active position by means of a drive device (4). A particularly advantageous design results when the impact element (2) is formed by a lid of a passenger-side glove compartment (3).
摘要:
A method of separating heteropoly compounds from mixtures of polyethers, polyesters and/or polyether esters, a protic component and heteropoly compounds, wherein the protic component is removed from the mixture and subsequently separating off the heteropoly compound as a separate phase. The polymer phase which remains is preferably brought into further contact with a solid adsorbent that is capable of adsorbing heteropoly compounds.
摘要:
A star-shaped array of channeled rolls in a rolling mill for rolling bar stock has the rolls pressed together with a pressing force exceeding the rolling force by a prestressing force sufficient to cause frustoconical flanks of the rolls to forceably press against one another. This stabilizes the rolls and also permits a fine adjustment of the diameter of the passage defined between them.
摘要:
The shutter mechanism includes an aperture-unblocking member mounted for movement between an unactivated aperture-blocking position and an activated aperture-unblocking position. A cocked drive mechanism is coupled to the aperture-unblocking member and is operative when released for moving the member from the unactivated to the activated position. An inertial braking mechanism is driven by the drive mechanism when the latter moves the aperture-unblocking member to the activated position, and is operative during such movement for applying to the drive mechanism an inertial braking force slowing the movement of the aperture-unblocking member to the activated position. The drive mechanism includes a drive cam, and the inertial braking mechanism includes a driven cam. The surface of the drive cam bears upon the surface of the driven cam and transmits to the driven cam the drive force by means of which the drive mechanism drives the inertial braking mechanism. The cams are so configured that, as the drive mechanism drives the inertial braking mechanism, the surface of the drive cam rolls along the surface of the driven cam.