摘要:
Isobutyric acid is oxidatively dehydrogenated to methacrylic acid by passing a gaseous mixture of isobutyric acid, oxygen, nitrogen and optionally water vapor at temperatures of 300.degree.-450.degree. C. and pressures of 0.5 to 5 bar over a catalyst comprising molybdenum oxide, which also contains vanadium, phosphorous and a metal selected from the group consisting of alkali metals, alkaline earth metals, zinc, silver, aluminum, titanium, lead, manganese, iron, cobalt, nickel and tin, preferably precipitated on a solid silica support and calcined at 200.degree. to 400.degree. C. At conversion levels of 80 to 100% of the isobutyric acid used, a methacrylic acid selectivity of 60 to 74% is attained.
摘要:
A volume spring element 152 is located inside the piston 10 which is open to the cylinder 20. The spring element 152 is surrounded by hydraulic liquid on all sides except at its surface 1521 at which the element 152 is attached to the piston 10. When the hydraulic pressure increases, the volume spring element is compressed thereby decreasing its volume. When the hydraulic pressure decreases, the volume spring element expands again. When the hydraulic cylinder is closed off by a valve, then the hydraulic liquid in the piston 10 and in the cylinder 20 is disposed in a closed-off space or chamber. Axial pressures on the cylinder cause a pressure increase in the hydraulic medium. This causes the volume of the volume spring element to be decreased and the piston to be moved axially by the amount corresponding to the decrease of the equally large oil volume in the piston. With the reduction of the hydraulic pressure, the volume spring element expands again causing an axial movement of the piston in a direction out of the cylinder 20. The volume spring element effects the shock absorption of a saddle support which can be hydraulically positioned.
摘要:
An office communication system for transmitting data and/or video information through a communication network to a given device and at a given point in time. An automatic selection device is provided having a timer circuit with a calendar function which may be adjusted by the user along with control device. The automatic selecting device makes a connection through the communication network corresponding to the time desired by the user. A data transmission occurs through a communication interface means at a time which is cost favorable to the user.
摘要:
The invention is directed to a remotely-operable positioning and carrier aratus for remote-handling equipment for use in large-area cells containing process components. The apparatus is mounted on a lifting device of an overhead bridge crane. The apparatus achieves good positioning of the particular remote-handling equipment even at locations which are poorly accessible. The apparatus includes a horizontal beam which is fixed at an eccentric position thereon to the bottom sheave unit of the lifting device so that the horizontal beam defines a long lever arm and a short lever arm. A receiving lever is pivotally connected to the end of the longer lever arm. The receiving lever has an equipment receiving device at its free end. A displaceable counterweight is arranged on the short lever arm for altering the position of the center of gravity of the apparatus. This apparatus makes it possible also to operate in spaces beneath components present in a rack. It is further possible for vertical forces to be applied to objects on one side in parallel relationship to the line of action of the lift cable of the lifting device. With the apparatus of the invention, it is possible to operate with a crane in areas inaccessible with the hook of the crane lifting device.
摘要:
A remotely-operable positioning and carrier arrangement for mounting and itioning remote handling apparatus is described for use in large-area cells containing process equipment particularly in radioactively-charged large-area cells of facilities for reprocessing irradiated nuclear fuels. In such large-area cells, the process components are disposed in racks. Maintenance and servicing work is carried out on the process components and the racks using the remote handling apparatus. The positioning and carrier arrangement which is used for this purpose has a vertically movable support. For a more precise positioning, the positioning and carrier arrangement is transportable and can be suspended on the particular rack at which work is to be done. The positioning and carrier arrangement has a table-like main frame which, in turn, has legs which are disposed horizontally when the frame is suspended on the rack. The ends of the legs are supported against the rack. The vertically movable support is a main sled which is displaceable parallel to the outside of the main frame. The main sled carries a transversely movable equipment sled facing toward the rack which is adapted to carry remote-handling apparatus.
摘要:
The invention is directed to a method of performing remotely-manipulated ntenance work on upwardly extending conduits in a radioactively-ladened cell such as a large-area cell of a nuclear facility for reprocessing irradiated nuclear fuel. A conduit segment is sawn out of a vertical conduit and a new conduit segment welded into place. The removal of cutting chips from the lower vertical end portion of the conduit after the conduit segment has been sawn out is achieved by freezing the liquid medium in the conduit to form frost plugs above and below the tube portion to be removed. A third frost plug is formed in the lower portion of the vertical conduit above the frost plug which has already been produced therein. Thereafter, the tube portion to be removed is cut and separated from the conduit. Then an anchor member is lowered into the lower end portion of the conduit onto the third frost plug. The liquid medium in the lower end of the conduit above the third frost plug is frozen with the cutting chips and the anchor member and, with aid of the anchor member, is withdrawn from the lower end portion of the conduit in an upward direction together with the third frost plug.
摘要:
What is disclosed is a process for the continuous production of isobutyric acid or an alkyl ester thereof by the Koch synthesis, which process comprises reacting propylene, carbon monoxide, and water or an alkanol in the presence of hydrogen fluoride in at least one reaction space containing a liquid phase and a gas phase under high pressure, releasing said pressure at least partially, whereby a gas containing organic compounds from said synthesis evolves from said liquid phase, adding oxygen to said evolved gas and at least partially combusting the organic compounds contained therein, then contacting the evolved gas containing the at least partially combusted organic compounds with at least a portion of the water or alkanol to be reacted with said propylene and carbon monoxide, whereby at least a portion of said combusted organic compounds are absorbed by said water or alkanol, returning said water or alkanol containing the absorbed combusted organic compounds to said reaction space, and discharging any unabsorbed gas from the reaction system.
摘要:
A computer, in particular a personal computer with the voice input and a voice output system thereby allowing the computer to be used as an integrated dictation system.The computer includes analog-to-digital conversion means for converting analog signals corresponding to the spoken word into digital signals. These digital signals are stored in the storage device of the computer. The digital representations are recalled from the storage and converted to sounds by a digital-to-analog conversion means and a headset for the user to listen to while transcribing the words via the keyboard of the computer.
摘要:
Apparatus is described for feeding a wire from a wire coil to a processingtation. When wire is taken from a coil and fed to a processing station, because of the tension imposed on the wire, the wire end carries out uncontrolled movements which in arc welding are known as "pig-tailing" effects. In order to obviate such uncontrolled movements of the wire after issuing from conventional guide means, in the present wire guide apparatus the wire is guided with a radius of curvature r which is equal to the radius of curvature which the cylindrical spring formed by the cylindrically wound wire has in its relaxed state. The wire guide apparatus comprises a guide tube which is joined tangentially to the coil housing and which is constructed with a slightly curved shape. Connected to the guide tube is a mouthpiece which has a curved tubular duct the radius of curvature of which is equal to the radius of curvature r. The outer diameter of the cylindrical reel on which the wire is wound is preferably greater than the inner diameter of the relaxed cylindrical spring constituted by the wound wire.
摘要:
The stress test rig consists of a rigidly mounted part which contains the devices uniformly used for all types of test gears and an assembly truck (37) which holds the test gear (16) and the required adapter devices. A test rig gear unit (2) forms a continuous stress circuit with a superimposed gear unit (9), an adaptation gear (23) and a second test rig gear (19) wherein the stress torque is set by a control unit (15) through the superimposed gear unit (9). The regulation variable for the stress torque is determined up to more than 80% by a control network (31). The test rig gear unit (2) is a bevel gear wheel and the superimposed gear unit (9) has a bevel gear step (13) so that the output shaft (14) of the superimposed gear unit (9) is pivoted and has a height adapted to an input shaft of an adaptation gear unit (23) or of a test gear unit (16).