Abstract:
The invention relates to a semiconductor component which is capable of blocking such as an (IGBT), a thyristor, a GTO or diodes, especially schottky diodes. An insulator profile section (10a, 10b, 10c, 10d, 11) provided in the border area of an anode metallic coating (1, 31) is fixed (directly in the edge area) on the substrate (9) of the component. The insulator profile has a curved area (KB) and a base area (SB), said curved area having a surface (OF) which begins flat and curves outward and upward in a steadily increasing manner. A metallic coating (MET1; 30a, 30b, 30c, 30d, 31b) is deposited on the surface (OF). Said coating directly follows the surface curvature and laterally extends the inner anode metallic coating. The upper end of the curved metallic coating (MET1; 30a, 30b . . . ) is distanced and insulated from one of these surrounding outer metallic coatings (MET2; 3) by the surrounding base area (SB) of the insulator profile (10a, . . . , 11) such that an extensively constant course of the line of force which evades extreme values results between both metallic coatings (1, 31, MET1; 3, MET2) when reverse voltage or blocking voltage is applied between the interspaced metallic coatings.
Abstract:
Process for the continuous preparation of unsaturated ketones of the formula I where the dashed line can be an additional C—C bond, R1 is an alkyl, and R2 is an aliphatic hydrocarbon having from 1 to 37 carbons, a cycloalkyl or a cycloalkylalkyl, by reacting an unsaturated alcohol of the formula II with an alkyl acetoacetate of the formula III where R3 is an alkyl having from 1 to 5 carbons, in the presence or organic aluminum compounds as catalyst.
Abstract:
The invention relates to a semiconductor component which is capable of blocking such as an (IGBT), a thyristor, a GTO or diodes, especially schottky diodes. An insulator profile section (10a, 10b, 10c, 10d, 11) provided in the border area of an anode metallic coating (1, 31) is fixed (directly in the edge area) on the substrate (9) of the component. The insulator profile has a curved area (KB) and a base area (SB), said curved area having a surface (OF) which begins flat and curves outward and upward in a steadily increasing manner. A metallic coating MET1; 30a, 30b, 30c, 30d, 31b) is deposited on the surface (OF). Said coating directly follows the surface curvature and laterally extends the inner anode metallic coating. The upper end of the curved metallic coating (MET1; 30a, 30b . . . ) is distanced and insulated from one of these surrounding outer metallic coatings (MET2; 3) by the surrounding base area (SB) of the insulator profile (10a, . . . , 11) such that an extensively constant course of the line of force which evades extreme values results between both metallic coatings (1, 31, MET1; 3, MET2) when reverse voltage or blocking voltage is applied between the interspaced metallic coatings.
Abstract:
Higher &agr;,&bgr;-unsaturated alcohols are prepared by monoethynylation of a ketone by the NH3/KOH method, if desired hydrogenation of the acetylene alcohol in the presence of hydrogen over a Pd-containing thin layer catalyst, purifying distillation of the hydrogenation product, preferably in a dividing wall column with recirculation of the unreacted ketone to the ethynylation step, and, if desired, preparation of higher alcohols having in each case 5 more carbon atoms in the chain by reacting the alcohols prepared by monoethynylation and, if desired, partial hydrogenation with alkyl acetoacetates diketene in a Carroll reaction to form ketones and using these as starting materials for the steps ethynylation, optional hydrogenation and fractional distillation.
Abstract:
A cover, constructed as a solar generator, for closing an opening in the bodywork of a vehicle which consists of a transparent panel, an assembly attached to the underside of the panel, which assembly consists of a solar cell field and a plastics material in which the latter is embedded, a frame foamed onto the peripheral edge area of the panel, optionally reinforced by embedded profiled bars, and a foam-molded backing layer connected in one piece with the frame. The simply constructed solar cover producible in this way without seal and foam-restricting arrangements exerting contact pressure forces on the assembly allows the application of elevated foaming pressures without the risk of damage to the sensitive solar cells. The backing layer protects the assembly from below and allows the foaming on of projections, ribs and the like. A preferred method of producing the solar cover is also proposed, in which the foaming pressure is >1 bar.
Abstract:
A roof panel incorporating a solar power generator, for a motor vehicle sunshine roof, has a foamed plastic frame around the edge of the panel and a plurality of crystalline solar cells forming a field of solar cells extending considerably into the region of the frame. Special precautions ensure that the crystalline solar cells, which are susceptible to breakage, are not damaged when foaming around the cover to form the frame. The solar cell field enables good use of solar energy and can be accommodated in a lightweight panel.
Abstract:
Alkenes are prepared by partial hydrogenation of alkynes in the liquid phase at from 20 to 250° C. and hydrogen partial pressures of from 0.3 to 200 bar over fixed-bed supported palladium catalysts which are obtainable by heating the support material in the air, cooling, applying a palladium compound and, if required, additionally other metal ions for doping purposes, molding and processing to give monolithic catalyst elements, by a process in which A) alkynes of 10 to 30 carbon atoms are used as starting compounds, B) the palladium compound and, if required, the other metal ions are applied to the support material by impregnation of the heated and cooled support material with a solution containing palladium salts and, if required, other metal ions and subsequent drying, and C) from 10 to 2000 ppm of carbon monoxide (CO) are added to the hydrogenation gas or a corresponding amount of CO is allowed to form in the liquid phase by slight decomposition of a compound which is added to the reaction mixture and eliminates CO under the reaction conditions. The process is particularly advantageous if the partial hydrogenation is carried out in a tube reactor by the trickle-bed or liquid phase procedure with product recycling at cross-sectional loadings of from 20 to 500 m3/m2*h. The process is particularly suitable for the preparation of 3,7,11,15-tetramethyl-1-hexadecen-3-ol (isophytol), 3,7,11-trimethyl-l-dodecen-3-ol (tetrahydronerolidol), 3,7,11-trimethyl-1,4-dodecadien-3-ol, 3,7,11-trimethyl-1,6-dodecadien-3-ol (dihydronerolidol), 3,7-dimethyloct-1,6-dien-3-ol or 3,7-dimethyloct-1-en-3-ol from the corresponding alkynes.
Abstract:
A process for preparing .gamma.,.delta.-unsaturated ketones of the general formula I ##STR1## by reacting an allyl alcohol of the general formula II ##STR2## in which R.sup.1 is H or a hydrocarbon radical having 1 to 20 carbon atoms, with diketene or an alkyl acetoacetate of the general formula III ##STR3## in which R.sup.2 is alkyl having 1 to 4 carbon atoms in an unmodified or modified Carroll reaction in the presence of an aluminum catalyst, wherein aluminum compounds which are stable liquids at room temperature, or a mixture of such aluminum compounds, which comprise at least one radical formed from an alkyl acetoacetate and 1 or 2 alkoxy radicals, or else comprise exclusively radicals formed from alkyl acetoacetates, which are esterified with sec-butanol or isobutanol, or else are esterified with at least two different alcohols, are used as aluminum catalyst. Also claimed are the novel mixtures of aluminum compounds which comprise radicals which are formed exclusively from alkyl acetoacetates and are esterified with at least two different alkanols, and the batchwise and continuous preparation of the liquid aluminum catalysts.