Abstract: A laser device with one or more active regions, such as quantum wells, gain/lighting media, or other devices, and one or more non-absorbing regions, may be formed by a first growth run (growing a first semiconductor layer), then performing selective, shallow-depth etching, and then a second growth run (growing a second semiconductor layer). The laser device may include a first portion, one or more active regions located on the first portion, and a second portion located on the active region(s). A third portion may be located on one or more ends of the first portion and on the second portion. The third portion may be formed during the second growth run, after the etching step. The non-absorbing region(s) may be formed by the third portion and the end(s) of the first portion. If desired, the non-absorbing region(s) may be produced without annealing or locally-induced quantum well intermixing.

Abstract: The presently claimed invention relates to the use of at least one compound of general formula (I) as an emulsifier or a stabilizer. The presently claimed invention further relates to the use of at least one compound of general formula (I) as an emulsifier or stabilizer in a polymerization reaction, preferably an emulsion polymerization. The presently claimed invention also relates to a method of emulsifying and/or stabilizing or dispersing liquids or solids in emulsion polymerization using at least one compound of general formula (I). Further, the presently claimed invention relates to a cleaning composition comprising at least one compound of general formula (I) and at least one additive.

Abstract: A laser device with one or more active regions, such as quantum wells, gain/lighting media, or other devices, and one or more non-absorbing regions, may be formed by a first growth run (growing a first semiconductor layer), then performing selective, shallow-depth etching, and then a second growth run (growing a second semiconductor layer). The laser device may include a first portion, one or more active regions located on the first portion, and a second portion located on the active region(s). A third portion may be located on one or more ends of the first portion and on the second portion. The third portion may be formed during the second growth run, after the etching step. The non-absorbing region(s) may be formed by the third portion and the end(s) of the first portion. If desired, the non-absorbing region(s) may be produced without annealing or locally-induced quantum well intermixing.

Abstract: Structural element for a motor vehicle, in particular a frame part for a chassis or a passenger compartment of the motor vehicle, having at least a first and a second fiber layer forming a rigid fiber composite, the fiber layers being laminated to one another at least in sections, and at least one electrical flat conductor arranged between the fiber layers and laminated to the fiber layers. The flat conductor has a relief structure on at least one surface facing at least one fiber layer.

Abstract: Structural element for a motor vehicle, in particular a frame part for a chassis or a passenger compartment of the motor vehicle, having at least a first and a second fiber layer forming a rigid fiber composite, the fiber layers being laminated to one another at least in sections, and at least one electrical flat conductor arranged between the fiber layers and laminated to the fiber layers. The flat conductor has a relief structure on at least one surface facing at least one fiber layer.

Abstract: Water-soluble, hydrophobically associating copolymers which comprise new types of hydrophobically associating monomers. The monomers comprise an ethylenically unsaturated group and a polyether group with block structure comprising a hydrophilic polyalkylene oxide block which consists essentially of ethylene oxide groups, and a terminal, hydrophobic polyalkylene oxide block which consists of alkylene oxides with at least 4, preferably at least 5 carbon atoms.

Abstract: The invention relates to improved novel carrier fluids for abrasives, in particular cutting fluids, for wafer production, the use thereof and a method of cutting wafers.

Abstract: The invention relates to a method of controlling a hydrogenation of a starting material in a hydrogenation reactor, in which the amount of hydrogen reacted in the hydrogenation is firstly determined, the ratio of the amount of hydrogen reacted to the amount of starting material fed in is then derived, this ratio is compared with a prescribed value and, finally, at least one process parameter is altered if the ratio of the amount of hydrogen reacted to the amount of starting material fed in deviates by a prescribed amount from the prescribed value.

Abstract: Water-soluble, hydrophobically associating copolymers which comprise new types of hydrophobically associating monomers. The monomers comprise an ethylenically unsaturated group and a polyether group with block structure comprising a hydrophilic polyalkylene oxide block which consists essentially of ethylene oxide groups, and a terminal, hydrophobic polyalkylene oxide block which consists of alkylene oxides with at least 4, preferably at least 5 carbon atoms.

Abstract: The invention relates to a catalyst provided in the form of an extrudate, which contains 5 to 85% by weight of copper oxide and comprises, in the active material and as binders, the same oxidic carrier material. The invention also relates to the use of the catalyst for hydrogenating carbonyl compounds.

Abstract: The present invention relates to a process for preparing 3-alkoxypropan-1-ols of the general formula I by catalytic hydrogenation of esters of the general formula II, where the radicals R1 and R2 and R3, R4 and R5 are each, independently of one another, a straight-chain or branched C1-C20-alkyl radical which may optionally be substituted by one or more C1-C20-alkoxy radicals or interrupted by one or more oxygen atoms in the chain, C6-C20-aryl, C7-C20-arylalkyl which may optionally be substituted by one or more C1-C20-alkoxy radicals or interrupted by one or more oxygen atoms in the alkyl chain, C7-C20-alkylaryl which may optionally be substituted by one or more C1-C20-alkoxy radicals or interrupted by one or more oxygen atoms in the alkyl chain, a C1-C20-cycloalkyl radical which may optionally be substituted by one or more C1-C20-alkoxy radicals and R2, R3 and R4 can, independently of one another, also be hydrogen, over chromium- and nickel-free catalysts.

Abstract: The present invention provides a process for distillatively purifying tetrahydrofuran in the presence of a polar solvent.

Abstract: The present invention relates to a process for preparing optically active hydroxy-, alkoxy-, amino-, alkyl-, aryl- or chlorine-substituted alcohols or hydroxy carboxylic acids having from 3 to 25 carbon atoms or their acid derivatives or cyclization products by hydrogenating the correspondingly substituted optically active mono- or dicarboxylic acids or their acid derivatives in the presence of a catalyst whose active component consists of rhenium or of rhenium and comprises at least one further element having an atomic number of from 22 to 83, with the provisos that a. the at least one further element having an atomic number of from 22 to 83 is not ruthenium and b.

Abstract: Catalyst in the form of an extrudate which comprises from 5 to 85% by weight of copper oxide and in which the same oxidic support material is present in the active composition and as binder, and the use of the catalyst for the hydrogenation of carbonyl compounds.

Abstract: A process for variably preparing mixtures of optionally alkyl-substituted BDO, GBL and THF by two-stage hydrogenation in the gas phase of C4 dicarboxylic acids and/or derivatives thereof, which comprises a) hydrogenating in a gas phase a gas stream of C4 dicarboxylic acids and/or derivatives thereof over a particular catalyst at a particular pressure and temperature to give a stream mainly containing of optionally alkyl-substituted GBL and THF, b) removing any succinct anhydride, c) converting the products remaining predominantly in the gas phase in the partial condensation, THF, water and GBL to give a stream comprising a mixture of BDO, GBL and THF, d) removing the hydrogen from the products and recycling it into the hydrogenation, e) distillatively separating the products, THF, BDO, GBL and water, if appropriate recycling a GBL-rich stream or if appropriate discharging it, and working up BDO, THF and GBL distillatively, and setting the ratio of the products, THF, GBL and BDO, relative to one another wi

Abstract: A catalyst for the hydrogenation of C4-dicarboxylic acids and/or derivatives thereof, preferably maleic anhydride, in the gas phase comprises a) 20-94% by weight of copper oxide (CuO), preferably 40-92% by weight of CuO, in particular 60-90% by weight of CuO, and b) 0.005-5% by weight, preferably 0.01-3% by weight, in particular 0.05-2% by weight, palladium and/or a palladium compound (calculated as metallic palladium) and c) 2-79.995% by weight, preferably 5-59.99% by weight, in particular 8-39.95% by weight, of an oxidic support selected from the group consisting of the oxides of Al, Si, Zn, La, Ce, the elements of groups IIIA to VIIIA and of groups IA and IIA of the Periodic Table of the Elements.

Abstract: Crude water-containing tetrahydrofuran is purified by passing the crude tetrahydrofuran through three distillation columns, withdrawing water from the bottom of the first column, recycling water-containing tetrahydrofuran from the top of the second column into the first column, passing a sidestream of the first column into the second column, recycling the bottom product of the third column into the first column, and withdrawing a distillate at the top of the first column. Additionally, a sidestream of the second column is passed into the third column and the purified tetrahydrofuran is recovered as the top product of the third column.

Abstract: A catalyst for the hydrogenation of C4-dicarboxylic acids and/or derivatives thereof, preferably maleic anhydride, in the gas phase comprises a) 20-94% by weight of copper oxide (CuO), preferably 40-92% by weight of CuO, in particular 60-90% by weight of CuO, and b) 0.005-5% by weight, preferably 0.01-3% by weight, in particular 0.05-2% by weight, palladium and/or a palladium compound (calculated as metallic palladium) and c) 2-79.995% by weight, preferably 5-59.99% by weight, in particular 8-39.95% by weight, of an oxidic support selected from the group consisting of the oxides of Al, Si, Zn, La, Ce, the elements of groups IIIA to VIIIA and of groups IA and IIA of the Periodic Table of the Elements.

Abstract: Optionally alkyl-substituted 1,4-butanediol is prepared from C4-dicarboxylic acids and/or of derivatives thereof by: a) a gas stream of the C4-dicarboxylic acid or the derivative thereof in a first reactor in the gas phase to obtain a product which contains mainly optionally alkyl-substituted ?-butyro-lactone; b) removing succinic anhydride from the product of step a); c) catalytically hydrogenating the product of step b) in a second reactor in the gas phase to obtain optionally alkyl-substituted 1,4-butanediol; d) removing the desired product from intermediates, by-products and any unconverted reactants; and e) optionally recycling unconverted intermediates into one or both hydrogenation stages. The catalysts employed in each of the hydrogenation stages comprise ?95% by weight of CuO, and ?5% by weight of an oxidic support, and the second reactor has a higher pressure than the first reactor.

Abstract: A process for preparing toluene derivatives of the formula I, where R1, R2 and R3 independently of one another are hydrogen, halogen, C1–C6-alkyl, hydroxyl or C1–C6-alkoxy, by hydrogenating benzaldehydes and/or benzyl alcohols of the formula II, with hydrogen in the presence of a catalyst, which is described in more detail in the description.