Abstract: The invention relates to a system and method of detecting impurities in a cylindrically shaped transparent medium, wherein the cylindrically shaped transparent medium is illuminated with electromagnetic radiation, and the radiation having components emerging radially from the medium, and at least some of the components are received by a detector for detecting impurities of the medium. The components are detected at a multiplicity of relative angular positions around the symmetry axis of the cylinder, so as to form an impurity diagram that may be analyzed to detect and measure impurities in the medium.

Abstract: A method of fluxless bonding first and second members to each other by temperature controlled laser soldering is provided. The first and second members carrying solder pads are arranged in a mounting device. Mechanical vibration is directly applied to the mounting device carrying the members during heating by laser irradiation and the mechanical vibration is then switched off before the cooling-off phase of the soldered joints.

Abstract: The invention relates to an interferometric method for measuring a height of a first region on a first surface, the first surface having first areas having first optical properties and second areas having second optical properties, the method comprising the steps of generating of first and second coherent light beams, reflecting at least the first coherent light beam from the first region into a first return beam and reflecting the second coherent light beam from a second region into a second return beam, measuring at least a first reflectivity of the first region, determining a topography-dependent phase shift of the first and second return beams for the height measurement based on the first reflectivity.

Abstract: An optical device has a rotatable birefringent crystal. The crystal is rotatable around a first axis (4; 42) and has a crystallographic-optical axis (6; 44) in a plane that is perpendicular to the first axis. In addition, the crystal is rotated around the first axis in order to control a displacement (&Dgr;x) of a light beam in the plane when the light beam is polarized within the plane and directed onto the crystal.

Abstract: A new process for the preparation of specific aromatic aldehydes by ozonolysis of aromatic alkenes is provided. This new process can be advantageously integrated into a synthesis of specific chiral diols using aromatic aldehydes of this type.

Abstract: This invention relates to covulcanizable anti-aging agents which can be produced by the reaction of p-phenylenediamines, which are optionally substituted, and/or of sterically hindered phenols, with bifunctional alkyl, aryl and/or aralkyl compounds and by subsequent reaction of the products thus obtained with sulfur and/or sulfur donor compounds. The anti-aging agents according to the present invention maintain their efficacy over a long period of time and are distinguished in particular by the fact that in practice, they are hardly extracted from the vulcanized products by water, by oil and/or petrol, or by hydraulic fluids.

Abstract: The invention provides a process for preparing 4-aminodiphenylamine, an important starting product for synthesizing antioxidants and stabilizers in the rubber and polymer industry, by hydrogenating nitrosobenzene with hydrogen in the presence of a proton acid as catalyst and in the presence of a hydrogenating catalyst, optionally in the presence of an inert organic solvent and thermally decomposing the 4-ADPA ammonium salt produced in this way, wherein 4-ADPA is obtained. 4-aminodiphenylamine is produced in good yields and high purity by the process according to the present invention. Furthermore, no effluent is produced, which makes the process particularly economic and ecological.

Abstract: The invention provides a process for preparing 4-aminodiphenylamine, an important starting product for synthesizing antioxidants and stabilizers in the rubber and polymer industry, by hydrogenating nitrosobenzene with hydrogen in the presence of a proton acid as catalyst and in the presence of a hydrogenating catalyst, optionally in the presence of an inert organic solvent and thermally decomposing the 4-ADPA ammonium salt produced in this way, wherein 4-ADPA is obtained.

Abstract: This invention relates to covulcanizable anti-aging agents which can be produced by the reaction of p-phenylenediamines, which are optionally substituted, and/or of sterically hindered phenols, with bifunctional alkyl, aryl and/or aralkyl compounds and by subsequent reaction of the products thus obtained with sulfur and/or sulfur donor compounds. The anti-aging agents according to the present invention maintain their efficacy over a long period of time and are distinguished in particular by the fact that in practice, they are hardly extracted from the vulcanized products by water, by oil and/or petrol, or by hydraulic fluids.

Abstract: The present invention provides a process for preparing (4-nitroso-phenyl)phenyl-hydroxylamine which is characterized in that nitrobenzene is reacted in the presence of hydroxide and/or oxide-containing bases, optionally in the presence of solvents, at temperatures of 20 to 180.degree. C. and pressures of 0.1 to 10 bar.The process according to the invention has the particular advantage that it uses inexpensive and cost-effective nitrobenzene as starting material instead of the nitrosobenzene conventionally used hitherto.

Abstract: 4-aminodiphenylamines are prepared by hydrogenating nitrosobenzene or mixtures of nitrosobenzene and nitrobenzene with hydrogen in the presence of bases containing hydroxide, oxide and/or alkoxide groups and heterogeneous catalysts in inert aprotic solvents at temperatures of from 0 to 200.degree. C. and at pressures of from 0.1 to 150 bar.

Abstract: This invention relates to easily conveyable and easily meterable mixtures having high stability in storage, containing aromatic mineral oils and phenylenediamines, the content of phenylenediamines in the mixture being 1 to 99 wt. %. The mixtures of mineral oils and phenylenediamines according to the invention are used in the production of rubbers and rubber articles.

Abstract: 4-aminodiphenylamines are produced by hydrogenating nitrobenzene with hydrogen in the presence of bases containing hydroxide and/or oxide groups and heterogeneous catalysts and in the presence of inert aprotic solvents at temperatures of 0 to 200.degree. C. and pressures of 0.1 to 150 bars.

Abstract: The invention relates to enantiomerically pure bisphosphines of the general formula (I) ##STR1## where R is as defined in the description,a process for their preparation and their use in metal complexes as catalysts for asymmetric reactions, in particular asymmetric hydrogenations.

Abstract: The invention relates to novel bisphosphonates and to processes for their preparation and for their resolution into the enantiomers. The bisphosphonates according to the invention are valuable intermediates for the preparation of bisphosphine compounds, especially chiral bisphosphine ligands. These in turn are constituents of transition metal complexes which are used as catalysts inter alia in asymmetric hydrogenation.The novel bisphosphonates have the general formula (I) ##STR1## in which R.sup.1 is linear or branched alkyl having up to 6 carbon atoms, aryl or aralkyl, each of which can optionally be substituted, or two radicals R.sup.1 together are a bridging hydrocarbon radical having up to 6 carbon atoms,and can exist in the form of their racemates or as enantiomers.

Abstract: The invention relates to enantiomerically pure bisphosphines of the general formula (I) ##STR1## where R is as defined in the description,a process for their preparation and their use in metal complexes as catalysts for asymmetric reactions, in particular asymmetric hydrogenations.

Abstract: The invention relates to novel enantiomerically pure bisphosphines of the general formula (I) ##STR1## in which R, R.sup.1 and R.sup.2 have the meanings given in the description, a process for the preparation thereof and the use thereof in metal complexes as catalysts for asymmetric hydrogenations.

Abstract: The present invention relates to novel 2-arylpropenoic acids, derivatives thereof, processes for their preparation and their use in the preparation of S-ketoprofen.

Abstract: New .alpha.-trifluoromethyl-substituted, saturated bicyclic amines of the formula ##STR1## in which R.sup.1 represents hydrogen, C.sub.1 - to C.sub.8 -alkyl or C.sub.1 - to C.sub.8 -alkoxy,R.sup.2 represents hydrogen or C.sub.1 - to C.sub.4 -alkyl,n represents zero or 1,A represents ##STR2## B represents NH or ##STR3## and C represents ##STR4## in which A, B and C are either each different from one another or C represents ##STR5## and one of A and B represents NH and the other represents ##STR6## and R.sup.3 denotes hydrogen or C.sub.1 - to C.sub.4 -alkyl and the ring D is saturated.