Abstract: A process for producing, on a metallic substrate, a geometric metal structure having a precise contour, including the steps of: solder coating a solder paste onto the substrate by screen printing to create the geometric metal structure, the solder paste comprising an organic binder system, and 80 to 95 weight % of a mixture of a nickel-based solder and a pulverulent alloy of nickel with at least one member selected from the group consisting of chromium, molybdenum, tungsten, manganese and iron, provided as a higher-melting metallic filler, wherein a weight ratio of solder to filler is 2-6:1, an average grain size of the solder is between 10 and 50 &mgr;m, and a grain size ratio of solder to filler, relative to the average grain size is from 0.5-2.5:1; drying the structure; decomposing the organic binder system present in the solder paste, without leaving a reside, by a heat treatment; and raising the temperature until the resulting solder material liquifies.

Abstract: A toner or a mixture of toners, comprises a pyrogenically synthesized alumina-silica mixed oxide as a component in combination with other components necessary to complete a toner formulation. The surface of the mixed alumina-silica oxide material.

Abstract: A process for the preparation of mixtures of organosilicon disulfanes with a high disulfane content includes first reacting finely divided sodium and sulfur in an organic solvent, and then reacting the resulting Na2Sx, product further with a halogenoalkylalkoxysilane to give the desired product.

Abstract: A ferroceneylphosphine ligand and complexes prepared therefrom for homogeneous catalytic enantioselective hydrogenation, the ligand having the formula (I): Another aspect of the invention is directed to a ferroceneylphosphine ligand of formula (II),

Abstract: A process for preparing alkali metal alkoxides of alcohols comprising reacting an alkali metal amalgam with an alcohol having at least 3 carbon atoms in the presence of a powder catalyst comprising a transition metal carbide, nitride or carbonitride, to form a reaction mixture, wherein the reaction mixture is subjected to ultrasound during reaction.

Abstract: A partially hydrophobic precipitated silica having a methanol wettability of 10 to 49%, in particular with a DBP uptake on a dry basis of greater than 250 g/100 g and a mean particle size of 1 to 12 &mgr;m and/or a carbon content of 0.3 to 1.85% and/or a loss on drying of 2.6 to 10.0% and/or a pH value of 5.5 to 10.0, is prepared by mixing the amount of water-repellent agent with the precipitated silica suspension at very short residence time and low pH value, filtering off the solid substance, washing free of salt, drying, post-treating thermally and milling. The partially hydrophobic precipitated silica can be used in active substance formulations and active substance formulations of hydrolysis-sensitive substance and in defoaming agents.

Abstract: A method for the production of D-pantothenic acid by the fermentation of microorganisms of the family Enterobacteriacae producing D-pantothenic acid which is characterized in that strains are used which a) Contain the plasmid pFV31 and/or pFV202 and that b) A panD gene and optionally other nucleotide sequences coding for aspartate-1-decarboxylase are enhanced, especially overexpressed in these microorganisms, c) The pantothenic acid is enriched in the medium or in the cells of the microorganisms and d) The pantothenic acid formed is isolated.

Abstract: The invention involves a procedure for the catalytic enantioselective reduction of ketones to chiral alcohols. Heretofore, this reaction was carried out batch-wise. Because, in this procedure, one utilizes a catalyst increased in size with polymer, it is possible to carry out the reaction in a quasi-continuous manner in a membrane reactor. In contrast to the state of the art, one thus dramatically increases the operative life of the catalyst.

Abstract: The present invention relates to a process for neutralizing and reducing the residual halogen content in alkoxysilanes and alkoxysilane-based compositions, which includes treating an alkoxysilane having a residual content of acidic halide, or a corresponding alkoxysilane-based composition, with metallic magnesium in the presence of an alcohol and separating off the resulting solids.

Abstract: Process for the preparation of N-acetyl protected amino acids of Formula I by amido carbonylation utilizing carbon monoxide, nitrile, and an aldehyde in the presence of a metal catalyst.

Abstract: A process for preparing an alkoxysilane with an acidic chloride content of less than 10 ppm by weight, comprising:reacting a chlorosilane with an alcohol in a water-free and solvent-free phase to form a product mixture containing alkoxysilane and residual acidic chloride, with removal of resultant hydrogen chloride from the product mixture,then adding liquid or gaseous ammonia, in an amount corresponding to a stoichiometric excess, based on the content of acidic chloride, to form an ammonia-containing product mixture,treating the ammonia-containing product mixture at a temperature between 10 and 50.degree. C., wherein the ammonia and acidic chloride undergo neutralization, to form a crude product, and optionally, then separating off a salt formed in the course of neutralization, from the crude product, andrecovering the alkoxysilane by distilling the crude product.

Abstract: The invention concerns biologically degradable polyesterS which are degraded under the action of micro-organisms in the natural environment. Said polyesters are high molecular weight satistical copolyesters which are made using an aliphatic polyalcohol, an aromatic polycarboxylic acid and also an aliphatic polycarboxylic acid as monomer components. They contain constitutional repeating or recurrent units comprising (i) a polyalcohol and an aromatic polycarboxylic acid and (ii) a polyalcohol and an aliphatic polycarboxylic acid, where over 90% of the units of type (i) are directly bonded with none or at most one other unit of type (i). The polyesters are produced by using a di-isocyanate as an additional monomer component, less isocyanate being used than any of the other monomer components. The present invention also concerns materials made from said biodegradable polyester and a process for producing said polyesters.

Abstract: Mixtures of catenate and cyclic siloxane oligomers of formula I and II ##STR1## wherein the substituents R consist of 3-methacryloxypropyl or 3-acryloxypropyl groups and methoxy, ethoxy and/or propoxy groups alone or together with C.sub.1 -C.sub.18 alkyl, fluoroalkyl, isoalkyl or cycloalkyl groups and/or C.sub.6 -C.sub.12 aryl groups and where not more than one 3-methacryloxypropyl or 3-acryloxypropyl group is attached to one silicon atom and the degree of oligomerization of compounds of the formula I is within the range 2<m<25 and of compounds of the formula II is within the range 2<n<8 and the quotient of the molar proportion of Si/alkoxy groups is .gtoreq.0.5.

Abstract: Cyclopropylamine is prepared from butyrolactone by a process comprising:(a) reacting butyrolactone with hydrogen chloride, thereby yielding chlorobutyric acid, (b) esterifying said chlorobutyric acid with a primary or secondary alcohol having 4-8 carbon atoms, (c) cyclizing the ester with an alkali metal alcoholate of a primary alcohol having 1-3 carbon atoms to give a mixture of cyclopropanecarboxylic acid esters, (d) converting the cyclopropanecarboxylic acid ester mixture into cyclopropanecarboxylic acid amide by reacting the ester mixture with ammonia, and (e) reacting said cyclopropanecarboxylic acid amide with hypohalite ion in a basic medium, thereby forming cyclopropylamine.

Abstract: Aminoacetic acid esters of formula I in which R.sup.1, R.sup.2 and R.sup.3 are identical or different hydrocarbon radicals, or any two of these radicals form a carbon ring with the carbon atom to which they are attached and R.sup.4 is hydrogen or an alkyl radical having 1-4 carbon atoms, are prepared by reacting an .alpha.-substituted malonic acid monoamide ester of formula II ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 have the meanings above, by the Hofmann degradation reaction, with a hypohalite in an amount of up to 1.5 equivalents in an aqueous-basic medium containing base in an amount of 0.8-1.5 equivalents per mol. of starting malonic acid monoamide ester II.

Abstract: A method for preparing nonreactive aminosilicone oils by base-catalyzed equilibration, which entails reacting at least an organosilicon compound with at least one cyclic organosilicon compound in the presence of a basic catalyst in a first step; and in a second step reacting the reaction mixture produced in the first step, in the presence of water, with at least one organosilicon compound.

Abstract: Acetoxysilanes are prepared by a process comprising:(i) reacting at least one chlorosilane with acetic acid in a medium containing acetyl chloride and a catalyst, and removing the hydrogen chloride which is formed during the reaction;(ii) reacting the reaction mixture from step (i) with acetic anhydride; and(iii) separating and obtaining the product acetoxysilane.

Abstract: Oligomeric organosilicon compounds are disclosed of the formula I ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 independently of one another denote H, (C.sub.1 -C.sub.4)alkyl, (C.sub.1 -C.sub.4) alkoxy, (C.sub.1 -C.sub.4) haloalkoxy, (C.sub.1 -C.sub.4)haloalkyl, phenyl, aryl or aralkyl andZ denotes an alkylidene radical having 0-6 carbon atoms, x can be a statistical average of 1-6 andn=1-150 and . . . means that z can be bonded either to the one or the other C atom, and the particular free valency is occupied by a hydrogen.and their use in rubber mixtures and for the production of shaped articles, in particular pneumatic tires.

Abstract: A catalyst for the dehydrogenation of C.sub.6 -C.sub.15 paraffins is disclosed. The catalyst contains, on support, at least one platinum group component, at least one promoter component from the group tin, germanium and lead, and at least one additional modifier. The additional modifier contains at least one alkaline earth metal. The stability of the catalyst is essentially higher than that achieved by conventional use of an alkali metal.