摘要:
Inorganic support materials containing sulphonate and mercapto groups, and a process for the modification of these materials with the corresponding difunctional organosilicon compounds and use thereof as catalysts in acid-catalyzed reactions.
摘要:
A method of producing cyanopyridines by means of the catalytic reaction of methylpyridines with ammonia and oxygen at elevated temperature using catalysts consisting of compounds of the elements antimony, vanadium, silicon, titanium and oxygen and compounds of one or more of the alkali metals as well as a method of producing the catalysts and the catalysts themselves.
摘要:
The invention is relates to a method of producing aryl-substituted, amino-acylated phosphonic-acid derivatives with the aid of metal complexes of chiral amphiphilic ligands in that according to the invention .alpha.-N-acyl-protected, .beta.-substituted alkene phosphone derivatives are asymmetrically hydrogenated in the presence of a chiral rhodium catalyst in a solvent or a suspension. The use of the micelle-forming catalyst makes possible the hydrogenation of unsaturated phosphonic-acid derivatives in water with a high reaction rate with the obtainment of very good enantiomeric excesses.
摘要:
An improved method of producing 3,5,5-trimethylcyclohex-2-ene-1,4-dione (KIP) by the oxidation of 3,5,5-trimethylcyclohex-3-ene-1-one (.beta.-IP) in the presence of managansalene-like catalysts and certain catalytic additives. ##STR1## KIP is an important intermediary product in the synthesis of trimethylhydroquinone, an initial substance in the synthesis of vitamin E. Furthermore, KIP is an initial compound for the synthesis of various carotinoids.
摘要:
Precipitated silica with a sodium sulphate content of 4 to 18 wt. %, particularly with the physical-chemical data:______________________________________Sodium sulphate content: 4-14 wt. %BET surface area (DIN 66131): 100-190 m.sup.2 /gDBP absorption (anhydrous) 208-250 g/100 g(DIN 53601, ASTM D 2414): 3.0-6.5 wt. %(DIN ISO 787/II)Oversize with >63 .mu.m .ltoreq. 10.0 wt. %ALPINE air-jet sieve >150 .mu.m .ltoreq. 0.1 wt. % >250 .mu.m .ltoreq. 0.01 wt. %______________________________________It is prepared by introducing hot water into a precipitation vessel, with stirring, adding water glass, then heating the mixture and maintaining the temperature throughout the remainder of the precipitation period. Water glass and sulphuric acid are added simultaneously during this process. The precipitated silica is then separated from the suspension and the filter cake containing sodium sulphate is dried in a spray drier and ground. The precipitated silica may be used in the production of battery separators.
摘要:
Compacts produced from a pyrogenically produced oxide, magnesium stearate, methyl cellulose and urea are mixed together in the presence of water, compacted, dried, comminuted to a powder, and the powder is pressed with an isostatic press to compacts and the compacts tempered. The resulting compacts have an outside diameter of 16 to 100 mm.
摘要:
The invention relates to new anellated (oxa) hydantoins, and herbicidal compositions containing same. The invention also relates to methods for controlling noxious plants using the anellated (oxa) hydantoins of the invention.
摘要:
A catalyst for the dehydrogenation of C6.sub.6 -C.sub.15 paraffins is disclosed. The catalyst contains, on a 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.
摘要:
Enzymes with modified substrate specificity and methods of obtaining same by the steps of a) determining the structure of two or more enzymes in the same group, b) comparing the structure of the substrate binding sites of the enzymes, and c) modifying selected amino acids by genetic mutation so that the substrate preference of one of the enzymes is altered. The methods are particularly useful for the stereospecific interconversion of oxyacids and aminoacids.
摘要:
Algicides are added to water for the algicidal treatment of the water, especially swimming-pool water. The disadvantages of known methods can be avoided or reduced if chlorohexidine or a salt thereof is used as algicide. Chlorohexidine and its salts are distinguished by a broad spectrum of algicidal action at very low concentrations of use.