Abstract: Cerium oxide powder having carbonate groups and made of crystalline primary particles containing cerium oxide and having carbonate groups on the surface and in a region close to the surface, and having a BET surface area of from 25 to 150 m2/g, a mean diameter of from 5 to 50 nm, a carbonate concentration in the region close to the surface decreasing inwardly from the surface, a carbon content due to carbonate groups on the surface of from 5 to 50% by area, a carbon content due to carbonate groups at a depth of about 5 nm in a region close to the surface of from 0 to 30% by area, a content of cerium oxide calculated as CeO2 and based on the powder of at least 99.5% by weight and a content of organic and inorganic carbon of from 0.01 to 0.3% by weight. A dispersion containing this powder.

Abstract: Nanoscalar, pyrogenically produced yttrium-zirconium mixed oxide which has a BET surface area of between 1 and 600 m2/g, a total chloride content of less than 0.05 wt. % and does not exhibit a conversion into the monoclinic phase during storage is produced by atomizing yttrium compounds and zirconium compounds and reacting them in a flame. The mixed oxide can be used as ceramic raw material.

Abstract: The present invention provides a dispersion, which contains nano-sized zinc oxide particles, a coating preparation containing the dispersion, a process for the production of the dispersion, and a coating preparation containing the dispersion, and a use of the coating preparation.

Abstract: Surface-modified indium-tin oxides are produced by mixing the oxides with the surface-modifying agent in liquid or vapour form and heat treating the mixture. They can be used to produce coating systems.

Abstract: Mixed oxide powder containing indium and tin, with a proportion of indium oxide of between 90 and 98 wt. % and a BET surface area of 40 to 120 m2/g, which is in the form of aggregates having an average circumference of less than 500 nm, consists of at least 95% of an indium oxide phase and displays an oxygen content that is lower than the content that theoretically results from In2O3 and SnO2. It is produced by mixing a solution of an indium compound with a solution of a tin compound, atomising this mixture of solutions, pyrolysing the atomised mixture of solutions in a first zone of a reactor and in a second zone of the reactor, following pyrolysis, adding reducing gases to the pyrolysed mixture at one or more points in a quantity such that overall a reducing atmosphere is established in this second zone, and separating the resulting solid from the waste gases in a further, third zone, in which a reducing atmosphere likewise still prevails.

Abstract: A dispersion of pyrogenically produced cerium oxide, which does not contain any particles larger than 1 ?m, is produced by dispersing a pyrogenically produced cerium oxide in water by means of a dissolver, centrifuging it, separating the supernatant from the bottom product, and again dispersing the supernatant by means of ultrasound. The dispersion can be used for chemical-mechanical polishing (CMP).

Abstract: Methods of making hydrophobic, pyrogenically produced silica having a tamped density, of 55 to 200 g/l. Said silica is produced by hydrophobizing pyrogenically produced silica by reaction with a halogen free silane and then compacting it with means consisting of a roller compactor or a belt filter press. The silica may be used for the production of dispersions.

Abstract: Zinc oxide powder is prepared by a process having the following steps a) generating of a zinc vapor-containing stream in a vaporization zone; b) oxidizing the zinc vapor by reaction with an oxygen-containing gas thereby forming zinc oxide powder in an oxidation zone; and c) cooling of the reaction mixture with water or an inert gas, and separation of the zinc oxide powder in a cooling/isolation zone, wherein aa) in the vaporization zone, a gas stream of an inert gas and a fuel gas is passed through a zinc melt which has a temperature of 450 to <900° C., thereby forming zinc vapor, the content of fuel gas being 1 to 50 vol. %, based on the sum of inert gas and fuel gas, and the molar quotient of zinc vapor to fuel gas being 0.01 to 50, and bb) in the oxidation zone, a second gas stream, which contains an oxygen-containing gas and steam, is added to the gas stream of zinc vapor, fuel gas and inert gas in an amount such that the temperature in the oxidation zone is from 500 to 1100° C.

Abstract: Pyrogenically prepared, doped zinc oxide powder, wherein the doping component comprises at least one oxide from the group aluminum, gallium, indium, germanium, tin and is present in the doped zinc oxide powder in an amount of from 0.005 to 15 wt. %, and wherein the doped zinc oxide powder is in the form of aggregates of primary particles having a mean maximum diameter of from 30 to 400 nm. It is prepared by oxidation from zinc powder and at least one doping agent, wherein the process zones vaporisation, nucleation, oxidation and quenching are passed through and the doping agent is metered in in the nucleation zone, in which the temperature is below the boiling temperature of zinc. The doped zinc oxide powder can be used in electrically conductive lacquers and coatings.

Abstract: Cerium oxide powder having carbonate groups and made of crystalline primary particles containing cerium oxide and having carbonate groups on the surface and in a region close to the surface, and having a BET surface area of from 25 to 150 m2/g, a mean diameter of from 5 to 50 nm, a carbonate concentration in the region close to the surface decreasing inwardly from the surface, a carbon content due to carbonate groups on the surface of from 5 to 50% by area, a carbon content due to carbonate groups at a depth of about 5 nm in a region close to the surface of from 0 to 30% by area, a content of cerium oxide calculated as CeO2 and based on the powder of at least 99.5% by weight and a content of organic and inorganic carbon of from 0.01 to 0.3% by weight. A dispersion containing this powder.

Abstract: Mixed oxide powder containing indium and tin, with a proportion of indium oxide of between 90 and 98 wt. % and a BET surface area of 40 to 120 m2/g, which is in the form of aggregates having an average circumference of less than 500 nm, consists of at least 95% of an indium oxide phase and displays an oxygen content that is lower than the content that theoretically results from In2O3 and SnO2. It is produced by mixing a solution of an indium compound with a solution of a tin compound, atomising this mixture of solutions, pyrolysing the atomised mixture of solutions in a first zone of a reactor and in a second zone of the reactor, following pyrolysis, adding reducing gases to the pyrolysed mixture at one or more points in a quantity such that overall a reducing atmosphere is established in this second zone, and separating the resulting solid from the waste gases in a further, third zone, in which a reducing atmosphere likewise still prevails.

Abstract: Pyrogenically prepared, doped zinc oxide powder, wherein the doping component comprises at least one oxide from the group aluminum, gallium, indium, germanium, tin and is present in the doped zinc oxide powder in an amount of from 0.005 to 15 wt. %, and wherein the doped zinc oxide powder is in the form of aggregates of primary particles having a mean maximum diameter of from 30 to 400 nm. It is prepared by oxidation from zinc powder and at least one doping agent, wherein the process zones vaporisation, nucleation, oxidation and quenching are passed through and the doping agent is metered in in the nucleation zone, in which the temperature is below the boiling temperature of zinc. The doped zinc oxide powder can be used in electrically conductive lacquers and coatings.

Abstract: The present invention provides a dispersion, which contains nano-sized zinc oxide particles, a coating preparation containing the dispersion, a process for the production of the dispersion, and a coating preparation containing the dispersion, and a use of the coating preparation.

Abstract: Nanoscale, pyrogenically produced zinc oxide having a BET surface area of 10 to 200 m2/g, which is in the form of aggregates of anisotropic primary particles and whereby the aggregates display an average diameter of 50 to 300 nm. It is obtained from zinc powder, which is converted to zinc oxide powder in the four successive reaction zones, evaporation zone, nucleation zone, oxidation zone and quench zone. It can be used in sunscreen formulations.

Abstract: A method for the quantitative determination of silica oil or siloxane concentrations present in trace quantities in silicas or pyrogenic oxides by the quantitative evaluation of proton spectra is presented. The silica or pyrogenic oxide of interest is dispersed in a suitable organic solvent and the phases are then separated. The liquid phase is evaporated to a dry residue which is then redissolved in a deuterated solvent. The redissolved residue is evaluated quantitatively by proton NMR spectroscopy to determine the concentration of silica oil or siloxane by measuring the integral of the methyl silyl protons present in the 1H spectra and comparing same to the integral of the deuterated solvent.

Abstract: An apparatus and method for dispensing fine particle material from a container such as a flexible intermediate bulk container. The invention includes a dispensing assembly that has a dispensing device that is secured to an outlet tube of the container. Securement is achieved by a strap member wrapped about the container's outlet tube and a clamping casing and/or by an inflatable member that expands outward from the clamping casing. The casing surrounds a transport tube which is axially shiftable following securement of the clamping casing to the outlet tube. A head piece with gas cavity and radial and oblique extending ports is provided at the end of the transport tube. The dispensing device is inserted into the outlet tube below a blocking member provided at the base of the outlet tube. Following attachment of the outlet tube to the clamping casing, the blocking member is released. The transport tube is then released from a first position, shifted and then fixed in a second position.

Abstract: The thickening effect of flame hydrolysis produced silicon dioxide is determined by making a dispersion of the flame hydrolysis produced silicon dioxide in a liquid such as water or ethanol and measuring the turbidity of this dispersion.