Abstract: In a component having vibration-damping properties, a mixture for manufacturing the component, and a method of manufacturing such a component, the component has granular and/or grain- and/or flake-shaped piezoelectric particles which are embedded in a polymer matrix in a proportion of at least 10 volume %. In order to improve the damping effect, at least some of the piezoelectric particles have a polarization which is different from zero.

Abstract: In a component having vibration-damping properties, a mixture for manufacturing the component, and a method of manufacturing such a component, the component has granular and/or grain- and/or flake-shaped piezoelectric particles which are embedded in a polymer matrix in a proportion of at least 10 volume %. In order to improve the damping effect, at least some of the piezoelectric particles have a polarization which is different from zero.

Abstract: The invention relates to a method and a device for cleaning flowing gases. To reduce the total emissions, nitrogen oxides, especially NO and NOx, are extracted at least partially from the gas to be scrubbed, in the temperature range from 50 and 300° C., preferably between 50 and 150° C. To extract the nitrogen oxides, an intermediate storage medium is used that is composed of a storage material and a supporting material for the storage material. The intermediate storage medium having in particular a composition of the formal chemical formula Ag.CuAl2O4 in an Al2O3 matrix, with the composition being a spinel or being of the spinel type, and with the composition having characteristic spinel lines in the x-ray spectrum, where 0≦x<1.

Abstract: In a component having vibration-damping properties, a mixture for manufacturing the component, and a method of manufacturing such a component, the component has granular and/or grain- and/or flake-shaped piezoelectric particles which are embedded in a polymer matrix in a proportion of at least 10 volume %. In order to improve the damping effect, at least some of the piezoelectric particles have a polarization which is different from zero.

Abstract: An exhaust gas purification device includes a porous body of catalytic material of the general formula AaBbO4 disposed in an exhaust gas stream of an engine. The porous body of catalytic material has a characteristic response temperature above which it is catalytically active to reduce pollutants in the presence of a reducing agent. The porous body stores at least 20% by volume hydrocarbons at temperatures below the response temperature. A represent at least one element selected from Mg, Ca, Mn, Fe, Ni, Co, Cu, Zn, Sn, Ti and A+B is less than 3, A is greater than 0 and B greater than 0.

Abstract: The present invention is directed to a purification device that includes a porous body and a catalyst. To reduce the emission of pollutants, a pollutant-containing stream of gas flows through the porous body.

Abstract: A process for the catalytic reduction of NO.sub.x, the reduction taking place in the presence of a catalyst which comprises(a) from 20 to 97 wt % of A.sub.2 O.sub.3,(b) from 1 to 40 wt % of CuO,(c) from 1 to 50 wt % of ZnO,(d) from 1 to 40 wt % of Ag,(e) from 0 to 2 wt % of Pt,(f) from 0 to 20 wt % of oxides of rare earth metals, elements of the 3rd subgroup of the Periodic Table of the Elements or mixtures thereof,based on the total weight of the components (a) to (e), which adds up to 100 wt %, wherein, in each case, up to half the weight of the component (a) may be replaced by Fe.sub.2 O.sub.3, Cr.sub.2 O.sub.3, Ga.sub.2 O.sub.3 or mixtures thereof, of the component (b) by CoO, of the component (c) by MgO, of the component (d) by Au and of the component (e) by Pd, Ru, Os, Ir, Rh, Re or mixtures thereof, is used for reducing NO.sub.x, especially in combustion off-gases, the components (a), (b) and (c) forming a spinel which is doped with the components (d), (e) and (f).

Abstract: The present invention relates to a method for operating a catalyst for gases, especially for exhaust gases of stoichiometrically operated gasoline engines, wherein a catalyst is exposed to a gas stream and pollutants are catalytically converted. To improve the elimination of pollutants in the starting phase, hydrocarbons present in the gas are temporarily stored by the catalyst at temperatures below a response temperature of the catalyst, particularly below 200.degree. C., and preferably below 150.degree. C. The hydrocarbons are then released at temperatures above the response temperature and the pollutants, such as nitrogen oxides, are catalytically converted with reducing agents, such as hydrocarbons, carbon monoxide and mixtures thereof. The catalyst is a spinel, such as (MgCu)Al.sub.2 O.sub.4, which may also include a catalytically active species, such as WO.sub.3, V.sub.2 O.sub.5 and TiO.sub.2.

Abstract: The present invention relates to a method for operating a purification device, to a purification device and to the use of same. To reduce the emission of pollutants, a filter body through which a fluid can flow and comprising a catalyst, is exposed to a stream of gas which is to be purified. Before the gas enters the catalyst, a reducing agent is added in the flow direction of the gas, and after a certain treatment point, during which the gas, which is to be purified, is flowing in the catalyst, reducing agent is added once more to the flowing gas by a feeding mechanism and contact with the catalyst is maintained.

Abstract: The invention relates to a method and a device for cleaning flowing gases. To reduce the total emissions, nitrogen oxides, especially NO and NOx, are extracted at least partially from the gas to be scrubbed, in the temperature range from 50 and 300.degree. C., preferably between 50 and 150.degree. C. To extract the nitrogen oxides, an intermediate storage medium is used that is composed of a storage material and a supporting material for the storage material. The intermediate storage medium having in particular a composition of the formal chemical formula Ag.CuAl.sub.2 O.sub.4 in an Al.sub.2 O.sub.3 matrix, with the composition being a spinel or being of the spinel type, and with the composition having characteristic spinel lines in the x-ray spectrum, where 0.ltoreq.x<1.