Abstract: A process for checking the operability of an exhaust gas purification catalyst for diesel engines, which has a light-off temperature and a degree of conversion rCO for carbon monoxide (CO), by direct measurement of the carbon monoxide concentration in combination with a temperature measurement. To evaluate the remaining catalytic activity of the catalyst the difference &Dgr;T between the current catalyst exit temperature TE of the exhaust gas and the light-off temperature TCO,50%,fresh of the fresh catalyst for carbon monoxide stored as a function of the speed and load &Dgr;T=TE−TCO,50%,fresh is determined and the degree of conversion rCO for carbon monoxide is ascertained.

Abstract: A method for catalytic conversion of carbon monoxide with water to carbon dioxide and water in a hydrogen-containing gas mixture (carbon monoxide conversion) by passing the gas mixture over a shift catalyst that is at an operating temperature for the carbon monoxide conversion. The method is carried out with a shift catalyst based on noble metals that is applied to an inert support element in the form of a coating.

Abstract: A PEM fuel cell stack including one or more fuel cells (1) arranged on top of one another, each of which contains a membrane electrode assembly (2) between two electrically conductive bipolar plates (3,4), the surfaces of which are equipped with flow channels (10) open on one side for the supply of reactive gases, whereby the membrane electrode assemblies each comprise a polymer electrolyte membrane (5), both sides of which are in contact with a reaction layer (6,7), whereby the surface area of the reaction layers is smaller than that of the polymer electrolyte membrane and a compressible, coarse-pore gas distribution layer (8,9) made from carbon fiber fabric is inserted between each reaction layer and the adjacent bipolar plates congruent to the reaction lawyers along with seals (11,12) in the area outside the surface covered by the gas distribution layers, whereby the gas distribution layers in the no-load condition display a thickness D1 and the seals a thickness D2.

Abstract: A structured catalyst for selective reduction of nitrogen oxides with ammonia using an ammonia-supplying compound. The catalyst is preferably used for exhaust gas treatment of diesel vehicles powered by diesel motors. The catalyst is characterized by the fact that it contains a reduction catalyst for selective reduction of nitrogen oxides with ammonia and a hydrolysis catalyst for the hydrolysis of urea, where the hydrolysis catalyst is applied in the form of a coating onto the reduction catalyst. By this arrangement of the two catalytic functions in one catalyst the exhaust gas system can be made very compactly and space saving. Moreover, advantageous synergistic effects result from the direct contact of the hydrolysis catalyst and the reduction catalyst.

Abstract: A honeycomb body made from a ceramic material with improved radial pressure resistance that is of cylindrical shape and features a first and a second end face and a cylindrical shell and that is traversed from one end face to the other by axially parallel channels formed by channel walls and distributed across the cross section of the honeycomb body in a regular grid pattern, in which design an outer marginal zone of the honeycomb body, the thickness of which amounts to several channel diameters, encloses a central area. The increase in radial pressure resistance of the honeycomb body is achieved by reinforcing the ceramic material of the cylindrical shell and of the channel walls in the outer marginal zone of the honeycomb body by depositing on or in it one or several inorganic substances for the purpose of increasing its mechanical stability.

Abstract: A process for producing electrical energy with the aid of a fuel cell, which includes the steps of reforming an organic fuel, removing carbon monoxide from the reformate, and reacting the hydrogen present in the reformate with oxygen, in a fuel cell, to thereby produce electrical energy. The carbon monoxide is removed from the reformate by treating the reformate in a bioreactor which contains a thermophilic microorganism strain which metabolizes carbon monoxide, under anaerobic conditions, to give carbon dioxide and hydrogen.

Abstract: The present invention provides processes for checking the operability of a nitrogen oxide storage catalyst during operation of a lean burn engine. The processes of the present invention utilize a nitrogen oxide storage material, a catalytically active component and optionally an oxygen storage material. During lean burn engine operation, damage to the catalytically active components is detected if the nitrogen oxide storage capacity in the kinetically controlled temperature range is lowered and damage to the storage material is detected if the nitrogen oxide storage capacity is lowered in the thermodynamically controlled temperature range.

Abstract: The present invention relates to additive, pigment or colorant materials which may be used for laser marking. The materials comprise oxides of bismuth and at least one additional metal. Preferred laser-markable bismuth-containing oxide compounds are of the formula BixMyOz, where M is at least one metal selected from Zn, Ti, Fe, Cu, Al, Zr, P, Sn, Sr, Si, Y, Nb, La, Ta, Pr, Ca, Mg, Mo, W, Sb, Cr, Ba and Ce, x is from about 0.3 to about 70, y is from about 0.05 to about 8, and z is from about 1 to about 100. The bismuth-containing material may be dispersed in a substrate which is subsequently irradiated by a laser to provide a contrasting mark in the irradiated region.

Abstract: The invention provides a supported metal membrane which contains a metal membrane on a support surface of a porous membrane support. The supported metal membrane is obtainable by applying the metal membrane to the support surface of the membrane support, wherein the pores in the membrane support are sealed, at least in the region of the support surface, prior to applying the metal membrane and are opened by removing the auxiliary substance only after applying the metal membrane.

Abstract: A process for operating an exhaust gas treatment device in a gasoline engine which is operated mainly with a stoichiometric air/fuel ratio and is operated with a rich-mix air/fuel ratio when accelerating or under full load. The exhaust gas treatment device contains a three-way converter catalyst and a first lambda probe upstream of the catalyst and a second lambda probe downstream of the catalyst. The air/fuel ratio is controlled by using the signal from the first lambda probe, whereas the signal from the second lambda probe is used to check the first lambda probe (trim control) and to diagnose the function of the catalyst. Trim control with the second lambda probe is enabled only when, in the event of rich exhaust gas, the voltage difference between the probe voltage for the second lambda probe and a set point voltage is not larger than a predetermined value.

Abstract: Rare earth-transition metal oxides are used as pigments. The rare earth-transition metal oxide pigments are preferably of the formula (RexTm)Oy, where Re is at least one rare earth element, Tm is at least one transition metal, x ranges from 0.08 to 12, and y ranges from x+1 to 2x+2. The pigments are useful as colorants, and possess good stability.

Abstract: A method for conversion of carbon monoxide to carbon dioxide and hydrogen with water in a gas mixture containing hydrogen and other oxidizable components. An oxidation-active noble metal shift catalyst is the catalyst. The necessary operating temperature of the catalyst is established and optionally maintained by partial oxidation of the oxidizable components of the gas mixture.

Abstract: A method for partially coating a cylindrical carrier body with a coating suspension, the carrier body having a cylindrical axis, two end faces, an envelope, and an axial length L, and being provided with a series of channels extending from the first end face to the second end face. A desired coating quantity of the coating suspension is applied onto the carrier body by vertically aligning the cylindrical axis and introducing the coating suspension into the channels through the lower end face. The carrier body, measured from the lower end face, is filled with a filling volume of the coating suspension which is metered, such that the carrier body is only filled up to a height that amounts to a predetermined fraction of its length L. Subsequently, excess coating suspension is removed downward so that the desired coating quantity remains on the carrier body.

Abstract: Rare earth manganese oxides are used as pigments. The pigments are preferably of the formula (RexMn)Oy, where Re is at least one element selected from Y, La and Lanthanide elements, x is from 0.01 to 99, and y is the number required to maintain electroneutrality. Preferred rare earth elements include Y, La, Pr and Nd. The pigments are useful as colorants, and may possess improved reflectance characteristics in the infrared region, thereby reducing IR-induced heat buildup.

Abstract: The present invention relates to additive, pigment or colorant materials which may be used for laser marking. The materials comprise oxides of bismuth and at least one additional metal. Preferred laser-markable bismuth-containing oxide compounds are of the formula BixMyOz, where M is at least one metal selected from Zn, Ti, Fe, Cu, Al, Zr, P, Sn, Sr, Si, Y, Nb, La, Ta, Pr, Ca, Mg, Mo, W, Sb, Cr, Ba and Ce, x is from about 0.3 to about 70, y is from about 0.05 to about 8, and z is from about 1 to about 100. The bismuth-containing material may be dispersed in a substrate which is subsequently irradiated by a laser to provide a contrasting mark in the irradiated region.

Abstract: Laser markable coatings include a marking pigment and a fixing material. The marking pigment may comprise titanium dioxide, zinc oxide, zinc sulfide or the like. The fixing material may comprise bismuth trioxide, antimony oxide and the like, and preferably has a melting temperature below 1,300° C. A preferred laser marking composition includes TiO2 and Bi2O3 in a weight ratio of about 1:1. After application to a substrate and laser irradiation, the fixing material stabilizes the resultant mark.

Abstract: Alkaline earth-manganese oxides are used as pigments. The alkaline earth-manganese oxide pigments are preferably of the formula MexMnOy, where Me is at least one metal selected from Ca, Sr, Ba and Mg, x is from 0.01 to 99, and y is greater than or equal to x+1 and less than or equal to x+2. The pigments are useful as colorants, and also possess improved reflectance characteristics, particularly in the IR region, and may reduce IR-induced heat buildup. These colorants can be used to form colored objects, or coat objects when they are either added into or applied onto materials such as paints, inks, plastics, glasses, ceramics and the like. The patent also covers the production of these pigments.