Abstract: Compositions useful for treating the exhaust gases of diesel engines contain zirconium oxide, silicon oxide and at least one oxide of at least one element M selected from among titanium, aluminum, tungsten, molybdenum, cerium, iron, tin, zinc, and manganese, in the following mass proportions of these different elements: silicon oxide: 5%-30%; M-element oxide: 1%-20%; the balance being zirconium oxide; such compositions also have an acidity, as measured by the methylbutynol test, of at least 90% and are prepared by placing a zirconium compound, a silicon compound, at least one M-element compound and a basic compound in a liquid medium, thereby generating a precipitate, maturing the precipitate in a liquid medium and separating and calcining the precipitate.

Abstract: Compositions useful for treating the exhaust gases of diesel engines contain zirconium oxide, silicon oxide and at least one oxide of at least one element M selected from among titanium, aluminum, tungsten, molybdenum, cerium, iron, tin, zinc, and manganese, in the following mass proportions of these different elements: silicon oxide: 5%-30%; M-element oxide: 1%-20%; the balance being zirconium oxide; such compositions also have an acidity, as measured by the methylbutynol test, of at least 90% and are prepared by placing a zirconium compound, a silicon compound, at least one M-element compound and a basic compound in a liquid medium, thereby generating a precipitate, maturing the precipitate in a liquid medium and separating and calcining the precipitate.

Abstract: Compositions useful for treating exhaust gases contain zirconium, titanium and tungsten oxides, and optionally the oxide of an element M selected from among silicon, aluminum, iron, molybdenum, manganese, zinc, tin, and rare earths in the following mass proportions of these different elements: titanium oxide: 20%-50%; tungsten oxide: 1%-20%, M-element oxide: 1%-20%; the balance being zirconium oxide; such compositions are prepared by placing in a liquid medium a zirconium compound, a titanium compound, optionally an M-element compound and a basic compound, adding a tungsten compound to the precipitate suspension thus obtained and having a pH value ranging from 1 to 7, maturing the suspension resulting from the preceding step, and optionally separating the precipitate and calcining same.

Abstract: Compositions useful for treating the exhaust gases of diesel engines contain zirconium oxide, silicon oxide and at least one oxide of at least one element M selected from among titanium, aluminum, tungsten, molybdenum, cerium, iron, tin, zinc, and manganese, in the following mass proportions of these different elements: silicon oxide: 5%-30%; M-element oxide: 1%-20%; the balance being zirconium oxide; such compositions also have an acidity, as measured by the methylbutynol test, of at least 90% and are prepared by placing a zirconium compound, a silicon compound, at least one M-element compound and a basic compound in a liquid medium, thereby generating a precipitate, maturing the precipitate in a liquid medium and separating and calcining the precipitate.

Abstract: This invention relates to an improved amorphous zirconium hydroxide and a method for its production. The hydroxide has a surface area of at least 300 m2/g, a total pore volume of at least 0.70 cm3/g and an average pore size of between 5 nm and 15 nm, and is prepared by a process which comprises the steps of: a) preparing an aqueous solution comprising sulphate anions and a zirconium salt such that the ZrO2:SO3 ratio is 1:0.40 to 1:0.52, (b) chilling the solution to below 25° C., (c) adding an alkali in order to precipitate the amorphous zirconium hydroxide, (d) filtering and washing the precipitated zirconium hydroxide with water or an alkali to remove residual sulphate and chloride, (e) hydrothermally treating the zirconium hydroxide at a pressure of less than 3 barg, and (f) drying the zirconium hydroxide. The zirconium hydroxide of the present invention, which can be doped, is particularly useful in catalytic applications.

Abstract: This invention relates to an improved amorphous zirconium hydroxide and a method for its production. The hydroxide has a surface area of at least 300 m2/g, a total pore volume of at least 0.70 cm3/g and an average pore size of between 5 nm and 15 nm, and is prepared by a process which comprises the steps of: a) preparing an aqueous solution comprising sulphate anions and a zirconium salt such that the ZrO2:SO3 ratio is 1:0.40 to 1:0.52, (b) chilling the solution to below 25° C., (c) adding an alkali in order to precipitate the amorphous zirconium hydroxide, (d) filtering and washing the precipitated zirconium hydroxide with water or an alkali to remove residual sulphate and chloride, (e) hydrothermally treating the zirconium hydroxide at a pressure of less than 3 barg, and (f) drying the zirconium hydroxide. The zirconium hydroxide of the present invention, which can be doped, is particularly useful in catalytic applications.

Abstract: At system initialization, the core routers and the edge routers will begin to exchange routing information that is required for the network to become operational. The notification shaping method of the present invention can be used to prevent the core router from flooding the edge routers with notifications while the edge routers are trying to process routing updates. In the present invention, notifications are sent in a steady flow, and not in bursts. The notification shaping method uses a timer to process the notifications stored in the notification queue. In addition, the notification shaping method comprises three basic steps. Step 1 comprises putting an entry on the notification queue. Step 2 comprises timer expiration. Step 3 comprises responding to an inform.

Abstract: A probe for a position determining apparatus includes a sensing space and a movable stylus supported for three-dimensional position determining movement which extends into the space. A device emits sensing radiation into the space and a collector collects the sensing radiation from the space. A deflector is supported on the stylus within the space to deflect emitted sensing radiation and is movable with position determining movement of the stylus. The deflector concentrates the sensing radiation and the collector is sensitive to variations in the intensity distribution of collected deflected radiation which occur due to the three-dimensional movement of the stylus.

Abstract: A surface-measuring apparatus comprising a probe and means for moving the probe towards and away from a surface under examination and for monitoring such movement, the probe comprising a plurality of closely spaced light-collecting elements arranged in a light-collecting plane, lens means positioned to produce a sharply focussed image of said light collecting elements at an image plane movable relative to said surface by movement of the probe, illuminating means so arranged that the lens unit forms an illuminated spot image of it in the image plane in co-incidence with the image In the image plane of one of the light-collecting elements, and means for measuring the incidence of light on the said one of the light-collecting elements and on surrounding ones of those elements. In one embodiment (FIG.

Abstract: A probe for position-determining apparatus and the like having a housing and in the housing a sensing space and an aperture to the sensing space, a stylus extending out of the sensing space through the aperture, and a stylus-support at the aperture. The stylus is constrained in low-friction engagement with the stylus support towards a generally neutral axis while permitting position-determining displacement on the stylus support. The stylus is linked to the constraining low friction engagement through a lever arrangement including a first lever element extending sideways from and around the stylus and a second lever from the first lever to transfer stylus displacement to the constraining low friction engagement. The lever arrangement includes an abutment engageable by the second lever.

Abstract: A probe for position-determining apparatus and the like has a housing (10) and in the housing a sensing space (60) and an aperture (915) to the sensing space, a stylus (40) extending out of the sensing space through the aperture, a low-friction stylus support (50;17) around the aperture, a resilient element (20;120) for constraining the stylus on to the support and generally towards a neutral axis while permitting position-determining displacement on the support against the constraining element, which is outside the sensing space, while in the sensing space is a sensing arrangement (30, 42; 30, 42, 35, 37) separate from the constraining element to sense directly significant movement of the stylus from the neutral axis without contact with the stylus and to indicate such significant movement of the stylus as a position-determining displacement.