Abstract: A polished semiconductor wafer of high flatness is produced by the following ordered steps: slicing a semiconductor wafer from a rod composed of semiconductor material, material-removal processing of at least one side of the semiconductor wafer, and polishing of at least one side of the semiconductor wafer, wherein the semiconductor wafer has, after the material-removing processing and before the polishing on at least one side to be polished, along its margin, a ring-shaped local elevation having a maximum height of at least 0.1 ?m, wherein the local elevation reaches its maximum height within a 10 mm wide ring lying at the edge of the semiconductor wafer.

Abstract: A polished semiconductor wafer of high flatness is produced by the following ordered steps: slicing a semiconductor wafer from a rod composed of semiconductor material, material-removal processing of at least one side of the semiconductor wafer, and polishing of at least one side of the semiconductor wafer, wherein the semiconductor wafer has, after the material-removing processing and before the polishing on at least one side to be polished, along its margin, a ring-shaped local elevation having a maximum height of at least 0.1 ?m, wherein the local elevation reaches its maximum height within a 10 mm wide ring lying at the edge of the semiconductor wafer.

Abstract: A food storage container includes a lid with a vent hole, and a removable cover removably secured to the lid to cover the vent hole. The cover has an evacuation hole. The food storage container further includes a one-way air valve disposed between the vent hole and evacuation hole. When the cover is secured to the lid, the one-way air valve inhibits air flow into the container through the vent hole, and when the cover is not secured to the lid, the one-way air valve allows air flow into the container.

Abstract: A device and process for the wet-chemical treatment of silicon using an etching liquid that contains water, nitric acid and hydrofluoric acid. The etching liquid is activated by introducing nitrogen oxide (NOx) into the etching liquid, before being used for the wet-chemical treatment of silicon. The device consists of a first vessel in which silicon is subjected to a wet-chemical treatment with the aid of an etching liquid, a second vessel in which fresh etching liquid is held ready, and a connecting line between the first vessel and the second vessel, through which nitrogen oxides (NOx) formed in the first vessel during the wet-chemical treatment are passed to the second vessel.

Abstract: A food storage container includes a lid with a vent hole, and a removable cover removably secured to the lid to cover the vent hole. The cover has an evacuation hole. The food storage container further includes a one-way air valve disposed between the vent hole and evacuation hole. When the cover is secured to the lid, the one-way air valve inhibits air flow into the container through the vent hole, and when the cover is not secured to the lid, the one-way air valve allows air flow into the container.

Abstract: A process for the wet-chemical surface treatment of a semiconductor wafer has the semiconductor wafer being treated with an acidic liquid, with at most 10 &mgr;m of material being removed from each surface of the semiconductor wafer, and then this wafer is treated with an alkaline liquid, with at least sufficient material being removed for the crystal regions which have been damaged by a previous mechanical treatment to be completely removed.

Abstract: A process for producing a semiconductor wafer is based upon etching the semiconductor wafer with an etching medium flowing in a laminar flow along a direction of flow toward an edge of the semiconductor wafer. There is a protective shield arranged in front of the edge of the semiconductor wafer, so that the etching medium flows onto the protective shield and not onto the edge of the semiconductor wafer. There is also a process that has the semiconductor wafer being inclined with respect to the direction of flow of the etching medium, so that there is an angle of less than 180° between the direction of flow of the etching medium and a first side of the semiconductor wafer. Also, there is an angle of greater than 180° between the direction of flow of the etching medium and a second side of the semiconductor wafer, and the second side of the semiconductor wafer is subsequently polished.

Abstract: A device and process for the wet-chemical treatment of silicon using an etching liquid that contains water, nitric acid and hydrofluoric acid. The etching liquid is activated by introducing nitrogen oxide (NOx) into the etching liquid, before being used for the wet-chemical treatment of silicon. The device consists of a first vessel in which silicon is subjected to a wet-chemical treatment with the aid of an etching liquid, a second vessel in which fresh etching liquid is held ready, and a connecting line between the first vessel and the second vessel, through which nitrogen oxides (NOx) formed in the first vessel during the wet-chemical treatment are passed to the second vessel.

Abstract: A harvesting machine with a front-mounted harvesting attachment that is pivotable about a shaft running transversely to the direction of travel comprising and capable of lifting when an obstacle is detected that includes a sensing device with at least one double-acting hydraulic piston and cylinder unit, having a first cylinder chamber and a second cylinder chamber, arranged on the harvesting attachment, a control valve associated with the sensing device in such a way that when the sensing device is not operated, the first cylinder chamber is in fluid communication with the second cylinder chamber by a control valve and when the sensing device is operated, fluid communication between the first cylinder chamber and the second cylinder chamber is interrupted by the control valve.

Abstract: A process for producing a semiconductor wafer is based upon etching the semiconductor wafer with an etching medium flowing in a laminar flow along a direction of flow toward an edge of the semiconductor wafer. There is a protective shield arranged in front of the edge of the semiconductor wafer, so that the etching medium flows onto the protective shield and not onto the edge of the semiconductor wafer. There is also a process that has the semiconductor wafer being inclined with respect to the direction of flow of the etching medium, so that there is an angle of less than 180° between the direction of flow of the etching medium and a first side of the semiconductor wafer. Also, there is an angle of greater than 180° between the direction of flow of the etching medium and a second side of the semiconductor wafer, and the second side of the semiconductor wafer is subsequently polished.

Abstract: The present invention involves a harvesting machine with a front-mounted harvesting attachment that is pivotable about a shaft running transversely to the direction of travel comprising and capable of lifting when an obstacle is detected that includes a sensing device with at least one double-acting hydraulic piston and cylinder unit, having a first cylinder chamber and a second cylinder chamber, arranged on the harvesting attachment, a control valve associated with the sensing device in such a way that when the sensing device is not operated, the first cylinder chamber is in fluid communication with the second cylinder chamber by a control valve and when the sensing device is operated, fluid communication between the first cylinder chamber and the second cylinder chamber is interrupted by the control valve.

Abstract: A hydraulic control system for connecting elements, which is particularly applicable for an externally engaged clutch on an engine, comprises a pump for producing an oil stream, a distributing valve for determining the flow path of the oil stream, a throttle serving as a metering orifice and inserted in a flow path causing a pressure gradient in the oil stream, a regulating valve connected by supply and return pipes to the flow path of the first throttle upstream and downstream of the throttle, which has a regulating piston acted upon by the higher oil pressure and displaceable against a spring force, a control groove provided on the regulating piston which operates by a ring groove arranged between the piston chamber and the regulating valve with clutch pipe and tank pipes, a second throttle serving as a time orifice and inserted in an output pipe proceeding from the end region of a spring chamber towards the return pipe and adjustable to the closing time of the clutch and a pressure relief output which proc

Abstract: A disposable cover for an infrared thermometer provides IR window isolation of handling and usage generated forces. The cover comprises a thin sidewall linked to the film window with a collar structure. The collar structure includes one or more characteristics that either isolate the film window from externally applied forces, or develops counter forces in a way that precludes film stretching and other transmission distorting effects. In a preferred embodiment, the probe includes retention ears and the cover includes a rim that cooperatively engages the retention ears. This combination of retention ears and an interlocking rim decreases movement of the cover along the probe axis. The cover of the present invention permits sanitary application of an infrared clinical thermometer without hindering reading accuracy or patient comfort.

Abstract: A disposable cover for an infrared thermometer provides IR window isolation of handling and usage generated forces. The cover comprises a thin sidewall linked to the film window with a collar structure. The collar structure includes one or more characteristics that either isolate the film window from externally applied forces, or develops counter forces in a way that precludes film stretching and other transmission distorting effects. The cover of the present invention permits sanitary application of an infrared clinical thermometer without hindering reading accuracy or patient comfort.

Abstract: Mechanical actuating devices for disc brakes known in the art are of complicated construction and are composed of a large number of parts. The actuating device of the present invention reduces the number of parts by providing an actuating nut with an adjusting screw thread on its outer surface and by disposing the actuating nut in a threaded bore of an actuating or brake piston movably guided in a cylindrical bore of the brake caliper. The actuating nut and brake piston from an automatic brake clearance adjusting device in which the brake piston is progressively moved toward the brake disc on the actuating nut when the actuating stroke exceeds a predetermined amount due to wear of the brake pads.

Abstract: The brake actuating device is disposed in a cylindrical bore of a disc brake caliper leg and comprises an actuating spindle and an actuating nut interconnected by a ball bearing thread. The actuating spindle has a central bore receiving an adjusting spindle surrounded by a sleeve, one end of which is connected to an adjusting nut threaded onto the adjusting spindle and transmitting the actuating force thereon. The other end of the sleeve is accessible through a bore from the outside of the caliper leg and can be turned with a tool in order to reset the adjusting nut for replacement of the worn brake pads.

Abstract: An adjustable brake-actuating device of the spindle and nut type eliminating need of an adjusting thread includes an actuating nut driven by an actuating lever through a one-way clutch, which opens during the release stroke of the lever, and a clutch-spring encircling the actuating nut to limit the release movement of the actuating nut to an amount corresponding to the desired brake pad clearance.