Abstract: A lamp unit includes a lamp provided with a mirror and a house for holding the lamp provided with a mirror. The lamp provided with a mirror includes a discharge lamp including a luminous bulb in which a luminous material is enclosed and a pair of electrodes are opposed to each other in the luminous bulb; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively; and a reflecting mirror for reflecting light emitted from the discharge lamp and having a front opening for emitting the reflected light. The lamp provided with a mirror is formed so as to have a non-airtight structure. The house includes a transmission window made of a material for transmitting light emitted from the front opening and positioned forward in the emission direction of the front opening of the reflecting mirror.

Abstract: A method for cleaning a translucent tube for a discharge lamp having a luminous bulb portion includes the steps of introducing a cleaning fluid from one end of the translucent tube; and allowing the cleaning fluid to flow while bringing the cleaning fluid in contact with at least an inner face of the luminous bulb portion of an inner face of the translucent tube, thereby removing impurities attached on the inner face of the luminous bulb portion.

Abstract: A method for producing a discharge lamp of the present invention includes the steps of: preparing a glass pipe for a discharge lamp having a luminous bulb portion and a side tube portion, and a single electrode assembly including an electrode structure portion that will be formed into a pair of electrodes of the discharge lamp; inserting the single electrode assembly into the glass pipe for a discharge lamp such that the electrode structure portion of the single electrode assembly is positioned in the luminous bulb portion of the glass pipe for a discharge lamp; forming a luminous bulb in which the electrode structure portion is arranged inside by attaching the side tube portion of the glass pipe for a discharge lamp to a part of the single electrode assembly; and forming a pair of electrodes in the luminous bulb by melting and cutting a part of the electrode structure portion selectively.

Abstract: A short arc mercury lamp includes a luminous bulb enclosing at least mercury as a luminous material and a pair of electrodes opposed to each other; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively. The electrode central axis of one of the pair of electrodes is dislocated from the electrode central axis of the other electrode. The shortest distance d (cm) between the head of one of the electrodes and the head of the other electrode is larger than the value of (6M/13.6&pgr;)⅓ when the total mass of the enclosed mercury is M (g).

Abstract: This invention concerns a catalyst for purifying the exhaust gas from a lean-burn engine, which includes a refractory inorganic oxide carrying platinum thereon, a cerium-containing oxide carrying palladium thereon, and an alkali metal compound and/or an alkaline earth metal compound, and a method for the production of the catalyst.

Abstract: A discharge lamp includes a luminous bulb in which a luminous material is enclosed and a pair of electrodes are opposed to each other in the luminous bulb; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively. The pair of metal foils have a pair of external leads on the side opposite to the side electrically connected to the pair of electrodes, respectively. At least one of the pair of external leads is joined to a lead wire for external connection that is to be electrically connected to an external circuit by the plastic flow of a caulking member.

Abstract: A discharge lamp includes a luminous bulb in which a luminous material is enclosed and a pair of electrodes are opposed to each other in the luminous bulb; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively. Each of the pair of metal foils has an external lead on a side opposite to a side electrically connected to a corresponding electrode of the pair of electrodes. At least one of the pair of sealing portions is provided with a reflective film on a surface of the sealing portion in a portion where a connection portion of the external lead and the metal foil is sealed. The reflective film contains a material having a reflectance larger than that of a material constituting the sealing portion.

Abstract: A lamp made of a tube having a light emission portion glass and a side tube portion glass that extends in the light emission portion glass. The lamp has a sealed electrode assembly having an electrical current supply line with one end portion connected to a metal foil. A first portion of the side tube portion where an electrical current supply line is located is heated and this portion is compressed by a first pressure. A second portion of the side tube portion where a metal foil is located is heated and this portion is compressed by a second pressure. The second pressure is made larger than the first pressure.

Abstract: A high-pressure discharge lamp includes a glass housing made of a high-melting vitreous material, a pair of sealing components made of the same high-melting vitreous material and extended from the glass housing. A rare gas and a material that is solid or liquid at room temperature is sealed inside the glass housing. Electrically conductive bars are embedded in the sealing components. The air-tight seals around the electrically conductive bars are formed such that at least one metal material selected from metals and oxides of said metals is provided near the regions lying between the high-melting vitreous material and the electrically conductive bar.

Abstract: Exhaust emission control catalysts capable of efficiently removing nitrogen oxide in exhaust containing a large amount of oxygen emitted from a diesel engine and the like and reducing the generation of particulate matter in the exhaust under high temperature conditions, and a method for controlling the emission of exhaust using the exhaust emission control catalysts. The exhaust emission control catalysts contain copper, praseodymium, and yttrium. The method for controlling the emission of exhaust purifies exhaust containing hydrocarbon and nitrogen oxide in a mole ratio (hydrocarbon/nitrogen oxide) within a range of 0.5 to 30 by bringing the exhaust into contact with the exhaust emission control catalysts. It is possible to efficiently remove nitrogen oxide in the exhaust by reduction while suppressing the oxidation of sulfur dioxide in the exhaust.

Abstract: An exhaust-gas-purifying catalyst is made by depositing on a support iridium serving as a catalyst active substance, sulfur for improving the catalyst activity of iridium and, if necessary, platinum. The sulfur is preferably contained as a sulfate. The exhaust-gas-purifying process of the present invention is a process in which exhaust gas from an internal combustion engine is allowed to pass through the exhaust-gas-purifying catalyst with the exhaust-gas temperature being set in the range of 200° C. to 700° C. at the inlet of the exhaust-gas-purifying catalyst. The above-mentioned composition and process provide an activity for purifying exhaust gas, especially for eliminating nitrogen oxides in an oxidizing atmosphere, in a wide temperature range, allow high heat-resistance and durability, and consequently, are superior in practical use.

Abstract: The present invention provides a mercury-free metal halide lamp with an increased lamp operating voltage and prolonged lamp life without enclosing mercury or excessively increasing an inner pressure of an arc tube. A lamp in accordance with the present invention contains, as a content of a fill material 202, 0.04 mg of ScI3, 0.21 mg of NaI, 7 atm of Xe at room temperature, and 0.1 mg of YI3, which is an iodide of Y, Y having an ionization potential as a simple substance being 5 to 10 eV and a vapor pressure at a temperature of lamp operation being 10−5 or higher.

Abstract: In a high intensity discharge lamp, at least one of an arc bend amount and an apparent width of arc is controlled by a simple configuration at low cost. A high intensity discharge lamp system 110 has a high intensity discharge lamp 111 and an operating circuit 113 for driving the high intensity discharge lamp 111. In the high intensity discharge lamp 111, a rare gas and a filling material 136 containing a metal halide as a light generating substance are enclosed in the arc tube 121 provided with a pair of electrodes 122a and 122b. The lamp system is disposed such that the line connecting the electrodes 122a and 122b is horizontal, and by applying a magnetic field having a vertical magnetic flux thereto and by varying the frequency of alternating current for driving the high intensity discharge lamp 111, at least one of an arc bend amount and an apparent width of arc can be easily controlled.

Abstract: A high-pressure discharge lamp includes a glass housing made of a high-melting vitreous material, a pair of sealing components made of the same high-melting vitreous material and extended from the glass housing. A rare gas and a material that is solid or liquid at room temperature is sealed inside the glass housing. Electrically conductive bars are embedded in the sealing components. The air-tight seals around the electrically conductive bars are formed such that at least one metal material selected from metals and oxides of said metals is provided near the regions lying between the high-melting vitreous material and the electrically conductive bar.

Abstract: A method and apparatus for operating a high pressure discharge lamp is disclosed. Oscillation in the discharge arc periphery, a problem that occurs with high frequency operation, is eliminated. A high pressure discharge lamp is operated by applying thereto a dc or rectangular wave current to which is superposed an ac component shaped by a high frequency ripple signal that has been amplitude modulated by a modulation signal for inducing instantaneous fluctuations in the power supply input to both ends of the arc gap. The ripple level is thereby temporally varied, and stable operating is possible even exceeding the ripple level at which oscillation in the arc periphery begins.

Abstract: A metal halide lamp includes an arc tube containing at least mercury and metal halide. A pair of opposed main electrodes extend in the arc tube. A lamp voltage is applied between the main electrodes. The main electrodes have respective distal ends which are spaced from each other by a predetermined distance “d”.

Abstract: An exhaust-gas-purifying catalyst is made by depositing on a support iridium serving as a catalyst active substance, sulfur for improving the catalyst activity of iridium and, if necessary, platinum. The sulfur is preferably contained as a sulfate. The exhaust-gas-purifying process of the present invention is a process in which exhaust gas from an internal combustion engine is allowed to pass through the exhaust-gas-purifying catalyst with the exhaust-gas temperature being set in the range of 200° C. to 700° C. at the inlet of the exhaust-gas-purifying catalyst. The above-mentioned composition and process provide an activity for purifying exhaust gas, especially for eliminating nitrogen oxides in an oxidizing atmosphere, in a wide temperature range, allow high heat-resistance and durability, and consequently, are superior in practical use.

Abstract: A catalyst which is capable of decomposing and allaying particularly NOx among other harmful components in the diesel engine exhaust gas and, at the same time, depriving by combustion the exhaust gas of carbonaceous particulates, unburned hydrocarbons, and carbon monoxide and a method for purifying the diesel engine exhaust gas by the use of this catalyst are provided. The catalyst for the decomposition of the nitrogen oxides has a refractory three-dimensional structure coated with a copper-containing zirconia powder having deposited copper and the catalytically active oxide of at least one metal selected from the group consisting of tungsten, gallium, nickel, manganese, iron, and cobalt on a zirconia powder. The method for purifying the diesel engine exhaust gas uses the catalyst.

Abstract: A method for manufacturing a high-pressure discharge lamp of the double-ended type having excellent resistance to high-pressure and wherein the internal diameter of a portion of the high-pressure discharge lamp where a light-emitting section and a side tube are adjacent can be reduced without restricting the maximum diameter of an electrode on a side where it projects into the light-emitting section. An electrode assembly 105 is arranged within an evacuated glass bulb 2 such that an end of electrode 102 where a coil 102b is wound is positioned within the light-emitting section 3. In this condition, the portion where the light-emitting section 3 and the side tube 4a (4b) are adjacent is heated by a burner 300. The internal diameter of the side tube 4a (4b) can thereby be formed with a reduced-diameter section 7, whose diameter is smaller than that of the electrode rod 102a without restricting the diameter at the location of the coil 102b.

Abstract: A method and apparatus for operating a high pressure discharge lamp is disclosed. Oscillation in the discharge arc periphery, a problem that occurs with high frequency operation, is eliminated. A high pressure discharge lamp is operated by applying thereto a dc or rectangular wave current to which is superposed an ac component shaped by a high frequency ripple signal that has been amplitude modulated by a modulation signal for inducing instantaneous fluctuations in the power supply input to both ends of the arc gap. The ripple level is thereby temporally varied, and stable operating is possible even when exceeding the ripple level at which oscillation in the arc periphery begins.