Abstract: An internal combustion engine in which an SOx trap catalyst able to trap SOx contained in exhaust gas is arranged in an engine exhaust passage upstream of an NOx storing catalyst. The SOx trap catalyst is strengthened in basicity compared with the NOx storing catalyst to an extent so that when the temperature of the SOx trap catalyst is in the temperature range at the time of ordinary operation, that is, substantially 150° C. to substantially 400° C., the NOx purification rate by the SOx trap catalyst becomes less than substantially 10 percent of the NOx purification rate by the NOx storing catalyst. When NOx should be released from the NOx storing catalyst, the air-fuel ratio of the exhaust gas flowing into the SOx trap catalyst is temporarily switched from lean to rich.

Abstract: In an internal combustion engine, the engine is formed so that an output of an electric motor can be superposed on an output of the engine. In the engine exhaust passage upstream of the NOX storage catalyst, an SOX trap catalyst able to trap the SOX contained in the exhaust gas is arranged. When regenerating the SOX trap catalyst, the vehicle drive power from the engine and the vehicle drive power from the electric motor are adjusted so that the SOX concentration in the exhaust gas flowing out from the SOX trap catalyst becomes less than a predetermined SOX concentration during the regeneration period.

Abstract: A fuel addition valve that adds fuel into the exhaust gas passage of the engine in the form of fine fuel droplets, an upstream NOx adsorption-reduction catalyst, and a downstream NOx adsorption-reduction catalyst are arranged in this order. Platinum Pt and palladium Pd, as noble metal, are supported on the downstream NOx adsorption-reduction NOx catalyst such that the ratio of the mole number of the platinum Pt to the sum of the mole numbers of the platinum Pt and the palladium Pd is approx. 50% to approx. 80%. Only platinum Pt is supported on the upstream NOx adsorption-reduction catalyst. According to this structure, even when liquid fuel is supplied into exhaust gas, NOx can be effectively released from the NOx adsorption-reduction catalyst, and further the amount of NOx that the NOx adsorption-reduction catalyst can adsorb at a low temperature increases.

Abstract: An SOX trap catalyst 12 and NOX purification catalyst 13 are arranged in an engine exhaust passage. A substrate 50 of the NOX purification catalyst 13 is formed with a coat layer comprised of at least the two layers of an upper coat layer 51 and a lower coat layer 52. The lower coat layer 52 is formed from an NOX storage catalyst storing the NOX contained in the exhaust gas when the air-fuel ratio of the exhaust gas is lean and releasing the stored NOX when the air-fuel ratio of the exhaust gas is a stoichiometric air-fuel ratio or rich. The upper coat layer 51 is formed from a material of a weaker basicity than this NOX storage catalyst.

Abstract: An engine exhaust passage has an SOx trapping catalyst (11), a particulate filter (13) holding an NOx storing/reducing catalyst, and an NOx storing/reducing catalyst (15) forming a post-treatment system and a fuel feed valve (17) for feeding fuel for post processing in the post-treatment system arranged inside it. When any catalyst has a degree of degradation exceeding a predetermined degree of degradation, the method of feeding the post-treatment fuel is reset so that the post-treatment fuel required for purification of the exhaust gas can be fed into the catalyst with the lowest degree of degradation to make the catalyst with the lowest degree of degradation handle the purification action of the exhaust gas.

Abstract: When a search character string is input via a key input section and a handwriting input section, if a spelling is input, a character is input directly by a key input operation or a recognized character is input by a handwriting input operation. If pinyin is input to input a Chinese character, not only are alphabetic characters input by a key input operation, but also the four tones area input by touching a four-tone input screen displayed on the handwriting input section. Accordingly, not only can ordinary characters be input as usual, of course, but also Chinese-specific four tones can be input easily by a touch operation at the handwriting input section even when a pinyin character is input.

Abstract: A particulate matter-oxidizing material which enhances the rate of oxidizing the particulate matter at low temperatures (not higher than about 300° C.), and of which the action for purifying NOx by reduction at high temperatures (not lower than about 500° C.) is not impaired by the oxidizing action. The oxidizing material contains a cerium-zirconium composite oxide for purifying, by burning, the particulate matter in the exhaust gas from a lean-burn internal combustion engine, wherein the cerium-zirconium composite oxide contains cerium in an amount of 0.1 to 20 mol % based on the total mol number of metal atoms that are contained. Desirably, the cerium-zirconium composite oxide further contains at least one kind of metal (M) selected from the rare earth metals (excluding cerium), and the molar ratio of M/Ce is 0.1 to 10.

Abstract: It is an object of the invention to provide a technology for appropriately recovering a decreased HC oxidizing ability of rhodium (Rh), in an exhaust gas control apparatus including a catalyst that contains rhodium (Rh) and a particulate filter (5). In this exhaust gas control apparatus, rich-spike control is prohibited and a NOx storage reduction catalyst is placed in a reduction atmosphere during a period in which a temperature of the NOx storage reduction catalyst is equal to or higher than a predetermined temperature, in a course of decreasing the temperature of the NOx storage reduction catalyst after a PM trapping ability forcible recovery process of the particulate filter (5) is completed. Thus, the decreased HC oxidizing ability of rhodium (Rh) is recovered.

Abstract: An engine exhaust passage is provided with a fuel addition valve (14) for adding fuel in the form of atomized drops, an oxidation catalyst (11), and an NOx storage and reduction catalyst (12) in that order. The oxidation catalyst (11) carries as a precious metal not only platinum Pt, but also palladium Pd. A molar ratio of the platinum Pt with respect to the sum of the platinum Pt and palladium Pd carried on the oxidation catalyst (11) is set to between about 50 percent to about 80 percent.

Abstract: The invention provides a technology that enables to prevent sulfur components contained in reducing agent added from flowing into an NOx catalyst thereby keeping a high NOx removing rate. An S-trapping catalyst 11 for trapping sulfur components contained in exhaust gas discharged from an internal combustion engine 1, an S-trapping catalyst 12 for trapping sulfur components contained in reducing agent added to the exhaust gas from which sulfur components have been trapped by the S-trapping catalyst 11 are provided, thereby preventing an NOx catalyst 14 from being poisoned by sulfur.

Abstract: An SOx trap catalyst (11) able to trap SOx contained in exhaust gas is arranged in an engine exhaust passage upstream of an NOx storing catalyst (12). When the SOx trap rate by the SOx trap catalyst (11) falls, the air-fuel ratio of the exhaust gas flowing into the SOx trap catalyst (11) is maintained lean and in that state the SOx trap catalyst (11) is raised in temperature. The SOx trapped at that time diffuses inside the SOx trap catalyst (11), whereby the SOx trap rate is restored.

Abstract: An exhaust purification device, including a NOx storing catalyst comprised of a precious metal catalyst and NOx absorbent, arranged in an engine exhaust passage, which increases the ratio of the nitrogen dioxide to the nitrogen monoxide produced when burning fuel under a lean air-fuel ratio when the NOx storing catalyst is not active compared with the time when the NOx storing catalyst is active under the same engine operating conditions and stores the nitrogen dioxide contained in the exhaust gas in the NOx absorbent at that time.

Abstract: In an exhaust emission control apparatus having an NOx catalyst disposed on an exhaust passage of an internal combustion engine, the present invention is intended to suppress deterioration in exhaust emissions when the temperature of the NOx catalyst is raised. In case where the temperature of the NOx catalyst need be raised, an amount of nitrogen oxides occluded in the NOx catalyst is decreased in advance to the raising of the temperature of the NOx catalyst, whereby the amount of nitrogen oxides to be discharged from the NOx catalyst upon raising the temperature of the NOx catalyst can be decreased.

Abstract: An SOx trap catalyst (11) able to trap SOx contained in exhaust gas is arranged in an engine exhaust passage upstream of an NOx storing catalyst (12). When the SOx trap rate by the SOx trap catalyst (11) falls, the air-fuel ratio of the exhaust gas flowing into the SOx trap catalyst (11) is maintained lean and in that state the SOx trap catalyst (11) is raised in temperature. The SOx trapped at that time diffuses inside the SOx trap catalyst (11), whereby the SOx trap rate is restored.

Abstract: A NOx storing catalyst (11) comprising a precious metal catalyst (46) and NOx absorbent (47) is arranged in an exhaust passage. When the air-fuel ratio of the exhaust gas is lean, the storing catalyst cold stores the NO2 contained in the exhaust in the absorbent when the catalyst is inactive and hot stores the cold stored NO2 in the absorbent when the catalyst is made active. The NO2 contained in the exhaust is cold stored in the absorbent when the catalyst is not activated, and when a predetermined NOx storing catalyst restoring condition (107) is met, a NOx storing catalyst restoring control (109, 115) including raising the NOx storing catalyst temperature to a predetermined temperature to active it (109) is executed so as to restore the cold storing capability of the NOx absorbent.

Abstract: A storage-reduction type NOx purifying catalyst includes a monolith substrate having formed thereon a coat layer containing a cerium-zirconium composite oxide and a cerium-free oxide, a noble metal and an NOx storing material being supported on the coat layer and the cerium content of the cerium-zirconium composite oxide being less than 30 mol % based on the total molar number of metal atoms contained.

Abstract: An exhaust gas purifying apparatus for an internal combustion engine, wherein the efficiency of exhaust gas purification is enhanced by optimally controlling the operating condition of a plasma generator mounted in an exhaust passage in accordance with the exhaust gas atmosphere. The exhaust gas purifying apparatus includes a detection unit for detecting exhaust water content and exhaust temperature; and a control unit for controlling at least one of two factors, frequency or voltage of an AC voltage used to operate the plasma generator mounted in the exhaust passage, in accordance with the detected exhaust water content and exhaust temperature.

Abstract: An exhaust gas cleaning catalyst is formed of a carrier layer, and a noble metal catalyst and a SOx absorbing agent both carried on the carrier layer. The carrier layer of the exhaust gas cleaning catalyst includes at least a first distribution portion and a second distribution portion each having a different sulfate retention level. The sulfate retention level of the first distribution portion is lower than the sulfate retention level of the second distribution portion, and the noble metal catalyst is carried on the first distribution portion such that a SOx that has been oxidized on the noble metal catalyst diffuses toward the second distribution portion so as to be settled therein.

Abstract: A particulate matter-oxidizing material which enhances the rate of oxidizing the particulate matter at low temperatures (not higher than about 300° C.), and of which the action for purifying NOx by reduction at high temperatures (not lower than about 500° C.) is not impaired by the oxidizing action. The oxidizing material contains a cerium-zirconium composite oxide for purifying, by burning, the particulate matter in the exhaust gas from a lean-burn internal combustion engine, wherein the cerium-zirconium composite oxide contains cerium in an amount of 0.1 to 20 mol % based on the total mol number of metal atoms that are contained. Desirably, the cerium-zirconium composite oxide further contains at least one kind of metal (M) selected from the rare earth metals (excluding cerium), and the molar ratio of M/Ce is 0.1 to 10.

Abstract: An exhaust purification device, including a NOx storing catalyst comprised of a precious metal catalyst and NOx absorbent, arranged in an engine exhaust passage, which increases the ratio of the nitrogen dioxide to the nitrogen monoxide produced when burning fuel under a lean air-fuel ratio when the NOx storing catalyst is not active compared with the time when the NOx storing catalyst is active under the same engine operating conditions and stores the nitrogen dioxide contained in the exhaust gas in the NOx absorbent at that time.