Abstract: An SCR catalyst using a ?-zeolite in which the molar ratio of SiO2/Al2O3 is from 20 to less than 40, the particle diameter determined by SEM is 0.35 ?m or more, the full width at half maximum (FWHM) of the X-ray diffraction peak for (302) is less than 0.30°, and the amount of adsorbed NH3 is 1 mmol/g or more, or has an amount of adsorbed NH3 following hydrothermal aging of 0.4 mmol/g or more, demonstrates high catalytic activity for NOx reduction at low temperatures following hydrothermal aging while also demonstrating a low level of discharge of irritating ammonia in exhaust gas.

Abstract: A first catalyst for reducing nitrogen oxides comprising a crystalline silicate containing an iron in ?-framework structure wherein a SiO2/Fe2O3 mol ratio is 20-300 and at least 80% of the contained iron is an isolated iron ion Fe3+. A second catalyst for reducing nitrogen oxides comprising a crystalline silicate containing an iron in ?-framework structure wherein a SiO2/Fe2O3 mol ratio is 20-300 and log (SiO2/Al2O3) by mol is at least 2. A predominant part of the contained iron is isolated iron ion Fe3+ and at least a part thereof preferably has a tetrahedral coordination. These catalysts have high hydrothermal stability and exhibit enhanced activity for reducing nitrogen oxides by a reaction with a reducing agent such as ammonia, urea or an organic amine in a broad temperature range between lower temperature and higher temperature.

Abstract: A storage control apparatus of the present invention controls the number of multiple commands issued from a host machine without shutting down the host machine. A communication port of the storage control apparatus carries out communications with the hosts in accordance with the iSCSI protocol. Command processing resources are managed for each communication port. A resource allocation control part calculates the number of commands capable of being received on the basis of the remaining amount of command processing resources inside shared port resources, a change in the number of commands received from a host, communication delay time, and the state of execution of a command issued from a host or the like. A MaxCmdSN is calculated by adding the results of command processing by a command execution part and the receivable number calculated by the resource allocation control part to the value of the latest CmdSN received from a host.

Abstract: A method for removing nitrogen oxides from an oxygen-rich exhaust gas containing nitrogen oxides and hydrocarbons comprising bringing the oxygen-rich exhaust gas into contact with a catalyst comprising (1)(i) a zeolite containing an apatite compound and having an SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of at least 15 and (ii) at least one active metal or (2)(ii) a zeolite containing an apatite compound and having an SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of at least 15, (ii) an alkaline earth metal and (iii) at least one active metal.

Abstract: Nitrogen oxides are removed from an oxygen rich exhaust gas containing nitrogen oxides and hydrocarbons by bringing the oxygen rich exhaust gas into contact with a catalyst composed of phosphorus and at least one active metal contained in a zeolite having a molar ratio of SiO.sub.2 /Al.sub.2 O.sub.3 of at least 15.