摘要:
A method of the heat-retention in a blind riser in metal casting by using a sand mould, characterized in that an exothermic moulded composition is arranged in a drag holding cavity below a blind riser in the cope of the mould or in the neighborhood of the blind riser before the melt is poured, and thereafter the melt is poured to cause the exothermic moulded composition to float up into the blind riser to retain heat therein.
摘要:
An engine control system includes a unit which outputs a command for changing an air-fuel ratio of an exhaust gas, a unit which computes an in-cylinder oxygen concentration, a memory which stores a first value and a second value of parameters (ignition timing, injection pressure, pilot injection quantity). The first value is set in a case that the in-cylinder oxygen concentration is a first oxygen concentration. The second value is set in a case that the in-cylinder oxygen concentration is a second oxygen concentration which is higher than the first oxygen concentration. The values of the parameters are set in such a manner as to correlate to the in-cylinder oxygen concentration of during a transition period of the air-fuel ratio. The values of the parameters are obtained by an interpolation based on the first and the second value of the parameter and the in-cylinder oxygen concentration.
摘要:
A superconducting magnet apparatus obtains high magnetic field uniformity without increasing the volume of a magnetic material even against disturbances. The superconducting magnet apparatus has a circular superconducting coil which generates a magnetic field; a coil vessel which contains the superconducting coil 11 together with refrigerant; a thermal shield arranged so as to surround the coil vessel; a vacuum vessel with inside kept vacuum which surrounds the thermal-shield; and magnetic materials and for correcting the magnetic field, the magnetic materials being arranged in the vacuum vessel; wherein the magnetic materials and are supported by a heat-insulation support medium fixed to the coil vessel.
摘要:
An exhaust gas cleaning apparatus includes a combustion mode shifter that shifts combustion in a cylinder of an engine from a lean-burn mode to a rich-burn mode for enabling a LNT to reduce NOx contained in the exhaust gas. The combustion mode shifter is configured to: estimate a torque-producing fuel quantity for a fuel injection made by a fuel injector when the combustion is in the lean-burn mode; estimate an excess oxygen ratio for an upcoming fuel injection during the shifting of the combustion from the lean-burn mode to the rich-burn mode; estimate a fuel burning percentage for the upcoming fuel injection based on the excess oxygen ratio; set a command injection quantity for the upcoming fuel injection based on the torque-producing fuel quantity and the fuel burning percentage; and control the fuel injector to inject the command injection quantity of fuel into the cylinder in the upcoming fuel injection.
摘要:
A superconducting magnet includes: first and second torus coolant containers substantially symmetrically, vertically arranged to have a space and a symmetrical plane therebetween for storing a coolant. Each of the first and second torus coolant containers includes therein a main coil bobbin with a main coil for generating a measurement magnetic field, a shield coil bobbin with a shield coil for generating a shielding magnetic field for suppressing outside leak of the measurement magnetic field, a plate member vertically reinforced at a plane thereof opposite to a plane thereof facing the symmetrical plane for supporting the shield coil bobbin and the main coil bobbin. The main coil bobbin is further supported by the shield coil bobbin, to cause the main coil to generate the measurement magnetic field having a substantially uniform magnetic field intensity at a middle region of the space. A magnetic resonance imaging apparatus using the superconducting magnet is also disclosed.
摘要:
A superconducting magnet includes: first and second torus coolant containers substantially symmetrically, vertically arranged to have a space and a symmetrical plane therebetween for storing a coolant. Each of the first and second torus coolant containers includes therein a main coil bobbin with a main coil for generating a measurement magnetic field, a shield coil bobbin with a shield coil for generating a shielding magnetic field for suppressing outside leak of the measurement magnetic field, a plate member vertically reinforced at a plane thereof opposite to a plane thereof facing the symmetrical plane for supporting the shield coil bobbin and the main coil bobbin. The main coil bobbin is further supported by the shield coil bobbin, to cause the main coil to generate the measurement magnetic field having a substantially uniform magnetic field intensity at a middle region of the space. A magnetic resonance imaging apparatus using the superconducting magnet is also disclosed.
摘要:
An MRI apparatus is characterized in that magnet members for compensating the magnetic field are disposed to a thermal shield system of the superconducting apparatus. It is another feature of the present invention that the magnet members for compensating the magnetic field are disposed at positions where temperature change in the vacuum chamber is not transferred to the interior of the vacuum chamber.
摘要:
An exhaust gas cleaning apparatus includes a LNT, a fuel adding device, an exhaust gas returning passage, and a controller. The LNT is provided in an exhaust gas passage of an engine. The fuel adding device is located upstream of the LNT to add fuel to exhaust gas flowing through the exhaust pipe. The exhaust gas returning passage branches off from the exhaust gas passage at a position downstream of the fuel adding device. The controller controls the apparatus to selectively operate in one of first and second modes according to the operating condition of the engine. In the first mode, the fuel adding device adds the fuel to the exhaust gas with the exhaust gas returning passage closed; in the second mode, the exhaust gas is partially returned to an intake air passage through the exhaust gas returning passage without the fuel being added by the fuel adding device.
摘要:
An exhaust gas purification device senses an air-fuel ratio of exhaust gas flowing into a catalyst and performs rich purge control for supplying fuel for reduction to the catalyst. The device calculates a total reducing agent amount consumed for the reduction during the rich purge control based on the air-fuel ratio and a fresh air amount as of the rich purge control. The device sets a specified air-fuel ratio state for controlling the air-fuel ratio in a certain range enabling more precise measurement of the air-fuel ratio than in the rich purge control. The device corrects the total reducing agent amount based on a difference between an injection amount command value as of the rich purge control and the injection amount command value in the specified air-fuel ratio state and the air-fuel ratio sensed in the specified air-fuel ratio state.
摘要:
An NOx catalytic converter, which includes an NOx storage and reduction catalyst, absorbs NOx contained in exhaust gas of an engine. The absorbed NOx is deoxidized and eliminated when an NOx deoxidizing agent is supplied to the catalytic converter. An ECU determines a purifying performance of the catalytic converter based on one of an amount of supplied NOx deoxidizing agent, which is required to deoxidize and remove absorbed NOx at the NOx catalytic converter, and a parameter that correlates with the amount of the supplied NOx deoxidizing agent. The ECU prohibits the determining of the purifying performance of the catalytic converter when it is determined that supplied unburnt fuel, which is supplied to the catalytic converter, is in an excessive state.