Abstract: Nitrogen oxides are removed from an exhaust gas containing nitrogen oxides and oxygen in an amount larger than its stoichiometric amount relative to unburned components in the exhaust gas, by (i) disposing an exhaust gas cleaner in a flow path of the exhaust gas, the exhaust gas cleaner comprising 0.2-15 weight % (on a metal basis) of fine silver or silver oxides having an average diameter of 10-1,000 nm and supported on a porous inorganic oxide; (ii) introducing hydrocarbons and/or oxygen-containing organic compounds into the exhaust gas on the upstream side of the exhaust gas cleaner; and (iii) bringing the exhaust gas into contact with the exhaust gas cleaner at a temperature of 200.degree.-600.degree. C., thereby causing a reaction of nitrogen oxides with the hydrocarbons and/or oxygen-containing organic compounds.

Abstract: Nitrogen oxides are removed from an exhaust gas containing nitrogen oxides and oxygen in an amount larger than its stoichiometric amount relative to unburned components in the exhaust gas, by (i) disposing an exhaust gas cleaner in a flow path of the exhaust gas, the exhaust gas cleaner comprising 0.2-15 weight % (on a metal basis) of fine silver or silver oxides having an average diameter of 10-1,000 nm and supported on a porous inorganic oxide; (ii) introducing hydrocarbons and/or oxygen-containing organic compounds into the exhaust gas on the upstream side of the exhaust gas cleaner; and (iii) bringing the exhaust gas into contact with the exhaust gas cleaner at a temperature of 200.degree.-600.degree. C., thereby causing a reaction of nitrogen oxides with the hydrocarbons and/or oxygen-containing organic compounds.

Abstract: Nitrogen oxides are removed from an exhaust gas containing nitrogen oxides and oxygen in an amount larger than its stoichiometric amount relative to unburned components in the exhaust gas, by (i) disposing an exhaust gas cleaner in a flow path of the exhaust gas, the exhaust gas cleaner comprising 0.2-15 weight % (on a metal basis) of fine silver or silver oxides having an average diameter of 10-1,000 nm and supported on a porous inorganic oxide; (ii) introducing hydrocarbons and/or oxygen-containing organic compounds into the exhaust gas on the upstream side of the exhaust gas cleaner; and (iii) bringing the exhaust gas into contact with the exhaust gas cleaner at a temperature of 200.degree.-600.degree. C., thereby causing a reaction of nitrogen oxides with the hydrocarbons and/or oxygen-containing organic compounds.

Abstract: A plastic tube extruded from an extruder is conveyed through a plasma treatment apparatus. The plasma treatment apparatus is equipped with a tubular electrode body having a high-voltage side electrode and a grounded-side electrode disposed on a tubular insulator and a high frequency electric power source connected to the electrodes. When the plastic tube is conveyed through the electrode body with one end of the tube open to the atmosphere, a mixture of a glow discharge-stabilizing gas and a treating gas is fed into the other end of the tube and an alternating-current high-voltage is applied to generate a plasma region at a pressure near to atmospheric pressure in which the tube is treated with a glow discharge plasma. This method allows an interior and/or exterior surface of a plastic tube designed to convey a medical fluid to be continuously treated by a glow discharge plasma at atmospheric pressure to form an anti-thrombotic and blood-compatible film on the surface treated.